Vocab v70

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Scientists demonstrate that it may be possible - for advanced extraterrestrial civilizations - to harvest rotational energy from black holes.

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Edible plants in minnesota

- Thistle roots -Dandelion leaves to be eaten raw are best when they are fresh and young. As they age, the leaves get increasingly bitter. - Stinging Nettles (itch weed): gather with gloves or a piece of clothing. To remove the small needle that poke acid into your skin, heat up the leaves with a fire - Roses, violets, daisies and nasturtiums are not only delightful to look at - they are edible. Their petals and blossoms give salads and desserts, smoothies, syrups and teas a unique and special flavor. - Red clover flowers are high in protein, the leaves are good for salad - Herbalists know that burdock root is powerful medicine, but most would be surprised to learn that the burdock is edible as well. Burdock leaves, stalks and roots are edible and can be downright tasty if you know how to prepare them. Make sure to peel the root with a knife. - All pine needles are edible, though you may find that you like the flavor of some pines over others - Dead poppy seed flowers. Crack open the dried bulb and eat the poppy seeds inside - Acorns (if bitter, they are high in tannic acid which can be removed by boiling) and walnuts (browner the walnut = more mature, better)

"Spider web" is typically used to refer to a web that is apparently still in use (i.e. clean), whereas "cobweb" refers to abandoned (i.e. dusty) webs.

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A vaccine is used to train your immune system.

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A virus is a biological example of the butterfly effect.

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A year ago, astronomers announced they'd found the first known galaxy without dark matter. Called NGC 1052-DF2 - or just DF2 for short - this object is 6.5 million light-years away and roughly the same size as our Milky Way galaxy, but with 200 times fewer stars.

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Scientists demonstrate that it is possible for fish to migrate via ingestion of fish eggs (pictured) by birds.

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pyrite suns

However, pyrite dollars or pyrite suns which have an appearance similar to sand dollars are pseudofossils and lack the pentagonal symmetry of the animal. Pyrite: FeS2

why iguanas sneeze

Iguanas sneeze regularly to rid their bodies of excess salt, and after your iguana sneezes, you'll certainly notice small salt deposits on his nose. These nasal salt deposits are a normal part of your iguana's life and are not a cause for concern.

Moravec's paradox

Moravec's paradox is the observation by artificial intelligence and robotics researchers that, contrary to traditional assumptions, reasoning requires very little computation, but sensorimotor skills require enormous computational resources. (The hard problems are easy, the easy problems are hard.)

Eel life history

The eel is a long, thin bony fish of the order Anguilliformes. Because fishermen never caught anything they recognised as young eels, the life cycle of the eel was a mystery for a very long period of scientific history. Although more than 6500 publications mention eels, much of their life history remains an enigma. The European eel (Anguilla anguilla) was historically the one most familiar to Western scientists, beginning with Aristotle, who wrote the earliest known inquiry into the natural history of eels. He speculated that they were born of "earth worms", which he believed were formed of mud, growing from the "guts of wet soil" rather than through sexual reproduction. Many centuries passed before scientists were able to demonstrate that such spontaneous generation does not occur in nature. In 1777, the Italian Carlo Mondini located an eel's ovaries and demonstrated that eels are a kind of fish. In 1876, as a young student in Austria, Sigmund Freud dissected hundreds of eels in search of the male sex organs. He had to concede failure in his first major published research paper, and turned to other issues in frustration. This was the beginning of his goofy attachment to sex. Larval eels — transparent, leaflike two-inch (five-cm) creatures of the open ocean — were not generally recognized as such until 1893; instead, they were thought to be a separate species, Leptocephalus brevirostris (from the Greek leptocephalus meaning "thin- or flat-head"). In 1886, however, the French zoologist Yves Delage discovered the truth when he kept leptocephali alive in a laboratory tank in Roscoff until they matured into eels, and in 1896 Italian zoologist Giovanni Battista Grassi confirmed the finding when he observed the transformation of a Leptocephalus into a round glass eel in the Mediterranean Sea. (He also observed that salt water was necessary to support the maturation process.) Although the connection between larval eels and adult eels is now well understood, the name leptocephalus is still used for larval eel.

metagenome

The human metagenome includes all organisms that live on or in us. Viruses contribute to the metagenome and establish chronic infection that infest chromosomes; this method will formulate new estimate of the number of genes that confer susceptibility to a given virus and specify alleles for some viruses.

Long-wattled umbrellabird

The male is distinguished by a large throat wattle of feathers, while females and juveniles have no or a much smaller wattle.

The Grey Sisters

were three sisters who shared one eye and one tooth among them.

glial cell function

They have four main functions: (1) to surround neurons and hold them in place; (2) to supply nutrients and oxygen to neurons; (3) to insulate one neuron from another; (4) to destroy pathogens and remove dead neurons.

Space archaeology

Utilizing satellite images to track archeology sites/potential sites

widowmaker

a thing with the potential to kill men.

chirality vs parity

A chiral phenomenon is one that is not identical to its mirror image (see the article on mathematical chirality). The spin of a particle may be used to define a handedness, or helicity, for that particle, which, in the case of a massless particle, is the same as chirality. A symmetry transformation between the two is called parity transformation.

Alice: "Would you tell me, please, which way I ought to go from here?" The Cheshire Cat: "That depends a good deal on where you want to get to." Alice: "I don't much care where." The Cheshire Cat: "Then it doesn't much matter which way you go." Alice: "...So long as I get somewhere." The Cheshire Cat: "Oh, you're sure to do that, if only you walk long enough."

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All I need: good music, good science, and a good internet connection.

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Astronomers report detecting a gravitational wave, named GW190521g, that is associated with, for the first time ever, a flash of light from the merger, within the vicinity of a third very large black hole, of two smaller black holes. No light is typically emitted from the merger of black holes.

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Astronomers report evidence that the chemical element carbon, the fourth most abundant chemical element (after hydrogen, helium and oxygen) in the universe, and one of the most essential chemical elements for the formation of life as we know it, was formed mainly in white dwarf stars, particularly those bigger than two solar masses.

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Astronomers report that J2157, discovered in 2018, is now known to have 34 billion solar masses and is consuming the equivalent of nearly 1 solar mass every day, making it the fastest-growing black hole in the Universe.

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distributed computing projects

A collaborative computing process where many computer users pool their computing power to produce a distributed supercomputer to solve problems such as protein folding.

Tachyonic

A tachyonic field, or simply tachyon, is a field with an imaginary mass.[1] Although tachyonic particles (particles that move faster than light) are a purely hypothetical concept that violate a number of essential physical principles.

when was dixon ticonderoga invented

1795 yoooooo

blade vortex interaction

A blade vortex interaction (BVI) is an unsteady phenomenon of three-dimensional nature, which occurs when a rotor blade passes within a close proximity of the shed tip vortices from a previous blade. This is why helicopter blades make so much noise.

tarantula molting can regrow limbs

A tarantula is able to regenerate a new leg the next time he molts. This new leg may not be as large or hairy as the previous one, but additional molting sessions will restore the leg to its normal appearance. Male tarantulas rarely molt again once they reach adulthood, but they may attempt to do so, usually becoming stuck during the molt due to their sexual organs and dying in the process. Females continue to molt after reaching maturity. Female specimens have been known to reach 30 to 40 years of age, and have survived on water alone for up to two years.

cuticle

A waxy covering on the surface of stems and leaves that acts as an adaptation to prevent desiccation in terrestrial plants. a protective and waxy or hard layer covering the epidermis of a plant, invertebrate, or shell.

Stochastic cooling

Stochastic cooling is a form of particle beam cooling. It is used in some particle accelerators and storage rings to control the emittance of the particle beams in the machine. By analogy with the kinetic theory of gases, where heat is equivalent to disorder, the term "cooling" here denotes the reduction of disorder in the beam. The focus of stochastic cooling is on reducing the amplitudes in the motion of particles in a beam in order to contain them in a restricted space and maintain their energies close to a mean value. The particles are thereby better organised and the beam is cooled.

Book lung

A book lung is a type of respiration organ used for atmospheric gas exchange that is present in many arachnids, such as scorpions and spiders. Each of these organs is located inside an open ventral abdominal, air-filled cavity (atrium) and connects with the surroundings through a small opening for the purpose of respiration. Book lungs are not related to the lungs of modern land-dwelling vertebrates. Their name describes their structure. Stacks of alternating air pockets and tissue filled with hemolymph give them an appearance similar to a "folded" book. Their number varies from just one pair in most spiders to four pairs in scorpions. The unfolded "pages" (plates) of the book lung are filled with hemolymph. The folds maximize the surface exposed to air, and thereby maximize the amount of gas exchanged with the environment. In most species, no motion of the plates is needed to facilitate this kind of respiration.

Big Bang Cooling: The universe continued to decrease in density and fall in temperature, hence the typical energy of each particle was decreasing. Symmetry breaking phase transitions put the fundamental forces of physics and the parameters of elementary particles into their present form, with the electromagnetic force and weak nuclear force separating at about 10^−12 seconds. After about 10^−11 seconds, the picture becomes less speculative, since particle energies drop to values that can be attained in particle accelerators. At about 10^−6 seconds, quarks and gluons combined to form baryons such as protons and neutrons. The small excess of quarks over antiquarks led to a small excess of baryons over antibaryons. The temperature was now no longer high enough to create new proton-antiproton pairs (similarly for neutrons-antineutrons), so a mass annihilation immediately followed, leaving just one in 10^10 of the original protons and neutrons, and none of their antiparticles. A similar process happened at about 1 second for electrons and positrons. After these annihilations, the remaining protons, neutrons and electrons were no longer moving relativistically and the energy density of the universe was dominated by photons (with a minor contribution from neutrinos).

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Fossils of very large dragonfly ancestors in the Protodonata are found from 325 million years ago (Mya) in Upper Carboniferous rocks; these had wingspans up to about 750 mm (30 in). There are about 3,000 extant species. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threatens dragonfly populations around the world. Dragonflies live on every continent except Antarctica.

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Hamsters can stuff up to 20% of their body weight into their cheeks.

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The authors report that bat-munching spiders live on every continent except Antarctica. Most catch bats in webs, like the giant golden silk orb-weavers (Nephilidae). As adults, these spiders' leg spans can be 10-15 centimeters across, and they weave webs more than a meter in diameter. Bats have also been observed in the webs of social spiders, such as Parawixia. But a minority of spiders, like huntsman and tarantulas, forage for prey without a web, and have been spotted munching on bats on forest floors.

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The female mosquito is the one that bites (males feed on flower nectar). She requires blood to produce eggs. Her mouthparts are constructed so that they pierce the skin, literally sucking the blood out. Her saliva lubricates the opening. It's the saliva plus the injury to the skin that creates the stinging and irritation we associate with mosquito bites.

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The job of technology is to free up humans from toil, drudgery, repetition, and nonsense.

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Human color vision is tri-chromatic, with three opsins expressed in cone photoreceptors that are sensitive in the red, green, and blue region of the spectrum. However, we discovered that dragonflies possess as many as 15-33 opsin genes that have evolved through dynamic gene multiplications and losses within the lineage of dragonflies. These opsin genes are differentially expressed between adult and larva, as well as between dorsal and ventral regions of adult compound eyes, which plausibly underpin the versatile behavioral and ecological adaptations of actively flying adults to aerial lifestyle and sedentary larvae to aquatic lifestyle. Dragonflies use different opsins at different ages. For instance, the larvae of some species that hatch in sand tend to lack blue opsins. "This is probably because blue light does not reach them easily," he says. Do all those extra opsins mean dragonflies see the rainbow differently to us? Probably. Other studies have found that dragonflies can see ultraviolet on top of blue, green and red. And it is thought that they can recognise polarised light coming off reflective surfaces like water. "It's likely that they have better colour discrimination than humans," says Futahashi.

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Machine Learning is the science and art of programming computers so they can learn from data.

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Permafrost soils contain roughly twice as much carbon - mainly in the form of methane and CO2 - as Earth's atmosphere. The thawing of the permafrost also threatens to unlock disease-causing bacteria and viruses long trapped in the ice.​ There have already been some cases of this happening. In 2016 a child died in Russia's far northern Siberia in an outbreak of anthrax that scientists said seemed to have come from the corpses of infected reindeers buried 70 years before but uncovered by melting permafrost. In 2014 scientists revived a giant but harmless virus, dubbed Pithovirus sibericum, that had been locked in the Siberian permafrost for more than 30,000 years.

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Pine needles are a natural mosquito repellent. Grab pine needles and break them apart until pine oil comes out and rub it on your body to repel mosquitoes.

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Planarians have unusual talents, to say the least. If you slice one of the tiny flatworms in half, the halves will grow back, giving you two identical worms. Cut a flatworm's head in two, and it will grow two heads. Cut an eye off a flatworm — it will grow back. Stick an eye on a flatworm that lacks eyes — it'll take root. Pieces as small as one-279th of a flatworm will turn into new, whole flatworms, given the time. The team looked more closely and realized that some of the regeneration-related cells were positioned at key branching points in the network of nerves between the worms' eyes and their brains. When the researchers transplanted an eye from one animal to another, the neurons growing from the new eye always grew toward these cells. When the nerve cells reached their target, they kept growing along the route that would take them to the brain. Removing those cells meant the neurons got lost and did not reach the brain. The cells seemed to be acting as guides of some kind. Guidepost cells that point the way for other cells play important roles in embryo development in many creatures, Dr. Reddien said. But by the time most animals grow into adults, these cells are usually long-gone. In flatworms, however, cells that perform this guiding role apparently exist in adults. They probably arrange themselves along the route from eye to brain using signals from muscle cells that tell them precisely where they should be in the body, Dr. Reddien said.

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Scientist at CERN report that the LHCb experiment has observed a four-charm quark particle never seen before, which is likely to be the first of a previously undiscovered class of particles.

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Scientists have only recently begun to quantify the microbiome, and discovered it is inhabited by at least 38 trillion bacteria. More intriguing, perhaps, is that bacteria are not the most abundant microbes that live in and on our bodies. That award goes to viruses. It has been estimated that there are over 380 trillion viruses inhabiting us, a community collectively known as the human virome. But these viruses are not the dangerous ones you commonly hear about, like those that cause the flu or the common cold, or more sinister infections like Ebola or dengue. Many of these viruses infect the bacteria that live inside you and are known as bacteriophages, or phages for short. The human body is a breeding ground for phages, and despite their abundance, we have very little insight into what all they or any of the other viruses in the body are doing. One might rightly assume that if viruses are the most abundant microbes in the body, they would be the target of the majority of human microbiome studies. But that assumption would be horribly wrong. The study of the human virome lags so far behind the study of bacteria that we are only just now uncovering some of their most basic features. This lag is due to it having taken scientists much longer to recognize the presence of a human virome, and a lack of standardized and sophisticated tools to decipher what's actually in your virome. Here's a few of the things we have learned thus far. Bacteria in the human body are not in love with their many phages that live in and around them. In fact they developed CRISPR-Cas systems - which humans have now co-opted for editing genes - to rid themselves of phages or to prevent phage infections altogether. Why? Because phages kill bacteria. They take over the bacteria's machinery and force them to make more phages rather than make more bacteria. When they are done, they burst out of the bacterium, destroying it. Finally, phages sit on our body surfaces just waiting to cross paths with vulnerable bacteria. They are basically bacteria stalkers. Viruses may inhabit all surfaces both inside and outside of the body. Everywhere researchers have looked in the human body, viruses have been found. Viruses in the blood? Check. Viruses on the skin? Check. Viruses in the lungs? Check. Viruses in the urine? Check. And so on. To put it simply, when it comes to where viruses live in the human body, figuring out where they don't live is a far better question than asking where they do.

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Some galaxies, however, lack any supermassive black holes in their centers. Although most galaxies with no supermassive black holes are very small, dwarf galaxies, one discovery remains mysterious: The supergiant elliptical cD galaxy A2261-BCG has not been found to contain an active supermassive black hole, despite the galaxy being one of the largest galaxies known; ten times the size and one thousand times the mass of the Milky Way. Since a supermassive black hole will only be visible while it is accreting, a supermassive black hole can be nearly invisible, except in its effects on stellar orbits. In December 2017, astronomers reported the detection of the most distant quasar currently known, ULAS J1342+0928, containing the most distant supermassive black hole, at a reported redshift of z = 7.54, surpassing the redshift of 7 for the previously known most distant quasar ULAS J1120+0641.

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The World Meteorological Organization announces new records for the longest lightning bolt (700 km) and the "megaflash" with the longest duration (16.73 s).

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The accelerated expansion of the universe is thought to have begun since the universe entered its dark-energy-dominated era roughly 4 billion years ago. Within the framework of general relativity, an accelerated expansion can be accounted for by a positive value of the cosmological constant Λ, equivalent to the presence of a positive vacuum energy, dubbed "dark energy". While there are alternative possible explanations, the description assuming dark energy (positive Λ) is used in the current standard model of cosmology, which also includes cold dark matter (CDM) and is known as the Lambda-CDM model.

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debt of any kind = mortgaging your future

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Dark galaxy

A dark galaxy is a hypothesized galaxy with no, or very few, stars. They received their name because they have no visible stars, but may be detectable if they contain significant amounts of gas. Astronomers have long theorized the existence of dark galaxies, but there are no confirmed examples to date. Dark galaxies are distinct from intergalactic gas clouds caused by galactic tidal interactions, since these gas clouds do not contain dark matter, so they do not technically qualify as galaxies. Distinguishing between intergalactic gas clouds and galaxies is difficult; most candidate dark galaxies turn out to be tidal gas clouds.[3] The best candidate dark galaxies to date include HI1225+01,[4] AGC229385,[5] and numerous gas clouds detected in studies of quasars. On 25 August 2016, astronomers reported that Dragonfly 44, an ultra diffuse galaxy (UDG) with the mass of the Milky Way galaxy, but with nearly no discernable stars or galactic structure, is made almost entirely of dark matter.

Gamma-ray laser

A gamma-ray laser, or graser, is a hypothetical device that would produce coherent gamma rays, just as an ordinary laser produces coherent rays of visible light. In his 2003 Nobel lecture, Vitaly Ginzburg cited the gamma-ray laser as one of the thirty most important problems in physics. The effort to construct a practical gamma-ray laser is interdisciplinary, encompassing quantum mechanics, nuclear and optical spectroscopy, chemistry, solid-state physics, and metallurgy—as well as the generation, moderation, and interaction of neutrons—and involves specialized knowledge and research in all these fields. The subject involves both basic science and engineering technology.

Hydrogen maser

A hydrogen maser, also known as hydrogen frequency standard, is a specific type of maser that uses the intrinsic properties of the hydrogen atom to serve as a precision frequency reference. Both the proton and electron of a hydrogen atom have spins. The atom has a higher energy if both are spinning in the same direction, and a lower energy if they spin in opposite directions. The amount of energy needed to reverse the spin of the electron is equivalent to a photon at the frequency of 1,420,405,751.786 Hz,[1] which corresponds to the 21 cm line in hydrogen spectrum. Hydrogen masers are very complex devices and sell for as much as US$235,000.[2] They are made in two types: active and passive.

Magnetosonic wave

A magnetosonic wave (also called magnetoacoustic wave) is a linear magnetohydrodynamic (MHD) wave that is driven by both pressure (thermal and magnetic) and magnetic tension. There are two types of magnetosonic waves, the fast magnetosonic wave and the slow magnetosonic wave. Both fast and slow magnetosonic waves have been recently discovered in the solar corona,[1] which created an observational foundation for the novel technique for the coronal plasma diagnostics, coronal seismology.

Mock execution

A mock execution is a stratagem in which a victim is deliberately but falsely made to feel that their execution or that of another person is imminent or is taking place.

Pentaquark

A pentaquark is a subatomic particle consisting of four quarks and one antiquark bound together. As quarks have a baryon number of +1/3, and antiquarks of −1/3, the pentaquark would have a total baryon number of 1, and thus would be a baryon.

Pheromone

A pheromone (from Ancient Greek φέρω phero "to bear" and hormone) is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to impact the behavior of the receiving individuals. There are alarm pheromones, food trail pheromones, sex pheromones, and many others that affect behavior or physiology. Most sex pheromones are produced by the females; only a small percentage of sex attractants are produced by males. Some species release a volatile substance when attacked by a predator that can trigger flight (in aphids) or aggression (in ants, bees, termites)[8] in members of the same species. Pheromones also exist in plants: Certain plants emit alarm pheromones when grazed upon, resulting in tannin production in neighboring plants. These tannins make the plants less appetizing for the herbivore.

Planarian

A planarian is one of many flatworms of the traditional class Turbellaria. It usually describes free-living flatworms of the order Tricladida (triclads), although this common name is also used for a wide number of free-living platyhelminthes.

Shape-memory alloy

A shape-memory alloy is an alloy that can be deformed when cold but returns to its pre-deformed ("remembered") shape when heated. Nitinol. The two most prevalent shape-memory alloys are copper-aluminium-nickel and nickel-titanium (NiTi), but SMAs can also be created by alloying zinc, copper, gold and iron. Although iron-based and copper-based SMAs, such as Fe-Mn-Si, Cu-Zn-Al and Cu-Al-Ni, are commercially available and cheaper than NiTi, NiTi-based SMAs are preferable for most applications due to their stability and practicability and superior thermo-mechanic performance.[4] SMAs can exist in two different phases, with three different crystal structures (i.e. twinned martensite, detwinned martensite and austenite) and six possible transformations.

how much pee can whale bladder fit

A single fin whale is thought to produce around 1,000 liters (260 gallons) of urine each day — enough to fill a 10-by-6-foot kiddie pool.

Spinneret

A spinneret is a silk-spinning organ of a spider or the larva of an insect. Some adult insects also have spinnerets, such as those borne on the forelegs of Embioptera.[1] Spinnerets are usually on the underside of a spider's abdomen, to the rear.[2] While most spiders have six spinnerets, some have two, four, or eight.[3] They can move both independently and in concert. Most spinnerets are not simple structures with a single orifice producing a single thread, but complex structures of many microscopic spigots, each producing one filament. This produces the necessary orientation of the protein molecules, without which the silk would be weak and useless. It also permits spiders to combine multiple filaments in different ways to produce many kinds of silk for various purposes. Various species of spiders use silk extruded from spinnerets to build webs, to transfer sperm, to entrap insects by wrapping it around them, to make egg-cases, to manipulate static electricity in the air and fly (ballooning), etc. Observations suggesting that there might be silk-producing organs on the feet of the zebra tarantula (Aphonopelma seemanni) led to questions about the origins of spinnerets. It was hypothesised that spinnerets in spiders were originally used as climbing aids on the feet and evolved and were used for webmaking at a later time.

Web decoration

A web decoration or stabilimentum (plural: stabilimenta) is a conspicuous silk structure included in the webs of some species of orb-web spider. Its function is a subject of debate. It is likely that the use of stabilimenta evolved independently at least nine different times. Originally the decorations were thought to stabilize the web (hence the term stabilimentum),[4] though this hypothesis has since been dismissed because it was found that the decoration is only loosely attached to the web so that the actual influence on the stability could be minor. Notable is the fact that stabilimentum-building spiders are largely diurnal.[6] It has been suggested that stabilimenta could provide protection to the spider by either camouflaging it (by breaking up its outline), or making it appear larger (by extending its outline).[7] Another hypothesis is that they make the web visible and therefore animals such as birds are less likely to damage the spider's web.[8] More recent work (2016) has leaned toward this latter hypothesis, further finding that food capture was reduced by their presence. The authors note that regardless of function, there is a high cost to building a stabilimentum, and therefore the benefit must be equally large. The other dominating hypothesis is that web decorations attract prey by reflecting ultraviolet light.[9] Light in the ultraviolet part of the spectrum is known to be attractive to many species of insects. Another hypothesis is that the purpose of the stabilimentum is to attract the male of the species to the web when the female is ready to reproduce. A limited study carried out in the Calahonda area of Spain in the summer of 1992 showed that there was a positive correlation between the presence of a male in the webs of Argiope lobata and the presence of a stabilimentum.[10][better source needed] It is claimed that E. B. White came up with the idea of a writing spider for his book Charlotte's Web after observing stabilimenta in a spider web.

25% helium after big bang, why?

After about 15 minutes from the Big Bang, the universe had expanded and cooled so much that fusion was no longer possible. The composition of the universe was 10% helium and 90% hydrogen (or if you use the proportions by mass, then the proportions are 25% helium and 75% hydrogen). Except for the extremely small amounts of the Lithium-7 produced in the early universe, the elements heavier than helium were produced in the cores of stars. Stars do produce some of the helium visible today, but not most of it. If all the helium present today was from stars, then the nuclear reaction rates would have to be extremely high and the galaxies should be much brighter than they are.

Ag-gag

Ag-gag laws are anti-whistleblower laws that apply within the agriculture industry. The term ag-gag typically refers to state laws in the United States of America that forbid undercover filming or photography of activity on farms without the consent of their owner—particularly targeting whistleblowers of animal rights abuses at these facilities.

Crazy lace agate

Agate is a common rock formation, consisting of chalcedony and quartz as its primary components,[1] consisting of a wide variety of colors. Agates are primarily formed within volcanic and metamorphic rocks. Decorative uses of agates are known to date back to Ancient Greece and are used most commonly as decorations or jewelry. Agate minerals have the tendency to form on or within pre-existing rocks, creating difficulties in accurately determining their time of formation. Agates are most commonly found as nodules within the cavities of volcanic rocks. These cavities are formed from the gases trapped within the liquid volcanic material forming vesicles.[6] Cavities are then filled in with silica-rich fluids from the volcanic[6] material, layers are deposited on the walls of the cavity slowly working their way inwards.[7] The first layer deposited on the cavity walls is commonly known as the priming layer.[8] Variations in the character of the solution or in the conditions of deposition may cause a corresponding variation in the successive layers. These variations in layers result in bands of chalcedony, often alternate with layers of crystalline quartz forming banded agate.[6] Hollow agates can also form due to the deposition of liquid-rich silica not penetrating deep enough to fill the cavity completely.[9] Agate will form crystals within the reduced cavity, the apex of each crystal may point towards the center of the cavity.

Respiratory system of insects

Air enters the respiratory systems of insects through a series of external openings called spiracles. These external openings, which act as muscular valves in some insects, lead to the internal respiratory system, a densely networked array of tubes called tracheae. This network of transverse and longitudinal tracheae equalizes pressure throughout the system. It is responsible for delivering sufficient oxygen (O2) to all cells of the body and for removing carbon dioxide (CO2) that is produced as a waste product of cellular respiration. The respiratory system of insects (and many other arthropods) is separate from the circulatory system. Image: Indian moon moth (Actias selene) with some of the spiracles identified. Insects have spiracles on their exoskeletons to allow air to enter the trachea.[1] In insects, the tracheal tubes primarily deliver oxygen directly into the insects' tissues. The spiracles can be opened and closed in an efficient manner to reduce water loss. This is done by contracting closer muscles surrounding the spiracle. In order to open, the muscle relaxes. The closer muscle is controlled by the central nervous system but can also react to localized chemical stimuli. Several aquatic insects have similar or alternative closing methods to prevent water from entering the trachea. Spiracles may also be surrounded by hairs to minimize bulk air movement around the opening, and thus minimize water loss. The spiracles are located laterally along the thorax and abdomen of most insects—usually one pair of spiracles per body segment. Air flow is regulated by small muscles that operate one or two flap-like valves within each spiracle—contracting to close the spiracle, or relaxing to open it. After passing through a spiracle, air enters a longitudinal tracheal trunk, eventually diffusing throughout a complex, branching network of tracheal tubes that subdivides into smaller and smaller diameters and reaches every part of the body. At the end of each tracheal branch, a special cell (the tracheole) provides a thin, moist interface for the exchange of gasses between atmospheric air and a living cell. Oxygen in the tracheal tube first dissolves in the liquid of the tracheole and then diffuses across the cell membrane into the cytoplasm of an adjacent cell. At the same time, carbon dioxide, produced as a waste product of cellular respiration, diffuses out of the cell and, eventually, out of the body through the tracheal system. Each tracheal tube develops as an invagination of the ectoderm during embryonic development. To prevent its collapse under pressure, a thin, reinforcing "wire" of cuticle (the taenidia) winds spirally through the membranous wall. This design (similar in structure to a heater hose on an automobile or an exhaust duct on a clothes dryer) gives tracheal tubes the ability to flex and stretch without developing kinks that might restrict air flow. The absence of taenidia in certain parts of the tracheal system allows the formation of collapsible air sacs, balloon-like structures that may store a reserve of air. In dry terrestrial environments, this temporary air supply allows an insect to conserve water by closing its spiracles during periods of high evaporative stress. Aquatic insects consume the stored air while under water or use it to regulate buoyancy. During a molt, air sacs fill and enlarge as the insect breaks free of the old exoskeleton and expands a new one. Between molts, the air sacs provide room for new growth—shrinking in volume as they are compressed by expansion of internal organs.

why do spiders make venom?

Almost all spiders, with only a few exceptions, produce venom, which serves the primary purpose of immobilising their prey. However, the content of this venom can vary wildly from species to species, and the majority are not harmful to humans. Spider venoms work on one of two fundamental principles; they are either neurotoxic (attacking the nervous system) or necrotic (attacking tissues surrounding the bite). In some cases, the venom affects vital organs and systems.

how strong are eagle talons?

An adult bald eagle's talons are 2 inches long and are capable of exerting a force of 1,000 pounds of pressure per square inch.

Neutrino decoupling

In Big Bang cosmology, neutrino decoupling was the epoch at which neutrinos ceased interacting with other types of matter [1], and thereby ceased influencing the dynamics of the universe at early times.[2] Prior to decoupling, neutrinos were in thermal equilibrium with protons, neutrons and electrons, which was maintained through the weak interaction. Decoupling occurred approximately at the time when the rate of those weak interactions was slower than the rate of expansion of the universe. Alternatively, it was the time when the time scale for weak interactions became greater than the age of the universe at that time. Neutrino decoupling took place approximately one second after the Big Bang, when the temperature of the universe was approximately 10 billion kelvins, or 1 MeV.[3]

Electron gun

An electron gun (also called electron emitter) is an electrical component in some vacuum tubes that produces a narrow, collimated electron beam that has a precise kinetic energy. The largest use is in cathode ray tubes (CRTs), used in nearly all television sets, computer displays and oscilloscopes that are not flat-panel displays. They are also used in field emission displays (FEDs), which are essentially flat-panel displays made out of rows of extremely small cathode ray tubes. They are also used in microwave linear beam vacuum tubes such as klystrons, inductive output tubes, travelling wave tubes, and gyrotrons, as well as in scientific instruments such as electron microscopes and particle accelerators. Electron guns may be classified by the type of electric field generation (DC or RF), by emission mechanism (thermionic, photocathode, cold emission, plasmas source), by focusing (pure electrostatic or with magnetic fields), or by the number of electrodes. A direct current, electrostatic thermionic electron gun is formed from several parts: a hot cathode, which is heated to create a stream of electrons via thermionic emission, electrodes generating an electric field to focus the electron beam (such as a Wehnelt cylinder), and one or more anode electrodes which accelerate and further focus the beam. A large voltage difference between the cathode and anode accelerates the electrons away from the cathode. A repulsive ring placed between the electrodes focuses the electrons onto a small spot on the anode, at the expense of a lower extraction field strength on the cathode surface. There is often a hole through the anode at this small spot, through which the electrons pass to form a collimated beam before reaching a second anode, called the collector. This arrangement is similar to an Einzel lens. Read This: Most color cathode ray tubes - such as those used in color televisions - incorporate three electron guns, each one producing a different stream of electrons. Each stream travels through a shadow mask where the electrons will impinge upon either a red, green or blue phosphor to light up a color pixel on the screen. The resultant color that is seen by the viewer will be a combination of these three primary colors.

Apophallation

Apophallation is the biting off of the penis, known in terrestrial slugs, which are hermaphroditic gastropod mollusks. It has been reported in some species of banana slugs Ariolimax and in the distantly related Deroceras laeve. In the mating of banana slugs, the penis is inserted into the body of the partner. The penis may become trapped, perhaps because of the action of a special muscle, in which case the penis is gnawed off by either the partner or the owner. No replacement penis grows, but the apophallated slug can mate as a female.[2] It has been proposed that preventing the partner from mating as a male might be adaptive in increasing its allocation of resources to the production of eggs. One paper reports that individuals of Deroceras laeve sometimes after mating bite off their own penis, which is then eaten by the partner.[3] In this genus, sperm is swapped from penis to penis, so the amputee would not be able to mate successfully even in the female role.[1]

Apotropaic magic

Apotropaic magic is a type of magic intended to turn away harm or evil influences, as in deflecting misfortune or averting the evil eye. Apotropaic observances may also be practiced out of vague superstition or out of tradition, as in good luck charms, amulets, or gestures such as crossed fingers or knocking on wood.

most money for conservation in america comes from hunting

As Wyoming grapples with how it will fund wildlife conservation, hunters may lose some of their influence as other groups and interests are asked to increase their financial contributions. Hunters have been key players in conserving wildlife in the post-frontier era, a development that's come to be called the North American Model of Wildlife Management. Wyoming Game and Fish Department says 55 percent of its budget comes from the sale of hunting and fishing licenses and fees, and that hunters contribute even more through taxes on guns and ammo.

do snails grow their shells?

As the snail grows, so does its calcium carbonate shell. The shell grows additively, by the addition of new calcium carbonate, which is secreted by glands located in the snail's mantle. The new material is added to the edge of the shell aperture (the opening of the shell).

Helicobacter pylori (H. pylori)

Bacterium found in GI tract of 90% of patients with duodenal ulcers and 70% of those with gastric ulcers First-line therapy includes a 10- to 14-day course of a proton pump inhibitor and antibiotics. Helicobacter pylori, is a helically-shaped, microaerophilic bacterium usually found in the stomach.[7] Its helical shape (from which the genus name, helicobacter, derives) is thought to have evolved in order to penetrate the mucoid lining of the stomach and thereby establish infection. A peptic ulcer is a sore on the lining of the stomach or duodenum, which is the beginning of the small intestine. The H. pylori bacteria weakens the protective mucous coating of the stomach and duodenum, thus allowing acid to get through to the sensitive lining beneath. Both the acid and the bacteria irritate the lining and cause a sore, or ulcer. H. pylori is able to survive in stomach acid because it secretes enzymes that neutralize the acid. This mechanism allows H. pylori to make its way to the "safe" area - the protective mucous lining. Once there, the bacterium's spiral shape helps it burrow through the lining.

Ballooning (spider)

Ballooning, sometimes called kiting, is a process by which spiders, and some other small invertebrates, move through the air by releasing one or more gossamer threads to catch the wind, causing them to become airborne at the mercy of air currents and potentially electric currents. This is primarily used by spiderlings to disperse; however, larger individuals have been observed doing so as well. The spider climbs to a high point and takes a stance with its abdomen to the sky, releasing fine silk threads from its spinneret until it becomes aloft. Journeys achieved vary from a few metres to hundreds of kilometres. Even atmospheric samples collected from balloons at five kilometres altitude and ships mid-ocean have reported spider landings. Mortality is high. It is observed in many species of spiders, as well as in spider mites ( Tetranychidae ) and in 31 species of lepidoptera, distributed in 8 suborders. Bell and his colleagues put forward the hypothesis that ballooning first appeared in the Cretaceous.

Parawixia

Bats have also been observed in the webs of social spiders, such as Parawixia. But a minority of spiders, like huntsman and tarantulas, forage for prey without a web, and have been spotted munching on bats on forest floors

blind ambition

Blind ambition is when ambition prevents people from seeing what's happening around them. Sometimes blind ambition is a great trait to have too. Sometimes we need to block out what is happening around us in order to do what seems impossible.

Stellarator

In a stellarator the magnetic cage is produced with a single coil system - without a longitudinal net-current in the plasma and hence without a transformer. This makes stellarators suitable for continuous operation, whereas tokamaks without auxiliary facilities operate in pulsed mode.

Bombardier beetle

Bombardier beetles are ground beetles (Carabidae) in the tribes Brachinini, Paussini, Ozaenini, or Metriini—more than 500 species altogether—which are most notable for the defense mechanism that gives them their name: when disturbed, they eject a hot noxious chemical spray from the tip of the abdomen with a popping sound. The spray is produced from a reaction between two chemical compounds, hydroquinone and hydrogen peroxide, which are stored in two reservoirs in the beetle's abdomen. When the aqueous solution of hydroquinones and hydrogen peroxide reaches the vestibule, catalysts facilitate the decomposition of the hydrogen peroxide and the oxidation of the hydroquinone.[1] Heat from the reaction brings the mixture to near the boiling point of water and produces gas that drives the ejection. The damage caused can be fatal to attacking insects. Some bombardier beetles can direct the spray in a wide range of directions. This reaction is very exothermic, and the released energy raises the temperature of the mixture to near 100 °C, vaporizing about a fifth of it. The resultant pressure buildup forces the entrance valves from the reactant storage chambers to close, thus protecting the beetle's internal organs. The boiling, foul-smelling liquid is expelled violently through an outlet valve, with a loud popping sound. The beetles' glands store enough hydroquinone and hydrogen peroxide to allow the beetle to release its chemical spray roughly 20 times. In some cases this is enough to kill a predator.[6] The main component of the beetle spray is 1,4-benzoquinone, an irritant to the eyes and the respiratory system of vertebrates. The flow of reactants into the reaction chamber and subsequent ejection occur in a series of about 70 pulses, at a rate of about 500 pulses per second. The whole sequence of events takes only a fraction of a second. These pulsations are caused by repeated microexplosions which are the results of the continuous pressure on the reservoir and the oscillatory opening and closing of the valve that controls access to the reaction chamber. This pulsed mechanism is beneficial for the beetles' survival because the system uses pressure instead of muscles to eject the spray at a constant velocity, saving the beetle energy. Also, the reintroduction of new reactants into the vestibule where enzymes are stored, reduces the temperature of the chamber, thereby protecting the peroxidases and catalases from thermal denaturation.[7] Typically the beetle turns its body so as to direct the jet towards whatever triggered the response. The gland openings of some African bombardier beetles can swivel through 270° and thrust between the insect's legs, discharging the fluid in a wide range of directions with considerable accuracy.[8]

CP-symmetry

CP-symmetry states that the laws of physics should be the same if a particle is interchanged with its antiparticle (C symmetry) while its spatial coordinates are inverted ("mirror" or P symmetry). In 1957 Wu, E. Ambler, R. W. Hayward, D. D. Hoppes, and R. P. Hudson found a clear violation of parity conservation in the beta decay of cobalt-60.

electrons behave like bosons in superconductors

Conventional superconductors, electrons overcome their mutual repulsion to form 'Cooper pairs', which are propelled through the superconductor by lattice vibrations known as phonons. Now Samuelsson and Büttiker say that these pairs of electrons could show the positive correlation usually associated with bosons. The researchers propose a set-up in which a quantum dot is connected to two normal conductors and a superconductor. An applied voltage would propel electrons into the normal conductors from the superconductor. But due to the 'proximity effect' - in which a superconductor induces superconductivity in an adjacent conductor - the electrons would travel across the quantum dot not singly, but in pairs. Samuelsson and Büttiker calculated the currents that would flow from the quantum dot into the normal conductors, and found a positive correlation similar to that originally observed in the split beam of photons. This suggests that some of the pairs would split up when they reached the normal conductors, with one electron entering each conductor. This would show that the pairs of electrons behave as bosons, even though single electrons are fermions.

Baryon acoustic oscillations (BAO)

In cosmology, baryon acoustic oscillations (BAO) are fluctuations in the density of the visible baryonic matter (normal matter) of the universe, caused by acoustic density waves in the primordial plasma of the early universe. In the same way that supernovae provide a "standard candle" for astronomical observations,[1] BAO matter clustering provides a "standard ruler" for length scale in cosmology. The length of this standard ruler is given by the maximum distance the acoustic waves could travel in the primordial plasma before the plasma cooled to the point where it became neutral atoms (the epoch of recombination), which stopped the expansion of the plasma density waves, "freezing" them into place. The length of this standard ruler (≈490 million light years in today's universe) can be measured by looking at the large scale structure of matter using astronomical surveys.

Cosmic ray

Cosmic rays are high-energy protons and atomic nuclei which move through space at nearly the speed of light. They originate from the sun, from outside of the solar system,[1] and from distant galaxies.[2] Upon impact with the Earth's atmosphere, cosmic rays can produce showers of secondary particles that sometimes reach the surface. Data from the Fermi Space Telescope (2013)[3] have been interpreted as evidence that a significant fraction of primary cosmic rays originate from the supernova explosions of stars.[4] Active galactic nuclei also appear to produce cosmic rays, based on observations of neutrinos and gamma rays from blazar TXS 0506+056 in 2018. Primary cosmic rays mostly originate from outside the Solar System and sometimes even the Milky Way. When they interact with Earth's atmosphere, they are converted to secondary particles. The mass ratio of helium to hydrogen nuclei, 28%, is similar to the primordial elemental abundance ratio of these elements, 24%. The remaining fraction is made up of the other heavier nuclei that are typical nucleosynthesis end products, primarily lithium, beryllium, and boron. These nuclei appear in cosmic rays in much greater abundance (≈1%) than in the solar atmosphere, where they are only about 10−11 as abundant as helium. Cosmic rays made up of charged nuclei heavier than helium are called HZE ions. Due to the high charge and heavy nature of HZE ions, their contribution to an astronaut's radiation dose in space is significant even though they are relatively scarce. Secondary Cosmic Rays: When cosmic rays enter the Earth's atmosphere they collide with atoms and molecules, mainly oxygen and nitrogen. The interaction produces a cascade of lighter particles, a so-called air shower secondary radiation that rains down, including x-rays, protons, alpha particles, pions, muons, electrons, neutrinos, and neutrons. All of the secondary particles produced by the collision continue onward on paths within about one degree of the primary particle's original path. Typical particles produced in such collisions are neutrons and charged mesons such as positive or negative pions and kaons. Some of these subsequently decay into muons and neutrinos, which are able to reach the surface of the Earth. Some high-energy muons even penetrate for some distance into shallow mines, and most neutrinos traverse the Earth without further interaction. Others decay into photons, subsequently producing electromagnetic cascades. Hence, next to photons electrons and positrons usually dominate in air showers. These particles as well as muons can be easily detected by many types of particle detectors, such as cloud chambers, bubble chambers, water-Cherenkov or scintillation detectors. The observation of a secondary shower of particles in multiple detectors at the same time is an indication that all of the particles came from that event.

cytotoxin

Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom.

Diadasia

Diadasia is a genus of bees in family Apidae. Species of Diadasia are oligolectic, specialized on a relatively small number of plant species. Their host plants include asters, bindweeds, cacti, mallows, and willowherbs, although mallows are the most common and likely ancestral host plant for the whole genus. Its tribe is Emphorini.[1] In the Sonoran Desert, Diadasia rinconis is considered the "cactus bee" as it feeds almost exclusively on a number of Sonoran Desert cactus species, its life cycle revolving around the flowering of the native species of cacti.

Dolomedes

Dolomedes is a genus of large spiders of the family Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all Dolomedes species are semiaquatic, with the exception of the tree-dwelling D. albineus of the southeastern United States. Many species have a striking pale stripe down each side of the body. They hunt by waiting at the edge of a pool or stream, then when they detect the ripples from prey, they run across the surface to subdue it using their foremost legs, which are tipped with small claws; like other spiders they then inject venom with their hollow jaws to kill and digest the prey. They mainly eat insects, but some larger species are able to catch small fish. They can also climb beneath the water, when they become encased in a silvery film of air. "Dolomedes" is derived from the Greek word "δολομήδης" which means wily, deceitful. Spiders are traditionally viewed as predators of insects, but a new study suggests that eating fish is widespread among species that live near water. There are over a hundred species of Dolomedes throughout the world.

Eastern equine encephalitis

Eastern equine encephalitis (EEE), commonly called Triple E, is a disease caused by a zoonotic mosquito vectored Togavirus that is present in North, Central, and South America, and the Caribbean. EEE was first recognized in Massachusetts, United States, in 1831, when 75 horses died mysteriously of viral encephalitis. The causative agent, later identified as a togavirus, was first isolated from infected horse brains in 1933. In 1938, the first confirmed human cases were identified when 30 children died of encephalitis in the Northeastern United States. These cases coincided with outbreaks in horses in the same regions. The fatality rate in humans is 33%, and currently no cure is known for human infections. This virus has four variations in the types in lineage. The most common to the human disease is group 1, which is considered to be endemic in North America and the Caribbean, while the other three lineages, groups IIA, IIB, and III, are typically found in Central and South America, causing equine illness.[2]

Aerogels against electromagnetic radiation

Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic components or the transmission of signals. High-frequency electromagnetic fields can only be shielded with conductive shells that are closed on all sides. Often thin metal sheets or metallized foils are used for this purpose. However, for many applications such a shield is too heavy or too poorly adaptable to the given geometry. The ideal solution would be a light, flexible and durable material with extremely high shielding effectiveness. The researchers are using nanofibers of cellulose as the basis for an aerogel, which is a light, highly porous material. Cellulose fibers are obtained from wood and, due to their chemical structure, enable a wide range of chemical modifications. They are therefore a highly popular research object. The crucial factor in the processing and modification of these cellulose nanofibres is to be able to produce certain microstructures in a defined way and to interpret the effects achieved. The researchers have succeeded in producing a composite of cellulose nanofibers and silver nanowires, and thereby created ultra-light fine structures which provide excellent shielding against electromagnetic radiation. The effect of the material is impressive: with a density of only 1.7 milligrams per cubic centimeter, the silver-reinforced cellulose aerogel achieves more than 40 dB shielding in the frequency range of high-resolution radar radiation (8 to 12 GHz) - in other words: Virtually all radiation in this frequency range is intercepted by the material.

Galaxy filament

In physical cosmology, galaxy filaments (subtypes: supercluster complexes, galaxy walls, and galaxy sheets) are the largest known structures in the universe. They are massive, thread-like formations, with a typical length of 50 to 80 megaparsecs h−1 (or of the order of 200 to 500 million light-years) that form the boundaries between large voids in the universe.[3] Filaments consist of gravitationally bound galaxies. Parts wherein many galaxies are very close to one another (in cosmic terms) are called superclusters. In the standard model of the evolution of the universe, galactic filaments form along and follow web-like strings of dark matter.[4] It is thought that this dark matter dictates the structure of the Universe on the grandest of scales. Dark matter gravitationally attracts baryonic matter, and it is this "normal" matter that astronomers see forming long, thin walls of super-galactic clusters.

Electron capture

Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shell. This process thereby changes a nuclear proton to a neutron and simultaneously causes the emission of an electron neutrino. The electron capture which causes potassium 40 to transform into argon 40 in its ground state takes place in only 0.04% of cases

Electron paramagnetic resonance

Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials with unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but it is electron spins that are excited instead of the spins of atomic nuclei.

Environmental DNA (eDNA)

Environmental DNA or eDNA is DNA that is collected from a variety of environmental samples such as soil, seawater, snow or even air [1] rather than directly sampled from an individual organism. As various organisms interact with the environment, DNA is expelled and accumulates in their surroundings. Example sources of eDNA include, but are not limited to, feces, mucus, gametes, shed skin, carcasses and hair. Such samples can be analyzed by high-throughput DNA sequencing methods, known as metagenomics, metabarcoding, and single-species detection[3], for rapid measurement and monitoring of biodiversity. In order to better differentiate between organisms within a sample, DNA metabarcoding is used in which the sample is analyzed and uses previously studied DNA libraries to determine what organisms are present (e.g. BLAST).[4] The analysis of eDNA has great potential, not only for monitoring common species, but to genetically detect and identify other extant species that could influence conservation efforts.

brannock device

Even the United States military used the Brannock Device. In 1933, a captain in the Navy told a shoe salesman that many of his sailors had foot problems. The salesman measured the sailors' feet with the Brannock Device and realized that the sailors were wearing the wrong size shoes! Once the sailors had the correct sizes, their foot troubles went away. By World War II, the Brannock Device was used by most of the armed forces.

On shell and off shell

In physics, particularly in quantum field theory, configurations of a physical system that satisfy classical equations of motion are called "on the mass shell" or simply more often on shell; while those that do not are called "off the mass shell", or off shell. In quantum field theory, virtual particles are termed off shell because they do not satisfy the energy-momentum relation; real exchange particles do satisfy this relation and are termed on shell (mass shell).

Mean free path

In physics, the mean free path is the average distance travelled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions), which modifies its direction or energy or other particle properties.

Folding@home

Folding@home is one of the world's fastest computing systems. With heightened interest in the project as a result of the COVID-19 pandemic,[7] the system achieved a speed of approximately 1.22 exaflops by late March 2020 and reaching 2.43 exaflops by April 12, 2020,[8] making it the world's first exaflop computing system. This level of performance from its large-scale computing network has allowed researchers to run computationally costly atomic-level simulations of protein folding thousands of times longer than formerly achieved. Since its launch on October 1, 2000, the Pande Lab has produced 223 scientific research papers as a direct result of Folding@home.[9] Results from the project's simulations agree well with experiments.[10][11][12] The project uses statistical simulation methodology that is a paradigm shift from traditional computing methods.[6] As part of the client-server model network architecture, the volunteered machines each receive pieces of a simulation (work units), complete them, and return them to the project's database servers, where the units are compiled into an overall simulation. Volunteers can track their contributions on the Folding@home website, which makes volunteers' participation competitive and encourages long-term involvement.

who made cuckoo clocks?

For a long time, the cuckoo clock was attributed to Franz Anton Ketterer, a clockmaker of some repute from the Black Forest village of Schönwald. It was believed that Ketterer created the cuckoo in the 1730s, inspired by the bellows of church organs to adapt the technology in lieu of the chimes then typically used in clocks.

Free molecular flow

Free molecular flow describes the fluid dynamics of gas where the mean free path of the molecules is larger than the size of the chamber or of the object under test. For tubes/objects of the size of several cm, this means pressures well below 10−3 mbar. This is also called the regime of high vacuum, or even ultra-high vacuum. This is opposed to viscous flow encountered at higher pressures Read This: In free molecular flow, the pressure of the remaining gas can be considered as effectively zero. Thus, boiling points do not depend on the residual pressure. The flow can be considered to be individual particles moving in straight lines. Practically, the "vapor" cannot move around bends or into other spaces behind obstacles, as they simply hit the tube wall. This implies conventional pumps cannot be used, as they rely on viscous flow and fluid pressure. Instead, special sorption pumps, ion pumps and momentum transfer pumps are used. Free molecular flow occurs in various processes such as molecular distillation, ultra-high vacuum equipment such as particle accelerators, and naturally in outer space.

Ionization gauge

Ionization gauges are the most sensitive gauges for very low pressures (also referred to as hard or high vacuum). They sense pressure indirectly by measuring the electrical ions produced when the gas is bombarded with electrons. Fewer ions will be produced by lower density gases. The calibration of an ion gauge is unstable and dependent on the nature of the gases being measured, which is not always known. They can be calibrated against a McLeod gauge which is much more stable and independent of gas chemistry. Thermionic emission generates electrons, which collide with gas atoms and generate positive ions. The ions are attracted to a suitably biased electrode known as the collector. The current in the collector is proportional to the rate of ionization, which is a function of the pressure in the system. Hence, measuring the collector current gives the gas pressure. There are several sub-types of ionization gauge.

Tantalum

The major use for tantalum, as the metal powder, is in the production of electronic components, mainly capacitors and some high-power resistors. Tantalum electrolytic capacitors exploit the tendency of tantalum to form a protective oxide surface layer, using tantalum powder, pressed into a pellet shape, as one "plate" of the capacitor, the oxide as the dielectric, and an electrolytic solution or conductive solid as the other "plate". Because the dielectric layer can be very thin (thinner than the similar layer in, for instance, an aluminium electrolytic capacitor), a high capacitance can be achieved in a small volume. Because of the size and weight advantages, tantalum capacitors are attractive for portable telephones, personal computers, automotive electronics and cameras.

HZE ions

HZE ions are the high-energy nuclei component of galactic cosmic rays (GCRs) which have an electric charge greater than +2. The abbreviation "HZE" comes from high (H) atomic number (Z) and energy (E). HZE ions include the nuclei of all elements heavier than hydrogen (which has a +1 charge) and helium (which has a +2 charge). Each HZE ion consists of a nucleus with no orbiting electrons, meaning that the charge on the ion is the same as the atomic number of the nucleus. HZE ions are rare compared to protons, for example, composing only 1% of GCRs versus 85% for protons.[1] HZE ions, like other GCRs, travel near the speed of light. Their source is likely to be supernova explosions. Although HZE ions make up a small proportion of cosmic rays, their high charge and high energies cause them to contribute significantly to the overall biological impact of cosmic rays, making them as significant as protons in regard to biological impact. The most dangerous GCRs are heavy ionized nuclei such as Fe +26, an iron nucleus with a charge of +26. Such heavy particles are "much more energetic (millions of MeV) than typical protons accelerated by solar flares (tens to hundreds of MeV)". HZE ions can therefore penetrate through thick layers of shielding and body tissue, "breaking the strands of DNA molecules, damaging genes and killing cells".

hail

Hail becomes an increasingly infrequent occurrence when the freezing level within the atmosphere exceeds 3,400 m (11,000 ft) above ground level. Hail forms in strong thunderstorm clouds, particularly those with intense updrafts, high liquid water content, great vertical extent, large water droplets, and where a good portion of the cloud layer is below freezing 0 °C (32 °F).[3] These types of strong updrafts can also indicate the presence of a tornado.[9] The growth rate of hailstones is impacted by factors such as higher elevation, lower freezing zones, and wind shear.

Hemolymph

Hemolymph, or haemolymph, is a fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod body remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which hemolymph cells called hemocytes are suspended. In addition to hemocytes, the plasma also contains many chemicals. It is the major tissue type of the open circulatory system characteristic of arthropods (e.g. arachnids, crustaceans and insects). In addition, some non-arthropods such as molluscs possess a hemolymphatic circulatory system. The blood-brain barrier is an evolutionary ancient structure that provides direct support and protection of the nervous system. In all systems, it establishes a tight diffusion barrier that hinders uncontrolled paracellular diffusion into the nervous system. In invertebrates, the blood-brain barrier separates the nervous system from the hemolymph. Thus, the barrier-forming cells need to actively import ions and nutrients into the nervous system. Method of transport In the grasshopper, the closed portion of the system consists of tubular hearts and an aorta running along the dorsal side of the insect. The hearts pump hemolymph into the sinuses of the hemocoel where exchanges of materials take place. The volume of hemolymph needed for such a system is kept to a minimum by a reduction in the size of the body cavity. The hemocoel is divided into chambers called sinuses. Coordinated movements of the body muscles gradually bring the hemolymph back to the dorsal sinus surrounding the hearts. Between contractions, tiny valves in the wall of the hearts open and allow hemolymph to enter. Hemolymph fills all of the interior (the hemocoel) of the animal's body and surrounds all cells. It contains hemocyanin, a copper-based protein that turns blue when oxygenated, instead of the iron-based hemoglobin in red blood cells found in vertebrates, giving hemolymph a blue-green color rather than the red color of vertebrate blood. When not oxygenated, hemolymph quickly loses its color and appears grey. The hemolymph of lower arthropods, including most insects, is not used for oxygen transport because these animals respirate through other means, such as tracheas, but it does contain nutrients such as proteins and sugars. Muscular movements by the animal during locomotion can facilitate hemolymph movement, but diverting flow from one area to another is limited. When the heart relaxes, blood is drawn back toward the heart through open-ended pores called ostia.[5] Note that the term "ostia" is not specific to insect circulation; it literally means "doors" or "openings", and must be understood in context.

Majorana fermion

In 1937, the Italian theoretical physicist Ettore Majorana hypothesized the existence of a unique particle that is its own antiparticle. This particle, also referred to as a "Majorana fermion," can also exist as a "quasiparticle," a collective phenomenon that behaves like an individual particle, as in waves forming on the water. Neutrinos may be majorana particles. With the exception of the neutrino, all of the Standard Model fermions are known to behave as Dirac fermions at low energy (after electroweak symmetry breaking), and none are Majorana fermions. The nature of the neutrinos is not settled—they may be either Dirac or Majorana fermions.

Acacias use ants to guard flowers

In Africa and in the tropics, armies of tiny creatures make the twisting stems of acacia plants their homes. Aggressive, stinging ants feed on the sugary nectar the plant provides and live in nests protected by its thick bark. This is the world of "ant guards". The acacias might appear overrun by them, but the plants have the ants wrapped around their little stems. These same plants that provide shelter and produce nourishing nectar to feed the insects also make chemicals that send them into a defensive frenzy, forcing them into retreat. Sweden have been trying to work out some of the ways in which the insects and the acacias might have co-evolved. He explains how the ants provide a useful service for the acacias. "They guard the plants they live on," said Dr Raine. "If other animals try to come and feed on the rich, sugary nectar, they will attack them."

Is the higgs boson inherently unstable or does it just decay fast since the temperature and pressure are not right?

When we say quarks and leptons interact with the higgs field, what is going on? Are higgs bosons constantly interacting with the quarks and leptons within atoms? What does it mean for them to "interact"? AHHHHHHHHH

underground civilization on mars

Would block radiation, help retain heat, and could implement a hyperloop. Just need to come up with a self assembling autonomous boring rig.

Open circulatory system

In arthropods, the open circulatory system is a system in which a fluid in a cavity called the hemocoel bathes the organs directly with oxygen and nutrients and there is no distinction between blood and interstitial fluid; this combined fluid is called hemolymph or haemolymph.[15] Muscular movements by the animal during locomotion can facilitate hemolymph movement, but diverting flow from one area to another is limited. When the heart relaxes, blood is drawn back toward the heart through open-ended pores (ostia). Hemolymph fills all of the interior hemocoel of the body and surrounds all cells. Hemolymph is composed of water, inorganic salts (mostly sodium, chloride, potassium, magnesium, and calcium), and organic compounds (mostly carbohydrates, proteins, and lipids). The primary oxygen transporter molecule is hemocyanin. There are free-floating cells, the hemocytes, within the hemolymph. They play a role in the arthropod immune system.

Baryonic dark matter

In astronomy and cosmology, baryonic dark matter is dark matter composed of baryons. Only a small proportion of the dark matter in the universe is likely to be baryonic.

Free streaming

In astronomy, a free streaming particle, often a photon, is one that propagates through a medium without scattering.

Hyperfine structure

In atomic physics, hyperfine structure is defined by small shifts and splittings in the energy levels of atoms, molecules, and ions, due to interaction between the state of the nucleus and the state of the electron clouds. In atoms, hyperfine structure arises from the energy of the nuclear magnetic dipole moment interacting with the magnetic field generated by the electrons and the energy of the nuclear electric quadrupole moment in the electric field gradient due to the distribution of charge within the atom. Molecular hyperfine structure is generally dominated by these two effects, but also includes the energy associated with the interaction between the magnetic moments associated with different magnetic nuclei in a molecule, as well as between the nuclear magnetic moments and the magnetic field generated by the rotation of the molecule. Hyperfine structure contrasts with fine structure, which results from the interaction between the magnetic moments associated with electron spin and the electrons' orbital angular momentum. Hyperfine structure, with energy shifts typically orders of magnitudes smaller than those of a fine-structure shift, results from the interactions of the nucleus (or nuclei, in molecules) with internally generated electric and magnetic fields. duh

Autolysis

In biology, autolysis, more commonly known as self-digestion, refers to the destruction of a cell through the action of its own enzymes. It may also refer to the digestion of an enzyme by another molecule of the same enzyme. Autolytic cell destruction is uncommon in living adult organisms and usually occurs in injured cells and dying tissue. Autolysis is initiated by the cells' lysosomes releasing digestive enzymes into the cytoplasm. These enzymes are released due to the cessation of active processes in the cell, not as an active process.

Goliath birdeater

The Goliath birdeater belongs to the tarantula family Theraphosidae. Found in northern South America, it is the largest spider in the world by mass and size, but it is second to the giant huntsman spider by leg span. It is also called the Goliath bird-eating spider; the practice of calling theraphosids "bird-eating" derives from an early 18th-century copper engraving by Maria Sibylla Merian that shows one eating a hummingbird. Despite the spider's name, it only rarely preys on birds. As its name suggests, this species can eat birds and just about anything that is smaller than it is, including invertebrates and mice, frogs, lizards and birds. At the Smithsonian's National Zoo, they eat cockroaches. The Goliath bird-eating spider is generally solitary, and individuals only come together to mate.

When we say quarks and leptons interact with the Higgs field, what is going on? Are Higgs bosons constantly interacting with the quarks and leptons within atoms? What does it mean for them to "interact"?

It's somewhat analogous to the way a charged particle interacts with an electrical potential field. The potential energy of a charged particle is its electric charge times the value of the potential field. The charge is the particle's "coupling" to the potential field. Likewise, some particles have a coupling to the Higgs field, so they have more energy when sitting in a non-zero Higgs field than they would in a zero Higgs field. But what makes the Higgs field special is that it has a non-zero expectation value in its "ground state", which is the state of the Higgs field when no Higgs bosons are present. That means that all particles with any coupling to the Higgs field will always have some minimum energy — in other words, mass.

Jack (baboon)

Jack (died 1890) was a chacma baboon who attained some fame for acting as an assistant to a disabled railway signalman in South Africa. Jack was the pet and assistant of double leg amputee signalman James Wide, who worked for the Cape Town-Port Elizabeth Railway service. James "Jumper" Wide had been known for jumping between railcars until an accident where he fell and lost both of his legs.[2] To assist in performing his duties, Wide purchased the baboon named Jack in 1881, and trained him to push his wheelchair and to operate the railways signals under supervision. After initial skepticism, the railway decided to officially employ Jack once his job competency was verified. The baboon was paid twenty cents a day, and half a bottle of beer each week. It is widely reported that in his nine years of employment with the railway company, Jack never made a single mistake.

Jeanne de Clisson

Jeanne de Clisson (1300-1359), was a Breton former noblewoman who became a privateer to avenge her husband after he was executed for treason by the French king. She plied the English Channel and targeted French ships, often slaughtering the crew. It was her practice to leave at least one sailor alive to carry her messages to the King of France.

Jumping spider

Jumping spiders are a group of spiders that constitute the family Salticidae. As of 2019, this family contained over 600 described genera and over 6000 described species, making it the largest family of spiders at 13% of all species. Jumping spiders have some of the best vision among arthropods and use it in courtship, hunting, and navigation. Although they normally move unobtrusively and fairly slowly, most species are capable of very agile jumps, notably when hunting, but sometimes in response to sudden threats or crossing long gaps. Jumping spiders can leap more than 20 times their own body length, propelled by their back legs. However, when pouncing on their prey, they make shorter, more accurate leaps. Both their book lungs and tracheal system are well-developed, and they use both systems (bimodal breathing). Jumping spiders are generally recognized by their eye pattern. All jumping spiders have four pairs of eyes, with the anterior median pair being particularly large. Jumping spiders live in a variety of habitats. Tropical forests harbor the most species, but they are also found in temperate forests, scrubland, deserts, intertidal zones, and mountainous regions. Euophrys omnisuperstes is the species reported to have been collected at the highest elevation, on the slopes of Mount Everest.

daddy long leg is a venomous spider

Just one touch of their venom in the bloodstream would kill a full grown man in minutes. The only reason they are harmless is because their fangs are unable to penetrate human skin.

Kumimanu

Kumimanu biceae is an extinct species of giant penguin, which lived around 60 to 56 million years ago. Standing approximately five feet and three to ten inches (1.60 to 1.77m) tall, and weighing over two hundred pounds (91 kg), being thus the second largest penguin thus far known.

laguna agate

Laguna Agate is the most highly praised banded agate in the world. It is known for its extremely tight banding and vibrant shades of red and scarlet. Laguna Agate is found in an area covering roughly four square miles in a remote mountain range in the state of Chihuahua, Mexico.

How do pelicans digest fish if they don't have teeth to chew it?

Many birds eat mostly seeds, which are tougher than fish. Birds have gizzards, a very muscular "second stomach" that grinds up food after the initial treatment with acid and enzymes in the "first stomach" (proventriculus). In many birds, the gizzard contains stones or grit that have been swallowed, and these provide extra grinding power. I don't know if pelicans usually have these gastroliths, as they're called, or not.

what is in an inhaler

Many inhalers contain steroids -- like prednisone -- to treat inflammation. Others have a type of drug called a bronchodilator to open up your airways. Some have both -- this is known as a combination inhaler. Common inhaled medications used for treatment of asthma are salbutamol, corticosteroids, and salmeterol.

What is the purpose of an animal's tail?

Many land animals use their tails to brush away flies and other biting insects. Some species, including cats and kangaroos, use their tails for balance; and some, such as New World monkeys and opossums, have what are known as prehensile tails, which are adapted to allow them to grasp tree branches.

Dirac equation

Matrix form of the Schrodinger Equation In particle physics, the Dirac equation is a relativistic wave equation derived by British physicist Paul Dirac in 1928. In its free form, or including electromagnetic interactions, it describes all spin-1/2 massive particles such as electrons and quarks for which parity is a symmetry. It is consistent with both the principles of quantum mechanics and the theory of special relativity, and was the first theory to account fully for special relativity in the context of quantum mechanics. It was validated by accounting for the fine details of the hydrogen spectrum in a completely rigorous way. The equation also implied the existence of a new form of matter, antimatter, previously unsuspected and unobserved and which was experimentally confirmed several years later.

Klystron

Microwave amplifier (vs. microwave generator like magnetron). Requires low-power microwave oscillator to energize it. Amplifies through velocity modulation. A klystron is a specialized linear-beam vacuum tube, invented in 1937 by American electrical engineers Russell and Sigurd Varian,[1] which is used as an amplifier for high radio frequencies, from UHF up into the microwave range. Low-power klystrons are used as oscillators in terrestrial microwave relay communications links, while high-power klystrons are used as output tubes in UHF television transmitters, satellite communication, radar transmitters, and to generate the drive power for modern particle accelerators. In a klystron, an electron beam interacts with radio waves as it passes through resonant cavities, metal boxes along the length of a tube.[2] The electron beam first passes through a cavity to which the input signal is applied. The energy of the electron beam amplifies the signal, and the amplified signal is taken from a cavity at the other end of the tube. The output signal can be coupled back into the input cavity to make an electronic oscillator to generate radio waves. The gain of klystrons can be high, 60 dB (one million) or more, with output power up to tens of megawatts, but the bandwidth is narrow, usually a few percent although it can be up to 10% in some devices.[2]

how many species of daddy long legs are there?

More than 6,000 species

Ctenophores (comb jelly)

Most ctenophores that live near the surface are mostly colorless and almost transparent. However some deeper-living species are strongly pigmented, for example the species known as "Tortugas red"[51] (see illustration here), which has not yet been formally described.[15] Platyctenids generally live attached to other sea-bottom organisms, and often have similar colors to these host organisms.[15] The gut of the deep-sea genus Bathocyroe is red, which hides the bioluminescence of copepods it has swallowed.[41] The comb rows of most planktonic ctenophores produce a rainbow effect, which is not caused by bioluminescence but by the scattering of light as the combs move.[15][52] Most species are also bioluminescent, but the light is usually blue or green and can only be seen in darkness.[15] However some significant groups, including all known platyctenids and the cydippid genus Pleurobrachia, are incapable of bioluminescence.[53]

mudskippers

Mudskippers which can be found in the mudflats of mangrove forests from West Africa to New Guinea our fish that spend most of their time out of the water. A fish with feet.

Neutral Buoyancy Laboratory

NASA lab where they have a complete ISS mockup underwater. Astronauts put on counter weights and other buoyancy devices to mimic microgravity. They can also get a feel for how the ISS operates and where each hand hold and foot hold is and they can visibly see the layout within the structure prior to going into orbit. The NBL's main feature is a large indoor pool of water,[3] in which astronauts may perform simulated EVA tasks in preparation for upcoming missions. Trainees wear suits designed to provide neutral buoyancy to simulate the microgravity that astronauts would experience during spaceflight. During training exercises, neutral-buoyancy diving is used to simulate the weightlessness of space travel. To achieve this effect, suited astronauts or pieces of equipment are lowered into the pool using an overhead crane and then weighted in the water by support divers so that they experience minimal buoyant force and minimal rotational moment about their center of mass.[2] The suits worn by trainees in the NBL are down-rated from fully flight-rated EMU suits like those in use on the Space Shuttle and International Space Station. Divers breathe nitrox while working in the tank.

slender snipe eel

Nemichthys is a genus of eels in the snipe-eel family Nemichthyidae. It currently contains the following species: Nemichthys curvirostris (Strömman, 1896) (Boxer snipe-eel) Nemichthys larseni J. G. Nielsen & D. G. Smith, 1978 Nemichthys scolopaceus J. Richardson, 1848 (Slender snipe-eel)

H.266

New video format 'halves data use of 4K and 8K TVs' It could also pave the way for on-demand services to offer 8K content. The H.265 codec itself halved the bitrate requirement of its predecessor H.264, which is still widely in use. "H.265 requires about 10 gigabytes of data to transmit a 90-minute ultra-high definition [4K] video," explains a press release. "With this new technology, only 5GB are required to achieve the same quality." In order to stream 8K video reliably, tests have indicated that homes would require internet connections capable of more than 85 megabits per second (Mbps), which is beyond what many properties have today. However, that has the potential to drop to a more manageable 40-50Mbps if H.266 takes off. This would revolutionize VR.

Human virome

The human virome is the total collection of viruses in and on the human body. Viruses in the human body may infect both human cells and other microbes such as bacteria (as with bacteriophages). Viruses evolve rapidly and hence the human virome changes constantly. Every human being has a unique virome with a unique balance of species. The human virome is far from being completely explored and new viruses are discovered frequently. Unlike the roughly 40 trillion bacteria in a typical human microbiome, an estimate of the number of viral particles in a healthy adult human is not yet available, although virions generally outnumber individual bacteria 10:1 in nature.

Nitrox

Nitrox refers to any gas mixture composed (excepting trace gases) of nitrogen and oxygen. This includes atmospheric air, which is approximately 78% nitrogen, 21% oxygen, and 1% other gases, primarily argon. In the usual application, underwater diving, nitrox is normally distinguished from air and handled differently.[3] The most common use of nitrox mixtures containing oxygen in higher proportions than atmospheric air is in scuba diving, where the reduced partial pressure of nitrogen is advantageous in reducing nitrogen uptake in the body's tissues, thereby extending the practicable underwater dive time by reducing the decompression requirement, or reducing the risk of decompression sickness (also known as the bends).

Nuclear Magnetic Resonance (NMR)

Nuclear magnetic resonance (NMR) is a method of physical observation in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field (in the near field and therefore not involving electromagnetic waves) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved. Nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics, crystals as well as non-crystalline materials. NMR is also routinely used in advanced medical imaging techniques, such as in magnetic resonance imaging (MRI). All isotopes that contain an odd number of protons and/or neutrons (see Isotope) have an intrinsic nuclear magnetic moment and angular momentum, in other words a nonzero nuclear spin, while all nuclides with even numbers of both have a total spin of zero. The most commonly used nuclei are 1H and 13C, although isotopes of many other elements can be studied by high-field NMR spectroscopy as well.

What is an optocoupler and how does it work?

Optocoupler is a device that 'couples' two different electric circuits using light. Its basically used when you need to turn on a load in another circuit without loading the original/actuating signal. It is used widely in power electronics where the drive circuit should be loaded the least. It contains a light source typically IR and a photosensitive semiconductor which senses the IR. So, whenever the light shines on the material, a base current is generated with turns ON/OFF the device.

seeds that survive fire

Perhaps the most amazing fire adaptation is that some species actually require fire for their seeds to sprout. Some plants, such as the lodgepole pine, Eucalyptus, and Banksia, have serotinous cones or fruits that are completely sealed with resin. These cones/fruits can only open to release their seeds after the heat of a fire has physically melted the resin. Other species, including a number of shrubs and annual plants, require the chemical signals from smoke and charred plant matter to break seed dormancy. Some of these plants will only sprout in the presence of such chemicals and can remain buried in the soil seed bank for decades until a wildfire awakens them. Some plants are able to survive wildfires due to a clever layer of thermal insulation provided by their bark, dead leaves, or moist tissues. Certain trees, including larches and giant sequoias, have incredibly thick, fire retardant bark and can be directly burned without sustaining damage to their vital tissues (though they will eventually succumb to intense fires). Other plants, such as the Australian grass tree and South African aloes (pictured) retain dense, dead leaves around their stems to serve as insulation against the heat of a wildfire. Additionally, some plants have moist tissues that provide both thermal insulation and protect against dehydration during a fire. This strategy is common in a number of Protea species which have corky tissues to protect their buds from desiccation.

Spiders Ingest Nanotubes, Then Weave Silk Reinforced with Carbon

Spiders sprayed with water containing carbon nanotubes and graphene flakes have produced the toughest fibers ever measured, say materials scientists. MIT has thought of everything.. The team then used a neat trick to introduce carbon nanotubes and graphene flakes into the spider silk. They simply sprayed the spiders with water containing the nanotubes or flakes and then measured the mechanical properties of the silk that the spiders produced. For each strand of silk, they fixed the fiber between two C-shaped cardboard holders and placed it in a device that can measure the load on a fiber with a resolution of 15 nano-newtons and any fiber displacement with a resolution of 0.1 nanometers. The results make for impressive reading. "We measure a fracture strength up to 5.4 GPa, a Young's modulus up to 47.8 GPa and a toughness modulus up to 2.1 GPa," say Pugno and co. "This is the highest toughness modulus for a fibre, surpassing synthetic polymeric high performance fibres (e.g. Kelvar49) and even the current toughest knotted fibers," they say. In other words, giving spiders water that is infused with carbon nanotubes makes them weave silk stronger than any known fiber. The work raises some interesting questions. For a start, exactly how the spiders incorporate carbon nanotubes and graphene flakes into their silk is not clear. The team use spectroscopic methods to show that the carbon-based materials are present in the fiber but are unable to show exactly how.

Sea spider

Sea spiders, also called Pantopoda or pycnogonids, are marine arthropods of class Pycnogonida. They are cosmopolitan, found in oceans around the world. There are over 1300 known species, with legs ranging from 1 mm to over 70 cm. Although "sea spiders" are not true spiders, or even arachnids, their traditional classification as chelicerates would place them closer to true spiders than to other well-known arthropod groups, such as insects or crustaceans. This is in dispute, however, as genetic evidence suggests they may be the sister group to all other living arthropods.

how redshift can tell velocity?

So to determine an object's distance, we only need to know its velocity. Velocity is measurable thanks to the Doppler shift. By taking the spectrum of a distant object, such as a galaxy, astronomers can see a shift in the lines of its spectrum and from this shift determine its velocity.

cosmic ray vs solar wind

Some of the most violent phenomena in nature are thought to be responsible for cosmic rays, like hypernovae and black hole or neutron star collisions. Solar wind, on the other hand, is propelled by the Sun's surface radiation pressure, a timid force by comparison.

Infrasound

Sound waves with frequencies below 20 Hz. Infrasound, sometimes referred to as low-frequency sound, describes sound waves with a frequency below the lower limit of audibility (generally 20 Hz). Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high.

Spider mite

Spider mites are members of the Acari (mite) family Tetranychidae, which includes about 1,200 species. They generally live on the undersides of leaves of plants, where they may spin protective silk webs, and they can cause damage by puncturing the plant cells to feed. Spider mites are known to feed on several hundred species of plants. Hot, dry conditions are often associated with population build-up of spider mites. Under optimal conditions (approximately 27 °C), the two-spotted spider mite can hatch in as little as 3 days, and become sexually mature in as little as 5 days. One female can lay up to 20 eggs per day and can live for 2 to 4 weeks, laying hundreds of eggs. This accelerated reproductive rate allows spider mite populations to adapt quickly to resist pesticides, so chemical control methods can become somewhat ineffectual when the same pesticide is used over a prolonged period.[3]

spider eyes

Spiders usually have eight eyes (some have six or fewer), but few have good eyesight. They rely instead on touch, vibration and taste stimuli to navigate and find their prey. Most are able to detect little more than light-dark intensity changes which stimulate nocturnal web building, hunting or wandering activities and rapid movement to allow quick reactions against daytime predators (e.g. by dropping from webs). Some spiders have median eyes that can detect polarised light and they use this ability to navigate while hunting. https://bit.ly/3flGPMM

Tarrare

Tarrare (c. 1772 - 1798), sometimes spelled Tarare, was a French showman and soldier, noted for his unusual appetite and eating habits. Able to eat vast amounts of meat, he was constantly hungry; his parents could not provide for him, and he was turned out of the family home as a teenager. He travelled France in the company of a band of thieves and prostitutes, before becoming the warm-up act to a travelling charlatan. In this act he would swallow corks, stones, live animals and a whole basketful of apples. He then took this act to Paris where he worked as a street performer. At the start of the War of the First Coalition, Tarrare joined the French Revolutionary Army, where even quadruple the standard military ration was unable to satisfy his large appetite. He would eat any available food from gutters and refuse heaps but his condition still deteriorated through hunger. He was hospitalised due to exhaustion and became the subject of a series of medical experiments to test his eating capacity, in which, among other things, he ate a meal intended for 15 people in a single sitting, ate live cats, snakes, lizards and puppies, and swallowed eels whole without chewing. Despite his unusual diet, he was underweight, and with the exception of his eating habits he showed no signs of mental illness other than what was described as an apathetic temperament. General Alexandre de Beauharnais decided to put Tarrare's abilities to military use, and employed him as a courier for the French army, with the intention that he would swallow documents, pass through enemy lines, and recover them from his stool once safely at his destination. Tarrare could not speak German, and on his first mission was captured by Prussian forces, severely beaten, and underwent a mock execution before being returned to French lines. Chastened by this experience, he agreed to submit to any procedure that might cure his appetite, and was treated with laudanum, tobacco pills, wine vinegar and soft-boiled eggs. The procedures failed, and doctors could not keep him on a controlled diet; he would sneak out of the hospital to scavenge for offal in gutters, rubbish heaps and outside butchers' shops, and attempted to drink the blood of other patients in the hospital and to eat the corpses in the hospital morgue. After being suspected of eating a toddler he was ejected from the hospital. He reappeared four years later in Versailles with a case of severe tuberculosis, and died shortly afterwards, following a lengthy bout of exudative diarrhoea.

Terpene

Terpenes are a large and diverse class of organic compounds, produced by a variety of plants, particularly conifers, and by some insects. They often have a strong odor and may protect the plants that produce them by deterring herbivores and by attracting predators and parasites of herbivores.

Africanized bee

The Africanized bee, also known as the Africanized honey bee and known colloquially as the "killer bee", is a hybrid of the western honey bee (Apis mellifera), produced originally by crossbreeding of the East African lowland honey bee (A. m. scutellata) with various European honey bee subspecies such as the Italian honey bee (A. m. ligustica) and the Iberian honey bee (A. m. iberiensis). The East African lowland honey bee was first introduced to Brazil in 1956 in an effort to increase honey production, but 26 swarms escaped quarantine in 1957. Since then, the hybrid has spread throughout South America and arrived in North America in 1985. Hives were found in south Texas in the United States in 1990. Africanized honey bees are typically much more defensive than other varieties of honey bees, and react to disturbances faster than European honey bees. They can chase a person a quarter of a mile (400 m); they have killed some 1,000 humans, with victims receiving 10 times more stings than from European honey bees.[1] They have also killed horses and other animals. There are 29 recognized subspecies of Apis mellifera based largely on geographic variations. All subspecies are cross-fertile. Geographic isolation led to numerous local adaptations.

Arab Spring

The Arab Spring was a series of anti-government protests, uprisings, and armed rebellions that spread across much of the Arab world in the early 2010s. It began in response to oppressive regimes and a low standard of living, starting with protests in Tunisia. From Tunisia, the protests then spread to five other countries: Libya, Egypt, Yemen, Syria and Bahrain, where either the ruler was deposed (Zine El Abidine Ben Ali, Muammar Gaddafi, Hosni Mubarak, and Ali Abdullah Saleh) or major uprisings and social violence occurred, including riots, civil wars or insurgencies. The importance of external factors versus internal factors to the protests' spread and success is contested.[5] Social media is one way governments try to inhibit protests. In many countries, governments shut down certain sites or blocked Internet service entirely, especially in the times preceding a major rally

Brazilian wandering spiders

The Brazilian wandering spider (a ctenid spider) is a large brown spider similar to North American wolf spiders in appearance, although somewhat larger. It has a highly toxic venom and is regarded (along with the Australian funnel-web spiders) as among the most dangerous spiders in the world.[3] Based on one of the few pharmacological studies performed in the 1970s, Phoneutria's venom toxicity was more virulent than both Atrax and Latrodectus. As their name suggests, Brazilian wandering spiders are active ground hunters. If the spider has a reason to be alarmed, it will bite in order to protect itself, but unless startled or provoked, most bites will be without venom. Venom bites will occur if the spider is pressed against something and hurt. In this case, the high levels of serotonin contained in the venom, plus at minimum-strong chelicera, will contribute to deliver a very painful bite. Children are more sensitive to the venom of wandering spiders. The spiders often make threatening gestures, such as raising up their legs, or hopping sideways on the ground, which might amuse a child to the point of reaching towards the spider. In male humans, bites of this spider may also result in prolonged painful penile erections (priapism). Scientists are attempting to create an erectile dysfunction treatment that can be combined with other medicines out of the peptide that causes this reaction.

Doomsday Clock

The Doomsday Clock is a symbol that represents the likelihood of a man-made global catastrophe. Maintained since 1947 by the members of the Bulletin of the Atomic Scientists,[1] the Clock is a metaphor for threats to humanity from unchecked scientific and technical advances. The Clock represents the hypothetical global catastrophe as "midnight" and the Bulletin's opinion on how close the world is to a global catastrophe as a number of "minutes" to midnight, assessed in January of each year. The main factors influencing the Clock are nuclear risk and global warming (climate change).[2] The Bulletin's Science and Security Board also monitors new developments in the life sciences and technology that could inflict irrevocable harm to humanity. The clock was set at two minutes to midnight in January 2018, and left unchanged in 2019 due to the twin threats of nuclear weapons and the increasing effects of global warming.[4] On January 23, 2020, it was moved forward to 100 seconds (1 minute 40 seconds) before midnight, based on the increased threats to global stability posed by "a nuclear blunder", exacerbated by the rate of climate change.

Great Molasses Flood

The Great Molasses Flood, also known as the Boston Molasses Disaster occurred on January 15, 1919, in the North End neighborhood of Boston, Massachusetts. A large storage tank filled with 2.3 million US gal (8,700 m^3) weighing approximately 13,000 short tons (12,000 t) of molasses burst, and the resultant wave of molasses rushed through the streets at an estimated 35 mph (56 km/h), killing 21 and injuring 150.[4] The event entered local folklore and residents claimed for decades afterwards that the area still smelled of molasses on hot summer days. On January 15, 1919, the temperature had risen above 40 °F (4 °C), climbing rapidly from the frigid temperatures of the preceding days,[6]:91, 95 and the previous day a ship had delivered a fresh load of molasses, which was warmed to reduce its viscosity for transfer.[7] Possibly due to the thermal expansion of the older cold molasses inside, the tank burst open and collapsed at approximately 12:30 pm. Witnesses reported that they felt the ground shake and heard a roar as it collapsed, a long rumble similar to the passing of an elevated train; others reported a tremendous crashing, a deep growling, "a thunderclap-like bang!", and a machine gun-like sound as the rivets shot out of the tank.

Hubble Deep Field

The Hubble Deep Field (HDF) is an image of a small region in the constellation Ursa Major, constructed from a series of observations by the Hubble Space Telescope. It covers an area about 2.6 arcminutes on a side, about one 24-millionth of the whole sky, which is equivalent in angular size to a tennis ball at a distance of 100 metres.[1] The image was assembled from 342 separate exposures taken with the Space Telescope's Wide Field and Planetary Camera 2 over ten consecutive days between December 18 and 28, 1995.

Plateau-Rayleigh instability

The Plateau-Rayleigh instability, often just called the Rayleigh instability, explains why and how a falling stream of fluid breaks up into smaller packets with the same volume but less surface area. It is related to the Rayleigh-Taylor instability and is part of a greater branch of fluid dynamics concerned with fluid thread breakup. This fluid instability is exploited in the design of a particular type of ink jet technology whereby a jet of liquid is perturbed into a steady stream of droplets. The driving force of the Plateau-Rayleigh instability is that liquids, by virtue of their surface tensions, tend to minimize their surface area. A considerable amount of work has been done recently on the final pinching profile by attacking it with self-similar solutions.

South Pole Wall

The South Pole Wall (SPW or The South Pole Wall) is a massive cosmic structure formed by a giant wall of galaxies (a galaxy filament) that extends across at least 700 million light-years of space. The structure is coincident with the celestial South Pole and is, according to the international team of astronomers that discovered the South Pole Wall, "...the largest contiguous feature in the local volume and comparable to the Sloan Great Wall at half the distance ...".[1] Its discovery was announced by Daniel Pomarède of Paris-Saclay University and R. Brent Tully and colleagues of the University of Hawaii in July 2020. Pomarede explained, "One might wonder how such a large and not-so distant structure remained unnoticed. This is due to its location in a region of the sky that has not been completely surveyed, and where direct observations are hindered by foreground patches of galactic dust and clouds. We have found it thanks to its gravitational influence, imprinted in the velocities of a sample of galaxies."[3]

World Magnetic Model

The World Magnetic Model (WMM) is a large spatial-scale representation of the Earth's magnetic field. It was developed jointly by the US National Geophysical Data Center and the British Geological Survey. The data and updates are issued by the US National Geospatial Intelligence Agency and the UK Defence Geographic Centre. Updated model coefficients are released at 5-year intervals, with WMM2015 (released Dec 15, 2014) supposed to last until December 31, 2019. However, due to extraordinarily large and erratic movements of the north magnetic pole, an out-of-cycle update (WMM2015v2) was released in February 2019[3] (delayed by a few weeks due to the U.S. federal government shutdown)[4] to accurately model the magnetic field above 55° north latitude until the end of 2019. The next regular update (WMM2020) occurred in December 2019.[5]

Zeeman effect

The Zeeman effect, named after the Dutch physicist Pieter Zeeman, is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules. Since the distance between the Zeeman sub-levels is a function of magnetic field strength, this effect can be used to measure magnetic field strength, e.g. that of the Sun and other stars or in laboratory plasmas. The Zeeman effect is very important in applications such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance imaging (MRI) and Mössbauer spectroscopy. It may also be utilized to improve accuracy in atomic absorption spectroscopy. A theory about the magnetic sense of birds assumes that a protein in the retina is changed due to the Zeeman effect.

inflation field

The inflaton field is a hypothetical scalar field that is theorized to drive cosmic inflation in the very early universe. In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the early universe. The inflationary epoch lasted from 10^−36 seconds after the conjectured Big Bang singularity to some time between 10^−33 and 10^−32 seconds after the singularity. Following the inflationary period, the universe continued to expand, but at a slower rate. The acceleration of this expansion due to dark energy began after the universe was already over 9 billion years old (~4 billion years ago).

Interplanetary medium

The interplanetary medium (IPM) is the material which fills the Solar System, and through which all the larger Solar System bodies, such as planets, dwarf planets, asteroids, and comets, move. The interplanetary medium includes interplanetary dust, cosmic rays, and hot plasma from the solar wind.

parapsychology

the study of mental phenomena which are excluded from or inexplicable by orthodox scientific psychology (such as hypnosis, telepathy, etc.).

linger

to be slow in leaving or going away stay in a place longer than necessary because of a reluctance to leave.

bushmeat

wild animals being hunted by local people, frequently illegally, for food or to supply restaurants.

Ommatidium

The compound eyes of arthropods like insects, crustaceans and millipedes are composed of units called ommatidia (singular: ommatidium). An ommatidium contains a cluster of photoreceptor cells surrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea. Each ommatidium is innervated by one axon bundle (usually consisting of 6-9 axons, depending on the number of rhabdomeres) and provides the brain with one picture element. The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of arthropod and range from as low as 5 as in the Antarctic isopod Glyptonotus antarcticus, or a handful in the primitive Zygentoma, to around 30,000 in larger Anisoptera dragonflies and some Sphingidae moths.

Gizzard

The gizzard is an organ found in the digestive tract of some animals, including archosaurs (pterosaurs, crocodiles, alligators, dinosaurs including birds), earthworms, some gastropods, some fish, and some crustaceans. This specialized stomach constructed of thick muscular walls is used for grinding up food, often aided by particles of stone or grit. In certain insects and molluscs, the gizzard features chitinous plates or teeth. Birds swallow food and store it in their crop if necessary. Then the food passes into their glandular stomach, also called the proventriculus, which is also sometimes referred to as the true stomach. This is the secretory part of the stomach. Then the food passes into the gizzard (also known as the muscular stomach or ventriculus). The gizzard can grind the food with previously swallowed stones and pass it back to the true stomach, and vice versa. In layman's terms, the gizzard 'chews' the food for the bird as it does not have teeth to chew food the way humans and other mammals do. Bird gizzards are lined with a tough layer made of the carbohydrate-protein complex koilin, to protect the muscles in the gizzard. By comparison, while in birds the stomach occurs in the digestive tract prior to the gizzard, in grasshoppers the gizzard occurs prior to the stomach, while in earthworms there is only a gizzard, and no stomach. Some animals that lack teeth will swallow stones or grit to aid in fragmenting hard foods. All birds have gizzards, but not all will swallow stones or grit. Those that do employ the following method of chewing: A bird swallows small bits of gravel that act as 'teeth' in the gizzard, breaking down hard food such as seeds and thus helping digestion. These stones are called gizzard stones or gastroliths and usually become round and smooth from the polishing action in the animal's stomach. When too smooth to do their required work, they may be excreted or regurgitated.

Heliosheath

The heliosheath is the region of the heliosphere beyond the termination shock. Here the wind is slowed, compressed and made turbulent by its interaction with the interstellar medium. At its closest point, the inner edge of the heliosheath lies approximately 80 to 100 AU from the Sun. A proposed model hypothesizes that the heliosheath is shaped like the coma of a comet, and trails several times that distance in the direction opposite to the Sun's path through space. At its windward side, its thickness is estimated to be between 10 and 100 AU.[39] Voyager project scientists have determined that the heliosheath is not "smooth" - it is rather a "foamy zone" filled with magnetic bubbles, each about 1 AU wide. These magnetic bubbles are created by the impact of the solar wind and the interstellar medium.[40][41] Voyager 1 and Voyager 2 began detecting evidence for the bubbles in 2007 and 2008, respectively. The probably sausage-shaped bubbles are formed by magnetic reconnection between oppositely oriented sectors of the solar magnetic field as the solar wind slows down. They probably represent self-contained structures that have detached from the interplanetary magnetic field.

mosquito life cycle

The mosquito goes through four separate and distinct stages of its life cycle: Egg, Larva, Pupa, and Adult. Egg: Eggs are laid one at a time or attached together to form "rafts." They float on the surface of the water. In the case of Culex and Culiseta species, the eggs are stuck together in rafts of up to 200. Anopheles, Ochlerotatus, and Aedes, as well as many other genera, do not make egg rafts, but lay their eggs singly. Culex, Culiseta, and Anopheles lay their eggs on the water surface while many Aedes and Ochlerotatus lay their eggs on damp soil that will be flooded by water. Most eggs hatch into larvae within 48 hours; others might withstand subzero winters before hatching. Water is a necessary part of their habitat. Larva: The larva (plural - larvae) lives in the water and comes to the surface to breathe. Larvae shed (molt) their skins four times, growing larger after each molt. Most larvae have siphon tubes for breathing and hang upside down from the water surface. Anopheles larvae do not have a siphon and lie parallel to the water surface to get a supply of oxygen through a breathing opening. Coquillettidia and Mansonia larvae attach to plants to obtain their air supply. The larvae feed on microorganisms and organic matter in the water. During the fourth molt the larva changes into a pupa. Pupa: The pupal stage is a resting, non-feeding stage of development, but pupae are mobile, responding to light changes and moving (tumble) with a flip of their tails towards the bottom or protective areas. This is the time the mosquito changes into an adult. This process is similar to the metamorphosis seen in butterflies when the butterfly develops - while in the cocoon stage - from a caterpillar into an adult butterfly. In Culex species in the southern United States this takes about two days in the summer. When development is complete, the pupal skin splits and the adult mosquito (imago) emerges. Adult: The newly emerged adult rests on the surface of the water for a short time to allow itself to dry and all its body parts to harden. The wings have to spread out and dry properly before it can fly. Blood feeding and mating does not occur for a couple of days after the adults emerge. How long each stage lasts depends on both temperature and species characteristics. For instance, Culex tarsalis, a common California (USA) mosquito, might go through its life cycle in 14 days at 70° F and take only 10 days at 80° F. On the other hand, some species have naturally adapted to go through their entire life cycle in as little as four days or as long as one month.

Is the opossum a marsupial?

The most notable is the Virginia opossum or common opossum—the only marsupial (pouched mammal) found in the United States and Canada. A female opossum gives birth to helpless young as tiny as honeybees. Babies immediately crawl into the mother's pouch, where they continue to develop.

Hubble's law

The observation in physical cosmology that galaxies are moving away from the Earth at velocities proportional to their distance.

Coulter pines

The outstanding characteristic of this tree is the large, spiny cones which are 20-40 cm (7.9-15.7 in) long, and weigh 2-5 kg (4.4-11.0 lb) when fresh. Coulter pines produce the largest cones of any pine tree species (people are actually advised to wear hardhats when working in Coulter pine groves), although the slender cones of the sugar pine are longer. The large size of the cones has earned them the nickname "widowmakers" among locals.

Sorption

The physical or chemical linkage of substances, either by absorption or by adsorption. Sorption is a physical and chemical process by which one substance becomes attached to another.

Termination shock

The termination shock is the point in the heliosphere where the solar wind slows down to subsonic speed (relative to the Sun) because of interactions with the local interstellar medium. This causes compression, heating, and a change in the magnetic field. In the Solar System, the termination shock is believed to be 75 to 90 astronomical units[30] from the Sun. In 2004, Voyager 1 crossed the Sun's termination shock, followed by Voyager 2 in 2007. The shock arises because solar wind particles are emitted from the Sun at about 400 km/s, while the speed of sound (in the interstellar medium) is about 100 km/s. (The exact speed depends on the density, which fluctuates considerably. For comparison, the Earth orbits the Sun at about 30 km/s, the ISS orbits the Earth at about 7.7 km/s, airliners fly over the ground at about 0.2-0.3 km/s, a car on a typical limited-access highway achieves about 0.03 km/s, and of course humans walk around 0.001 km/s.) The interstellar medium, although very low in density, nonetheless has a relatively constant pressure associated with it; the pressure from the solar wind decreases with the square of the distance from the Sun. As one moves far enough away from the Sun, the pressure of the solar wind drops to where it can no longer maintain supersonic flow against the pressure of the interstellar medium, at which point the solar wind slows to below its speed of sound, causing a shock wave. Further from the Sun, the termination shock is followed by the heliopause, where the two pressures become equal and solar wind particles are stopped by the interstellar medium. At a distance of more than a few solar radii from the Sun, the solar wind reaches speeds of 250 to 750 kilometers per second and is supersonic,[4] meaning it moves faster than the speed of the fast magnetosonic wave. The flow of the solar wind is no longer supersonic at the termination shock. The Voyager 2 spacecraft crossed the shock more than five times between 30 August and 10 December 2007.[5] Voyager 2 crossed the shock about a billion kilometers closer to the Sun than the 13.5-billion-kilometer distance where Voyager 1 came upon the termination shock.[6][7] The spacecraft moved outward through the termination shock into the heliosheath and onward toward the interstellar medium. Other related phenomena include the aurora (northern and southern lights), the plasma tails of comets that always point away from the Sun, and geomagnetic storms that can change the direction of magnetic field lines.

There's a strong correlation between Coltan mining, violence in Eastern DRC, and major tech supply chain.

There was a spike in violence in Eastern DRC in the lead up to the release of the PlayStation 2 for example, as the PS2 used an inordinate amount of Coltan on its board (thus increasing demand and price suppliers were willing to pay for it). As for why the PS2 was so Coltan heavy, it's because it was extremely power-inefficient. The jump from PS1 to PS2 graphics was much more significant than the jump from PS2 to PS3, however the PS3 had a more modern chip architecture, that could use power more efficiently and effectively. In order to draw the amount of power the console needed without frying the board, the first gen PS2 was essentially covered in little Coltan resistors that could manage the chip's power demands without causing the whole thing to explode. Coltan (short for columbite-tantalites and known industrially as tantalite) is a dull black metallic ore from which are extracted the elements niobium and tantalum. The niobium-dominant mineral in coltan is columbite (after niobium's original American name columbium), and the tantalum-dominant mineral is the tantalite. Tantalum from coltan is used to manufacture tantalum capacitors which are used for mobile phones, personal computers, automotive electronics, and cameras.[2] Coltan mining[3][4] has financed serious conflict in the Democratic Republic of Congo, including the Ituri conflict and the Second Congo War.

Thousands of PCs break exaFLOP barrier

There's a race to deploy the first supercomputer in the U.S. to break the exaFLOP barrier. Intel says it will be first with Aurora in 2021, while AMD and Cray claim they will be first with Frontier. Either way, the Department of Energy will win, because both computers will be deployed at DOE facilities. An exaFLOP is one quintillion (10^18) floating-point operations per second, or 1,000 petaFLOPS. To match what a one exaFLOP computer system can do in just one second, you'd have to perform one calculation every second for 31,688,765,000 years. While the supercomputing stalwarts continue to build their systems, Folding@Home just crossed the exaFLOP barrier ahead of IBM, Intel, Nvidia, and the Department of Energy. Folding@home is a distributed computing project running for 20 years. It was administered first by the chemistry department at Stanford University and as of last year, by Washington University in St. Louis. Its software runs on individual PCs and remains idle as long as the computer is in use, then it kicks in when the PC is idle. The project simulates how proteins misfold and cause diseases such as cancer and Alzheimer's Disease.

Spider Uses Web As Slingshot To Ensnare Prey

This high-velocity maneuver is a nightmare if you're a fly. There's a type of spider that can slowly stretch its web taut and then release it, causing the web to catapult forward and ensnare unsuspecting prey in its strands. Triangle-weaver spiders use their own web the way humans might use a slingshot or a crossbow. Scientists from the University of Akron say this is a process called "power amplification." The web is stretchy, which allows the spider to amplify its own power by using what the scientists call "elastic recoil."

How does tooth decay occur, and how does fluoride help?

Tooth decay occurs due to growth of the microbes (Streptococcus mutans[1] and Lactobacillus sp.) Fluorine is a halogen and shows antimicrobial activity. It kills the bacteria and destroys the biofilms growing on the surface of the teeth. Tooth enamel is mainly made up of hydroxyapatite, a hard-wearing mineral that contains a matrix of positive calcium ions and negative phosphate ions. When the enamel of your teeth comes into contact with acid - including your saliva - the calcium gets stripped away, dissolving the tooth[2]. Thus, teeth structure is easily damaged due to acids released by the bacteria. Fluorine reacts with the hydroxyapatite and replaces the hydrogen and forms fluorapatite which is stronger and more resistant to the acid reactions of bacteria.

Twistronics

Twistronics (from twist and electronics) is the study of how the angle (the twist) between layers of two-dimensional materials can change their electrical properties.[1][2] Materials such as bilayer graphene have been shown to have vastly different electronic behavior, ranging from non-conductive to superconductive, that depends sensitively on the angle between the layers.[3][4] The term was first introduced by the research group of Efthimios Kaxiras at Harvard University in their theoretical treatment of graphene superlattices.

Ultra-high vacuum

Ultra-high vacuum (UHV) is the vacuum regime characterised by pressures lower than about 100 nanopascal. 1 micron mercury = 133 million nanopascals Measurement of high vacuum is done using a non-absolute gauge that measures a pressure-related property of the vacuum, for example, its thermal conductivity. See, for example, Pacey.[2] These gauges must be calibrated.[3] The gauges capable of measuring the lowest pressures are magnetic gauges based upon the pressure dependence of the current in a spontaneous gas discharge in intersecting electric and magnetic fields.[4]

Venom

Venom is a secretion containing one or more toxins produced by an animal. Venoms kill through the action of at least four major classes of toxin, namely necrotoxins and cytotoxins, which kill cells; neurotoxins, which affect nervous systems; and myotoxins, which damage muscles. Biologically, venom is distinguished from poison in that poisons are ingested, while venom is delivered in a bite, sting, or similar action. Myotoxins, which damage muscles by binding to a receptor, are small, basic peptides found in snake (such as rattlesnake) and lizard venoms. Neurotoxins, which primarily affect the nervous systems of animals.[5] These include ion channel toxins that disrupt ion channel conductance. Black widow spider, scorpion, box jellyfish, cone snail, centipede and blue-ringed octopus venoms (among many others) function in this way. Cytotoxins, which kill individual cells, are found in the apitoxin of honey bees and the venom of black widow spiders.

Spider silk

When spiders moved from the water to the land in the Early Devonian period, they started making silk to protect their bodies and their eggs.[3][5] Spiders gradually started using silk for hunting purposes, first as guide lines and signal lines, then as ground or bush webs, and eventually as the aerial webs that are familiar today. Spiders produce silk from their spinneret glands located at the tip of their abdomen. Each gland produces a thread for a special purpose - for example a trailed safety line, sticky silk for trapping prey or fine silk for wrapping it. Spiders use different gland types to produce different silks, and some spiders are capable of producing up to eight different silks during their lifetime. Most spiders have three pairs of spinnerets, each having its own function - there are also spiders with just one pair and others with as many as four pairs. Webs allow a spider to catch prey without having to expend energy by running it down. Thus it is an efficient method of gathering food. However, constructing the web is in itself an energetically costly process because of the large amount of protein required, in the form of silk. In addition, after a time the silk will lose its stickiness and thus become inefficient at capturing prey. It is common for spiders to eat their own web daily to recoup some of the energy used in spinning. The silk proteins are thus recycled. The tensile strength of spider silk is greater than the same weight of steel and has much greater elasticity. Its microstructure is under investigation for potential applications in industry, including bullet-proof vests and artificial tendons. Researchers have used genetically modified mammals to produce the proteins needed to make this material.

Can quarks emit or interact with photons in any way?

Yes, quarks are electrically charged, thus they do interact with photons. You need a rather hard (high energy) photon to observe that, because quarks never live in isolation, they always appear in pairs, or larger groups. In order to interact with a single quark, the photon must be able to resolve individual quarks within such a group, and that means its wavelength should be of the order of (or shorter than) the typical distance between quarks in a hadron. Some examples of quarks interacting directly with photons are: - production of hadrons in high energy electon-positron annihilation (a quark-antiquark pair is created from a virtual photon), - neutral pion decay - a quark and an antiquark annihilate producing photons - photoproduction of hadrons - a high energy photon collides with a quark inside hadron, knocking it out and creating more hadrons.

scrub bull

a "scrub" (also known as a "scrubber", or "scrub bull") is a male cattle who escaped castration early on in life However, when you have thousands of cattle over hundreds of thousands of acres (the average station size in WA is one million acres), it is pretty hard to catch every single animal each year. So sometimes the young boy cattle don't get mustered, and of course that means they don't get castrated. If this happens for a few years in a row, they become somewhat of a "rebel" or "rogue"... aka a scrubber. They are cheeky boys who try and avoid being mustered by hiding out in the scrub, hence the name scrub bulls. The older a scrub bull gets though, the more rebellious he comes. They can put up quite a fight during muster, and once in the yards, they have been known to charge at the jackeroos and jillaroos.

Platitude

a commonplace, stale, or trite remark; stale; overused expression; a thought-terminating cliché Platitudes have been criticized as giving a false impression of wisdom, making it easy to accept falsehoods. A platitude is even worse than a cliché. It's a sanctimonious cliché, a statement that is not only old and overused but often moralistic and imperious. They therefore shape our view of the world, and can lull us into accepting things that are actually false and foolish.

Metamaterial

a man made material engineered to have a property that is not found in naturally occurring materials. For microwave radiation, the features are on the order of millimeters. Microwave frequency metamaterials are usually constructed as arrays of electrically conductive elements (such as loops of wire) that have suitable inductive and capacitive characteristics. Many microwave metamaterials use split-ring resonators. Photonic metamaterials are structured on the nanometer scale and manipulate light at optical frequencies. Photonic crystals and frequency-selective surfaces such as diffraction gratings, dielectric mirrors and optical coatings exhibit similarities to subwavelength structured metamaterials. However, these are usually considered distinct from metamaterials, as their function arises from diffraction or interference and thus cannot be approximated as a homogeneous material.

evergreen

a tree/plant that does not lose its leaves in the winter and stays green all year round

Bioinformatics

application of mathematics and computer science to store, retrieve, and analyze biological data Bioinformatics is an interdisciplinary field that develops methods and software tools for understanding biological data, in particular when the data sets are large and complex.

troglodyte

cave dweller a person who is regarded as being deliberately ignorant or old-fashioned. an animal that lives in a cave such as the Olm which is a blind cave dwelling salamander with external gills

epideictic

designed primarily for rhetorical display; display or show Epideictic oratory, also called ceremonial oratory, according to Aristotle, a type of suasive speech designed primarily for rhetorical effect. Epideictic oratory was panegyrical, declamatory, and demonstrative. Its aim was to condemn or to eulogize an individual, cause, occasion, movement, city, or state.

extirpation

destruction; extinction to remove or destroy totally; do away with; exterminate. to pull up by or as if by the roots; root up: to extirpate an unwanted hair.

Nebulizer

device that creates a mist used to deliver medication for giving respiratory treatment

prosaic

dull, lacking in distinction and originality; matter-of-fact, straightforward; characteristic of prose, not poetic having the style or diction of prose; lacking poetic beauty.

arachnophobia

fear of spiders

splotchy

marked or covered with spots

Prototaxites

massive tree-like fossils thought to be primitive fungi, 400 M years ago. Prototaxites formed large trunk-like structures up to 1 metre (3 ft) wide, reaching 8 metres (26 ft) in height,[1] made up of interwoven tubes around 50 micrometres (0.0020 in) in diameter, making it by far the largest land-dwelling organism of its time.

how many eel species are there

more than 800 species

unreasonable

not guided by or based on good sense absurd; foolish; illogical; irrational

galaxy vs quasar

quasars are young active galaxies meaning stars are forming and the supermassive black hole at the center is ea Most large galaxies, including our own Milky Way, have a supermassive black hole at their centre. Once the material runs out the active galaxy becomes a regular galaxy. The quasars which have been observed are billions of light years away. This means that they are young galaxies as seen in the early universe.

combinatorial

relating to the selection of a given number of elements from a larger number without regard to their arrangement. You can use combinatorics to calculate the "total number of possible outcomes". Here is an example: Four children, called A, B, C and D, sit randomly on four chairs.

morbidity

the condition of being diseased The noun morbidity means "the quality of being unhealthful." If you can't watch your sister's morbidity get any worse, you might sign her up with a nutritionist and a personal trainer.

leading edge

the forefront or vanguard, especially of technological development.

k-shell

the innermost shell of electrons surrounding an atomic nucleus and constituting the lowest available energy level for the electrons

Silent Generation

youth of the 50's that seemed to conform to middle class culture without question. The Silent Generation is the demographic cohort following the Greatest Generation and preceding the baby boomers. The generation is generally defined as people born from 1928 to 1945.[1] By this definition and U.S. Census data, there are currently 23 million Silents in the United States as of 2019. The Silent Generation were children of the Great Depression whose parents, having revelled in the highs of the Roaring Twenties, now faced great economic hardship and struggled to provide for their families. Before reaching their teens they shared with their parents the horrors of World War II but through children's eyes. Many lost their fathers or older siblings who were killed in the war. They saw the fall of Nazism and the catastrophic devastation capable of the nuclear bomb. When the Silent Generation began coming of age after World War II, they were faced with a devastated social order within which they would spend their early adulthood and a new enemy in Communism via the betrayal of post-war agreements and rise of the Soviet Union. Unlike the previous generation who had fought for "changing the system," the Silent Generation were about "working within the system." They did this by keeping their heads down and working hard, thus earning themselves the "silent" label. Their attitudes leaned toward not being risk-takers and playing it safe. Fortune magazine's story on the "College Class of '49" was subtitled "Taking No Chances."


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