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submitted 2 hours ago* (last edited 2 hours ago) by TankieTanuki@hexbear.net to c/science@hexbear.net

A spider sputter-coated in gold to prepare it as a specimen for scanning electron microscopy.

A conductive coating is needed to prevent charging of a specimen with an electron beam in conventional SEM mode (high vacuum, high voltage).

This item was on display at the Australian Museum in Sydney, New South Wales, Australia.

—Wikipedia

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submitted 21 hours ago* (last edited 21 hours ago) by hypercracker@hexbear.net to c/science@hexbear.net

Illustration from The Machinery of Life by David S. Goodsell

Molecules constantly diffuse within the interior of cells, randomly bumping from place to place. This illustration shows several snapshots from a computer simulation of a protein and a sugar molecule diffusing inside a bacterial cell. The path of the protein is shown in blue and the path of sugar is shown in red. They start at opposite ends and explore much of the space inside before they reach each other.

I really like this because it illustrates, more than anything else, that our biomolecules don't "want" to do anything, go some place, bind somewhere; it's just physics and unbelievable quantities of random interactions. Excerpt from the text:

One basic thing remains the same at our size and at molecular size: the solidity of matter. At the scale of molecules, we do not need to worry too much about the odd things that happen with quantum mechanics: to a first approximation, molecules have a definite size and shape, and it is perfectly fine to imagine them bumping into each other and fitting together if the shapes match. If we look closely, their edges may be a bit fuzzy, but for most purposes, we can think of them as physical objects like tables and chairs.

Other properties, however, are very different when we enter the molecular world. For instance, molecules are so small that gravity is completely negligible. The motions and the interactions of biological molecules are completely dominated by the surrounding water molecules. At room temperature, a medium-sized protein travels at a rate of about 5 m/s (the speed of a fast runner). If placed alone in space, this protein would travel its own length in about a nanosecond (a billionth of a second). Inside the cell, however, this protein is battered from all sides by water molecules. It bounces back and forth, always at great speed, but takes a long time to get anywhere. When surrounded by water, this typical protein now requires almost a thousand times longer to move a protein-sized distance.

Imagine a similar situation in our world. You enter an airline terminal and want to reach a ticket window on the far side of the room. The distance is several meters—a distance comparable to your own size. If the room is empty, you dash across in a matter of seconds. But imagine instead that the room is crowded full of other people trying to get to their respective windows. With all the pushing and shoving, it now takes you 15 minutes to cross the room! In this time, you may be pushed all over the room, perhaps even back to your starting point a few times. This is similar (although molecules do not have a goal in mind) to the contorted path molecules take in the cell.

You might ask how anything ever gets done in this chaotic world. It is true that the motion is random, but it is also true that the motion is very fast compared to the motion in our familiar world. Random, diffusive motion is fast enough to perform most of the tasks in the cell. Each molecule simply bumps around until it finds the right place.

To get an idea of how fast this motion is, imagine a typical bacterial cell and place an enzyme at one end and a sugar molecule at the other. They will bump around and wander through the whole cell, encountering many molecules along the way. On average, though, it will only take about a second for those two molecules to bump into each other at least once. This is truly remarkable: this means that any molecule in a typical bacterial cell, during its chaotic journey through the cell, will encounter almost every other molecule in a matter of seconds. So as you are looking at the illustrations in this book, remember that static images give only a single snapshot of this teeming molecular world.

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The beginning of the article

Who knew a dragon’s tongue could be so long?

Astronomers announced last week that they had discovered a black hole spitting energy across 23 million light-years of intergalactic space. Two jets, shooting in opposite directions, compose the biggest lightning bolt ever seen in the sky — about 140 times as long as our own Milky Way galaxy is wide, and more than 10 times the distance from Earth to Andromeda, the nearest large spiral galaxy.

Follow-up observations with optical telescopes traced the eruption to a galaxy 7.5 billion light-years away that existed when the universe was less than half its current age of 14 billion years. At the heart of that galaxy was a black hole spewing energy equivalent to the output of more than a trillion stars.

“The Milky Way would be a little dot in these two giant eruptions,” said Martijn Oei, a postdoctoral researcher at the California Institute of Technology. Dr. Oei led the team that made the discovery, which was reported in Nature on Sept. 18 and announced on the journal’s cover with an illustration reminiscent of a “Star Wars” poster. The astronomers have named the black hole Porphyrion, after a giant in Greek mythology — a son of Gaia — who fought the gods and lost.

The discovery raises new questions of how such black holes could affect the evolution and structure of the universe.

Wikipedia: Porphyrion (radio galaxy)

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The Immune System Piercing a Bacterial Cell Wall

Our blood contains proteins that recognize and destroy invading cells and viruses. This illustration shows a cross section through a bacterial cell wall (lower half, in greens, blues and purples) being attacked by proteins in the blood serum (at the top, in yellows and oranges). Y-shaped antibodies begin the process by binding to the surface of the cell, and are in turn recognized by the six-armed protein at upper center. This begins a cascade of actions that ultimately lead to the formation of a membrane attack complex, shown here piercing the cell wall of the bacterium (1,000,000 X).

Source

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submitted 3 days ago* (last edited 3 days ago) by Dirt_Owl@hexbear.net to c/science@hexbear.net

thanks for showing me this @ElChapoDeChapo@hexbear.net

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submitted 1 week ago by git@hexbear.net to c/science@hexbear.net
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So I recently found that the University of Minnesota has an Open Textbook Library of textbooks that are licensed to be freely downloaded and distributed and figured I'd post the link here for anyone else who likes studying from textbooks and teaching themselves as I do (I've reread my own textbooks repeatedly from years ago because I'm apparently a bit odd as I've been repeatedly told). Is this the right community for that or are there any others that would be good to cross-post to? Was recently reading the sociology textbooks because those are the ones that seem to reference Marx and Engels a bunch.

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submitted 1 week ago* (last edited 1 week ago) by hypercracker@hexbear.net to c/science@hexbear.net

You mean it's all just pension fraud?

astronaut-1

In Okinawa, the best predictor of where the centenarians are is where the halls of records were bombed by the Americans during the war.

michael-laugh

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submitted 2 weeks ago by UlyssesT@hexbear.net to c/science@hexbear.net

Is it possible to learn this power? anakin-padme-1

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submitted 3 weeks ago by Tychoxii@hexbear.net to c/science@hexbear.net

In places where bat populations crashed, farmers sprayed more insecticides, and baby mortality spiked - 05 SEP 2024 - Erik Stokstad

https://www.science.org/content/article/my-jaw-dropped-bat-loss-linked-death-human-infants

In 2006, bats throughout New England began dying en masse from a mysterious and incurable fungal disease called white nose syndrome. Over the next decade, their populations plummeted—and humans living nearby suffered, according to a new study.

With fewer predators around, insect numbers increased, leading to farmers spraying about 31% more pesticides, researchers report this week in Science. At the same time, infant mortality in counties increased by 8%. The authors link those deaths to the rise in the use of insecticides, which are known to be dangerous, especially for fetuses and infants.

That link is a “pretty dramatic claim that’s going to get a lot of attention,” says Paul Ferraro, a sustainability scientist at Johns Hopkins University who was not involved with the new work. The study, he says, is the “most convincing evidence to date” linking economic and health impacts with dramatic losses of a wild species.

Bats are good to have around a farm. They provide free pest control, with some species consuming 40% of their body weight each night in insects. The value of this service has been estimated at between $4 billion and $53 billion per year. So, it’s logical to assume farmers might compensate for a loss of bats by spraying more insecticides, says Winifred Frick, chief scientist at Bat Conservation International. Making a watertight case for that assumption, however, isn’t easy.

Eyal Frank, an economist at the University of Chicago, realized that the decline of bat populations due to white nose syndrome presented a kind of natural experiment. Because the disease appeared suddenly and spread rapidly, Frank could compare outcomes in counties where bat populations plummeted with those in similar counties that had not yet been struck.

In the first year after an area was hit by the disease, farmers tended to spray an extra kilogram of insecticide per square kilometer, Frank found. After 5 years, they were spraying 2 kilograms more than before—a 31% increase on average. At the same time, fungicide and herbicide rates did not increase, suggesting the need for more intensive insect control drove the insecticide change.

Frank also looked at infant mortality in all the counties. In places where the bat populations had crashed, deaths due to accident or homicides stayed the same. But other deaths, such as those caused by disease or birth defects, rose 8%. In counties with healthy bat populations, the numbers didn’t shift one way or another. “My jaw dropped,” Frick says.

Several lines of evidence connect pesticides and other agrochemicals to human health risks. Although government regulators assess the potential dangers of these compounds before approving them—and set safety guidelines for their use—farm workers and bystanders can still get exposed when these compounds drift away from a farm or end up in groundwater. Epidemiological studies have linked certain compounds to developmental problems in infants and children, for example. Insecticides, which are often neurotoxic, are often of particular concern.

The increase in deaths is “huge,” says Tracey Woodruff, an environmental health scientist at the University of California San Francisco. The connection is plausible and concerning, she says. In an earlier study, she found an increase in infant mortality of similar magnitude due to worsening air pollution. But a puzzling fact about the new study is that other aspects of infant health, such as birth weight, did not correlate with the bat declines.

Still, other confounding factors might have contributed to the rise in mortality, Ferraro notes. “I wouldn’t change public policy based on this one study.”

Frick says there are signs that some populations of bats are beginning to recover, but it could take decades to return to their previous abundance. Her organization is trying to help by setting up lights to attract more insects to winter hibernation sites to make sure bats are eating their fill. Other conservationists are experimenting with changing ventilation of abandoned mines to make their temperature more favorable to roosting bats.

Meanwhile, the fungus that causes white nose Syndrome continues to spread into the western United States, including California, a major agricultural region.

doi: 10.1126/science.zu56w28

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submitted 3 weeks ago by Wheaties@hexbear.net to c/science@hexbear.net

https://www.livescience.com/animals/birds/mice-on-remote-island-that-eat-albatrosses-alive-sentenced-to-death-by-bombing-scientists-decree

Invasive mice are devouring albatrosses alive on a remote island in the Indian Ocean, so conservationists have come up with an explosive solution — "bombing" the mice.

Mice have been wreaking havoc on Marion Island, between South Africa and Antarctica, for decades. Humans accidentally introduced the mice in the 19th century, and the rodents have since developed a taste for wandering albatrosses (Diomedea exulans) and other threatened seabirds.

The Mouse-Free Marion Project, a collaboration between the South African government and BirdLife South Africa, is trying to raise $29 million to drop 660 tons (600 metric tons) of rodenticide-laced pellets onto the island in winter 2027, AFP news agency reported on Saturday (Aug. 24).

The project plans to send a squad of helicopters to drop the pellets. By striking in winter when the mice are most hungry, the conservationists hope to eradicate the entire mouse population of up to 1 million individuals.

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submitted 3 weeks ago* (last edited 3 weeks ago) by geese_feces@hexbear.net to c/science@hexbear.net

An interdisciplinary team of researchers put a culture of the edible mushroom species Pleurotus eryngii (also known as the king oyster mushroom) in control of a pair of vehicles, which can twitch and roll across a flat surface.

By applying algorithms based on the extracellular electrophysiology of P. eryngii mycelia and feeding the output into a microcontroller unit, the researchers used spikes of activity triggered by a stimulus – in this case, UV light – to toggle mechanical responses in two different kinds of mobile device.

https://youtu.be/5ZkkaM54RH8

https://www.science.org/doi/10.1126/scirobotics.adk8019

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submitted 3 weeks ago* (last edited 3 weeks ago) by kristina@hexbear.net to c/science@hexbear.net

Interesting video, this is far from resolving all the world's issues of course, this is essentially throwing a bunch of plastic in a tube and microwaving it to extreme temperatures, but it can create a ton of graphene (30mg plastic -> 5mg graphene conversion). The proposed use for this graphene is in cement mixes in order to toughen concrete and reduce wear on roads and structures.

The technique uses flash Joule heating (FJH) to heat carbonaceous materials to temperatures over 3000 K in ∼100 ms, producing >90% yields of high quality turbostratic FG (tFG). The high temperatures of FJH result in high purity tFG, since much of the non-carbon atoms are removed through sublimation

Using this much energy is of course problematic, sure, it can get rid of the plastic, but we are largely burning fossil fuels to create this energy. It takes 400-600w of electricity to produce this much graphene, which is certainly a breakthrough for graphene production, at least, because of how labor cheap this is. Its also much cheaper electricity wise than pretty much every pre-existing recycling method, which is certainly a good thing.

In this study, the goal is to broaden the application of APMP to solid precursors, specifically converting microplastics into graphene. In contrast to the traditional method of initiating graphene production from gaseous-phase products, this approach involves the transformation of PE microplastics into gases such as methane, ethylene, and ethane, and then converting them into graphene within the plasma, all in one step. Furthermore, the advantages of microwave-based technologies in terms of energy consumption and cost compared to conventional techniques for recycling or upcycling polymers can be found in recently reported studies.[27-29] Following the successful synthesis of graphene, we also showcase its effectiveness in adsorbing perfluorooctanoic acid (PFOA), facilitated by ultrasonication.

The beauty of this is you don't have deep concerns about offgassing, the plasma captures the most harmful vapors and flash converts them to a graphene powder, which resolves a concern of harmful contaminates to local areas of production. It will mostly offgas H2, Carbon monoxide, and Co2, though the paper doesnt seem to discuss the quantities of each gas it produces. Co2 offgassing is obviously problematic itself if that quantity is very high, you're essentially turning a lot of the 'stored' co2 in plastic into gas in the atmosphere. Based on similar studies, it does seem that it will off gas far more H2 than CO or CO2 though


tl:dr: some scientists got a tube filled it with argon and smashed up microplastics, chucked it in a 500 watt microwave, and got a way to make a lot of money off of graphene synthesis

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submitted 3 weeks ago by git@hexbear.net to c/science@hexbear.net
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submitted 3 weeks ago* (last edited 3 weeks ago) by InevitableSwing@hexbear.net to c/science@hexbear.net
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submitted 1 month ago by someone@hexbear.net to c/science@hexbear.net

The two astronauts will remain on the ISS until February 2025, when they'll return with two astronauts on the SpaceX Crew-9 mission that's arriving at the ISS next month.

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submitted 1 month ago by pooh@hexbear.net to c/science@hexbear.net
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