Knowledge

Under Light, Chameleon-Like Material Changes Color And Shape

2014-04-23 20:51:23 mega-man

People are excellent at making issues which might be one colour. But when you need to in point of fact mix into your atmosphere, you will want to have a subject matter that may trade its look in accordance with its environment–like a chameleon. University of Michigan researchers have created a material imbued with a special type of crystal that can change its shape and color when different wavelengths of light are shone on it, that could be used in the future to create active camouflage

As you can see in the video below, when the light is on, the crystal particles come together to form an “M,” a process that is reversed when the light switches off. 

The material is made up of a semiconducting metallic sheet made of indium tin oxide, which is transparent and used in many types of displays, monitors, and screens, explained Michael Solomon, a chemical engineer at Michigan. Above that rests a layer of solution full of the aforementioned crystals, which are chemically similar to the particles in latex paint and synthesized in Solomon’s lab. When the light turns on, it creates a positive or negative charge in the metallic layer, which the particles either rush toward or away from, causing a visual change in the surface.

Before, this was impossible to do without having some sort of template or pattern on the underlying material, Solomon told Popular Science. But with this technique, the material is the same, and adjusts its shape to the light. “There’s nothing on the surface that locks you into a certain kind of shape, and it can be turned on and off,” he added. 

Right now the patterns are created by the shape of the light (for example, the M was created by an M-shaped pattern of light). But it may be possible to modify the system so that the colors are reflective of their surroundings, for example. “Though we haven’t done that… I think it’s possible,” Solomon said. The technology could also be used to create signs or fabrics or other materials that change their display or color when they encounter different wavelengths of light.

The chemistry of the crystals is described in a study co-authored by Solomon, doctoral student Youngri Kim, and Aayush Shah, and published today (April 23) in the journal Nature Communications




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Q&A: What Is Feminist Biology?

2014-04-23 20:51:19 mega-man
microscope image showing a fertilized human egg
A Fertilized Human Egg
Wellcome Photography

The College of Wisconsin-Madison is in search of a specific more or less biologist: a feminist one. The college has arrange a fellowship, administered by way of its ladies’s research division, for lifestyles sciences analysis. Whereas it will sound atypical for a social sciences division to host a biologist, the researchers in control of the brand new fellowship are hoping to make it extra of a norm.

Students have lengthy mentioned how gender bias impacts biology analysis. Thirty years in the past, biologists always described sperm as “penetrating” or “burrowing” into passive eggs, even after research showed that eggs play an active role in fertilization… and that sperm’s swimming is too weak to penetrate an egg. Today, scientists know that eggs and sperm recognize each other, grab onto each other, and fuse to form embryos. (So romantic!) But gender bias continues in other branches of biology. Just this month, Popular Science reported on the problems behind neuroscience studies purporting to find “hardwired” differences between men’s and women’s brains.

Naturally, we got intrigued when we learned about the UW-Madison fellowship, which will support one biologist annually for years to come. We talked to one of the fellowship’s administrators, Janet Hyde, about it. Hyde is a psychologist who also directs the university’s Center for Research on Gender and Women.

Popular Science: So this fellowship is for ‘feminist biology.’ What is feminist biology?

Janet Hyde: Feminist biology is a couple things. One is that it’s a critique of past gender bias in biology. So it’s pointing at the problems that have existed with the theories or the methods in traditional biology. And then the second part is that it’s creating new research, new topics, new methods, new theories that remove the gender bias and take women into account fairly.

It just hasn’t progressed as much in biology.

PS: What do you expect your fellow to do?

JH: They have to have a PhD and then they come here to spend two years working on research and teaching.

PS: What are some additional examples of how gender bias has affected biology research?

JH: Some of the best examples are actually in observational studies of primates. Sarah Blaffer Hrdy has a whole book on primate behavior and ways in which she thinks it’s been distorted [in researchers' interpretations]. For example, for many years, they ignored female aggressiveness, female-dominated hierarchies.

There’s a famous study on the size of the corpus callosum, which is a brain region. It has to do with communication between the two hemispheres. The study claimed that this region was larger in women than men, which allowed them more communication between their hemispheres.

It’s consistent with the stereotype of females as being good communicators, right? But when researchers tried to replicate the findings, they couldn’t replicate it.

photo of gelada monkeys siting on a mountain plain in Ethiopia
Matriarchal Gelada Monkeys

PS: Do you know of any other postdocs or departments like this?

JH: To our knowledge, this is the first postdoc of this kind in the nation and probably in the world.

PS: I’m surprised. I’ve heard about some of these examples of gender bias in biology for many years now. (For example, the egg-and-sperm example is from the early 1980s.)

JH: I think that’s a good point. I think what’s happened is feminist analysis has been integrated in some fields really well. You know, in the English department, it’s a whole subfield. In the history department, it’s a whole subfield. It’s partly integrated into psychology. We started in psychology, which is my field, back in the 1970s. And it just hasn’t progressed as much in biology.

But what we’re aiming to do is create a whole new generation of people who will pursue these approaches.

PS: Why do you think it’s been slower in biology?

JH: Well, umm, it’s been slower in the sciences in general and actually, biology is ahead of some other sciences. I think part of the reason is that many scientists believe that science is very objective and factual. Now, that’s actually not—it’s an aspiration. It’s a wonderful aspiration, but it’s actually not true. You know, any scientist has his own point of view and there’s things like confirmation bias. We want to confirm our own theories and so on.

PS: So how have biologists responded to this idea of feminist biology?

JH: I actually find when most biologists hear this, they’re actually receptive. They just didn’t think of this on their own.

PS: When people hear about a biology study, what are some things they can ask themselves to check for gender bias in the study?

JH: The first step is always to say, ‘Does this finding replicate?’ Because we’ve so many of these flash-in-the-pan things where a study gets tons of publicity and there’s so much competition in biology to be first with your breathless finding. So that’s the first question to ask, ‘Has anybody else gotten this?’

There’s certain phrases that tip people off about gender bias. For example, if people do some kind of neuroscience study, let’s say it’s an MRI study with humans. These researchers will often say, ‘This is a hardwired difference between males and females.’

Many scientists believe that science is very objective and factual. It’s a wonderful aspiration, but it’s actually not true.

Well, if these are adults [who are being studied], it’s not hardwired at all, right? They’ve have 20 to 25 years of experience that has shaped their brains. Typically, you don’t find good neuroscientists using the phrase ‘hardwired’ because they know how plastic the brain is. Differential experience between males and females could account for brain differences as easily as any kind of any brain differentiation that depends on hormones or something like that.

You have to look at sample size. There are so many MRI studies looking at structural differences between males and females that are based on teeny-tiny sample sizes. You know, 15 males, 15 females. That research, I think, is getting kind of out of date. Neuroscientists are aiming for larger sample sizes and also well-sampled studies, not just comparisons of male and female college students.

Also, is this conclusion just a reiteration of gender stereotype? And if so, maybe that says it’s a stereotypical interpretation of the findings and that a more critical approach is needed.

PS: Many of these critiqued studies are ones that find differences between female and male biology. Why wouldn’t you expect there to be differences between men and women? They’re obviously biologically different.

JH: Well, you know, there’s lots of phenomena in biology and psychology that seem really obvious and that’s why we do research, to see if those obvious things actually are true.

An example I actually give is that it’s obvious that the sun rotates around the Earth because every morning you see it rise in the east and every evening you see it setting in the west. So some things that seem intuitively obvious actually aren’t right when you have better science to test the idea.

PS: Your first fellow will start this September. What is he or she going to study?

JH: The new postdoc is a woman named Caroline VanSickle and she’s just finished her PhD in biological anthropology at the University of Michigan. She studies fossils from humans and the species immediately preceding humans. Most of these fossils are from South Africa. What she’s studying is the female pelvis in these fossils, which have not been studied. That’s one of those cases where they studied male pelvises and not female pelvises.

She’s studying those and looking at their implications for the evolution of childbirth.

PS: Who is funding this fellowship?

JH: Traditionally, at the University of Wisconsin, is one of the few gender and women’s studies programs that has one of its emphases be on biology. A lot of that results from one of our founding foremothers, Dr. Ruth Bleier, who was very prominent in that field. She died, unfortunately, prematurely.

What happened was we had a big bequest from the estate of this woman, who really wanted to do something. She didn’t specific this in particular, but wanted something along these lines. We came up with this particular idea of this feminist biology postdoc.




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'Mafia' Cuckoos Rule By Fear, Foisting Young On Other Birds

2014-04-23 08:51:22 mega-man
An excellent noticed cuckoo
Yathin S Krishnappa by way of Wikimedia Commons

Nice noticed cuckoos lay their eggs in different birds’ nests, and the host does all of the work of elevating the impostor. But when the brand new foster dad or mum does not cooperate and ditch the brand new arrival, the  the cuckoo every now and then retaliates, destroying the negative birds’ different eggs. Brown-headed cowbirds behave in a similar way. Whaddaya gonna do about it? 

Scientists have puzzled over this habits. This retaliation would not in the beginning seem to beef up the possibility of the cuckoo reproducing, and is rather dangerous in that it could possibly result in a disagreement. One conception to provide an explanation for it’s that the cuckoos are performing like “the mafia,” as described in a learn about published in Scientific Reports–if the host birds fear retaliation, they may raise the cuckoo because it’s better than having all their eggs broken. The same reasoning explains why a shopkeep might unwillingly pay for protection from the mafia, for fear of being roughed up. 

In the new study, researchers mathematically modeled the cuckoo-retaliation and the “mafia” hypothesis, and found that this theory does appear to explain the behavior, as long as two conditions are met: that the cuckoos visit the same nest repeatedly, and that the host birds are capable of learning. The cuckoo makes an offer that can’t be refused, as it were. 

The cuckoo makes an offer that can’t be refused.

“We tested and confirmed the mafia hypothesis, which was controversial among scientists,” said study lead author Maria Abou Chakra, a researcher at the Max Planck Institute for Evolutionary Biology, in a statement

But the parasites don’t always get their way. According to the new model, the interaction between parasite and host is cyclical. Cuckoos do not all exhibit this mafia-like behavior. When non-mafia behavior predominates, hosts who only conditionally-accept cuckoo eggs (after their other eggs are destroyed) are evolutionarily favored. As the researchers wrote:

[But] as the frequency of these conditional accepters increases, it becomes beneficial for the parasites to retaliate against these [conditional-accepting] hosts, and thus, mafia parasites increase in frequency. As soon as mafia parasites are common, it is optimal for hosts to give in without delay, leading to an increase in accepter hosts. This, in turn, makes it needless for parasites to retaliate, leading the parasite population back to the non-mafia strategy.

And so it goes, the circle of life. But darker than the Lion King version.

Another recent study published in Science suggested a different reason why hosts sometimes seem to accept cuckoo eggs: The young impostors excrete a smelly substance that protects hosts from predators




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Watch A Solar Plane Fly Over Milan Countryside [Video]

2014-04-23 08:51:19 mega-man

Plane wings are wide, flat surfaces that virtually at all times face the sky, because of this they’re best mounts for sunlight panels. Constructed by means of Sunlight Flight, a staff of European engineers, the Sunseeker Duo is a two-seater aircraft that flies in simple terms with the aid of solar energy. On December 17, 2013, it accomplished its first flight powered completely by way of its personal battery. Past these days, Sun Flight launched video of that flight.

The plane has the lithe profile and form extra often related to an unpowered glider, and for just right purpose. It can be the most recent prototype in a long line of exclusively solar powered airplanes, all descended from gliders. The very first Sunseeker flew across the U.S. in 1990, and every evolution of the design has retained good gliding ability. As seen in the footage of the flight over the countryside outside of Milan, once the pilot reached a comfortable altitude they were able to turn off the engine and continue gliding, before landing comfortably on the ground.

The Sunseeker Duo’s propeller is located on the tail behind the wing, and when the plane switches to gliding the propeller blades fold back until they are flush with the engine, minimizing drag. It also has a tricycle arrangement of three landing gear, which fold compact inside the body. 

[Sunseeker Duo test flights from Solar Flight on Vimeo.]




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Watch A Solar Plane Fly Over Milan Countryside [Video]

2014-04-23 08:51:18 mega-man

Plane wings are wide, flat surfaces that virtually at all times face the sky, because of this they’re best mounts for sunlight panels. Constructed by means of Sunlight Flight, a staff of European engineers, the Sunseeker Duo is a two-seater aircraft that flies in simple terms with the aid of solar energy. On December 17, 2013, it accomplished its first flight powered completely by way of its personal battery. Past these days, Sun Flight launched video of that flight.

The plane has the lithe profile and form extra often related to an unpowered glider, and for just right purpose. It can be the most recent prototype in a long line of exclusively solar powered airplanes, all descended from gliders. The very first Sunseeker flew across the U.S. in 1990, and every evolution of the design has retained good gliding ability. As seen in the footage of the flight over the countryside outside of Milan, once the pilot reached a comfortable altitude they were able to turn off the engine and continue gliding, before landing comfortably on the ground.

The Sunseeker Duo’s propeller is located on the tail behind the wing, and when the plane switches to gliding the propeller blades fold back until they are flush with the engine, minimizing drag. It also has a tricycle arrangement of three landing gear, which fold compact inside the body. 

[Sunseeker Duo test flights from Solar Flight on Vimeo.]




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Unique Mineral Discovered In Australia

2014-04-23 08:51:15 mega-man
Red mineral
Crystals of putnisite, in red.
P. Elliott et al

A in the past unknown mineral has been revealed in a far flung area in Western Australia. The mineral, named putnisite, seems pink and translucent, and accommodates strontium, calcium, chromium, sulphur, carbon, oxygen and hydrogen, a very unusual combination.

While dozens of new minerals are discovered each year, it is rare to find one that is unrelated to already-known substances. “Most minerals belong to a family or small group of related minerals, or if they aren’t related to other minerals they often are to a synthetic compound–but putnisite is completely unique and unrelated to anything,” said Peter Elliott, co-author of a study describing the new substance and a researcher at the South Australian Museum and the University of Adelaide, in a statement. “Nature seems to be far cleverer at dreaming up new chemicals than any researcher in a laboratory.”

It appears as tiny semi-cubic crystals and is often found within quartz. Putnisite is relatively soft, with a Mohs hardness of 1.5 to 2 (out of 10), comparable to gypsum, and brittle. It’s unclear yet if the mineral could have any commercial applications.

Putnisite was discovered during prospecting for a mine at Lake Cowan in southwestern Australia, and is named after mineralogists Andrew and Christine Putnis. Mineral names are usually proposed by the discoverer, as in this case, but must be approved by the International Mineralogical Association.




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Unique Mineral Discovered In Australia

2014-04-23 08:51:14 mega-man
Red mineral
Crystals of putnisite, in red.
P. Elliott et al

A in the past unknown mineral has been revealed in a far flung area in Western Australia. The mineral, named putnisite, seems pink and translucent, and accommodates strontium, calcium, chromium, sulphur, carbon, oxygen and hydrogen, a very unusual combination.

While dozens of new minerals are discovered each year, it is rare to find one that is unrelated to already-known substances. “Most minerals belong to a family or small group of related minerals, or if they aren’t related to other minerals they often are to a synthetic compound–but putnisite is completely unique and unrelated to anything,” said Peter Elliott, co-author of a study describing the new substance and a researcher at the South Australian Museum and the University of Adelaide, in a statement. “Nature seems to be far cleverer at dreaming up new chemicals than any researcher in a laboratory.”

It appears as tiny semi-cubic crystals and is often found within quartz. Putnisite is relatively soft, with a Mohs hardness of 1.5 to 2 (out of 10), comparable to gypsum, and brittle. It’s unclear yet if the mineral could have any commercial applications.

Putnisite was discovered during prospecting for a mine at Lake Cowan in southwestern Australia, and is named after mineralogists Andrew and Christine Putnis. Mineral names are usually proposed by the discoverer, as in this case, but must be approved by the International Mineralogical Association.




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Britain's Main Nuclear Waste Site Almost Certain To Leak In Near Future, Agency Says

2014-04-22 08:41:33 mega-man
Sellafield nuclear web page
The Sellafield nuclear web page in northwest England. About six kilometers (four miles) to the south is the nuclear waste web page, the Low Stage Waste Repository, the place subject material from Sellafield and in different places is saved.

For the ultimate fifty five years, most of Britain’s low-stage nuclear waste–the more or less subject material utilized in nuclear energy stations etc–has ended up at a repository in northwest England, on the coast close to the Irish Sea. Some areas of the web page are handiest sixteen toes above sea degree. Now not the most effective location to retailer radioactive waste, particularly with rising sea levels, right?

Right. The United Kingdom’s Environment Agency has determined in a reported released to The Guardian that the “dump is virtually certain to be eroded by rising sea levels and to contaminate the Cumbrian coast with large amounts of radioactive waste.” The report also noted, in a somewhat underwhelming fashion, that “it is doubtful whether the location of the [dump] site would be chosen for a new facility for near-surface radioactive waste disposal if the choice were being made now.” Tanks for nuttin’, EA! JK.

It concluded that the 35 million cubic feet (1 million cubic liters) of waste will start leaking on to the shoreline and the coast in “a few hundred to a few thousand years from now.” Environmentalists and some citizens aren’t happy about it, arguing that use of the site is “unethical, unsustainable and highly dangerous.” But the site’s operator says the risks are insignificant. As The Guardian noted

[The] operator, LLW Repository Ltd, said it had introduced new restrictions on the amounts of radioactivity that can be disposed of at the site in order to make sure that radiation doses to people will be “very small” if the wastes are exposed by coastal erosion. 

The company’s head of science and engineering, Dr Richard Cummings, accepted that erosion could start “in a few hundred years.” But he added: “The radioactivity in the wastes will largely have decayed away by this time.”

There is, however, some concern that not all of the waste deposited in the past was “low-level”–meaning it could have come from nuclear submarines and weapons, and thus present a greater hazard. The Environment Agency has already asked the consortium of companies that manage the site to “start preparations to defend the site against floods and erosion,” The Independent reported

[The Guardian




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A Test That Quantifies Basic Language-Learning Ability

2014-04-22 08:41:30 mega-man
photo of a U.S. Air Force cadet writing on a blackboard in a Chinese language class
Educating An Outdated Canine New Phrases
A U.S. Air Pressure Academy cadet on the board in Chinese language type.
U.S. Division of Protection

Unless lately, it can be been used completely in U.S. executive companies and army faculties. However now, a check for a way simply an individual will change into fluent in a international language will be made on hand for civilians. Nautilus calls the test “one of the first civilian benefits to come out of America’s war on terror.”

Nautilus looks at some of the science—and yet-unproven theory—behind the test, called the High Level Language Aptitude Battery, or Hi-LAB. In short, some of the latest thinking posits that some people have better brain hardware for reaching high-level fluency in another language as an adult. You’ve probably heard a lot about how the brain is primed for learning languages in childhood. There’s even evidence that a pill could induce that childlike learning state in adult brains. The Hi-LAB researchers found, however, that certain adults naturally seem to learn language similarly to the way kids do. Hi-LAB is designed to find those adults.

The U.S. military got especially interested in this research after 9/11. Suddenly, military leaders found themselves in dire need of translators for languages quite unlike English, such as Arabic and Pashto. They wanted to train American translators quickly and they didn’t want to waste time on people who were never gonna get there.

Now, the military and Hi-LAB’s creators have released details about the test to the public for the first time, Nautilus reports. Outside of the military, Hi-LAB could pinpoint different adults’ optimal language learning strategies. You could get language lessons tailored just for your brain… whether or not you have the architecture to make you so fluent, your government would want you translating intercepted terrorist messages. But will it work? Even in the military, it’s still too soon to know whether Hi-LAB has helped the American government find and nurture the best adult language learners, Nautilus reports.

[Nautilus]




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Meteors May Have Brought Vitamin B To Earth

2014-04-22 08:41:24 mega-man
Researcher Karen Smith crushing meteorite samples for analysis.
Made in Area
Karen Smith crushing meteorites with a mortar and pestle in Goddard’s Astrobiology Analytical Laboratory to organize them for prognosis. Diet B3 was once present in all eight meteorites analyzed within the find out about.
Karen Smith

Did lifestyles right here start…available in the market? We do not but understand and may just by no means. However there’s compelling proof that I may now not be sitting right here scripting this nowadays, otherwise you studying it, if now not for meteorite-enabled distribution of a easy nutrition billions of years in the past.

Scientists funded through NASA’s Goddard Area Flight Heart have discovered diet B3, a.ok.a. niacin, in a gaggle of eight historic, carbon-wealthy meteorites. And the extra pristine a meteorite is, the extra B3 it incorporates.

The quantity of niacin within the eight meteorites ranged from 30 to 600 elements per billion.

The discovering means that quite a few the Earth’s preliminary niacin provide could have originated in area, right through the cosmic occasions that created the Sunlight Device, and been delivered to earth through meteorites. As soon as right here, pure techniques like erosion degraded the meteorites, leeching that B3 into the setting.

Why is that this a clue to the origins of lifestyles on Earth? Smartly, niacin, often known as nicotinic acid, is a precursor to an amine referred to as nicotinamide adenine dinuclotide (NAD). Amines are resources which can be key to the formation of amino acids, which in flip are constructing blocks for molecular proteins. Molecular proteins are an important to the features that include dwelling organisms, primarily the chemical bits inside our cells that act upon the opposite, reasonably inert bits.

The researchers are cautious to not overstate the case, which was once published this week in the journal Geochimica et Cosmochimica Acta. “It is always difficult to put a value on the connection between meteorites and the origin of life,” says lead researcher Karen Smith of Penn State, in an article on the NASA website. “For example, earlier work has shown that vitamin B3 could have been produced non-biologically on ancient Earth, but it’s possible that an added source of vitamin B3 could have been helpful.”

However, Smith and her colleagues also also found niacin isomers—related substances with the same chemical formula as niacin but with atoms attached in different formations—in the meteorites, at similar concentrations to the niacin. These variants are not used in or created by living processes, so are very unlikely to exist in the meteorites if the B3 they contain came from exposure to Earth-bound life.




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