The energy that comes out of solar panels is renewable, but what about the panels themselves? Today’s leading solar panels owe their high sunlight-to-electricity conversion rates to the use of rare elements, such as indium, gallium and selenium. But if current production trends continue unchecked, supplies of indium in particular will be depleted in less than a decade. The pressure is on to find a way of making solar power even more sustainable.
The strongest ‘pound for pound’ muscle is the uterus: it weighs around 2 pounds but during childbirth can exert a downward force of 400 Newtons, which is one hundred times as strong as gravity and equivalent to the power in a fully extended modern longbow.
I need masculism because I am afraid.
you should be
“Participants rated their sexual orientation on a 10-point scale, ranging from gay to straight. Then they took a computer-administered test designed to measure their implicit sexual orientation. In the test, the participants were shown images and words indicative of hetero- and homosexuality (pictures of same-sex and straight couples, words like “homosexual” and “gay”) and were asked to sort them into the appropriate category, gay or straight, as quickly as possible. The computer measured their reaction times. The twist was that before each word and image appeared, the word “me” or “other” was flashed on the screen for 35 milliseconds — long enough for participants to subliminally process the word but short enough that they could not consciously see it. The theory here, known as semantic association, is that when “me” precedes words or images that reflect your sexual orientation (for example, heterosexual images for a straight person), you will sort these images into the correct category faster than when “me” precedes words or images that are incongruent with your sexual orientation (for example, homosexual images for a straight person). This technique, adapted from similar tests used to assess attitudes like subconscious racial bias, reliably distinguishes between self-identified straight individuals and those who self-identify as lesbian, gay or bisexual. Using this methodology we identified a subgroup of participants who, despite self-identifying as highly straight, indicated some level of same-sex attraction (that is, they associated “me” with gay-related words and pictures faster than they associated “me” with straight-related words and pictures). Over 20 percent of self-described highly straight individuals showed this discrepancy. Notably, these “discrepant” individuals were also significantly more likely than other participants to favor anti-gay policies; to be willing to assign significantly harsher punishments to perpetrators of petty crimes if they were presumed to be homosexual; and to express greater implicit hostility toward gay subjects (also measured with the help of subliminal priming). Thus our research suggests that some who oppose homosexuality do tacitly harbor same-sex attraction.”
New study indicates homophobia is often a result of repressed homosexual feelings, validating what Freud posited in his concept of “reaction formation,” in which we lash out against others’ expressions of what we loathe in ourselves.
The above is via explore-blog, and it’s a long and fancy way of saying that (at least according to this study) homophobia is often associated with repressed homosexual feelings. This work will be appearing in the next issue of Journal of Stuff Everyone Knows But Couldn’t Quite Prove Until Now.
according to the nytimes op-ed linked above, it’s actually the Journal of Personality and Social Psychology and they included the following heavy caveat:
It’s important to stress the obvious: Not all those who campaign against gay men and lesbians secretly feel same-sex attractions. But at least some who oppose homosexuality are likely to be individuals struggling against parts of themselves, having themselves been victims of oppression and lack of acceptance. The costs are great, not only for the targets of anti-gay efforts but also often for the perpetrators. We would do well to remember that all involved deserve our compassion.
still, pretty interesting stuff!
Self-healing “artificial leaf” produces energy from dirty water
April 10, 2013
Back in 2011, scientists reported the creation of the “world’s first practical artificial leaf” that mimics the ability of real leaves to produce energy from sunlight and water. Touted as a potentially inexpensive source of electricity for those in developing countries and remote areas, the leaf’s creators have now given it a capability that would be especially beneficial in such environments – the ability to self heal and therefore produce energy from dirty water.
While the leaf mimics a real leaf’s ability to produce energy from sunlight and water, it doesn’t mimic the method real leaves rely on, namely photosynthesis. Instead, as described by Daniel G. Nocera, Ph.D. who led the research team, the artificial leaf is actually a simple wafer of silicon coated in a catalyst that, when dropped into a jar of water and exposed to sunlight, breaks down water into its hydrogen and oxygen components. These gases can be collected as they bubble up through the water to be used for fuel to produce electricity in fuel cells.
Because bacteria can build up on the leaf’s surface and stop the energy production process, previous versions of the device required pure water. Now Nocera’s team has found that some of the catalysts developed for the artificial leaf actually heal themselves, meaning the process can work with dirty water.
“Self-healing enables the artificial leaf to run on the impure, bacteria-contaminated water found in nature,” Nocera said. “We figured out a way to tweak the conditions so that part of the catalyst falls apart, denying bacteria the smooth surface needed to form a biofilm. Then the catalyst can heal and re-assemble.”
Where similar devices are expensive to manufacture due to the use of rare and expensive metals and complex wiring, Nocera’s artificial leaf uses cheaper materials and a simple “buried junction” design that he says would make it cheaper to mass produce. Additionally, less than one liter (0.25 gal) of water is enough to produce around 100 watts of electricity 24 hours a day. And while it isn’t necessarily the most efficient form of electricity generation, Nocera likens the approach to “fast-food energy.”
“We’re interested in making lots of inexpensive units that may not be the most efficient, but that get the job done. It’s kind of like going from huge mainframe computers to a personal laptop. This is personalized energy.
“A lot of people are designing complicated, expensive energy-producing devices, and it is difficult to see them being adopted on a large scale,” he added. “Ours is simple, less expensive, and it works.”
Nocera believes the artificial leaf is likely to find its first use in individual homes in areas that lack traditional electric production and distribution systems. As well as being cheaper than solar panels, because the artificial leaf doesn’t directly generate electricity, but produces hydrogen and oxygen that can be stored, the electricity could be generated for use at night.
The research team hopes to integrate the artificial leaf with technology for converting the hydrogen into a liquid fuel to power everything from traditional portable electric generators to cars.
Nocera described the artificial leaf at the 245th National Meeting & Exposition of the American Chemical Society that is currently being held in New Orleans.
Today’s guest and author of Gulp: Adventures on the Alimentary Canal, Mary Roach in Popular Science:
Taste is a sort of chemical touch. Taste cells are specialized skin cells. If you have hands for picking up foods and putting them in your mouth, it makes sense for taste cells to be on your tongue. But if, like flies, you don’t, it may be more expedient to have them on your feet. “They land on something and go, ‘Ooh, sugar!’ ’’ Rawson does her best impersonation of a housefly. “And the proboscis automatically comes out to suck the fluids.” Rawson has a colleague who studies crayfish and lobsters, which taste with their antennae. “I was always jealous of people who study lobsters. They examine the antennae, and then they have a lobster dinner.”
The study animal of choice for taste researchers is the catfish, simply because it has so many receptors. They are all over its skin. “They’re basically swimming tongues,” says Rawson. It is a useful adaptation for a limbless creature that locates food by brushing up against it; many catfish species feed by scavenging debris on the bottom of rivers.
I try to imagine what life would be like if humans tasted things by rubbing them on their skin. Hey, try this salted caramel gelato—it’s amazing.
Image by Emily Cavalier
Step outside after the first storm after a dry spell and it invariably hits you: the sweet, fresh, powerfully evocative smell of fresh rain. If you’ve ever noticed this mysterious scent and wondered what’s responsible for it, you’re not alone. Back in 1964, a pair of Australian scientists (Isabel Joy Bear and R. G. Thomas) began the scientific study of rain’s aroma in earnest with an article in Nature titled “Nature of Agrillaceous Odor.” In it, they coined the term petrichor to help explain the phenomenon, combining a pair of Greek roots: petra (stone) and ichor (the blood of gods in ancient myth). In that study and subsequent research, they determined that one of the main causes of this distinctive smell is a blend of oils secreted by some plants during arid periods. When a rainstorm comes after a drought, compounds from the oils—which accumulate over time in dry rocks and soil—are mixed and released into the air. The duo also observed that the oils inhibit seed germination, and speculated that plants produce them to limit competition for scarce water supplies during dry times. These airborne oils combine with other compounds to produce the smell. In moist, forested areas in particular, a common substance is geosmin, a chemical produced by a soil-dwelling bacteria known as actinomycetes. The bacteria secrete the compound when they produce spores, then the force of rain landing on the ground sends these spores up into the air, and the moist air conveys the chemical into our noses. “It’s a very pleasant aroma, sort of a musky smell,” soil specialist Bill Ypsilantis told NPR during an interview on the topic. “You’ll also smell that when you are in your garden and you’re turning over your soil.”
Why Pop Rocks Pop
Hard candy (like a lollypop or a Jolly Rancher) is made from sugar, corn syrup, water and flavoring. You heat the ingredients together and boil the mixture to drive off all of the water. Then you let the temperature rise. What you are left with is a pure sugar syrup at about 300 degrees F (150 degrees C). When it cools, you have hard candy.
To make Pop Rocks, the hot sugar mixture is allowed to mix with carbon dioxide gas at about 600 pounds per square inch (psi). The carbon dioxide gas forms tiny, 600-psi bubbles in the candy. Once it cools, you release the pressure and the candy shatters, but the pieces still contain the high-pressure bubbles (look at a piece with a magnifying glass to see the bubbles).
When you put the candy in your mouth, it melts (just like hard candy) and releases the bubbles with a loud POP! What you are hearing and feeling is the 600-psi carbon dioxide gas being released from each bubble.
The Cave of Crystals near Chihuahua, Mexico.
Those giant crystals of gypsum (CaSO4) probably grew to their massive size really slowly in a bath of hot water and dissolved minerals. Now that the water has been pumped out by industrial miners, scientists are free to explore…with the help of some ice-cooled orange jumpsuits: The caves average a termperature of 118 F, and 90 % humidity.
Penguins are colder than their surroundings, turns out. Bonus: psychedelic penguin pics. (via Wired Science)
Images must be woven together from the incoming data from the cameras, cleaned up and given colors that bring out features that eyes would otherwise miss. In this video from HubbleSite, a Hubble-imaged galaxy comes together on the screen.
Art + Science = Awesome
“Every single day in 2013 San Francisco-based artist Klari Reis is creating an abstract painting inside the confines of the humble petri dish, a cylindrical container used by biologists to culture the growth of cells and algae, something the paintings seem to directly resemble.”
Some of the pieces look like fantastic planets or galaxies. They’re each so beautiful and different from each other and it’s only the beginning of March, so we’ve still got nearly 9 months of daily petri dish paintings to enjoy.
Faces of Our Ancestors
Click on images for identification.
About the project:
Scientists have carefully modeled 27 heads of our ancestors based on tiny bone fragments, teeth and skulls collected from around the globe. You can see the heads on display for the first time together at the Senckenberg Natural History Museum in Frankfurt, Germany.
A fantastic journey into our past, and a product of detailed anatomical research and cutting edge digital simulation. This reminds me of a neat evolutionary tale that I went over with my genetics students a couple weeks ago, the genetic origin of the modern human jaw:
You’ll notice as you journey through those faces (click through the gallery to see who’s who) that as we get closer to modern humans, the prominent, muscular jaw shrinks as the brain cavity gets larger. We still see that powerful jaw structure in today’s gorillas and chimpanzees, actually.
A short while before Homo ergaster came on the scene (middle row, far right, originated just under 2 million years ago), our ancestors developed a mutation that inactivated a gene called MYH16. This gene codes for a protein needed to form the powerful jaw muscles that gorillas and chimps use to chew woody plant matter. Without that protein, our ancestors’ jaw muscles became significantly smaller, as did the bones that they attach to.
See how the later skulls have less prominent chins and less of a ridge on the side of the skull? Since the smaller jaw muscles didn’t need thick, hefty bones to hold on to, our skulls could all of a sudden get bigger on top and smaller on the bottom. In other words, our jaws became weaker due to a single mutation, and that single mutation let our brains get bigger in a hurry. And those bigger brains are what gave our ancestors the advantage to continue evolving into you and me. Not everyone agrees with this version of events, but I like it.
I have a hunch that those weaker jaws also led us to start eating cooked meat, rich in brain-enlarging calories, instead of plants … you know, harnessing fire and all that. But I’ll leave it to the paleontologists in the audience to tell me if that’s worth chewing on.
From the department of fun facts comes news that Picasso painted with house paint.
“We were looking into pigments taken from Picasso’s white paint, which from a material perspective is zinc oxide, and we were able to study the impurities that are there,” Dr. Rose said.
Image via statuesneversleep:
Picasso in Paris. I want to be there. Perfect.
Have you ever wondered exactly how big the moon is? We love it when otherwise inconceivably large things are put into a comprehensible perspective. Redditor boredboarder8 wanted to better understand the size of the moon. Armed with the knowledge that “the greatest distance between two points within the contiguous U.S. is 2,892 miles (stretching from Point Arena, CA to West Quoddy Head, ME*)” and that the circumference of the Moon is 6,784 miles, boredboarder8 cleverly placed one measurement atop the other to create this rough approximation.
“It was difficult for me to fathom the size of the moon, thus inspiring the creation of this map. For me, this map puts the scale of the moon much smaller than I previously imagined. But it’s really interesting hearing how others (already grasping the size of the moon) now see the US as larger.
It was one definitely a weird challenge to take a “flat” map of something on a sphere and project it onto a smaller sphere… Certainly take it only as an approximation, but what intrigued me the most is that the distance spanning the continental United States is roughly equal to a little less than half the circumference of the moon.”
So what do you think, does this awesome image make the moon seem larger or smaller than you thought?