Science at Atheist Universe
VIDEO OF THE WEEK: Amazing Footage Of A Chick Embryo: researcher Anna Franz gives us a glimpse of the vascular system of a fertilized chicken embryo by cutting away a small portion of an eggshell and injecting ink into the yolk sac artery. This video won Nikon’s first annual Small World in Motion competition.
For more beautiful, interesting, astonishing, or simply cute videos of our natural world, check out the AVM Video Thread, here.
EARTH SCIENCES: Awe-inspiring Northern lights. Check out this great collection of Northern light pictures, taking by ordinary people living in areas where the sun storms have resulted in the most beautiful Northern light spectacle this winter. This past week, there were two solar storms, back-to-back, resulting in the biggest solar flare in the past 6 years. Solar storms produce a massive amount of charged particles that the Earth's magnetic field deflects towards the poles. The interaction of these charged particles with the atmosphere results in these colorful auroras. Go to the link to see many beautiful photographs! The photo I post here was taken by Bjørn Jørgensen in Grøtfjord, close to Tromsø in northern Noway. He calls it “eagle lights” because they resemble a bird in flight.
COMPUTER SCIENCE/MOLECULAR BIOLOGY: Biological computer can decipher information encrypted in DNA chips. As we all know, DNA in a way stores information. Because of this property, computer scientists have been studying ways to use DNA to build biological computers. A recent collaboration between The Scripps Research Institute (California) and Technion (Israel) has resulted in the creation of a biological computer made from biomolecules. The “computer” could decipher fluorescent images (the logos of both institutions) encrypted on DNA chips. The “hardware” and “software” in the biological computer are biomolecules that activate one another (DNA enzymes) to produce another well-defined molecule, using ATP as the energy source. The “computer” is actually a clear solution of these DNA enzymes + ATP in a tube. Not much to look at. The design is based on a 75-year-old design by mathematician Alan Turing; he had shown that his “Turing machine” could do basically all the calculations in the world. Each step of the biomolecular computer is slower than a normal electronic computer, but because millions of chemical reactions can be done in parallel, it could potentially e very fast. . in addition, biological computers could interact directly with living organisms, since it would not require a separate “interface.”
COGNITIVE NEUROSCIENCE: Working in small groups decreases the cognitive abilities of lower-.... Awareness of social status while working in small groups has a detrimental effect on the cognitive abilities of people aware of being “lower-rank”. Apparently the old joke that a camel is a horse designed by a committee is now endorsed by this study. The team of scientists used fMRI to investigate the effect of knowing the results of a “ranked group IQ” test in people of normal-to-high IQ working in small groups (five people each). At first, working in a group decreased everyone’s cognitive capacity. But eventually, stratifying people in high IQ rank and low IQ rank impacted the abilities of the low IQ ranked people. The fMRI data brain responses in the amygdala (a region of the brain that processes stress and fear). In conclusion, small groups appear to sap the intelligence out of group members, and the effect is exacerbated by perceived lower status within the group.
EVOLUTION: Why zebras have stripes. I'm willing to bet that many of you have wondered why zebras have stripes. It's such a striking, contrasting pattern, that there has to be an evolutionary explanation for it. But up until now, there was much speculation as to what evolutionary advantage could be conferred by stripes, but no real data. But now we have an answer: the striped pattern is unappealing to horseflies! The bites of these tabanid flies have a real health impact on the hosts; therefore being victim of fewer horsefly bites is very likely to have a fitness impact. Hungarian and Swedish scientists using plastic, life sized horse models out in the field have demonstrated that horseflies are much less attracted to the striped pattern than to homogeneous black, brown, grey or white coats. They cleverly designed the coats to be sticky so they could capture how many horseflies had landed on the different coats. Horseflies are known for responding to polarized light, and the light and dark stripes pattern reflect very different polarizations that make the coat much less attractive to the pesky flies. They demonstrated that the stripe widths of zebra coats fall exactly in the range where the striped pattern is most disruptive to the flies. This looks pretty good as an explanation for the selective advantage of a black-and-white striped coat pattern. The only caveat is that it was tested on plastic models on a farm, not in the zebras' natural habitat, where they would encounter tse-tse flies, which are attracted to animals also by their strong odor.
ZOOLOGY: Albino hummingbird. A completely snow-white albino ruby-throated hummingbird (Archilochus colubris) was spotted and photographed in Virginia. This species is the only native hummingbird species from east of the Rocky Mountains. The bird appears to be a true albino since it has pink eyes. Albinism is a genetic condition resulting from lack of production of the pigment melanin. Albinism has been described in many animal species, including mammals, reptiles, but this is the first albino hummingbird to be photographed.
Science bits and news from other sites:
First Neanderthal Cave paintings? Neanderthals were initially thought to have been incapable of creating art; however, recent discoveries of decorative shells and stones are changing the image of the Neanderthal as incapable of creativity. And now Spanish scientists believe that Neanderthals are the authors of striking paintings of seals on the walls of the Neria cave near Malaga, Spain. Radiocarbond dating places the paintings at between 43,500 and 42,300 years old. If this dating is real, these would be the oldest paintings ever discovered, a lot older than the famous Chauvet paintings in the south east of France, which are ~30,000 years old. Dating of the pigments is underway to confirm the age of the paintings. Although the paintings could in theory be made by Homo sapiens, there are no records of modern humans living in Spain that far back, while there are plenty of Neanderthal remains from that age.
The design and geometry of pasta. A fascinating new book by chef Jacob Kenedy in collaboration with graphic designer Caz Hildebrand, Pasta by Design, explored and beautifully illustrates the geometry of pasta, exploring the intricate shapes of more than 90 different types of pasta. In addition to being delicious, versatile and good for you, pasta is a perfect example of great design. The designs have withstood the test of time, and demonstrate human ingenuity in searching for beauty as well as functionality in design. Matching pasta shape and sauce to maximize taste and texture is definitively an art, and a bit of a science, too. The authors took advantage of the science of phylogeny, which is the study of relatedness in nature, to classify 92 different types based on their morphological features, then charts them in a family tree. In the book, each shape is described by a mathematical formula, accompanied by beautiful drawings. The apparently whimsical geometrical shapes and surfaces have been designed specifically to hold or soak up certain sauces or accompaniments: they are not designed just for beauty, but also for function. Allow myself a little pride in my Italian heritage: what a perfect combination of beauty, geometry, and delight for our palates pasta is!
Best DNA haiku ever. And while we are in the mood for combining art and science, there was a contest for DNA haikus at the Boston Globe, and the winner is in my opinion the best DNA haiku ever:
A spiral staircase
Each step makes you what you are
But not who you are
(Go to the site to see the runner-ups.)
5th grader puts together a new molecule, gets authorship on paper. It’s so cool when teachers
stimulate their students and take them seriously. 11 year old Clara Lazen built a model from oxygen, nitrogen, and carbon atoms, using a molecule modeling kit handed to the kids by their teacher, Kenneth Boehr. She asked him if she had built a real molecule, and since he didn’t know, he showed the model to an old college buddy, Robert Zoellner, professor of chemistry at Humbolt State University. It turns out that Clara accidentally built a novel viable molecule. If synthesized, it could store up energy and could potentially be used as an explosive. The molecule is called tetranitratoxycarbon, and unfortunately could not be synthesized with he equipment of Humbolt University’s chemistry program. But Zoellner wrote a paper on the molecule’s structure in the journal Computational and Theoretical Chemistry) on the molecule’s structure and its possible uses, and he listed Clara as a co-author! Clara loves science, especially biology and medicine.
The mechanism of action of healing massages is uncovered. Most of us have experienced the relief that expert kneading of sore muscles bring. Massage's healing touch may have more to do with DNA than with good hands. And now we know why it works: massage turns off the expression of genes that cause inflammation and turns on the expression of genes that help recover from injury. Previous unproven explanations, for example that massage squeezes out lactic acid from sore muscles, should now be discarded. A Canadian scientist, Mark Tarnopolsky (McMaster University) was intrigued by the healing he himself experienced after a sports injury and was determined to find the mechanism. He recruited 11 young men and made them cycle upright until their muscles were sore and tender. Then they received therapeutic massage in only one leg. Small biopsies were taken of their quadriceps muscles before exercise, right after exercise (before massage), and after massage, and they extracted RNA to look at gene expression. Unsurprisingly, there was increased gene expression for cell repair and inflammation after the workout. But the most stunning differences were in the massaged vs. non-massed leg: the massaged legs had increased expression of PGC-1alpha, a gene that contributes to mitochondria build up in muscle cells, and they also had had three times less NFkB, a key regulator that turns on genes associated with inflammation. Consequently, levels of the inflammatory cytokines tumor necrosis factor–α (TNF-α) and interleukin-6 (IL-6) were seen. These lower levels of inflammation mitigate cellular stress resulting from muscle fiber injury. The study found no evidence that the massage helped flush out lactic acid.