One more time here we are at Monday. The time has come to take a well deserved hiatus from all the politics of the day and enjoy some of the fine science news of the past week. New discoveries, new takes on old knowledge, and other bits of news are all available for the perusing in today's information world. Over the fold are selections from the past week from a few of the many excellent science news sites around the world. Today's tidbits include cometary dust in Antartica, new light shone on green plant secrets, chemicals from seaweeds can damage corals, chemical remains of dinobird found, Herschel's HIFI follows the trail of cosmic water, how spiders spin their silk, advances in forensic science aid identification of children's remains, and widespread extinction of lizards by climate change confirmed by study. Come gather around the fire for one more session of Dr. Possum's science education and entertainment.
Featured Stories
In the wilds of central Antartica terrestrial dust particles are pretty rare. But new findings suggest there may other more interesting particles to be found.
Analyses using transmission electron microscopy have shown that the micrometeorites are made up of only very slightly altered organic matter containing small assemblages of minerals. Analysis with an ion microprobe has revealed that its hydrogen isotopic composition shows exceptionally high deuterium/hydrogen (D/H) ratios (around 10 times the value found in terrestrial oceans). Taken all together, the results indicate that the particles very likely come from the most distant bodies in the Solar System, comets.
Solving the riddle of photosynthesis in green plants may move science much farther along in solar energy production.
Green plants and certain bacteria are able to transfer the energy harvested from sunlight through a network of light harvesting pigment-protein complexes and into reaction centers with nearly 100-percent efficiency. Speed is the key – the transfer of the solar energy takes place so fast that little energy is wasted as heat.
Steps are being made to understand this process of quantum entanglement. When the results will be seen in our lives remains to be seen.
Seaweed and coral live side by side in may parts of the ocean. In competing for space we now have evidence chemicals from common seaweeds can damage coral on contact.
The researchers revisited the coral two days, 10 days and 20 days later. In as little as two days, corals in contact with some seaweed species bleached and died in areas of direct contact. In other cases, the effects took a full 20 days to appear – or for some seaweed species, no damaging effects were noted during the 20-day period. Ultimately, as much as 70 percent of the seaweed species studied turned out to have harmful effects – but only when they were in direct contact with the coral.
The harmful chemicals affect only coral in direct contact with the seaweed, suggesting the compounds are not soluble in water, (researcher) Hay noted. The effects – which were measured through photographic image analysis and Pulse-Amplitude-Modulated fluorometry – also varied considerably, with certain seaweeds showing stronger impacts than others.
Progress in paleontology research continues to be made as news of chemical remains of a dinobird, half-dinosaur/half-bird species called Archaeopteryx, is announced.
By recording how ‘bright X-rays’ interacted with the fossil, the team have created maps showing chemical elements which were part of the living animal itself.
The maps ... show that portions of the feathers are not merely impressions of long-decomposed organic material—as was previously believed.
Instead, they include fossilized fragments of actual feathers containing phosphorous and sulfur, elements that compose modern bird feathers.
Trace amounts of copper and zinc were also found in the Dinobird's bones: like birds today, the Archaeopteryx may have required those elements to stay healthy.
The HIFI telescope on Herschel, the Heterodyne Instrument for the Far Infrared, is producing some amazing results.
With its superb resolution, HIFI can target about 40 different lines, each coming from a different transition of the water molecule and thus sensitive to a different temperature. This plethora of water lines in the spectra is anything but redundant information: it actually helps to overcome one of the natural drawbacks of astronomical observations, which yield two-dimensional images due to the projection on the celestial vault. As each line comes from a slightly different area in the interstellar clouds, putting all the information together gives a three-dimensional view of them.
Water trails go all the way from vast star-forming clouds down to stars and planets on much smaller scales. In the proto-planetary discs surrounding stars in the process of forming, water vapour may in fact freeze onto dust grains; these cold grains would then condense into icy planetesimals, the seeds of planet formation.
What is seen is very much like a cosmic MRI examining the region slice by slice.
Spider silk is five times the tensile strength of steel.
Spider silk consists of protein molecules, long chains comprising thousands of amino-acid elements. X-ray structure analyses show that the finished fiber has areas in which several protein chains are interlinked via stable physical connections. These connections provide the high stability. Between these connections are unlinked areas that give the fibers their great elasticity.
In the silk gland the fibers lay in ways that prevent connection.
When the protected proteins enter the spinning duct, they encounter an environment with an entirely different salt concentration and composition. This renders two salt bridges of the control domain unstable, and the chain can unfold. Furthermore, the flow in the narrow spinning duct results in strong shear forces. The long protein chains are aligned in parallel, thus placing the areas responsible for interlinking side by side. The stable spider silk fiber is formed.
Identification of children's remains is difficult as many of the adult features used in forensics do not develop before age 18 years.
The researchers collected craniofacial measurements from the remains of children between the ages of 14 and 16. The researchers then ran the data through modeling software and additional statistical analyses to determine whether children differ significantly from adults in terms of the craniofacial markers that identify a given population.
In addition to forensic applications, the findings also represent a breakthrough for physical anthropologists studying past civilizations. Because craniofacial characteristics are used to examine differences between populations, these findings can help anthropologists advance our understanding of how populations have moved or changed over time. The study shows that anthropologists can now use the remains of children to help get a snapshot of what the population looked like in a specific area – they are no longer limited to using the craniofacial remains of adults.
Reports of the effects of climate change continue to arrive these days. This time an international team surveyed lizard populations and the relationship to their loss with a warming climate.
These lizards need to bask in the sun to warm up, but if it gets too hot they have to retreat into the shade, and then they can't hunt for food. At the extinct sites in the Yucatan, we found that the hours per day they could be out foraging had collapsed. They would barely have been able to emerge to bask before having to retreat.
The researchers found that climate change is occurring too rapidly for lizards to compensate with physiological adaptations to higher body temperatures.
Other Worthy Stories of the Week
Mice show pain on their face just like humans
Novel artificial pancreas controls blood sugar in Type 1 diabetes for more than 24 hours
Weird ultra-small microbes turn up in acidic mine drainage
Quantum mechanics reveals new details of deep earth
Rare Javan rhino found dead in Vietnam
Did phosphorus trigger complex evolution and blue skies
Most distant galaxy ever detected?
14th Century aqueduct found in Jerusalem
Space technology revolutionizes archeology, understanding of Maya
Male cichlid fish may dislike their reflections more than competitors
Death of a star in 3 dimensions
Herschel finds a hole in space
Molecules that act like robots
Plant and animal in direct competition for food
Uninhabited water: Where no microbe has gone before
The world's strongest animal--the tiny copepod
Novel pouch could reduce mother-to-infant HIV infection
Asian ivory trade poses threat to African elephant
For even more science news:
General Science Collectors:
Alpha-Galileo
BBC News Science and Environment
Eureka Science News
LiveScience
New Scientist
PhysOrg.com
SciDev.net
Science/AAAS
Science Alert
Science Centric
Science Daily
Scientific American
Space Daily
Blogs:
A Few Things Ill Considered Techie and Science News
Cantauri Dreams space exploration
Coctail Party Physics Physics with a twist.
Deep Sea News marine biology
Laelaps more vertebrate paleontology
List of Geoscience Blogs
ScienceBlogs
Space Review
Techonology Review
Tetrapod Zoologyvertebrate paleontology
Science Insider
Scientific Blogging.
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
Daily Kos regular series:
Daily Kos University, a regular series by plf515
This Week in Science by DarkSyde
This Week in Space by nellaselim
Overnight News Digest:Science Saturday by Neon Vincent. This week OND by palantir.
Weekend Science by AKMask
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
NASA picture of the day. For more see the NASA image gallery.
Menkhiba and the California Galaxy, NASA, Public Domain