Once again the time has come to gather around and take a well deserved hiatus from the politics of the day. Science talk is here. 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 new solar cell technology greatly boosts efficiency, astronomers unveil portrait of densest known rocky planet, antibiotic resistant bacteria have evolved a unique chemical mechanism, mapping pollutant threats to sea turtles, caterpillars inspire new movements in soft robots, and storage for spent nuclear fuel more crucial than ever. Gather yourselves around. Pull up that comfy chair and bask in the sunshine. There is plenty of room for everyone. Get ready for one more session of Dr. Possum's science education and entertainment.
Featured Stories
Another advance in photovoltaic technology, the creation of a 3-D nanocone-based solar cell platform, was announced this week.
The new solar structure consists of n-type nanocones surrounded by a p-type semiconductor. The n-type nanoncones are made of zinc oxide and serve as the junction framework and the electron conductor. The p-type matrix is made of polycrystalline cadmium telluride and serves as the primary photon absorber medium and hole conductor.
With this approach at the laboratory scale, (researcher) Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency of conventional planar structure of the same materials.
One more time astronomers tell of a new find with the densest known rocky planet
The planet, named 55 Cancri e, is 60 per cent larger in diameter than Earth but eight times as massive. Twice as dense as Earth – almost as dense as lead – it is the densest solid planet known...Approximately 40 light years from Earth, 55 Cancri e orbits a star – called 55 Cancri A – so closely that its year is less than 18 hours long...The temperature on the planet’s surface could be as high as 2,700 degrees Celsius.
Antibiotic resistance among various bacteria is an increasing problem in medicine today.
To solve the chemical mystery of how such bacteria outsmart so many antibiotics, (researcher) Booker and his team investigated how the Cfr protein accomplishes a task called methylation -- a process by which enzymes add a small molecular tag to a particular location on a nucleotide -- a molecule that is the structural unit of RNA and DNA. When this molecular tag is added by a protein called RlmN, it facilitates the proper functioning of the bacterial ribosome -- a gigantic macromolecular machine that is responsible for making proteins that bacteria need to survive. Many classes of antibiotics bind to the ribosome, disrupting its function and thereby killing the bacteria. The Cfr protein performs an identical function as the RlmN protein, but it adds the molecular tag at a different location on the same nucleotide. The addition of the tag blocks binding of antibiotics to the ribosome without disrupting its function.
Sea turtles in their travels accumulate persistent organic pollutants (POPs) and the farther up the Atlantic coast they travel the greater the accumulation.
POPs are a large group of man-made chemicals that, as their name indicates, persist in the environment. They also spread great distances through air and water, accumulate in human and animal tissues, infiltrate food chains, and may have carcinogenic and neurodevelopmental effects. POPs include banned substances such as DDT and toxaphenes, once used as pesticides; polychlorinated biphenyls (PCBs), once used as insulating fluids; and polybrominated diphenyl ethers (PBDEs), once used as flame retardants. While POPs have been recognized for many years as a health threat to loggerhead turtles (Caretta caretta), there is little scientific data available to help understand the nature and scope of the risk.
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Blood plasma concentrations for all of the POPs examined were higher in the transient loggerheads, suggesting that they had eaten prey that were contaminated, such as crabs, in the northern latitudes during previous migrations. Additionally, the loggerheads that travelled farthest north had the highest POP concentrations in their systems.
Robotic scientists searching for new ways for their creations to move about turned to caterpillars for an example of rapid motion of a soft object.
o simulate the movement of a caterpillar, the researchers designed a 10cm long soft-bodied robot, called GoQBot, made out of silicone rubber and actuated by embedded shape memory alloy coils. It was named GoQBot as it forms a “Q” shape before rolling away at over half a meter per second.
The GoQBot was designed to specifically replicate the functional morphologies of a caterpillar, and was fitted with 5 infrared emitters along it side to allow motion tracking using one of the latest high speed 3D tracking systems. Simultaneously, a force plate measured the detailed ground forces as the robot pushed off into a ballistic roll.
In order to change its body conformation so quickly, in less than 100 ms, GoQBot benefits from a significant degree of mechanical coordination in ballistic rolling. Researchers believe such coordination is mediated by the nonlinear muscle coupling in the animals.
The researchers were also able to explain why caterpillars don’t use the ballistic roll more often as a default mode of transport; despite its impressive performance, ballistic rolling is only effective on smooth surfaces, demands a large amount of power, and often ends unpredictably.
Not only did the study provide an insight into the fascinating escape system of a caterpillar, it also put forward a new locomotor strategy which could be used in future robot development.
Spent nuclear fuel is accumulating at a rapid rate around the world. With nuclear energy on the political plate the repercussions from Fukoshima are being felt.
The United States and other countries around the world looking to nuclear power for their energy needs must consider how spent fuel will be handled as they construct new plants and examine existing ones, especially in light of the recent crisis in Japan, according to a comprehensive study from MIT.
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The report, a summary of which was released last September, strongly recommends that an interim solution be developed to remove spent fuel from storage facilities at reactor sites, and move it to regional, medium-term repositories where the fuel can be monitored and protected as it decays over time. Spent fuel loses much of its radioactivity with every passing decade, as the most dangerous radioactive isotopes decay and lose much of their potency during the first 50 years, thus diminishing the problem of long-term storage.
But in the end the problem remains. A new and different solution to the problem of spent nuclear fuel is needed.
Other Worthy Stories of the Week
Self-powering, wireless energy sensors join the internet
Voyager set to enter interstellar space
Impact of cloudy sunlight on energy balance depends on light wavelenght
'Spinstars'--First polluters of the universe
Study links ozone hole to climate change all the way to the equator
Jump in communication skills led to species explosion in electric fishes
Scientists detect early warning signal for ecosystem collapse
As the worm turns its secrets are revealed
Database on environmental impact of major urban ecosystems created
Siberian hot springs reveal ancient ecology
Andromeda's coat of many colors with video
Infants do wake up taller from sleep
Bacteria can grow under extreme gravity
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.
Space.com
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
At Daily Kos:
This Week in Science by DarkSyde
Overnight News Digest:Science Saturday by Neon Vincent. OND tech Thursday by rfall.
Pique the Geek by Translator Sunday evenings about 9 Eastern time
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
A More Ancient World by matching mole
Astro Kos
SciTech at Dkos.
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive.
![](http://i96.photobucket.com/albums/l176/sedalia066/NASA/thewaxinggibbousmoon.jpg)
The Waxing Gibbous Moon, NASA, Public Domain