Here we are one more time. Monday arrived right on schedule. The time has come to gather around and take a well deserved hiatus from all 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 worm remote control, monitoring single bacteria without a microscope, scientists plan to bring mammoth back to life, a new method for converting heat waste to electricity, two new species of 'leaping beetles' discovered in New Caledonia, speeding up Mother Nature's very own CO2 mitigation process, aquatic food chain tied to land, and industrial pollutants found in Eastern Lake Erie carp. Gather yourselves. Pull up that comfy chair and sit by the fire. There is plenty of room for everyone. Get ready for one more session of Dr. Possum's science education and entertainment.
Featured Stories
Scientists report the use of an LCD projector to control brain and muscles of tiny organisms such as worms.
For their first experiment, the researchers illuminated the head of a worm at regular intervals while the animal moved forward. This produced a coiling effect in the head and caused the worm to crawl in a triangular pattern. In another experiment, the team scanned light along the bodies of worms from head to tail, which resulted in backward movement when neurons near the head were stimulated and forward movement when neurons near the tail were stimulated.
Additional experiments showed that the intensity of the light affected a worm’s behavior and that several optogenetic reagents excited at different wavelengths could be combined in one experiment to understand circuit functions. The researchers were able to examine a large number of animals under a variety of conditions, demonstrating that the technique’s results were both robust and repeatable.
A new technique of monitoring bacterial growth may allow better treatment and management of infectious diseases.
The AMBR (asynchronous magnetic bead rotation) sensor uses a spherical, magnetic bead that asynchronously spins in a magnetic field. Just as a pencil attached to a child's toy top creates drag that affects the way the top spins, anything attached to the bead slows its rate of rotation. In the current work, the researchers attached individual, rod-shaped Escherichia coli bacteria to individual beads and watched what happened, using the newly developed AMBR sensor.
"When one bacterium gets attached, it's hanging out there like a little hotdog, and it changes the drag tremendously, slowing down the rate of rotation by a factor of four," said (University of Michigan researcher) Kopelman. "If the bacterium grows even a tiny bit, the drag increases even more, and we can monitor that nano-growth by observing changes in the rate of rotation."
"The method can detect growth of as little as 80 nanometers, making it far more sensitive than even a powerful optical microscope, which has a resolution limit of about 250 nanometers," said graduate student Paivo Kinnunen.
The mammoth went extinct about 10,000 years ago but now scientists hope to resurrect the species.
Under the plan, the nuclei of mammoth cells will be inserted into an elephant's egg cells from which the nuclei have been removed to create an embryo containing mammoth genes.
The embryo will then be inserted into an elephant's womb in the hope that the animal will give birth to a baby mammoth.
While scientists have known for a long time that some crystalline materials could be useful in turning heat into electricity a new compound increases the efficiency of the process.
Researchers at Northwestern University have placed nanocrystals of rock salt into lead telluride, creating a material that can harness electricity from heat-generating items such as vehicle exhaust systems, industrial processes and equipment and sun light more efficiently than scientists have seen in the past.
The material exhibits a high thermoelectric figure of merit that is expected to enable 14 percent of heat waste to electricity, a scientific first.
In these times of decreasing species diversity the news of two new species of beetle is welcome indeed.
The team used plant matter remains found in the digestive tract of the insects at the time they were killed in order to extract their DNA at the same time.
According to the study, which has been published in the Journal of Natural History, this technique made it possible to discover that one of the new species, Arsipoda geographica, which measures three millimetres, feeds on a tropical plant in the mountains (Myrsinaceae), while Arsipoda isola, which is the same size, feeds on another plant (Ericaceae) in the southern jungles of the island.
The CO2 produced in natural gas power plants may be transformed by chemistry into beneficial compounds.
In addition to global warming effects, when carbon dioxide is released into atmosphere, a significant fraction is passively taken up by the ocean in a form that makes the ocean more acidic. This acidification has been shown to be harmful to marine life, especially corals and shellfish. (snip) If the carbon dioxide reacted with crushed limestone and seawater, and the resulting solution was released to the ocean, this would not only sequester carbon from the atmosphere, but also would add to ocean alkalinity that would help buffer and offset the effects of ongoing marine acidification. Again, this speeds up the natural CO2 consumption and buffering process offered by carbonate weathering.
New information about zooplanckton (a food source for fish and other aquatic animals) suggests a tie to land not know before.
While it has been assumed that the zooplankton feed almost exclusively on algae, biomass analyses revealed a different story. In both lakes, organic matter that originated on land made up approximately a third of zooplankton biomass. When edible algae were scarce, zooplankton derived a higher percentage of their diet from terrestrial material.
Bad news about pollution is once again being reported as scientists examine carp from Lake Erie.
The two contaminants the scientists studied were polychlorinated biphenyls (PCBs), manmade organic compounds once used in products including motor oils, adhesives, paints, plastics, pigments and dyes, and polybrominated diphenyl ethers (PBDEs), a class of flame-retardants found in common household items including furniture, personal computers, consumer electronics and drapes.
Both PCBs and PBDEs may disrupt the functions of the endocrine system, which secretes hormones that regulate bodily processes such as growth and development, reproduction and response to stress.
The team examined a sample of 18 carp from eastern Lake Erie and detected both pollutants in all the fish. The greatest concentration of PBDE the investigators found was just over 100 nanograms per gram of fish lipid -- a relatively low amount.
Concentrations of PCBs were higher, reaching 15,000 nanograms per gram in the lipid of one specimen. In contrast, 18 "control" carp from two cleaner New York lakes had no detectable level of PCBs.
Other Worthy Stories of the Week
Chandra images torrent of star formation
New evidence for climate impacts on ancient societies
New farming method reduces greenhouse gases, increases farm yields
Scientist finds recipe for making beer around 500 BC
How the size of networks can skyrocket
Organic milk is better for you--no matter the weather
Flooding in Brisbane suburbs
Gardening in space with HydroTropi
Nanotech medicine to rebuild damaged parts of human body
Loss of reflectivity in the Arctic double the estimate of climate models
Pulsating star hosts a giant planet
The Orion Nebula: Still full of surprises
New reactor paves the way for efficiently producing fuel from sunlight
Genetic origin of cultivated citrus discovered
Slime molds are Earth's smallest, oldest farmers
Arctic sea ice controls the release of mercury
Astronomers release the largest color image of the sky ever made
Mountain ranges may act as 'safe haven' for species facing climate change
Bedbug genetic study finds possible pesticide resistant genes
The risks and consequences of video game addiction
New record melt for Greenland ice sheet
Dino-ear sex riddle solved
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
Daily Kos regular series:
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
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive.
Spiral Galaxy M51 seen in infrared light, NASA, Public Domain, Gaseous cloud near galaxy