Category Archives: Life Science

Electricity from Bacteria and Wastewater

Researchers harness the power of bacteria by Renee Meiller

In nature, says McMahon, photosynthetic bacteria effectively extract energy from their food — and microbial fuel cells capitalize on that efficiency. “By having the microbes strip the electrons out of the organic waste, and turning that into electricity, then we can make a process of conversion more efficient,” she says. “And they’re very good at doing that-much better than we are with our high-tech extraction methods.”

Through machinery such as plants, photosynthetic bacteria harvest solar energy. They also make products to power microbial fuel cells. “In many ways, this is the best of both worlds — generating electricity from a ‘free’ energy source like sunlight and removing wastes at the same time,” says Donohue. “The trick is to bring ideas from different disciplines to develop biorefineries and fuel cells that take advantage of the capabilities of photosynthetic bacteria.”

The benefit of using photosynthetic bacteria, he says, is that solar-powered microbial fuel cells can generate additional electricity when sunlight is available.

Giant Wasp Nests

Giant wasp nest

Giant nests perplex experts (site broke link so I removed it):

The largest nest Ray has inspected this year filled the interior of a weathered 1955 Chevrolet parked in a rural Elmore County barn. That nest was about the size of a tire in the rear floor seven weeks ago, but quickly spread to fill the entire vehicle, the property owner, Harry Coker, said. Four satellite nests around it have gotten into the eaves of the barn, about 300 yards from his home.

Super-size that nest!, July 21st:

The super-sized nests may contain as many as 100,000. One mammoth nest discovered in South Carolina contained roughly a quarter-million workers and as many as 100 queens.

Ray fears some of these nests may not even reach maximum size until late July or August.

One other finding has intrigued Ray and other researchers: the presence of satellite nests in close proximity to the large nest.

Diplomacy and Science Research

Today more and more locations are becoming viable for world class research and development. Today the following have significant ability: USA, Europe (many countries), Japan, Canada, China, Brazil, Singapore, Israel, India, Korea and Australia (I am sure I have missed some this is just what come to mind as I type this post) and many more are moving in that direction.

The continued increase of viable locations for significant amounts of cutting edge research and development has huge consequences, in many areas. If paths to research and development are blocked in one location (by law, regulation, choice, lack of capital, threat of significant damage to the career of those who would choose such a course…) other locations will step in. In some ways this will be good (see below for an explanation of why this might be so). Promising new ideas will not be stifled due to one roadblock.

But risks of problems will also increase. For example, there are plenty of reasons to want to go carefully in the way of genetically engineered crops. But those seeking a more conservative approach are going to be challenged: countries that are acting conservatively will see other countries jump in, I believe. And even if this didn’t happen significantly in the area of genetically engineered crops, I still believe it will create challenges. The ability to go elsewhere will make those seeking to put constraints in place in a more difficult position than 50 years ago when the options were much more limited (It might be possible to stop significant research just by getting a handful of countries to agree).

Debates of what restrictions to put on science and technology research and development will be a continuing and increasing area of conflict. And the solutions will not be easy. Hopefully we will develop a system of diplomacy that works, but that is much easier said than done. And the United States will have to learn they do not have the power to dictate terms to others. This won’t be an easy thing to accept for many in America. The USA will still have a great deal of influence, due mainly to economic power but that influence is only the ability to influence others and that ability will decline if diplomacy is not improved. Diplomacy may not seem to be a science and engineering area but it is going to be increasingly be a major factor in the progress of science and engineering. Continue reading →

Spider Thread

Spider hanging by its thread

Why a spider hanging from a thread does not rotate

The extraordinary properties of spider’s thread are like a blessing for researchers working on polymers. However, the amazing twisting properties it displays are still not very well understood. How can one explain the fact that a spider suspended by a thread remains completely motionless, instead of rotating like a climber does at the end of a rope?
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Spider’s thread, on the other hand, is very efficient at absorbing oscillations, regardless of air resistance, and retains its twisting properties during the experiments. It also returns to its exact original shape. Certain alloys, such as Nitinol, possess similar properties but must be heated to 90° to return to their original shape.

The amazing properties of spider’s thread have been known for several years: its ductility, strength and hardness surpass those of the most complex synthetics fibers

See more blog posts on life science, biology, etc. and more posts of interest to students and everyone interesting in learning about science.

Altered Oceans: the Crisis at Sea

Extensive LA Times series on Altered Oceans: the Crisis at Sea [sigh, once agin pointy haired bosses broke a links, so they were removed – when will we have web sites run by people that understand basic usability?] by Kenneth R. Weiss and Usha Lee McFarling. Excellent.

Part 1 (of 5): A Primeval Tide of Toxins “Runoff from modern life is feeding an explosion of primitive organisms. This ‘rise of slime,’ as one scientist calls it, is killing larger species and sickening people”

Part 4: Plague of Plastic Chokes the Seas:

Their flight paths from Midway often take them over what is perhaps the world’s largest dump: a slowly rotating mass of trash-laden water about twice the size of Texas.

This is known as the Eastern Garbage Patch, part of a system of currents called the North Pacific subtropical gyre. Located halfway between San Francisco and Hawaii, the garbage patch is an area of slack winds and sluggish currents where flotsam collects from around the Pacific
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Nearly 90% of floating marine litter is plastic — supple, durable materials such as polyethylene and polypropylene, Styrofoam, nylon and saran.

About four-fifths of marine trash comes from land, swept by wind or washed by rain off highways and city streets, down streams and rivers, and out to sea.

I have been unable to find a decent photo of this garbage patch – please post a comment if you know of one.

Tracking Narwhals in Greenland

photo of Narwal pod

Tracking Narwhals in Greenland:

From August 2006 to March 2007, scientists from the University of Washington and the Greenland Institute of Natural Resources will instrument 8-10 narwhals with satellite-linked time-depth-temperature recorders to track whale movements, diving behavior, and ocean temperature structure in Baffin Bay. The instruments will collect water column temperature profiles in the pack ice to more than 1500 meters in depth when narwhals make a fall migration from north Greenland to their wintering grounds in Baffin Bay. Narwhals have never been observed or studied in their winter habitat in central Baffin Bay due to dense ice cover, offshore location, and logistics, so this is a very exciting opportunity for all participants.

A collection of inquiry-and National Science Education Standards-based lessons plans for grades 5-12 that have been specifically designed for this expedition..

Narwhal whales (Monodon monoceros) have been called the unicorn whale due to the tooth that grows strait out from their head up to 8 feet. More information via NOAA also see: A Whale’s Amazing Tooth.

photo: A pod of narwhals from northern Canada, August 2005 – larger

Drug Resistant Bacteria More Common

Drug-resistant germs more common in USA by Anita Manning:

Drug-resistant bacteria that were rare just six years ago now are the most common cause of skin and soft-tissue infections treated in emergency rooms at 11 hospitals across the USA, a study finds.

Researchers at UCLA and the Centers for Disease Control and Prevention found that methicillin-resistant Staphylococcus aureus, or MRSA, accounted for 59% of skin infections overall, from 15% at a hospital in New York to 74% at one in Kansas City, Mo.

The finding suggests that doctors should consider drug resistance as a factor when diagnosing and treating skin infections, says Rachel Gorwitz of the CDC, a co-author of a study in today’s New England Journal of Medicine.

This is another sign of the increasing health threat posed by drug resistant bacteria. The problem of drug resistant bacteria is made much worse by the improper use of anti-biotics.

Related:

Sea “Spiders” Suck on Prey

Vampire sea spiders suck on prey

Weird spider-like creatures that live at the bottom of the ocean and use a ‘straw’ to suck on their prey are baffling scientists.

These sea spiders, some of which are blind, are defying scientific classification.
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She has been using DNA and morphology to construct a family tree, using 60 species of sea spiders from all over the world.

Interesting stuff. Related posts: Ocean Life – Photos of Live Deep-Sea Giant – Incredible Insects – Cat Family Tree – Evolution in Darwin’s Finches – Two Butterfly Species Evolved Into Third

Brain Development Gene is Evolving the Fastest

Fastest-evolving human gene linked to brain boost by Gaia Vince

A study of differences between the human and chimp genomes has identified a gene associated with neural growth in the cerebral cortex – the part of the brain involved in processing thoughts and learning – as having undergone “accelerated evolutionary change”.

Katherine Pollard and colleagues at the University of California Santa Cruz, US, suggest that the fast-changing gene may help explain the dramatic expansion of this part of the brain during the evolution of humans.
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There are only two changes in the 118 letters of DNA code that make up HAR1 between the genomes of chimps and chickens. But chimps and humans are 18 letter-changes apart. And those mutations occurred in just five million years, as we evolved from our shared ancestor.