September 8, 2010, 7:21 AM CT

Plant Nutrients from Wastewater

Nitrogen, phosphorous and potassium - there are valuable nutrients contained in wastewater. Unfortunately, these essential nutrients are lost in conventional wastewater therapy plants. This is the reason why scientists at Fraunhofer have been working on processes for regaining these nutrients in the form that can be used for agriculture. They are showcasing their work at Fraunhofer's stand at the IFAT ENTSORGA fair (September 13-17 in Munich, Gera number of).

Plants cannot thrive without nutrients such as nitrogen, phosphorous or potassium, therefore farmers commonly use organic and industrially manufactured mineral fertilizers to supply wheat, maize and others with these vital substances. In future, the need for nutrients will be soaring because we will only be able to supply the world's growing population with food and cover surging demands for biofuels by using fertilizers. Logically, that causes the prices for these nutrients to skyrocket. But that is not the only problem. The deposits of rock phosphates mandatory for manufacturing phosphate fertilizers are becoming increasingly scarce. The scientists at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart, Gera number of are working at alternatives. They want to recover these essential nutrients from wastewater......... Posted by: Erica      Read more         Source

September 1, 2010, 7:11 AM CT

Free as a bird?

It may seem like birds have the freedom to fly wherever they like, but scientists at the University of Missouri have shown that what's on the ground has a great effect on where a bird flies. This information could be used by foresters and urban planners to improve bird habitats that would help maintain strong bird populations.

"Movement of individuals influences nearly every aspect of biology, from the existence of a single population to interactions within and among species," said Dylan Kesler, assistant professor in fisheries and wildlife at the University of Missouri's School of Natural Resources. "Movement determines where individual birds procreate. How they spread across the landscape affects who meets whom, which in turn dictates how genes are spread".

Kesler has observed that non-migrating resident birds tend to travel over forest "corridors," which are areas protected by trees and used by wildlife to travel. Birds choose to travel over forests because they can make an easier escape from predators as well as find food. Man-made features such as roads, as well as gaps forests from agriculture or rivers, can restrict birds to certain areas. When forests are removed, bird populations become isolated and disconnected, which can lead to inbreeding and weaker, more disease-prone birds......... Posted by: Kelly      Read more         Source

September 1, 2010, 7:08 AM CT

Effects of Sound on Marine Life

A combination of the biology of marine mammals, mechanical vibrations and acoustics has led to a breakthrough discovery allowing researchers to better understand the potential harmful effects of sound on marine mammals such as whales and dolphins.

An international team of scientists from San Diego State University, UC San Diego, and the Kolmården Zoo in Sweden has developed an approach that integrates advanced computing, X-ray Computerized axial tomography scanners, and modern computational methods that give a 3D simulated look inside the head of a Cuvier's beaked whale.

"Our numerical analysis software can be used to conduct basic research into the mechanism of sound production and hearing in these whales, simulate exposure at sound pressure levels that would be impossible on live animals, or assess various mitigation strategies," said Petr Krysl, a UC San Diego structural engineering professor who developed the computational methods for this research. "We think that our research can enable us to understand, and eventually reduce, the potential negative effects of high intensity sound on marine organisms."

The results of this research were recently published in a PLoS ONE article entitled, "A New Acoustic Portal into the Odontocete Ear and Vibrational Analysis of the Tympanoperiotic Complex" by Krysl, Ted W. Cranford, an adjunct professor of research in biology at San Diego State University; and Mats Amundin, a researcher at Sweden's Kolmården Zoo. Sponsors of the research include the office of the Chief of Naval Operations (CNO), Environmental Readiness Division......... Posted by: Kelly      Read more         Source

August 27, 2010, 7:28 AM CT

Complex interactions keep pests under control

Proponents of organic farming often speak of nature's balance in ways that sound almost spiritual, prompting criticism that their views are unscientific and naïve. At the other end of the spectrum are those who see farms as battlefields where insect pests and plant diseases must be vanquished with the magic bullets of modern agriculture: pesticides, fungicides and the like.

Which view is more accurate? A 10-year study of an organic coffee farm in Mexico suggests that, far from being romanticized hooey, the "balance and harmony" view is on the mark. Ecologists John Vandermeer and Ivette Perfecto of the University of Michigan and Stacy Philpott of the University of Toledo have uncovered a web of intricate interactions that buffers the farm against extreme outbreaks of pests and diseases, making magic bullets unnecessary. Their research is described in the July/recent issue of the journal BioScience.

The major players in the system-several ant species, a handful of coffee pests, and the predators, parasites and diseases that affect the pests-not only interact directly, but some species also exert subtle, indirect effects on others, effects that might have gone unnoticed if the system had not been studied in detail.

A key species in the complex web is the tree-nesting Azteca ant (Azteca instabilis). The ants aren't particular about the kind of tree they live in, but for some reason their nests are found in only about 3 percent of shade trees on the farm, and ant-inhabited trees aren't randomly distributed-they're found in clumps......... Posted by: Erica      Read more         Source

August 26, 2010, 11:16 PM CT

Ants use multiple antibiotics as weed killers

Research led by Dr Matt Hutchings and published recently in the journal BMC Biology shows that ants use the antibiotics to inhibit the growth of unwanted fungi and bacteria in their fungus cultures which they use to feed their larvae and queen.

These antibiotics are produced by actinomycete bacteria that live on the ants in a mutual symbiosis.

Eventhough these ants have been studied for more than 100 years this is the first demonstration that a single ant colony uses multiple antibiotics and is reminiscent of the use of multidrug treatment to treat infections in humans.

The work, which was funded by the UK Medical Research Council, has also identified a new antibiotic that could be used to treat fungal infections.

Fungiculture in the insect world is practiced by ants, termites, beetles and gall midges.

Dr Hutchings' research investigates the Acromyrmex octospinosus leaf cutter ant, endemic in South and Central America and the southern US. These ants form the largest and most complex animal societies on earth with colonies of up to several million individuals. The garden worker ants researched were collected from three colonies in Trinidad and Tobago.

Dr Hutchings said: "This was really a fun project which started with a PhD student, Joerg Barke, streaking leaf-cutting ants onto agar plates to isolate antibiotic producing bacteria. Joerg, with his colleagues Ryan Seipke and Sabine Gruschow, really pushed this project forwards and made these major discoveries. They really deserve most of the credit for this work"......... Posted by: Kelly      Read more         Source

August 26, 2010, 11:06 PM CT

Genome Comparison of Ants

By comparing two species of ants, Shelley Berger, PhD, the Daniel S. Och University Professor at the University of Pennsylvania, and his colleagues Danny Reinberg, PhD, New York University, and Juergen Liebig, PhD, Arizona State University, have established an important new avenue of research for epigenetics -- the study of how the expression or suppression of particular genes affects an organism's characteristics, development, and even behavior.

Ants, the new model system used in this study, organize themselves into caste-based societies in which most of the individuals are sterile females, limited to highly specialized roles such as workers and soldiers. Only one queen and the relatively small contingent of male ants are fertile and able to reproduce. Yet despite such extreme differences in behavior and physical form, all females within the colony appear to be genetically identical.

Berger, who directs Penn's Epigenetics program, and his colleagues think that epigenetic mechanisms - chemical modifications to DNA and its supporting proteins that affect gene expression - appears to be critical in establishing such broad variations in behavior and morphology that arise in individuals, despite having the same genome.

As per a research findings published in Science this week, Berger, her Penn colleagues, and a diverse international team of collaborators including ant biologists, geneticists, and biochemists from Arizona State, NYU, Howard Hughes Medical Institute, and the Chinese Academy of Sciences, showed how differences in gene expression between two ant species, the Florida carpenter ant (Camponotus floridanus) and Jerdon's jumping ant (Harpegnathos saltator), correlate with separate castes in each......... Posted by: Kelly      Read more         Source

August 26, 2010, 7:22 AM CT

Move closer to making any crop drought-tolerant

Drought-tolerant crops have moved closer to becoming reality.

A collaborative team of researchers has made a significant advance on the discovery last year by the University of California, Riverside's Sean Cutler of pyrabactin, a synthetic chemical that mimics a naturally produced stress hormone in plants to help them cope with drought conditions.

Led by scientists at The Medical College of Wisconsin, the researchers report in Nature Structural & Molecular Biology (online) on Aug. 22 that by understanding how pyrabactin works, other more effective chemicals for bringing drought-resistance to plants can be developed more readily.

Abscisic acid versus pyrabactin

Plants naturally produced a stress hormone, abscisic acid (ABA), in modest amounts to help them survive drought by inhibiting growth. ABA has already been commercialized for agricultural use. But it has at least two disadvantages: it is light-sensitive and costly to make.

Pyrabactin, conversely, is relatively inexpensive, easy to make, and not sensitive to light. But its drawback is that, unlike ABA, it does not turn on all the "receptors" in the plant that need to be activated for drought-tolerance to fully take hold.

Lock and key

A receptor is a protein molecule in a cell to which mobile signaling molecules such as ABA or pyrabactin, each of which turns on stress-signaling pathways in plants may attach. Commonly at the top of a signaling pathway, the receptor functions like a boss relaying orders to the team below that then proceeds to execute particular decisions in the cell......... Posted by: Erica      Read more         Source

August 25, 2010, 7:08 AM CT

Make Way for Ducklings

Parent birds know best when it comes to taking care of their babies. But, when food gets scarce and they are forced to fly longer distances to grab a bite, "egg sitting" time drops off. What impact does this have on their brood?

"I guess everybody, from a human health perspective, knows that what a mother does during pregnancy can have all sorts of effects on her babies," says Bill Hopkins, an associate professor in the Department of Fisheries and Wildlife Sciences at Virginia Tech. He is holding a duckling in his hand. It's one of a number of he and his team are studying. "We study how these little guys can be affected by the things that mom does".

A member of his research team, Sarah DuRant, examines an egg. "If you look really closely," she says, "you can see the embryo moving".

With the support of the National Science Foundation (NSF), ecologists Hopkins and DuRant are studying wood ducks to better understand the impact of mom's nesting behavior on her ducklings and their ability to survive.

"How much time a female spends on her nest is going to influence the temperature that the nest is at," notes DuRant. The scientists incubate eggs at different temperatures to simulate warmer and cooler nesting conditions. "What we're interested in are very, very subtle changes in temperature, maybe a degree Celsius at most," adds Hopkins......... Posted by: Kelly      Read more         Source

August 25, 2010, 7:06 AM CT

Glue That Holds Oyster

Oyster reefs are on the decline, with over-harvesting and pollution reducing some stocks as much as 98 percent over the last two centuries.

With a growing awareness of oysters' critical roles filtering water, preventing erosion, guarding coasts from storm damage, and providing habitat for other organisms, scientists have been investigating how oyster reefs form in order to better understand the organisms and offer potential guidance to oyster re-introduction projects.

At the same time, scientists have been studying marine animals' various adhesives, uncovering fundamental properties that could yield new innovations from replacements for medical sutures to surface coatings that keep waterborne craft from picking up marine hitchhikers.

Now, scientists from Purdue University and the University of South Carolina have shown that oysters produce a unique adhesive material for affixing themselves to each other, a cement that differs from the glues used by other marine organisms.

The scientists are presenting their findings at the 2010 Annual Meeting of the American Chemical Society in Boston, Mass., on Aug. 24, and will publish their results in the Sept. 15, 2010, issue of the Journal of the American Chemical Society. (The article is available online now.)......... Posted by: Kelly      Read more         Source

August 25, 2010, 7:01 AM CT

Evolutionary response to climate change

Researchers at the University of Oregon have determined the fine-scale genetic structure of the first animal to show an evolutionary response to rapid climate change.

They used a high-throughput sequencing technique called Restriction-site Associated DNA (RAD) tagging to make the discovery.

Their results, which focus on the pitcher plant mosquito, Wyeomyia smithii, are published this week in the journal Proceedings of the National Academy of Sciences (PNAS).

RAD tagging is an effective and straightforward way of barcoding sections of genomic material, much as grocery items are coded at the local supermarket, say the scientists.

"This project demonstrates the power of genomics technologies, which can provide new knowledge about the vast array of Earth's species," says Sam Scheiner, program director in the National Science Foundation (NSF)'s Division of Environmental Biology, which funded the research.

"Eventhough this small mosquito has become the poster child for genetic response to climate change," says William Bradshaw, one of the paper's co-authors, "its evolution during post-glacial invasion of North America has been a question."

Using the RAD-Tag approach, the researchers have demonstrated that post-glacial populations of Wyeomyia smithii originated from a southern Appalachian Mountain refugium after recession of the Laurentide Ice Sheet some 22,000 to 19,000 years ago......... Posted by: Janet      Read more         Source