Sunday, June 04, 2006

From Science Daily

Ecosystems With Many Plant Species Produce More And Survive Threats Better:
Ecosystems containing many different plant species are not only more productive, they are better able to withstand and recover from climate extremes, pests and disease over long periods, according to a new study. It is the first experiment to gather enough data--over a sufficient time and in a controlled environment--to confirm a 50-year scientific debate about whether biodiversity stabilizes ecosystems.
Researchers Discover How Bacteria Sense Their Environments:
When humans taste or smell, receptors unique to each nerve cell detect the chemical and send signals to the brain, where many cells process the message to understand what we are smelling or tasting. But a bacterium is just a single cell, and it must use many different receptors to sense and interpret everything around it.
New Cornell research, highlighted on the cover of the May issue of Nature Structural and Molecular Biology, reveals that receptors assemble into a kind of cooperative lattice on a bacterium's surface to amplify infinitesimal changes in the environment and kick off processes that lead to specific responses within the cell.
The researchers suggest that when one receptor detects, for example, a sugar in its environment, communication of some sort triggers an array of linked receptors to rearrange itself, much like when water freezes, all the water molecules assort themselves into a new structure. Through this reorganization, the bacterium's receptor array amplifies the signal that a specific molecule has been sensed outside the cell. This structural shift then activates kinases, or enzymes, within the cell, starting a chain reaction that leads to a response, such as changing how the flagella (or tails) spin. This allows the bacterium to move toward or away from what it has sensed.
Female Genital Mutilation Affects Births: Study:
The first comprehensive study of the effects of female genital mutilation on women and babies during childbirth has been published by leading medical journal, The Lancet.
The study, which provides the first reliable evidence that female genital mutilation can adversely affect birth outcomes, was undertaken by African and international researchers, including Associate Professor Emily Banks from the National Centre for Epidemiology and Population Health at Australian National University.

posted by Bora Zivkovic @ 11:41 AM | permalink | (1 comments) | Post a Comment | permalink