Howard Hughes Medical Institute – The brain excels at integrating information from past experiences to guide decision-making in new situations. But in certain circumstances, random behavior may be preferable. An animal might have the best chance of avoiding a predator if it moves unpredictably, for example.
When faced with a weak competitor, the animals made strategic choices based on the outcomes of previous trials. But when a sophisticated competitor made strong predictions, the rats ignored past experience and made random selections in search of a reward. more> http://tinyurl.com/knpaxcw
By Lynn Yarris – The cellular signaling networks of living cells start with receptor proteins residing on a cell’s surface that detect and interact with the environment. Signals from these receptors are transmitted to chemical networks within the cell that process the incoming information, make decisions, and direct subsequent cellular activities.
“Although cellular signaling networks perform logical operations like a computer microprocessor, they do not operate in the same way,” Jay Groves, a chemist with Berkeley Lab’s Physical Biosciences Division and UC Berkeley’s Chemistry Department, says. “The individual computational steps in a standard computer are deterministic; the outcome is determined by the inputs. For the chemical reactions that compose a cellular signaling network, however, the molecular level outcomes are defined by probabilities only. This means that the same input can lead to different outcomes.” more> http://tinyurl.com/osa5jj9
R&D – Adhesion is an extremely important factor in living nature: insects can climb up walls, plants can twine up them, and cells are able to adhere to surfaces.
“We discovered that the actual moment of detachment—or more precisely: the moment when a defect in the contact area starts to develop up to its complete separation—lasts only a few micro-seconds.”
“This can be achieved only if a homogeneous stress distribution exists between the mushroom-shaped adhesive element and the surface,” Lars Heepe explains. Reaching such high speeds in this short time requires very much elastic energy, which can only be stored when stress in contact is homogeneously distributed. more> http://tinyurl.com/mj89lsp
R&D Magazine – The enormously diverse complexity seen amongst individual species within the animal kingdom evolved from a surprisingly small gene pool. For example, mice effectively serve as medical research models because humans and mice share 80% of the same protein-coding genes. The key to morphological and behavioral complexity, a growing body of scientific evidence suggests, is the regulation of gene expression by a family of DNA-binding proteins called “transcription factors.” Now, a team of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley has discovered the secret behind how one these critical transcription factors is able to perform—a split personality. more> http://tinyurl.com/bc5ahuu
Posted in Nature, Science, Technology
Tagged Berkeley, Biology, DNA, DNA-binding protein, Gene, Lawrence Berkeley National Laboratory, Physics, Regulation of gene expression, United States Department of Energy, University of California
R&D Mag – During quorum sensing, bacteria produce, detect, and exchange signaling molecules known as autoinducers. This process is crucial to disease development because it ultimately controls the way that bacteria express “virulence factors“—the molecules that enable the bacteria to colonize a host, evade and compromise the host’s immune response, exit and enter cells, and obtain nutrients.
By studying how to inhibit quorum sensing, scientists may be able create antibacterial pharmaceuticals for a variety of ailments.
Recently, in part due to work performed at NSLS, researchers from Princeton University and the Howard Hughes Medical Institute learned how to block a quorum-sensing mechanism in the bacteria. more> http://twurl.nl/1pn07z?
Posted in Healthcare, Nature, Science, Technology
Tagged American Society for Microbiology, Bacteria, Biology, Health, Howard Hughes Medical Institute, Immune system, Princeton University, Quorum sensing, United States