Given the choice, many of us would opt for warmer climes during the bleak midwinter. However, most of us cannot afford to move abroad for a few months, so instead we pile on extra layers of clothing to keep warm. Arthropods face much the same dilemma, as they cannot migrate long distances to avoid low winter temperatures – so why are they not killed off by the cold?
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Rabies, a relentless, ancient scourge, may hold a key to defeating another implacable foe: HIV. Scientists at Jefferson Medical College in Philadelphia have used a drastically weakened rabies virus to ferry HIV-related proteins into animals, in essence, vaccinating them against an AIDS-like disease. The early evidence shows that the vaccine – which doesn’t protect against infection – prevents development of disease.
Cartilaginous fishes (sharks, rays, skates, and chimaeras) are the phylogenetically oldest group of living jawed vertebrates. They are also an important outgroup for understanding the evolution of bony vertebrates such as human and teleost fishes. In a new study published online this week in the open access journal PLoS Biology, Byrappa Venkatesh, Sydney Brenner, and colleagues performed survey sequencing (1.4× coverage) of a chimaera, the elephant shark (Callorhinchus milii).
J. B. S. Haldane once famously quipped that "God is inordinately fond of beetles." Results of a study by Mark A. McPeek of Dartmouth College and Jonathan M. Brown of Grinnell College suggest that this fondness was expressed not by making so many, but rather by allowing them to persist for so long. In a study appearing in the April issue of the American Naturalist, McPeek and Brown show that many insect groups like beetles and butterflies have fantastic numbers of species because these groups are so old.
In the event of a nuclear or radiological catastrophe -- such as a nuclear accident or a “dirty bomb” -- thousands of people would be exposed to radiation, with no way of quickly determining how much of the deadly substance has seeped inside their bodies. Scientists at Duke University Medical Center have developed a new blood test to rapidly detect levels of radiation exposure so that potentially life-saving treatments could be administered to the people who need them most.
Researchers at Delft University of Technology can predict how nanostructuring – the extreme reduction of structure – will affect the performance of Li-ion batteries. The nanostructuring of battery materials is likely to be common practice in the future, but it is not always performance-enhancing. The research findings have recently been published in the Journal of the American Chemical Society.
By recognizing sugars, a technique developed by University of Michigan analytical chemist Kristina Hakansson sets the stage for new cancer diagnosis and treatment options.
A growing body of evidence points to assemblies of sugars called glycans attached to proteins on cancer cell surfaces as accomplices in the growth and spread of tumors. Researchers have been keen to characterize these glycans, but traditional analytical methods have not been sufficient.
Cultured fish cell lines and organs such as gills, heart, liver and intestines are being used to investigate the effects of toxins on fish such as freshwater trout and carp in a move to cut down the number of experiments carried out on live fish. Fish Biologists will be presenting new culture methods to help replace the use of live fish for safety testing of chemicals when they meet in Glasgow for the Annual Main Meeting of the Society for Experimental Biology on Sunday 1st April 2007.
Acrylamide is considered to be a probable carcinogen and is produced from foods such as potatoes, coffee, wheat and other cereals when they are cooked at high temperatures. Reduced cooking times and temperatures can help to decrease this potentially harmful chemical but scientists at Rothamsted Research and the University of Reading are trying to tackle this problem from its source by investigating how to reduce the precursors of acrylamide in cereal plants. They will report their findings at the Society for Experimental Biology’s Annual Main Meeting in Glasgow on Sunday 1st April.
Inherent gender differences – instead of more sun exposure – may be one reason why men are three times more likely than women to develop certain kinds of skin cancer, say researchers at Ohio State University Medical Center.
Tree frogs have the unique ability to stick to smooth surfaces even when they are tilted well beyond the vertical - some small tree frogs can even adhere when completely upside down. Conversely when walking or jumping they can detach their toe pads easily. Researchers from the University of Glasgow will present insights into how this fascinating ability is controlled at the Society for Experimental Biology’s Annual Meeting in Glasgow, UK.
Most people know that their nails always go soft and bendy when they immerse them in hot water for any length of time. Conversely when you cut your nails they dry up and become hard and brittle. But why is this? Biologists working with material scientists at the University of Manchester have worked out the best conditions for our nails which may ultimately help the cosmetic industry to mimic the real thing and refine their false nail and varnish products.
Box jellyfish are much more active swimmers than other jellyfish – they exhibit strong directional swimming, are able to perform rapid 180 degree turns, and can deftly move in between objects. So how do they manage to manoeuvre the obstacle course that is in the sea bed? Given that they possess an impressive 24 eyes one would think they would be well equipped for this challenge!
The next time you are struggling to carry your bags home from the supermarket just remember that this could, in fact, be the reason you are able to walk upright on two legs at all! How we have evolved to walk on two legs remains a fundamental but, as yet, unresolved question for scientists. A popular explanation is that it is our ability to carry objects, particularly children, which forced early hominins onto two legs.
Previously, only amorphous polymer materials approached such levels of performance. On the other hand, these “gigantic respiration” and their respiration, which takes place at constant overall shape, is reversible.