It is commonly known that racing cars and bicyclists can reduce air resistance by following closely behind a leader, but researchers from New York University and Cornell University have found the opposite is true with flapping objects, such as flags. Their study, published in the most recent issue of the journal Physical Review Letters, discovered that in a series of flags, the leading flag faces significantly less resistance than do succeeding flags. The finding may alter our understanding of how living flapping creatures, such as birds or fish, move through the air and water.
Passengers check in their suitcases, which are automatically transported away by conveyer belts; moving walkways and escalators run for hours without a break – thousands of gear units rattle away at the major airports. The power consumption is tremendous, in the range of several gigawatt hours per annum. A substantial amount of this is lost through friction. In wind turbines and in cars, too, a percentage of the energy is spent on friction – reducing the efficiency factor accordingly. Novel lubricants that almost eliminate the effect of friction could be the answer.
Ship's propellers, parts for wind energy converters, turbine housings – such large-volume castings can only be produced with special molds. The procedure is elaborate and cost-intensive because foundry workers must still perform most of the work steps manually.
Ninety years after Australian scientists began their race to stop the spread of Spanish flu in Australia, University of Melbourne researchers are hoping records from the 1918 epidemic may hold the key to preventing future deadly pandemic outbreaks.
This month marks the 90th anniversary of the return of Australian WWI troops from Europe, sparking Australian scientists' race to try and contain a local outbreak of the pandemic, which killed 50 million people worldwide.
Like other kinds of cells, immune cells lose the ability to divide as they age because a part of their chromosomes known as a telomere becomes progressively shorter with cell division. As a result, the cell changes in many ways, and its disease fighting ability is compromised.
But a new UCLA AIDS Institute study has found that a chemical from the Astragalus root, frequently used in Chinese herbal therapy, can prevent or slow this progressive telomere shortening, which could make it a key weapon in the fight against HIV.
Philadelphia, PA, November 10, 2008 – With childhood obesity increasing, school administrators and public health officials are reducing availability of sugar-sweetened beverages (SSB) in schools. In a study published in the November/December 2008 issue of the Journal of Nutrition Education and Behavior, researchers found that reduction or elimination of SSB from school menus has little effect on total consumption by adolescents.
SALT LAKE CITY – A group of paleontologists visited the northern Arizona wilderness site nicknamed a "dinosaur dance floor" and concluded there were no dinosaur tracks there, only a dense collection of unusual potholes eroded in the sandstone.
So the scientist who leads the University of Utah's geology department says she will team up with the skeptics for a follow-up study.
The end-stage renal disease (ESRD) Medicare reform measures recently passed by Congress represent the most significant ESRD reforms in decades. These measures and how they will impact the practice of nephrology and patient care will be the topic of a session during the American Society of Nephrology (ASN) 41st Annual Meeting and Scientific Exposition in Philadelphia, Pennsylvania.
Elementary school students will eat more whole grains when healthier bread products are gradually introduced into their school lunches, a new University of Minnesota study shows.
Whole grain breads are strongly recommended as part of a healthy diet, but children and pre-teens won't always eat them. For this study, researchers from the university's department of food science and nutrition monitored how much bread students threw away, and whether that amount increased as the percentage of whole-grain flour in the bread and rolls was gradually increased.
"Net energy is a (mostly) irrelevant, misleading and dangerous metric," says Professor Bruce Dale, editor-in-chief of Biofuels, Bioresources and Biorefining (Biofpr) in the latest issue of the journal published today.
Net energy is a metric by which some scientists attempt to assess the sustainability and ability of alternative fuels to displace fossil fuel but recent debate in Biofpr shows that scientists are undecided on its merits as a tool.