Any road with a loose surface like or gravel or snow can develop ripples that make driving a very shaky experience. A team of physicists from Canada, France and the United Kingdom have recreated this "washboard" phenomenon in the lab with surprising results: ripples appear even when the springy suspension of the car and the rolling shape of the wheel are eliminated. The discovery may smooth the way to designing improved suspension systems that eliminate the bumpy ride.
"The hopping of the wheel over the ripples turns out to be mathematically similar to skipping a stone over water," says University of Toronto physicist, Stephen Morris, a member of the research team.
The Amazon River has been around for 11 million years ago and in its shape for the last 2.4 million years ago, according to a study on two boreholes drilled in proximity of the mouth of the Amazon River by Petrobras, the national oil company of Brazil.
Until recently the Amazon Fan, a sediment column of around 10 kilometres in thickness, proved a hard nut to crack, and scientific drilling expeditions such as Ocean Drilling Program could only reach a fraction of it. Recent exploration efforts by Petrobras lifted the veil, and sedimentological and paleontological analysis on samples from two boreholes, one of which 4.5 kilometres below sea floor, now permit an insight into the history of both Amazon River and Fan.
In the 1980s, a popular hypothesis was that any number of people were suffering from trauma they knew nothing about; dissociative amnesia, or repressed memories.
At issue is how to prove whether memories of trauma, such as childhood sexual abuse, could be repressed and then resurface later in life. Overzealous therapists and willing victims led to any number of false allegations and the resulting damage to families can't be overstated. Even a hint of child abuse is guilt in the minds of many.
Physicists at the National Institute of Standards and Technology (NIST) have devised a viable way to manipulate a single 'bit' in a quantum processor without disturbing the information stored in its neighbors, using polarized light to create "effective" magnetic fields.
A great challenge in creating a working quantum computer is maintaining control over the carriers of information, the "switches" in a quantum processor while isolating them from the environment. These quantum bits, or "qubits," have the uncanny ability to exist in both "on" and "off" positions simultaneously, giving quantum computers the power to solve problems conventional computers find intractable – such as breaking complex cryptographic codes.
The mystery of a rare bat's unusually large nose has been solved, according to an article in Physical Review Letters.
The adult Bourret's horseshoe bat, known scientifically as the Rhinolophus paradoxolophus meaning paradoxical crest, has a nose roughly 9 millimeters in length but the typical horseshoe bat's nose is half that long, said Rolf Mueller, an associate professor with the Virginia Tech mechanical engineering department and director for the Bio-inspired Technology (BIT) Laboratory in Danville, Va. "This nose is so much larger than anything else," among other bats of the region, he said.
Severe chronic obstructive pulmonary disease (COPD) is associated with lower cognitive function in older adults, according to research from Mount Sinai School of Medicine.
Researchers compared cognitive performance in over 4,150 adults with and without COPD and found that individuals with severe COPD had significantly lower cognitive function than those without, even after controlling for confounding factors such as comorbidities.