Although hummingbirds are much larger and stir up the air more violently as they move, the way that they fly is more closely related to flying insects than it is to other birds. Now, the most detailed, three-dimensional aerodynamic simulation of hummingbird flight conducted to date has definitively demonstrated that the hummingbird achieves its nimble aerobatic abilities through a unique set of aerodynamic forces that are more closely aligned to those found in flying insects than to other birds.
Rejecting unsuitable romantic partners is easy in hypothetical situations, but not so when considering a face-to-face proposition, a new study shows. “When actually faced with a potential date, we don't like to reject a person and make them feel bad, which is not necessarily something that people anticipate when they imagine making these choices,” says the study’s lead researcher.
We are all familiar with the security hassles that accompany air travel. Now a new type of security detection that uses terahertz radiation is looking to prove its promise. Researchers have developed a room temperature, compact, tunable terahertz source that could lead to advances in homeland security and space exploration. Able to detect explosives, chemical agents and dangerous biological substances from safe distances, devices using terahertz waves could make public spaces more secure than ever.
An intervention that uses music and games to help preschoolers learn self-regulation skills is helping prepare at-risk children for kindergarten, a new study shows. Self-regulation skills -- the skills that help children pay attention, follow directions, stay on task and persist through difficulty -- are critical to a child's success in kindergarten and beyond, said a co-author of the new study.
New research raises concern about potential long-term harmful impact of 'antiretroviral therapy' on in-utero infants whose mothers are HIV-positive, but who are not infected with HIV themselves. The study shows that while the HIV medications have been successful in helping to prevent the transmission of the virus from mother to infant, they are associated with persistently impaired development of heart muscle and reduced heart performance in non-HIV-infected children whose mothers received the medicines years earlier.
Physicians from 60 sites treated 161 heart attack patients with their own bone marrow cells, selected for their healing potential and then reinjected into the heart, in an effort to improve the heart's recovery. Their conclusion? Patients who receive more cells get significant benefits.
Digoxin, a drug commonly used to treat heart conditions, was associated with a 71 percent higher risk of death and a 63 percent higher risk of hospitalization among adults with diagnosed atrial fibrillation and no evidence of heart failure, according to a study.
For the first time, researchers have grown a single atomic layer of tungsten diselenide on a one- atom-thick substrate of graphene with pristine interfaces between the two layers using an industrially scalable technique.
A new device contains a form of vitamin A that controls inflammatory responses, preventing scar tissue formation and promoting wound healing. The soft, porous, and thin elastic material contains an acid form of vitamin A, called a retinoid, which is produced by the body to help cells develop and stay healthy. Synthetic retinoids have been formulated and traditionally used to treat acne and some types of cancer.
In many firms sales people spend as much time negotiating internally for lower prices as they do interacting with customers. A new study finds that firms should allow their sales people to 'waste' energy on internal negotiations. In fact, it says, firms should make the process wasteful on purpose.
Scientists developed a new method which allows to estimate the magnetic field of a distant exoplanet, i.e., a planet, which is located outside the Solar system and orbits a different star. Moreover, they managed to estimate the value of the magnetic moment of the planet HD 209458b.
A survey of older adults in eleven countries found that Americans were sicker than their counterparts abroad, with 68 percent living with two or more chronic conditions and 53 percent taking four or more medications. More Americans, 19 percent, reported cost-related care expenses than residents in other countries -- whereas 83 percent of US respondents had treatment plans they could carry out in their daily lives, one of the highest rates across the surveyed countries.
Drugs that have been used for the past 30 years to treat HIV/AIDS, could be repurposed to treat the dry form of age-related macular degeneration (AMD), a new study suggests. AMD is a progressive condition that is untreatable in up to 90 percent of patients and is a leading cause of blindness in the elderly worldwide. The two forms of AMD, wet and dry, are classified based on the presence or absence of blood vessels that have invaded the retina.
A recent study from the Thai-Myanmar border highlights the severe and previously under-reported adverse impact of readily treatable tropical rickettsial illnesses, notably scrub typhus and murine typhus, on pregnancy outcomes, finding that more than one third of affected pregnancies resulted either in stillbirth or premature and/or low birth weight babies.
Scientists have discovered an ancient, deep canyon buried along the Yarlung Tsangpo River in south Tibet, north of the eastern end of the Himalayas. The geologists say that the ancient canyon -- thousands of feet deep in places -- effectively rules out a popular model used to explain how the massive and picturesque gorges of the Himalayas became so steep, so fast.
Doctors have long been mystified as to why HIV-1 rapidly sickens some individuals, while in others the virus has difficulties gaining a foothold. Now, a study of genetic variation in HIV-1 and in the cells it infects has uncovered a chink in HIV-1's armor that may, at least in part, explain the puzzling difference -- and potentially open the door to new treatments.
Archaeological findings pose questions about genetic resistance in humans to altitude sickness and genetic response in crop plants to flowering times and ultraviolet radiation tolerance. Archaeological discoveries from the 'roof of the world' on the Tibetan Plateau indicate that from 3,600 years ago, crop growing and the raising of livestock was taking place year-round at hitherto unprecedented altitudes.
China's second great wall, a vast seawall covering more than half of the country's mainland coastline, is a foundation for financial gain -- and also a dyke holding a swelling rush of ecological woes, experts report in a new article.
During the development of mammals, the growth and organization of digits are orchestrated by Hox genes, which are activated very early in precise regions of the embryo. These 'architect genes' are themselves regulated by a large piece of adjacent DNA. A new study reveals that this same DNA regulatory sequence also controls the architect genes during the development of the external genitals.
Found in South America and sub-Saharan Africa, each year yellow fever results in 200,000 new cases and kills 30,000 people. About 900 million people are at risk of contracting the disease. Now a research team has determined that the yellow fever virus, a hemorrhagic fever virus, replicates primarily in the liver; other organ failures that often follow in people with the disease are due to secondary effects.