Showing 20 articles starting at article 341

< Previous 20 articles        Next 20 articles >

Categories: Paleontology: Early Mammals and Birds, Physics: Acoustics and Ultrasound

Return to the site home page

     (via sciencedaily.com)     Original source 

The conditions under which early members of the genus Homo dispersed outside Africa were analysed on a broader scale, across Europe during the Early and Middle Pleistocene. The model is based on the comparison of functional trait distribution of large herbivorous mammals in sites with archaeological or fossil evidence of human presence and in sites, which lack evidence of human presence.

     (via sciencedaily.com) 

Researchers have conducted the first demonstration of a faster and more accurate way to calibrate certain kinds of microphones. The technique, which uses lasers to measure the velocity at which a microphone's diaphragm vibrates, performs well enough to overtake one of the main calibration methods used.

     (via sciencedaily.com) 

Bird dispersal movements are thought to depend on complex demographic and genetic factors. Researchers show that there may be a simpler explanation: bird dispersal distances depend on the morphology and flight efficiency of the wings. Bird populations and the capacity of species to move across the landscape can determine which species will thrive and which may become endangered.

     (via sciencedaily.com) 

The rise and fall of Earth's land surface over the last three million years shaped the evolution of birds and mammals, a new study has found, with new species evolving at higher rates where the land has risen most.

     (via sciencedaily.com) 

Researchers have developed three designs for compact speaker systems that control the direction of sound more efficiently than previous models. For each speaker, the scientists were able to manipulate the timing and strength of the outgoing sound waves. They combined multiple speakers together into an array and used the constructive and destructive interference of sound waves to their advantage.

     (via sciencedaily.com) 

While doctors have used low-intensity ultrasound as a medical imaging tool since the 1950s, experts are now using and extending models that help capture how high-intensity focused ultrasound (HIFU) can work on a cellular level.

     (via sciencedaily.com) 

With wind generation one of the fastest-growing renewable energy sectors in the world, experts are using machine learning and other signal processing techniques to characterize annoying noise features from wind farms. Two new publications from the ongoing Wind Farm Noise Study take another step towards improving wind turbine noise assessment methods, guidelines and wind turbine design to make wind energy more acceptable to surrounding communities.

     (via sciencedaily.com)     Original source 

Scientists have discovered three new species of ancient creatures from the dawn of modern mammals that hint at rapid evolution immediately after the mass extinction of the dinosaurs.

     (via sciencedaily.com) 

Prediction models based on clinical characteristics and imaging findings may help reduce the false-positive rate in women with dense breasts who undergo supplemental breast cancer screening with MRI, according to a new study.

     (via sciencedaily.com) 

A new study has revealed that over the last 20,000 to 50,000 years, birds have undergone a major extinction event, inflicted chiefly by humans, which caused the disappearance of about 10 to 20 percent of all avian species. According to the researchers, the vast majority of the extinct species shared several features: they were large, they lived on islands, and many of them were flightless.

     (via sciencedaily.com)     Original source 

A different kind of design for absorbing vibrations could help better soundproof walls and make vehicles more streamlined, a new study shows.

     (via sciencedaily.com) 

When we speak, we use our auditory and somatosensory systems to monitor the results of the movements of our tongue or lips. Since we cannot typically see our own faces and tongues while we speak, however, the potential role of visual feedback has remained less clear. Researchers explore how readily speakers will integrate visual information about their tongue movements during a speech motor learning task.

     (via sciencedaily.com) 

Research on a newly discovered bird fossil found that a unique brain shape may be why the ancestors of living birds survived the mass extinction that claimed all other known dinosaurs.

     (via sciencedaily.com) 

Researchers have demonstrated a low-cost technique for retrieving nanowires from electronic devices that have reached the end of their utility and then using those nanowires in new devices. The work is a step toward more sustainable electronics.

     (via sciencedaily.com) 

Engineers developed a soft, stretchy ultrasound patch that can be worn on the skin to monitor blood flow through vessels deep inside the body. Such a device can make it easier to detect cardiovascular problems, like blockages in the arteries that could lead to strokes or heart attacks.

     (via sciencedaily.com) 

Newly-hatched pterosaurs may have been able to fly but their flying abilities may have been different from adult pterosaurs, according to a new study. Researchers found that hatchling humerus bones were stronger than those of many adult pterosaurs, indicating that they would have been strong enough for flight.

     (via sciencedaily.com) 

New findings from zoologists working with birds in Southeast Asia are shining fresh light on the connections between animal behaviour, geology, and evolution - underlining that species can diversify surprisingly quickly under certain conditions. Sulawesi Babblers (Pellorneum celebense), shy birds that live in the undergrowth on Indonesian islands, have begun to diverge quite significantly despite being separated geographically for mere tens of thousands of years.

     (via sciencedaily.com)     Original source 

Engineers made a pneumatic RAM chip using microfluidic valves instead of electronic transistors. The valves remain sealed against a pressure differential even when disconnected from an air supply line, creating trapped pressure differentials that function as memories and maintain the states of a robot's actuators. Dense arrays of these valves can perform advanced operations and reduce the expensive, bulky, and power-consuming electronic hardware typically used to control pneumatic robots.

     (via sciencedaily.com) 

Researchers have found that the magnetic field of the MRI scanner decreased the BBB opening volume by 3.3-fold to 11.7-fold, depending on the strength of the magnetic field, in a mouse model.

     (via sciencedaily.com) 

Scientists have used a compound made from a starch derivative and baking soda to help convert mechanical to electrical energy. The approach is cost-effective and biocompatible, and can help charge low-energy electronics like calculators and watches.