Bacteria in a drop of water spontaneously form a bi-directional vortex, with bacteria near the center of the drop swimming in the opposite direction of bacteria swimming near the edge. New computer simulations, confirmed by a novel experiment, explain how that vortex comes to be.
PROVIDENCE, R.I. [Brown University] — When a bunch of B. subtilis bacteria are confined within a droplet of water, a very strange thing happens. The chaotic motion of all those individual swimmers spontaneously organizes into a swirling vortex, with bacteria on the outer edge of the droplet moving in one direction while those on the inside move the opposite direction. (more…)
Derzeit verrichten im Rahmen der BRITE-Constellation vier Nanosatelliten ihren Dienst im Weltraum für AstrophysikerInnen in Österreich, Kanada und Polen. Die beiden Nanosatelliten UniBRITE und BRITE-Austria kommen aus Österreich. Die im Februar 2013 gestartete Mission gerät immer wieder in erhebliche Gefahr: Der Grund dafür ist Weltraumschrott, mit dem die Satelliten zusammenstoßen könnten. Aktuell erreichte die Astrophysiker der Universität Wien die Nachricht, dass ein Schrottteil eines chinesischen Wettersatelliten morgen Dienstag, 5. August 2014, UniBRITE, dem Satelliten der Universität Wien, auf etwa neun Meter nahe kommen wird. Das gesamte Forschungsteam hofft nun, dass es zu keinem Zusammenstoß kommen wird.
Vier Nanosatelliten verrichten bereits ihren Dienst im Weltraum im Rahmen astrophysikalischer Forschungsprojekte in Österreich, Kanada und Polen. UniBRITE, der Satellit der Universität Wien, und BRITE-Austria, jener der Technischen Universität Graz, wurden am 25. Februar 2013 von Indien aus gestartet – Österreich war damit erstmals Satelliten-Startland. Am 21. November 2013 folgte der erste polnische Satellit, BRITE-Lem, mit einem Start von Russland. Am 13. Juni 2014 wurden zwei baugleiche kanadische BRITE-Satelliten (BRITE-Toronto und BRITE-Montreal) ebenfalls von Russland aus auf ihre Mission geschickt. Der Start des zweiten polnischen Satelliten, BRITE-Heweliusz, ist für 19. August 2014 von China aus geplant. Das wird den Aufbau dieses Netzwerks von Kleinsatelliten mit dem Ziel der Präzisionsphotometrie von hellen Sternen im roten und blauen Farbbereich vorläufig zu einem Abschluss bringen. (more…)
Thanks to NASA’s Kepler and Spitzer Space Telescopes, scientists have made the most precise measurement ever of the radius of a planet outside our solar system. The size of the exoplanet, dubbed Kepler-93b, is now known to an uncertainty of just 74 miles (119 kilometers) on either side of the planetary body.
The findings confirm Kepler-93b as a “super-Earth” that is about one-and-a-half times the size of our planet. Although super-Earths are common in the galaxy, none exist in our solar system. Exoplanets like Kepler-93b are therefore our only laboratories to study this major class of planet. (more…)
University of Utah researchers find that multiple silent mutations greatly impact protein translation
So-called silent DNA mutations earned their title because, according to the fundamental rules of biology, they should be inconsequential. Reported on June 5 in PLOS Genetics online, University of Utah researchers experimentally proved there are frequent exceptions to the rule. The work was conducted in the bacteria, Salmonella enterica, used to study basic biological mechanisms that are often conserved in humans. (more…)
While African wildlife often run afoul of ranchers and pastoralists securing food and water resources for their animals, the interests of fauna and farmer might finally be unified by the “Sodom apple,” a toxic invasive plant that has overrun vast swaths of East African savanna and pastureland.
Should the ominous reference to the smitten biblical city be unclear, the Sodom apple, or Solanum campylacanthum, is a wicked plant. Not a true apple, this relative of the eggplant smothers native grasses with its thorny stalks, while its striking yellow fruit provides a deadly temptation to sheep and cattle. (more…)
ANN ARBOR — In work that unmasks some of the magic behind memristors and “resistive random access memory,” or RRAM—cutting-edge computer components that combine logic and memory functions—researchers have shown that the metal particles in memristors don’t stay put as previously thought.
The findings have broad implications for the semiconductor industry and beyond. They show, for the first time, exactly how some memristors remember. (more…)
A new study of sharks that lived in warm Arctic waters millions of years ago suggests that some shark species could handle the falling Arctic salinity that may come with rising temperatures.
The Arctic today is best known for its tundra and polar bear population, but roughly 38 to 53 million years ago during the Eocene epoch, the Arctic was like a huge temperate forest with brackish water, home to a variety of animal life, including ancestors of tapirs, hippo-like creatures, crocodiles and giant tortoises. Much of what is known about the region during this period comes from well-documented terrestrial deposits. Marine records have been harder to come by. (more…)
Researchers at UCLA have created a nanoscale magnetic component for computer memory chips that could significantly improve their energy efficiency and scalability.(more…)
