Without any conflict with the second law of thermodynamics, heat can flow from a cooler but constantly heated body to another thermally connected and constantly hotter body. This anomalous heat transfer has been demonstrated in a two-phase liquid-vapor system composed of a Rayleigh–Bénard convection (RBC) cell filled one-half with normal liquid helium and one-half with […]
Maples rely on wind, upward currents, and gusts to spread their seeds over long distances that can reach several kilometers. Maple seeds are able to autorotate because their center of gravity, determined by the position of the nut, is located at the base of the wing-shaped seed. It has been observed that, despite their small […]
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Pear-shaped nuclei in some atoms may help explain antimatter Researchers have used a particle accelerator called REX-ISOLDE at CERN in Switzerland to discover an atom with pear-shaped nuclei. The discovery could lead scientists to extend the Standard Model in physics and help to explain why there is more matter than antimatter in the universe. LiveScience […]
Bees visit flowers to obtain nectar (a sugary liquid) and pollen (their source of fat and protein). During foraging trips, bees do not choose flowers at random. For example, as first pointed out by Aristotle, bees visit only one type of flower in each of their foraging trips. How do bees recognise flowers? Colour textures […]
Consider a set of distinct points in the plane, no three of them on the same line. Draw straight-line segments joining pairs of those points. This is called a geometric graph and here we are going to focus on the segments of such a graph. Every segment has two sides, defined by the line in […]
There are some science news that appear recursively in the media. Just to stick to my field of knowledge we could point to Mars’ water and habitability of extra solar planets. It is certainly great to have people reading about those topic, although some confusion seems to have settled down among public opinion. I am […]
Cryptography is, beyond any doubt, an important technology. Keeping the privacy of communications has many applications in modern societies. For instance, being able to send a message, as your credit card number, with the confidence that no one will understand it if it is intercepted, is a basic assumption for electronic transactions. Also, nowadays and […]
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Jamestown settlers turned to cannibalism to survive, bones show The scarred skull of a 14-year-old girl reveals that English settlers in Jamestown, Va., may have engaged in cannibalism to survive. A brutal winter in 1609 brought a food shortage, killing off 80% of the population. Marks on the girl’s skull and tibia are the first […]
At my workplace, we received recently a survey to measure our engagement at work. We were asked to evaluate different aspects of our daily job, such as the work atmosphere, productivity, performance…, and each question would accumulate points for our working team. For those items in which our team scored less, we were required to […]
Carbohydrates are molecules composed of carbon, oxygen and hydrogen. They are formed of at least three atoms of carbon. Monosaccharides are the simplest carbohydrates and they cannot be hydrolyzed to smaller carbohydrates. Among the monosccharides we find glucose or fructoses which are formed of six atoms of carbon or glyceraldehyde which is composed of three […]