Science & TechnologyS


Control Panel

Scientists Discover New Water Waves

Image
© Jean Rajchenbach, et al./American Physical SocietyThe even (left) and odd (right) standing solitary waves, whose motions can be seen in the video below.
By precisely shaking a container of shallow water, researchers have observed wave behavior that has never been seen before. In a new study, Jean Rajchenbach, Alphonse Leroux, and Didier Clamond of the University of Nice-Sophia Antipolis in Nice, France, have reported the observation of two new types of standing waves in water, one of which has never been observed before in any media.

In their study, which is published in a recent issue of Physical Review Letters, the scientists explain how they discovered the new waves. They confined water inside a Hele-Shaw cell, which is a container made of two parallel glass plates separated by a small gap. In this case, the plates were positioned vertically, like the two sides of an ant farm. The plates were 30 cm wide, and the gap between them was just 1.5 mm. The water inside was about 5 cm deep.

The researchers mounted the Hele-Shaw cell on a shaker, which vertically vibrated the cell and the water inside. While carefully controlling the vibration frequency and amplitude, they recorded the water surface deformation with a high-speed camera.

When the researchers slowly increased the oscillation amplitude, two-dimensional standing waves with large amplitudes began to form on the water's surface. As the researchers explained, these waves are called Faraday waves, which form on the surface of a vibrating fluid when the vibration frequency exceeds a certain value, and the surface becomes unstable.

Frog

Tortoise Populations Can Withstand Fires Every 30 Years

Image
© Andrés GiménezThe fire killed 100 percent of the spur-thighed tortoises (Testudo graeca) aged under four.
Populations of spur-thighed tortoises (Testudo graeca), a species classified as vulnerable and at risk of extinction, can withstand fires if outbreaks occur once every three decades or more. However, the youngest tortoises are more vulnerable, and disappear after each fire. These are the results of a study by Spanish researchers, who analysed the impact of a 2004 forest fire in the Sierra de la Carrasquilla mountains in Murcia (Spain) on these reptiles.

"Tortoises can withstand high temperatures, but this does not mean their shells are completely fire proof", Ana Sanz-Aguilar, lead author of the study, tells SINC. Currently a postdoctoral scholar at the Centre for Functional and Evolutionary Ecology in Montpellier, France, she collaborated with the Miguel Hernández University (UMH) and the Mediterranean Institute for Advanced Studies (IMEDEA-CSIC) for this research.

One such forest fire occurred on 1 August 2004 in the Sierra de la Carrasquilla mountains in Murcia, Spain, which incinerated a 250-hectare area that was home to a large population of these reptiles. The researchers have been studying the behaviour of more than 1,000 of the animals over the past decade.

The study, published in the journal Biological Conservation, shows that the tortoises' response to fire varied greatly according to their age, with the fire killing 100% of the animals aged under four and causing increased mortality rates of 62% in sub-adults (aged from 4 to 8) and 12% in adults (over 8 years of age).

Telescope

Stellar Eclipse Gives Glimpse of Exoplanet

Image
© Jason Rowe/NASA/Ames/Jaymie Matthews/UBCA rendering of the silhouette of 55 Cancri e transiting its parent star, compared to the Earth and Jupiter transiting our sun. Image:
A group of astronomers led by an MIT professor has spotted an exoplanetary eclipse of a star only 40 light years away - right around the corner, astronomically speaking - revealing a "super-Earth."

The far-out planet, named 55 Cancri e, is twice as big as Earth and nearly nine times more massive. It is most likely composed of rocky material, similar to Earth, supplemented with light elements such as water and hydrogen gas. Scientists estimate the planet's surface is much hotter than ours: close to 2,700 degrees Celsius.

Exoplanets - planets outside our own solar system - have captivated astronomers in recent years as interest in finding life on other Earth-like planets has intensified.

But Josh Winn, the Class of 1942 Career Development Assistant Professor of Physics at MIT, says exobiologists should probably not flock to 55 Cancri e looking for signs of life: The temperatures are just too high to sustain living organisms. But he suspects the exoplanet will attract the telescopes of many astronomers, mainly for reasons of visibility: 55 Cancri e is relatively close to Earth compared to other known exoplanets, and, as a result, the star around which the planet orbits appears roughly 100 times brighter than any other star with an eclipsing planet.

Telescope

Scientists Discover 10 New Planets

Image
© Shutterstock
A total of 10 new planets have been unearthed by an international team of scientists, and one of these is orbiting a star just a few tens of millions years old.

Using the CoRoT (Convection, Rotation and Transits) space telescope, operated by the French Space Agency (CNES), astrophysicists from the UK and France were able to see planets from outside our solar system, so-called 'exoplanets', when they were in transit, i.e. when they passed in front of their stars.

As well as the planet orbiting the unusually young star, the team also uncovered seven hot Jupiter-like planets, two Neptune-sized planets orbiting the same star, and a planet slightly smaller than Saturn.

Dr. Suzanne Aigrain from the Department of Physics at Oxford University in the United Kingdom said: 'Finding planets around young stars is particularly interesting because planets evolve very fast initially, before settling into a much steadier pattern of evolution. If we want to understand the conditions in which planets form, we need to catch them within the first few hundred million years. After that, the memory of the initial conditions is essentially lost. In the case of CoRoT-18 [the planet orbiting the young star], different ways of determining the age give different results, but it's possible that the star might be only a few tens of millions of years old. If this is confirmed, then we could learn a lot about the formation and early evolution of hot gas giant planets by comparing the size of CoRoT-18b to the predictions of theoretical models.'

Magnify

Scientists Studying Wasps Discover Being Social is Better for Fighting Disease

Image
© Paul Edward Duckett
In a paper release today, a group of scientists from Macquarie University studying the evolution of disease resistance in insects have found evidence that social species of wasps show significantly higher antimicrobial activity than solitary species.

The research, which was attempting to explain what allowed such complex societies to evolve, found that the origin of antimicrobial defenses in wasps is strongly linked to the species group size and social complexity.

According to one of the lead researchers Mr Stephen Hoggard, "The result provides evidence for the origin of antimicrobial defenses in wasps and increases our understanding of trends in disease resistance strategies in all social insects."

The findings suggest that wasps originally developed specialized antibiotic defenses to cope with living in the ground in solitary conditions but these then evolved and became much stronger to cope with disease risks associated with living in large groups.

These initial findings could have much further reaching applications. "Being able to understand what is driving the evolution of these antibiotic compounds may help scientists isolate naturally occurring antibiotics in the future and may eventually lead to the location of natural antibiotics for human use", say Hoggard.

Telescope

Neighbor Galaxy Caught Stealing Stars

Astronomers from the National Optical Astronomy Observatory (NOAO) and their collaborators have found that hundreds of the stars found in the Large Magellanic Cloud (LMC) were stolen from another nearby galaxy - the Small Magellanic Cloud (SMC). The Large and Small Magellanic Clouds are both neighbor galaxies to our Milky Way Galaxy and easily visible to the unaided eye from the southern hemisphere.

Image
© Karl Gordon/Margaret Meixner/AURA/NASAThe Milky Way’s near neighbor, the Large Magellanic Cloud (LMC), has accreted a smattering of stars from its smaller neighbor, the Small Magellanic Cloud (SMC). In this image, the LMC is shown as it appears in observations by the Spitzer Space Telescope at 3.6, 8.0, and 24 microns. Overlaid in red and blue, with colors representing the light of sight velocities (red = away, blue = towards) are the locations of stars whose origin has been traced to the SMC. These stars were discovered by a team led by NOAO astronomer Knut Olsen, through analysis of spectra obtained at the CTIO 4-m Blanco telescope.
By analyzing the spectra of 5900 giant and supergiant stars in the Large Magellanic Cloud galaxy, NOAO astronomers Knut Olsen and Bob Blum, and their collaborators Dennis Zaritsky (University of Arizona), and Martha Boyer and Karl Gordon (Space Telescope Science Institute) found that over 5% of the stars they observed in the LMC are rotating counter to the direction of the majority of LMC stars, or perhaps in a plane that is greatly inclined to the rotation of the LMC. An ambiguity remains in the result, because the astronomers were only able to measure the projection of the stellar velocities into the line of sight, and not their full velocity vectors. In either case, these peculiar orbits indicate that these stars probably did not form from the rotating and collapsing cloud of gas that formed the LMC, a galaxy located about 160,000 light years away.

Further examination of these counter-rotating stars revealed another anomaly. The chemical composition of these stars is different. They have fewer heavy elements such as iron and calcium than typical stars in the Large Magellanic Cloud. However, their composition closely matches that of stars in another nearby galaxy, the Small Magellanic Cloud, whose stars are also depleted in these "metals".

Magic Wand

US: Explorers discover 3 billion-year-old life forms off the coast of Michigan

In mysterious sinkholes beneath the waters of Lake Huron, scientists have been exploring strange pockets of life that shouldn't exist on present-day Earth. The microbes researchers have found would have been perfectly comfortable on the Earth of 3 billion years ago, before we had oxygen in the atmosphere.

Image
© Grand Valley State University
How did the bottom of Lake Huron get riddled with sinkholes that time forgot? Find out, and see a video of life that hasn't existed for billions of years.

The sinkholes at the bottom of the lake are pockets of de-oxygenated water that have pooled beneath the fresh waters above. So all the creatures who live in the sinkholes might have evolved at a time on Earth when no oxygen was available. In a recent Earth magazine article about the ongoing exploration of these sinkholes, first discovered a little over a decade ago, Lindsey Doermann writes:
These pockets of water teem with microbial life similar to that found around deep ocean hydrothermal vents or beneath ice-covered Antarctic lakes, not the kinds of microorganisms normally found in our own backyards . . . Before long, the true importance of these oddities became apparent: "These ecosystems in Lake Huron are analogs of the Proterozoic," says Bopi Biddanda, a microbial ecologist at Grand Valley State University in Michigan and one of the leaders of the sinkhole science team. "They could be windows into communities that existed 3 billion years ago."

Info

Lingering Lies: The Persistent Influence of Misinformation

Lies
© Scientific American

After people realize the facts have been fudged, they do their best to set the record straight: judges tell juries to forget misleading testimony; newspapers publish errata. But even explicit warnings to ignore misinformation cannot erase the damage done, according to a new study from the University of Western Australia.

Psychologists asked college stu­dents to read an account of an ac­cident involving a busload of elderly passengers. The students were then told that, actually, those on the bus were not elderly. For some students, the information ended there. Others were told the bus had in fact been transporting a college hockey team. And still others were warned about what psychologists call the continued influence of misinformation - that people tend to have a hard time ig­noring what they first heard, even if they know it is wrong - and that they should be extra vigilant about getting the story straight.

Students who had been warned about misinformation or given the alternative story were less likely than control subjects to make inferences using the old information later - but they still erred sometimes, agreeing with statements such as "the pas­sengers found it difficult to exit the bus because they were frail."

Info

Manufacturers Turn to 3-D Printing

3D Printing
© Materialise Future factory: Machines stand ready to produce products through additive manufacturing techniques.

Hobbyists may have provided the first demand for 3-D printing, but while DIY enthusiasts were creating online communities to make their own action figures and knickknacks out of plastic, industrial manufacturers were discovering how new materials and techniques in 3-D printing could change the way they make commercial products.

A 3-D printer deposits a string of hot plastic, lets it cool, and moves on to the next plane to build a three-dimensional object slice by slice. Using the same principles of layering, additive manufacturing can build objects out of metals, plastics, and ceramics in geometric shapes that are impossible to achieve with other manufacturing techniques. Because the design is digital, businesses can order the resulting products from any available 3-D printer.

This May, General Electric announced that it would "intensify focus" on additive manufacturing to develop a variety of products, from aircraft engine components to parts for ultrasound machines. Other large manufacturers have used the technique to make industrial scanners, furniture, and medical equipment.

Blackbox

Eqypt's Antiquities Boss Zahi Hawass Is Sacked?

Image
© UnknownZahi Hawass
After nearly a decade as chief of Egypt's antiquities, Zahi Hawass is now out of a job.

The 64-year-old archaeologist was fired yesterday by Prime Minister Essam Sharaf as part of a wider shakeup of his cabinet. Protestors at Cairo's Tahrir Square had been calling for his ouster as minister of antiquities for months. "All the devils united against me," Hawass told Science Insider.

The country's most prominent figure in archaeology, Hawass was instrumental in sending large blockbuster exhibits abroad, creating a host of new museums and secure storerooms, and pressuring foreign excavators to publish their finds more quickly. But he was also criticized for his portrayal on American television of archaeology as treasure hunting, excoriated for his dictatorial management style, and accused of shoddy research in carrying out his own digs. Sharaf is said to have appointed Abdel-Fattah El-Banna as Hawass' replacement, but there are reports that protestors have rejected that nomination, and that Sharaf might reverse his decision and name someone else.