Science News
New way to filter light: May provide first directional selectivity for light waves
Massachusetts Institute of Technology
Light waves can be defined by three fundamental characteristics: their color (or wavelength), polarization, and direction. While it has long been possible to selectively filter light according to its color or polarization, selectivity based on the direction of propagation has remained elusive.
But now, for the first time, MIT researchers have produced a system that allows light of any color to pass through only if it is coming from one specific angle; the technique reflects all light coming from other directions. This new approach could ultimately lead to advances in solar photovoltaics, detectors for telescopes and microscopes, and privacy filters for display screens.
The work is described in a paper appearing this week in the journal Science, written by MIT graduate student Yichen Shen, professor of physics Marin Soljačić, and four others. "We are excited about this," Soljačić says, "because it is a very fundamental building block in our ability to control light."
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Crows Understand Water Displacement Proving Aesop’s Fable
Brett Smith for redOrbit.com
In a well-known Aesop’s fable, a crow comes across a pitcher with a small, out-of-reach amount of water in the bottom. To get a drink, the crow drops stones in the pitcher until the water level rises enough for the bird to reach it with its beak.
While the point to the fable may be to teach the virtue of ingenuity, a team of scientists from New Zealand and the United Kingdom wanted to see if New Caledonian crows understood the idea behind displacing water with objects to receive a reward.
While previous research has shown that these crows are capable of solving this problem, the study team said they wanted to see if New Caledonian crows could demonstrate an ability to understand the concept of volume displacement – such as the fact that solid objects displace more water when they sink in water than hollow objects.
After a brief training period, the crows were tested in six different tasks that each had different tweaks to see if the birds did in fact understand the concept of volume displacement. The crows were able to complete 4 of 6 tasks, such as dropping stones into a water tube to reach a prize instead of dropping stones into a sand-filled tube. Other successful tests included dropping sinking objects rather than floating objects, choosing solid objects over hollow objects, and dropping objects into a tube with a high water level as opposed to a low one.
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Technology News
How Vintage Tech Helped Us Track the Missing Malaysia Airlines Jet
By Adam Mann
The saga of MH370, the Malaysian Airlines flight missing for more than two weeks, seems to be entering its final chapter. Earlier this week, engineers developed a method to estimate the plane’s trajectory, and debris appear to have been spotted in satellite images.
While the technique used to track the flight path has been called “groundbreaking,” it actually rests on some fairly old-fashioned physics. In fact, the basic method has been used to conduct satellite search and rescue operations for more than 30 years, predating our always-connected, GPS-enabled world.
Here’s how it worked in the case of MH370. For whatever reason, the Malaysian Airlines jet was unable to communicate during its final hours. But it continued to send out a signal to a satellite run by a company called Inmarsat, which provides communication for planes and ships and is one of the biggest satellite operators in the world. At regular intervals, the plane and satellite would try to establish contact by pinging one another, generating a handshake signal that basically said, “I’m here, can you talk?”
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Roku’s new streaming stick makes nearly any TV a smart TV
By Hayley Tsukayama
It's easier than ever to make your plain, old television into a smart TV, and Roku's new streaming stick has cleverly boiled down the best of the company's set-top boxes into something that's roughly the size of your thumb.
It's a big step for Roku, which has previously released set-top boxes and a streaming stick that only worked with "Roku Ready" televisions. Now, like Google's Chromecast, the Roku Streaming Stick only requires your television's HDMI port -- and a nearby USB port or outlet for power -- to bring you content from video providers such as Netflix, Hulu Plus and Amazon Instant Video. (Amazon.com chief executive Jeffrey Bezos is the owner of The Washington Post.) You can also stream content to your television screen by way of your phone's YouTube app, as you can with Google's device.
Unlike Google's Chromecast, however, the Roku Streaming Stick also has access to the hundreds of free and paid channels that Roku has in its stable including PBS, MGo, Vudu, and ESPN, giving users a much richer selection of content on hand. The device also lets you stream your own personal movies, music and photos to the television by way of a Roku smartphone app. The app also doubles as a digital remote -- something that's particularly useful when you're entering search terms or registration information and have the option of a touchscreen keyboard.
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Environmental News
Coal plant closure in China led to improvements in children's health
Columbia University's Mailman School of Public Health
Decreased exposure to air pollution in utero is linked with improved childhood developmental scores and higher levels of brain-derived neurotrophic factor (BDNF), a key protein for brain development, according to a study looking at the closure of a coal-burning power plant in China led by researchers at the Columbia Center for Children's Environmental Health at the Mailman School of Public Health.
The study is the first to assess BDNF and cognitive development with respect to prenatal exposure to polycyclic aromatic hydrocarbons (PAH), a component of air pollution commonly emitted from coal burning. Results appear online in the journal PLOS ONE.
The 2004 closure of a coal-burning power plant in Tongliang, China provided the opportunity to investigate the benefits to development and the impacts on BDNF associated with decreased levels of exposure to PAH. This study has linked decreases in air pollution with decreased levels of PAH-DNA adducts in cord blood, a biological marker of exposure, and reported an association between PAH exposure and adverse developmental outcomes in children born before the plant closure. Currently, coal-fired power plants produce more than 70% of China's electricity.
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This edible water blob could replace plastic bottles
The Ooho 'water bottle' is a gelatinous blob that allows you to have your bottled water without the plastic, and eat it too.
By: Bryan Nelson
What's one solution to the growing problem of plastic water bottle waste? A trio of Spanish design students think they have the answer, and it involves creating a 'water bottle' that you can eat, reports Co.Exist.
Designers Rodrigo García González, Guillaume Couche and Pierre Paslier call their creation "Ooho," a gelatinous blob which is actually a membrane that encapsulates water like a bladder. When you're thirsty, just puncture the membrane and drink. Or, if you also have an appetite, just pop a bite-sized Ooho in your mouth and chomp down for a burst of hydration. The gooey membrane, made from brown algae and calcium chloride, is edible, hygienic and biodegradable.
The Ooho globule is formed through a process called "spherification," a methodology first pioneered in 1946 and still utilized by some chefs in modern cuisine. Water is frozen into ice before being encapsulated to ease the process and prevent the water from mixing with the membrane ingredients. The bag-like containers are also incredibly cheap-- each one costs just two cents to make, and they could even be concocted at home.
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Medical News
Scientists publish 'navigation maps' for human genome
By Kate Kelland
(Reuters) - A large international team of scientists has built the clearest picture yet of how human genes are regulated in the vast array of cell types in the body - work that should help researchers target genes linked to disease.
In two major studies published in the journal Nature, the consortium mapped how a network of switches, built into human DNA, controls where and when genes are turned on and off.
The three-year long project, called FANTOM5 and led by the RIKEN Center for Life Science Technologies in Japan, involved more than 250 scientists across 20 countries and regions.
"Humans are complex multicellular organisms composed of at least 400 distinct cell types. This beautiful diversity of cell types allow us to see, think, hear, move and fight infection - yet all of this is encoded in the same genome," said Alistair Forrest, scientific coordinator of FANTOM5.
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Consistent blood pressure control may cut rate of second stroke in half
American Heart Association
Stroke survivors who consistently control their blood pressure may reduce the likelihood of a second stroke by more than half, according to new research in the American Heart Association journal Stroke.
For the study, researchers analyzed the results from the Vitamin Intervention for Stroke Prevention (VISP) trial, which enrolled 3,680 ischemic stroke patients ages 35 and older in 1996-2003. Ischemic strokes are caused by a clot or other blockage in a blood vessel supplying the brain. Participants had been tested for several risk factors, including blood pressure levels at baseline, a month after the start of the study, at six months and every six months thereafter up to 24 months.
Researchers determined results after controlling for age, sex and prior history of stroke, heart disease and other factors. Blood pressure was considered "controlled" at 140 mmHg over 90 mmHg or lower.
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Space News
First ring system around asteroid: Chariklo found to have two rings
European Southern Observatory - ESO
Observations at many sites in South America, including ESO's La Silla Observatory, have made the surprise discovery that the remote asteroid Chariklo is surrounded by two dense and narrow rings. This is the smallest object by far found to have rings and only the fifth body in the Solar System -- after the much larger planets Jupiter, Saturn, Uranus and Neptune -- to have this feature. The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris. The new results are published online in the journal Nature on 26 March 2014.
The rings of Saturn are one of the most spectacular sights in the sky, and less prominent rings have also been found around the other giant planets. Despite many careful searches, no rings had been found around smaller objects orbiting the Sun in the Solar System. Now observations of the distant minor planet [1] (10199) Chariklo [2] as it passed in front of a star have shown that this object too is surrounded by two fine rings.
"We weren't looking for a ring and didn't think small bodies like Chariklo had them at all, so the discovery -- and the amazing amountof detail we saw in the system -- came as a complete surprise!" says Felipe Braga-Ribas (Observatório Nacional/MCTI, Rio de Janeiro, Brazil) who planned the observation campaign and is lead author on the new paper.
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Dark energy hides behind phantom fields
Plataforma SINC
Quintessence and phantom fields, two hypotheses formulated using data from satellites, such as Planck and WMAP, are among the many theories that try to explain the nature of dark energy. Now researchers from Barcelona and Athens suggest that both possibilities are only a mirage in the observations and it is the quantum vacuum which could be behind this energy that moves our universe.
Cosmologists believe that some three quarters of the universe are made up of a mysterious dark energy which would explain its accelerated expansion. The truth is that they do not know what it could be, therefore they put forward possible solutions.
One is the existence of quintessence, an invisible gravitating agent that instead of attracting, repels and accelerates the expansion of the cosmos. From the Classical World until the Middle Ages, this term has referred to the ether or fifth element of nature, together with earth, fire, water and air.
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Odd News
Toilet Tech Fair Tackles Global Sanitation Woes
by KATY DAIGLE, AP Environment Writer
New Delhi (AP) — Who would have expected a toilet to one day filter water, charge a cellphone or create charcoal to combat climate change?
These are lofty ambitions beyond what most of the world's 2.5 billion people with no access to modern sanitation would expect. Yet, scientists and toilet innovators around the world say these are exactly the sort of goals needed to improve global public health amid challenges such as poverty, water scarcity and urban growth.
Scientists who accepted the Bill & Melinda Gates Foundation's challenge to reinvent the toilet showcased their inventions in the Indian capital Saturday. The primary goal: to sanitize waste, use minimal water or electricity, and produce a usable product at low cost.
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