'Growth Spurt' from a Newborn Protostar

Using data from orbiting observatories, including NASA's Spitzer Space Telescope, and from ground-based facilities, an international team of astronomers has discovered an outburst from a star thought to be in the earliest phase of its development. The eruption, scientists say, reveals a sudden accumulation of gas and dust by an exceptionally young star, or protostar, known as HOPS 383.

Stars form within collapsing fragments of cold gas clouds. As the cloud contracts under its own gravity, its central region becomes denser and hotter. By the end of this process, the collapsing fragment has transformed into a hot central protostar surrounded by a dusty disk roughly equal in mass, embedded in a dense envelope of gas and dust. Astronomers call this a "Class 0" protostar.

"HOPS 383 is the first outburst we've ever seen from a Class 0 object, and it appears to be the youngest protostellar eruption ever recorded," said William Fischer, a NASA Postdoctoral Program Fellow at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

The Class 0 phase is short-lived, lasting roughly 150,000 years, and is considered the earliest developmental stage for stars like the sun.

A protostar has not yet developed the energy-generating capabilities of a sun-like star, which fuses hydrogen into helium in its core. Instead, a protostar shines from the heat energy released by its contraction and by the accumulation of material from the disk of gas and dust surrounding it. The disk may one day develop asteroids, comets and planets.

Because these infant suns are thickly swaddled in gas and dust, their visible light cannot escape. But the light warms dust around the protostar, which reradiates the energy in the form of heat detectable by infrared-sensitive instruments on ground-based telescopes and orbiting satellites.

HOPS 383 is located near NGC 1977, a nebula in the constellation Orion, and is a part of its sprawling star-formation complex. Located about 1,400 light-years from Earth, the region constitutes the most active nearby "star factory" and hosts a treasure trove of young stellar objects still embedded in their natal clouds.

A team led by Thomas Megeath at the University of Toledo in Ohio used Spitzer to identify more than 300 protostars in the Orion complex. A follow-on project using the European Space Agency's Herschel Space Observatory, called the Herschel Orion Protostar Survey (HOPS), studied many of these objects in greater detail. NASA's Jet Propulsion Laboratory in Pasadena, California, manages Spitzer and, while Herschel was still active, managed the U.S. portion of that mission as well.

The eruption of HOPS 383 was first recognized in 2014 by astronomer Emily Safron shortly after her graduation from the University of Toledo. Under the supervision of Megeath and Fischer, she had just completed her senior thesis comparing the decade-old Spitzer Orion survey with 2010 observations from NASA's Wide-field Infrared Survey Explorer (WISE) satellite, which was also managed by JPL. Using software to analyze the data, Safron had already run through it several times without finding anything new. But with her thesis completed and graduation behind her, she decided to take the extra time to compare images of the "funny objects" by eye.

That's when she noticed HOPS 383's dramatic change. "This beautiful outburst was lurking in our sample the whole time," Safron said.

Safron's catalog of observations included Spitzer data at wavelengths of 3.6, 4.5 and 24 microns and WISE data at 3.4, 4.6 and 22 microns. HOPS 383 is so deeply enshrouded in dust that it wasn't seen at all before the outburst at the shortest Spitzer wavelength, and an oversight in a version of the catalog produced before Safron's involvement masked the increase at the longest wavelengths. As a result, her software saw a rise in brightness in only one wavelength out of three, which failed to meet her criteria for the changes she was hoping to find.

Once they realized what had happened, Safron, Fischer and their colleagues gathered additional Spitzer data, Herschel observations, and images from ground-based infrared telescopes at the Kitt Peak National Observatory in Arizona and the Atacama Pathfinder Experiment in northern Chile. Their findings were published in the Feb. 10 edition of The Astrophysical Journal.

The first hint of brightening appears in Spitzer data beginning in 2006. By 2008, they write, HOPS 383's brightness at a wavelength of 24 microns had increased by 35 times. According to the most recent data available, from 2012, the eruption shows no sign of abating.

"An outburst lasting this long rules out many possibilities, and we think HOPS 383 is best explained by a sudden increase in the amount of gas the protostar is accreting from the disk around it," explained Fischer.

Scientists suspect that instabilities in the disk lead to episodes where large quantities of material flow onto the central protostar. The star develops an extreme hot spot at the impact point, which in turn heats up the disk, and both brighten dramatically.

The team continues to monitor HOPS 383 and has proposed new observations using NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA), the world's largest flying telescope.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

For more information about Spitzer, visit: http://www.nasa.gov/spitzer

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NASA’s research shows threat to iceberg

Researchers at the University of Texas at Austin, NASA and other research organizations have discovered two seafloor troughs that could allow warm ocean water to reach the base of Totten Glacier, East Antarctica's largest and most rapidly thinning glacier. The discovery likely explains the glacier's extreme thinning and raises concern about its impact on sea level rise.

The result, published in the journal Nature Geoscience today, March 16, has global implications because the ice flowing through Totten Glacier alone is equivalent to the entire volume of the more widely studied West Antarctic Ice Sheet. If Totten Glacier were to collapse completely, global sea levels would rise by at least 11 feet (3.3 meters). As in the West Antarctic Ice Sheet, complete collapse of Totten Glacier may take centuries, although the timing of retreat in both places is the subject of intensive research.

East Antarctica has appeared to be stable compared with the rapidly melting western side of the continent. The new finding shows that "Totten Glacier and the East Antarctic Ice Sheet are a much more interesting and dynamic part of the sea level rise story than we'd previously thought," said co-author Dustin Schroeder, a scientist at NASA's Jet Propulsion Laboratory, Pasadena, California. Schroeder helped analyze data from an ice-penetrating radar to demonstrate that ocean water could access the glacier through the newfound troughs.

In some areas of the ocean surrounding Antarctica, warm water can be found below cooler water because it is saltier, and therefore heavier, than the shallower water. Seafloor valleys that connect this deep warm water to the coast can especially compromise glaciers, but this process had previously been seen only under the West Antarctic Ice Sheet. Deep warm water had been observed seaward of Totten Glacier, but there was no evidence that it could compromise coastal ice.

The newly discovered troughs are deep enough to give the deep warm water access to the huge cavity under the glacier. The deeper of the two troughs extends from the ocean to the underside of Totten Glacier in an area not previously known to be floating.

The data for this study were gathered as part of the International Collaboration for Exploration of the Cryosphere through Airborne Profiling (ICECAP) project, which, together with the East Antarctic component of NASA's Operation IceBridge mission, made the first comprehensive survey of the Totten Glacier Ice Shelf and nearby regions between 2008 and 2012. Other coauthors of the study come from research organizations and universities in Australia, France and England.

The paper is available at
http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2388.html

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Space Technology will help in kidney dialysis

The color represented speed of blood

A team of researchers in the United Kingdom has found a way to redesign an artificial connection between an artery and vein, known as an Arterio-Venous Fistulae, which surgeons form in the arms of people with end-stage renal disease so that those patients can receive routine dialysis, filtering their blood and keeping them alive after their kidneys fail.
Related Articles Dialysis Kidney transplantationTensile strength
Constructal theory Sports medicine Heart failure The new design, described in the journal Physics of Fluids, from AIP Publishing, may decrease the likelihood of blockages in Arterio-Venous Fistulae, which is a major complication of dialysis.
While the AVF would have to prove effective in clinical trials before they could be deemed a success, the researchers are enthusiastic about their approach, which used software from the aerospace industry to design the novel configurations.
"At the moment, the process of creating an Arterio-Venous Fistulae for dialysis is rather 'one-size-fits-all'," said Peter Vincent, a senior lecturer and EPSRC early career fellow in the Department of Aeronautics at Imperial College London. "Our ultimate aim is to use computational simulation tools to design tailored, patient-specific Arterio-Venous Fistulae configurations that won't block and fail."
Dialysis and Chronic Kidney Disease
Dialysis is a life-saving treatment for end-stage renal disease -- the last stage of chronic kidney disease -- a serious and often fatal health condition in which a person's kidneys become damaged and can no longer filter blood as effectively as healthy kidneys. As a result, wastes from the blood remain within the body and often lead to other health problems such as cardiovascular disease, anemia and bone disease.
Chronic kidney disease is a global health challenge. For perspective, in the United States alone, the Centers for Disease Control and Prevention estimates that more than 20 million adults -- more than 10 percent of the U.S. adult population -- may have the disease, although many are undiagnosed. Kidney disease is now the 9th leading cause of death in the U.S.
Once a person's kidney's fail, they require either a kidney transplant or regular treatment via a dialysis machine to keep filtering the blood like a kidney. Transplant surgeries often have very good outcomes, but the procedures are limited by the availability of donated kidneys, and only a few thousand become available every year in the United States, while tens of thousands of people are on the waiting list for a kidney transplant. People often wait for a new kidney transplant for years, having to undergo periodic dialysis the entire time.
One problem that arises with dialysis is that the connections made between the body and a dialysis machine via an Arterio-Venous Fistulae frequently become blocked and fail shortly after they are created -- leading to unfavorable clinical outcomes and a significant additional cost burden for healthcare systems worldwide.
So an interdisciplinary team of U.K. researchers -- including members from aeronautics, bioengineering, computational engineering, medical imaging and clinical medicine -- from Imperial College London, Imperial College Renal and Transplant Centre at Hammersmith Hospital, and St. Mary's Hospital set out to design an Arterio-Venous Fistulae with reduced failure rates.
Design Based on Aerospace Software
To do this, the researchers first needed to gain a better understanding of how arterial curvature affects blood flow and oxygen transport patterns within Arterio-Venous Fistula.
Blood flow patterns within AVF are "inherently 'un-natural,' and it's thought that these unnatural flow patterns lead to their ultimate failure," explained Vincent.
By using computational simulation software originally developed for the aerospace sector, the team is able to simulate and predict flow patterns in various Arterio-Venous Fistula configurations. "This allows us to design Arterio-Venous Fistula with much mor

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How brain transforms with aging: a report

Typical cognitive aging may be defined as age-associated changes in cognitive performance in individuals free of dementia. To assess brain imaging findings associated with typical aging, the full adult age spectrum should be included, according to the study background.
Clifford R. Jack, Jr., M.D., of the Mayo Clinic and Foundation, Rochester, Minn., and coauthors compared
 age, sex and APOE ɛ4 effects on memory, brain structure (as measured by adjusted hippocampal volume, HVa) and amyloid [brain plaques associated with Alzheimer disease] positron emission tomography (PET) in 1,246 cognitively normal individuals between the ages of 30 and 95.
The authors found:
Overall memory worsened from age 30 through the 90s.
HVa worsened gradually from age 30 to the mid-60s and more steeply after that with advancing age.
Median amyloid accumulation seen on PET scans was low until age 70 but increased after that.
Memory was worse in men than women overall, especially after 40.
The HVa was lower in men than women overall, especially after 60.
For both males and females, memory performance and HVa were not different by APOE ɛ4 carrier status at any age.
From age 70 onward, APOE ɛ4 carriers had greater median amyloid accumulation seen on PET scans than noncarriers.
The ages at which 10 percent of the population was "amyloid PET positive" were 57 years for APOE ɛ4 carriers and 64 years for noncarriers. Amyloid PET positive indicates individuals are accumulating amyloid in their brain as seen on PET scans and, while they may be asymptomatic, they are at risk for Alzheimer disease.
"We believe that this study of typical aging reveals interesting sex and APOE ɛ4 effects on age-related trends in brain structure, function and β-amyloidosis [buildup of plaque deposits in the brain]. To date, these effects have not been widely appreciated. Our findings are consistent with a model of late-onset AD [Alzheimer disease] in which β-amyloidosis arises later in life on a background of preexisting structural and cognitive decline that is associated with aging and not with β-amyloid deposits," the study concludes.
Editorial: A Call for New Thoughts on What Might Influence Human Brain Aging
In a related editorial, Charles DeCarli, M.D., of the University of California at Davis, Sacramento, writes: "In their article, Jack et al present new information that challenges the notion that amyloid accumulation explains memory performance across the entire age range. Importantly, this work does not only address the likely highly significant impact of cerebral amyloid accumulation on dementia risk, but also extends current knowledge relating to the impact of the aging process across the spectrum of ages 30 to 95 years to brain structure, amyloid accumulation and memory performance among cognitively normal individuals."
"Understanding the basic biology of these early processes are likely to substantially inform us about ways in which we can maintain cognitive health and optimize resistance to late-life dementia. However, such work requires the necessary motivation found by seminal work, such as that of Jack et al, which tell us where and when to investigate these processes. Establishing what is normal creates avenues for new research, increasing the likelihood of discovering novel therapeutics for late-life disease states, which is a laudable goal indeed," the editorial concludes.

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Tyre that converts Heat into Work

The world demands Energy, and energy from everything that is what our future is all about and the one who can produce Energy will be at top of chart. Something similar happened this week in Geneva International Auto Show where tyre manufacturer Goodyear introduced a new concept of energy generation from the tyres.

A traditional car gets its power from engine which in turn rotates the wheels but a new concept tyre introduced by Goodyear named BHO3 which would use all the heat energy which it gets from various sources like sunlight, friction to convert it into useful or mechanical work,  which could be considered as a tyre full of surprises.

Goodyear is interested in producing energy directly from the tires, harvesting their heat energy with its BHO3 concept tire. According to Goodyear, while the car is sitting idle, the BHO3 tires would start to warm as sunlight hits the tires and the ground beneath. (The tire will be given an ultra black coat for maximum absorption of light and heat.) The heat would be transferred to the car through thermoelectric materials just under the tire’s surface that can generate voltage as the material flexes in response to temperature changes.


And when the car is moving the friction force will come into action which would result in the increment of the temperature of the tires and the heat can be collected through the sensors. “These concept tires reimagine the role that tires may play in the future,” Joe Zekoski, Goodyear’s senior vice president and chief technical officer, said in a statement.

The company only explained about the tyres bit not about the types of materials used for collecting heat, or how it would convert it into work or how it would maintain the cooling off the superheated tyre, but one thing is sure if the tyre comes into action it could eliminate our need for gasoline

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Pen with Bio-Ink: the future of sensors

Ballpoint pens loaded with sensor-laden inks could eliminate finger pricks for diabetics, and help them test their blood glucose levels simply by drawing cartoons - or just a few dots - on their skin.

The innovative new ink could also be used to test for pollutants in the environment by drawing on leaves or on buildings' surfaces, and could help soldiers search for explosives and chemical weapons, the developers say.

The team of engineers from the University of California, San Diego, who developed the ink, used it to fill up regular, off-the-shelf ballpoint pens. The aim was to enable a new type of do-it-yourself sensor with rapid diagnostic capabilities for people with diabetes.

The ink is made from the enzymes glucose oxidase, which responds to sugar in the blood, and tyrosinase, which can help detect common pollutants known as phenols. These compounds are found in cosmetics and can be toxic at high enough concentrations.  

Charles Choi explains for IEEE Spectrum what else was needed to make the inks operate like on-demand sensors: “To make these bio-inks serve as electrodes, they added electrically conductive graphite powder. They also added: chitosan, a clotting agent used in bandages, to help the ink stick to surfaces; xylitol, a sugar substitute, to help stabilize the enzymes during chemical reactions; and biocompatible polyethylene glycol, which is used in several drug delivery applications, to help bind all these ingredients together.”

The team has described its "enzymatic ink" and do-it-yourself sensor in the journal Advanced Healthcare Materials.

Using their pens, they were able to draw sensors to measure glucose directly onto the wrist of a willing participant. They say this ink drawing could be “easily interfaced with a Bluetooth-enabled” device that can provide the read-out.

The researchers also used the ink to draw on and measure chemicals on leaves, and according to Choi at IEEE Spectrum, “the inks could be modified to react with many other pollutants, such as heavy metals or pesticides”.

The main purpose of the ink, and probably the most immediate impact, will be to enable multiple-use testing strips for diabetes monitoring. As the authors note in their paper, handheld glucose metres rely on single use sensor strips, and each test is expensive for the user.

They demonstrated that when applied to a flexible strip that included an electrode, their ink functioned like a sensor. When a blood drop from a pricked finger was placed on the sensor, the ink reacted and the sensor measured this reaction, accurately determining the blood sugar level.

Importantly, the researchers say their ink only needs to be wiped off for the strip to be re-used - and they say one pen-load has enough ink for 500 tests.

The authors write that the most attractive feature of their pen “is the immense freedom available to incorporate high-fidelity inexpensive sensors of any design on a wide variety of surfaces with minimal user training.”

The same team has previously developed temporary tattoos to help diabetics continuously monitor their blood-sugar levels. They say the next step is to connect the sensors wirelessly to monitoring devices and test their performance in different climatic conditions.

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Wireless Energy Transfer: It's Reality

Think of a world where you could charge your phone while moving on without any wires, the car you drive can be powered on the go, moving through the Galaxy and not worrying about the fuel all this futuristic things are going to get true very soon, Scientists in Japan have announced that they've successfully managed to transmit energy wirelessly with high accuracy,and this is not the invention that occurs daily this COULD CHANGE THE FUTURE of our energy need.

The researchers from the Japan Aerospace Exploration Agency (JAXA) announced a day before yesterday that they had used microwaves to deliver 1.8 kilowatts of power - just enough to power a kettle - through the air to a receiver 55 metres away, with pinpoint accuracy, this technology had nothing to do with what we use these days to power our mobile wirelessly with the help of a magnetic field.


"This was the first time anyone has managed to send a high output of nearly two kilowatts of electric power via microwaves to a small target, using a delicate directivity control device," a spokesperson for JAXA told.

The ultimate aim of the team is to provide earth with solar energy that will be collected 36000km above earth's surface and will be transmitted to earth where it will be received by antennas. "But it could take decades before we see practical application of the technology - maybe in the 2040s or later," the spokesperson told.

"There are a number of challenges to overcome, such as how to send huge structures into space, how to construct them and how to maintain them."

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Saturn's Moon may contain sign of life

Pictorial representation of the thermal activity on Saturn's moon 

NASA's Cassini spacecraft has provided scientists the first clear evidence that Saturn's moon Enceladus exhibits signs of present-day hydrothermal activity which may resemble that seen in the deep oceans on Earth. The implications of such activity on a world other than our planet open up unprecedented scientific possibilities.

"These findings add to the possibility that Enceladus, which contains a subsurface ocean and displays remarkable geologic activity, could contain environments suitable for living organisms," said John Grunsfeld, astronaut and associate administrator of NASA's Science Mission Directorate in Washington. "The locations in our solar system where extreme environments occur in which life might exist may bring us closer to answering the question: are we alone in the universe."

Hydrothermal activity occurs when seawater infiltrates and reacts with a rocky crust and emerges as a heated, mineral-laden solution, a natural occurrence in Earth's oceans. According to two science papers, the results are the first clear indications an icy moon may have similar ongoing active processes.

The first paper, published this week in the journal Nature, relates to microscopic grains of rock detected by Cassini in the Saturn system. An extensive, four-year analysis of data from the spacecraft, computer simulations and laboratory experiments led researchers to the conclusion the tiny grains most likely form when hot water containing dissolved minerals from the moon's rocky interior travels upward, coming into contact with cooler water. Temperatures required for the interactions that produce the tiny rock grains would be at least 194 degrees Fahrenheit (90 degrees Celsius).

"It's very exciting that we can use these tiny grains of rock, spewed into space by geysers, to tell us about conditions on -- and beneath -- the ocean floor of an icy moon," said the paper's lead author Sean Hsu, a postdoctoral researcher at the University of Colorado at Boulder.

Cassini's cosmic dust analyzer (CDA) instrument repeatedly detected miniscule rock particles rich in silicon, even before Cassini entered Saturn's orbit in 2004. By process of elimination, the CDA team concluded these particles must be grains of silica, which is found in sand and the mineral quartz on Earth. The consistent size of the grains observed by Cassini, the largest of which were 6 to 9 nanometers, was the clue that told the researchers a specific process likely was responsible.

On Earth, the most common way to form silica grains of this size is hydrothermal activity under a specific range of conditions; namely, when slightly alkaline and salty water that is super-saturated with silica undergoes a big drop in temperature.

"We methodically searched for alternate explanations for the nanosilica grains, but every new result pointed to a single, most likely origin," said co-author Frank Postberg, a Cassini CDA team scientist at Heidelberg University in Germany.

Hsu and Postberg worked closely with colleagues at the University of Tokyo who performed the detailed laboratory experiments that validated the hydrothermal activity hypothesis. The Japanese team, led by Yasuhito Sekine, verified the conditions under which silica grains form at the same size Cassini detected. The researchers think these conditions may exist on the seafloor of Enceladus, where hot water from the interior meets the relatively cold water at the ocean bottom.

The extremely small size of the silica particles also suggests they travel upward relatively quickly from their hydrothermal origin to the near-surface sources of the moon's geysers. From seafloor to outer space, a distance of about 30 miles (50 kilometers), the grains spend a few months to a few years in transit, otherwise they would grow much larger.

The authors point out that Cassini's gravity measurements suggest Enceladus' rocky core is quite porous, which would allow water from the ocean to percolate into the interior. This would provide a h

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Compound that captures Carbon could save the environment

Global warming is a major concern which people are aware now but for the past few decades the condition was not as serious as it is now. The world is getting warmer. Whether the cause is human activity or natural variability—and the preponderance of evidence says it’s humans—thermometer readings all around the world have risen steadily since the beginning of the Industrial Revolution.
According to an ongoing temperature analysis conducted by scientists at NASA’s Goddard Institute for Space Studies (GISS), the average global temperature on Earth has increased by about 0.8° Celsius (1.4° Fahrenheit) since 1880. This may cause serious problems and to lower the earth temperature will ensure a safer future for our coming generation.

 A new mechanism for highly efficient CO2 uptake in carbon-capturing materials has been discovered by an international collaboration from EPFL’s Energy Center. The novel mechanism, published in Nature, offers an energy-efficient route to carbon capture. Metal-organic frameworks (MOFs) are porous crystal structures made from metal nodes that are connected through organic linkers. MOFs are at the center of carbon-capturing efforts, as they are chemically tunable and can adsorb(to make something staggered on or below the surface) carbon with high efficiency.

MOFs can be used to remove the carbon form the atmosphere to the factories where various forms of carbon like Co2, CH4 gases are produced. scientists have found that inserting CO2 in a metal-amine bond of MOFs can trigger a highly efficient chain reaction of CO2 uptake. The researchers took advantage of the chemical versatility of MOFs, and were able to optimize the conditions of the chain reaction by altering the metal atoms at the nodes of the MOF’s structure.

As a result of this, the MOFs can achieve large capacities in separating CO2 from the atmosphere with only small temperature changes. Meanwhile, the energy required to regenerate MOFs following release of captured CO2 was lower than even state-of-the-art liquid amine solutions. The two most promising MOFs were based on magnesium and manganese, and were able to operate at high temperatures.

The results provide a template for designing highly efficient adsorbent materials that can remove CO2 from various gas mixtures. Compared to available technologies, this design offers advantages in terms of reduced sorbent regeneration energy and reduced materials and system costs.

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Material that changes color like chameleons

The nature is the best creator and teacher it has teaches us many things the latest what scientists are able to get the idea from nature and implement it is that a new material skin has been prepared for the first time that changes its color on various occasion just the similar way a chameleon does.

This is the first time anybody has made a flexible chameleon-like skin that can change color simply by flexing it," said Connie J. Chang-Hasnain, a member of the Berkeley team and co-author on a paper published today in Optica, The Optical Society's (OSA) new high-impact journal.

Everything around us is visible to us by the fact it reflects a certain wavelength of the light falling on it and absorbing all other in it, and it is true that we cannot know the true color of any object because till date it is not possible to know what color wavelength has been absorbed by the object. But despite this we can see any color that falls in the visible range spectrum ranging from high wavelength of red to low wavelength violet.

It is possible to make a specific color reflect from the object in two ways one of which includes changing the chemical composition of the object and the other which is used by the scientists is that to make the surface in such a way that it reflects a certain wavelength of light. The authors of the Optica paper applied a similar principle, though with a radically different design, to achieve the color control they were looking for. In place of slits cut into a film they instead etched rows of ridges onto a single, thin layer of silicon. Rather than spreading the light into a complete rainbow, however, these ridges -- or bars -- reflect a very specific wavelength of light. By "tuning" the spaces between the bars, it's possible to select the specific color to be reflected. Unlike the slits in a diffraction grating, however, the silicon bars were extremely efficient and readily reflected the frequency of light they were tuned to.

"The next step is to make this larger-scale and there are facilities already that could do so," said Chang-Hasnain. "At that point, we hope to be able to find applications in entertainment, security, and monitoring." Even high levels of camouflage may be achieved with this or the materials that changes color with the change in stresses in them, in future gadgets or any other unknown features.

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Light travelling at less than the speed of light.

It's a challenge for the classical physics and our knowledge of science. In all of our text books we have read that light velocity depends on the medium in which it travels and is maximum in air or vacuum that is approximately 3*10^8 meter per second. 

But a new research paper published from University of Glasgow and Heriot-Watt University describe how they have managed to slow photons(light carrier) in free space for the first time, and they are able to do this by applying a mask to the optical beam which provided the photons for the experiment. The mask forced the photon to change its shape and travel slower than the speed of light.

In the experiment the scientists took two beams of light emitting photons to race together one was normal and the other beam was masked which changed the shape of the photons passing through it, this was one of the proof that light is of dual nature that is wave and particle, as only shape of waves can be changed. And when the photon after passing through mask was again in free air it took a very very small time to complete the 1 meter long race with the normal photon. This shows that once pattern has been imposed - even now the light is no longer in the mask, it's just propagating in free space - the speed is still slow. 

Professor Padgett the Scientists associated with the experiment added: “It might seem surprising that light can be made to travel more slowly like this, but the effect has a solid theoretical foundation and we’re confident that our observations are correct.

“The results give us a new way to think about the properties of light and we’re keen to continue exploring the potential of this discovery in future applications. We expect that the effect will be applicable to any wave theory, so a similar slowing could well be created in sound waves, for example". 

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Heat waves in 2-D Graphine : Future of electronics

Heat is something which makes us the sense of hotness or coolness of an object, heat is not as simple as it seems, but could you emagine that heat will be used for transmitting or receiving signals in the future electronic devices, at present we use electric signal for this purpose.
In a study published in Nature Communications, a team of EPFL researchers has shed new light on the mechanisms of thermal conductivity in graphene and other two-dimensional materials. They have demonstrated that heat propagates in the form of a wave, just like sound in air. This was up to now a very obscure phenomenon observed in few cases at temperatures close to the absolute zero. Traditionally heat can transfer via three modes conduction, convection and radiation. Radiation is the way by which heat transfer like waves but is solids the method governing heat transfer is conduction, but it is a great achievement that the phenomenon of heat through waves in graphine was achieved.
Generally in 3-d materials the heat transfers through the vibration called of atoms know as "phonons" that transfer energy to each other by the process of conduction and in this process it is not possible to transmit heat to long distance without losses. But the 2-d graphine can transmitt the heat in a reversible manner with the help of heart waves that suffer very less loss with the help the phenomenon of wave-like diffusion, called "second sound". In that case, all phonons march together in unison over very long distances. "Our simulations, based on first-principles physics, have shown that atomically thin sheets of materials behave, even at room temperature, in the same way as three-dimensional materials at extremely low temperatures" said the author of the study. He also says that not only graphine shows waves propagation property but various other elements are there which can show the similar results, which are yet to be tested.
This research will help the scientists and engineers which are keen to have a boom in the electronics technology replacing the Silicon.

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Sodium ion battery the future of electronic devices power supply

Lithium-ion batteries are the backbone of mostly all the electronic devices may it be your Android, iPhone, laptops or any other device the Li-ion batteries have served so well that in future there may be shortage of Lithium for the production of batteries if we are not able to get an alternative source of power.

Sodium could be used as an alternative for Lithium in the future batteries as it cheap, abundant and easily available but there lies some problems with sodium(Na) that the battery with Na-ion takes longer time to charge and it's discharge is so slow that it could not power high potential devices,but researchers led by Yong Lei, a professor at the Technical University of Ilmenau in Germany, have achieved a significant improvement in this area. The research claims that it has achieved the highest efficiency from a Na-ion battery which could challenge any Lithium battery in terms of charge and discharge.

To solve this problem there was a need to know the basics difference in reactions of both Na and Li. Sodium electronic configuration ends with 3s¹ whereas for Lithium it is 2s² which tells that both these metals can loose electrons which is required for a battery to operate but the size of sodium is larger so it is quite tough for Na ions to get absorbed or released by the electrods. However the size of sodium remains the same only the size of electrode was changed by molecule design strategy of pi-conjugated system, which basically involves manipulating the way that these molecules bond with each other. Physically, this strategy results in a terrace morphology, consisting of multiple, widely spaced layers that form a faster route for the sodium ions to move through. The extended π-conjugated system also improves the charge transport and stabilizes the charged and discharged states so that they can better tolerate the fast insertion/extraction of Na ions.

In terms of battery performance, this change results in significant improvements. As always, there is still a tradeoff between charge/discharge rates and capacity. But the new Na-ion batteries can operate at a current density (a measure of the charge/discharge rate) that is 1000 times higher (10 A/g vs. 10 mA/g) than most previously reported organic Na-ion batteries while retaining a much higher capacity (72 mAh/g).
At an intermediate current density (1 A/g), the new battery delivers an impressive reversible capacity of 160 mAh/g, which is one of the highest values reported for both organic Na-ion and Li-ion batteries to date. The battery also exhibits good capacity retention (70% retention after 400 cycles).

The scientists says that a lot of improvement has to be done to make this technology comes to your pocket but you have to wait for quiet some time.

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Dual nature of light filmed for the first time

Light is the only thing which makes everything visible and is the first thing which was formed after the big bang and knowing it better would ultimately lead to a science full future. Einstein was one of the first person to tell the world that light behaves in both nature that is wave and particle, since then a lot of studies have been done in the nature of light, even a branch of science quantum mechanics get its origination from this idea of light and it tells us that light can behave as both wave and particles at the same time but were are not able get the proof that this is possible simultaneously.

There were many occasions where light was photographed behaving like particle or like waves but for the first time a team at the Swiss Federal Institute of Technology in Lausanne (EPFL) has demonstrated an experiment which has captured the images of light behaving like waves and particles simultaneously.
The experiment is set up like this: A pulse of laser light is fired at a tiny metallic nanowire. The laser adds energy to the charged particles in the nanowire, causing them to vibrate. Light travels along this tiny wire in two possible directions, like cars on a highway. When waves traveling in opposite directions meet each other they form a new wave that looks like it is standing in place. Here, this standing wave becomes the source of light for the experiment, radiating around the nanowire.

This is where the experiment’s trick comes in: The scientists shot a stream of electrons close to the nanowire, using them to image the standing wave of light. As the electrons interacted with the confined light on the nanowire, they either sped up or slowed down. Using the ultrafast microscope to image the position where this change in speed occurred, which acts as a fingerprint of the wave-nature of light.

Experiment set up 

While this phenomenon shows the wave-like nature of light, it simultaneously demonstrates its particle aspect as well. As the electrons pass close to the standing wave of light, they “hit” the light’s particles, the photons. As mentioned above, this affects their speed, making them move faster or slower. This change in speed appears as an exchange of energy “packets” (quanta) between electrons and photons. The very occurrence of these energy packets shows that the light on the nanowire behaves as a particle.

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Artificial Photosynthesis :Future of fuels

Sun is the ultimate source of power if only for a day is all energy produced is stored it could fulfill the energy need of Earth for at least a thousand year. Sunlight is used for generating energy through the solar panels and the efficiency is almost 10% but it takes large numbers of solar panels for generating large amount of energy. Though photosynthesis may seems as a reverse process of using suns energy and converting it into glucose and oxygen, but this is the ultimate technique of getting sun energy into useful work. Plants do it all the time they convert sunlight into energy rich molecules with just carbondioxide, water and sunlight and of we are able to produce such a machine which could produce artificial photosynthesis then it would be a source of power with unlimited energy.

We are very close of generating such a device but the challenges lies in the process of oxidation of water and reduction of CO2, a research from Monash University has been able to recreate the photosynthesis process to produce methanol which is a fuel which can be used directly,and the efficiency of this process is higher than the natural photosynthesis. Various catalyst of copper dioxide are used for the oxidation of water and the reduction of carbondioxide and when the catalyst are coupled with materials that can absorb light fuels like methanol can be produced. If we are able to know the path followed by the process to occur and Researchers from institutions including Lund University have taken a step closer to producing solar fuel using artificial photosynthesis. In a new study, they have successfully tracked the electrons’ rapid transit through a light-converting molecule. The technique used is much difficult than the traditional solar panels but if we master this this will open a new corridors for energy which will be long lasting.

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Powerful Poop

A bus service started in the UK last year transporting 10000 persons per month from the Bristol airport to the city of bath but the thing which draws our attention is that the bus is powered by poop(human waste) for fuel, the city have enough people that there will be no shortage of fuel ever, the bus can travel a distance of 186 miles with the annual poop of just 5 people. Nasa is planning to go one step further, it is trying to get the fuel used for rockets which will be a great step in space industry as the fuel is a major challenge which stops us from covering large distances in space. I can assure you that today only you have flushed a tremendous source of power which could help the world in overcoming is power problems. As the technology grows our rate of power consumption is increasing rapidly and there is shortage of fuels like gasoline, diesel, natural gas etc, but there is one source that will last till the humans will last and it is your poop. An average person produces 360 pounds of poop in an year and if it is treated and used it could be enough to meet the basic power requirements of an individual. The food which we eat contains energy but all is not utilised by our body and is rejected in form of poop and this can be used again to extract the energy. A lot of technologies are working in this field and some have developed method of converting poop into energy which could be used as heat or work.

In India people uses cow dung as a source of fuel for the past 20 years or more where the dung is transported to a closed pit where it is allowed to degedrade which produces methane gas which is used for daily household work like cooking, heating, electricity etc. The same could be done from human poop but you need to forget about it while using it for cooking or heating. There are various companies like Black Gold Biofuel which process and converts poop into solid fuel which could be used to replace coal as a source of power. The Bioengineers at Oregon State University (OSU) have developed a microbial fuel cell that can treat waste water — and generate significant amounts of electricity at the same time. Consider what amount of energy can we produce of all the poop of 7 billion people can be used, wouldn't that be so stinky.

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