Month: August 2019

Creating a memory device out of paper

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. The voice is key to making sense of the words in our brain (PhysOrg.com) — As technology continues to shrink, and as memory needs become more demanding, the industry dealing with microelectronics requires devices that are cost-efficient and lightweight. And, while organic materials have shown some promise, they still lack some of the essential qualities needed for application in a wide variety of fields. “The longest time that has lasted from organic memories,” Rodrigo Martins tells PhysOrg.com, “is about 5,000 seconds. This just doesn’t allow for practical use in many cases as a memory device.” Martins, a scientist at the New University of Lisbon in Portugal, continues: “What we have shown is that it is possible to store information on paper, electronically, for more than a year and a half.” Martins is part of a team that includes Pedro Barquinha, Luís Pereira, Nuno Carreia, Gonçalo Gonçalves, Isabel Ferreira and Elvira Fortunato. The group has demonstrated memory performance using a field-effect transistor built on paper. Their work is published in Applied Physics Letters: “Write-erase and read paper memory transistor.”“What we are doing is exploiting the memory effect,” Martins explains. “We have a sort of type of integrated foam composed of fibers set up that increases the capability of storing carriers – or charges – in our paper.” These charges allow the paper to display information that is also erasable – and the paper is rewritable so that additional information can be added.One of the attractive features of this memory paper is that it is produced at room temperature, meaning that it does not need special conditions for its manufacture. To create the paper, long fibers from pine and polyester were mixed together and put into an ionic resin matrix. The fibers were then coated with gallium indium zinc oxide, using magnetron sputtering. “We have integrated discrete fibers, and contacts are applied on the extremes of the channel region to allow the induced carriers to move,” Martins says. “Electrons move along the fibers.”Martins points out that another of the attractive features of this paper is its ability to hold multiple layers of information. “If I want my paper to catch information,” he explains, “I can apply a signal of, say, five volts. And it writes on the paper. If I want to erase the information, I basically apply minus five volts – the opposite. But, at the same time, I can write another layer of information using 10 volts. The paper can distinguish between the two, and even if I erase the five volt information, the 10 volt information remains.”The main applications that Martins sees for this work right now involve product information for merchandise. “You can have multiple layers of information on a product label,” he says. “Instead of just the expiring date, you can have more than this, including information about when it went on the shelves.” However, Martins also sees the potential for this paper’s use in books. “You can create a display, bringing a new dimension to the paper,” he says. “You push a button and it changes. You can see a static or dynamic picture, or even another page.” “Such technology,” he cautions, “is still some years away. It will take five or six years to really work out how to use this technology to such an effect. But we do know that paper can store a great deal of information. We have the paper transistor; we have the memory. We have everything we need to make this happen.”More Information: Rodrigo Martins, Pedro Barquinha, Luís Pereira, Nuno Correia, Gonçalo Gonçalves, Isabel Ferreira, and Elvira Fortunato. “Write-erase and read paper memory transistor,” Applied Physics Letters (2008). Available online: link.aip.org/link/?APPLAB/93/203501/1 .Copyright 2007 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. center_img Citation: Creating a memory device out of paper (2008, November 26) retrieved 18 August 2019 from https://phys.org/news/2008-11-memory-device-paper.html Explore furtherlast_img read more

Israeli astrophysicists say neutron star collisions can help detect gravity waves

first_imgNeutron star collision. Image: NASA/Dana Berry This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Can you hear black holes collide? Citation: Israeli astrophysicists say neutron star collisions can help detect gravity waves (2011, September 29) retrieved 18 August 2019 from https://phys.org/news/2011-09-israeli-astrophysicists-neutron-star-collisions.html (PhysOrg.com) — Neutron stars are what’s left over from supernova explosions; so dense that protons and electrons are crushed together forming neutrons. The result is something relatively small in size, but incredibly dense. But what happens when two such stars capture one another in their respective gravity fields? More information: Detectable radio flares following gravitational waves from mergers of binary neutron stars, Nature (2011) doi:10.1038/nature10365AbstractMergers of neutron-star/neutron-star binaries are strong sources of gravitational waves. They can also launch subrelativistic and mildly relativistic outflows and are often assumed to be the sources of short γ-ray bursts. An electromagnetic signature that persisted for weeks to months after the event would strengthen any future claim of a detection of gravitational waves10. Here we present results of calculations showing that the interaction of mildly relativistic outflows with the surrounding medium produces radio flares with peak emission at 1.4 gigahertz that persist at detectable (submillijansky) levels for weeks, out to a redshift of 0.1. Slower subrelativistic outflows produce flares detectable for years at 150 megahertz, as well as at 1.4 gigahertz, from slightly shorter distances. The radio transient RT 19870422 has the properties predicted by our model, and its most probable origin is the merger of a compact neutron-star/neutron-star binary. The lack of radio detections usually associated with short γ-ray bursts does not constrain the radio transients that we discuss here (from mildly relativistic and subrelativistic outflows) because short γ-ray burst redshifts are typically >0.1 and the appropriate timescales (longer than weeks) have not been sampled. © 2011 PhysOrg.com Explore further Ehud Nakar and Tsvi Piran, university professors in Israel, say they circle one anther until eventually colliding and unleashing an enormous amount of energy. In their paper published in Nature, the two describe how a simulation they’ve created shows that energy particles emitted from such an occurrence could reach speeds of one tenth to one half the speed of light. They also write that such an event could produce measureable gravity waves.Gravity waves are something Einstein predicted as part of his theory of general relativity. Also described as the result of a space-time warp, gravity waves are thought to occur due to the existence of large mass objects. One analogy is a small stone placed upon a sheet of linen. Nothing happens. But when a large rock is placed on it instead, the linen bends around beneath it. The problem with trying to measure such gravity waves though, is that they dissipate as they move, just as do waves in water. Thus, waves that reach us after traveling billions of miles tend to be rather weak. Another problem is that they are one shot deals. Studying events in space is far more difficult than studying objects as they only last for a short while. Nakar and Piran believe that waves from a collision between two neutron stars would only be observable for a few months. Luckily, two new telescopes are currently being built to observe such phenomena; one in the US and one in the Netherlands.In order to prove their theory, the duo needs to come up with some evidence to show that measurable energy from such a collision has reached the Earth before. And they think they have found it: RT 19870422, a transient object discovered in a previous study by astronomer Jeffrey Bower. Its properties seem to match those created in the simulation. But of course if it sent gravity waves our way they are long gone, thus looking towards the future, the two will have to find two neutron stars that are on the verge of colliding, then hope that they will be able to capture the results when it happens.last_img read more

Researchers devise a way to measure volatile organic compound exchange in the

first_img VOCs are organic chemicals that exhibit high vapor pressure under normal conditions. Their high vapor pressure tendencies are due to their low boiling point, which in turn result in their molecules evaporating and winding up in the atmosphere. Prior research has shown that there are a large number of such chemicals in the atmosphere, but environmental conditions have made it difficult to isolate and identify these chemicals from any given sample. For that reason, researchers have primarily focused almost exclusively on a chosen few, such as isoprene, methanol, and various terpenes. In this new effort, the team has put together two devices that allow not only for monitoring all of the VOCs that exist in the air at a certain location, but also whether the VOCs are being emitted or deposited.Neither device is new, they are just being used in a new way. The first is a mass spectrometer. The team installed it atop a pole at Gordon Ranch along with gas inlets and an anemometer. The spectrometer collects chemical samples while the anemometer detects changes in wind direction. This combination allows the team to discern if readings picked up by the spectrometer are from chemicals being put into the air (wind moving upwards) or taken out (wind moving downward). This novel arrangement allows the researchers to monitor the total exchange of VOCs in the air above the orange grove for a short period of time.Going in, the team expected to find a few new compounds in the air—they were surprised, however, to find they had detected hundreds of VOCs. Their effort marks the first time a research team has been able to identify the entire exchange of VOCs in a portion of the atmosphere.The team notes that their research effort was limited to one site and that monitoring other sites could result in vastly different findings. More importantly, it appears their technique could be used to monitor sites all around the world, giving environmental scientists much more information about what is going on in the atmosphere, including of course, global warming. Explore further © 2013 Phys.org (Phys.org) —A team of researchers from the U.S., the Netherlands, and Italy has found a way to detect and measure the exchange of volatile organic compounds (VOCs) in the atmosphere. In their paper published in the journal Science, the team describes how they used a new technique to measure VOC concentrations in the air above an orange grove in California. Scent of melanoma: New research may lead to early non-invasive detection and diagnosis Citation: Researchers devise a way to measure volatile organic compound exchange in the atmosphere (2013, August 9) retrieved 18 August 2019 from https://phys.org/news/2013-08-volatile-compound-exchange-atmosphere.htmlcenter_img More information: Active Atmosphere-Ecosystem Exchange of the Vast Majority of Detected Volatile Organic Compounds, Science 9 August 2013: Vol. 341 no. 6146 pp. 643-647 DOI: 10.1126/science.1235053ABSTRACTNumerous volatile organic compounds (VOCs) exist in Earth’s atmosphere, most of which originate from biogenic emissions. Despite VOCs’ critical role in tropospheric chemistry, studies for evaluating their atmosphere-ecosystem exchange (emission and deposition) have been limited to a few dominant compounds owing to a lack of appropriate measurement techniques. Using a high–mass resolution proton transfer reaction–time of flight–mass spectrometer and an absolute value eddy-covariance method, we directly measured 186 organic ions with net deposition, and 494 that have bidirectional flux. This observation of active atmosphere-ecosystem exchange of the vast majority of detected VOCs poses a challenge to current emission, air quality, and global climate models, which do not account for this extremely large range of compounds. This observation also provides new insight for understanding the atmospheric VOC budget. Journal information: Science . Flux contribution by chemical composition. Credit: Science 9 August 2013: Vol. 341 no. 6146 pp. 643-647 DOI: 10.1126/science.1235053 This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Protein chains that selfform into helical braids

first_imgSEM micrographs of braid topologies observed in gels of 2. a, Cartoon diagrams showing two-stranded entanglements and their corresponding braid words. The braid word describes the pattern of crossings in the repeat unit, which must conform to certain topological constraints. b,c, Commonly observed entanglements in gels of 2: double helices (b) and larger helical bundles (c). d,e, Three- and four-stranded entanglements observed in gels of 2: three-stranded Brunnian braids (d) and tentative examples of nested homochiral double helices (e). Credit: Nature Chemistry (2019). DOI: 10.1038/s41557-019-0222-0 A team of researchers from Durham University in the U.K. and Shaanxi Normal University in China has discovered a type of protein that forms naturally into two main types of helical braids. In their paper published in the journal Nature Chemistry, the group describes extracting an achiral oligo peptidomimetic compound from a urine sample and observing its unique properties. More information: Christopher D. Jones et al. Braiding, branching and chiral amplification of nanofibres in supramolecular gels, Nature Chemistry (2019). DOI: 10.1038/s41557-019-0222-0 Tiny protein coiled coils that self-assemble into cages Citation: Protein chains that self-form into helical braids (2019, March 5) retrieved 18 August 2019 from https://phys.org/news/2019-03-protein-chains-self-form-helical-braids.html Explore furthercenter_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Prior research has shown that proteins can form themselves into interesting shapes because they develop naturally into chains. Scientists have also learned that the shape a chain takes depends on its amino acid sequence. The study of protein shapes assumed great importance in recent years after it was found that misfolding can lead to conditions such as mad cow disease, in which amyloid fibers form braids and clump together, causing neural damage. The formation of amyloid fibers is also a hallmark of Alzheimer’s disease. In this new effort, the researchers took a closer look at a protein that exists naturally in urine to learn more about its shape characteristics.The researchers found that the protein naturally takes on one of two main types of shapes—one is a four-strand braid in a quadruple helix, and the other consists of pairs of double helices that weave themselves together into a single strand.The researchers found that aggregating the helices resulted in the formation of braided fibrils. They also found that branching occurred in the braids when errors cropped up, resulting in the formation of intricate patterns of connected braids. They also discovered that mixed-chirality helices assembled themselves into complex braid formations, but sometimes formed bundles if they underwent chirality inversion. They also noted that the protein chains were very sensitive to chiral amplification, which makes them good candidates for creating gels. The researchers created a gel using these chains in their lab, and report that it was similar in some respects to other gels already used in pharmaceuticals They also report that the gel is stickier than those typically used in pharmaceutical applications, which might make them good candidates for new applications. They also point out that the way the braids are formed can be engineered, which means it should be possible to create gels with different characteristics. © 2019 Science X Network Journal information: Nature Chemistrylast_img read more

Want to continue with theatre

first_imgMaking a comeback to theatre is a fascinating experience for Bollwyood’s well-known actor Om Puri, who will be performing in the Capital, offering a complete treat to Delhiites. This marks the veteran actor’s return to the stage after 25 years.He will stage a comeback with Teri Amrita at the Punjabi Theatre Festival. This play is an Indian adaptation of AR Gurney’s Pulitzer Prize-nominated play Love Letters (1988). The play will highlight the professional journey of Puri and Divya Dutta, who will play the roles of Zulfikar Haider and Amrita Nigam, respectively. Also Read – ‘Playing Jojo was emotionally exhausting’Talking about making his way back to acting on stage, Om Puri said: ‘I was very nervous initially when I decided to make a comeback. I started off with theatre as a teenager and was spotted by directors of the Punjab Kala Manch at a college play. Now at this point of life, when I am turning 64, I want to continue with theatre. I want to act and will be producing theatre from now on.‘I have no illusions about myself. It’s very difficult to get good meaningful roles in films today, unless you happen to be a huge star, where roles get specially written for you,’ admits Puri. Also Read – Leslie doing new comedy special with NetflixThis play is a love story told through letters exchanged between the two protagonists, Zulfikar Haider and Amrita Nigam, over 35 years. Set during the time of Indo-Pak Partition, the two meet as children and form the bond which has been depicted by the play. It reflects the passage of time through the soured dreams and doomed love between the two lovers who pursue different paths, yet keep the flame of love alive through their evocative letters. A girl with soaring aspirations, Amrita (Divya Dutta) writes about her deepest emotions to her childhood beloved Zulfi (Om Puri), who reciprocates his unconditional love in his replies to her. Punjabi Theatre Festival will be organised by the Department of Art, Culture and Languages, under the government of India and Punjabi Academy. This is an initiative taken by chief minister of Delhi Sheila Dikshit.‘We are very excited to showcase the event. The return of famous actor Om Puri will stir up the audience. We are expecting a huge footfall at the event. I am very thankful to actors like Om Puri and Divya Dutta who have made a comeback to theatre. This will not only promote theatre but will encourage a lot number of famous celebrities to come back to theatre,’ said Rawail Singh.DETAILAt: Shri Ram Centre, Mandi House When: 19-22 December 19-22 Timings: 6.30 pm onwardslast_img read more

Magazines take flight

first_imgMaXposure Media Group to introduce inflight magazine of Biman Bangladesh Airlines The national carrier of Bangladesh, Biman Bangladesh Airlines’ flies to 18 destinations, including 14 international cities. Leaving behind seven publishing houses from UK, Fiji, India and Bangladesh, MaXposure Media Group (MaXposure) has bagged the contract for publishing Biman Bangladesh Airlines’ inflight magazine. MaXposure Media Group is scheduled to bring out the bi-monthly issue of Biman Bangladesh Airlines  (Biman) inflight magazine from September 2013 onwards. Keeping the airline’s wide network in mind, the magazine would be bilingual – to be published in English and Bengali. The name of the magazine will be announced soon.  Also Read – ‘Playing Jojo was emotionally exhausting’Speaking on the occasion Prakash Johari, Managing Director and CEO, MaXposure Media Group said, ‘I am proud to announce that MaXposure Media Group has won the bid to publish Biman inflight magazine.  This is inline with MaXposure’s Internationalisation strategy. Bangladesh with a population of 163 million enjoys a GDP growth of 6.1% and this makes it an ideal time for us to enter this growing market. Bangladesh is a strategic market for us and we intend to play a key role in its publishing industry.’ Also Read – Leslie doing new comedy special with NetflixKevin J Steele, Managing Director and CEO, Biman Bangladesh Airlines said, ‘Biman Bangladesh Airlines is delighted to be working with MaXposure on the new Biman inflight Magazine. MaXposure has a pedigree of working with top quality brands like Lufthansa and Mercedes, which adequately reflect the brand aspirations of Biman.  This is a win-win situation for both parties, and Biman is delighted to once again have a quality inflight magazine to offer its customers, yet another step in its major refocus on the customer.’ In the inflight segment, MaXposure currently publishes Shubh Yatra, the inflight magazine of Air India – India’s national carrier as well as Spiceroute, the monthly inflight magazine of SpiceJet Airlines.  After consolidating its position in India, the company has recently entered the international market after bagging the magazine publishing rights of Fly Africa, a South African low cost airline. With Biman Bangladesh Airlines’ magazine, MaXposure has put its mark in South Asia as well.  Talking about the inflight magazine Vikas Johari, Publisher and COO said ‘With MaXposure’s experience in publishing several global inflight magazines, we are looking forward to delivering an equally exciting world-class magazine for Biman. The magazine would aim at not only giving a pleasant reading experience to the flyers but also act as a mouth-piece to communicate with its stake holders.’last_img read more