Organic ternary data storage device developed

first_img A Glimpse of the Future MEMS-based Storage: Totally Green & Thumbnail Size SEM image of the device (the thickness of the azo1 film is about 120 nm.) Image credit: Journal of the American Chemical Society Image credit: Journal of the American Chemical Society More information: A Small-Molecule-Based Ternary Data-Storage Device, J. Am. Chem. Soc., Article ASAP, DOI:10.1021/ja910243f 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. A group of scientists, led by Ritesh Agarwal at the University of Pennsylvania, have previously used inorganic compounds to develop a reliable ternary data storage that is erasable, but Lu and Gu’s prototype is the first reliable ternary system using an organic compound in a permanent data storage device.High-density data storage (HDDS) systems are needed to store the ever increasing amounts of information. The prototype developed at Soochow University could lead to a massive increase in the potential memory density in future electronics devices.The paper is published in the Journal of the American Chemical Society. Explore further Citation: Organic ternary data storage device developed (2010, April 14) retrieved 18 August 2019 from https://phys.org/news/2010-04-ternary-storage-device.html © 2010 PhysOrg.com (PhysOrg.com) — The memory capacity of electronics devices could be increased in future thanks to an organic data storage system using ternary rather than binary data storage. The current prototype is designed for permanent data storage, and can be written once but read multiple times, but the Chinese researchers hope to develop re-writable data storage based on the technology. Binary systems record data as a switchable series of zeros and ones, whereas ternary systems record data as zeros, ones or twos, which are also electrically switchable states. The extra value theoretically means much more data could be stored in the same amount of storage space. Ternary systems already exist, but are mostly experimental.A new system, developed by Hongwei Gu and Jianmei Lu and colleagues at Soochow University, Suzhou in eastern China, is a ternary system using a new synthesized organic azo compound sandwiched between aluminum and indium tin oxide (ITO) electrodes. Each electrode unit acts as a data storage unit, which acts in a similar way to the magnetized patches in a hard disk that store data. When a voltage is applied to the aluminum electrode, the ease of electron flow (and density of molecular stacking) in the azo compound is changed to a low, medium or high conductivity state that corresponds to zero, one, or two respectively.last_img read more

Dynamic Vision Sensor tech works like human retina

first_img Explore further Citation: Dynamic Vision Sensor tech works like human retina (2013, August 26) retrieved 18 August 2019 from https://phys.org/news/2013-08-dynamic-vision-sensor-tech-human.html (Phys.org) —If technology expertise can advance artificial intelligence, what can we imagine for artificial vision? An interesting development in artificial vision comes from a Swiss company iniLabs. They have developed a camera that behaves like the human eye, based on the wonders of the human retina. Just as robotics developers take their cues from biology, this Swiss team has recognized how biology can inspire an alternative to conventional machine vision. The workings of the human eye require far less power than a digital camera would require and leave less information to be processed. Borrowing from the way the eye functions, the company has built a more efficient digital camera. Vision sensors keep their eye on the ball at Euro 2008 © 2013 Phys.orglast_img read more

Best of Last Week – Science that stumped Einstein revising human timeline

first_img © 2014 Phys.org Biology was big last week as scientists revised the timeline of human origins—a team of researchers has found evidence that suggests that perhaps some of the traits we define as uniquely human developed at different times, rather than all together during one period as has been thought. Another team wondered which happened first: Did sounds form words, or words form sentences? They’ve found evidence (by studying animals) that suggests early humans developed syntax before phonemes (distinct sounds that differentiate words from one another). And yet another team has unveiled what may be the core of our existence as the evolution of life’s operating system is revealed in detail—they’ve shed light on many new aspects of the evolution of the ribosome—the large molecular structure common to all cell species.On the medical front really big news from Cancer Research UK—Four in 10 pancreatic cancers could be prevented by lifestyle changes. If people would only maintain a healthy weight, quit smoking and maybe get some exercise, the researchers report, they’d drastically reduce their chance of getting one of the most deadly types of cancer.It was a pretty good week for technology development as well. A team of researchers built a biological robot and showed muscle-powered bio-bots walk on command. The bots were propelled by muscle cells zapped with an electric current. Also Cubify announced Ekocycle 3D printer uses recycled plastic bottles as component in filament cartridges—Entertainer Will.i.am is pushing the idea of making recycling “cool.”And finally, food for thought as a team has found that having something to do is better than being alone with their thoughts for most people. Turns out, people don’t do well when left to sit and ponder—they don’t like it. They’d much rather have something to do, even if it means hurting themselves. 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. Citation: Best of Last Week – Science that stumped Einstein, revising human timeline and a simple way to reduce pancreatic cancers (2014, July 7) retrieved 18 August 2019 from https://phys.org/news/2014-07-week-science-stumped-einstein-human.html Explore furthercenter_img Remote quantum applications, teleportation enabled by calling long distance between superconducting qubits (Phys.org) —For 112 years, the best minds in science haven’t been able to fully understand how superconductors do what they do. Last week, Louise Lerner of Argonne National Laboratory, published an article reminding everyone of the science that stumped Einstein, suggesting that perhaps it’s time someone figured it out. In other physics news, a team of researchers reported: Remote quantum applications, teleportation enabled by calling long distance between superconducting qubits. They’ve developed a way to allow superconducting quantum chips to communicate with each other over large distances—through an optical fiber cable, which should, they claim, allow for quantum entanglement or teleportation. Schematic of the superconducting optical interfacelast_img read more

Researchers uncover tomatos genetic history

first_img © 2014 Phys.org , Nature Genetics Two years after the sequencing of the genome of one variety of tomato, scientists have sequenced the genomes of 360 tomato varieties. By analyzing the relationships among these genomes, Sanwen Huang of the Institute of Vegetables and Flowers at the Chinese Academy of Agricultural Sciences and his colleagues have reconstructed the genetic history of the tomato, from its origins as a pea-sized wild plant growing in South America’s Andes region to the many varieties found worldwide today. The research appears in Nature. More information: Nature Genetics (2014) DOI: 10.1038/ng.3117 Explore further Journal information: Naturecenter_img Citation: Researchers uncover tomato’s genetic history (2014, October 14) retrieved 18 August 2019 from https://phys.org/news/2014-10-uncover-tomato-genetic-history.html Wild tomato species focus of antioxidant study The tomato is the world’s leading vegetable crop. In 2012, global harvests yielded more than 162 million tons of tomatoes, worth more than 55 billion dollars. Understanding how the tomato’s genetic profile affects its taste, size and hardiness could increase consumer satisfaction while making the tomato industry even more profitable. That same year, Huang was part of a team of researchers who sequenced the genome of the Heinz 1706 variety of tomato, a processing tomato used to make ketchup. Huang and his current team knew that to improve breeding processes, scientists must understand the genetic profiles of the many different tomato varieties that exist today and the relationships between them. The researchers wanted to learn how the tomato genome has changed since the fruit was first domesticated, and then transported around the globe and bred for commercial purposes. They sequenced the genomes of 333 varieties of red tomato, 10 varieties of wild tomato and 17 modern commercial hybrids. They studied the change in the tomato’s size over time and found that the increase in tomato size since its domestication had involved a two-step process. At first, selection for size, the primary purpose of tomato breeding, resulted in the creation of cherry tomatoes. Big-fruited tomatoes appeared later.Huang’s team was able to identify the genetic differences between processing tomatoes and big-fruited tomatoes, which consumers eat fresh. Processing tomatoes are hardier, with more soluble fruit content and lycopene content, than big-fruited tomatoes. The researchers found the genetic signature for the processing tomato, with the genes responsible for its phenotype located on chromosome 5.They also located the gene that makes some tomatoes pink on chromosome 1. While globally, red-fruited tomatoes are most popular, pink-fruited tomatoes are very popular in China and Japan.Despite the wide variation in tomato phenotypes that exist today, Huang and his colleagues found that there is, in fact, very little genetic variation among the modern tomato varieties. Human selection has fixed a large proportion of the tomato genome. 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

New evidence that global warming will hurt US wheat production

first_img As the planet continues on its apparently inevitable march to a warmer future, scientists the world over are scrambling to understand what impact it will have—from rising ocean levels to crop production. In this latest effort, the researchers sought to find out what might happen to wheat yields in the United States as temperatures rise. To say that wheat is an important crop is an understatement, it accounts for 20 percent of total daily calories consumed by humans across the globe, and represents a far higher ratio for many people in third world countries. Scientists have been working hard for many years to increase the amount of wheat grain that a farmer can get from a given field—currently such yields are still seeing increases of approximately 1 percent each year, which is remarkable. But that may change soon, this newest research suggests.For over thirty years, winter wheat trials have been taking place in Kansas, home to one of the largest producers of wheat—$2.8 billion worth in 2013 alone. That trial has yielded a lot of data, some of which the research team found indicated that modern strains are vulnerable to both extremely high and low temperatures. The low temperatures are not much of a concern in this study of course, but the high temperatures appeared to cause significant yield reductions—they even found a cutoff point—34 degrees Celsius. Overall they found a 15 percent reduction in yields when temperatures rose on average just 2 degrees Celsius and a 40 percent decline when average temperatures went up just 4 degrees. Sadly, they also found that more modern plants were more vulnerable than older strains.What this means, the researchers suggest, is that places that currently grow wheat are likely to suffer as global warming progresses. Currently, it is not clear if land lying north, where it will presumably be colder, will be able to support the level of predicted yield needs for the future. Credit: Wikipedia © 2015 Phys.org Study finds climate change may dramatically reduce wheat production Explore further (Phys.org)—A trio of researchers, one each from Mississippi State University, Kansas State University and the University of Arkansas has found evidence that suggests global warming will cause a reduction in U.S. wheat production in the years ahead. In their study published in Proceedings of the National Academy of Sciences, Jesse Tack, Andrew Barkley and Lawton Lanier Nalley describe how they studied winter wheat production for an area in Kansas and compared it against weather data and what they found by doing so.center_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. Citation: New evidence that global warming will hurt US wheat production (2015, May 12) retrieved 18 August 2019 from https://phys.org/news/2015-05-evidence-global-wheat-production.html More information: Effect of warming temperatures on US wheat yields, Jesse Tack, DOI: 10.1073/pnas.1415181112 AbstractClimate change is expected to increase future temperatures, potentially resulting in reduced crop production in many key production regions. Research quantifying the complex relationship between weather variables and wheat yields is rapidly growing, and recent advances have used a variety of model specifications that differ in how temperature data are included in the statistical yield equation. A unique data set that combines Kansas wheat variety field trial outcomes for 1985–2013 with location-specific weather data is used to analyze the effect of weather on wheat yield using regression analysis. Our results indicate that the effect of temperature exposure varies across the September−May growing season. The largest drivers of yield loss are freezing temperatures in the Fall and extreme heat events in the Spring. We also find that the overall effect of warming on yields is negative, even after accounting for the benefits of reduced exposure to freezing temperatures. Our analysis indicates that there exists a tradeoff between average (mean) yield and ability to resist extreme heat across varieties. More-recently released varieties are less able to resist heat than older lines. Our results also indicate that warming effects would be partially offset by increased rainfall in the Spring. Finally, we find that the method used to construct measures of temperature exposure matters for both the predictive performance of the regression model and the forecasted warming impacts on yields. Journal information: Proceedings of the National Academy of Scienceslast_img read more

Statistical study offers evidence of warning signs before Neolithic community collapse

first_img Citation: Statistical study offers evidence of warning signs before Neolithic community collapse (2016, August 30) retrieved 18 August 2019 from https://phys.org/news/2016-08-statistical-evidence-neolithic-collapse.html 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. (Phys.org)—A trio of researchers, two with the University of Maryland and the other with University College London has found that early Neolithic communities exhibited warning signs before collapsing. In their paper published in Proceedings of the National Academy of Sciences, Sean Downey, W. Randall Haas, Jr. and Stephen Shennan describe the statistical analysis they conducted on data that has been collected through prior efforts from Neolithic communities that existed approximately 9,000 years ago and what they learned as a result. Knowing when a given community, town or city is about to collapse could prove useful in the future as the planet continues to warm—how such communities responded to stresses that have occurred in the past, the researchers found, may offer clues to the robustness of modern communities.The European Neolithic was a time of huge population growth as agriculture allowed people to move into larger and larger communities and that allowed for technological advancement as many people discovered they no longer needed to spend their days hunting or growing food. But it was also a time of instability as increased population densities allowed diseases to spread more easily. There was also war and the always problematic unpredictable weather. Sometimes, such events led to the total collapse of a community. But before that happened, the researchers with this new effort contend, there were warning signs.To learn more about societal collapse during the Neolithic, the researchers pored over papers documenting archeological digs looking for population numbers along with information regarding evidence of prior events that may have signaled coming trouble. The focus of their research was how communities had responded to stresses in their recent past. Those that were not able to fully recover between events, they noted, were at the most risk of total collapse when a new event occurred. They dubbed such events early warning signals (EWSs). They then tried the opposite approach, looking first for EWSs for a given community and then using them to try to predict whether a given community eventually collapsed—they report that they found such signals to be remarkably accurate. They suggest similar models could be used to help predict which if any modern communities may be in for a similar fate. Explore further More information: Sean S. Downey et al. European Neolithic societies showed early warning signals of population collapse, Proceedings of the National Academy of Sciences (2016). DOI: 10.1073/pnas.1602504113AbstractEcosystems on the verge of major reorganization—regime shift—may exhibit declining resilience, which can be detected using a collection of generic statistical tests known as early warning signals (EWSs). This study explores whether EWSs anticipated human population collapse during the European Neolithic. It analyzes recent reconstructions of European Neolithic (8–4 kya) population trends that reveal regime shifts from a period of rapid growth following the introduction of agriculture to a period of instability and collapse. We find statistical support for EWSs in advance of population collapse. Seven of nine regional datasets exhibit increasing autocorrelation and variance leading up to collapse, suggesting that these societies began to recover from perturbation more slowly as resilience declined. We derive EWS statistics from a prehistoric population proxy based on summed archaeological radiocarbon date probability densities. We use simulation to validate our methods and show that sampling biases, atmospheric effects, radiocarbon calibration error, and taphonomic processes are unlikely to explain the observed EWS patterns. The implications of these results for understanding the dynamics of Neolithic ecosystems are discussed, and we present a general framework for analyzing societal regime shifts using EWS at large spatial and temporal scales. We suggest that our findings are consistent with an adaptive cycling model that highlights both the vulnerability and resilience of early European populations. We close by discussing the implications of the detection of EWS in human systems for archaeology and sustainability science.center_img Journal information: Proceedings of the National Academy of Sciences Ancient dental plaque sheds new light on the diet of Mesolithic foragers in the Balkans A regime shift model of population growth rate variability, radiocarbon date calibration, and EWSs that demonstrates CSD in growth rates can be recovered from simulated SPDs. Credit: Proceedings of the National Academy of Sciences (2016). DOI: 10.1073/pnas.1602504113 © 2016 Phys.orglast_img read more

Researchers report observation of roomtemperature polar skyrmions

first_imgObservation of ordered polar structure. a, b, Cross-sectional dark-field TEM images of a (SrTiO3)16/(PbTiO3)16/(SrTiO3)16 trilayer (a) and a [(SrTiO3)16/(PbTiO3)16]8 superlattice (b), revealing a regular in-plane modulation of about 8 nm. c, d, Planar-view dark-field STEM imaging shows the widespread occurrence of nanometre-size round and elongated features in a (SrTiO3)4/(PbTiO3)11/(SrTiO3)11 trilayer (c) and only circular features in a [(SrTiO3)16/(PbTiO3)16]8 superlattice (d) along the [100] and [010] directions. The STEM studies were repeated in a minimum of 10 separate samples and the observations were repeatable. Insets, FFT of the images in c and d show a ring-like distribution with stronger intensities along the cubic directions—the same feature seen in RSM studies. Credit: Nature (2019). DOI: 10.1038/s41586-019-1092-8 Simulation of a single polar skyrmion. Red arrows signify that this is a left-handed skyrmion. The other arrows represent the angular distribution of the dipoles. Credit: Xiaoxing Cheng, Pennsylvania State University; C.T. Nelson, Oak Ridge National Laboratory; and Ramamoorthy Ramesh, Berkeley Lab Zubko describes skyrmions as “tiny whorls of magnetic moments,” and notes that a lot of research has been done with them because they are very useful in data storage applications. But he also notes that finding electrical versions of skyrmions has been a difficult journey. That may change, however, as the researchers with this new effort report a way to create and observe at least one kind of electrically based skyrmion—the polar skyrmion.Zubko notes that the researchers started with the observation that ferroelectrics and ferromagnetics, despite being very different, have some basic similar properties—spontaneous magnetization and polarization are just one example. He suggests it is this property that makes both such a draw for data storage applications. He also notes that scientists have been searching for some time for polarization in ferroelectrics that rotate in a way that could lead to the creation of skyrmions. Prior work has shown that when ferroelectrics are confined at the nanoscale, they become more sensitive to stresses and electric fields, which can upset polar orientation and give way to dipoles. In such scenarios, small regions of dipoles with the same orientation can form spontaneously and those regions will have boundary walls separating them from other regions. More information: S. Das et al. Observation of room-temperature polar skyrmions, Nature (2019). DOI: 10.1038/s41586-019-1092-8Press release Journal information: Nature Army-funded research discovery may allow for development of novel device structures that can be used to improve logic/memory, sensing, communications, and other applications for the Army as well as industry. Image demonstrates simulation of emergent chirality in polar skyrmions for the first time in oxide superlattices. Credit: Xiaoxing Cheng, Pennsylvania State University; C.T. Nelson, Oak Ridge National Laboratory; and Ramamoorthy Ramesh, University of California, Berkeley Physicists show skyrmions can exist in ferroelectrics Explore further Citation: Researchers report observation of room-temperature polar skyrmions (2019, April 18) retrieved 18 August 2019 from https://phys.org/news/2019-04-room-temperature-polar-skyrmions.html In their work, the researchers noted that the domain walls had polarization components that were perpendicular to those that resided next to them. They found that all it took was looping a domain wall between regions to force a ring of polarization to develop, which led to the creation of bubbles—polar skyrmions. The team then used an electron microscope that was capable of showing atomic displacement to observe the skyrmions. They further report that X-ray diffraction of the skyrmions showed them to have macroscopic chirality. Zubko suggests that much more work will need to be done with the skyrmions to find out if they will work with real-world applications, such as racetrack memory devices. Simulation of a single polar skyrmion. Red arrows signify that this is a left-handed skyrmion. The other arrows represent the angular distribution of the dipoles. Credit: Xiaoxing Cheng, Pennsylvania State University; C.T. Nelson, Oak Ridge National Laboratory; and Ramamoorthy Ramesh, Berkeley Lab Army-funded research discovery may allow for development of novel device structures that can be used to improve logic/memory, sensing, communications, and other applications for the Army as well as industry. Image demonstrates simulation of emergent chirality in polar skyrmions for the first time in oxide superlattices. Credit: Xiaoxing Cheng, Pennsylvania State University; C.T. Nelson, Oak Ridge National Laboratory; and Ramamoorthy Ramesh, University of California, Berkeley © 2019 Science X Network An international team of researchers has discovered a way to create and observe room-temperature polar skyrmions. In their paper published in the journal Nature, the group describes creating the polar skyrmions and their observations. Pavlo Zubko, with the London Centre for Nanotechnology, has published a News and Views piece on the work done by the team in the same journal issue. 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

Call for all

first_imgThe residents of Sonia Vihar, Delhi, came up with a new initiative to promote clean river Yamuna. A one -day festival was celebrated by the Delhites at the bank of the river. The festival was a part of Yamuna aarti started by the local people of Sonia Vihar and surrounded areas. The event started with a kite festival that was attended by over hundred people from across the city. A street play, Kuch Baat Ho by Black Pearl Art was also organised that imparted the message to save and clean the natural resources.last_img