Kondo effect in single magnetic molecules

Kondo effect in single magnetic molecules

31 August 0

first_imgThe Kondo effect was first explained more than 40 years ago by a Japanese physicist. It opened a new chapter in the study of fundamental physics. Now, that door is being pushed open a little further, thanks to the efforts of a team of physicists at the Institute for Theoretical Physics in Aachen, Germany. Their paper, published May 17th in Physical Review Letters, is titled “Quantum-Tunneling-Induced Kondo Effect in Single Molecular Magnets,” and it offers possibilities for the further study of molecular transport. Citation: Kondo effect in single magnetic molecules (2006, June 7) retrieved 18 August 2019 from https://phys.org/news/2006-06-kondo-effect-magnetic-molecules.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.center_img “The Kondo effect is known from a variety of systems,” explains Walter Hofstetter, one of the authors of the paper. “However, this is the first time that it has been predicted in a magnetic molecule.” Hofstetter and his colleagues believe this discovery can be used to create a device that can be used as a spectroscopy tool that can be used to take various measurements on a quantum level.Jun Kondo found that as the temperature approaches 0 K, the electrical resistance of an atom will be anomalously enhanced. This is known as the Kondo effect, and it represents the first known example of a situation in physics known as asymptotic freedom. Asymptotic freedom is demonstrated by coupling that, at low energies and temperatures, become non-perturbatively strong. “Until now,” Hofstetter tells PhysOrg.com, “the assumption was that this effect didn’t take place in magnetic molecules.”Hofstetter and his peers have turned that assumption in its head. “There is an interplay between two effects of magnetic anisotropy in magnetic molecules, of which the first one is indeed detrimental to the Kondo effect. Using basic methods, we calculate the temperatures for the Kondo effect to show up. The new thing we discovered was that the second effect of anisotropy, the famous quantum tunneling of the molecular magnet, completely restores, and even enhances, the Kondo effect.” “The other interesting note about this process,” Hofstetter notes, “is that the electrons involved will behave as though they have only two spin states. This is remarkable because the spin would be, in actuality, much greater. In some case the spin would be greater than 10. But even with so many spin states it behaves as if it has a spin of 1/2.”Hofstetter says that there are “lots of practical applications in the future. The main value of this discovery is that it is a very good way to get information about molecular transport.” He and his colleagues have shown in more recent calculations that the discovery could lead to a spectroscopy tool that could find magnetic states.“With such a spectroscopy tool,” Hofstetter explains, “You could characterize better, and get more information. It is an important first step in eventually building other devices.” He goes on to point out that when it comes to building devices of such small dimensions, such that they operate on the quantum level, a tool that can help measure such small particles is quite useful. And Hofstetter and his collaborators aren’t the only scientists who think so. He says that there are already physicists working on electron transport experiments that could make use of this discovery when it comes to analyzing the characteristics and states of magnetic molecules.“Trapping molecules is a big challenge,” Hofstetter says. “There are few that have done it. So any tool that could help experimentalists understand the molecules that they do have better would be helpful.”By Miranda Marquit, Copyright 2006 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.last_img read more

Read More

Researchers develop algorithm to maximize friendship acceptance by strangers on social networks

31 August 0

first_imgThe running example. Credit: arXiv:1302.7025 Journal information: arXiv Social network sites work based on the concept of one person sending a friend request to another. If the request is accepted, the two become “friends” which means they gain access to each other’s privately posted information. Quite often, one person wishes to become “friends” with someone else on the network that they don’t know—a celebrity perhaps, or a person of influence in business. Sending a friend request to such a person generally fails, however, because the person getting the request doesn’t have any reason to accept. Celebrities rarely if ever accept friend requests from people they don’t know, for example, if they did, their friend list would become unmanageable, not to mention useless—the idea behind a friend list is to keep in touch with friends, after all.But still, sometimes it would be beneficial to somehow manipulate a stranger into accepting a friend request by fooling them into believing that there are mutual acquaintances. Unfortunately, social networks don’t offer a way to make that happen. In this new effort, the research team has devised a way to do it, by creating an algorithm that offers the names of people to friend to create an eventual pathway to the intended target. As more and more of these friends accept friend requests, (because they appear to be in the same social circle), it becomes more and more likely that the actual intended target will accept a friend request as it appears to them that they and the requester have many common friends, and thus exist in the same social circle.There is one caveat here, and that is the algorithm only works if implemented by the social network itself because they are the only ones that can analyze the structure of friend relationships between different individuals who don’t know each other or have any friends in common. There is also the problem of figuring out why a social network such as Facebook would ever possibly want to add such a feature. It would seem contrary to their most basic philosophy—to allow “friends” to keep in touch. Explore further Citation: Researchers develop algorithm to maximize friendship acceptance by strangers on social networks (2013, March 6) retrieved 18 August 2019 from https://phys.org/news/2013-03-algorithm-maximize-friendship-strangers-social.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.center_img (Phys.org) —A small team of computer scientists from Taiwan, the U.S. and China has developed an algorithm that aids a desire to manipulate an unknown social network user into accepting a friend request. The idea, as they describe in their paper they’ve uploaded to the preprint server arXiv, is to offer intelligent suggestions of other people to friend to create a mutual social circle of friends, which will increase the odds of the ultimate target agreeing to a friend request. © 2013 Phys.org How well do you know your friends? More information: Maximizing Acceptance Probability for Active Friending in On-Line Social Networks, arXiv:1302.7025 [cs.SI] arxiv.org/abs/1302.7025AbstractFriending recommendation has successfully contributed to the explosive growth of on-line social networks. Most friending recommendation services today aim to support passive friending, where a user passively selects friending targets from the recommended candidates. In this paper, we advocate recommendation support for active friending, where a user actively specifies a friending target. To the best of our knowledge, a recommendation designed to provide guidance for a user to systematically approach his friending target, has not been explored in existing on-line social networking services. To maximize the probability that the friending target would accept an invitation from the user, we formulate a new optimization problem, namely, emph{Acceptance Probability Maximization (APM)}, and develop a polynomial time algorithm, called emph{Selective Invitation with Tree and In-Node Aggregation (SITINA)}, to find the optimal solution. We implement an active friending service with SITINA in Facebook to validate our idea. Our user study and experimental results manifest that SITINA outperforms manual selection and the baseline approach in solution quality efficiently.via Arxiv Bloglast_img read more

Read More

Researchers build selfassembling multicopter distributed flight array w Video

31 August 0

first_img The point of the craft is to help students learn to understand distributed networks using a hands-on approach. To date, the team at ETH has built two such devices with two different means of communication, but the basic configuration remains the same. A number of individual copters, each shaped like a hexagon, roll around on a flat surface and eventually hook up in a random fashion with some or all of the others in the vicinity. After a moment of communication, each of the copters starts its rotor and the craft rises into the air and hovers, maintaining its balance. After another moment, the individual copters stop their rotors and the craft falls to the ground, breaking apart into individual copters again. Thus far the research group, which is made up of professors and students, acknowledges that the DFA doesn’t really serve any purpose other than as a teaching aid, but it does hold a certain beauty as the individual bots work together to achieve what none of them can alone.Each individual copter has inertial sensors that monitor tilt and roll and a processor that converts the sensor data to spin speed of its rotor. By itself, it’s incapable of flight—torque causes it to crash immediately upon takeoff. To offset torque, half of the copters in the multi-copter craft spin their rotors in the opposite direction of the other half. QFO Labs wants to send palm-sized copters out to play Researchers at ETH Zurich, a technical University in Switzerland, have developed a unique type of copter. It’s made of several single rotor craft that physically connect to one another autonomously to create a larger multiple rotor craft. Because the craft is self-assembled, each time it takes flight, it has a different configuration. The researchers call their craft a Distributed Flight Array (DFA). One test unit has the individual copters communicating via infrared signaling, the other through metal pins on the sides of bots. Also, one group has latches to allow the copters to physically connect to one another, the other magnets. Both configurations rely on a distributed network to operate, which means that there is no central control. Each of the copters monitors itself and makes adjustments as it sees fit. The end result is a multi-configuration craft that is able to lift itself off the ground and hover (keeping itself level) in the air and then return to Earth, with very minimal input (joystick control to keep the craft from wandering away) from its human operators. More information: www.idsc.ethz.ch/Research_DAndrea/DFA Explore furthercenter_img While the DFA itself might not be commercialized, concepts learned by students who helped create it will almost certainly be applied some day, helping to create multifaceted robots carrying out yet to be imagined missions. © 2013 Phys.org Citation: Researchers build self-assembling multi-copter distributed flight array (w/ Video) (2013, July 23) retrieved 18 August 2019 from https://phys.org/news/2013-07-self-assembling-multi-copter-flight-array-video.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.last_img read more

Read More

Assessing scientific research by citation wake detects Nobel laureates papers

31 August 0

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. In their study, the researchers analyzed all papers in the Physical Review database, dating back more than a century. In their method, each paper receives a wake citation score. A paper’s wake consists of all papers that that have cited it, either directly or indirectly. Since a paper can receive citations only from papers published at a later date, these papers form a “wake” of that paper as viewed on a graph. All papers in a paper’s wake are then assigned to neighborhood layers according to the length of the shortest path to the paper (similar to the concept of degrees of separation). In terms of idea propagation, the shortest path can also be viewed as the minimal number of processing steps of an idea. Finally, the paper’s wake citation score is computed as a weighted sum of the total number of papers in each layer. A detrending factor accounts for the fact that, the earlier a paper is published, the more papers there are in the future that could potentially cite it. A dilution factor can also be applied to restrict the number of layers considered, from only direct citations to the full wake of citations.The resulting wake citation scores yield a ranking of papers that is very different than a list of papers ranked by number of citations. As the results show, 9 out of the top 10 papers ranked by wake citation score are only moderately cited (the exception is the #1 ranked paper, “Theory of Superconductivity” by Bardeen, Cooper, and Schrieffer). The other papers show a very high ratio between the direct-citation-rank and the wake-citation-rank. For example, the paper ranked #2 according to wake citation score (“The Radiation Theories of Tomonaga, Schwinger, and Feynman” by F. Dyson) has a ratio of 707.5, indicating a direct-citation-rank of merely 1,415. Among the top 100 papers ranked by wake citation score, 86 show a ratio higher than 10.As for which ranking method is “better,” there is of course no objective measure of importance; otherwise, that would be the only measure needed. But considering the widely accepted scientific quality of Nobel Prize research, Klosik and Bornholdt have checked their top-ranked papers that have been coauthored by Nobel Prize laureates. They found that 18 of the top 25 and more than half of the top 100 papers have contributions from a Nobel Prize laureate. In contrast, the ranking by direct citation count yields Nobel author contributions in just 4 of the top 25 and 25 of the top 100 papers. (Overall, the ranking by direct citation in the Physical Review database is dominated by papers on density-functional theory.)Besides comparing to the direct citation ranking, the researchers also compared the wake citation ranking to one of the more elaborate measures of rank, which is Google’s PageRank algorithm. They found that the top papers according to PageRank contain more Nobel laureate coauthors than in the direct citation rank, but fewer than in the wake citation rank. One of the biggest differences between PageRank and wake citation is that PageRank counts weighted paths (the connections between papers) while wake citation counts weighted nodes (the papers themselves). While the wake citation method currently applies only to papers, Klosik and Bornholdt plan to extend the measure to scientists in the future.”We are currently exploring the wake citation score as an impact measure for scientists,” Bornholdt said. “This could provide a more balanced ranking of scientists from different fields.” The 10 top-ranked publications according to the wake citation score with dilution parameter chosen to be 0.9 (where 1.0 means the whole wake is considered). Nobel Prize laureates are labelled with an asterisk. The second column shows the fraction of the ranks assigned to the paper according to the number of direct citations and the wake citation score, respectively. Credit: © Klosik, Bornholdt (CC by 4.0) Journal information: PLoS ONE International collaborations produce more influential science, analysis finds (Phys.org)—Ranking scientific papers in order of importance is an inherently subjective task, yet that doesn’t keep researchers from trying to develop quantitative assessments. In a new paper, scientists have proposed a new measure of assessment that is based on the “citation wake” of a paper, which encompasses the direct citations and weighted indirect citations received by the paper. The new method attempts to focus on the propagation of ideas rather than credit distribution, and succeeds by at least one significant measure: a large fraction (72%) of its top-ranked papers are coauthored by Nobel Prize laureates. “Our wake citation score is less sensitive to the size of the research community of a paper than other existing measures, as we do not focus on the direct citation count of a paper,” Bornholdt told Phys.org. “What makes our wake citation score unique is our focus on whether a paper ‘started something,’ by estimating its ‘word of mouth dynamics’ from the subsequent citation network.” Ph.D. student David F. Klosik and Dr. Stefan Bornholdt at the University of Bremen have published their paper on the citation wake measure of publications in a recent issue of PLOS ONE.As Klosik and Bornholdt explain, scientists’ practice of citing the work that influenced them in the reference list of their own publications offers a wealth of data on the structure and progress of science. The difficulty lies in interpreting the data, which is often a controversial process. The first paper citation network was developed in the 1960s, and early analysis was based almost exclusively on counting a paper’s number of direct citations. This method has formed the basis of several newer quantitative methods of assessment, such as the h-index, which attempts to measure the impact of individual researchers, and the Thomson Scientific Journal Impact Factor, which ranks the relative importance of journals. However, it’s well-known that measures based on citation count have several shortcomings. For one thing, a paper’s ranking strongly depends on the citation habits and size of the paper’s field. Further, newer papers have fewer citations simply because they have not been around long enough to receive as many citations as older papers. On the other hand, the citation count may underestimate the impact of very old yet groundbreaking publications, since once seminal results become textbook knowledge, the original papers are often no longer cited. More recently, newer methods (such as CiteRank, SARA, and Eigenfactor) have addressed some of these drawbacks by accounting for factors other than direct citations. While they have made improvements, these methods generally view the citation network primarily as one of credit diffusion.Klosik and Bornholdt’s new measure differs in that it views the citation network as a picture of idea propagation, in which the ideas within a paper influence future research far beyond the citations the paper receives directly. © 2014 Phys.org The wake scores of all papers in the Physical Review citation base from 1892 to 2009. The dashed line shows the maximal wake size at a given publication date. The “ridge” formed by the data indicates cross-references between scientific subfields. Credit: © Klosik, Bornholdt (CC by 4.0) Explore further More information: David F. Klosik and Stefan Bornholdt. “The Citation Wake of Publications Detects Nobel Laureates’ Papers.” PLOS ONE. DOI: 10.1371/journal.pone.0113184 Citation: Assessing scientific research by ‘citation wake’ detects Nobel laureates’ papers (2014, December 12) retrieved 18 August 2019 from https://phys.org/news/2014-12-scientific-citation-nobel-laureates-papers.htmllast_img read more

Read More

Understanding reef systems at the genetic level

31 August 0

first_img More information: “The genome of Aiptasia, a sea anemone model for coral symbiosis.” PNAS 2015 ; published ahead of print August 31, 2015, DOI: 10.1073/pnas.1513318112AbstractThe most diverse marine ecosystems, coral reefs, depend upon a functional symbiosis between a cnidarian animal host (the coral) and intracellular photosynthetic dinoflagellate algae. The molecular and cellular mechanisms underlying this endosymbiosis are not well understood, in part because of the difficulties of experimental work with corals. The small sea anemone Aiptasia provides a tractable laboratory model for investigating these mechanisms. Here we report on the assembly and analysis of the Aiptasia genome, which will provide a foundation for future studies and has revealed several features that may be key to understanding the evolution and function of the endosymbiosis. These features include genomic rearrangements and taxonomically restricted genes that may be functionally related to the symbiosis, aspects of host dependence on alga-derived nutrients, a novel and expanded cnidarian-specific family of putative pattern-recognition receptors that might be involved in the animal–algal interactions, and extensive lineage-specific horizontal gene transfer. Extensive integration of genes of prokaryotic origin, including genes for antimicrobial peptides, presumably reflects an intimate association of the animal–algal pair also with its prokaryotic microbiome. 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: Understanding reef systems at the genetic level (2015, September 8) retrieved 18 August 2019 from https://phys.org/news/2015-09-reef-genetic.html Researchers have been seeking an experimentally versatile model of the cellular biology underlying this symbiosis, which could be a key to understanding the adaptability and resilience of reef systems. An international group of researchers now reports in the Proceedings of the National Academy of Sciences on a genetic study of the sea anemone Aiptasia, a globally distributed species that harbors Symbiodinium, the most widespread known group of endosymbiotic dinoflagellates, which inhabit many species and are common to cnidarians that occupy nutrient-poor waters.The host provides the algae with a sheltered environment and the nutrients necessary for photosynthesis and growth; in return, Symbiodinium supplies over 90 percent of the cnidarian’s total energy. The reasons this holobiont provides an attractive model system for reef studies include polyp sizes convenient for experimentation, and its easy production in a laboratory environment, where it can reproduce asexually, yielding large clonal populations. It can also be maintained indefinitely in an aposymbiotic state (without its endosymbiote) and reinfected with a variety of Symbiodium strains.The researchers sequenced the DNA from Aiptasia anemones and produced a reference transcriptome, which was sequenced using RNA derived from different developmental and symbiotic states. They uncovered a number of previously unknown genetic features of Aiptasia, but more importantly, the study provides a foundation for understanding the evolution and function of the symbiosis between the two organisms. Among their discoveries, the researchers found a novel cnidarian-specific family of putative pattern-recognition receptors that may be involved in the symbiotic relationship. Cnidarian hosts must necessarily distinguish among potential symbionts, and most can establish relationships with some strains of Symbiodinium but not with others. “Such discriminations must be accomplished in the absence of an adaptive immune system and presumably depend on innate immunity mechanisms that involve the recognition of microbial cell-surface molecules by host pattern-recognition receptors,” the authors write. The study’s findings support the hypothesis that invertebrate pattern-recognition capabilities are more flexible than previously assumed.They also document evidence for horizontal gene transfer (HGT) between the hosts and the symbiotic dinoflagellates. Given that the associations between the two organisms have evolved over millions of years, HGT is extremely likely to have occurred. The researchers found 275 HGT candidate genes specific to Aiptasia, plus another 548 candidates believed to have been transferred from a nonmetazoan source to a basal cnidarian in the evolutionary past and shared among a large number of cnidarians. The researchers conclude that the variety of conserved features found in their analysis should help to illuminate the evolution of many kinds of symbiotic anthozoans, not just Aiptasia-Symbiodinium holobionts, thus enhancing knowledge of reef systems, among the most important marine ecosystems. Journal information: Proceedings of the National Academy of Sciences (Phys.org)—Coral reefs are the most diverse marine ecosystems, biodiversity hotspots now under anthropogenic threat from climate change, ocean acidification and pollution. Efforts are underway to protect and expand shrinking reef systems, but such endeavors are inhibited by the lack of information about such fundamental features as the functional symbiosis between the cnidarian coral animal and the photosynthetic alga that live in its gastrodermal cells.center_img © 2015 Phys.org Aiptasia sp. Credit: Wikipedia/CC BY-SA 3.0 Caribbean coral findings may influence Barrier Reef studies Explore furtherlast_img read more

Read More

Physicists investigate erasing information at zero energy cost

31 August 0

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. Scientists show how to erase information without using energy Credit: CC0 Public Domain Scientists have only recently investigated these fluctuations in the context of the Landauer principle, where they found that these fluctuations are quickly suppressed by something called the Jarzynski equality. This means that heat energy fluctuations have only a very tiny probability of violating the Landauer principle. In the new study, the scientists have for the first time investigated the corresponding discrete fluctuations that arise when erasing information using spin.Among their results, the researchers found that the discrete fluctuations are suppressed even more quickly than predicted by the corresponding Jarzynski equality for “spinlabor”—a new term the scientists devised that means the spin equivalent of work. This is the first evidence of beating this bound in an information erasure context. The quick suppression means that the fluctuations have an extremely low probability of using less than the minimal cost required to erase information using spin, as given by the Vaccaro-Barnett bound, which is the spin equivalent of the Landauer principle.”Our work generalizes fluctuation relations for erasure using arbitrary conserved quantities and exposes the role of discreteness in the context of erasure,” Bedkihal told Phys.org. “We also obtained a probability of violation bound that is tighter than the corresponding Jarzynski bound. This is a statistically significant result.”The scientists also point out that this process of erasing information with spin has already been experimentally demonstrated, although it appears to have gone unnoticed. In spin-exchange optical pumping, light is used to excite electrons in an atom to a higher energy level. For the electrons to return to their lower energy level during the relaxation process, atoms and nuclei collide with each other and exchange spins. This entropy-decreasing process can be considered analogous to erasing information at a cost of spin exchange.Overall, the new results reveal insight into the thermodynamics of spin and could also guide the development of future applications. These could include new kinds of heat engines and information processing devices based on erasure that use inexpensive, locally available resources such as spin angular momentum. The researchers plan to further pursue these possibilities in the future. “The erasure mechanism can be used to design generalized heat engines operating under the reservoirs of multiple conserved quantities such as a thermal reservoir and a spin reservoir,” Bedkihal said. “For example, one may design heat engines using semiconductor quantum dot systems where lattice vibrations constitute a thermal reservoir and nuclear spins constitute a polarized spin reservoir. Such heat engines go beyond the traditional Carnot heat engine that operates under two thermal reservoirs.” Explore further Citation: Physicists investigate erasing information at zero energy cost (2017, February 22) retrieved 18 August 2019 from https://phys.org/news/2017-02-physicists-erasing-energy.html More information: Toshio Croucher, Salil Bedkihal, and Joan A. Vaccaro. “Discrete Fluctuations in Memory Erasure without Energy Cost.” Physical Review Letters. DOI: 10.1103/PhysRevLett.118.060602, Also at arXiv:1604.05795 [quant-ph] Investigating this idea further, physicists Toshio Croucher, Salil Bedkihal, and Joan A. Vaccaro at the Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland, Australia, have now discovered some interesting results about the tiny fluctuations in the spin cost of erasing information. The work could lead to the development of new types of heat engines and information processing devices.As the scientists explain in a new paper published in Physical Review Letters, the possibility that information can be erased at zero energy cost is surprising at first due to the fact that energy and entropy are so closely related in thermodynamics. In the context of information, information erasure corresponds to entropy erasure (or a decrease in entropy) and therefore requires a minimum amount of energy, which is determined by Landauer’s erasure principle.Since Landauer’s erasure principle is equivalent to the second law of thermodynamics, the zero-energy erasure scheme using arbitrary conserved quantities can be thought of as a generalized second law of thermodynamics. This idea dates back to at least 1957, when E. T. Jaynes proposed an alternative to the second law in which heat energy is thought of in a more general way than usual, so that heat incorporates other kinds of conserved quantities. Applying this framework to information erasure, in 2011 Vaccaro and Stephen Barnett showed that the energy cost of information erasure can be substituted with one or more different conserved quantities—specifically, spin angular momentum.One important difference between heat energy and spin angular momentum is that, while heat may or may not be quantized, spin angular momentum is an intrinsically quantum mechanical property, and so it is always quantized. This has implications when it comes to accounting for tiny fluctuations in these quantities that become significant when designing systems at the nanoscale. Journal information: Physical Review Letters © 2017 Phys.org (Phys.org)—A few years ago, physicists showed that it’s possible to erase information without using any energy, in contrast to the assumption at the time that erasing information must require energy. Instead, the scientists showed that the cost of erasure could be paid in terms of an arbitrary physical quantity such as spin angular momentum—suggesting that heat energy is not the only conserved quantity in thermodynamics.last_img read more

Read More

Surgeon General Sounds Alarm On Risk Of Mariju

31 August 0

first_imgSurgeon General Sounds Alarm On Risk Of Marijuana Addiction… Jane Khomi by NPR News Allison Aubrey 8.29.19 2:01pm At a time when more than 30 states and the District of Columbia have legalized the use of marijuana for either medical or recreational use, the U.S. surgeon general says no amount of the drug is safe for teens, young adults and pregnant women.”While the perceived harm of marijuana is decreasing, the scary truth is that the actual potential for harm is increasing,” Surgeon General Jerome Adams said Thursday during a press conference to announce the new advisory.Surveys show that an increasing number of adolescents and pregnant women use the drug, which can be eaten, smoked or vaped. But the surgeon general told NPR in an interview that many people are not aware of just how potent the drug can be.”This is not your mother’s marijuana,” he said. The THC concentration in marijuana plants has increased threefold between 1995 and 2014, according to the report, and concentrated products can contain up to 75% THC.”The higher the THC delivery, the higher the risk,” Adams said.Young people who regularly use marijuana are “more likely to show a decline in IQ and school performance [and] are more apt to miss classes,” Adams said. And frequent use of the drug can also impair a child’s attention, memory and decision-making.In addition, it can be habit-forming. “Nearly 1 in 5 people who begin marijuana use during adolescence become addicted,” Adams said. “That’s scary to me as the dad of a 15-, a 13- and a 9-year-old.”Symptoms of marijuana dependency include “irritability, mood and sleep difficulties, decreased appetite, cravings, restlessness, and/or various forms of physical discomfort that peak within the first week after quitting and last up to 2 weeks,” according to the National Institute on Drug Abuse. And marijuana becomes addictive “when the person cannot stop using the drug even though it interferes with many aspects of his or her life,” according to NIDA.Health and Human Services Secretary Alex Azar announced that President Trump is donating part of his salary this quarter — about $100,000 — to fund a digital media campaign to bring attention to the risks of marijuana use.There’s still a lot that’s unknown about the risks of marijuana, and federal officials say they support more local and federal research. Just this week, the Drug Enforcement Administration said it would start to process pending applications for permission to cultivate the plant for research, as NPR reported. The Trump administration is not the first to sound the alarm about the rising use of marijuana. At a time when surveys point to a significant increase in the number of pregnant women using the drug, the American College of Obstetricians and Gynecologists is educating women about the risks. “Marijuana and pregnancy don’t mix,” the group urges. The organization published an infographic that points to the range of risks for women and their fetuses, including disruption of brain development, smaller birth weight, higher risk of premature birth, and behavioral problems in childhood.Bottom line, the surgeon general wants to remind people that despite what’s happening in states, federal law hasn’t changed. And there is good reason for caution.Copyright 2019 NPR. To see more, visit NPR.last_img read more

Read More

Celebrating the art of photography

31 August 0

first_imgBeginning from 5 March, the festival incorporates eight cities which includes Delhi, Mumbai, Ahmadabad, Bangalore, Hyderabad, Goa, Kolkata and Trivandrum. Aimed at showcasing the multi-faceted nature of French culture through unique Indo-French co-productions, the festival will be held for a month.The festival endeavours to reach out to the audience by taking photography out of traditional spaces such as museums and galleries and showcase them in public spaces to change the relationship between people and their city. Delhi will witness Connaught Place being transformed into an art gallery with life size projections on the facades of inner circle, along with magical projections at the bus stops, subways to increase social inclusion. The idea is to explore all avenues to bring together amateur and professional photographers and photography enthusiasts. Also Read – ‘Playing Jojo was emotionally exhausting’Some highlights will include a mobile photo booth that will be showcased in Delhi TBC where Anay Mann, an expert photographer, will use backdrops of famous French places and venues. Other attractions of the festival will include the water screen image projections, a unique music tribute to India, photography exhibitions across several themes like urban living and Pablo Bartholomew’s World of Indian Cinema.WHEN: 5 March onwardsWHERE: Around Connaught Placelast_img read more

Read More

Fakir of the French opera

31 August 0

first_imgInternationally-acclaimed SAMUDRA dance group performed a Ballet Segment in an excerpt from the French opera The Fakir of Benares, presented as part of the 10th anniversary celebrations of The Neemrana Music Foundation, on December 5 and 6, at the Jawaharlal Nehru Stadium in New Delhi.The Foundation’s anniversary gala, co-presented by the European Union, celebrates a decade of opera in India. The Fakir of Benares (2003) was the first opera ever performed in Delhi. Samudra performed a segment of the opera at the time and they have been invited again to be a part of it. Also Read – ‘Playing Jojo was emotionally exhausting’Madhu Gopinath and Vakkom Sajeev, the incredibly brilliant Choreographers, Directors and Principal Dancers of Samudra who have performed  in 48 countries – which includes an applause-winning performance at  The Royal Opera House, London, are going to present a  mesmerising show  at the Neemrana Festival. They also choreographed sequences for the opening and closing ceremonies of The 2010 Commonwealth Games in New Delhi.Madhu and Sajeev founded Samudra in 1998 and have since been training dancers in the new style and touring the world with their original choreographic productions. Also Read – Leslie doing new comedy special with NetflixA French opera by playwright Leo Manuel, The Fakir of Benares, was a massive hit when it was first staged in Paris in 1922. The opera’s exotic Indian milieu, the grandiose sets and costumes, the beautiful music and powerful performances made it one of the most successful shows of its time.But the glory of the opera lasted only a short while, as a massive fire destroyed most of the costumes and sets, and the complete score was lost during the Second World War. The opera was largely forgotten until 2002, when Priya Wacziarg, a soprano, came upon the score of the opera in a bookshop in Paris. It took them a while to put together an orchestra and a choir. In 2003, the first production of The Fakir of Benares in 80 years was ready for the stage. Famous director Muzaffar Ali undertook to do the stage direction, after a French conductor recomposed the missing orchestral parts. Muzaffar Ali lent the quintessentially French opera a genuine Indian touch by incorporating two ballets rooted in Indian classical dance. Samudra, was chosen to perform one of these.The Neemrana Music Foundation, established in New Delhi by Priya’s father, the late Francis Wacziarg, has produced nine operas over a decade.last_img read more

Read More

Bengal seeks additional forces from other states for Panchayat polls

31 August 0

first_imgKolkata: Four or five other neighbouring states have been contacted for additional forces to be deployed at all the polling premises for the state Panchayat polls on May 14, state Director General of Police Surajit Kar Purkayastha said on Friday.He claimed that the state has made adequate security arrangements for conducting the rural polls in a single phase. Purkayastha held a press conference at Nabanna on Friday where he stated that elections should be allowed to take place peacefully. He appealed to everyone and sought their cooperation regarding the same. Also Read – Heavy rain hits traffic, flights”The security arrangements for the Panchayat polls are adequate. There will be armed coverage in all the polling premises,” Purkayastha told reporters here.Stating that the state police are having sufficient capacity, Purkayatha said: “Manpower in the state police has gone up and the strength of the police has also increased.”It may be mentioned that there are 58,467 booths in 43,067 polling premises in 20 districts across the state and all the premises will be brought under the coverage of the armed forces. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe Calcutta High Court sought a detailed report on security arrangements for poll personnel. The court directed Anuj Sharma ADG (Law and Order) to submit the report by May 4.A PIL has been filed with the High Court demanding compensation of Rs 10 lakh in case of death of a poll personnel and Rs 5 lakh for getting injured. In this connection, the court also wanted to know the steps that have been taken for the security of the polling personnel. The state in this connection submitted that they are taking all necessary steps for security of the polling personnel. The court has given directions to give it in writing. Meanwhile, the State Election Commission (SEC) convened a meeting of 10 political parties to discuss the poll process. The Calcutta High Court had also directed the SEC to conduct the elections after holding discussions with all the stakeholders.On Thursday, the State Election Commission announced the poll date stating that the election will be held on a single day (May 14) and the post-poll scrutiny will be held on May 15 and if needed, repolling will be conducted on May 16. Though the date for counting of votes is yet to be announced, the state government has written to the SEC urging to do the same on May 17.The state government has declared a holiday in 20 districts on May 13, 14 and 15 where the elections will be held.The elections were earlier slated to be held in three phases on May 1, 3 and 5 but the schedule was pushed back after the Calcutta High Court stayed the polling process on petitions moved by the Opposition parties, who complained that they were not allowed to file nominations allegedly by armed miscreants owing allegiance to the ruling Trinamool Congress.last_img read more

Read More
Lakhvi case subjudice no need to jump the gun

Lakhvi case subjudice no need to jump the gun

31 August 0

first_imgPakistan on Monday said India should “not jump the gun” as the case related to Mumbai terror attack mastermind Zakiur Rehman Lakhvi is “sub-judice”.India had conveyed its outrage after a court in Islamabad had earlier this month ordered release of Lashkar terrorist Lakhvi, who is responsible for 26/11 terror attacks in Mumbai, though he was later detained again for 30 days. “The case is sub-judice. So let’s wait. Better not jump the gun,” Pakistani High Commissioner Abdul Basit told reporters here on the sidelines of a function.Lakhvi and six others have been charged with planning and executing the 2008 Mumbai attack that left 166 people dead, including several foreigners. On March 14 in Islamabad, Pakistan had detained Lakhvi for 30 more days under a public security order before he could be released from jail following a court directive to set him free.last_img read more

Read More

Firhad Hakim stresses on steps to check vectorborne diseases

31 August 0

first_imgKolkata: State Municipal Affairs minister Firhad Hakim laid emphasis on public awareness to successfully fight against vector-borne diseases like dengue while addressing a meeting on Saturday. “Councillors will have to pull up their socks for massive public awareness in their respective municipal areas to combat diseases like dengue,” Hakim said speaking at a meeting of urban local bodies and 25 municipalities across the state.The minister maintained that despite all efforts on part of the Also Read – Heavy rain hits traffic, flightsstate government and other stakeholders, the desired results over vector-borne diseases cannot be achieved until people are responsible enough to keep their own premises clean. “We are using fogging machines, doing house-to-house campaigns and circulating do’s and don’t’s but people have to be vigilant,” the minister said.He also referred to one of his own experiences when he had found that water had accumulated in flower pots on the roofs of his own house. “I had gone to the roof of the house a few days back while it was raining. I found there were some empty flower pots in which water was accumulating. I immediately turned them upside down and told my family members that they should be careful and should not let these things happen,” he added. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe minister had urged the chairman of the civic bodies to conduct fortnightly meetings to monitor the progress of the awareness drives in their respective areas.Some chairmans flagged off the issue regarding the resistance that they often face in conducting drives at the Central government establishments and the surrounding areas of ponds owned by public. “We have been given contact numbers of nodal officers whom we need to get in touch with whenever we face any difficulty in taking such drive. If the problem continues even after contacting the nodal officers, then the department should be informed,” a chairman of a municipality in the northern fringes of the city said.last_img read more

Read More

78yearold iconic Elite Cinema of Kolkata closed forever

31 August 0

first_imgKolkata: Once owned by 20th Century Fox, the iconic Elite Cinema here has joined the list of single screens dropping curtains forever, unable to cope with competition in an era of multiplexes and the internet. The 78-year old auditorium in central Kolkata ended its journey with a notice pasted at the entrance that announced “permanent and irrevocable closure” with effect from June 1.Manager Shambhukumar Batabyal admitted that the owners have been incurring huge losses. Also Read – Heavy rain hits traffic, flights”We have 1,228 seats…. the average of seat occupancy throughout the year is just 1-2 per cent, which makes it difficult for us to run it,” he said. An IANS correspondent on Wednesday found the gates of Elite Cinema locked with none of its employees seen in the vicinity.Located in the bustling Dharamsala area, the hall till a few years back was a popular draw among the youth as also families. It boasts of an enviable guest list including the likes of Raj Kapoor, Amitabh Bachchan and Shahrukh Khan. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedWith the advent of multiplexes and fast internet, Elite cinema, like most other single screens, had lost its sheen.”It pulled huge crowds in the past, but the struggle began since last five years. Everyone now visits a multiplex in a mall or streams videos on their mobile,” said Tarachand, the owner of an adjoining betel shop running for almost 60 years.Elite Cinema was opened on August 2, 1940 and was thronged by the ‘elite’ of erstwhile Calcutta, but on May 31 it ended its last show silently owing to the lack of audience. The notice mentions that the management is unable to run the theatre due to heavy losses and debts. All the terminated employees have been asked to collect all their legal dues.Elite Cinema was once owned by 20th Century Fox and famous photographic studio Bourne & Shepherd. Classics like “Gone with the Wind”, “Sound of Music” and “My Fair Lady” had been screened here successfully for the audience.Old timers still recall the mammoth queues during the screening of Amitabh Bachchan-starrer “Shahenshah”.The cinema hall also had a bar attached which managed to attract a few footfalls. It was also closed in the month of March.”The bar still managed to bring some business but with its closure on March 31, that also started diminishing,” said the betel shop owner.Previously, many other halls in the city have ended their show. Metro, Grace, Ujjwala, Orient, Purna have become a part of history.last_img read more

Read More

Lead exposure hampers childrens sleep quality

31 August 0

first_imgLead exposure in early in life is associated with increased risk of sleep problems and excessive daytime sleepiness in later childhood, says a new study.“Little is known about the impact of heavy metals exposure on children’s sleep, but the study’s findings highlight that environmental toxins – such as lead – are important pediatric risk factors for sleep disturbance,” said the study’s principal investigator Jianghong Liu, associate professor at University of Pennsylvania School of Nursing. “Lead exposure is preventable and treatable, but if left unchecked can result in irreversible neurological damage,” Liu noted. Lead can be found in many products and locations including some candies, toys, and traditional medicines.The research is based on data from a study, involving more than 1,400 Chinese children, that began in 2004 investigating the influence of lead exposure in relation to the development of children and adolescents’ neurocognitive, behavioural and health outcomes. Using the data from the cohort study, 665 children’s blood lead levels were assessed when they were between three and five years old, and sleep was assessed six years later, when the children were between nine and eleven years old. Child-reported insomnia and use of sleeping pills were two times and three times more prevalent in children with blood lead levels (BLL) greater than or equal to 10 ug/dL (microgram/decilitre) than in children with BLL less than 10 ug/dL. Lead pollution is pervasive throughout China and other developing countries, and though rates of lead exposure are decreasing due to the phase-out of leaded gasoline and increased public awareness, its persistence presents a significant health risk to children, the researchers said. The findings will be published in an upcoming issue of the journal Sleep.last_img read more

Read More

History comes alive

31 August 0

first_imgFinale of 125th Foundation Year Celebrations of National Archives of India (NAI), organised by Ministry of Culture had commenced on March 7, in the national Capital. The celebrations, which will go on for a week, will culminate on March 11.N K Sinha, Secretary, Ministry of Culture inaugurated an Archival exhibition titled ‘Independent India: A Forward March (based on post Independence Public Records)’ in the premises of National Archives of India. Also Read – ‘Playing Jojo was emotionally exhausting’A two-day seminar on the ‘Sources of 18th and 19th Century’ is also being held from March 8-9 in the Conference Hall, NAI, Janpath.On the eve of ‘National Archives of India Foundation Day 2016’ on March 10, Prof. Surendra Gopal, an eminent historian will deliver the Foundation Day lecture on ‘Some Foreign Archives and India’s History’ in the auditorium of Nehru Memorial Museum and Library. The Finale of 125th Foundation Year would be culminated by following programmes in the presence of Dr Mahesh Sharma, Minister of State (I/C) for Culture and Tourism and Minister of State for Civil Aviation on March 11 in the auditorium of Nehru Memorial Museum and Library, Teen Murti Bhawan.Apart from this, a cultural programme, ‘Char Bait’ by the artists from Bhopal and Rampur Gharana, will also be organised in the lawns of National Archives of India on March 11.last_img read more

Read More

ER train services affected on day two of nationwide strike

31 August 0

first_imgKolkata: Train services in Eastern Railway zone were disrupted Wednesday after supporters of the two-day nationwide strike resorted to blockades at many places. The two-day nationwide strike, on January 8 and 9, was called by central trade unions to protest against ‘anti-people’ policies of the Centre. An Eastern Railway spokesman said that a suspected bomb was found on the railway tracks at Ashoknagar in Sealdah-Bongaon section that led to suspension of train services in the route. Also Read – 3 injured, flight, train services hit as rains lash Bengal The suspected country-made bomb, which was found near a level crossing at Ashoknagar, was removed by the civil authorities and train services resumed in the section at 10.25 am, the spokesman said. Banana leaves thrown on overhead wires at different places in the Sealdah South section led to disruption in train services in Sealdah-Diamond Harbour, Sealdah-Lakshmikantapur and Sealdah-Namkhana routes from 5.20 am. Barring the Sealdah-Diamond Harbour route, normal services were restored in the other two routes by 8.15 am. In the Howrah division of Eastern Railway, services were affected in the Bandel-Katwa route after agitators blocked tracks at Bhandartikuri station. Train services in the South Eastern Railway zone was normal, its spokesperson said.last_img read more

Read More

Kenyans steal the show at Darjeeling half marathon

31 August 0

first_imgDarjeeling: Kenyans ruled in the Darjeeling Police Marathon. Both the first prizes in the men’s and women’s categories were bagged by the Kenyans.The Darjeeling police organizes a half marathon every year to commemorate the birth anniversary of Swami Vivekananda. This year it was the 6th edition. The 21 km marathon starts from Sukhipokhari and ends at Darjeeling Chowrasta via Darjeeling Zoo. The men’s general category award was won by Noah Kemey and the women’s by Christine Kambua Muyana. The 30-year-old, Kemey, completed the 21 km in 1 hour 8 minutes and 42 seconds beating Shankar Man Thapa of 1/5 Gorkha Rifles, Siliguri, who completed the marathon in 1 hour 9 minutes and 38 seconds. Also Read – 3 injured, flight, train services hit as rains lash BengalThe 27-year-old Christina Kambua Muyanga completed the stretch in 1 hour 23 minutes and 48 seconds beating Kiranjeet Kaur of BSF, Punjab, who completed the marathon in 1 hour 25 minutes 10 seconds. The first prize included a cheque of Rs1 lakh 50 thousand, second prize Rs 75,000 and third Rs 50,000 for the general categories. There were special categories including local participants; police and civic volunteers. Prabal Chettri from Kalimpong bagged the first prize of Rs. 25,000 in the local category. Manas Das from Kolkata Police also won Rs. 25,000 in the police category. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedThe Terrain did not pose much challenge to the Kenyan runners but the biting cold did. “The terrain of the marathon route is quite as same in Kenya but it was very cold which caused a bit of problem,” stated Kemey. This was his first marathon in India. Prior to this, he participated in marathons in Netherlands, France, Italy, Germany and Brazil. Cristina found the competitors strong. “I faced stiff competition,” she added. This is her second marathon in India and the first in Darjeeling. Braving the morning chill, thousands lined up along the route to cheer up the runners. “There were more than 3,000 participants this time. This marathon is definitely growing important. There were many African runners. We will definitely raise the bar from the next edition,” stated Akhilesh Chaturvedi, Superintendent of Police, Darjeeling. There were cultural shows as well. Ace runner Jinson Johnson and Swastima Khadka, a popular actress from Nepal, were present at the event. “Hill people have good physical endurance and are natural runners. Parents should encourage their wards to take up sports if they are interested. However, there should be adequate infrastructure like trainers and gyms to produce good sportsmen,” stated Johnson, the Asian Gold medalist.last_img read more

Read More

Artificial sweeteners may up obesity heart disease risk

31 August 0

first_imgWorried about your ever increasing waistline? Cut down the use of artificial sweeteners as they may be associated with long-term weight gain and increased risk of obesity, a study has warned. Artificial sweeteners are substitutes for sugar that provides a sweet taste like that of sugar while containing significantly less food energy. The findings showed that artificial sweeteners or non-nutritive sweeteners may have negative effects on metabolism, gut bacteria and appetite. Thus, individuals consuming artificial sweeteners, such as aspartame, sucralose and stevia, may also be at risk of developing high blood pressure and heart disease, the researchers from University of Manitoba in Canada, said. Also Read – Add new books to your shelfAccording to researchers, the use of artificial sweeteners which is widespread and increasing is linked with the current epidemic of obesity and related diseases.For the study, published in CMAJ (Canadian Medical Association Journal), the team conducted a randomised controlled trials involving 1,003 people followed for six months on average.The trials did not show a consistent effect of artificial sweeteners on weight loss, and the longer observational studies showed a link between consumption of artificial sweeteners and relatively higher risks of weight gain and obesity, high blood pressure, diabetes, heart disease and other health issues.”We found that data from clinical trials do not clearly support the intended benefits of artificial sweeteners for weight management,” said Ryan Zarychanski, assistant professor at the University of Manitoba. “Caution is warranted until the long-term health effects of artificial sweeteners are fully characterised,” added Meghan Azad, assistant professor, at the University.last_img read more

Read More

Mamata releases TMC list for all 42 WB seats alleges attempt to

31 August 0

first_imgKolkata: West Bengal Chief Minister Mamata Banerjee Tuesday announced a list of TMC candidates for all the 42 Lok Sabha seats of the state, dropping 10 sitting MPs. She also attacked the BJP and the Modi government, claiming she had information that “VVIPs” were using helicopters and chartered flights to transport money to bribe voters. Releasing the list, the West Bengal leader assailed the Centre over a host of issues including the Rafale deal,farm distress and shrinking employment opportunities. Banerjee, also the TMC supremo, said the outgoing TMC lawmakers whose names do not figure in the list will be drafted for party work. She said 41 per cent of the nominees in the list are women. The TMC, she said, will also contest some seats in Odisha, Assam, Jharkhand, Bihar and the Andamans.last_img read more

Read More

How to be chic not flashy

31 August 0

first_imgWith the need to impress, women are looking to try newer trends and style statements. In such situations, one easily becomes the victim of flashy dressing. However one can take care of few basic guidelines to avoid such fashion faux paus. Experts lists down some steps: Nothing can kill your style quite as quickly as an ill-fitted shirt or too-tight pants. Even if the clothes feel comfortable, if they don’t fit, don’t wear them. Mix a print with something tonal or solid colours for a winning combo and not with another eye-catching print. Also Read – Add new books to your shelfThere are many things in life that would classify as being a drag, but your pants shouldn’t be one of them. Hem lines that flirt with the floor are fine when flared and flowy trousers are trending so much, but you’ve gone too far when they make contact with the floor. You wouldn’t leave the house in mud-covered clothes, so why would you walk outside with dirty shoes? A pair of less-than-clean kicks can ruin your outfit faster than you can click your heels together. Also Read – Over 2 hours screen time daily will make your kids impulsiveThere are some great boyfriend blazers in the market these days, but you can’t literally lift a boyfriend’s jacket and expect to look chic. What the designers call a “boyfriend blazer” is actually cut to strike a very feminine figure. No matter how romantic you think it is to snuggle in your boyfriend’s clothes, doing so likely gives you a sloppy appearance. If you’re going to venture into the fishnet trend, you’ll want to choose pieces with simple, solid fabrics and ensure that the pattern of the fishnet tights will stand out – otherwise things will get muddled, and you’ll end up looking like a hot mess! If you’re not sure where to begin, the easiest way is to opt for a statement accessory with shine: a pair of glittery pumps in gold or silver or a sparkly clutch will add that magic touch to your Little black dress. As metallics continue to reign in 2019, a gown in a metallic shade such as rose gold is a classy and fashionable choice. Another option is to pair a metallic skirt with a neutral blouse. For that stop-and-stare reaction, a fitted sequinned dress or gown is the way to go. Make sure the finishing of the garment is immaculate, and that the quality of sequins used is good.last_img read more

Read More