Month: August 2019 Page 1 of 16

Machines making other machines new twist on selfreplication

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. Engineers at the Massachusetts Institute of Technology recently tackled a key challenge: how can a machine replicate properly if its components appear at random? Living cells face a similar problem when duplicating their DNA from randomly diffusing chemical components. To address this issue, the group fabricated a simple self replicating machine that dealt robustly with randomly available input components.The MIT design consists small robotic blocks which link to one another using actuated hooks. A specific ordered linkage of blocks makes up a correctly formed device. A large number of individual blocks sit on a low-friction air-table, which shakes to move them about randomly. Each block carries both sensors to identify blocks around it and a program specifying which blocks to attach to and which to ignore. Blocks which pair correctly by chance stick together, while incorrect pairs fail to stick. With appropriate rules, certain structures can catalyze the formation of equivalent structures out of the random blocks. Thus correct structures that initially appear by chance will duplicate exponentially in a positive feedback loop.A key requirement for this engineering approach (and indeed for living cells) is good error control. Living organisms, for example, utilize clever chemical and kinetic techniques for minimizing errors in their copying processes. Incorrectly incorporated blocks in the MIT setup are excised using a clever set of error detection and correction rules. The total rule set is surprisingly small, making this work a nice demonstration of self-replication in the face of environmental randomness. This work paves the way in principle for smart materials which can self assemble into structures of interest, with minimal assistance on the part of humans.by Joe Levine, Copyright 2005 PhysOrg.com Explore further Bees required to create an excellent blueberry cropcenter_img How can we best build self-replicating machines? The past few decades have witnessed self-replicating virtual automata, ranging from the benign Game of Life by Conway to malicious computer viruses. Self-replicating physical constructs are, however, currently both delicate and rare. The work of mathematicians such as John von Neumann and Roger Penrose, around the birth of automata theory in the middle of the past century, revealed no limits in principle to constructing such devices. The main obstacles appear to be the substantial engineering challenges. Citation: Machines making other machines: new twist on self-replication (2005, October 3) retrieved 18 August 2019 from https://phys.org/news/2005-10-machines-self-replication.htmllast_img read more

Google Has More Than Android On Its Platform

first_imgD-wave Quantum 2 (Image credit: D-Wave/M. Thom) Behind the scenes, in fact, Google has been working with a D-Wave quantum computer that seems to be able to spot images of cars from among 20,000 photos faster than any other Google computer. Though there are reports of skepticism among higher math experts that D-Wave really is a quantum computer, it’s clear that Google is going to be the first to use the quantumest computer available to its fullest capacity.Fast and accurate sorting capability is a must, and not just for Internet browsers. Think about the jobs of radiologists, for example, looking for a diseased cell or two in a mass of tissue. Or a baggage screener looking for a gun, a knife, or a bomb in someone’s carry-on bag. Recently published research on “visual attention,” prepared by Harvard professor Jeremy Wolfe, demonstrates that the more we [humans!] look for that “needle in a haystack,” the less likely it is that we will find it. Now, how does that make you feel when you take a mammogram or get on an airplane?But what if a quantum computer could detect the diseased cell? And not only that. What if that super computer could determine which antibody might kill that cell without harming the surrounding cells? Think about how much time that would save researchers in testing various drugs, and how much time it would save in getting approval for potential life-saving drugs. It’s highly likely that Google Venture’s recent investment into Adimab was made with a computer antibody identifier in mind. Adimab, a New Hampshire-based biotech company, has already developed a simulated human immune system, composed of engineered yeast cells, that produces antibodies in response to drug molecules. This process obviates the need for testing engineered mice, as well as other animal testing, and produces therapeutic outcomes in less than eight weeks. Antibody producing human yeast cells (Image credit: Adimab) 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. © 2010 PhysOrg.com Explore further (PhysOrg.com) — In the last several weeks, we’ve read a bit about how Google is getting restless just being the world’s largest search engine and a proud cloud computing parent. In fact, Googleland is growing by quantum leaps and bounds. More information: — Adimab www.adimab.com/index.html– Google Collaborates with D-Wave on Possible Quantum Image Search www.physorg.com/news180107947.html– Google demonstrates quantum computer image search www.newscientist.com/article/d … er-image-search.html– Google Pours “Incredible” Computing Power into Antibody Drug Discovery With Adimab www.xconomy.com/boston/2010/02 … ab/?single_page=true– Guns, Tumors And The Limits Of The Human Eye www.npr.org/templates/story/st … hp?storyId=122561355 Citation: Google Has More Than Android On Its Platform (2010, February 5) retrieved 18 August 2019 from https://phys.org/news/2010-02-google-android-platform.html Already having a leg up on other biotech firms with its proprietary technology, Adimab has attracted investments from Polaris Venture Partners, SV Life Sciences, OrbiMed Advisors, and Borealis Ventures. But Adimab COO Errik Anderson admitted that Google’s investment was not just financial. In an interview with Xconomy, Anderson said that “…it was clear that Google Ventures immediately understood our value proposition—that a prolific discovery platform can drive even greater productivity when integrated with advanced computational tools.”Some interesting times ahead for supercomputing and for Google; that’s for sure. Google Collaborates with D-Wave on Possible Quantum Image Searchlast_img read more

Alloptical quantum computation step 1 A controlledNOT photonic gate

first_img Fig. 2. The KLM CNOT gate. (A) The gate is constructed of two NS gates; the output is accepted only if the correct heralding signal is observed for each NS gate. Gray indicates the surface of the BS from which a sign change occurs upon reflection. (B) The KLM CNOT gate with simplified NS gate. (C) The same circuit as (B) but using polarization encoding and PPBSs. (D) The stable optical quantum circuit used here to implement the KLM CNOT gate using PPBSs and a displaced-Sagnac architecture. The target Mach-Zehnder interferometer (MZ), formed by BS11 and BS12 in Fig. 2B, can be conveniently incorporated into the state preparation and measurement, corresponding to a change of basis. The blue line indicates optical paths for vertically polarized components, and the red line indicates optical paths for horizontally polarized components. (c) PNAS, doi:10.1073/pnas.1018839108 More information: Realization of a Knill-Laflamme-Milburn controlled-NOT photonic quantum circuit combining effective optical nonlinearities, PNAS, Published online before print June 6, 2011, doi: 10.1073/pnas.1018839108 Citation: All-optical quantum computation, step 1: A controlled-NOT photonic gate (2011, June 24) retrieved 18 August 2019 from https://phys.org/news/2011-06-all-optical-quantum-controlled-not-photonic-gate.html However, there remains a critical problem with SPDC sources: the ever-present possibility that the source will emit more than one photon. Excess photons lead to significant errors, especially as the number of photons in a quantum circuit increases. For post-SPDC sources, single-photon sources using atoms embedded in a micro-optical cavity are the most advanced – but they typically require an ultra-high vacuum environment and may be difficult to operate continuously, making system integration difficult.To address these issues, Takeuchi says that solid state single-photon sources using nanoscale light emitters, like single quantum dots or nitrogen vacancy (NV) centers in diamonds, are promising candidates. In fact, the team is now studying devices using NVs coupled with microsphere resonators and tapered optical fibers. “When such single photon sources are developed, we can implement single photon sources and optical quantum circuits in a tiny photonic chip, which could be used not only for quantum communication but also quantum metrology, which allows us to realize sensitivity beyond the standard quantum limit.”Further down the road, Takeuchi’s team will focus on developing a photonic quantum chip in which single photon sources, photon detectors, and nonlinear sign shift gates (photonic switches) are all embedded in a chip to form a functional quantum circuit. “Such a quantum circuit will be a building block of quantum information systems,” he notes, “and will be useful in quantum metrology.”In terms of applications, says Takeuchi, “the primary near-term use will be in quantum measurement,” says Takeuchi. After that, he sees enhanced sensitivity using non-classical photonic states being useful in broad areas of science, from gravitational wave detection to cell biology. “I believe such an optical quantum circuit will be useful for nanochemistry, where the number of probe photons has to be very small.”In the future, he concludes, controlled generation of entangled photon states is a significant step towards entanglement swapping, quantum teleportation, quantum cryptography and scalable approaches towards photonics-based quantum computing. “Optical quantum circuits will of course be useful for long-distance quantum key distribution in quantum communication, simulation and computation.” (PhysOrg.com) — The often counterintuitive quantum world of superposition, entanglement, and tunneling can greatly enhance applications as diverse as communication, information processing, and precision measurement. At the same time, photons have the equally attractive properties of low noise, light speed transmission, and ease of manipulation using conventional optics. However, due to the probabilistic nature of single photons, the two have never been integrated into a single system – until now. Researchers have developed a stable architecture that, by instantiating a fundamental feature of the proposed KLM controlled-NOT (CNOT) gate, proposed a decade ago, as an element in a photonic quantum circuit, is expected to allow on-demand entanglement generation and purification through scalable quantum computation. Fig. 1. The KLM nonlinear sign-shift (NS) gate. (A) If the NS gate succeeds it is heralded; indicated conceptually by the light globe. (B) The original KLM NS gate is heralded by detection of a photon at the upper detector and no photon at the lower detector. Gray indicates the surface of the beam splitter (BS) from which a sign change occurs upon reflection. (C) A simplified KLM NS gate for which the heralding signal is detection of one photon. (c) PNAS, doi:10.1073/pnas.1018839108 Photonic quantum technologies could be only light years awaycenter_img Originally described by E. Knill, R. Laflamme and GJ Milburn (KLM) in 2001, a controlled-NOT (CNOT) gate flips the polarization state of the target photon conditional on the control photon being horizontally polarized (the logical 1 state). The gate is capable of generating maximally entangled two-qubit states, which together with one-qubit rotations provide a universal set of logic gates for quantum computation. This remained a theoretical design until Prof. Shigeki Takeuchi and lead researcher Asst. Prof. Ryo Okamoto at Hokkaido University’s Research Institute for Electronic Science and Osaka University’s Institute of Scientific and Industrial Research, with Prof. Jeremy O’Brien at University of Bristol’s Center for Quantum Photonics, and Assoc. Prof. Holger Hofmann at Hiroshima University’s Graduate School of Advanced Sciences of Matter developed and demonstrated their CNOT gate. It was a daunting task: The KLM-CNOT optical quantum circuit has faced a number of obstacles since being proposed in 2001, the two most challenging being the lack of heralding (indistinguishable) single photon sources and the difficulty of stabilizing nested multiple optical path interferometers. Moreover, heralding is critical: Even though photonic quantum controlled-NOT gates have been demonstrated, most of them are not heralded. This requires that gate output must be measured to know if the operation was successful or not, and is therefore not suited for use in quantum circuits – and only heralded gates can be used to achieve scalable optical quantum computation that employs linear optical components. Another difference is that the new quantum circuit combines effective nonlinearities induced via quantum interference of photons at a beam splitter, as first suggested by KLM. Other heralded gates demonstrated use different entanglement resources, such as entangled photon pairs or quantum teleportation.“The effective optical nonlinearities embedded in the KLM-CNOT circuit rely on the quantum interference between indistinguishable single photons at a beam splitter using parametric down conversion (SPDC) sources,” Takeuchi explains to PhysOrg.com. “If these photons are distinguishable, photons behave like classical particles – and the genuine quantum feature of the circuit disappears. For the KLM-CNOT circuit, single photon sources with very high indistinguishability are required. Moreover, we have to stabilize at least four nested optical path interferometers and maintain their optical paths for several days.” The team overcame this problem by using a very compact 10cm2 displaced-Sagnac interferometer and several partially polarizing beam splitters – and to improve the design further, adds Takeuchi, the team may implement the optical quantum circuit with optical wave guides. This would reduce circuit size by more than an order of magnitude to less than 1cm2. Copyright 2011 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. Explore further 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

Two studies suggest trouble ahead for paywall journals Update

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. (Phys.org)—Two independent studies looking at two aspects of paywalls versus free access to research papers suggest that trouble may lie ahead for traditional journals that continue to expect payment for access to peer-reviewed research papers. In the first study, a small team of researchers from the U.S. and Germany looked at the number of freely available papers on the internet using a web extension called Unpaywall—users enter information and the extension lists sources online for free. In the second study, a team with members from Canada, the U.S. and Germany looked at the popularity of a website known as Sci-Hub that collects and freely distributes research papers. Both groups have written papers describing their studies and results and have uploaded them to the PeerJ Preprints server. Free access to research papers is a hot topic in the research community, perhaps indicating coming changes to the status quo. The traditional model, in which a researcher pays for the privilege of reading published articles on journal sites like Science and Nature in order to cite work by others, is under fire. Many have claimed the system is unfair to those who cannot afford to pay such fees. Meanwhile, journal sites maintain their stance that the only way they can continue to exist as profitable entities is to charge access fees. They note also that they provide a valuable service—peer review. In these two new efforts, the researchers with both teams hint that the argument may soon become moot, as people who want to read research papers for free find easier access.In the first paper, the researchers worked with the team that makes the Unpaywall extension to get statistics on its use. They report finding that nearly half (45 percent) of all of the papers that people searched for using the app in 2015 were available for free. They also report that overall, users were able to find free versions of 47 percent of articles they were looking for.In the second paper, the researchers worked with the team behind Sci-Hub, which many have described as a pirating site. They report that visitors could access 85 percent of articles that were still behind a paywall. They found also that the percentage was even higher for papers held behind Elsevier paywalls. They note that the team at Sci-Hub told them that efforts to shut down their site through legal means have resulted in free press, increasing its user base—a term they described as the “Streisand Effect”—after Barbra Streisand, who famously tried to stop distribution of aerial photographs of her home several years ago, inadvertently exposing the photographs to many more people. Citation: Two studies suggest trouble ahead for paywall journals (Update) (2017, August 8) retrieved 18 August 2019 from https://phys.org/news/2017-08-paywall-journals.html Paywall browser extension lets users read some paywalled papers for free Credit: Charles Rondeau/public domain © 2017 Phys.org , Science More information: Himmelstein DS, Romero AR, McLaughlin SR, Greshake Tzovaras B, Greene CS. (2017) Sci-Hub provides access to nearly all scholarly literature. PeerJ Preprints 5:e3100v1 doi.org/10.7287/peerj.preprints.3100v1 , peerj.com/preprints/3100v1/Piwowar H, Priem J, Larivière V, Alperin JP, Matthias L, Norlander B, Farley A, West J, Haustein S. (2017) The State of OA: A large-scale analysis of the prevalence and impact of Open Access articles. PeerJ Preprints 5:e3119v1 doi.org/10.7287/peerj.preprints.3119v1 , peerj.com/preprints/3119/ Journal information: Nature Explore furtherlast_img read more

Bad hair days connected to confidence

first_imgAs if one bad hair day wasn’t enough to ruin a woman’s day, a new study reveals that women spend 20 years of their lives suffering from a bad hair day, and that can affect their mood and confidence.Findings showed that eight out of 10 women believe their glory, self-worth and beauty lies in their hair, reports femalefirst.co.uk.On an average, women wake up with unruly hair at least three times every week. This means that the average British female will have 7,332 bad hair days in a lifetime — equivalent to 20 years of her life suffering from bad hair.This results in mood swings and leads to their feeling depressed for at least four hours and 26 minutes during the day, and also reduces their confidence.‘Women feel like entirely different individuals when their hair does not behave. This makes them tired, grumpy and less confident. In contrast, a great hair day makes them feel sexy, confident and ready to take on the world,’ says the study.last_img read more

NSHM to introduce 19 specialised new UG PG courses

first_imgKolkata: NSHM Knowledge Campus, one of the most sought after educational institutes, will introduce 19 specialised new undergraduate and postgraduate courses starting this Academic Session, 2018-19. With the whole world undergoing a complete paradigm shift in the education sector, NSHM is offering a gamut of specialised courses, as newly affiliated by the University. The courses are BBA in Sports Management and Global Business, BSc in Gaming & Mobile Application, Interior Designing, Behavioural Science & Applied Psychology, Culinary Science and Medical Lab Technology, MSc in Data Science, Also Read – Heavy rain hits traffic, flightsHuman Computing & AI, Information & Cyber Security, Clinical Psychology and Hospitality Management and Masters in Travel & Tourism Management, Optometry and Public Health, MSc in Dietetics, Fashion, Digital Films and Visual Communication.For the first time, NSHM is also going to be double shift college — day and evening from the ensuing academic year. Addressing a press conference on Tuesday, Prof Saikat Maitra, Vice-Chancellor, Maulana Abul Kalam Azad University of Technology said: “NSHM Knowledge Campus has championed the cause of the new era by introducing the much-needed forward looking courses. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe group has thoroughly researched and understood the need of the hour. Education should be able to produce quality human resource that would seamlessly integrate into the industry and work profitably. The new courses aim to make students industry-ready and will be different from the traditional courses.”NSHM Chief Mentor and Trustee, Cecil Antony said NSHM is investing over Rs 35 crore to build the state of the art infrastructure for the new courses. With state-of-art campuses in Kolkata and Durgapur, the premier education hub offers 26 under graduate and 21 post graduate courses in various disciplines.last_img read more

Arvind roars common man soars

first_imgThe AAP won 67 of the 70 seats at stake and grabbed 53% of the vote share. The unprecedented drubbing of the Bharatiya Janata Party (BJP) can be summarized as the rejection of the politics practiced by the Narendra Modi government after being given a resounding majority in the Lok Sabha polls. In May the people empowered a “chaiwala’s son” and in February they rejected the Prime Minister who wore a suit worth Rs 10 lakh and whose colleagues had the gumption to say promising Rs 15 lakh to every poor was just a “chunavi jumla” (poll gimmick). No wonder, the difference between BJP and the AAP in the vote share of urban poor is a staggering 41%. Also Read – Need to understand why law graduate’s natural choice is not legal profession: CJI  The arrival of Arvind Kejriwal and the Aam Aadmi Party marks beginning of new politics. Delhi in the past three decades has undergone a profound demographic change. The migrants arriving in the city, which is North India’s El Dorado, have given a new character to its social and cultural life. From being poor tenants in the unauthorized colonies they are now proud holders of plots but have been fighting with the successive governments for assertion of their civic rights. Also Read – Health remains key challenge in India’s development: KovindTheir struggle has not been limited to the recognition of their housing plots. They eke out a living fighting various forces of corruption aka government. The Congress and the BJP all these years instead of holding their hand have depended on poll malpractices, exploiting their poverty to get their mandate. When Kejriwal during the campaign said that do accept liquor and money from the Congress and the BJP but vote for me, he showed that he had his ear to the ground. BJP in its defence has said that its vote share has remained same as in the last assembly elections held in December 2013. What its leaders did not mention is that their vote share has come down by over 13 percent from the last Lok Sabha polls. How a party could have such a short honeymoon with voters has left political observers flummoxed. The only other such instance was in 1985, when having sent majority of the MPs from the state on Congress ticket, Ramakrishna Hegde’s Janata Party government in Karnataka staged a comeback in assembly polls three months later.The BJP vote share has dipped drastically because Narendra Modi has had little to showcase from his much-flaunted agenda of vikas (development). On the contrary, it has allowed the agenda of Hinduvta to overtake the charter of development. The BJP leadership in these months had been busy using the mandate to smother any competition that it faced within and outside the party. Such politics has been rejected by the people.People of Delhi have given a huge mandate to Kejriwal and their expectations will be commensurate to that.  Kejriwal has five years to come good on his promises. The Indian voter is notoriously fickle after all.last_img read more

Three city students arrested over involvement in drug peddling racket

first_imgKolkata: In a major breakthrough, three students of well known private colleges in the city were arrested on charges of being involved in a drug peddling racket.Substantial quantities of MDMA and LSD were recovered from them. 22-year-old Soumik Mukherjee is a BBA student, while 29-year-old Mriganka Banerjee is a Computer Science student. The third arrested youth, 24-year-old Koustav Kar, is an MCA student.Acting on a tip off, officers of the Narcotic Cell of Kolkata Police conducted a raid in the house of Soumik at Ushapally in South Kolkata. Police recovered 2 gms of MDMA and 34 blots of LSD from him. Also Read – Heavy rain hits traffic, flightsPolice questioned him to know from whom he had managed to get the chemical drugs. During interrogation, the sleuths came to know about Mriganka, who is a resident of Vivek Nagar. He is a student of the same college as that of the arrested BBA student.Police also came to know that the father of the arrested computer science student is a retired custom officer. Police recovered 14 gms of MDMA and 3 MDMA pills from the youth. They also learnt that he used to buy the same through dark web. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedLater, police picked up a MCA student of another private college. He was also arrested from Ushapally. He resides close to the house of the arrested BBA student. Police seized 1 gm of MDMA from him.According to a police officer, it seems that all the three youths were well known to each other and they kept in regular touch among themselves. One of the three youths used to buy the drugs and the task of the other two was to distribute the same, police suspect. They are trying to ascertain whether any more persons are involved in the racket.It may be mentioned that officers of Kolkata Police had been maintaining vigil at different places, including pubs and night clubs. On Wednesday, police received the information about the students and their involvement in the drug peddling racket.It may be recalled that in April, Narcotics Control Bureau (NCB) had arrested four persons, including a 19-year-old girl, who was a student of class X from an open school.They were arrested from South Kolkata as well. LSD blots and ganja was recovered from them. Two more persons were also arrested in December 2017, where one of the arrested persons had obtained a management degree from a private management college in Salt Lake, while the other one was a student of event management.last_img read more

Psychotherapy for gut disease has longterm benefits

first_imgWhile doctors have known for some time that psychological therapy can reduce the symptoms of irritable bowel syndrome — a gastrointestinal disorder — in the short term, a new study has found that the benefits can extend up to one year after the completion of the therapy.The beneficial effects of psychological therapy for irritable bowel syndrome (IBS) appear to last at least six to 12 months after the therapy has concluded, the study said. “Our study is the first one that has looked at long-term effects,” said senior author Lynn Walker, professor of pediatrics at Vanderbilt University Medical Center in Tennessee, US.  Also Read – ‘Playing Jojo was emotionally exhausting’The study analysed the results of 41 clinical trials involving more than 2,200 patients from a number of different countries. “We found that the moderate benefit that psychological therapies confer in the short term continue over the long term. This is significant because IBS is a chronic, intermittent condition for which there is no good medical treatment,” Walker noted.Characterised by chronic abdominal pain, discomfort, bloating, diarrhoea or constipation, IBS is classified as a disorder of the “brain-gut axis.” Although no cure is known, there are treatments to relieve symptoms including dietary adjustments, medication and psychological interventions.The study was published in the journal Clinical Gastroenterology and Hepatology.last_img read more

Mamata condoles Ananth Kumars death

first_imgKolkata: West Bengal Chief Minister Mamata Banerjee Monday expressed her deep grief over the passing away of Union minister Ananth Kumar. “Saddened at the passing away of Ananth Kumar ji, six time MP and Union Cabinet minister. My heartfelt condolences to his family, friends and supporters,” Banerjee wrote in her Twitter handle this morning. Union Parliamentary Affairs Minister Ananth Kumar died at a private hospital in Bengaluru in the early hours of Monday after battling lung cancer for several months, hospital authorities said. Kumar, 59, had come back to Bengaluru only recently after undergoing treatment in the US and Britain.last_img

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