(PhysOrg.com) — Jeff Bezos the founder of Amazon.com has embarked on an interesting and unique project that, if all goes well, will last the test of time, a whole lot of time. He is looking to create a clock that is able to run for 10,000 years. $42 million has already been put towards the creation of the clock to date, all of it from Mr. Bezos private fortune. Explore further To Mr. Bezos the clock is not just about creating a timepieces that will give him the ultimate in bragging rights, even among the super rich. It is his hope that by building a clock meant to stand the ages it will alter the way that humans think about time and the way that we act, encouraging future generations to take a longer-term view. More information: www.10000yearclock.net/learnmore.html and longnow.org/clock/ If, at first, this sounds like a bit of a strange project you have to understand why Mr. Bezos wants to make a giant clock that will keep time long after his great-great-grandchildren are dead and gone and Amazon.com is less than a faint memory in the collective of the web. Citation: Amazon.com founder to make 10,000 year clock (2011, June 23) retrieved 18 August 2019 from https://phys.org/news/2011-06-amazoncom-founder-year-clock.html © 2010 PhysOrg.com Clocking in and out of gene expression The clock, which will be built into a mountain ridge, represents a monumental feat of engineering, since it will have to run for as long as it took to create all of human civilization. Keeping a clock operational and accurate over this epic of a time span is no small feat. The clocks accuracy will be maintained by a complex set of calculations made by the Jet Propulsion Laboratories that will calculate the suns position at noon for the next 10 millennium. This will allow the clock to automatically correct its time. 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.
More information: Yves-Alexandre de Montjoye, César A. Hidalgo, Michel Verleysen, and Vincent D. Blondel. “Unique in the Crowd: The privacy bounds of human mobility.” Scientific Reports. DOI: 10.1038/srep01376 As the focal point of their paper, the researchers used these results to develop a mathematical formula that tells the probability of uniquely identifying an individual based on the data’s temporal and spatial resolution. Essentially, they found a formula for estimating privacy. Don’t stop anonymizing data 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. Copyright 2013 Phys.org All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of Phys.org. These results highlight the potential risk to individual privacy and anonymity from mobility data combined with publicly available information. The researchers hope that the findings will help inform the design of future policies and technologies.”Our results help us understand what is possible and what is not possible,” de Montjoye told Phys.org. “We all have a lot to gain from this data being used. Our formula allows us to estimate privacy, so now the question is how do we use it to balance things out and make it a fair deal for everybody?”In the future, de Montjoye plans to continue to investigate the consequences of what large amounts of personal data mean for an individual’s privacy. “Another area we want to pursue is to apply this same methodology to other sources of human-generated data,” he said. Journal information: Scientific Reports (Phys.org) —While most people know that using a cell phone means that the phone’s location is being recorded, a new study has revealed just how little information is required to determine an individual’s personal identity. By analyzing 15 months of cell phone mobility data from 1.5 million people, researchers have found that only four spatio-temporal points (an individual’s approximate whereabouts at the approximate time when they’re using their cell phone) are all that’s needed to uniquely identify 95% of the individuals. The study has implications for modifying privacy law in order to keep pace with technological advances. An artistic representation of being “unique in the crowd,” representing the new finding that human mobility traces are highly unique, and mobility data can be used to reconstruct individuals’ movements in space and time. The original photo is on the right. Credit: Yves-Alexandre de Montjoye, et al. Original image “Grand Central Station” by theotter The researchers, Yves-Alexandre de Montjoye at MIT in Cambridge, Massachusetts, and Université Catholique de Louvain in Belgium, and his coauthors, have published their paper in Nature’s Scientific Reports on how cell phone data places fundamental constraints on the privacy of an individual’s mobility traces.The reason that four locations are sufficient to identify most people is simply that human mobility is unique. Just as how everyone has unique fingerprints, everyone has unique daily travels. In the case of fingerprints, Edmond Locard showed in 1930 that only 12 points are needed to uniquely identify a fingerprint. Likewise, the researchers’ data shows that just four spatio-temporal points are needed to uniquely identify the mobility trace of an individual. In other words, it’s not likely that someone else will be in the same locations as you are at four different times of day. In fact, the researchers found that knowing just two randomly chosen points can uniquely identify more than 50% of the individuals.As the researchers noted, these four points that allow for the identification of individuals could come from information that is publicly available, such as the individual’s home address, workplace address, or Twitter posts. One might expect that the data would provide more anonymity by decreasing the resolution of the data, which is done by increasing the time range from one hour to several hours and increasing the spatial range from a few square meters to several hundred square meters. As an analogy, decreasing the resolution of a photograph causes people in the photograph to appear blurry and unidentifiable. But this is not what happens when decreasing the resolution of mobility data. Surprisingly, the researchers found that decreased resolution does not make the data that much more anonymous; a few more pieces of information are all that is needed to identify individuals. Citation: Study shows how easy it is to determine someone’s identity with cell phone data (2013, March 25) retrieved 18 August 2019 from https://phys.org/news/2013-03-easy-identity-cell.html The unique traces of mobile phone users, along with the information that can be inferred from them, highlight the importance of understanding the privacy bounds of human mobility. Credit: Yves-Alexandre de Montjoye, et al.
More information: Astronomy & Astrophysics, www.aanda.org/articles/aa/pdf/ … 15/11/aa27274-15.pdf 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)—Exoplanet hunters have so far found hundreds of alien worlds using the transit method. They observe the visual brightness of the star, which drops when a planet crosses in front of the parent star’s disk. However, only a handful of grazing exoplanets—meaning exoplanets that partially transit the host-star’s disc—have been detected and confirmed. Astronomers from the University of Porto in Portugal blame giant dark polar spots on host stars for the difficulties of finding new grazing planets. Their research appears in the November issue of Astronomy & Astrophysics journal. Journal information: Astronomy & Astrophysics © 2015 Phys.org Explore further Astronomers find ‘cousin’ planets around twin stars Schematic view of a grazing planet occulting a polar spot. Credit: M. Oshagh et al. Citation: Astronomers explain the low number of discovered grazing planets (2015, November 9) retrieved 18 August 2019 from https://phys.org/news/2015-11-astronomers-grazing-planets.html When a planet passes in front of a star, it blocks out a tiny portion of the star’s light, reducing its brightness. If the planet, during its transit, does not fully cover the stellar disk, the planetary transit is said to be grazing. While astronomers have discovered plenty of planets, detecting them as they pass in front of a star, only eight have been detected by partial transit of the star’s disk. For example, one of the grazing exoplanets is WASP-67 b, which was detected in 2011. This planet is known to undergo only partial eclipses and its grazing nature was confirmed by a detailed study. The lack of second and third contact makes WASP-67 b hard to track down and complicates accurate measurements of its physical parameters.Prior to the newest research conducted by astronomers from the University of Porto, there has been no study explaining why only so few grazing planets have been discovered. In the new paper, the researchers explore possible explanations for this phenomenon. They point to dark giant polar spots on the host stars.”Our hypothesis to explain the insufficient number of grazing planets is based on the assumption that many grazing planets transit host stars with a dark giant polar spot. As a consequence, the transit light curves disappear due to the occultation of the grazing planet and the polar spot,” the researchers wrote in the paper.Large, dark spots located near the stellar rotational axis, either at high latitude or covering the pole, are common features on stars. They are usually much cooler than the stellar photosphere. The occultation of these dark stellar spots by a planet can generate anomalous results when using the transit method and may lead to an incorrect estimate of the planetary parameters.”If a grazing planet crosses a large polar spot, then the transit depth decreases significantly, considering that the limb-darkening also causes a decrease in the transit depth when compared to a central transit,” the scientists explain.They assume that this leads to a lower signal-to-noise ratio and may cause the transit signal to be below the detection threshold. The signal could be even completely missed. If so, there should be many more planets yet undetected, including planet candidates that were discovered by NASA’s Kepler spacecraft, known as the Kepler Object of Interest (KOI).”We found that more grazing planets should have been detected than have been detected,” the paper reads.The list of detected KOIs could contain many grazing planet candidates, but they have yet to be confirmed. The researchers conclude that at least some of them should be real, and if confirmed, they will partially fill the observed gap of grazing transiting planets. They encourage exoplanet hunters to perform more careful analyses when using grazing transit method in the future.
Multimaterial 3-D laser microprinting using an integrated microfluidic system Nematic liquid crystals (NLCs) are the simplest form of liquid crystal molecules without orderly positions, and they differentiate from pure liquids at the level of the molecular orientation. NLCs have a range of properties that allow them to serve as microreactors and conduct inherent polymerization reactions for intriguing future applications. Current work in the field is still experimental, for example, nematic flows in microfluidic environments, which highlight the potential cross-talk between topological defects in different fields of velocity and molecular orientation. In this work, the scientists observed the phase interface with NLCs for the first time, experimentally accomplished by generating polar-phase domains that were controlled by combining microfluidic confinement, fluid flow rates and laser pulses in practice. Emeršič et al. used the single-component nematic material pentyl-cyanobiphenyl (5CB) in all experiments performed in linear microfluidic channels with a rectangular cross-section. The scientists fabricated the channels with polydimethylsiloxane (PDMS) relief and indium tin oxide (ITO)-coated glass substrates using standard soft lithography procedures. They then filled the microfluidic channels with 5CB in its heated isotropic phase and allowed it to cool down to the nematic phase, before beginning the flow experiments. The scientists also chemically treated the microchannel walls to engineer a strong homeotropic surface to anchor the 5CB molecules. 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. Expansion and contraction of laser-nucleated dowser domains in a moderate nematic microflow. The lifetime of the domain is proportional to the critical velocity and the initial size. Recorded under crossed polarizers at 30 fps, the view field size is 480 µm × 120 µm. Credit: Science Advances, doi: 10.1126/sciadv.aav4283 Nucleation of orientation phase domains in pressure-driven nematic microflows. (A) Schematic illustration of a channel with homeotropic anchoring on the top and bottom surfaces used in the experiment; IR, infrared; ITO, indium tin oxide. (B) The nematic in a channel looks black between crossed polarizers in the absence of flow and gains visible birefringence due to flow-driven director distortion that traps a domain of the flow-aligned state (also called the dowser state from here on); n denotes the nematic director. Strongly absorbed light of the laser tweezers heats the NLC, creating an isotropic (Iso) island that is quenched into the nematic (N) phase when the laser is switched off. The dense tangle of defects coarsens into a single defect loop that traps a flow-aligned dowser state, identifiable as a green area at low velocity. (C) The laser-induced nucleation of dowser domains can be automated and their shape can be dynamically controlled by tuning the flow parameters. Crossed double arrows indicate the orientation of the polarizers. White empty arrows in the bottom left corners indicate direction and qualitative velocity of the flow throughout the paper. Credit: Science Advances, doi: 10.1126/sciadv.aav4283 , Nature Materials Citation: Sculpting stable structures in pure liquids (2019, February 21) retrieved 18 August 2019 from https://phys.org/news/2019-02-sculpting-stable-pure-liquids.html Systematic reshaping of dowser domains under laser action and oscillatory flows. (A) Moving the laser beam transversely across the bulk dowser pinches off a uniform “train” of the domains. (B) A static beam at a low power of 80 mW generates a small isotropic region that cuts a large dowser domain longitudinally in half. (C) The shape and size of the domain can be maintained over long time and length scales by periodically modulating the driving pressure around the value that induces the desired average flow rate. (D) Under an alternating flow, a dowser domain reverses orientation every time the flow direction is changed. The reorientation creates surface point defects and realigning fronts, visible under the microscope as a rapid color change. The energetically unfavorable “old” orientation shrinks into a narrow 2π soliton and pinches the domain boundary (black arrows). (E) Sufficiently rapid flow reversal creates point defect pairs connected by solitons. With the flow turned off, the characteristic length goes to infinity, and the solitons expand, revealing their signature profile in transmitted light intensity (inset). In a slow residual flow, flow-aligned parts shrink more slowly than parts with unfavorable orientation. Scale bars, 20 μm. Credit: Science Advances, doi: 10.1126/sciadv.aav4283 Scientists have developed active matter in the form of living colonies and bioinspired synthetic counterparts. They printed hydrophobic/hydrophilic domains on to liquid mixtures by relying on surfactant nanoparticles and controlled non-equilibrium systems to demonstrate the motion and transition between different rheological regimes. Liquid crystals (LCs) are an ideal system to study the phenomena of interest, such as spontaneous symmetry breaking, topological defects, orientation ordering and external stimuli based phase transitions. More information: Tadej Emeršič et al. Sculpting stable structures in pure liquids, Science Advances (2019). DOI: 10.1126/sciadv.aav4283Xiaoguang Wang et al. Topological defects in liquid crystals as templates for molecular self-assembly, Nature Materials (2015). DOI: 10.1038/nmat4421Anupam Sengupta et al. Liquid Crystal Microfluidics for Tunable Flow Shaping, Physical Review Letters (2013). DOI: 10.1103/PhysRevLett.110.048303Gareth P. Alexander et al. Publisher’s Note:Colloquium: Disclination loops, point defects, and all that in nematic liquid crystals [Rev. Mod. Phys.RMPHAT0034-686184, 497 (2012)], Reviews of Modern Physics (2012). DOI: 10.1103/RevModPhys.84.1229
Shares of three listed state-owned oil marketing companies (OMC) fell up to 4 per cent at close on Tuesday, after the government raised excise duty on petrol by Rs 2.25 per litre and by Re 1 a litre on diesel.Bharat Petroleum Corporation fell by 4.06 per cent to close at Rs 712.90, while shares of Indian Oil Corporation fell by 2.55 per cent to Rs 351.20 on the Bombay Stock Exchange (BSE). Shares of Hindustan Petroleum Corporation Ltd lost 1.60 per cent to Rs 594. The second excise duty hike in three weeks will help raise additional Rs 4,000 crore in four months to March as the government seeks to take advantage of a slump in world oil prices to shore up its revenues without stoking inflation.
Kolkata: With a high demand of tickets for Friday’s IPL match between Kolkata Knight Riders (KKR) and Sunrisers Hyderabad (SRH), the police have taken necessary steps to check black marketing of tickets.At the same time, major steps have been taken to avoid betting at certain parts of the city and its adjoining areas.It may be mentioned that a few youths were arrested a few days ago, when they were found selling tickets of a match at a premium in Maidan area and the police had seized 20 tickets from them. Also Read – Heavy rain hits traffic, flightsThe police have intensified vigil in different parts of the city and steps have been taken so that the black marketers cannot take advantage of the increase in demand for tickets for Friday’s match.Policemen in plain clothes will be posted at different parts around the stadium. The policemen will be keeping a watch to ensure that no one can sell tickets at a premium to make fast money.Sources said that officers of the Anti-Rowdy Squad (ARS) are also maintaining vigil at different parts of the city to ensure that people involved in betting rackets cannot function. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedAt present, the police also need to maintain vigil to avoid online betting as well. The police had earlier arrested a few who used to run rackets involved in online betting and are taking all necessary steps to ensure that online betting does not take place.According to a police officer from Kolkata Police, different sections of the city police will work together to ensure that the IPL match passes peacefully without any untoward incident.While ARS and other departments of Kolkata Police will maintain vigil to check black marketing and cricket betting, a large contingent of police will get posted to ensure that safety and security of people coming to the stadium to watch the match. Policemen of all ranks will remain posted in and around the stadium so that people do not face trouble while watching the match and while leaving the place as well. People have to walk up to the entry of the stadium through proper channels and there are separate arenas for parking of vehicles as well.Traffic police will also be playing a vital role on Friday, as thousands of people will be approaching the stadium at a time. Traffic sergeants will ensure that no traffic congestion takes place in the city and moreover, there will be movement of many VVIPs in the city.
Kolkata: A number of colleges affiliated to Calcutta University have written to the varsity, urging it to extend the admission dates.There are 1.3 lakh seats in colleges under CU, out of which 40,000 are lying vacant, even though the last date for admission has already elapsed on July 10.According to sources in Calcutta University, seats have been lying vacant in a number of colleges, including Sris Chandra college, North City College, South City College, Dum Dum Motijhil College, Lake Town College and Bidhannagar College to name a few. Also Read – 2 Group D staffers held for ‘assaulting’ minorsInitially, the date for completion of admission was fixed on July 6 and was later extended to July 10 in the wake of allegations of extorting money for college admission.These colleges have written to the university with the appeal to extend the dates further.It may be mentioned that the Higher Secondary examination results were published in the first week of July and the admission process was kicked off on June 21.However, soon after the admission process began, there were allegations of extortion in the name of admission from a number of colleges in the city, including Surendranath College, Jaipuria College, South City College, Dinabandhu Andrews College, etc. Also Read – Naka checking to be stricter to rein in speed demonsSimilar allegations also surfaced from colleges in North 24-Parganas, affiliated under West Bengal State University.Chief Minister Mamata Banerjee instructed the state Education department to admit students online, so that they no longer need to turn up physically for the purpose.The police have also cracked the whip and arrested a number of people including students, for being involved in this unfair practice.”We have found out that the colleges located close to railway stations in the suburbs of the city already have their seats filled up,” a senior official of CU said. He expressed his optimism that if the dates are extended then seat occupancy will normalise.