Month: August 2019

The world is running out of helium Nobel prize winner

The world is running out of helium Nobel prize winner

center_img Explore further Dwindling helium supply prompting concerns (PhysOrg.com) — A renowned expert on helium says we are wasting our supplies of the inert gas helium and will run out within 25 to 30 years, which will have disastrous consequences for hospitals and industry.last_img

Prediction or cause Information theory may hold the key

Prediction or cause Information theory may hold the key

first_img More information: Daniel W. Hahs and Shawn D. Pethel, “Distinguishing Anticipation from Causality: Anticipatory Bias in the Estimation of Information Flow,” Physical Review Letters (2011). Available online: link.aps.org/doi/10.1103/PhysRevLett.107.128701 Citation: Prediction or cause? Information theory may hold the key (2011, September 30) retrieved 18 August 2019 from https://phys.org/news/2011-09-theory-key.html Pethel is a scientist working at the Redstone Arsenal in Alabama. Along with Daniel Hahs, he set out to identify a method of distinguishing anticipation from causality using tools from information theory. “Any process that has to react in real time can improve its performance through anticipation, and in studying such processes it is important to find new ways to quantify causality” Pethel says. The question of anticipation versus causality is one that has real-world application in a number of areas. Pethel points out that this issue has implications in covert operations, as well as in financial areas, especially with regard to the development of bubbles. “Is there a way, from passive measurements, to tell what’s driving what?” Pethel and Hahs try to answer this question in Physical Review Letters: “Distinguishing Anticipation from Causality: Anticipatory Bias in the Estimation of Information Flow.”“If a system is generating information, it’s like a fingerprint that can be used to figure out where the information is coming from and where it is going,” Pethel explains. “A quantity called transfer entropy has been used since 1990 to measure information flow in experimental data from neuroscience, finance and even music.”“What we were interested in,” he continues, “is the anticipation issue. We wanted to look at that using transfer entropy, and see if we could discover what’s predicting and what’s causing.”In order to set up the situation, Pethel and Hahs used chaotic systems, which produce information. They were careful that their model would be connected in only one direction. “We set it up so that we know the causality – that x is causing y, but y cannot cause anything for x. However, we designed the y system to be able to predict x to some degree. We then collected data and used transfer entropy to tell us which was the causal system.”When analyzing the results, Pethel and Hahs found something rather interesting: Even though the response system, y, wasn’t the cause, it looked very much like it was under many different test conditions. “There is an anticipatory bias. It’s a very strong effect, the more anticipation there is, the stronger it will be. There is a huge bias going on in some cases, and it is giving the exact wrong answer. The system that was only predictive was indistinguishable from the cause.”The good news is that Pethel and Hahs also noticed that there are some signs that indicate that the presence of a bias. “Even if you can’t pinpoint what the causal source is, you can see some behaviors that provide clues that you need to be on the alert for anticipatory dynamics.”Pethel wants to take this further, though. “We’ve studied the one way system, and now that we know there is a bias, we can account for that, and study systems that have mutual back and forth coupling.”Hopefully, the work will provide helpful clues in understanding how causality can be indentified using information theory. “There’s a level of broad interest,” Pethel says, “since you can deduce causal mechanisms from data. Particularly interesting are financial markets and biological systems where anticipation plays a large role in allowing systems to adapt to a changing environment.” Don’t have all the information? In the quantum world, that doesn’t matter 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.center_img (PhysOrg.com) — “A perplexing philosophical issue in science is the question of anticipation, or prediction, versus causality,” Shawn Pethel tells PhysOrg.com. “Can you tell the difference between something predicting an event and something actually causing an event?” 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. Explore furtherlast_img read more

New stellar stream discovered by astronomers

New stellar stream discovered by astronomers

first_img Citation: New stellar stream discovered by astronomers (2017, December 5) retrieved 18 August 2019 from https://phys.org/news/2017-12-stellar-stream-astronomers.html (Phys.org)—An international team of astronomers has detected a new thin stellar stream in the halo of the Milky Way galaxy. The newly discovered feature, named “jet stream,” could help researchers answer fundamental questions about the mass distribution of the Milky Way’s dark matter halo. The finding was presented November 24 in a paper published on the arXiv pre-print server. © 2017 Phys.org Stellar streams are remnants of dwarf galaxies or globular clusters that once orbited a galaxy but have been disrupted and stretched out along their orbits by tidal forces of their hosts. So far, nearly 20 stellar streams have been identified in the Milky Way, just a few in the Andromeda galaxy, and about 10 outside the Local Group.Astronomers are interested in finding new stellar streams in the Milky Way, as they hope that such features could answer some crucial questions about the the galaxy. For instance, stellar streams could help us understand the large-scale mass distribution of the galactic dark matter halo. Moreover, they could confirm whether or not our galaxy contains low-mass dark matter subhalos.Now, a group of researchers led by Prashin Jethwa of the European Southern Observatory (ESO) has found a new stellar stream in the Milky Way using the Search for the Leading Arm of Magellanic Satellites (SLAMS) optical survey. SLAMS utilizes the 4-m Blanco telescope at Cerro Tololo InterAmerican Observatory in Chile and is used to look for satellites of the Magellanic Clouds. However, the observations conducted by Jethwa’s team in December 2016 and January 2017, have accidentally revealed the presence of a new stellar stream in the Milky Way’s halo.”We recently carried out a mini survey which led to the fortuitous discovery of a thin stellar stream in the outer halo, which we name the jet stream,” the researchers wrote in the paper.According to the study, the jet stream is located about 95,000 light years away from the Earth and crosses the constellations of Hydra and Pyxis. The researchers estimate that the stream has a width of approximately 293 light years, which morphologically places it in the category of thin stellar streams along with Pal 5, GD-1 and ATLAS. The authors suggest that such thinness could indicate that a globular cluster was a progenitor of this stream.The research also revealed that the jet stream has a mass of about 25,000 solar masses, which makes it one of the least massive stellar streams known to date. Moreover, they found that the jet stream consists of mainly metal-poor stars, and its age was calculated to be about 12.5 billion years.Although fundamental parameters of the jet stream were determined by Jethwa’s team, still more studies are necessary to further characterize it and confirm its origin.”Additional imaging is planned to attempt to trace the stream beyond the current survey footprint, followed by a spectroscopic campaign to determine radial velocities, metallicities, and detailed abundances, shedding light on the nature and orbital history of the progenitor. Finally, deeper, uniform imaging along the stream track will be required to robustly detect density perturbations caused by possible subhalo encounters,” the astronomers concluded. Uncovering the origins of galaxies’ halos 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: Discovery of a thin stellar stream in the SLAMS survey, arXiv:1711.09103 [astro-ph.GA] arxiv.org/abs/1711.09103AbstractWe report the discovery of a thin stellar stream – which we name the Jet stream – crossing the constellations of Hydra and Pyxis. The discovery was made in data from the SLAMS survey, which comprises deep g and r imaging for a 650 square degree region above the Galactic disc performed by the CTIO Blanco + DECam. SLAMS photometric catalogues will be made publicly available. The stream is approximately 0.18 degrees wide and 10 degrees long, though it is truncated by the survey footprint. Its colour-magnitude diagram is consistent with an old, metal-poor stellar population at a heliocentric distance of approximately 29 kpc. We corroborate this measurement by identifying a spatially coincident overdensity of likely blue horizontal branch stars at the same distance. There is no obvious candidate for a surviving stream progenitor. False-colour map of the density of stars with 0.1 < g−r < 0.45 from the SLAMS survey. Density in different magnitude ranges is shown using different colour channels: red 20.5 < r < 23.0, green 17.5 < r < 20.5 and blue 15.0 < r < 17.5. The newly discovered stream is labelled. The dotted line shows the future orbit of the LMC, calculated using Kallivayalil et al. (2013) proper motions, which is roughly aligned with the orientation of the Jet stream. The green/blue colour gradient along the southern edge is due to the varying distance distribution of MW disk stars. Credit: Jethwa et al., 2017. Explore furtherlast_img read more

Missing presiding officer found murdered in Raiganj

Missing presiding officer found murdered in Raiganj

first_imgBalurghat: A presiding officer who had gone missing since May 14, was found murdered on Tuesday evening.The corpse of the presiding officer, Rajkumar Roy, was discovered by the local people beside a railway track from Sonadangi area under Raiganj police station in North Dinajpur district.The State Election Commission has sought a report from the District Magistrate of North Dinajpur. The District Magistrate has order a probe by the Criminal Investigation Department (CID). Also Read – Heavy rain hits traffic, flightsRoy, who had been working as an assistant teacher of English in Rahatpur High Madrasha of Karandighi, was deployed as presiding officer at booth no. 48 in Itahar block. On Monday at around 8 pm, he left for toilet from the booth but never returned. His mobile phone was switched off.Worried family members contacted the officials of Itahar block to know his whereabouts. A missing complaint was also lodged at the police station by the concerned BDO.On Tuesday, some local people found a body with multiple stab injuries beside a railway track and informed police. Police went to the spot and suspected the body to be Roy. His family members were also intimated. Later, the deceased’s brother identified him. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedPolice investigation has been initiated in this regard. Preliminary investigation has revealed that Roy was stabbed brutally to death by his assailants. Police said the body was lying in pool of blood. They have sent the body for post-mortem.On Wednesday, the polling personnel staged a demonstration at Ghorimore in Raiganj, demanding arrest of the culprits involved with the crime. The irate polling personnel demanded safety measures from the administration. Sub-divisional district magistrate of Raiganj T N Sherpa, who rushed to the spot to pacify the agitators, was gheraoed and allegedly thrashed by them. Later, a large contingent of police and RAF from Raiganj police station rescued Sherpa and lifted the demonstration.Police superintendent Shyam Singh said the assailants will be arrested soon.last_img read more

Cops paste stickers on vehicles with message warning against use of mobile

Cops paste stickers on vehicles with message warning against use of mobile

first_imgKolkata: The state Transport department and police have jointly initiated a statewide drive to ensure that drivers do not use mobile phones while driving.The police are now pasting stickers and posters containing messages on the quantum of punishment, if one is caught speaking over mobile phone while driving. These are being put up on vehicles so that it creates awareness among drivers. Small stickers are being pasted at a corner of the windscreens of commercial vehicles, so that they keep reminding the drivers of the punishment they have to face if they speak over mobile phone while driving. Also Read – Heavy rain hits traffic, flightsThe message on the posters and stickers is in Hindi and Bengali and it reads: “It is an offence to speak over phone while driving. Fine will be slapped on driver or he will be put behind bars. Driving licence would also get cancelled”.Staring from auto-rickshaws to trucks, posters and stickers are being put up on all vehicles and according to the police, it will immensely help in further bringing down the rate of accidents.The initiative is a part of the Safe Drive Save Life campaign that was initiated by Chief Minister Mamata Banerjee and the state has witnessed a reduction in the number of road accidents due to the initiative. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe state Transport department and the police had initiated taking necessary measures to check driving of vehicles while speaking over mobile phone, after an accident in Murshidabad in which a bus fell from a bridge into the river and claimed several lives. The police have also provided WhatsApp numbers on which common people can send photographs if they find anyone speaking over phone while driving.It may be mentioned that using mobile phone while driving a motor vehicle constitutes “nuisance or danger to the public under Rule 21 of the Central Motor Vehicles Rules, 1989, and the provisions of clause (f) of sub-section (1) of section 19 of the Motor Vehicles act, 1988, empowering a licensing authority to disqualify such an offender from holding a driving licence or revoking such a licence.”The police take immediate action if they even find someone riding a motorcycle with a cell phone tucked into the helmet, with the rider speaking over it while riding the two-wheeler.Now, with the steps taken to create awareness and at the same time legal steps that the police are taking against drivers caught using cell phone while driving, will help in further reduction in the rate of road accidents in the state.last_img read more

Teachers tend to favour middleclass students

Teachers tend to favour middleclass students

first_imgTeachers favour middle-class students in various ways, perhaps unconsciously, a study says.Are teachers simply biased against less privileged students? Or do structural factors also contribute to their unequal responses?Jessica Calarco, Assistant Professor of Sociology at Indiana University in the US, examined these possibilities by using data from a longitudinal, ethnographic study of teachers, students and parents in a socio-economically diverse, public elementary school. Also Read – Add new books to your shelf“Overall, I found that teachers often inadvertently translated students’ class-based behaviour into unequal opportunities in school,” she said.“More specifically, I found that teachers privileged middle-class students by setting middle-class expectations, such as by expecting students to voice their needs and pro-actively seek help,” Calarco said. The teachers tend to grant requests of middle-class students even when they did not want to approve it, the study said. Calarco said those inequalities may have resulted, in parts, from teachers’ subconscious biases.  Also Read – Over 2 hours screen time daily will make your kids impulsiveMore often, however, it seemed that teachers’ unequal responses to students resulted from forces outside their control, including time constraints and pressure from parents.She also discussed the implications of these findings for research on non-cognitive skills, teacher bias and cultural capital as well as for efforts to alleviate inequalities in school.The findings were presented at the 111th annual meeting of the American Sociological Association in Seattle.last_img read more

How your kitchen towels can cause food poisoning

How your kitchen towels can cause food poisoning

first_imgThe humble kitchen towels used for multi-purpose tasks can put your households at potential risk of bacteria that cause food poisoning, say researchers.The findings showed that the towels used for wiping utensils, drying hands, holding hot utensils, wiping/cleaning surfaces, had a higher bacterial count. Coliforms (Escherichia coli) was found to be higher in humid towels, multipurpose towels and in towels from families having non-vegetarian diets. Also Read – Add new books to your shelfThe presence of these potential pathogens from the kitchen towels indicates that they could be responsible for cross-contamination in the kitchen and could lead to food poisoning, the researchers said. “Our study demonstrates that the family composition and hygienic practices in the kitchen affected the microbial load of kitchen towels,” said lead author Susheela D. Biranjia – Hurdoyal, senior lecturer, at the University of Mauritius.”We also found that diet, type of use and moist kitchen towels could be very important in promoting the growth of potential pathogens responsible for food poisoning,” she added. Also Read – Over 2 hours screen time daily will make your kids impulsiveFurther, S. aureus was isolated at a higher rate from families of lower socio-economic status and those with children. Coliform and S. aureus were detected at significantly higher prevalence from families with non-vegetarian diets. Escherichia coli is a normal flora of human intestine and it is released in large numbers in human feces. The presence of Escherichia coli indicates possible fecal contamination and lack of hygiene practices.”The data indicated that unhygienic practices while handling non-vegetarian food could be common in the kitchen,” Biranjia – Hurdoyal said. For the study, presented at the annual meeting of the American Society for Microbiology in Georgia, the team collected total of 100 kitchen towels after one month of use. Out of these 49 per cent had bacterial growth which increased in number with extended family, presence on children and increasing family size. Out of these 49 samples positive for bacterial growth, 36.7 per cent grew coliforms, 36.7 per cent Enterococcus spp and 14.3 per cent S. aureus.”Humid towels and multipurpose usage of kitchen towels should be discouraged. Bigger families with children and elderly members should be especially vigilant to hygiene in the kitchen,” Biranjia – Hurdoyal suggested.last_img read more

Adequate arrangements in place for secure polls Dubey

Adequate arrangements in place for secure polls Dubey

first_imgJALPAIGURI: Vivek Dubey, the Special Police Observer for Bengal, said while talking to media persons in Jalpaiguri on Wednesday that adequate arrangements have been made for the second phase of polls. “I had been told that adequate arrangements had been made in Cooch Behar. Taking lessons from that, we have made foolproof arrangements for the second phase,” said Dubey. 80 percent of the booths will be manned by CAPF personnel, while the remaining 20 percent will be manned by state armed forces. However, even these booths will have web casting and mobile force patrolling for added security. The Observer said that representatives of political outfits had met him. “I have assured them that elections will be free and fair,” he stated. 61 companies of CAPF will be deputed in Jalpaiguri, whereas in the Darjeeling district, 69 companies will be deployed. 9 companies will be deployed in Kalimpong, with 64 companies in Uttar Dinajpur.last_img read more

CM to inaugurate new bust of Vidyasagar today

CM to inaugurate new bust of Vidyasagar today

first_imgKolkata: Chief Minister Mamata Banerjee will inaugurate a new bust of Pandit Ishwar Chandra Vidyasagar on Tuesday, nearly a month after the vandalisation of the bust at Vidyasagar College by suspected BJP supporters.Two programmes related to the reinstallation of the bust will be held on Tuesday. Banerjee will pay floral tribute to the bust of Vidyasagar at a ceremonial programme at Hare School Ground in College Street. She will then walk from there to Vidyasagar College on Bidhan Sarani to attend another programme for reinstallation of the bust, which will be transported to Vidyasagar College from Hare School. Also Read – Rs 13,000 crore investment to provide 2 lakh jobs: MamataWriters, artistes and other eminent persons have been invited to attend the programme by the state department of Higher Education. It was May 14 when BJP supporters participating in an election campaign rally of their national party president Amit Shah allegedly vandalised the bust. The new bust is made of bronze. The one that had been vandalised was made of plaster of Paris. Banerjee will also inaugurate a bronze statue of Vidyasagar that will be installed on the footpath in front of Vidyasagar College facing Bidhan Sarani. Also Read – Lightning kills 8, injures 16 in stateCalcutta University has already deferred the practical examinations of a semester paper of biochemistry that were scheduled to be held at Vidyasagar College on June 11 and 12. The examinations will now be held on June 13 and 14. The biochemistry laboratory of the college is located at the old building on Bidhan Sarani. “The examinations have been deferred to ensure that there is no inconvenience to the examinees,” a senior college official said. An official in the Higher Education department reasoned that the programme is being held at the Hare School ground so that traffic on Bidhan Sarani does not get choked by any means.last_img read more