Ecologists warn of overreliance on unvetted computer source code by researchers

first_img(Phys.org) —A team of scientists, led by ecologist Lucas Joppa of Microsoft Research, has published a commentary piece in the journal Science, highlighting what they say is a growing problem in research efforts. They suggest that an overreliance on source code that has not been properly vetted is increasingly leading to incorrect research effort results. 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 further The problem, Joppa et al, say, is that increasingly, researchers are relying on existing software to perform their research, despite the fact that no one has peer reviewed the software itself. It’s a problem, they say, that is particularly troubling when big applications are used because small coding errors can be compounded. A rounding error in a spreadsheet generally won’t cause much problem, they note, but when a rounding error is repeated over and over again, perhaps millions of times, it can lead to completely inaccurate results.In a Podcast interview with Science, Joppa explains the problems with software use in research have come about mainly due to the software being written by researchers themselves, rather than by trained software engineers. Software written by one research group can very easily become the standard for use by many other groups, despite the fact that it has never been thoroughly tested to ensure it’s giving accurate results.He said another problem is that sometimes, there is a mismatch between equations that have been worked out by researchers and the way they are implemented in software. It can become truly problematic, he points out, when a catch-22 situation arises—when researchers use a software system to find answers to questions they have no other way to find, or verify. If it’s the only way to get the answer, how do they know it’s correct?Resarchers for the current study pulled data from a survey conducted among fellow ecologists. It’s a field, they note, that relies very heavily on big number-crunching applications. Among other findings, the team reports that just 8 percent of 400 scientists who responded reported validating results (from a black-box computer system) with more than one system.The researchers don’t just point out problems with the way software is used in current research efforts; they offer ways to improve the situation as well. The first are the most obvious—make source code open-source and require it to be peer reviewed before journals will accept research articles based on their use. They also suggest journals could help by publishing more articles educating researchers about the problem and how to deal with it. Encouraging colleges and universities to educate students on the issue (and perhaps require more computer science courses) would be helpful too, they add. © 2013 Phys.org Journal information: Science Citation: Ecologists warn of overreliance on unvetted computer source code by researchers (2013, May 17) retrieved 18 August 2019 from https://phys.org/news/2013-05-ecologists-overreliance-unvetted-source-code.html Xerox to offer ‘Ignite’ software upgrade for copiers to let them grade school papers More information: www.sciencemag.org/content/340/6134/814last_img read more

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Field study shows tigers in India follow corridors between groups to maintain

first_imgImage: Wikipedia. (Phys.org) —A team of researchers working in India has found that tigers living in separate geographic areas mate with tigers from other groups by traversing natural corridors. In their paper published in Proceedings of the Royal Society B, the team explains how they analyzed tiger DNA samples from different groups to learn more about their mating patterns. 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: Forest corridors maintain historical gene flow in a tiger metapopulation in the highlands of central India, Published 31 July 2013 doi: 10.1098/rspb.2013.1506AbstractUnderstanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura–Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km2 landscape contains 17% of India’s tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration–drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors. Journal information: Proceedings of the Royal Society B © 2013 Phys.orgcenter_img Explore further Tigers are native to India—part of a tract of land that once stretched from the far eastern parts of Russia to Turkey. As the population of the country has increased, sadly, the population of tigers has dwindled. Now, instead of roaming vast forests, tigers inhabit small geographical zones, where groups of the big cats survive only through the efforts of conservationists. Recent reports suggest that tigers now inhabit just seven percent of the land area in the country. Because of their isolation from other groups researchers have worried that the tigers will all die out due to such a small gene pool. In this new effort, the researchers sought to learn whether tigers from the separated groups are breeding with one another, helping to keep the gene pool diverse enough to be sustainable.To find out, the researchers went into the jungle and collected tiger hair and feces samples from four geographic areas where tigers are allowed to roam free. They brought the samples back to the lab and analyzed the DNA found in them. In so doing, they were able to see that the DNA was from 273 individual tigers and that the four areas were actually just two—two pairs were separated by long thin, natural channels which tigers are still able to traverse. Because of that, the researchers feel confident that the gene pool can be maintained, provided the channels the tigers use are left open. Unfortunately, that might not happen, as the channels are privately owned and one of them has already been leased to a mining company.In studying the tiger DNA the researchers were also able to see periods of sharp decline in genetic diversity over time. The first occurred approximately 700 years ago when human invaders arrived and started clearing forests for agriculture. The second was approximately 200 years ago as India became a part of the British Empire and wood from its forests was felled for timber shipped back to Europe Citation: Field study shows tigers in India follow corridors between groups to maintain gene flow (2013, July 31) retrieved 18 August 2019 from https://phys.org/news/2013-07-field-tigers-india-corridors-groups.html Nepal’s Royal Bengal tiger numbers soarlast_img read more

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Its alive Scientists combine liquid crystals and living bacteria

Distortion of the nematic director detected by optical microscopy. (A) Snapshot of swimming bacteria observed under a microscope with slightly de-crossed polarizer (P) and analyzer (A). The bacterium shown in green box swims from right to left. (B) Optical retardance pattern around a swimming bacterium. (C) Time evolution of the director waves created by rotating flagella in the comoving reference frame. (D) Space–time diagram for director waves extracted for the bacterium shown in C. A total of 240 cross-sections was extracted from 2.4 s of video. Dashed green line depicts phase velocity of the flagella wave. Dots mark an immobilized dust particle. (E) Trajectory of a single bacterium around a tactoid. (F) Trace of isotropic tactoids left by a bacterium at temperature about 0.5 °C below the nematic–biphasic transition point. Observations are made under a microscope with slightly de-crossed polarizer (P) and analyzer (A). Scale bar, 5 μm (A and B); 2 μm (C); 10 μm (E); and 20 μm (F). Copyright PNAS, doi:10.1073/pnas.1321926111 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. Journal information: Proceedings of the National Academy of Sciences Liquid crystal that twists and bends Chiral symmetry breaking of the living liquid crystal (LLC) director pattern caused by a rotating bacterium. (A and B). Schematics of the flows generated by the rotating bacterium. (C) Scheme of the director twist along the vertical z axis. Credit: Copyright PNAS, doi:10.1073/pnas.1321926111 Play Formation of a stripe pattern with disclinations in the LLC sample (h = 50 μm) for high concentration of bacteria, c ∼ 1.6 × 109 cells/cm3. During the video recording, the polarizer was removed and placed back two times. The video is recorded at 0.3 frames/s and played back at 30 frames/s. Credit: Copyright PNAS, doi:10.1073/pnas.1321926111 Aronson notes that their work provides several key insights derived from addressing the challenges they encountered:it demonstrates universal features of the collective motion of self-propelled particles (such as bacteria) in anisotropic media (LC) – for example, the emergence of self-organized textures with a characteristic scale controlled by bacterial activitythe possibility of observing nanoscale dynamic objects, like bacterial flagella, in polarized light the possibility of controlling and manipulating bacterial trajectories n the LC environment a design concept for rewritable microfluidic devices based on their demonstration that the bacteria follow nematic-isotropic boundaries (isotropic – that is, uniform in all orientations –domains can be created in liquid crystals by, for example, local heating with lasers and then erased by cooling the liquid crystal)In addition to these insights, the study uncovered a number of interesting and sometimes surprising results. Addressing the nonequilibrium nature of the collective motion of self-propelled organisms or synthetic particles, Aronson says that self-propelled microorganisms or synthetic swimmers inject energy into the medium at the microscopic scale (that is, the scale of individual particles), which drives the system out of equilibrium. Citation: It’s alive! Scientists combine liquid crystals and living bacteria (2014, January 31) retrieved 18 August 2019 from https://phys.org/news/2014-01-alive-scientists-combine-liquid-crystals.html Furthermore, the scientists discovered that bacterial activity results in this emergence of self-organized textures – for example, stripes – from initially uniform LLCs. The textures emerged with a characteristic length x controlled by a balance between bacteria activity and anisotropic viscoelasticity of the liquid crystal. “The characteristic length decreases with increases in bacterial concentration and bacterial swimming speed,” Aronson explains. “Also, x increases with an increase in experimental cell thickness.” The primary reason for the onset of the self-organized textures is a competition of two effects: the LC tends to align the bacteria along local nematic direction – but bacteria generate flow in the LC which deflects LC molecules from their initial orientation. (A nematic liquid crystal phase is characterized by molecules that have no positional order but tend to point in the same direction.) The characteristic length can therefore be estimated by comparing viscous torque exerted by the bacteria on the LC molecules with the restoring elastic torque in the LC.The researchers also demonstrated activity-triggered transitions from a non-flowing uniform state into a flowing one-dimensional periodic texture, and its subsequent evolution into a turbulent array of topological defects. “We observed a gradual increase in the complexity of emerging self-organized textures,” Aronson tells Phys.org. “At the onset – that is, at a very low concentration of bacteria – we observed the emergence of near-periodic arrays of stripes oriented perpendicular to the original nematic direction. Furthermore, with an increase in the concentration of bacteria, we observed the onset of disclinations” – the nucleation and proliferation of defects – “in the stripe arrays.” For even high concentration of bacteria, he notes, the overall texture is chaotic, with disclination pairs appearing and annihilating seemingly in a random fashion – a state known as active turbulence. (Phys.org) —The prospect of integrated living organisms into a non-living substrate has long held a compelling appeal for those investigating active matter – the study of a type of easily-deformable out of equilibrium soft matter that focuses on the properties of assemblages of self-propelled interacting particles, and an important physical model of living systems. Recently, scientists at Kent State University, Argonne National Laboratory and Northwestern University have proposed the living liquid crystal (LLC) – a new class of active matter with motile rod-shaped bacteria placed in a water-based nontoxic lyotropic liquid crystal (LC) environment. The researchers found that the novel material displays a wide range of useful and occasionally surprising properties that lend themselves to a wide array of potential biosensing, biomedical, submicrometer, autonomous microprobe, and structural imaging applications. More information: Living liquid crystals, Proceedings of the National Academy of Sciences published online before print on January 13, 2014, doi:10.1073/pnas.1321926111 Explore further Yet another interesting finding is that of local melting of the liquid crystal caused by the so-called shear flows produced by bacteria. “With the increase in temperature, nematic and isotropic phases begin to co-exist in a manner analogous to water and ice,” Aronson explains. “Rotating bacterial flagella shear LC molecules, thus causing it to melt.”Finally, notes Aronson, similar studies can be done with of more complex living liquid crystals, including smectics, where molecules form layers that can slide over one another, or cholesteric, in which molecules form helix-like order. In such cases, the scientists expect to find new types of emergent textures Beyond their own work, Aronson sees a range of other research areas that stand to benefit from the results of their study. One such area, he says, comprises biosensing and biomedical devices with unique functionalities, including specific responses to chemical agents, toxins, or photons. “This technique can be used to control and manipulate individual bacteria for the purpose of recognition, analysis, and identification. For example,” Aronson illustrates, “one may think of modifying bacteria to have a specific sensitivity to a particular chemical agent, such as a toxin.” Once the agent is introduced into the cell, bacteria begin to move, thereby triggering the onset of periodic stripes. These stripes can be immediately detected – and in the case of light-sensitive bacteria, can be controlled by light.Swimming bacteria can also serve as autonomous microprobes for determining liquid crystal properties. The bacteria create perturbations in the LC over a wide range of scales, from nanometer (flagella) to hundreds of micrometers (emergent textures). “By studying the LC response to bacterial motion,” Aronson concludes, “we can extract valuable information on LC material properties in confined geometries, such as microchannels. We can also study interaction of nearby swimming bacteria, including flagella interaction effects.” PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen Dr. Igor S. Aronson discussed the paper that he, Researcher Shuang Zhou, Dr. Andrey Sokolov, and Dr. Oleg D. Lavrentovich published in Proceedings of the National Academy of Sciences. “When we first combined living swimming bacteria with a liquid crystal, it wasn’t clear that the bacteria could live and swim in the liquid crystal, or if the liquid crystal is consistent with the bacterial environment,” Aronson tells Phys.org. To address this, the scientists developed a protocol for transferring bacteria to the liquid crystal by suspending the water-soluble liquid crystal used in their experiment in the bacterial growth medium.Another challenge the researchers faced was determining that long-range orientational order of the liquid crystal and the swimming activity of bacteria demonstrate a strong coupling that dramatically alters individual and collective bacterial dynamics. “We found that in the liquid crystal environment we can see bacterial flagella, which are only about 20 nm wide,” Aronson says. More specifically, they observed a birefringence-enabled visualization of microflow generated by the flagella. (Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light.) “This is a very surprising discovery,” Aronson acknowledges. “Due to liquid crystal birefringence, we can flagella in polarized light – and remarkably, this is a non-invasive technique.” “This observation is possible due to strong coupling between the long-range orientational order of the liquid crystal and bacterial activity.” Specifically, nanometer-wide bacterial flagella induce distortions in the liquid crystal on the scale of microns due to orientational order in the liquid crystal – and as a result, these flagella-induced distortions are visible in polarized light. Previous observations of flagella were made either by tunneling electron microscopy, which required drying the bacteria, or fluorescent microscopy, which required a significant modification of the bacteria (for example, by labeling their flagella with fluorescent dyes). ” Emergence of a characteristic length scale in LLCs. (A and B) LLC with inactive bacteria is at its equilibrium state with the director and bacteria (highlighted by ellipses) aligned uniformly along the rubbing direction; (C and D) active bacteria produce periodically distorted director. (E) Proliferation of stripe pattern in the sample of thickness h = 20 μm and for low concentration of bacteria, c ∼ 0.9 × 109 cells/cm3. Oxygen permeates from the left-hand side. (F) LLC patterns in thicker sample (h = 50 μm) and for higher concentration of bacteria, c ∼ 1.6 × 109 cells/cm3. White arrow points toward a higher concentration of oxygen. (G) Zoomed area in F showing nucleating disclinations of strength +1/2 (semicircles) and −1/2 (triangles). Bright dashes visualize bacterial orientation. (H) Dependence of characteristic period ξ on c and h; dashed lines depict fit to theoretical prediction ξ = √(Kh/cα0Iu0). (Inset) Illustration of collapse of the data into a universal behavior that follows from the theoretical model. (I) Director realignment (shown as a rod) caused by the bacterium-generated flow (shown by dashed lines with arrows). See also Movies S5 and S6. Scale bar, 50 μm (A–D); 100 μm (E–G). Error bars, ±10% standard error of the mean (SEM), except for ±30% SEM at c/c0 = 5.05. Copyright PNAS, doi:10.1073/pnas.1321926111 Moreover, the scientists found a dynamic phenomena caused by coupling between the activity-triggered flow and long-range orientational order of the medium. In one such case, the scientists observed that the bacteria closely follow the local nematic direction. “This is primarily caused by strong viscosity anisotropy (the property of being directionally dependent, as opposed to isotropy) in the liquid crystal, Aronson comments. In addition, he points out, that moving perpendicular to the local nematic direction is not energetically favorable since it causes strong distortions of the local orientational order. © 2014 Phys.org. All rights reserved. read more

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Photon afterglow could transmit information without transmitting energy

first_img © 2015 Phys.org Spacetime diagram of the scientists’ proposed set-up, where the dotted lines indicate the first and last light rays emanating from Alice. Although no energy is transmitted, the receiver (Bob) must provide the energy needed to detect the incoming signal. Credit: Jonsson, et al. ©2015 American Physical Society More information: Robert H. Jonsson, et al. “Information Transmission Without Energy Exchange.” Physical Review Letters. DOI: 10.1103/PhysRevLett.114.110505 Explore further The physicists, Robert H. Jonsson, Eduardo Martín-Martínez, and Achim Kempf, at the University of Waterloo (Martín-Martínez and Kempf are also with the Perimeter Institute), have published a paper on the concept in a recent issue of Physical Review Letters.Currently, any information transmission protocol also involves energy transmission. This is because these protocols use real photons to transmit information, and all real photons carry energy, so the information and energy are inherently intertwined.Most of the time when we talk about electromagnetic fields and photons, we are talking about real photons. The light that reaches our eyes, for example, consists only of real photons, which carry both information and energy. However, all electromagnetic fields contain not only real photons, but also virtual photons, which can be thought of as “imprints on the quantum vacuum.” The new discovery shows that, in certain circumstances, virtual photons that do not carry energy can be used to transmit information.The physicists showed how to achieve this energy-less information transmission by doing two things:”First, we use quantum antennas, i.e., antennas that are in a quantum superposition of states,” Kempf told Phys.org. “For example, with current quantum optics technology, atoms can be used as such antennas. Secondly, we use the fact that, when real photons are emitted (and propagate at the speed of light), the photons leave a small afterglow of virtual photons that propagate slower than light. This afterglow does not carry energy (in contrast to real photons), but it does carry information about the event that generated the light. Receivers can ‘tap’ into that afterglow, spending energy to recover information about light that passed by a long time ago.”The proposed protocol has another somewhat unusual requirement: it can only take place in spacetimes with dimensions in which virtual photons can travel slower than the speed of light. For instance, the afterglow would not occur in our 3+1 dimensional spacetime if spacetime were completely flat. However, our spacetime does have some curvature, and that makes the afterglow possible.These ideas also have implications for cosmology. In a paper to be published in a future issue of Physical Review Letters, Martín-Martínez and collaborators A. Blasco, L. Garay, and M. Martin-Benito have investigated these implications.”In that work, it is shown that the afterglow of events that happened in the early Universe carries more information than the light that reaches us from those events,” Martín-Martínez said. “This is surprising because, up until now, it has been believed that real quanta, such as real photons of light, are the only carriers of information from the early Universe.”The new protocol could also have practical applications for quantum communication technology.”The afterglow also occurs in flat spacetime of dimensions other than 3+1,” Jonsson said. “It occurs, in particular, in the case where there is only one spatial dimension, such as is effectively the case in an optical fiber. We are currently investigating applications of our results to quantum communication through optical fibers.” Confirming Einstein, scientists find ‘spacetime foam’ not slowing down photons from faraway gamma-ray burst (Update)center_img Journal information: Physical Review Letters (Phys.org)—Physicists have theoretically shown that it is possible to transmit information from one location to another without transmitting energy. Instead of using real photons, which always carry energy, the technique uses a small, newly predicted quantum afterglow of virtual photons that do not need to carry energy. Although no energy is transmitted, the receiver must provide the energy needed to detect the incoming signal—similar to the way that an individual must pay to receive a collect call. Citation: Photon ‘afterglow’ could transmit information without transmitting energy (2015, March 31) retrieved 18 August 2019 from https://phys.org/news/2015-03-photon-afterglow-transmit-transmitting-energy.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

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Study shows visual clues important for pigeons homing abilities

first_img Most everyone knows that homing pigeons are good at finding their way home when released from a distant vantage point, but, despite a lot of study by a lot of scientists, it is still not clear just how exactly the birds do what they do. This new study suggests that at least for known flight patterns, the birds rely mainly on visual cues.In humans, visual information taken in by one eye passes into one of the brain’s hemispheres and is then shared with the other hemisphere via the corpus coliseum—birds do not have such a connection, which suggests that visual information from one eye is not shared between hemispheres. This provides a unique opportunity to test whether homing pigeons rely on visual cues to make their way home—by covering one eye as the bird flies. Credit: © Emma Truswell (Phys.org)—A small team of researchers with Oxford University in the U.K. and the University of Pisa in Italy, has through experimentation, found that homing pigeons use visual cues to help them find their way home. In their paper published in Proceedings of the Royal Society B, the group describes their study and results which they suggest, help explain the birds’ remarkable abilities. Credit: © Emma Truswell © Antone Martinho Citation: Study shows visual clues important for pigeons homing abilities (2015, October 7) retrieved 18 August 2019 from https://phys.org/news/2015-10-visual-clues-important-pigeons-homing.html Journal information: Proceedings of the Royal Society B Credit: © Emma Truswell 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 Explore further Credit: © Antone Martinho Credit: © Emma Truswell To test whether visual clues are an important navigational aid, the researchers enlisted the assistance of 12 homing pigeons, each trained to follow a four kilometer flight path from one site to another. But, each was trained with one eye covered. Once they were trained, the team then had the birds fly the same route 18 times with the other eye covered to see if they followed the same route. As it turns out, the route was not the same, which suggested the bird had to rely on other means (odors, magnetic fields, etc.) to figure out the way home—they seemingly “forgot” how to get home as they had already learned. Birds that served as a control group, on the other hand, flew very nearly the exact same path to get home each time.The team reports that GPS data from sensors on the birds indicated that they appeared to rely more and more on memorized visual clues (rivers, roads, etc.) the more times they flew the same route, which comes close to proving that using visual cues is one of the primary ways that pigeons find their way home. Passenger pigeons help to navigate © 2015 Phys.org More information: Asymmetric visual input and route recapitulation in homing pigeons, Published 7 October 2015.DOI: 10.1098/rspb.2015.1957AbstractPigeons (Columba livia) display reliable homing behaviour, but their homing routes from familiar release points are individually idiosyncratic and tightly recapitulated, suggesting that learning plays a role in route establishment. In light of the fact that routes are learned, and that both ascending and descending visual pathways share visual inputs from each eye asymmetrically to the brain hemispheres, we investigated how information from each eye contributes to route establishment, and how information input is shared between left and right neural systems. Using on-board global positioning system loggers, we tested 12 pigeons’ route fidelity when switching from learning a route with one eye to homing with the other, and back, in an A-B-A design. Two groups of birds, trained first with the left or first with the right eye, formed new idiosyncratic routes after switching eyes, but those that flew first with the left eye formed these routes nearer to their original routes. This confirms that vision plays a major role in homing from familiar sites and exposes a behavioural consequence of neuroanatomical asymmetry whose ontogeny is better understood than its functional significance.last_img read more

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Scanning for skyrmions Scientists directly image skyrmion cluster state transitions in irongermanium

first_img Citation: Scanning for skyrmions: Scientists directly image skyrmion cluster state transitions in iron-germanium nanodisks (2016, May 26) retrieved 18 August 2019 from https://phys.org/news/2016-05-scanning-skyrmions-scientists-image-skyrmion.html While LTEM is a powerful tool for imaging magnetic structures with nanometer-scale resolution, and has been used to image skyrmions by Dr. Xiuzhen Yu1, Tian notes that direct imaging of individual skyrmions in nanodisks with a size on the order of ~ 100 nm is still challenging due to the influence of Fresnel fringes at the sample edge. “By utilizing a top-to-down method with FIB technique, we fabricated nanodisks of various diameters from bulk FeGe enclosed with amorphous PtCx composite in order to enhance the mechanical strength and thereby precise manipulation of the nanodisk. “We’re very lucky that edge coating with conducting PtCx composites was found to greatly weaken the Fresnel fringes near the edge boundary, and that by so doing enables us to extract the magnetic information in nanodisks smaller than 180 nm.”The scientists state that the team’s results have immediate implication for designing future skyrmion-based devices, such as multibit memory cells. “We give the direct proof that single skyrmion can exist in nanostructured elements,” Tian says. “Given the similarity between the skyrmions and magnetic vortices in soft magnetic nanodisks, the observed individual skyrmions will provide a viable alternative to spin-torque vortex-oscillator devices, and be a potential candidates for microwave signal-processing applications.” The paper points out that the theory-predicted target skyrmion in chiral magnets was not observed in the present experiment due to weak magnetic contrast and Fresnel fringes. “Target skyrmions, a concentric helicoidal undulation predicted previously by Dr. Du, may spontaneously exist in small size nanodisks without an external magnetic field, which is more suitable to skyrmion-based devices,” Tian tells Phys.org. “It shows that target skyrmion stability will increase as nanodisk size decreases. However, at sizes below 100 nm, the weak artificial contrast from the edge will diffuse the real magnetic structure though the PtCx coating, and so significantly reduce the edge effect. Therefore, to realize the observation of target skyrmions, other magnetic microscopy techniques such as electron holography should be considered to avoid Fresnel fringe interference.”Moving forward, says Tian, by cooperative research between his nanomagnet physical properties team and Che’s structural characterization team, the researchers will target several important issues in future, including searching for target skyrmions by varying disk size, thickness or other conditions by using electron holography, as previously noted; studying the current-driven motion of skyrmions in confined geometries; performing manipulation and electrical detection of skyrmions; and developing new techniques to fabricate nano-sized samples that are more controllable and more efficient for large-scale production.In closing, Tian tells Phys.org that other areas of might research benefit from their study. “The techniques used in our study, such as our focused ion beam patterned procedure and transport intensity equation analysis, can be applied to other micromagnetics research. Moreover, since skyrmions have many features in common with Abrikosov vortices in superconductors, our results may provide some inspirations in this field.” , Nature Fig. S2. Underfocused Lorentz TEM images of a 330-nm FeGe nanodisk at 220 K under an external magnetic field. At zero field, the ground state consists of four helical periods. With the increase of the external field, some skyrmions were nucleated from the helix at 0.45 kOe, and the skyrmions eventually occupied the whole disk at 0.47 kOe. After the number of skyrmions Ns reaches the maximum of 11, i.e., eight skyrmions circle around the edge of the disk, with three inside the circle. Further increasing the external field, the number of the inner skyrmions, in turn, merges to 2 at 0.81 kOe and 1 at 0.98 kOe. It’s worth noting that, at 0.98 kOe, the eight circumambient skyrmions begin to rotate around the center one, leading to a ring-like structure (see Movie S3). Red circles in the white plate at the corner of each panel point out the position of skyrmions and helixes. All images are extracted from a video captured at a defocus value of −288 μm and an exposure time of 0.2 s. Credit: Xuebing Zhao, et al. (2016) Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks. Proc Natl Acad Sci USA 113 (18) 4918-4923. Fig. 1. Variations of spin texture with magnetic field in a 270-nm FeGe nanodisk at T = 100 K. (A) TEM image of the FeGe nanostripe surrounded by an amorphous PtCx layer. (B) The intact magnetic contrast in ground state under underfocused conditions of Lorentz TEM with a defocus value of −192 μm. The magnetic field is applied perpendicular to the stripe plane. (C–L) Magnetic-field dependence of the spin texture at (C) 0 kOe, (D) 1.42 kOe, (E) 1.62 kOe, (F) 1.96 kOe, (G) 2.76 kOe, (H) 3.04 kOe, (I) 3.40 kOe, (J) 3.70 kOe, (K) 3.91 kOe, and (L) 3.98 kOe. The color wheel in L indicates the direction and strength of inplane magnetization at each point. For clarity, some typical spin textures in C, D, and I are zoomed in M, N, and O, respectively. (P) A single skyrmion. The white arrows represent the in-plane magnetization at each point. (Q) The phase diagram in H space. Ns, skyrmion numbers. Credit: Xuebing Zhao, et al. (2016) Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks. Proc Natl Acad Sci USA 113 (18) 4918-4923. Observation of skyrmions in a ferromagnet with centrosymmetry Prof. Mingliang Tian (Chinese Academy of Science) and Prof. Renchao Che (Fudan University) discussed the paper that they and their colleagues published in Proceedings of the National Academy of Sciences. One of the main challenges the team encountered, Tian tells Phys.org, was demonstrating the direct visualization of skyrmion cluster states of in nanodisks fabricated from iron-germanium. The scientists accomplished this, he adds, by using high-resolution Lorentz transmission electron microscopy to report the magnetic field-driven dynamics of individual skyrmions in nanodisks with diameters on the order of several skyrmions. “Real-space imaging of skyrmions is essential for addressing the dynamic behaviors of individual skyrmions,” he explains. “However, the real implementation is highly challenging because of limitations in spatial resolution, sensitivity and the edge effect of the nanostructure on the recorded contrast of Lorentz transmission electron microscopy.” Lorentz transmission electron microscopy (LTEM) is used to study a material’s magnetic domains by imaging the deflection of electrons caused by the Lorentz force in magnetic fields. “The latter issue seriously affects the visualization of individual skyrmions in nanostructures with sizes below 200 nm due to the presence of Fresnel fringes, formed at the edge of the nanostructure,” adds Prof. Renchao Che, director of Fudan University’s LTEM lab. “This is because LTEM imaging requires an out-of-focus condition that causes the Fresnel fringes to smear out the recorded magnetic signal in the vacuum/sample interface.”As described in the paper, Tian’s team members and co-authors, Dr. Haifeng Du and doctoral student Chiming Jin, developed a technique to reduce the interfacial Fresnel fringes in the Lorentz TEM images by using a focused ion beam (FIB) to encircle the outer size-tunable nanodisks with a layer of amorphous platinum-carbon alloy (PtCx). “This significantly reduced the size range of the artificial magnetic contrast,” Tian explains, “thus leading to the direct image of the skyrmion cluster states in 100 nm scale disks.” Journal information: Proceedings of the National Academy of Sciences PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen 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 further Play A video captured in Lorentz TEM showing that the eight circumambient skyrmions begin to rotate around the center one, as soon as the two skyrmions in the center merged into one, in a 330-nm FeGe nanodisk at 0.98 kOe, T = 220 K. The defocus value is −288 μm. Credit: Xuebing Zhao, et al. (2016) Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks. Proc Natl Acad Sci USA 113 (18) 4918-4923. More information: Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks, PNAS May 3, 2016, vol. 113 no. 18 4918-4923, doi:10.1073/pnas.1600197113Related1Real-space observation of a two-dimensional skyrmion crystal, Nature 465, 901–904 (17 June 2010), doi:10.1038/nature09124 © 2016 Phys.org. All rights reserved. Another issue the researchers encountered was determining the relationship between temperature, magnetic field, and disk size. “The real challenge in building this relationship comes from nanofabricating small disk samples,” Tian notes. “We address this by using a top-down method to directly and controllably fabricate varied-size nanodisks.” He adds that their results contrast significantly with the current expectations in bulk or two-dimensional films, where the skyrmions form closely-packed lattice arrangements. “We found that, at low temperatures – below ~200 Kelvin for FeGe nanodisks – the skyrmions form cluster states with maximum skyrmion number proportional to the disk diameter. This differs from skyrmion lattices at higher temperatures with the maximum skyrmion numbers proportional to the square of the disk diameter.” Moreover, he adds, the magnetic field transition interval of skyrmion cluster states decreases with ascending temperature. “I was very excited when I directly observed, for the first time, the cascading transition and the fluctuations of skyrmion cluster states driven by the magnetic fields.” Fig. 2. Evolution of spin texture with magnetic field in a 270-nm FeGe nanodisk at temperature T = 220 K. (A–L) Magnetic-field dependence of the spin texture for (A) 0 kOe, (B) 0.44 kOe, (C) 0.47 kOe, (D) 0.51 kOe, (E) 0.52 kOe, (F) 0.56 kOe, (G) 1.01 kOe, (H) 1.11 kOe, (I) 1.37 kOe, (J) 1.41 kOe (Ns = 2), (K) 1.41 kOe (Ns = 1), and (L) 1.43 kOe. The bright spots represent skyrmions obtained by direct Lorentz TEM imaging, and dotted circles in J and K are used to guide the eye. (M) The quantized phase transitions between Ns = 6 and Ns = 5 cluster states. (N) The transitions between Ns = 2 and Ns = 1 cluster states. (O) The phase diagram in H space. The indicator “Ns = 6/5” represents the jumping state between Ns = 6 and Ns = 5 states, and so forth. Credit: Xuebing Zhao, et al. (2016) Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks. Proc Natl Acad Sci USA 113 (18) 4918-4923. Magnetic skyrmions, or noncoplanar swirling spin textures, are particle-like spin configurations with an integer topological charge that promise faster, denser memory storage. The hurdle to overcome in creating such devices is being able to understand single skyrmions in patterned nanoelements – but despite theoretical progress, real-world experimental studies of these entities have remained elusive. Recently, however, scientists at Chinese Academy of Science, Hefei, Fudan University, Shanghai, Nanjing University, Nanjing, and University of New Hampshire, Durham have demonstrated the direct visualization of skyrmion cluster states having different geometrical configurations in iron-germanium nanodisks. (Iron-germanium, or FeGe, is a complex alloy whose magnetic properties can vary considerably at nanoscale dimensions.) The researchers conclude that their results have an immediate implication for designing future skyrmion-based devices. Fig. S1. Schematic procedure for fabricating FeGe nanodisks by using the FIB-SEM dual-beam system (Helios NanoLab 600i; FEI) equipped with a GIS, and Omniprobe 200+ micromanipulator. The whole process is shown schematically in eight steps for A–I: (A) Following the standard TEM specimen preparation procedure (40), a thin FeGe sheet with a thickness of ∼1 μm was carved on the surface of a polycrystalline FeGe bulk using the FIB milling technique. (B) The FeGe sheet was cut into circular columns with different diameters by FIB using annular patterns. (C) Using the GIS system, a layer of amorphous PtCx was deposited on the FeGe columns by the electron beam-assisted chemical vapor deposition technique. This PtCx coating works as protection of the FeGe nanocolumns for nanomanipulation processes and also reduces the Fresnel fringe at the edge of the disk for the Lorentz TEM study. (D) Further deposition of amorphous PtCx layer by ion beam-assisted chemical vapor deposition to fasten the samples. (E) A U-shaped cut was made from the sheet by FIB milling. (F) The sheet of FeGe nanocolumns surrounded by amorphous PtCx was transferred to a clean surface of silicon and laid down by an Omniprobe 200+ micromanipulator. (G) Using the standard TEM specimen preparation procedure, a slice consisting of FeGe nanodisks in various sizes was fabricated by FIB milling. (H) The slice was transferred to a TEM Cu chip using the micromanipulator, and then was thinned to the desired thickness. (I) TEM image of the nanodisk sample depicted in the dashed box in H. (Scale bar, 200 nm.) Credit: Xuebing Zhao, et al. (2016) Direct imaging of magnetic field-driven transitions of skyrmion cluster states in FeGe nanodisks. Proc Natl Acad Sci USA 113 (18) 4918-4923.last_img read more

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Study of bat vocalizations shows they are communicating with one another

first_img © 2016 Phys.org 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 have known for some time that most bats make a lot of noise when they congregate in their colonies—as the researchers report, this is certainly the case for Egyptian fruit bats—when they roost, they get very loud. But until now, it was not known if the bats were simply making random noises or if their calls served a specific purpose.To learn more about bat vocalizations, the researchers housed a colony for 75 days and recorded bat sounds and movements on video, capturing 15,000 vocalizations in all. They fed the sounds to a voice-recognition system normally used for human voice analysis configured to work on bat sounds and used it to pull out any meaning that might exist. The VR system was able to connect certain sounds made by the bats to certain social situations and interactions that could then be tied to interactions seen in the video. The researchers grouped the sounds into four main groups: arguing over food, mating and sleeping clusters, and differences of opinion regarding how close was too close when hanging around each other in the colony.The team reports that in many cases, they were able to identify which bat was making a given noise, and sometimes which bat the noisemaker was addressing. They noted also that the bats tended to change their tones when addressing members of the opposite gender. Much of the cacophony in a bat cluster, the researchers suggest, is bats voicing their annoyance with those in very close quarters around them. They also note that their study of bat vocalizing has not concluded—they still want to know if the vocalizations are something they are born with or if they learn as they grow. To find out, the team plans to study bats as they grow—and to learn more about vocalizations outside of the roost, they plan to affix tiny microphones to some of them prior to releasing them back into the wild. (Phys.org)—A trio of researchers with Tel Aviv University has found that when Egyptian fruit bats make noises in their colonies, they are actually communicating with one another. In their paper published in the journal Scientific Reports, Yosef Prat, Mor Taub and Yossi Yovel describe their study of 22 captive bats for over two months and what recordings of them revealed. Journal information: Scientific Reports Egyptian Fruit Bat (Rousettus aegyptiacus) in flight. Taken at Rothschild Boulevard, Tel Aviv, Israel. Credit: Zoharby/Wikipediacenter_img More information: Everyday bat vocalizations contain information about emitter, addressee, context, and behavior, Scientific Reports 6, Article number: 39419 (2016) DOI: 10.1038/srep39419 , http://www.nature.com/articles/srep39419 Explore further Citation: Study of bat vocalizations shows they are communicating with one another (2016, December 23) retrieved 18 August 2019 from https://phys.org/news/2016-12-vocalizations.html Bats found to produce longer and more intense calls when crowded by other batslast_img read more

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Study tests how well humans interpret dog growls

first_imgCredit: CC0 Public Domain People have been living with dogs for a very long time, but, the researchers with this new effort wondered, have we learned to understand their communications? Other groups have studied barking in dogs and how people interpret them—in this new effort, the researchers sought to learn more about how well we humans understand what dogs are driving at when they growl.Growling in dogs is generally associated with aggressiveness, though growls are not always threatening—dogs often growl as part of their play, for example. To learn more about how well people are able to interpret dog growls, the researchers looked at how well they discern the differences between growls that occur during different activities such as when encountering a stranger (dog or human), defending a bowl of food, or when playing. They obtained recordings of dogs engaging in such activities and then played them individually for a group of volunteers—as growls were played, the researchers asked the volunteers to match the growl with a given activity.In all, the researchers asked 40 volunteers to listen to recordings of 18 dogs growling and to report which activity they felt was involved with each. They report that overall, the volunteers correctly matched the growl with the activity 63 percent of the time, which, they suggest, is well above guesswork. The researchers also found that women were better at reading the growls than men, guessing correctly 65 percent of the time, compared to just 45 percent for men. They also found that people who owned or worked with dogs regularly were better at reading the dog growls than those who did not by a margin of 60 percent to 40 percent. The volunteers were best at recognizing growls during play, but found it difficult to differentiate between growls associated with food guarding versus those associated with threat when encountering another dog. More information: T. Faragó et al. Dog growls express various contextual and affective content for human listeners, Royal Society Open Science (2017). DOI: 10.1098/rsos.170134 AbstractVocal expressions of emotions follow simple rules to encode the inner state of the caller into acoustic parameters, not just within species, but also in cross-species communication. Humans use these structural rules to attribute emotions to dog vocalizations, especially to barks, which match with their contexts. In contrast, humans were found to be unable to differentiate between playful and threatening growls, probably because single growls’ aggression level was assessed based on acoustic size cues. To resolve this contradiction, we played back natural growl bouts from three social contexts (food guarding, threatening and playing) to humans, who had to rate the emotional load and guess the context of the playbacks. Listeners attributed emotions to growls according to their social contexts. Within threatening and playful contexts, bouts with shorter, slower pulsing growls and showing smaller apparent body size were rated to be less aggressive and fearful, but more playful and happy. Participants associated the correct contexts with the growls above chance. Moreover, women and participants experienced with dogs scored higher in this task. Our results indicate that dogs may communicate honestly their size and inner state in a serious contest situation, while manipulatively in more uncertain defensive and playful contexts. Explore further Dogs can tell canine size through growls (Phys.org)—A team of researchers with Eötvös Loránd University in Hungary has conducted a study regarding how well humans interpret dog growls. In their paper published in Royal Society Open Science, the group reports on how well volunteers listening to taped dog growls correctly guessed the circumstances behind them.center_img Journal information: Royal Society Open Science © 2017 Phys.org Citation: Study tests how well humans interpret dog growls (2017, May 17) retrieved 18 August 2019 from https://phys.org/news/2017-05-humans-dog-growls.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

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Best of Last Year—The top Physorg articles of 2017

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 more promising news, a team with the International Potato Center conducted studies of their own, announcing that their indicators showed potatoes can grow on Mars. They ran a series of experiments aimed at figuring out if potatoes could grow under the conditions found on Mars—one of which involved planting a tuber in a CubeSat—with positive results. Another involved growing a potato in soil that was considered an analog of soil found on Mars.Meanwhile, another team announced that they had printed bricks from moon dust using the sun’s heat. The team working at the DLR German Aerospace Center started with raw material similar to lunar soil, then built a solar furnace to heat it to melt the soil grains—the result was an ink of sorts that could be used to print bricks for structures on the surface of the moon.And two researchers, one with UC Berkeley, the other with the Smithsonian Astrophysical Observatory, announced that they had found new evidence showing that all stars are born in pairs, which suggested that our own sun did as well (going as far back as 4.5 billion years ago). Back in April, Sarah Sadavoy and Steven Stahler reported on the results of creating and running statistical models based on evidence from a recent radio survey of a giant molecular cloud that was filled with relatively newborn stars.It was a good year for technology research, as well, as a team of scientists designed a solar cell that captured nearly all the energy of the solar spectrum—the team, working at George Washington University built a prototype that integrated multiple cells stacked as part of a single device. They report also that it used CPV panels, and was able to convert sunlight directly to electricity with 44.5 percent efficiency, though they acknowledge that it would be very expensive to produce commercially.Also, a team working at MIT announced that they had created a device that pulled water from dry air and was powered only by the sun. The device, the team reported, was made of a metal-organic framework which had been developed at the University of California. The group claimed it could pull water from the air in conditions as low as 20 percent humidity, though it still needed a lot of work to make it capable of absorbing more water.And a team at the University of Sydney claimed to have found a solution to the problem preventing zinc-air batteries from becoming mainstream—the difficulty in recharging them. They reported last summer that they had developed a three-stage method that could revolutionize rechargeability with zinc-air batteries. They claimed that their method could be used to create bifunctional oxygen electro-catalysts for building rechargeable zinc-air batteries from scratch.Also, a team with the Harvard John A. Paulson School of Engineering and Applied Sciences announced last winter that they had developed a long-lasting flow battery that could run for more than a decade with minimum upkeep. It worked, they reported, by storing energy in organic molecules dissolved in neutral pH water, which allowed for the construction of a nontoxic, non-corrosive battery with an exceptionally long lifetime.And a team at the University of Manchester announced that they had created a graphene sieve that could turn seawater into drinking water. The sieve utilized a graphene oxide membrane and was capable of sieving common salts. They reported that they had overcome problems such as membrane swelling with salt water exposure, and also came up with a way to control the pore size more precisely. They also reported that they were working on a way to make the system smaller.In other news, a team at Lund University published the results of a study they conducted regarding the things regular people can do to reduce climate change after finding that the most effective individual steps to tackle climate change weren’t being discussed—things like eating a plant-based diet, avoiding air travel, living car-free and having smaller families. They came to these conclusions by studying published papers and government reports, and found that such activities would have far more impact than changing light bulbs or recycling trash.Also, MIT professor Daniel Rothman published a paper claiming that mathematics predicted that by 2100, the oceans could hold enough carbon to launch the sixth mass extermination of species. He reported that he came to this conclusion after analyzing significant changes in the carbon cycle over the last 540 million years, including the five mass extinction events. He identified “thresholds of catastrophe” in the carbon cycle that, if exceeded, would lead to an unstable environment and ultimately, mass extinction.And a study led by Dr. Luca De Siena of the University of Aberdeen with a team from the INGV Osservatorio Vesuviano, the RISSC lab of the University of Naples, and the University of Texas at Austin led to locating a potential magma source in an Italian supervolcano. They described it as the first direct evidence of a so-called “hot zone” feeding a supervolcano. They reported that their evidence suggested that the volcano was nearing eruption.Also, a team with members from Germany and France’s European Synchrotron conducted a study surrounding the elements that are included in tattoo ink and found that nanoparticles from tattoos circulate inside the body—the first analytical evidence of the transport of organic and inorganic pigments and toxic element impurities in tattooed tissues, though it is still not clear if their presence causes problems.And a trio of researches, Paolo Bombelli, Christopher Howe and Federica Bertocchini reported finding caterpillars eating shopping bags, suggesting a biodegradable solution to plastic pollution. They reported finding the caterpillars chewing holes through bags by accident, and after a closer look, found the caterpillars were actually consuming and biodegrading the plastic. This, the team suggests, could point to a way to deal with the huge amounts of plastic garbage humans generate. Also, a team at Harvard announced that metallic hydrogen, once theory, became reality, as they found a way to create one of the rarest materials on the planet. To create the metal, the group squeezed hydrogen at 495 gigapascal forcing the molecules in it to break down and disassociate. They suggested their efforts could lead to answering some fundamental questions regarding the nature of matter.And a team of physicists at Washington State University announced that they had created “negative mass,” which, as they noted, behaved in surprising ways, such as accelerating backwards when pushed from a forward direction—it was created by using lasers to cool rubidium atoms to just above absolute zero and could be used to study challenging questions related to the cosmos.Also, a team at the University of Waterloo captured the first ‘image’ of a dark matter web that connects galaxies. The image was a composite of images gathered using weak gravitational lensing, and has helped confirm predictions that galaxies are tied together by dark matter.It was also a good year for space research, as a team at the University of New Mexico reported on a groundbreaking discovery that confirmed the existence of orbiting supermassive black holes. To confirm the discovery, the team measured the orbital motion between two supermassive black holes, both of which were hundreds of millions of light years from Earth—they used the U.S. based Very Long Baseline Array. The discovery, the team reports, was the culmination of 20 years’ worth of work.Also, a trio of researchers at the University of Edinburg dealt a blow to the possibility of colonizing Mars when they announced that their study of salt minerals on the Red planet killed bacteria—suggesting that the Martian surface is “more uninhabitable” than thought.” They exposed perchlorates similar to those on Mars to Bacillus subtilis cultures and then bathed them in ultraviolet light, causing the perchlorates to become active, which proved lethal for the bacteria. It was another great year for science, particularly physics, as evidenced by a study conducted by U.K., Canadian and Italian researchers who revealed substantial evidence of a holographic universe. They published what is believed to be the first observational evidence showing that the universe could, in fact, be nothing more than a vast and complex hologram. They came to this conclusion after investigating irregularities in the cosmic microwave background. Best of Last Week – New type of guitar string, looking for vanadium on Mars and US teens behind those of the 70s Citation: Best of Last Year—The top Phys.org articles of 2017 (2017, December 19) retrieved 18 August 2019 from https://phys.org/news/2017-12-yearthe-articles.html Explore further © 2017 Phys.org A sketch of the timeline of the holographic Universe. Time runs from left to right. The far left denotes the holographic phase and the image is blurry because space and time are not yet well defined. At the end of this phase (denoted by the black fluctuating ellipse) the Universe enters a geometric phase, which can now be described by Einstein’s equations. The cosmic microwave background was emitted about 375,000 years later. Patterns imprinted in it carry information about the very early Universe and seed the development of structures of stars and galaxies in the late time Universe (far right). Credit: Paul McFaddenlast_img read more

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Scientists are working on a pill for loneliness

first_imgAs a scientist, Stephanie Cacioppo has often viewed her life as an experiment. When John died, the practical elements of their joint research took on an urgent personal relevance. Read the whole story: The Guardian And yet we increasingly find ourselves isolated. Loneliness is no longer a powerful enough driver to break us out of the silos created by modern life. Like our insatiable love of high-calorie foods, what was once an adaptive tool has become so misaligned with the way we live that it’s causing, in the words of the former surgeon general Vivek H Murthy, an “epidemic”. It’s hard to compare our collective loneliness against that of previous generations, as we simply haven’t been measuring it consistently, but recent estimates suggest that anywhere from 22% to 75% of American adults are persistently lonely. A number of culture-wide structural changes might be to blame: more Americans live alone than ever before; fewer of us are marrying or having children; our average household size is shrinking. In many cases, these changes represent the availability of options where once the only accepted path was marriage and a nuclear family. But they also mean we are spending more time on our own. “Western societies have demoted human gregariousness from a necessity to an incidental,” writes John Cacioppo, a neuroscientist who studied social pain and passed away in March 2018, in his bookLoneliness. Loneliness is part of the human condition. A primeval warning sign, like hunger or thirst, to seek out a primary resource: connection. Millions of years of evolution have shaped us into creatures who need social bonds in the same way that we need food and water. The trouble is that chronic loneliness doesn’t just make you feel terrible – it’s also terrible for you. Loneliness elevates our risk of developing a range of disorders, including cardiovascular disease, neurodegenerative diseases, cognitive decline, and metastatic cancer. It also weakens the immune system, making us more susceptible to infections. Left untended, even situational loneliness can ossify into a fixed state that changes brain structures and processes, says Stephanie Cacioppo, director of the Brain Dynamics Lab at the University of Chicago Pritzker School of Medicine. She is also John Cacioppo’s widow and was his research partner up until his death last year.last_img read more

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Hes here to play it your way

first_imgNo serious plans this Friday night? Might as well make a slot for Nikhil Chinappa spinning out music live at a lounge in the Capital.Mixing commercial tunes, EDM and a bit of trance, basically all the music you could ask for in a night, Chinappa, one of the best known DJ’s in India (alongside his MTV VJ fame) and one of the forces behind Sunburn and submerge in India will surely keep the crowd entertained!Pen this one in for the weekend!DETAILWhere: Cocaine, GK 1When: 22 MarchTime: 9 pm onwardslast_img read more

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Political and crafty

first_imgInspired by the current socio-political scenario of India and by PM Modi’s Chai Pe Charcha, artiste Saudamini Misra has created a series of installations and sculptures.The Kettle (Harbinger of Achhe Din)- The rise of Narendra Modi from the humble beginning of a chaiwala to a national icon carrying the promise of better times, inspired this sculpture. The Kettle is an indispensable icon of Indian household that goes beyond the class strata. Rich, poor or middle class; the kettle is part of everyone’s life. The little clock signifies memories, progression and transition. Also Read – ‘Playing Jojo was emotionally exhausting’The Typewriter- This is a commentary on Indian authors who capitalise on the poverty of India by making it their ‘original’ subject, in order to win international acclaim. The irony is that the so called Indian author himself belongs to that privileged strata of Indian society where his financial well being affords him the time and luxury to write away his time. One Rupee Airplane: The wooden airplanes sculpted by Mishra take us beyond its work. Their inner energies reflect the growth of the country’s economy and that of bilateral trade. It is symbolic of the global economic nexus which is now becoming all the more conspicuous with the formation of the new government.last_img read more

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Ktaka election CM joins voice with Mayawati

first_imgKolkata: Chief Minister Mamata Banerjee on Thursday came out in support of BSP supremo Mayawati, who hit out at BJP after the saffron party formed the government in Karnataka and termed the entire episode as a conspiracy to destroy the Constitution.”I endorse the views of Mayawatiji. We must give full respect to the maker of our Constitution, Dr Babasaheb Ambedkar,” Banerjee tweeted. “It is a conspiracy to destroy the Constitution made by Baba Saheb Ambedkar. Since they (BJP) came to power, they have been misusing government machinery, thereby attacking democracy,” Mayawati had told reporters in New Delhi. The BSP chief was referring to BJP’s B S Yeddyurappa taking oath as the Karnataka Chief Minister. Also Read – Heavy rain hits traffic, flightsLaunching a scathing attack at BJP for the alleged “horse trading” to form its government in Karnataka, the Chief Minister appealed to the President of India to guide the country to save the democracy.Banerjee said: “As a protector of the Constitution, I appeal the President of India to please guide us and the country.”Stating that she has not complained of “horse-trading” against BJP only in one particular place, the Chief Minister said: “I don’t want to mention any name, it is bad for everyone. Whoever is doing it, we condemn it. Secondly, there are some discrepancies and discrimination.”In the same breath, she criticised what is happening in Karnataka, stating it is different from what had happened in Goa and Manipur, where Congress was the single largest party. “We always respect democracy. Today somebody may come to power and tomorrow they may not continue. But if you violate the Constitution and the democratic system, then please remember it leaves an effect on all,” she said.last_img read more

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Negligence whiff in Mangolpuri fire 2 dead

first_imgTwo persons including a five-year-old girl were killed, as 15 others suffered burn injuries after a major fire broke out in the wee hours in Outer Delhi’s Mangolpuri area.Three brothers lived with their families in a three-storey building in close proximity and all the three residences were gutted in the incident.The fire initiated from the house of Deen Dayal, in which his five-year-old daughter Gayatri and his sister-in-law Surekha (28) were killed. Deen Dayal’s mother – Maya and brother,  Bhupender suffered severe burn injuries and they have been referred to Safdarjung Hospital for treatment. Those injured, include four children. Also Read – Company director arrested for swindling Rs 345 croreThe other severely injured are being treated at Sanjay Gandhi Memorial Hospital; however, some of them were discharged after first aid. “We have registered a case under Section 304A IPC (causing death by negligence) in this connection and further investigations are on,” said a senior police official.According to the fire department, the fire broke out around 3.38 am, following which 10 fire tenders were rushed to the spot.“The cause of fire seems to be a short circuit. The families used to make mats at their house; the sparks fell on the raw material stashed in the residences, causing the fire to spread quickly,” he added. Also Read – Man who cheated 20 women on matrimonial websites arrestedMeanwhile, Tata Power Delhi Distribution Limited (TPDDL) offered deep condolences and sympathies to the families of the deceased and those injured in the accident. “It seems that the fire incident broke out due to unauthorised storage of inflammable wooden mesh in the area. TPDDL safety team officials reached the spot within 10-15 minutes of the incident and helped in relief and rescue,” said Ajay Maharaj, dead of department, corporate communication.He further added that TPDDL’s team has checked the location and confirmed that the fire did not break out due to any fault in TPDDL’s network. However, the exact cause of fire could not be ascertained then.last_img read more

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17yrold footballer gets electrocuted after touching lightpost

first_imgKolkata: A 17-year-old footballer died after being electrocuted when he accidentally touched a lightpost situated at a corner of a playground at Madhyamgram in North 24-Parganas on Sunday evening. Police said the victim, Ajay Sarkar, was a local resident.He was well known in the area for his football skills and he used to play for different local clubs.On Sunday evening, he went to a playground in the area along with his brother, to play football. After playing a match, Ajay went to a corner of the playground to collect something when he accidentally touched a lightpost. He was electrocuted and immediately fell on the ground. Other players and some local people went to the spot hearing Ajay’s cry and found him senseless.They took him to Madhyamgram Rural Hospital, where he was declared brought dead. A pall of gloom descended in the area with the death of Ajay.People who were present in the ground, said that there was no delay in taking him to the hospital. Local people demanded necessary steps to ensure that no such incident takes place in the area in future.A lot of such unfortunate accidents happen when live wires are touched leading to deaths. Throughout the city, the civic authorities are taking enormous steps to check if there are faults and live wires strewn on roads and pavements. At the same time, elaborate measures have been taken to check the condition of such lightposts in the area.Incessant showers have led to several electrocutions in the city as well.last_img read more

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Straight from the loom

first_imgIn an attempt to promote Indian handlooms and to bring out the best of handloom products that India has to its credit, an exhibition of Indian handlooms titled ‘The First Home of India Handloom Brand Products’ was inaugurated by Santosh Kumar Gangwar, Minister of State for Textiles (independent charge), in the presence of Babul Supriya Baral, Minister of State for Urban Development Housing and Urban Poverty Alleviation and Kirron Kher, Member of Parliament, at Central Cottage Industries Emporium in the national Capital on Tuesday.  Also Read – ‘Playing Jojo was emotionally exhausting’The cottage brings out authentic and good quality products from Indian Handloom Brand (IHB) drawn from some of the exotic locations of India are on display and sale. The products range from sarees including Chanderi, Mangalagiri, Venkatagiri, Balrampuram, Maheshwari, Kota Doria, Pochampalli, Tangail, Chettinad, Banaras Tanchoi silk, Banarasi Buti silk; fabrics such as Banaras Tanchoi silk, Banaras Cut-Work, Plain Tussar, Ikat, Pochampalli; Kullu shawls and Pochampalli bedspreads will be available at the exhibition.  Also Read – Leslie doing new comedy special with NetflixThe showcased collections are made using textiles from across India to create a unique identity and promote the rich Indian culture and heritage. This is part of a continued initiative by the IHB to promote Indian handloom. The main focus is to retain the sanctity of the traditional hand-woven textiles while molding the styles for a more contemporary look.Present at the inauguration were Rashmi Verma, Secretary, Ministry of Textiles; Alok Kumar, Development Commissioner, Handloom, Ministry of Textile; Pramod Nagpal, Managing Director, CCIC of India Ltd. During the occasion Santosh Kumar Gangwar, Minister of State for Textiles (independent Charge) said, “India has a very rich cultural heritage and I want to bring forth Indian Handloom Brand to the entire country with presenting a trendy garment segment, besides readymade products, stoles, shawls and home furnishing made of handloom fabrics. “In order to make handloom products more relevant in the current scenario it becomes imperative to produce good quality, defect-free handloom fabrics with good colour fastness that do not contain harmful dyes. “There is also a need to widen the range of products in offer to cater to a larger audience, especially the youth, which today has access to fashion from across the globe. The Indian handloom industry has a glorious past and we are committed towards the resurgence of hand-woven textile and also the weavers, whose welfare and development remains our key focus.”India Handloom Brand was launched by Prime Minister on August 7, 2015. The main objective is to promote the production of quality products with new designs for winning the trust and confidence of customers by giving particular attention to the defect free, hand woven, authentic niche products with zero defect and zero impact on environment.last_img read more

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Bailey bridge levelcrossing to be operational at last from today

first_imgKolkata: The bailey bridge on Chetla Canal and the level-crossing that will connect the Behala-New Alipore side with Alipore, will be operational from Friday morning.The work for the bridge and the level-crossing and repair of the thoroughfares connecting the two sides has been completed in a record time of 20 days, with close coordination between the state Public Works Department (PWD) and Eastern Railways.”Small and medium vehicles from the Behala-New Alipore side will travel towards the Alipore side initially. After the Pujas, Kolkata Police will experiment regarding both way movement,” said a senior official of the PWD department. Also Read – Rain batters Kolkata, cripples normal lifeThe bridge, along with the level-crossing, is connecting the southward extension of Alipore Avenue with Block G in New Alipore, from where it would move some 600 metres to connect with Humayun Kabir Sarani.”The bailey bridge and the level-crossing are very much capable of both way movement of traffic. So, we can also have movement from Behala-New Alipore side to the Alipore side,” a senior official of Kolkata Police’s traffic department said.A senior official of Eastern Railway (ER) said that the level-crossing gate between New Alipore and Majerhat Station in Sealdah-Budge Budge line will be an alternative route for vehicle movement. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killed”To ensure smooth road and rail movement, 6 pairs of EMU locals in the Sealdah-Budge Budge section will remain suspended from Saturday, until further advice. Running of all Up and Down Sealdah South–Nangi Passenger Special will also remain cancelled from Friday,” the official said.He added that out of seventy existing services, 52 services will continue in Sealdah (South)–Budge Budge section. A cabin has already been created and manpower has been put in place by ER for operating the level-crossing. The walkway for pedestrians adjacent to Majerhat Bridge over Chetla Canal will also be operational from Friday. Hume pipes have been placed and its upper portion has been concretised for the crossover. “The state has taken up the matter with the Railways for a similar kind of path for vehicle movement at this place. Permission has not been granted by the Railways but negotiations are on,” an official said.For a two-lane road, the width needs to be at least 7 metres and for this, a highrise on the New Alipore side needs to be pulled down. “If the Railways give us the nod, we are hopeful of convincing the residents to relocate after arranging proper rehabilitation for them,” he added.last_img read more

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Unhappy marriage good for diabetic men Study

first_imgAn unhappy marriage may actually slow the development of diabetes in men and promote successful treatment once they do get the disease, suggests an interesting study. It may be because wives are constantly regulating their husband’s health behaviours, especially if he is in poor health or is diabetic. And while this may improve the husband’s health, it also can be seen as annoying and provoke hostility and emotional distress. “The study challenges the traditional assumption that negative marital quality is always detrimental to health,” said lead investigator Hui Liu, associate professor of Sociology at Michigan State University in the US. Also Read – ‘Playing Jojo was emotionally exhausting’“It also encourages family scholars to distinguish different sources and types of marital quality. Sometimes, nagging is caring,” Liu said.Diabetes requires frequent monitoring that the wives could be prodding the husband, boosting his health but also increasing marital strain over time.Using data from the US National Social Life, Health and Aging Project, Liu and colleagues analysed survey results from 1,228 married respondents over five years.  At the onset of the study, the respondents were 57 to 85 years old –389 had diabetes at the end of the study. The researchers investigated the role of marital quality in diabetes risk and management and found two major gender differences. Also Read – Leslie doing new comedy special with NetflixThe most surprising finding was that, for men, an increase in negative marital quality lowered the risk of developing diabetes and increased the chances of managing the disease after its onset. For women, a good marriage was related to a lower risk of being diabetic five years later. Women may be more sensitive than men to the quality of a relationship and thus more likely to experience a health boost from a good quality relationship, Liu said.The findings appeared in the Journals of Gerontology Series B: Psychological Sciences and Social Sciences. This thought-provoking study helps to understand the dynamics of companionship, which results in fights out of love and affection, for the partner. The frank and aggressive (at times) behaviour helps the partner push their spouse to take care of themselves. And, also people acknowledge the concern and even if it is out of fear, they take care of themselves.last_img read more

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Obesity speeds up puberty onset in boys

first_imgBoys with obesity, or excess belly fat, enter puberty at an earlier age than average, scientists have found. Researchers from the University of Chile conducted the study on 527 Chilean boys ages four to seven years. They found that both total body obesity and central obesity, or excess belly fat, were associated with greater odds of starting puberty before age nine. “With the increase in childhood obesity worldwide, there has been an advance in the age at which puberty begins in girls,” said Maria Veronica Mericq, the lead investigator of the study. Also Read – Add new books to your shelf”However, in boys the evidence has been controversial,” said Mericq. Some studies have found that obesity delayed puberty, whereas another study showed that only overweight but not obesity induced earlier puberty in boys. Early puberty — called precocious puberty — is linked to possible problems including stunted growth and emotional-social problems, researchers said. The team found that the prevalence of total obesity increased with age, from 22 per cent of boys ages 6 to 7 years to 28.6 per cent at 11.4 years, the average age at onset of puberty for this group. Also Read – Over 2 hours screen time daily will make your kids impulsiveCentral obesity also increased in that timeframe, from 11.8 per cent to 17.4 per cent. Precocious puberty reportedly occurred in 45 boys, or nine per cent. Total obesity and central obesity from ages four to seven raised the odds of early puberty compared with having a healthy weight. For instance, among boys age five or six, those with obesity had nearly 2.7 times the odds of starting puberty early, and those with central obesity had almost 6.4 higher odds of puberty before age nine, Mericq said. She explained that central obesity more closely relates to fat mass, because a higher BMI may reflect increased muscle, especially in athletes. “Early puberty might increase the risk of behaviour problems and in boys could be related to a higher incidence of testicular cancer in adulthood,” Mericq said.last_img read more

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CM to take part in Save Green Stay Clean rally today

first_imgKolkata: Chief Minister Mamata Banerjee will take part in a rally on the theme of ‘Save Green Stay Clean’, on Thursday. The rally will start from Birla Planetarium and end at Nazul Mancha in Ballygunge Lake. Members of different NGOs working in the field of environment protection, school and college students and people from all walks of life will take part in the rally. At Nazrul Mancha, Banerjee will distribute saplings.The state government has already taken measures to conserve water and July 12 will be celebrated every year as Save Water Day. The Panchayats and civic bodies have been instructed not to lift ground water rampantly as the ground water level has dropped in many areas. The state government is also giving stress on rainwater harvesting. The Chief Minister had joined a rally on July 12 on the theme of ‘Save Water Save Life’, from Jorasanko thakurbari to Gandhi statue on Mayo Road. In the administrative review meetings, Banerjee has repeatedly asked the district administration to take measures to conserve the environment and to ensure that the waterbodies are not being filled up.last_img read more

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