Motioncapture helping reveal how kangaroos hop

first_img The researchers, Dr Alexis Wiktorowicz-Conroy of the Royal Veterinary College in London and colleagues in the US and Australia, used an array of outdoor cameras at the Alma Park Zoo in Brisbane, Queensland, to record reflected infrared light from highly reflective ball markers stuck onto the fur of kangaroos. High-speed video cameras were also used to record the movements.The same kind of motion-capture technology is used in sports studies such as analyzing golfing swings, and has also been used in movies such as the Lord of the Rings to translate the motions of actors onto animated creatures. The technology is usually used indoors to avoid the infrared light from the sun, but the fiber-optics company Vicon developed a motion capture system that can be used outdoors and allowed the researchers to borrow the equipment.The researchers also had the kangaroos hop on a series of force plates, which measured the forces exerted by the kangaroo’s feet onto the ground.One aim of the research is to understand how kangaroos change their body posture and the mechanics of their hopping in different sized species of kangaroo. Many animals become more upright as their body size increases, but kangaroos do not. At slow speeds kangaroos use their tail rather like a fifth limb, but at faster speeds they hop and can bounce along at high speeds and long periods without changing posture and apparently without fatigue.Dr Wiktorowicz-Conroy said the team want to understand how even large and heavy kangaroos can hop so fast and not change posture. Scientists have not yet been able to explain how large kangaroos can do this without their bones breaking. She said other scientists were looking at their ankle joints but their research was focusing more on the other joints in the hind limbs.The infrared motion capture system records the same kind of data that can be obtained by analyzing high-speed film frame by frame, but does it automatically. The system has provided the researchers with large amounts of data, which they are currently analyzing. Dr Wiktorowicz-Conroy said the data should help them solve at least some of the biomechanical puzzles and increase their understand more about animal location and especially hopping.Their preliminary findings show the kangaroos’ movement is highly efficient at conserving energy, and they use their tails as a counterbalance while hopping, which reduces the energy expended. Citation: Motion-capture helping reveal how kangaroos hop (2011, March 11) retrieved 18 August 2019 from https://phys.org/news/2011-03-motion-capture-reveal-kangaroos.html (PhysOrg.com) — Scientists in Australia, the UK and US have for the first time used infrared motion capture technology outdoors to work out how kangaroos distribute their weight and the forces as they hop along. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. © 2010 PhysOrg.com Explore further Australian kangaroo cull prompts outragelast_img read more

Researchers construct a model of impact for El Nino La Nina events

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. (Phys.org) —A small team made up of researchers from the U.S. and Europe has constructed a model that helps map parts of the world that are most at risk of flooding due to El Niño/La Niña events. In their paper published in Proceedings of the National Academy of Sciences, the team describes how they compared weather data over the past half century with economic impacts of actual floods to create a model that may soon be used to help predict flooding events in the future. Explore further By now, most everyone has heard about El Niño/La Niña weather events— El Niño is where warm water west of South America causes more rain to fall in some places. La Niña is where the same waters are cooler than normal resulting in different changes to rain patterns. Perhaps less well known is that such events have a worldwide impact, causing more flooding than normal in some parts of the world and less in others. Oftentimes the flooding that occurs results in damage to property and loss of life, thus it would be a good thing if forecasts could be made, warning people in areas most at risk. Unfortunately, up till now, such forecasts have not been available because such events don’t always cause the same types of flooding in the same places. In this new effort, the researchers sought to provide a model for building such a forecasting ability by using data over a long period of time.The research team obtained weather data for the years 1959 to 2000, pulling out periods of El Niño/La Niña weather events which they then compared with reports of damage due to flooding. Next they compared those results with flood reports during normal times and used what they found to create a model. The model showed that during El Niño events, 34 percent of the Earth’s surface had higher or lower than normal amounts of flooding—that number jumped to 38 percent for La Niña weather events.The model also showed which parts of the planet are more susceptible on average, to flooding due to such events. The Southwest in the U.S. for example and parts of South America, both experience more flooding during El Niño events, while places like the Sahel in Africa, and most of Australia experience less.The research team acknowledges that their model is still in its infancy but believe that over time, as more research is conducted, it will improve to the point that it will be useful in helping areas prepare for flooding during El Niño/La Niña weather events. Different types of El Nino have different effects on global temperature More information: Strong influence of El Niño Southern Oscillation on flood risk around the world, PNAS, Philip J. Ward, DOI: 10.1073/pnas.1409822111AbstractEl Niño Southern Oscillation (ENSO) is the most dominant interannual signal of climate variability and has a strong influence on climate over large parts of the world. In turn, it strongly influences many natural hazards (such as hurricanes and droughts) and their resulting socioeconomic impacts, including economic damage and loss of life. However, although ENSO is known to influence hydrology in many regions of the world, little is known about its influence on the socioeconomic impacts of floods (i.e., flood risk). To address this, we developed a modeling framework to assess ENSO’s influence on flood risk at the global scale, expressed in terms of affected population and gross domestic product and economic damages. We show that ENSO exerts strong and widespread influences on both flood hazard and risk. Reliable anomalies of flood risk exist during El Niño or La Niña years, or both, in basins spanning almost half (44%) of Earth’s land surface. Our results show that climate variability, especially from ENSO, should be incorporated into disaster-risk analyses and policies. Because ENSO has some predictive skill with lead times of several seasons, the findings suggest the possibility to develop probabilistic flood-risk projections, which could be used for improved disaster planning. The findings are also relevant in the context of climate change. If the frequency and/or magnitude of ENSO events were to change in the future, this finding could imply changes in flood-risk variations across almost half of the world’s terrestrial regions.center_img Journal information: Proceedings of the National Academy of Sciences © 2014 Phys.org The 1997 El Nino seen by TOPEX/Poseidon. Credit: NASA Citation: Researchers construct a model of impact for El Nino / La Nina events (2014, October 21) retrieved 18 August 2019 from https://phys.org/news/2014-10-impact-el-nino-la-nina.htmllast_img read more

Supercomputer study shows Lambda baryon a type of quark molecule

first_img Scientists have learned over the years that subatomic particles can link or bond together in ways that are similar to atoms in molecules. One such particle Λ(1405) has been the focus of much research and discussion among physicists as it has defied the description of a typical baryon (a subatomic particle with a mass greater than or equal to a proton and which exist as a nucleon or hyperon)—they are supposed to have three quarks. Instead, they have shown behavior that suggests a molecule-like structure consisting of a quark pair and a triplet—prior research has shown that it takes less energy to cause it to be excited than should be the case for three quarks bound together, suggesting that there is something else at play, such as extra quarks. The apparent oddity has had physicists debating its nature for over half a century.Particles that have quarks are typically divided into two categories, two-quark mesons and three-quark baryons. Some researchers in the past had theorized that Λ(1405) particles could be actually be a combination of mesons and baryons which would result in a particle “molecule” with five quarks. In this new study, the researchers ran simulations of quark interactions (using algorithms based on lattice quantum chromodynamics) on a supercomputer that appears to confirm that theory—they found a magnetic moment of zero when calculating the quark contribution to the particle, which suggested instances of a meson (antikaon) coupled to a baryon—the first such example of a meson-baryon molecule.The research by the team builds on the efforts of others who have recently suggested other types of couplings (such as two mesons) might occur. The researchers believe further research will reveal other meson-baryon pairings as well that until now have been thought to be unique types of baryons. More information: Lattice QCD Evidence that the Λ(1405) Resonance is an Antikaon-Nucleon Molecule, Phys. Rev. Lett. 114, 132002 – Published 1 April 2015. dx.doi.org/10.1103/PhysRevLett.114.132002 . On Arxiv: arxiv.org/abs/1411.3402ABSTRACTFor almost 50 years the structure of the Λ(1405) resonance has been a mystery. Even though it contains a heavy strange quark and has odd parity, its mass is lower than any other excited spin-1/2 baryon. Dalitz and co-workers speculated that it might be a molecular state of an antikaon bound to a nucleon. However, a standard quark-model structure is also admissible. Although the intervening years have seen considerable effort, there has been no convincing resolution. Here we present a new lattice QCD simulation showing that the strange magnetic form factor of the Λ(1405) vanishes, signaling the formation of an antikaon-nucleon molecule. Together with a Hamiltonian effective-field-theory model analysis of the lattice QCD energy levels, this strongly suggests that the structure is dominated by a bound antikaon-nucleon component. This result clarifies that not all states occurring in nature can be described within a simple quark model framework and points to the existence of exotic molecular meson-nucleon bound states. © 2015 Phys.org Journal information: arXiv , Physical Review Letters (Phys.org)—A team of researchers with the University of Adelaide and the Australian National University has found that the excited state of the Lambda baryon, Λ(1405), is actually a type of quark molecule. In their paper published in the journal Physical Review Letters, the researchers describe how they ran simulations on a computer that confirmed the properties of the unique particles. How CERN’s discovery of exotic particles may affect astrophysics Explore further Citation: Supercomputer study shows Lambda baryon a type of quark molecule (2015, April 6) retrieved 18 August 2019 from https://phys.org/news/2015-04-supercomputer-lambda-baryon-quark-molecule.html The quark-mass dependence (mq∝mπ2) of the lowest-lying Λ(1405) states observed in our lattice QCD calculations is illustrated by the discrete points at each of the pion masses available in the PACS-CS ensembles. The low-lying energy spectrum of our Hamiltonian model (solid curves) constrained to the lattice QCD results (discrete points) is also illustrated. The associated noninteracting meson-baryon basis states are illustrated by the dashed curves and the vertical dashed line indicates the physical pion mass. Credit: Phys. Rev. Lett. 114, 132002 – Published 1 April 2015. DOI: 10.1103/PhysRevLett.114.132002 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

Physicists investigate fundamental limits of quantum engines

first_img Physicists Obinna Abah and Eric Lutz at the Friedrich-Alexander University Erlangen-Nürnberg in Germany have published a paper on the energy-efficient quantum machines in a recent issue of EPL. Abah is currently a Royal Commission for the Exhibition of 1851 research fellow at Queen’s University in Belfast, UK.The performance of any kind of engine—quantum or classical—is largely determined by its energy efficiency (the ratio of energy output to energy input) and its power (the rate of energy output in a given time). Conventional thermodynamics imposes a tradeoff between an engine’s efficiency and its power—meaning when you increase one, the other decreases. For quantum engines, however, it’s possible to increase both the efficiency and the power at the same time. This means that, with the proper methods, quantum engines can potentially produce more energy output from a given amount of energy input, and do so at a faster rate than before the improvement.Some of the methods that allow for the simultaneous increase in efficiency and power are called “shortcut-to-adiabaticity” techniques. Adiabatic transformations are highly desirable because they dissipate little energy, which increases the efficiency of the system and speeds up the system’s dynamics, which increases the system’s power output. As their name implies, shortcuts to adiabaticity allow quantum machines to mimic adiabatic operation in a much shorter time than is possible using genuine adiabatic transformations, which are infinitely slow. Although previous research has demonstrated the advantages of shortcuts to adiabaticity for enhancing the performance of heat engines, these methods typically do not account for the energy cost of the shortcut protocol when calculating the final efficiency of the system. As a result, the efficiency improvements due to shortcuts to adiabaticity appear to be for free, exaggerating their effects.In the new study, Abah and Lutz developed a method for evaluating the performance of a system that accounts for the energy cost of these shortcuts. Their results show that shortcuts to adiabaticity enhance the performance of a system only if the shortcut is sufficiently fast, since faster shortcuts have lower energy costs. On the other hand, very slow shortcut protocols have higher energy costs that may exceed any potential energy gains. “Our work shows that higher efficiency and higher power may be achieved at the same time with the help of shortcut-to-adiabaticty methods, even when the energetic cost of the shortcut is taken into account,” Abah told Phys.org.The physicists also showed that there is a fundamental limit to the efficiency of any quantum engine, no matter what kind of shortcuts to adiabaticity it uses. Surprisingly, the limits on a quantum engine are stricter than the limits imposed by the second law of thermodynamics, which sets the ultimate limits on the efficiency of classical engines. As the physicists explain, the reason for the tighter bounds on quantum engines is because classical mechanics does not place restrictions on the speed of a process, whereas quantum mechanics does have speed restrictions, which are given by “quantum speed limits.” The scientists plan to compare different shortcut methods in order to determine the one leading to the most energy-efficient machine. Understanding quantum speed limits and their fundamental limitations on quantum systems is essential for designing future quantum engines.”The advent of miniaturization will unavoidably lead to machines that are so tiny that their dynamics will generally obey the laws of quantum mechanics instead of those of classical mechanics,” Abah said. “Their properties will then be governed by quantum thermodynamics.” Citation: Physicists investigate fundamental limits of quantum engines (2017, August 4) retrieved 18 August 2019 from https://phys.org/news/2017-08-physicists-fundamental-limits-quantum.html Explore further More information: Obinna Abah and Eric Lutz. “Energy efficiency quantum machines.” EPL. DOI: 10.1209/0295-5075/118/40005 © 2017 Phys.org Journal information: Europhysics Letters (EPL)center_img Quantum shortcuts cannot bypass the laws of thermodynamics (Phys.org)—Quantum engines are known to operate differently than—and in some cases, outperform—their classical counterparts. However, previous research on the performance of quantum engines may be overestimating their advantages. In a new study, physicists have developed an improved method to compute the efficiency of quantum engines. They show that the ultimate efficiency of quantum systems is subject to tighter fundamental limits than those imposed by the second law of thermodynamics, which governs the efficiency of classical systems. A quantum engine in which work is produced during the first and third strokes. Credit: Abah et al. ©2017 EPL 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

Hemimastigotes found to represent a major new branch on evolutionary tree of

first_img Long-term study shows atmospheric biome fluctuates by season A team of researchers at Dalhousie University has found evidence that suggests hemimastigotes represent a major new branch of evolutionary life. In their paper published in the journal Nature, the group describes their genetic study of the dirt-dwelling microbe. Journal information: Nature The researchers note that hemimastigotes have been known to scientists since the 19th century, but it was not until very recently that technology has allowed scientists to learn how different they are from other eukaryotic life forms. The researchers report that one of their team members, Yana Eglit, had been digging in a local park just outside of Halifax. Intrigued by the microbes she found in the dirt, she isolated a group that appeared to be hemimastigotes. After letting the microbes reproduce in a small dish filled with nothing but dirt and water for a month, she collected samples that the team used to conduct a genetic analysis.The researchers report that the hemimastigotes are so different from anything observed before that fungi and animals are actually more closely related. They describe the microbes as being approximately two-hundredths of a millimeter long—they move using over a dozen flagella. And they survive by eating other microbes. It was the latter characteristic that led the team to name the species Hemimastix kukwesjijk, in honor of a hairy man-eating ogre from Mi’kmaq (native people in Nova Scotia) folklore.The researchers describe hemimastigotes as representing a major new branch on the evolutionary tree—standing above the level of a kingdom. The team was able to analyze hundreds of samples, thanks to Eglit’s efforts in getting them to reproduce, which provided a very clear understanding of the genetic makeup of the microbes. They also suggest their findings fill some evolutionary holes in the tree of life. They also note that in addition to learning about how different hemimastigotes truly are from other life forms, the work by Eglit also offers a lesson for other researchers in how to grow such species in large enough volume to allow for such thorough study. More information: Gordon Lax et al. Hemimastigophora is a novel supra-kingdom-level lineage of eukaryotes, Nature (2018). DOI: 10.1038/s41586-018-0708-8 © 2018 Science X Networkcenter_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. Explore further Citation: Hemimastigotes found to represent a major new branch on evolutionary tree of life (2018, November 15) retrieved 18 August 2019 from https://phys.org/news/2018-11-hemimastigotes-major-evolutionary-tree-life.html Credit: CC0 Public Domainlast_img read more

Game for pain Heres how to benefit from it

If getting inked is on your mind, the India International Tattoo convention [IITC] is just the right place for you. In its second year now, the show puts up the latest trends, fashion and techniques in tattoo art. Seminars, training as well as demonstrations are scheduled combined with lots of music, get togethers, parties, food and fun for the participants and tattoo families. It provides a platform for all tattoo professionals across the country. ‘There are around 40 to 50 tattoo artistes who have come together to learn at this convention. The inter-country participation at the event is a great learning experience. One of the major advantages is that the skills and techniques of the art gets upgraded,’ said Aditi Naithani, a participant and a tattoo artiste.‘Tattooing as an art is interesting. It requires physical labour coupled with mental concentration. Once you indulge in it, you are transfered beyond the tangible and the audible. The more exposure you have, the more your artistic skills grow and conventions like these help to achieve that,’ added the 28-year-old.DETAILAt: Surajkund, FaridabadOn Till: 7 OctoberTimings: 11am- 7.30 pm read more

CESC restores all electrical faults within two days of norwester

first_imgKolkata: CESC has managed to repair all electrical faults within its jurisdiction by Thursday. Ever since the Nor’wester hit the city and its adjoining areas in the evening of April 17, the employees of the CESC acted promptly and worked on a war footing to control the situation.CESC power supply was disrupted specially in areas where the city is served by overhead wires. The city’s underground cables remained largely unaffected. However, a number of cases were reported where lamp posts belonging to other agencies were also affected due to storm. Also Read – Heavy rain hits traffic, flightsAccording to a senior official of CESC, after a long time, so many faults had taken place during the storm. In first 24 hours after the incident, CESC received altogether 36,000 telephone calls from different parts of the city and adjoining areas.CESC had carried out repair works in Howrah’s Belur area on Thursday morning. Amongst the worst affected areas were Northern and Eastern parts of the city, including Patuli, Panchasayar, Survey Park, Lake Town, Bangur, Dum Dum, Kamarhati, Khardah, Sodepur, Howrah and Serampore.According to the CESC spokesman: “Works were done on a day-and-night basis, which had enabled the agency to bring the situation under control within the next day. In most of the cases, the normalcy was restored within Wednesday afternoon.last_img read more