first_img Citation: Entropyman.org Explains Why Pots ‘Unbreak’ on the Nanoscale (Video) (2009, February 16) retrieved 18 August 2019 from https://phys.org/news/2009-02-entropymanorg-pots-unbreak-nanoscale-video.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. It may just be a neat camera trick, but the Web site explains that – in terms of Newton’s laws – nothing was supernatural or wrong about that picture. Rather, the reason why we don’t see broken objects “unbreaking” in everyday life is due to the Second Law of Thermodynamics. If you’ve ever wondered just what the Second Law means – beyond the fuzzy idea about disorder always increasing – you may want to check out the rest of Entropyman.org. The site is the brainchild of Edward Feng, a former Miller Fellow at UC Berkeley who now works at Sandia Livermore National Laboratory, specializing in statistical mechanics. Feng designed Entropyman.org as an outreach project to explain to a general audience how entropy works.”I created this outreach project to explain the principles behind the biggest advance in my field over the last decade,” Feng told PhysOrg.com. “This theory explains how life is different on the nanoscale and a pot can unbreak. This can happen because of the smallness of the pot. These principles are the foundation for my research with Gavin Crooks on time’s arrow and other topics in statistical mechanics.”As Feng explained, the background to this project began at the Miller Symposium, a yearly get together for the Miller Institute.”There was a session on how newspapers were losing funding for science stories, and the culprit was the internet,” he said. “Well, I thought this was a little harsh. Besides, wasn’t the internet a new medium to convey science, with pictures and movies? That’s when I decided to embark on this project. With financial support from the Miller Institute, I hired a film maker, and the rest is history.”Entropyman.org discusses how single molecules, such as an RNA molecule, can stretch and shrink. Because RNA molecules are so small, they result in a much smaller entropy increase than larger objects. The larger the entropy increase, the less likely the object will take a time-reversed path with a decrease in entropy. Because a ceramic pot or tile has a large entropy gain when breaking, the ratio of increasing entropy to decreasing entropy is very high, so an entropy decrease is much less likely to be observed. In other words, it’s extremely unlikely that a broken pot will put itself back together, while a molecule could.Explaining these concepts in terms of bank accounts, wedding rings, and the Eiffel Tower, Entropyman.org hopes to enable general readers to understand why pots spontaneously self-assemble on the nanoscale and, while it’s possible that your room will become clean while you lounge on the couch, it is incredibly unlikely. To see the site, visit http://entropyman.org.© 2009 PhysOrg.comcenter_img Edward Feng, a researcher at Sandia Livermore National Laboratory, has created a new Web site called Entropyman.org to explain the Second Law of Thermodynamics (PhysOrg.com) — A man lifts his hand in the air, and broken pieces of ceramic lying on the sidewalk spring up into his hand, coming together to form a flower pot. He lifts his hands again, and more broken pieces spring together to make a square ceramic tile.last_img read more

first_img(Phys.org)—The eye, whether in humans or other animals, is truly one of nature’s most sophisticated advancements, able to convert light into signals the brain can interpret as imagery, all in real time. Most of the actual work is done at the back of the eye where rods and cones, two types of photoreceptors are located. Cones are primarily responsible for the eye’s sensitivity to color, while rods, which are far more numerous (some 120 million exit in one human eye), are more sensitive to light in general. To find out just how sensitive rods are, researchers in Singapore have been studying single rod photoreceptors taken from an African Clawed Frog, and have found, as they describe in their paper published in Physical Review Letters, that such rods are able to discern and count single photons and are also able to determine the coherence of very weak pulses of light. © 2012 Phys.org Journal information: Physical Review Letters To study the rods, the team used a tiny pipette that was able to hold a single rod and that also contained a liquid solution that simulated its natural environment to keep it alive. They then placed a very small laser just in front of it and shot the rod with pulses of light. Because the pipette and solution also served as an electrode allowing for measurements, the researchers were able to measure how much current was produced by the rod in response to the pulses of light.Each rod has at its tip a segment that contains rhodosin photopigment, a substance that changes chemically in the presence of light. When no light is present, a constant current of ions flows in and out; when light is detected however, some of the current is altered causing the cell to be polarized resulting in the creation of an electrical signal that is sent via the optic nerve to the brain.In the study, the team fired a rapid succession of laser pulses at the rod and found it able to discern, i.e. measure, individual differences of up to 1000 photons per pulse. They also found that the rods were able to tell the difference between coherent light (the degree to which the waves are in phase) and “pseudothermal” light, where the waves are chopped up by a rotating disk, to such an extent that the researchers believe they will be able to serve as a model for creating highly sensitive artificial detectors.In the end, the researchers found that single rhodopsin molecules are able to interact with single photons, a finding that demonstrates just how sensitive rods truly are; so much so that further studies by the team will look at their use in quantum optics and communication. (Left) Structure of a rod cell in the retina. Photons absorbed in the outer segment cause a rearrangement of rhodopsin molecules, which initiates a sequence of chemical events resulting in excitation of an optic nerve signal. (Right) Microscope image of the fiber taper and a suction micropipette with the constrained rod cell. The cell response to photons is measured with the pipette, which acts as a micro electrode. Credit: Physics Synopsis, DOI: 10.1103/Physics.5.103 Explore furthercenter_img Citation: Researchers find retinal rods able to detect photon number distribution (2012, September 14) retrieved 18 August 2019 from https://phys.org/news/2012-09-retinal-rods-photon.html Bright lights, not-so-big pupils More information: Measurement of Photon Statistics with Live Photoreceptor Cells, Phys. Rev. Lett. 109, 113601 (2012) DOI: 10.1103/PhysRevLett.109.113601AbstractWe analyzed the electrophysiological response of an isolated rod photoreceptor of Xenopus laevis under stimulation by coherent and pseudothermal light sources. Using the suction-electrode technique for single cell recordings and a fiber optics setup for light delivery allowed measurements of the major statistical characteristics of the rod response. The results indicate differences in average responses of rod cells to coherent and pseudothermal light of the same intensity and also differences in signal-to-noise ratios and second-order intensity correlation functions. These findings should be relevant for interdisciplinary studies seeking applications of quantum optics in biology. 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

first_img Most people have seen video of microorganisms in motion, some have short filaments known as cilia that cover their outer edges causing movement of the organism or the fluid in which they exist. Others such as the unicellular microalga Chlamydomonas reinhardtii, have longer appendages known as flagella, which are flexible rods protruding from the front of the body. C. reinhardtii uses its two flagella to swim through liquid, breaststroke style, which means the appendages must be synchronized—but what mechanism allows this synchronization to occur? Scientists do not know but have suspected it has to do with hydrodynamic forces, meaning the movement of the fluid causes it to come about. In this new effort, the researchers report that experiments they have carried out suggest such assumptions have been wrong, and that the synchronization comes about at least in part due to contractile fibers that connect the two flagella together.The first experiment conducted by the team consisted of placing C. reinhardtii samples in a pipette and then filming the microorganisms as the liquid in which they were swimming inside was sloshed back and forth at varying intensities. The team reports that the flagella initially synchronized with the flow of the fluid, but only up to a point, at which it could not keep up as the slosh rate was increased. They noted also that the rate at which the flagellum beat individually in isolation from its normal partner varied by amounts up to 30 percent, but the two still synchronized when working together. They then calculated that if hydrodynamic forces alone were causing the synchronization, the flagella would have to produce a flow 30 times the normal swim speed of the microorganism to account for such a difference, thus, such forces do not appear to be the answer.The team also looked at mutant samples of C. reinhardtii which did not have a band of contractile fibers connecting the flagella inside their bodies as is normal for the algae and found the flagella did not synchronize. This they claim, suggests that the fibers are somehow causing or allowing the synchronization to occur. Unless they crane their necks all sperm would only turn left More information: Greta Quaranta et al. Hydrodynamics Versus Intracellular Coupling in the Synchronization of Eukaryotic Flagella, Physical Review Letters (2015). DOI: 10.1103/PhysRevLett.115.238101ABSTRACTThe influence of hydrodynamic forces on eukaryotic flagella synchronization is investigated by triggering phase locking between a controlled external flow and the flagella of C. reinhardtii. Hydrodynamic forces required for synchronization are over an order of magnitude larger than hydrodynamic forces experienced in physiological conditions. Our results suggest that synchronization is due instead to coupling through cell internal fibers connecting the flagella. This conclusion is confirmed by observations of the vfl3 mutant, with impaired mechanical connection between the flagella. Explore further © 2015 Phys.org (Phys.org)—A team of researchers with Delft University in the Netherlands has found via lab experiments, that synchronization that occurs with algae flagella while they swim is likely not driven by hydrodynamic forces. In their paper published in Physical Review Letters, the researchers describe their experiments and observations and why they believe that what they saw helps explain how flagella synchronization in microorganisms works in general. Marco Polin with the University of Warwick in the U.K. offers a Viewpoint piece on the work done by the team in the same journal issue.center_img Citation: Study suggests synchronization of algae flagella while swimming not driven by hydrodynamic forces (2015, December 8) retrieved 18 August 2019 from https://phys.org/news/2015-12-synchronization-algae-flagella-driven-hydrodynamic.html Journal information: Physical Review Letters (a) Experimental setup. (b) Snapshots representing the stroke patterns of C. reinhardtii, for a cell with f0=54.3  Hz and an external flow with fF=52.7  Hz and UF=±527  μm.s−1. Time between snapshots: 6 ms. Arrows represent the direction of the background flow. In this sequence, the flagella beat with the flow and the flagellar tip motion has the same direction as the external flow. (c) Snapshots of same cell as in (b) 0.33 s later. The flagella beat against the flow. Credit: (c) Physical Review Letters 115, 238101 (2015). DOI: 10.1103/PhysRevLett.115.238101 . Used with permission. 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

first_img More information: Measuring the Distribution and Excitation of Cometary CH3OH Using ALMA, arXiv:1602.03488 [astro-ph.EP] arxiv.org/abs/1602.03488AbstractThe Atacama Large Millimeter/submillimeter Array (ALMA) was used to obtain measurements of spatially and spectrally resolved CH3OH emission from comet C/2012 K1 (PanSTARRS) on 28-29 June 2014. Detection of 12-14 emission lines of CH3OH on each day permitted the derivation of spatially-resolved rotational temperature profiles (averaged along the line of sight), for the innermost 5000 km of the coma. On each day, the CH3OH distribution was centrally peaked and approximately consistent with spherically symmetric, uniform outflow. The azimuthally-averaged CH3OH rotational temperature (Trot) as a function of sky-projected nucleocentric distance (ρ), fell by about 40 K between ρ=0 and 2500 km on 28 June, whereas on 29 June, Trot fell by about 50 K between ρ=0 km and 1500 km. A remarkable (∼50 K) rise in Trot at ρ=1500-2500 km on 29 June was not present on 28 June. The observed variations in CH3OH rotational temperature are interpreted primarily as a result of variations in the coma kinetic temperature due to adiabatic cooling, and heating through Solar irradiation, but collisional and radiative non-LTE excitation processes also play a role. © 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. Citation: Scientists measure methyl alcohol emission from comet C/2012 K1 (PanSTARRS) (2016, February 22) retrieved 18 August 2019 from https://phys.org/news/2016-02-scientists-methyl-alcohol-emission-comet.html ALMA confirms comets forge organic molecules in their dusty atmospheres Explore further For their measurements, the researchers employed the Atacama Large Millimeter/submillimeter Array (ALMA), located in the Atacama desert, Chile. ALMA, thanks to its unprecedented resolution and sensitivity, was previously used to study the distributions of HCN (hydrogen cyanide), HNC (hydrogen isocyanide) and H2CO (formaldehyde) in the inner comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON). Now, the facility obtained new information on the distribution and temperature of methanol in the inner coma of comet C/2012 K1 (PanSTARRS). The observations were conducted on June 28-29, 2014, when the comet was very bright (magnitude 8.5), visible through a small telescope and even binoculars, and relatively near Earth at a distance of nearly two astronomical units (AU).”ALMA was used to obtain measurements of spatially and spectrally resolved CH3OH emission from comet C/2012 K1 (PanSTARRS). (…) Detection of 12-14 emission lines of CH3OH on each day permitted the derivation of spatially-resolved rotational temperature profiles (averaged along the line of sight), for the innermost 5,000 km of the coma,” the scientists wrote in a research paper.C/2012 K1 (PanSTARRS) is an Oort cloud comet that was discovered on May 17, 2012 using the Pan-STARRS telescope located on the island of Maui in Hawaii. The comet came to perihelion on Aug. 27, 2014 at a distance of 1.05 AU from the sun. Thus, the summer of 2014 offered astronomers a great chance to observe this icy planetesimal in detail.Comets are believed to be frozen leftovers from the formation of the solar system around 4.5 billion years ago. They are relatively pristine and therefore may hold clues to how the solar system was made. Finding an organic compound like methanol on a comet hints that these icy bodies could have been a source of the complex organic molecules necessary for life.Methanol, thanks to its abundance in comets and its complex energy level structure is an easily detectable molecule for probing the cometary coma temperature at radio and submillimeter wavelengths. ALMA observations of methanol emission at millimeter and submillimeter wavelengths have permitted Cordiner’s team to conduct the first instantaneous, spatially resolved 2-D measurements of the coma’s rotational temperatures. They detected large variations in the methanol rotational temperature in C/2012 K1 (PanSTARRS) over distances of about 1,000 kilometers (sky-projected distance), likely caused by changes in the coma kinetic temperature, mainly due to adiabatic cooling, and heating through solar irradiation.”This study demonstrates that spatial temperature variations may need to be considered when deriving coma molecular abundances from spectral line data,” the researchers concluded.The scientists called for further high resolution observations and modelling that could yield better information about the coma thermal physics and molecular excitation, and assist in more accurate determination of cometary compositions. They also also emphasized that there is still a lack of understanding concerning the physical and chemical structure of the near-nucleus cometary coma at distances less than a few thousand kilometers from the nucleus. (Phys.org)—An international team of researchers led by Martin Cordiner of NASA’s Goddard Space Flight Center has conducted measurements of CH3OH (methanol) emission from comet C/2012 K1 (PanSTARRS) that could yield invaluable information about cometary compositions and provide insights on the formation of our solar system. The results were published online on Feb. 16 in the arXiv journal. NEOWISE series of infrared images of comet C/2012 K1 (PanSTARRS) on May 20, 2014. Credit: NASA/JPLlast_img read more

first_imgPerhaps that is what drove artiste Manu Singh to explore the elemental imaginary landscapes which look like water, earth or sky.Wings, Shadows and 1000 Birds, a solo exhibition of paintings was showcased at Triveni Kala Sangam.  Works on display were full of large canvas paintings that explore imaginary background and landscapes. These works involve more obfuscation of the Imaginary large wings, shadows and 1000 birds using oil and other elements as mediums. Also Read – ‘Playing Jojo was emotionally exhausting’As the artiste says ‘I’ve always been drawn to ‘wings’ since I was a child. The wings are symbol of aspiring to the greatest heights of accomplishment. Wings (white in color) stands for clarity of mind, and how clean mental focus combined with stable footing can transform our lives in magical ways.My works 1000 Birds represent joy, harmony, ecstasy, balance, and love. It denotes a sunny outlook in life, spiritual freedom and psychological liberation. Each of us has a shadow that whispers stories of our own self-defeating fears to us. My work shows how understanding our own shadow side can lead us to lives of tremendous realization and peace.’ Also Read – Leslie doing new comedy special with NetflixThe artiste says she wanted to see how far he could can push reality to the other side where the ‘real’ is still recognisable, but start becoming partially surreal.She wanted to see how far he can push both the real and the surreal at the same time into one another, building that tension until they are just one and the same.Most canvases are black and white paintings with a modern touch, in that the strokes explore movement while the grey field stays constant most of the time. She has experimented with supports as well as with medium.last_img read more

first_imgKolkata: The residential plots sold through e-auction in Action Area II in New Town by Housing Infrastructure Development Corporation (HIDCO), has evoked great response with one plot being sold for Rs 57 lakh per cottah.Twenty two out of 25 plots have already been sold and e-auction for the remaining three plots will be held on May 2. The highest price received so far is Rs 343 lakh for a 6 cottah plot. The average price for a cottah of land in the remaining 22 plots stands at Rs 38-39 lakh. The area of the plots measuring 5 cottah will be e-auctioned on May 2. These plots will be leased out for 99 years. Also Read – Heavy rain hits traffic, flightsHIDCO had decided to sell 100 plots in2017. Of these, 75 plots have been sold through lottery and the remaining 25 plots will be sold through e-auction. The first online booking for 75 plots began on January 28 in presence of Firhad Hakim, the state Urban Development minister.There were around 4,000 applicants for the 75 plots. Of the 75 plots, 58 plots were meant for individual houses, while the remaining 17 plots were meant to set up housing cooperatives. Of the 58 plots, 25 were reserved for people belonging to the middle income group (MIG) and the remaining 33 plots were for the people belonging to the higher income group (HIG). The area of the plots varied between 2.5 cottah and 5 cottah. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe population of New Town is 1 million, with 0.5 million additional floating population.New Town is a green city, where various steps have been taken to increase the green cover and conserve energy. The waste water is being recycled to water the roadside trees. Over the years, New Town has come up as an educational hub, with several private and state-run universities constructing their second campus there. It is the IT hub of Kolkata and has come up fast as a cultural centre as well. New Town is also the country’s first township, where cycle sharing scheme has been introduced and is becoming immensely popular. There are graded paths for bicycles. New Town also houses the country’s biggest convention centre.There had been several complaints against allotment of plots during the Left Front regime. The people were kept in the dark regarding the price of the plots. After coming to power in 2011, Chief Minister Mamata Banerjee had abolished the chairman’s quota and made a bureaucrat the chairman of HIDCO. The lottery to allot plots was also conducted maintaining clarity.last_img read more

first_imgThe artist belong to various Indian state and the medium used are oil, acrylic, water, charcoal or mixed. Each one of them deal with subjects that are  close to their heart and imagination. Participating artists are Banoj Mohanty, Austin Konchira, Deepali Mangalik, Dinesh kumar panwar, Padmini Mehta, Rajeev Semwal, Rajni Kiran Jha, Sahil Jain, Surendran Karthyayan, Saru S, seshadri, Sunita Lamba from different states.The exhibition will be held from December 21- 27 at the Lalit Kala Bhawan, Ravindra Bhawan Tansen Marg. Also Read – ‘Playing Jojo was emotionally exhausting’The chief guest for the evening will be professor Sudharshan  Seneviratne(High Commissioner of Sri Lanka in India).Few of the work are like storytelling (narrative) in which the artist tell a lot without saying a word. It is through their imagination skill, they creates a whole cycle of image formation or any sensation in the mind of a viewer. Sunita Lamba the organiser is a well known artist who has won a won a gold medal for her sculpture at the Beijing Olympics. She has that acumen to delve into human consciousness. Austin Konchira artist trained under the instruction of artist Mahindra, a renowned painter in Kerala, bring richness to figuration and abstraction in bright colors and versatile contours. Banoj Mohant’s works depict social message and idealism in society which is rare and missing. Lots of creative thinking has gone in to get the right message conveyed. Also Read – Leslie doing new comedy special with NetflixDeepali Mangalik a nature enthusiast was raised in Dehra Dun and being surrounded by beautiful flora and fauna, her surroundings are her inspiration. Dinesh displays vivid cultural heritage in his work of art showcasing impressionistic rural scenes that focuses on one moment or gives a intelligent impression about a character, idea, setting, or object. Padmini from Varanasi (Banaras), grew up surrounded by holy images, grassy meadows and towering trees that bring out the richness of the city while Rajeev’s drawings help him in expressing his feelings. Black is his favorite color and it brings out his creativity with just one color. Rajni’s Matsya- Kanya series includes the Matsya- Kanya and Lotus. Fish is the symbol of good luck. Whereas lotus is symbolic of peace and prosperity. In the Hindu religion girl is considered as goddess Laxmi.S  Seshadri an engineer but has been wielding the brushes as a hobby while Sahil Jain is a contemporary artist who owns both theory and technique . A deep thinker who strives to peel off the layers from the different faces around him and has the potential to see the real behind the facades.last_img read more