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 (PhysOrg.com) — Scientists have been studying how krill form into superswarms, which are among the largest gatherings of living creatures on Earth. Krill swarm. Photographer: Jamie Hall. Image source: NOAA. via Wikimedia Commons. Antarctic krill provide carbon sink in Southern Ocean Citation: Krill ‘superswarm’ formation investigated (2009, October 13) retrieved 18 August 2019 from https://phys.org/news/2009-10-krill-superswarm-formation.html Juvenile krill (small crustaceans resembling shrimps) gather in their trillions in the Southern Oceans to form superswarms. In the Antarctic, for example, one species of krill (Euphausia superb) forms superswarms that stretch for tens of kilometers. Until recently, no one has understood why or how they do it. So scientists with the British Antarctic Survey (BAS), led by Cambridge (UK) researcher Dr Geraint Tarling, decided to try and find out. The team used echo-sounding equipment to study over 4500 different swarms of krill in the Scotia Sea, a massive area that lies between South Georgia Island and the Antarctic Peninsula. The report, published in the journal Deep Sea Research I, described how the research team discovered there are two types of swarm: small swarms composed of adult krill, and large swarms composed of juveniles. The small swarms may be only around 50 meters long and four meters deep, and are not densely packed (about 10 krill per cubic meter). The large swarms are the “superswarms”, which can stretch for many kilometers and are about 30 meters deep. The superswarms are much denser, with up to 10 times more individual krill per cubic meter.This was the opposite of the result expected by Dr Tarling and his team, who thought the small swarms would be dense and the superswarms more diffuse. Dr Tarling said he was astonished at the density of the superswarms and the concentration into a small area of such a massive amount of biomass.The BAS team also discovered that the large swarms tended to form when there was less food available, but the reasons for the formations of superswarms were unclear. Dr Tarling said a likely explanation is that a large swarm gives an individual protection from predators such as seals and whales, and a large swarm can confuse predators. It can also be more energy efficient, which could help juveniles grow more quickly.The trade-off in forming large swarms is much greater competition for food, and this could explain why adult krill form less densely packed swarms, since they are more negatively buoyant than juveniles, and have to expend more energy in swimming. They need more food than the juveniles, and benefit from less competition.Another finding of the research that was opposite to the expectation was that superswarms are more likely to occur at night. It was previously believed this would be less likely, since krill feed at night.The habit of forming superswarms containing trillions of juveniles means that most of the young krill in the Antarctic Ocean are likely to be in just a few superswarms. This means krill may be much more susceptible to overfishing than thought previously since fishing fleets can locate and catch entire swarms. In doing so, they may be wiping out most of the krill in the Southern Oceans, and hence endangering everything else in the food chain that depends on them.More information: Variability and predictability of Antarctic krill swarm structure, Geraint A. Tarling et al., Volume 56, Issue 11, November 2009, Pages 1994-2012, doi:10.1016/j.dsr.2009.07.004© 2009 PhysOrg.com
(PhysOrg.com) — In information processing, physicists are often in search of ways to turn classical strategies into quantum ones, with the implication that the quantum version is somehow stronger, faster, or more secure than its classical counterpart. However, quantum strategies do not always perform better than classical ones. As a case in point, a new study has compared the strength of classical and quantum correlations in a simple number guessing game and found no difference in performance. Further, the physicists found that a third form of correlations – post-quantum correlations – could outperform both quantum and classical forms. Post-Quantum Correlations: Exploring the Limits of Quantum Nonlocality More information: Mafalda L. Almeida, et al. “Guess Your Neighbor’s Input: A Multipartite Nonlocal Game with No Quantum Advantage.” Physical Review Letters 104, 230404 (2010). DOI: 10.1103/PhysRevLett.104.230404 Copyright 2010 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. 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 their study, Mafalda Almeida from the ICFO-Institut de Ciencies Fotoniques in Barcelona and coauthors found that classical and quantum correlations performed equally in a game called “Guess Your Neighbor’s Input.” The game involves a group of players in a ring who each receive an input number of either 0 or 1. The point of the game is that each player tries to guess the number of the person to their right. Of course, players are not allowed to know any information about their neighbor’s numbers before guessing, nor to communicate after having received their numbers. In order to win the game, players are allowed to share physical resources, such as classical or quantum correlations. Importantly, all these resources must be “no-signaling”; that is, they cannot enable instantaneous communication.The no-signaling principle is fundamental for physicists dealing with the concept of nonlocality. In nonlocality, one object can influence another object at a distance, such as through entanglement. However, this phenomenon cannot be used to send information faster than light, which prevents a direct conflict with Einstein’s theory of relativity. Nonlocal correlations, which physicists define as those violating a Bell inequality, are important because they serve as a key resource for quantum information processing.However, in the game in this study, the researchers found that players gained no advantage at guessing the correct numbers by using quantum resources compared to classical ones. This makes sense, since it seems that players should require signaling in order to improve their guessing accuracy, and neither quantum nor classical correlations involve signaling.Yet when the physicists looked at what happened when the players use no-signaling correlations (that is, correlations that satisfy the no-signaling principle) that are even stronger than those allowed in quantum mechanics (i.e. they had a higher degree of violation of a Bell inequality), they did find a surprise. No-signaling correlations could actually outperform the quantum and classical correlations, suggesting that quantum correlations obey a stronger version of the no-signaling principle.“Our study highlights a fundamental difference between quantum correlations and certain post-quantum correlations (that is, correlations stronger than those allowed in quantum mechanics, but which nevertheless obey the no-signaling principle),” Nicolas Brunner, coauthor and a physicist at the University of Bristol, told PhysOrg.com. “This is significant because it strongly indicates that quantum correlations could obey a stronger version of the no-signaling principle.”This game is the first that involves entanglement among more than two bits (called “multipartite entanglement”) to identify some of the boundary (or gap) between quantum correlations and the stronger no-signaling correlations. However, the results also raise further questions, such as what kind of physical principle might limit quantum non-local correlations? Why do (theoretical) post-quantum correlations seem to not exist in nature? And if they did exist, could these correlations be used for other information tasks? Right now, these questions are likely a long way from being answered. Citation: Quantum guessing game reveals insight into stronger-than-quantum correlations (2010, June 22) retrieved 18 August 2019 from https://phys.org/news/2010-06-quantum-game-reveals-insight-stronger-than-quantum.html Explore further
(PhysOrg.com) — If a plan to build new 4G mobile phone base stations in the US goes ahead, engineers say GPS satellite navigation systems will be seriously jammed and huge areas of the country will become GPS dead zones. Explore further © 2010 PhysOrg.com Virginia company LightSquared communicates with satellites using low-power signals in the frequency range 1525 to 1559 MHz, which is close to the frequency range GPS uses (1559 to 1610 MHz). So far this has not caused interference problems but if the planned 40,000 new high-power 4G base stations are built they would use stronger signals in the same frequency range.LightSquared hopes to complete the 4G broadband network by 2015 at a cost of up to $8 billion. The network is expected to deliver mobile phone users download speeds of up to 10 megabits per second.Engineers Scott Burgett and Bronson Hokuf with Garmin International, a satellite navigation systems manufacturing company in Olathe, Kansas, say the stronger signals will be disastrous, seriously limiting GPS reception, causing widespread GPS jamming and depriving vast areas of the US of GPS coverage.The engineers carried out laboratory testing on a portable GPS device and a general Federal Aviation Administration (FAA)-certified aviation receiver. A Spirent GSS 6560 simulator representing the current configuration of 31 GPS satellites was used to simulate the GPS signals. The LightSquared transmission signal was simulated by a Rhode and Schwartz signal generator and amplified to produce the required signal strength.The results were that the GPS began to experience interference when 5.8 km or closer to the simulated LightSquared transmitter and lost the fix altogether when 1.1 km away. Interference started at 22.1 km for the aviation receiver, and total loss of fix occurred at 9.0 km from the transmitter.The US air force is also concerned about the interference. General William Shelton, head of the US Air Force Space Command, said at a recent Air Warfare Symposium in Orlando that if LightSquared’s network goes ahead and GPS systems are jammed we should “think about the impact.” He said he was hopeful a solution could be found but LightSquared had to prove they could operate without interfering with GPS.LightSquared spokesman Jeff Carlisle said the base stations are not at fault, but the problem could arise because some GPS receivers may be able to “see into” the neighboring frequency at which LightSquared operates. He said the company has already spent $9 million on a series of filters to prevent its current signals from interfering with the weak GPS signals, and if a problem will exist with the new network only some highly sensitive GPS receivers will be affected.LightSquared was given a provisional permit late last year by the US Federal Communications Commission (FCC), but the permit stipulated that the network should not cause interference with other signals.Burgett and Hokuf forwarded their report to the FCC on January 19. LightSquared is now required to submit an initial plan for working with federal agencies and GPS companies to determine how to deal with interference. The plan is due at the FCC by February 25, and a final report is due on June 15. LightSquared cleared to offer wireless broadband Citation: New 4G network could cause widespread GPS dead zones (2011, February 23) retrieved 18 August 2019 from https://phys.org/news/2011-02-4g-network-widespread-gps-dead.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.
Citation: New offshore turbine design to create and store energy (2011, September 28) retrieved 18 August 2019 from https://phys.org/news/2011-09-offshore-turbine-energy.html Explore further SeaTwirl, according to the company website, is a “new principle to store and harvest offshore wind energy. SeaTwirl uses the ocean sea water as a bearing and can therefore use cheaper and heavier materials and function as a large low speed flywheel.” This new design will allow wind power generating plants to be built without the need for a gearbox, transmission line or roller-bearings. (PhysOrg.com) — While many are taking to the oceans and trying to find the best ways to harness offshore wind and provide clean energy from renewable sources, the basic design of any wind turbine is that of a windmill. That is until now. The new design in the works is by Ehrnberg Solutions AB, which is owned and operated by Daniel Ehrnberg. Ehrnberg is also the inventor behind this newly designed turbine called SeaTwirl. © 2011 PhysOrg.com More information: seatwirl.com/technology/the-principlevia IEEE Spectrum The new turbine, according to their video, is designed to be better suited for the ocean environment and use the benefits of both the air and the water. While the biggest prototype to date is 1:50 to scale, Ehrnberg hopes to have a fully functional turbine in the next four to six years and believes the SeaTwirl technology will be much more cost-effective. He plans to use undersea cables that are currently in place to bring the energy back to shore. Vertiwind: Floating wind turbine project launched 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.
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. Gorilla Glass is currently estimated to be in use by over a billion and a half devices the world over, and has become a household name. Its strength and resistance to scratching in addition to its very low weight has made it an ideal candidate for touch-screen devices. Corning makes the glass using a propriety chemical process that causes more than the normal number of ions to be introduced into the glass, adding to its strength and reducing the likelihood of cracking. Also, like the glass currently used in automobiles, it’s more likely to crack than shatter when subjected to extreme stress or impact.Evenson told those in attendance at the Summit that using Gorilla Glass in a car would cut down on the weight of the vehicle. Also, engineers could distribute the weight reduction in a way that would slightly alter the car’s center of gravity. Together, he explained, that would help cars with the new window glass gain a few extra miles out of each gallon of fuel. He also noted that because of the unique nature of Gorilla Glass, cars that used it as a replacement for current glass would be much quieter inside the cabin.Evenson also suggested that he expects at least one high-end car maker to begin using Gorilla Glass in at least some of its vehicles as early as next year, though he wouldn’t say which it was. He also briefly spoke about progress being made on a project he called microbiological glass, which he said, would kill bacteria on contact. He followed that by discussing another new product the company is working on called Willow Glass—a bendable type of glass that he said is currently about as thick as a dollar bill. He said its introduction will likely lead to the creation of hundreds of new devices. (Phys.org) —Corning Senior Vice President, Jeffrey Evenson told audience members at this year’s MIT Technology Review’s Mobile Summit, that its Gorilla Glass will very soon be used in automobiles. Currently, Gorilla Glass is used as part of a touch-screen for hand-held devices—from phones to tablet computers. Using the glass in automobiles Evenson said, would allow for better gas mileage and noise suppression. ‘Gorilla Glass’ maker looks beyond smartphones Citation: Corning VP says Gorilla Glass headed for automobiles (2013, June 12) retrieved 18 August 2019 from https://phys.org/news/2013-06-corning-vp-gorilla-glass-automobiles.html © 2013 Phys.org Explore further More information: via MIT Tech Review
Journal information: Nature In this new effort the researchers analyzed data collected from 1,750 sheep and found that there is a third category of sheep, those that have one type of each allele—they get the benefits of both—the live longer than the sheep with the biggest horns and mate more often than the sheep with tiny horns. This, the researchers suggest, explains why big horns haven’t become predominant—though they may lead to producing more offspring in the short time, those with smaller horns win out in the end by breeding over more seasons. Thus, natural selection results in splitting the difference to ensure the best chance of survival for the species as a whole.The researchers note that the same allele exists in both humans and mice, and has been found to be involved in bone density and sexual development. They suggest more research will need to be conducted to discern if the gene is a factor in either longevity or successful procreating in either species Soay is a small breed of bighorn sheep—they live in mountainous terrain on an island called Hirta and have what would appear to be a genetic anomaly. Some of the males have extremely large horns, while the horns of others are much smaller. Because research has shown that the males that have the larger horns are much more successful at mating, there is the question of why all the males don’t have large horns.To find out, a team working in a prior effort studied the genes of the sheep and discovered a particular allele (alternative forms of the same gene) responsible for horn size, called Ho. The sheep all have two of them—those sheep that have two of the large-size variant have large horns, while those with two of the small size variant had small or even no horns at all. But there was a catch. Sheep with smaller horns, for reasons that aren’t yet known, tend live longer. Three rams on the island of Hirta, St Kilda with different horn morphologies. The male on the left displays the scurred (vestigial) phenotype, meaning that it cannot compete with the normal-horned males for access to mates during the rut. Credit: Peter Korsten Citation: Researchers unlock genetic twist in differences in horn size with sheep (2013, August 22) retrieved 18 August 2019 from https://phys.org/news/2013-08-genetic-differences-horn-size-sheep.html Explore further More information: Life history trade-offs at a single locus maintain sexually selected genetic variation, Nature (2013) DOI: 10.1038/nature12489AbstractSexual selection, through intra-male competition or female choice, is assumed to be a source of strong and sustained directional selection in the wild. In the presence of such strong directional selection, alleles enhancing a particular trait are predicted to become fixed within a population, leading to a decrease in the underlying genetic variation. However, there is often considerable genetic variation underlying sexually selected traits in wild populations, and consequently, this phenomenon has become a long-discussed issue in the field of evolutionary biology. In wild Soay sheep, large horns confer an advantage in strong intra-sexual competition, yet males show an inherited polymorphism for horn type and have substantial genetic variation in their horn size6. Here we show that most genetic variation in this trait is maintained by a trade-off between natural and sexual selection at a single gene, relaxin-like receptor 2 (RXFP2). We found that an allele conferring larger horns, Ho+, is associated with higher reproductive success, whereas a smaller horn allele, HoP, confers increased survival, resulting in a net effect of overdominance (that is, heterozygote advantage) for fitness at RXFP2. The nature of this trade-off is simple relative to commonly proposed explanations for the maintenance of sexually selected traits, such as genic capture (‘good genes’) and sexually antagonistic selection. Our results demonstrate that by identifying the genetic architecture of trait variation, we can determine the principal mechanisms maintaining genetic variation in traits under strong selection and explain apparently counter-evolutionary observations. Soay ram on the island of Hirta, St Kilda. Credit: Arpat Ozgul Dome-headed dinosaurs did more than just butt heads © 2013 Phys.org (Phys.org) —A team of researchers from the U.K. and Australia, working with sheep data obtained from a small island off the coast of Scotland has learned why it is that some sheep have large horns, while others do not. In their paper published in the journal Nature, the team describes how they studied data obtained over a 20 year period to discover the seeming contradiction with the sheep. 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.
Artist’s impression of SS 433. Credit: NASA The only known supercritical accretor in the Milky Way galaxy is SS 433, a highly exotic eclipsing binary star system. Its primary object is likely a black hole. Its secondary companion is believed to be a late A-type star based on its light spectrum. The secondary in SS 433 is losing mass into an accretion disk as it spirals in toward the primary, which is slowly consuming it. In turn, as the accretion disc spirals in toward the primary, it becomes super-heated and emits intense X-rays. Physicists are fascinated by the exotic nature of SS 433, but also by its strong resemblance to ultraluminous X-ray sources (ULXs), which are astronomical sources of X-rays that are less luminous than the nuclei of active galaxies, but are more luminous than any known stellar process. These are sources of X-rays that exceed the Eddington luminosities of neutron stars and stellar black holes. Recently, a group of researchers from Russia and Japan have compared the optical spectra of ULXs to SS 433 and have determined that ULXs with X-ray luminosities of ~1040 erg S-1 must constitute a homogenous class of objects that most likely have SCADs. They have published their results in Nature Physics. The most popular models for ULXs have either intermediate mass black holes with standard accretion disks or stellar-mass black holes with accretion disk luminosity exceeding the Eddington limit. Based on X-ray data alone, it is not possible to distinguish these models, so the researchers have turned to optical spectroscopy to find unique information about ULXs. Using the 8.2 meter Subaru Telescope of the National Astronomical Observatory of Japan, located at the Mauna Kea Observatory on Hawaii, they obtained high-quality spectroscopic data from a number of ULX sources.They have determined that ULX spectra are quite similar to late nitrogen Wolf-Rayet stars (WNLs), which exhibit broad emissions of ionized nitrogen and helium or carbon. They have very high surface temperatures and produce intense stellar winds. The spectra from ULXs also resemble those of luminous blue variable stars (LBVs) in the compact stages of stellar development. Because the physical conditions of its disk wind may be similar to WNL stars, SS 433 also bears a strong resemblance to ULXs. The authors write, “Such spectra of high luminosities with prominent He II emission lines have never been observed from any stellar-mass black hole X-ray binaries, except for SS 433 and those having WNL donors [secondaries losing mass to the accretion disks of primaries in binary systems].” They exclude a number of stellar cases, including ULXs with WNL donors that exhibit stellar winds with the observed spectra. Wind terminal velocity is determined by surface gravity, making it difficult to explain the rapid variability of the He II line width in the recorded spectra. The authors conclude that SS 433 is intrinsically the same as ULXs, but is an extreme case with a particularly high mass accretion rate from its secondary, which accounts for the presence of its persistent jet outflows. © 2015 Phys.org Journal information: Nature Physics Explore further More information: “Supercritical accretion disks in ultraluminous X-ray sources and SS 433.” Nature Physics (2015) DOI: 10.1038/nphys3348AbstractThe black hole mass and accretion rate in ultraluminous X-ray sources (ULXs) in external galaxies, whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times1, 2, is an unsolved problem. Here we report that all ULXs ever spectroscopically observed have almost the same optical spectra, apparently of WNL type (late nitrogen Wolf–Rayet stars) or LBV (luminous blue variables) in their hot state, which are very scarce stellar objects. We show that the spectra do not originate from WNL/LBV-type donors but from very hot winds from the accretion disks with nearly normal hydrogen content, which have similar physical conditions to the stellar winds from these stars. The optical spectra are similar to that of SS 433, the only known supercritical accretor in our Galaxy3, although the ULX spectra indicate a higher wind temperature. Our results suggest that ULXs with X-ray luminosities of ~1040 erg s−1 must constitute a homogeneous class of objects, which most likely have supercritical accretion disks. Ultra-luminous X-ray sources in starburst galaxies (Phys.org)—Many black holes are believed to have surrounding accretion disks of matter trapped by gravity and spiraling toward the event horizon. Supercritical accretion disks (SCADs) are those with mass accretion rates exceeding the Eddington limit—this describes the maximum possible luminosity of an energetic body when the outward force of radiation is in equilibrium with gravitation. Masses that exceed the Eddington luminosity to produce SCADs emit extremely intense stellar winds from their outer layers. Citation: Researchers characterize mysterious ultraluminous X-ray sources (2015, June 9) retrieved 18 August 2019 from https://phys.org/news/2015-06-characterize-mysterious-ultraluminous-x-ray-sources.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.
Some birds lay eggs in the nests of other birds so that they will not have to raise them, this practice is known as parasitic egg laying, and works well enough for parasitic species to survive. But not all hosts welcome the parasitic eggs, some ignore them, or push them out of the nest. Also, some of the hatchlings are better guests than others, cuckoos for example, are known to push the other hatchlings out of the nest. In this new effort, the researchers sought to learn why it is some hosts are more tolerant than others.To find out, they looked at prior studies of parasitic bird practices—in all they found data on 198 different species, and took note of factors such as the environment in which the birds lived, the location, etc. and then drew up a phylogenetic tree. In studying their tree they were able to spot commonalities, such as that birds in northern latitudes were more likely to reject parasitic eggs. They also found that hosts tended to tolerate chicks that required a different diet than their own—such chicks would likely die anyway. Also, they found that eggs of parasitic chicks, such as cuckoos, that would hatch into birds larger than their own were often rejected—they same fate often befell eggs from birds that were a close relative. The researchers also noted that when some species such as cuckoos experienced high rejection rates from one species, they tended to move to another.In answer to the original question of why some birds tolerate parasitic eggs, the researchers suggest it is because sometimes it is almost impossible for host birds to tell the difference between eggs, and sometimes it is because the danger of harming their own young accidently is too great. They note that many species have constantly evolving egg coloring or design patterns to help prevent deception. Egg colours make cuckoos masters of disguise Explore further © 2015 Phys.org More information: The costs of avian brood parasitism explain variation in egg rejection behaviour in hosts , Biology Letters, DOI: 10.1098/rsbl.2015.0296 AbstractMany bird species can reject foreign eggs from their nests. This behaviour is thought to have evolved in response to brood parasites, birds that lay their eggs in the nest of other species. However, not all hosts of brood parasites evict parasitic eggs. In this study, we collate data from egg rejection experiments on 198 species, and perform comparative analyses to understand the conditions under which egg rejection evolves. We found evidence, we believe for the first time in a large-scale comparative analysis, that (i) non-current host species have rejection rates as high as current hosts, (ii) egg rejection is more likely to evolve when the parasite is relatively large compared with its host and (iii) egg rejection is more likely to evolve when the parasite chick evicts all the host eggs from the nest, such as in cuckoos. Our results suggest that the interactions between brood parasites and their hosts have driven the evolution of egg rejection and that variation in the costs inflicted by parasites is fundamental to explaining why only some host species evolve egg rejection. Common cuckoo. Image: Wikipedia. Journal information: Biology Letters (Phys.org)—A pair of researchers with Australia National University has conducted a study of parasitic egg laying with birds and as a result has found some hints on why it is that some hosts reject parasitic eggs while others do not. In their paper published in The Royal Society – Biology Letters, Iliana Medina and Naomi Langmore describe the study they conducted and what they learned as a result. Citation: Study offers hints on why some bird hosts reject parasitic eggs while others do not (2015, July 9) retrieved 18 August 2019 from https://phys.org/news/2015-07-hints-bird-hosts-parasitic-eggs.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.
A team of researchers from the University of Colorado in the U.S. and Université Paris-Saclay, in France has developed a new way to make biaxial nematic phase liquid crystals. In their paper published in the journal Science, the group describes the technique they developed and possible uses for the results. Philippe Poulin, with CNRS, University of Bordeaux offers a Perspective piece on the work done by the team in the same journal issue. Liquid crystals have become hugely important over the past half-century due to their use in phones, television sets and other screened devices. The type of crystals used in such devices are known as nematic phase liquid crystals, because their molecules line up in a certain way. They are also generally uniaxial, which means they line up in the same direction, but not necessarily in the same plane. But in recent years, scientists have begun to see that biaxial nematic phase crystals could offer additional benefits. Prior research has shown that because they would have fast switching speeds, they could serve an important role in the development of new electro-optical applications. Unfortunately, the development of such crystals has not met with much success. Some researchers have tried using board-like molecules while others have tried mixing rod-like molecules with disk-shaped molecules. Neither approach has produced the desired results. In this new effort, the researchers tried a new tactic—one that overcomes problems seen with the other methods.The new technique involves combining and mixing two types and sizes of nanorods—one organic the other inorganic. The inorganic nanorods were 1000 nanometers, while the organic nanorods were just two nanometers long on average. But there was more—the researchers had to tinker with the mixture to get the smaller rods to rest perpendicular to the larger rods, thus creating two planes. The researchers also found that the resultant biaxial nematic is not simply a superposition of the two nematics—the anisotropic properties between the two kinds of rods caused the smaller rods to be distributed in a way that resulted in biaxiality without the need for additional ingredients. This, the team notes, suggests the properties of the new liquid crystals are even richer than expected. More information: Haridas Mundoor et al. Hybrid molecular-colloidal liquid crystals, Science (2018). DOI: 10.1126/science.aap9359AbstractOrder and fluidity often coexist, with examples ranging from biological membranes to liquid crystals, but the symmetry of these soft-matter systems is typically higher than that of the constituent building blocks. We dispersed micrometer-long inorganic colloidal rods in a nematic liquid crystalline fluid of molecular rods. Both types of uniaxial building blocks, while freely diffusing, interact to form an orthorhombic nematic fluid, in which like-sized rods are roughly parallel to each other and the molecular ordering direction is orthogonal to that of colloidal rods. A coarse-grained model explains the experimental temperature-concentration phase diagram with one biaxial and two uniaxial nematic phases, as well as the orientational distributions of rods. Displaying properties of biaxial optical crystals, these hybrid molecular-colloidal fluids can be switched by electric and magnetic fields. How to make a biaxial nematic. Previous efforts to make biaxial nematics with either boardlike molecules or component mixtures have had limited success. Mundoor et al. used a different strategy to create a biaxial nematic by tuning the interactions between long inorganic nanorods and short organic molecules. Credit: V. ALTOUNIAN/SCIENCE Explore further © 2018 Phys.org Journal information: Science Citation: A new way to make biaxial nematic phase liquid crystals (2018, May 18) retrieved 18 August 2019 from https://phys.org/news/2018-05-biaxial-nematic-phase-liquid-crystals.html New type of liquid crystal identified; Holds promise of faster, lower priced liquid crystal displays 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.
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. © 2019 Science X Network Explore further A composite image of the Western hemisphere of the Earth. Credit: NASA Duarte noted that ever since the 1969 earthquake that struck off the coast of Portugal, he has been wondering how it happend—the area is not part of a subduction zone. It is quite the opposite, in fact. Duarte described is as like the plain of Kansas covered in water. It lies at the opposite end of the world from the so-called ring of fire, which hosts 90 percent of the world’s earthquakes. Notably, most of those quakes are due to tectonic plates pushing against one another. Over by the Iberian Peninsula, the opposite appears to be happening—the African and Eurasian plates are pulling apart as the former creeps east toward the Americas. Duarte noted that back in 2012, other researchers conducting seismic wave tests found what appeared to be a dense mass of unknown material beneath the epicenter of the 1969 quake. Some in the field suggested it could be the start of a subduction zone. Then, last year, another team conducted high-resolution imaging of the area and also found evidence of the mass, confirming that it truly existed. Other research has shown that the area just above the mass experiences routine tiny earthquakes.Duarte suggests the evidence to date indicates that the bottom of the plate is peeling away. This could happen, he explained, due to serpentinization in which water percolates through plate fractures and reacts with material beneath the surface, resulting in the formation of soft green minerals. The soft mineral layer, he suggests, is peeling away. And if that is the case, then it is likely the area is in the process of creating a subduction zone. He reports that he and his team members built models of their ideas and that they confirmed what he suspected. The earthquakes were the result of the process of birthing a new subduction zone. Citation: Geologists suggest Horseshoe Abyssal Plain may be start of a subduction zone (2019, May 8) retrieved 18 August 2019 from https://phys.org/news/2019-05-geologists-horseshoe-abyssal-plain-subduction.html More information: Delamination of oceanic lithosphere in SW Iberia: a key for subduction initiation? European Geosciences Union 2019. meetingorganizer.copernicus.or … 019/EGU2019-6001.pdf New ’embryonic’ subduction zone found A team of geologists led by João Duarte gave a presentation at this past month’s European Geosciences Union meeting that included a suggestion that the Horseshoe Abyssal Plain may represent the start of a new subduction zone. They presented evidence of possible peeling on the bottom of the tectonic plate that lies off the coast of Portugal.
The eastern state came visiting Delhi through Chalo Chalen Bengal (Let’s visit Bengal). The campaign aimed to project the tourism potential of West Bengal, attract more domestic and foreign tourists and facilitate better interaction with investors and industry stakeholders like travel operators.Chalo Chale Bengal witnessed a grand launch in the Capital with Krishnendu Nayaran Choudhury, Minister for Tourism, Government of West Bengal unvieling a new state-of-the-art tourism information centre at the WBICC (West Bengal Information and Cultural Centre). He also inaugrated Beautiful Bengal, a photography exhibition by Sanjay Das at the Muktadhara Art Gallery. Also Read – ‘Playing Jojo was emotionally exhausting’The day’s event proceeded along with a colourful ensemble of folk forms and cultural attractions of West Bengal, including Pat-er Gaan (songs about the rural tradition of story-telling with the help of scroll paintings), Baul Gaan (representing the unique spiritual musical heritage of Bengal) Purulia Chhau (tribal martial dance) and contemporary Bangla songs by Chandrabindoo.The next was an interactive session involving the Minister, senior officials of the Department of Tourism, Government of West Bengal and various stakeholders of the Indian tourism industry, including representatives of the Indian Association of Tour Operators (IATO) and Adventure tour Operators Association of India (ATOAI) which was followed by B2B meetings with potential tourism and hospitality sector investors, under the theme- Investment Opportunities.
When monsoon hits in, its prudent to take care of your swimming pools for your health.Though a proper circulation will ensure cleanliness by default, one may have to make just a bit of an extra effort to continue the delightful swimming experience during the monsoons. Vivek Mishra, MD of Premium Pools suggests some ways to go about it.When it rains, the pH levels of the water in the pool needs to be monitored all the more as the first rain at times is acidic, can play havoc in addition to getting dirty and contaminated water. It can get dangerous as well since harmful and toxic substances from the atmosphere may get mixed with the pool water. Also Read – ‘Playing Jojo was emotionally exhausting’So overall, the imbalance in the chemical composition of the pool water may rise. The rains will also bring along a lot of organic materials like pollen etc that gets accumulated in the pool. Within hours of the first shower of the monsoon, a significant variation in pool’s water quality can easily be noticed. For extreme weather conditions including monsoons, one can go for a pool enclosures or covers to eliminate any kind of water contamination. Also Read – Leslie doing new comedy special with NetflixA few more things can be done on an ad-hoc basis:Brushing the pool walls : this helps in eliminating the wild shrubs that might grow within the wall tiles. Also, this would help remove any fungal growth on the tiles surrounding the pool even deck area. Regular Chlorination : Adding chlorine tablets will help in preventing the growth of bacteria and even algae. Although the main cause of algae is stagnant water, routine chlorination would help prevent against health hazards like ear infections, athlete’s foot, skin rashes etc which become quite common with bacterial growth in water. Filtration : running the filters to clean the water on a daily basis is a good practice during rains. This way the debris and dirt can be completely cleared. Also, filtration helps in circulating the fresh water added to the pool as well. the said filter should also be regularly cleaned by the maintenance personnel.
Kolkata: In a unique move, the Calcutta Medical College and Hospital (CMCH) is planning to construct a children’s park with all the basic amenities outside the hematology department of the hospital so that children coming to the department with various blood related ailments can spend some quality time with his/her family members there.According to the senior official of the hospital, the construction of the children’s park will begin soon near gate number 1. The matter is already under process. The main purpose behind the idea is to ensure that children who come to the department with rare blood diseases can enjoy at the park. This will reduce the stress of the patients and help them overcome monotonous lives. Also Read – Heavy rain hits traffic, flightsA senior official of the hospital said there would be various amusement rides and games for children. A children’s swing will also be erected inside the park. It was learnt that the proposed children’s park would be situated close to the Hematology ward. This will also be developed as a part of the beautification work taken up inside the hospital campus.Patients suffering from Thalassemia and other blood related problems often visit the hospital for blood transfusion. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedMany others visit the outpatient departments of the hospital. Due to huge pressure of patients, children have to wait in queue for a long time which often becomes monotonous for them. Once the Park is constructed, those children can take a stroll in and around the park, spend some quality time with their parents enjoying the amusement rides which will be installed inside the park. The Park will be illuminated with various colourful lights. There will a big size water reservoir situated under the fountain. There are plans to set up a fountain inside the park as a part of the beautification drive at the hospital. Apart from developing a new one, some renovation works would be done at the existing park. In another significant move, the CMCH authorities have started the installation of an underground fire fighting system to check fire hazards at the hospital.A senior official of the hospital said: “The construction of the children’s park is expected to start later this year. The project will not only beautify the hospital campus but also be the reason of choice for the little children coming to the hospital from the far flung areas.”
Kolkata: Stressing the importance of cyber security, State IT Minister Bratya Basu on Wednesday said the compilators of various social media channels must be stricter to curb fake news.He was speaking at Cybercon 2018 and Technology Excellence Awards organised by the ASSOCHAM at a city hotel on Wednesday. Basu said the compilators of social networking sites must be on high alert to prevent such incidents.”We cannot take action against those who circulate fake news on social media. We can only identify them. It is the responsibility of the internal teams of various social networking sites to ban those who are involved in social crime from using their platforms. The nature of cyber crime is different from the others,” Also Read – Rain batters Kolkata, cripples normal lifeBasu maintained.Earlier on the day, State Additional Chief Secretary of IT department Debashis Sen said Blockchain technology, which the Bengal government has embraced, and the introduction of Fintech hub in New Town will bring a new dimension to the field of cyber security in the state. Nowadays, people are exposed to cyber threats. The onion server also poses a threat to people. Sen stressed on the need of Blockchain technology to check the cyber threats. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killed”If the introduction of Blockchain technology and fintech hub works out well, we will be able to tackle cyber crime. We have to pull our resources together and maintain cooperation between various fields like Telecom, E-commerce, emerging technology like Blockchain,” Sen said.Fintech hub is the brain child of Chief Minister Mamata Banerjee that will give a big boost to the IT department in fighting cyber threats. It is the Banerjee government that introduced Blockchain technology in the state. It may be mentioned that Blockchain provides secure public databases that are free from cyber attacks. There is a deep connection between Blockchain and Fintech, data sciences and cyber security and all of this are related to each other.Sen also sought co-operation from our neighbouring countries like Bangladesh, Nepal and others to fight cyber security issues as they go beyond boundaries. He also had a detailed discussion with Information and Communication Technology Minister of Bangladesh Zunaid Ahmed Palak on how both the countries can work together in this regard. Bengal has selected Blockchain as a technology for the future. The state IT department has tied up with the Centre for Development of Advanced Computing (C-Dac) and Maulana Abul Kalam Azad University of Technology to provide training and awareness about cyber security.A 24-hour online help-desk has also been thrown open by the department so that people can report any cyber security issues that they might have encountered.The state government is going to organise an international conference on how to check human trafficking in the digital arena. The event is scheduled to take place in December this year and state Women & Child Development and Social Welfare department will host the programme.
Kolkata: The Kolkata Municipal Corporation (KMC) has taken up a special drive to collect property tax arrears from defaulters.A civic team comprising senior officials of the Assessment department visited two premises on Topsia Road and put up distress warrant on the walls. KMC will take legal action against the owners if they fail to pay the arrears within the stipulated date. The drive has been initiated after the civic authorities failed to collect house tax arrears worth more than Rs 50 crore. There are around 7.60 lakh assesses living in the areas under the jurisdiction of KMC. Also Read – Rain batters Kolkata, cripples normal lifeThe civic officials visited 71, Topsia Road and 83/2/1, Topsia Road. The officials said that the two firms housed at 71, Topsia Road have not paid house tax dues worth Rs 71 lakh. The civic authorities said the owners have cleared 50% of the dues on Monday and gave an undertaking that the remaining amount will be paid by Friday. The owners of four firms housed at 83/2/1 Topsia Road have not paid house tax arrears worth several lakhs. The civic authorities have put up distress warrant and legal action will be taken against the owners if they fail to pay within the stipulated time. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedCivic officials said the defaulters have been requested to pay their dues several times but despite reminders, the officers refused to respond. They alleged that the defaulters wait for the waivers’ scheme and if it is implemented then the defaulters can square up the arrears by paying only the principal amount, while the penalty and interest amounts are waived. The officials said unlike in the past when property tax payers had to stand in long queues to pay tax, the system of online payment has been introduced now. Property owners can go to any e-counter and pay the tax and rebate is given if the tax is paid within the stipulated time.
The theatre fraternity came together on Friday night for a red-carpet awards gala at the 12th Mahindra Excellence in Theatre Awards (META) Festival. Curated by the Mahindra Group and Teamwork Arts, the week-long extravaganza came to an end as the best from the world of theatre were awarded the META at The Taj Mahal Hotel, Mansingh Road.The annual awards, which recognise excellence in theatre nationally, celebrate the intrinsic diversity and rich cultural traditions of India. The META is India’s most comprehensive award and a premier honour for the theatre fraternity, awarding on-stage and off-stage talent across 14 award categories, including the prestigious Lifetime Achievement Award. Also Read – Add new books to your shelfLike every year, this year’s short-list of META was diverse and showcased the best of Indian theatre. For a week, the festival staged 10 nominated plays that revolved around motifs ranging from mythology and caste to complex love stories and human emotions. The line-up featuring plays in English as well as several Indian Languages including Hindi, Bengali, Malayalam, etc., received an overwhelming response from the audience as the shows ran to packed houses. The Jury for META 2017 comprised theatre stalwarts Dolly Thakore, Mahesh Dattani, Sachin Khedekar, Seema Biswas, Avijit Dutt and Maya Krishna Rao. Also Read – Over 2 hours screen time daily will make your kids impulsiveWhile ‘Mahabharata’ bagged the award for Best Production along with Best Director and Best Choreography, ‘I Don’t Like It As You Like It’, won Best Ensemble, Best Stage Design and Best Actor in Supporting Role (Female), and ‘Elephant in the Room’ won Best Actor in a Lead Role (Female), Best Costume Design and Best Light Design, giving them three awards each. The award for Best Actor in a Lead Role (Male) was jointly presented to Anirban Bhattacharya (Awddyo Shesh Rajani) and Rajendra Panchal (Katha Sukavi Suryamall Ki). Noted theatre veteran, Arun Kakade was conferred the META Lifetime Achievement Award for his contribution to Indian theatre. He got a standing ovation as he received the Lifetime Achievement Award. He said, “I am so happy that META has been promoting Indian theatre for the last 12 years. There is diverse variety in the plays that come here. I have staged my plays here thrice before, but at the age of 86, I wasn’t expecting any award really. I am thankful to the META Festival organisers for this prestigious honour.”Hosted by Prateik Babbar and Shilpa Shukla, the scintillating awards night saw several luminaries, including Manoj Bajpayee, Sushma Seth, M.K Raina, Sachin Khedekar, Bubbles Sabharwal, Dadi Pudumjee, Vinod Nagpal, Sanjana Kapoor, Nicholas Idier and Jim Hollington. Performances by the band Samarpan, Harpreet, Neil Madhav and Rachna Yadav further enlivened the proceedings.Veterans from theatre, cinema, music, and dance presented the coveted awards to the ecstatic awardees and noted personalities like Manoj Bajpayee, Meera and Muzaffar Ali, Aditi Mangaldas and Seema Biswas were among those who gave away awards.Commenting on the awards, Jay Shah, Head, Cultural Outreach, Mahindra and Mahindra Ltd said, “The 12th META has concluded with all the drama, fanfare and applause it deserves. The 10 best productions from across India vied for the top honours in the nation’s capital. While awards were presented to just a few, each META participant has been a winner. The Mahindra Group too feels a great sense of victory for being able to establish a platform that defines excellence in Indian Theatre. A proud moment for us all!”
Applying for a new job? Just relax and be yourself during the interview, as a study has found that authenticity is key to securing an employment offer.Researchers, including those from University College London (UCL) in the UK, found that high-quality candidates who strive to present themselves accurately during the interview process significantly increase the likelihood of receiving a job offer.”People are often encouraged to only present the best aspects of themselves at interview so they appear more attractive to employers, but what we have found is that high-quality candidates – the top 10 per cent – fare much better when they present who they really are,” said SunYoung Lee from UCL School of Management. Also Read – Add new books to your shelf”Unfortunately, the same is not true for poorer quality candidates who can actually damage their chances of being offered the job by being more authentic,” said Lee.The research focused on the concept of ‘self- verification’, which refers to individuals’ drive to be known and understood by others according to their firmly held beliefs and feelings about themselves.To date, self-verifying behaviour was known to positively influence outcomes that unfold over time, such as the process of integration in a new organisation. Also Read – Over 2 hours screen time daily will make your kids impulsiveThe research shows, for the first time, that self-verification can have important effects in short-term interpersonal interactions as well, as in the hiring process.”In a job interview, we often try to present ourselves as perfect. Our study proves this instinct wrong,” said Celia Moore from Bocconi University in Italy.”Interviewers perceive an overly polished self-representation as inauthentic and potentially misrepresentative.”But ultimately, if you are a high-quality candidate, you can be yourself on the job market. You can be honest and authentic. And if you are, you will be more likely to get a job,” Moore said. The researchers conducted three studies – two field studies looking at the importance of self-verification for groups of professionals applying for different jobs and a third experimental study testing the mechanism behind the effects observed. In the two field studies, prior to job interviews, candidates reported their self-verification drive, and their quality was evaluated in face-to-face interviews. The candidates that had been evaluated as high quality had a 51 per cent likelihood of receiving a placement, but this increased to 73 per cent for those who also had a strong drive to self-verify.The second study replicated this effect in a radically different sample by assessing 333 lawyers applying for positions in a branch of the US military.For this group, high quality candidates increased their chances of receiving a job offer five-fold, from 3 per cent to 17 per cent, if they also had a strong drive to self-verify.This effect was only seen in high-quality candidates, and for those rated as low-quality, the drive to self-verify weakened their position.The third study was designed to test the mechanism behind this effect. For this, the researchers surveyed 300 people on their self-verification striving and selected those who were extremely high and extremely low in the distribution.The research was published in the Journal of Applied Psychology.
Have you ever wondered if that lemon twist on top of your martini or a dollop of cream on the ‘daal makhani’ is anything more than a quirk? Celebrity Chef Vikas Kumar delves deeper into the world of garnishes and shares his insights.CHERRY ON TOP So really, why are we discussing garnishes, I mean aren’t there more pertinent culinary topics that need more focus and attention? Sure there might be, but for the moment, let me tell you a story. Once when I was working for a certain organisation as a Galley Chef, I was asked if I’d want to be the ‘garnish man’. And I was like, sure! It’s just garnish, like a cherry on the cake, right? Wrong. So the job of the garnish man was to prepare all the garnishes of all the dishes across the sections – we are talking about some 3000 meals, almost 20 dishes, all intricately prepared and the garnish was, well,’the cherry on the cake’ and had to be just perfect since it was the first visual that the guest will get of the dish and will make up his own judgements before actually tasting (or not tasting) the dish. Apparently, the garnish man himself had to be the proverbial cherry just discussed, and in terms of skills and speed had to be second to none in the kitchen. Also Read – Add new books to your shelfSo let’s then discuss the ubiquitous crowning glory of the food dishes, the garnish. WHY GARNISH Why indeed? To put it anecdotally, well why do we wear jewellery/ make up? To look good, complete in a way perhaps. I’d say, same with food. If good food is the foundation of genuine happiness, the garnish on that food is what entices you towards it, makes you want it more and provides the visual stimulus to appreciate a food prior to sinking your teeth in. Garnishes are usually in colours opposite to the colour of the main dish, and to that extent provide a burst of colour and liveliness to the food dish. Imagine a plate of pasta in white sauce, white cheese and cream sitting in front of you. Now imagine it with a bright green sprig of parsley, some bright red cherry tomato and a splash of gorgeous light green olive oil. Imagine the difference. Get it? Also Read – Over 2 hours screen time daily will make your kids impulsiveThe second and a very important reason for food garnishing is that the garnishes always enhance the flavour of the main dish and complements it in the overall taste profile. Think about lemon with fish, birista (deep fried onion) on top of biryani, pistachio on Gajar Halva or a drizzle of balsamic vinegar on a salad, all these enhance the flavour of the main dish and make it taste better. Another reason for food garnishing is for the purpose of identification of the ingredients of the dishes. You will find, at most times the garnish tells more about the dish. For example, garnishing a pineapple pastry with pineapple and cherry, a dollop of cream on a cream soup, some makkhan on daal makkhani,…well you get the idea. Stop salivating! Filling up a plate or a serving dish is also quite functional of garnishes and many times garnishes are used to make the dishes look more full and complete. This is specially true for dishes that are served in a buffet or on a dinner table. A pertinent example will be a Christmas Turkey which has so many garnish components that it makes the dish look really fancy and celebratory, ditto for a salad or a dessert. Indian Food Garnishes Well from our childhoods we have seen all our food dishes integrated with their garnishes to an extent that we have always considered them to be a part of the dish itself. Think our dals without the garlic and cumin tempering, our Halvas without the tiny sprinkling of crushed cardamom seeds or a plate of chholey without the chopped dhania or the ginger juliennes. I have always maintained that Indian food is by far the most advanced, balanced and varied of all culinary styles of the world and has always been ahead of its times. Let me give you some examples of how the food garnishes have become integral to our food culture that we don’t really think much of them but they do indeed tick all boxes to be a worthy garnish and serves its full purpose. So there obviously are millions of Indian dishes that I could table here but will stick to the best known and easily relatable by all. First, the very popular Pao Bhaji – do you realize that a dollop of half melted butter, the chopped onions and coriander, tomato, lemon all are essentially garnishes and yet you will find at least all these in all pao bhajis served anywhere in the country or the world. In Bengal they serve ‘Masala Muri’ a more pungent and humble cousin of the bhelpuri and you will almost always find it garnished with some peanuts, a slice of coconut and some sprouts, nobody really thinks much but classic garnishes look good, taste good and provide an interesting contrast to the main food item. Similarly, almost all Indian food items have inherent garnishing that gives the food complexity, texture and colour. The case in point is the huge Indian Thalis that are served with a multitude of dishes in small bowls or saucers, yet all these will almost always have their individual garnishes, often different from each other. RECIPE So I have been scratching my head as to which recipe to give that will do justice to a topic such as this. Obviously, I had to find a recipe where the garnish is highlighted and stands out. To that extent, I am giving the recipe for a French dish. In French cuisine, there are many dishes that are known by their garnishes and are distinguishable only based on that. The name of the dish is ‘French Onion Soup’ and is always served with a rather discernible garnish which is a large bread and cheese crouton. FRENCH ONION SOUPIngredients 100 g Butter 30 ml Olive oil 450 g Sliced onions 500ml Chicken/Beef /Vegetable stock 30 ml Red wine (optional) 1 g Dried thyme Salt and pepper to taste For the toast 2 slices French bread 2 slices cheddar cheese 20 g Grated Parmesan cheese Method Melt butter with olive oil in a stock pot on medium heat. Add onions, and cook on a medium flame until tender and translucent. Do not brown the onions. Add the stock, wine and thyme. Season with salt and pepper, and simmer for 30 minutes. Layer each slice of bread with a slice of cheese, and 1 tablespoon Parmesan cheese. Ladle the soup in warm bowls. Just before serving, place the toast on the soup and put under a hot salamander/grill until the cheese melts and bread turns toasty. Serve immediately.
During a time when Americans would stand in line for hours just to get a loaf of bread, one of the most massive construction projects in history was underway in the Black Canyon of the Colorado River. The great Hoover Dam stands as tall as a 60 story building. Its base is as thick as two football fields. Its construction employed enough concrete to pave a stretch of road long enough to span the continental United States — from San Francisco to New York City.In spite of only taking five years to build, it’s taller and all the Seven Wonders of the ancient world, including the Pyramid of Giza and strong enough to hold back all the water pouring over Niagara Falls.Hoover DamA worker stands by the 30 ft (9.1 m) diameter Nevada penstock before its junction with another penstock that delivers water to a turbine. Photo by Jeffrey G. Katz CC BY 3.0Apache employed as high-scalers on the construction of Hoover Dam.Concrete sluices from a bucket to a form at Hoover Dam, workers prepare to flatten out the pour.Drillers on the construction of Hoover Dam.First water to pass through diversion tunnels flowing from outlet portal of Diversion Tunnel.Hoover Dam, 1934. Photo by Bureau of Reclamation CC BY-SA 2.0Hoover Dam, Boulder City, Nevada.The behemoth building project started in 1931 — a whopping 29 years after engineer Arthur Powell Davis had the vision to build it. His goal was to keep downstream farming communities from being devastated by the floods coming out of the Colorado River.But the Hoover Dam would also provide a dependable supply of irrigation water to the surrounding areas, even as far as Los Angeles and Southern California.When the plans for the dam were finally drawn up in 1922, professional engineers deemed the building project “impossible.” Nevertheless, once underway, the project employed scores of Las Vegas men who were desperately out of work as a result of the Great Depression.Some of these men rode in from out of state with their families and waited for a year to have the opportunity to work on the project.This exploded the population of Las Vegas from 5,000 to around 15,000 by the time the project started.Hoover Dam, Boulder City,Looking down at high scalers above the Colorado River.Looking downstream through Diversion Tunnel No. 2.Native Americans employed on the construction of Hoover Dam as high-scalers.Operations at downstream end of foundation excavation.Operations at inlet portal of diversion tunnel No. 2. Invert concrete and trashrack transition base are seen.Pouring side wall concrete in diversion tunnel No. 4.Pressure grouting jumbo in operation in Diversion Tunnel No. 4.Side-wall concrete in place in diversion tunnel No. 2.Sidewall tunnel forms being utilized in forming bulkhead gate structure at inlet portal of Diversion Tunnel No. 1.Stripping operations at Arizona gravel deposit.Tamping concrete behind forms in placing side-wall concrete in diversion tunnel lining.The construction of Hoover Dam, Boulder City, Nevada.This piece of equipment, named a Jumbo Rig, was designed to speed up the Hoover Dam’s tunnel drilling process. Built on the back of a 10-ton truck, 24 to 30 drills could be operated at once.Trench at upstream toe of Boulder Dam foundation, looking toward Nevada side from top.Trimming jumbo being lowered into inclined spillway tunnel on Nevada side.On May 12, 1933, demolition crews detonated four tons of dynamite to prepare the canyon for early construction.The project was so strenuous and dangerous, approximately 112 men died during its construction. Some died by drowning, others by falling and a few men even committed suicide on the job site.The dam got its name when Ray L. Wilbur (Secretary of the Interior) named it after President Herbert Hoover at the spike driving ceremony for a nearby railroad project. President Franklin D. Roosevelt dedicated the Hoover Dam on September 30, 1935.Read another story from us: George Washington’s Bizarre False TeethThough the name had been changed to “Boulder Dam,” in 1933 by Harold Ickes, it regained its original name 14 years later. Today, the Hoover Dam stands as one of the wonders of the modern world and supplies power to nearly one-and-a-half million Americans every year.