Professor Gwo-Bin Vincent Lee, from National Cheng Kung University, Taiwan, and his colleagues have manufactured three-dimensional, micromachined magnetic tweezers to manipulate DNA molecules. Their method was published in the February 7, 2006 issue of Nanotechnology. Citation: New 3D Magnetic Tweezers (2006, March 27) retrieved 18 August 2019 from https://phys.org/news/2006-03-3d-magnetic-tweezers.html Lee’s team immobilized the modified magnetic bead on a gold pattern using a current of 500mA and a ring trapper. “The ring trapper collects a tethered-magnetic bead DNA molecule to a specific area.” The scientists bound the other end of DNA to a streptavidin, unmodified magnetic bead. “This extremity is manipulated under a magnetic field generated by micro-electromagnets,” Lee said.Lee and his team put the bead on the center of the magnetic tweezers so that the DNA had equal magnetic force throughout its contour length. The team conducted experiments with current from the microelectromagnets. They found that, at 453 pN, DNA is highly elastic.”DNA is a negatively-charged polyelectrolyte– at high ionic strength, the majority of negative charges neutralize along the DNA backbone, causing DNA to be more susceptible to elastic elongation,” Lee said. When the scientists applied a current of 400mA to the single DNA molecule, it stretched to a length of 14.74um. In contrast, the team attached two magnetic beads to two DNA molecules, at the same time, and applied 400mA of current. The two DNA molecules stretched to 6.5um.Why there a difference in stretching between the single and double DNA molecules? “The extension of two parallel DNA molecules is much lower than that of a single DNA molecule, which causes a higher spring constant,” Lee explained. The scientists theorized that the extension may be lower because of curling, different attachment points, or nicking.The scientists also experimented using a 2.8um magnetic bead and a 1.0um magnetic bead, with the same magnetic field gradient. “Because the bigger magnetic bead has a higher magnetic moment, it can induce a larger magnetic force,” Lee said. The scientists have proven the efficiency of the magnetic tweezers. “This method doesn’t lose sensitivity and functionality, unlike the use of large-scale and optical tweezers. Moreover, the small size of the magnetic tweezers allows them to be mass-produced at low cost,” Lee said.By Syeda Hamdani, Copyright 2006 PhysOrg.com New system would use rotating magnetic field to detect pathogens “This study could provide a provide a powerful tool for exploring the bio-physical properties of biomolecules, bio-polymers and cells,” Lee said.Lee’s team made magnetic tweezers from six, hexagonal micro-electromagnets. The scientists wrapped three-dimensional coils, with a width of 80 um, spacing of 100 um, and thickness of 25 um, 30 times around a permalloy core. They chose permalloy because it magnetizes and demagnetizes with low-magnetic field strength.The type of DNA was likewise important to the study’s success. The team used λ-phage DNA, which had two complementary 12-base, single-stranded 5′ overhangs. “These overhangs allow phage DNA to easily be derivatized with various functional groups by base-pairing with a complementary sequence,” Lee explained. Each base pair of DNA was 0.34nm, without any external force.The scientists colored the DNA with a green dye, keeping the base pair to dye molecule ratio at 5 to 1, in order to have a high signal-to-noise ratio. “Since a DNA molecule only has a 2nm thickness, we can’t observe it with a normal optical microscope,” Lee said. The dye allowed the team to view DNA under a fluorescent microscope.An important element to Lee’s study was a microfluidic channel integrated with the magnetic tweezers. This channel had a width of 5mm, height of 60um, and length of 2cm. “We sealed the microfluidic channel with a glass cover slip (100um thick), using double-sided sticky tape (60um thick).””The microfluidic channel allowed us to observe a single DNA molecule in real-time,” Lee stressed. “We introduced the DNA by pressuring it with a syringe pump into the channel.”Another element to the study was what to use on DNA extremities. “A DNA specific-end anchoring must meet several rigorous requirements, including specific binding, binding strength, localized binding, and complexity level of the procedure,” Lee said. Both thiol group-gold and streptavidin-biotin met all these requirements. “They provide a highly efficient, strong, and specific anchoring,” Lee said.The scientists first bound both ends of DNA to biotin molecules. Next, the team bound one end of DNA to a streptavidin-coated, thiol-modified magnetic bead. “If we label one DNA-end with a thiol group, it must be bound to a gold, magnetic particle. But the gold, magnetic particle was not commercially available,” Lee explained. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further
Citation: Using Superheroes to Teach Physics: College Courses in Sci-Fi (2009, March 31) retrieved 18 August 2019 from https://phys.org/news/2009-03-superheroes-physics-college-courses-sci-fi.html Perhaps the most scientific of these classes is The Science of Superheroes, a course taught at the University of California at Irvine. Superman becomes the poster-boy for fluid dynamics as he soars through the air. I’d imagine that students could learn about the drag produced by Superman’s cape. Oh, and calculate how fast Lois Lane is plummeting toward the earth. How fast will Superman need to fly in order to catch her before she splatters on the pavement? Also addressed in the class: The strength of spider silk. You know that Peter Parker wants in on this one. WonderWoman and other superheroes are also used to illustrate basic physics concepts. If elementary and secondary school teachers used Superman and Batman to teach science, I wonder if there would be more early interest in science.At Frostburg State University there is a class offered on The Science of Harry Potter. I guess it’s more fantasy than science fiction, but deep scientific questions are probed in this course. Remember the three-headed dog? Perhaps genetic engineering can explain it. And flying broomsticks (and falling off of them) offer yet another opportunity to talk about the physics of flight and gravity.Science fiction offers more opportunities than just studying science. Just as science has long provided a basis for some philosophical and ethical discussions, science fiction provides those opportunities. Philosophy and Star Trek, taught at Georgetown University, explores the deep issues presented in Star Trek, such as whether or not an android like Data constitutes a person. Race and metaphysics are also tackled. And topics encompassing the nature of reality and time travel are also discussed.Sure, science majors aren’t going to take these classes. But they could go some distance in helping everyone else learn a little more about science — and even persuade a few more to become interested in following a scientific path.© 2009 PhysOrg.com Explore further Astrophysicist also science fiction writer (PhysOrg.com) — One of the more perplexing questions facing science these days is this one: How do we get more young people interested in science? Leading the way are a number of college courses — that can be taken for credit — that focus on the science in science fiction. After all, why can’t superheroes, Star Trek and Harry Potter teach us about the answer to life, the universe and everything? (Or, at least debate the merits of the answer “42”.) Can Superman teach college students about fluid dynamics? 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. More information: Motivating voter turnout by invoking the self, PNAS, Published online before print July 18, 2011, doi:10.1073/pnas.1103343108AbstractThree randomized experiments found that subtle linguistic cues have the power to increase voting and related behavior. The phrasing of survey items was varied to frame voting either as the enactment of a personal identity (e.g., “being a voter”) or as simply a behavior (e.g., “voting”). As predicted, the personal-identity phrasing significantly increased interest in registering to vote (experiment 1) and, in two statewide elections in the United States, voter turnout as assessed by official state records (experiments 2 and 3). These results provide evidence that people are continually managing their self-concepts, seeking to assume or affirm valued personal identities. The results further demonstrate how this process can be channeled to motivate important socially relevant behavior. Explore further How social pressure increases voter turnout: Evidence from a large-scale field experiment (PhysOrg.com) — A new study by social psychologist Christopher Bryan and his colleagues at Stanford University shows just how easily people can be manipulated using their own vanity; by doing nothing more than changing the word “vote,” to “voter,” on a survey, Bryan et al, have demonstrated that it’s possible to increase voter turnout in real-world elections. The team has published their results in the Proceedings of the National Academy of Sciences. © 2010 PhysOrg.com To see if his hunch, that people would respond better to the opportunity to be called a voter, rather than simply asking them to vote, could improve voter turnout, Bryan and his team first sent out surveys to just 38 people prior to the 2008 presidential election. Half the group got a survey asking if it was important to vote, the other half got surveys asking if it was important to be a voter. 87.5 responded yes to the second question while only 55.6 did so with the first.Feeling he was on to something, Bryan then set his sights higher, for his next experiment, he and his team sent surveys to 133 registered voters in California one day before the 2008 election. Afterwards, using voting records, he was able to ascertain that 82% of those who got the “vote” question actually voted, while 96% of the “voter” group did.Then to make sure his results weren’t tainted by the fact that the recipients of the surveys were all quite young, and Californian, the team sent out surveys to 214 older registered voters from New Jersey just before their gubernatorial election, and found similar results; 90% for the “voter” group versus 79% for the “vote” group. Bryan says this is the largest ever measured effect on voter turnout.Bryan suspects that the increase is due to how people view themselves, or maybe just how they want to; by wording a survey that allows a person to see themselves as a voter, vanity is struck because most people view being considered a voter, a positive thing; just asking people to vote on the other hand, sounds more like you’re asking them to do something, which in voter surveys doesn’t seem to stoke much of anything, except perhaps excuses in some people. That the survey was able to translate words into action appears to be due to the opportunity it affords the recipients to be being considered something so positive as a voter, a distinction they perhaps hadn’t quite fully considered prior to receiving the simple survey.To see if the same sort of results can be had in other areas, Bryan and his team will next be looking at whether such word phrasing changes can be effective in helping people diet, or to work to save the environment, etc. Citation: Study shows voter turnout can be increased with simple word change (2011, July 19) retrieved 18 August 2019 from https://phys.org/news/2011-07-voter-turnout-simple-word.html
While the atomic clock is based on vibrations of electrons orbiting an atom, the nuclear clock would instead be based on tuning the spatial orientation of electrons that cause the nucleus of an atom to jump back and forth between high and low energy states using a very specific frequency of light. The result, the researchers say, would be a clock tuned by a laser that would drift only about one second in 200 billion years, or 14 times the believed age of the universe and 60 times more accurate than current atomic clocks. The only trick here apparently, is in figuring out just what that frequency would be.For most people, the accuracy of a clock isn’t really all that much of a big deal. For this reason something called Coordinated Universal Time (UTC) is used for ordinary living. It’s derived from atomic clock measurements but also uses leap seconds based on the rotation of the earth to help keep everyone straight. For other applications though, more accuracy is needed. GPS is one such example. Because there are four satellites used for GPS tracking, some means of timing their signals must be used to coordinate data sent from them and relayed to Earth based navigation systems. The smaller the errors in timing, the more accurate the systems become.The main reason the nuclear clock would be so much more accurate than the atomic clock is due to the fact that atomic clocks are susceptible to ambient magnetic and electric fields that can throw off the vibrations of the electrons a tiny bit. Using a laser to precisely control the nucleus bouncing between states however would not be nearly as susceptible to such interference. More information: A Single-Ion Nuclear Clock for Metrology at the 19th Decimal Place, arXiv:1110.2490v1 [physics.atom-ph] arxiv.org/abs/1110.2490AbstractThe 7.6(5) eV nuclear magnetic-dipole transition in a single 229Th3+ ion may provide the foundation for an optical clock of superb accuracy. A virtual clock transition composed of stretched states within the 5F5/2 electronic ground level of both nuclear ground and isomeric manifolds is proposed. It is shown to offer unprecedented systematic shift suppression, allowing for clock performance with a total fractional inaccuracy approaching 1 x 10^-19.via Newscientist Partial energy-level diagram of the 5F5/2 electronic ground levels within the nuclear ground and isomer manifold of 229Th3+. See arXiv:1110.2490v1 paper for details. Credit: arXiv:1110.2490v1 (PhysOrg.com) — For almost sixty years, the world has considered the atomic clock the gold standard for keeping time. Its accuracy is such that it drifts by only about four seconds over a period of about thirteen and a half billion years (about the time since the Big Bag is thought to have occurred). Now it appears a new more accurate way to measure time might be on the horizon. Corey Campbell at the Georgia Institute of Technology and five of his colleagues have teamed together to describe in their paper pre-published on arXiv, how a more accurate nuclear clock might be devised. Explore further Portable Precision: A New Type of Atomic Clock © 2011 PhysOrg.com Citation: Research team shows nuclear clock could be 60 times more accurate than atomic clock (2011, November 9) retrieved 18 August 2019 from https://phys.org/news/2011-11-team-nuclear-clock-accurate-atomic.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.
ICC’s chief executive officer Dave Richardson on Sunday said the game’s governing body is all set to prune the number of teams from 14 to 10 for the next Cricket World Cup, scheduled to be held in England in 2019.There is a possibility that the ICC World T20 will be made a 16-team event which would encourage some of the lower rung teams to get a taste of competitive cricket. The members of the ICC Executive Board will be meeting here on Monday for a “Strategic Review Meeting” in which the members are likely to agree to a 10-team format rather than existing 14 team structure, which makes it a cumbersome seven-week long tournament with a number of inconsequential matches. Also Read – Khel Ratna for Deepa and Bajrang, Arjuna for Jadeja“The way we are going, I believe we need to consolidate things to ensure that there is more competition amongst teams at the highest level. If we get a 10-team World Cup, all 10 teams must be capable of winning the tournament,” Richardson told PTI during an exclusive interview. “Like in 1992, we had a nine-team format, where everyone played each other. It was by far the most exciting World Cup where it was difficult to predict the four semi-finalists. So we are hopeful that 10-team format might work,” the former South Africa wicketkeeper sounded positive about the downsizing of teams. Also Read – Endeavour is to facilitate smooth transition: ShastriRichardson said ICC’s main aim would be to have a “more targeted approach where the countries doing well should be rewarded adequately”. “If we have Test cricket, our aim is to make sure that all our 10 Full Members are capable of beating each other. Similarly, the ICC thinks that World T20 must be a tournament featuring something in the range of 16 countries. We want a targetted approach in order to create more competitive teams at the higher level. Teams like Ireland and Afghanistan need to be rewarded,” he said.
Is survival on earth becoming even more precarious than in space? Can our cities survive for long if they continue to grow irresponsibly? How can policy makers intervene to make our cities self-sufficient? Many more such pertinent questions are being raised through The Undivided Mind, an exhibition emanating from a two-week residency that explores the crossover between two seemingly unrelated fields of Art and Science. The works created during this residency by the CAAS Collective (a trio of Susmita Mohanty, Barbara Imhof and Sue Fairburn) and Rohini Devasher will be open for public viewing at Khoj Studios on February 27. Also Read – ‘Playing Jojo was emotionally exhausting’The aim of the exhibition – which will comprise of posters, collages, photographs, info-graphics and videos – is to draw a parallel between the earth we inhabit and outer space, bringing into focus questions about environment degradation, sustainability, recycling and efficient use of limited natural resources. Hence, this exhibition explores the ways in which scientific processes and discovery can be coupled with visual art production and vice-versa. CAAS, in fact, aims to convert Khoj Studios, the venue of the exhibition, into a mini space-station as part of its project. Also Read – Leslie doing new comedy special with NetflixSusmita Mohanty says “The space stations are super-efficient and self-sufficient for the astronauts to sustain. A city like Delhi sources almost everything from electricity to water from elsewhere. CAAS is a thought which believes that every city should be self sufficient like a space station. We need smart cities in the future if we have to survive. We want people to conceptualise, visualise and materialise how to tread the planet lightly.” CAAS Collective or the ‘City As A Spaceship’ collective comprises of Susmita Mohanty (spaceship designer and aerospace entrepreneur), Barbara Imhof (space architect) and Sue Fairburn (scientist and design researcher). Rohini Devasher is an emerging visual artist who has participated in several past residency programs at Khoj. The works on display at Khoj will focus on data collected through CAAS’s interactions with people of Khirkee and the neighborhood. Sue Fairburn noted, “Through our collages that juxtapose various living environments on Earth and that in space, we want to create a dialogue that earth and space are not exclusive of each other.”Barbara Imhoif, a space architect stated, “Living in space is not just about science, it’s also about a harmony in cultural diversity, human emotions, feelings of isolation and dependence. Comparing this to our life in cities, a CAAS City can be an inspiration, an alternate view, for a future city and a way to project and achieve our dreams and visions of an equitable and environment-friendly urban life.”Rohini Devasher is a Delhi based artist whose art practice is rooted in science and whose recent work has involved research and fieldwork in amateur astronomy where myth and fiction blur the boundaries of what is real and imagined. She said, “For the show, I hope to continue this imagination of new analytical and fictitious spaces with the projection of the strange, and the poetic into the scientific. I am interested in investigations of natural systems using modes of ‘field work’ and ‘expedition’. I have found these to be particularly useful in the observation and understanding of the relationship between humans, their environment and how this is constructed.”
Kolkata: Land has been allotted at Rajarhat for setting up two police stations of the Bidhannagar Police Commissionerate.According to the sources in the state secretariat, the state Home department has sent a proposal to sanction and release a total amount of Rs 23.27 crore for payment of lease premium to West Bengal Housing Infrastructure Development Corporation (HIDCO), for allotment of the plots to set up the police stations.The plots have been allotted in Action Area II E and Action Area III E to the Home and Hills Affairs department, on a 99 year leasehold. The plot in Action Area II E measures around 0.601 acres while the one in Action Area III E is of 0.661 acres. Also Read – Heavy rain hits traffic, flightsIt may be recalled that the transfer of land has taken place on the basis of the approval of the Standing Committee of the Cabinet on Industry, Infrastructure and Employment of West Bengal. The meeting of the Standing Committee was held in this connection on January 18.It may be mentioned that the Mamata Banerjee government had set up Howrah, Bidhannagar, Barrackpore, Siliguri and Asansol-Durgapur Police commissionerates soon after coming to power, to ensure better policing. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedShe has also stressed on the development of infrastructure of all the police commissionerates. Similarly, as a measure to bring into place better infrastructure for Bidhannagar Police Commissionerate, the land has been allotted where the two police stations will be constructed.It may be mentioned that earlier, 5.91 acres had been taken from HIDCO to develop infrastructure, including setting up of a parade ground, police station, office and barrack, town police outpost and police line in New Town. The land was taken from HIDCO at a lease amount of Rs 24.77 crore.With setting up of the police commissionerates, the rate of crime has gone down and at the same time, the law and orders issues are also controlled in a better way. Apart from the commissionerate areas, steps were also taken up to ensure better policing in the non-commissionerate areas.Steps taken by the police and development of infrastructure have also helped curb the rate of accidents in the state.
Kolkata: Tension gripped the locals of Kidderpore after a 3-year-old child was crushed under the wheels of a speeding truck.The incident took place at Kidderpore on Sunday night. An irate mob ransacked the truck and set it on fire after the incident.The locals staged a demonstration at the accident site, protesting against the rash driving of vehicles.A huge contingent of police rushed to the spot to bring the situation under control.The irate mob engaged in a verbal altercation with the policemen. Some of the senior police officers also rushed to the spot and tried to pacify the mob. The agitation was later lifted after senior police officers assured Also Read – Heavy rain hits traffic, flightsthem that they would crack down on vehicles that flout traffic norms. Police said Santosh Sahu, a resident of Port area was returninghome along with his wife Bharati and 3-year-old son Ayan on his motorcycle.While crossing the DC port office, the victim suddenly fell from the bike.As a result, a truck, which was coming from behind, run over the victim. He died on the spot.The incident infuriated the locals and they went on rampage.The truck driver and the helper managed to flee the spot immediately after the accident. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedThe eyewitnesses told police that the truck was running at a high speed as a result of which the driver could not control the vehicle.According to the investigation, police said the child fell from bike when his father applied a sudden brake as there was a pothole on the road.The body was sent to SSKM Hospital by the police for postmortem.The locals have alleged that heavy duty trucks ply through the area at a high a speed resulting in accident.The matter was raised with the local police administration but no steps have been taken so far in this regard to check the speed of the vehicles.Police have started a detailed probe in this regard. Raids are being conducted at various places to nab the truck driver who has been absconding since the incident took place. Police have seized the vehicle.