research (39)

2020 Nano Highlights...

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Image source: The article link, but it should symbolize how last year felt to the sane among us.

Topics: Biology, Materials Science, Nanotechnology, Research

Snake vision inspires pyroelectric material design

Bioinspiration and biomimicry involve studying how living organisms do something and using that insight to develop new technologies. Pit vipers have two special organs on their heads called loreal pits that allow them to “see” the infrared radiation given off by their warm-blooded prey. Now, Pradeep Sharma and colleagues have worked out that the snakes use cells that act as a soft pyroelectric material to convert infrared radiation into electrical signals that can be processed by their nervous systems. As well as potentially solving a longstanding puzzle in snake biology, the work could also aid the development of thermoelectric transducers based on soft, flexible structures rather than stiff crystals.

Nanotechnology and materials highlights of 2020, Hamish Johnston, Physics World

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Planes, Trains, and Automobiles...

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Topics: Biology, COVID-19, Research

With COVID-19 reaching the most dangerous levels the U.S. has seen since the pandemic began, the country faces a problematic holiday season. Despite the risk, many people are likely to travel using various forms of transportation that will inevitably put them in relatively close contact with others. Many transit companies have established frequent cleaning routines, but evidence suggests that airborne transmission of the novel coronavirus poses a greater danger than surfaces. The virus is thought to be spread primarily by small droplets, called aerosols, that hang in the air and larger droplets that fall to the ground within six feet or so. Although no mode of public transportation is completely safe, there are some concrete ways to reduce risk, whether on an airplane, train or bus—or even in a shared car.

At a casual glance, air travel might seem like the perfect recipe for COVID transmission: it packs dozens of people into a confined space, often for hours at a time. But many planes have excellent high-efficiency particulate air (HEPA) filters that capture more than 99 percent of particles in the air, including microbes as SARS-CoV-2, the coronavirus that causes COVID. When their recirculation systems are operating, most commercial passenger jets bring in outside air in a top-to-bottom direction about 20 to 30 times per hour. This results in a 50–50 mix of outside and recirculated air and reduces the potential for the airborne spread of a respiratory virus. Many airlines now require passengers to wear a mask during flights except for mealtimes, and some are blocking off middle seats to allow more distancing between people. Companies have also implemented rigorous cleaning procedures between flights. So how does this translate into overall risk?

“An airplane cabin is probably one of the most secure conditions you can be in,” says Sebastian Hoehl of the Institute for Medical Virology at Goethe University Frankfurt in Germany, who has co-authored two papers on COVID-19 transmission on specific flights, which were published in JAMA Network Open and the New England Journal of Medicine, respectfully. Still, a handful of case studies have found that limited transmission can take place on board. One such investigation of a 10-hour journey from London to Hanoi starting on March 1 found that 15 people were likely infected with COVID-19 in-flight—and that 12 of them had sat within a couple of rows of a single symptomatic passenger in business class. (The results were published this month in the U.S. Centers for Disease Control and Prevention’s journal Emerging Infectious Diseases.) Most of these flights occurred early on in the pandemic, however, and in the case of the March 1 flight, masks were likely not worn, the researchers wrote. Meanwhile, a recent Department of Defense study modeled the risk of in-flight infection using mannequins exhaling simulated virus particles and found that a person would have to be exposed to an infectious passenger for at least 54 hours to get an infectious dose. This finding assumes the infected passenger is wearing a surgical mask, however, and it does not account for the dangers involved in removing the mask for meals or talking or in moving about on the plane.

Evaluating COVID Risk on Planes, Trains, and Automobiles, Sophie Bushwick, Tanya Lewis, Amanda Montañez, Scientific American

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Argonne, and STEM...

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Students and instructors wave bye to each other after the close of a virtual session of All About Energy. (Image by Argonne National Laboratory.)

Topics: Education, Energy, Research, STEM

Argonne Educational Programs and Outreach transitioned to virtual summer programming, ensuring that Argonne continues to build the next generation of STEM leaders.

At the U.S. Department of Energy’s (DOE) Argonne National Laboratory, scientists and educators have found new ways to balance their work with safety needs as the laboratory’s Educational Programs and Outreach Department successfully transitioned all of its summer programming to a virtual learning environment.

By connecting scientific and research divisions across the laboratory, Argonne was able to create multiple virtual programs, helping young people stay connected and engage with the laboratory’s science, technology, engineering and math (STEM) education opportunities.

“Providing STEM opportunities and a constant presence with our next generation of STEM professions during a time that is unsettling and turbulent for everyone, but especially our school age and university student populations, was our top priority.” — Meridith Bruozas, Educational Programs, and Outreach manager

“Argonne continues to adapt and lead impactful science during the ongoing pandemic, a strategy that includes strengthening the STEM pipeline with unique educational programs for future scientists and engineers,” said Argonne Director Paul Kearns. ​“For years, hundreds of students have pursued summer learning opportunities at Argonne that are not available anywhere else. I’m pleased that in 2020 our lab community came together to maintain these high-quality STEM experiences through a successful virtual program for next-generation researchers.”

Argonne provides STEM opportunities for more than 800 students during pandemic, Nathan Schmidt, Argonne National Laboratory

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Communication...

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Topics: Biology, COVID-19, Politics, Research

Living through a pandemic has resulted in phrases like RT-PCR, immune response, and aerosolized droplets becoming part of the regular vocabulary for a portion of the population. It has also underscored the important role that we all have to play as scientists in communicating science to the public. As research related to COVID-19 has moved forward at unprecedented rates, misinformation has also multiplied and spread at a terrifying pace. And no matter where you stand politically, all of this happening in an election year for the US further underscores the ways in which science has become an increasingly partisan issue.

Did I mention that the holidays are also approaching? While gatherings of family and friends may look different this year, you may still be anticipating a challenging conversation over a holiday meal with someone who has different viewpoints from yours.

Our situation comes with innumerable challenges. However, it also provides an opportunity for scientists to make a powerful contribution to society and demonstrate the value of science education. Whether or not you are engaging in research directly related to COVID-19, you can help those around you separate facts from myths, interpret the data that are available, and make better-informed decisions.

This realization occurred to me this spring. As positive cases of COVID-19 were just starting to appear in the US, I found myself talking to my physical therapist about the virus and potential treatments. Although I don’t work in drug development, I understand enough of the chemistry to know how nucleoside analogs such as the drug remdesivir function. I excitedly explained how viruses are sloppier than normal human cells when replicating their genomes and how researchers can capitalize on this to make drugs. A few days later, I found myself having a similar conversation with my mom. I wasn’t in a place to predict the efficacy of any drug, but I could at least explain why antivirals like remdesivir had a shot at working, while hydroxychloroquine was less promising. After these two conversations, it struck me that I could also share this knowledge with a broader population on social media.

Science communication is a skill that takes practice to develop, and I am still learning and growing. The stakes couldn’t be higher, but the important part is that any scientist can build this capability to communicate effectively.

We’re all science communicators. Here’s how to do it better, Jen Heemstra, Chemical & Engineering News

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Black Phosphorus...

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The black phosphorus composite material connected by carbon-phosphorus covalent bonds has a more stable structure and a higher lithium-ion storage capacity. Credit: DONG Yihan, SHI Qianhui, and LIANG Yan

Topics: Alternative Energy, Applied Physics, Battery, Nanotechnology, Research

A new electrode material could make it possible to construct lithium-ion batteries with a high charging rate and storage capacity. If scaled up, the anode material developed by researchers at the University of Science and Technology of China (USTC) and colleagues in the US might be used to manufacture batteries with an energy density of more than 350 watt-hours per kilogram – enough for a typical electric vehicle (EV) to travel 600 miles on a single charge.

Lithium ions are the workhorse in many common battery applications, including electric vehicles. During operation, these ions move back and forth between the anode and cathode through an electrolyte as part of the battery’s charge-discharge cycle. A battery’s performance thus depends largely on the materials used in the electrodes and electrolyte, which need to be able to store and transfer many lithium ions in a short period – all while remaining electrochemically stable – so they can be recharged hundreds of times. Maximizing the performance of all these materials at the same time is a longstanding goal of battery research, yet in practice, improvements in one usually come at the expense of the others.

“A typical trade-off lies in the storage capacity and rate capability of the electrode material,” co-team leader Hengxing Ji tells Physics World. “For example, anode materials with high lithium storage capacity, such as silicon, are usually reported as having low lithium-ion conductivity, which hinders fast battery [charging]. As a result, the increase in battery capacity usually leads to a long charging time, which represents a critical roadblock for more widespread adoption of EVs.”

Black phosphorus composite makes a better battery, Isabelle Dumé, Physics World

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Clusters...

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Image Source: Link below

Topics: Biology, COVID-19, Research

Continued: It triggered a big outbreak. At least 97 people who attended the conference, or lived in a household with someone who did, tested positive.

The Biogen meeting had become a superspreading event. Eventually, the virus spread from the meeting across Massachusetts and to other states. A recent study estimates it led to tens of thousands of cases in the Boston area alone.

Superspreading

COVID-19 superspreading events have been reported around the world. They happen in all sorts of places: bars and barbecues, gyms and factories, schools and churches, and on ships.

And even at the White House.

But why do these disease clusters occur—and why are they so important?

The reproduction rate

COVID-19 and many other diseases transmit from person to person. The reproduction rate, R, determines how fast a disease can spread.

R denotes the number of people infected, on average, by a single infected person. If R is 2, the number of cases doubles in every generation: from one infected person to two, to four, to eight, and so on.

The Science of Superspreading, Martin Enserink, Kai Kupferschmidt, and Nirja Desai, Science Magazine

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Quadrupedal Robots...

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Image Source: Link below

Topics: Autonomous Vehicles, Mechanical Engineering, Research, Robotics

Abstract

Legged locomotion can extend the operational domain of robots to some of the most challenging environments on Earth. However, conventional controllers for legged locomotion are based on elaborate state machines that explicitly trigger the execution of motion primitives and reflexes. These designs have increased in complexity but fallen short of the generality and robustness of animal locomotion. Here, we present a robust controller for blind quadrupedal locomotion in challenging natural environments. Our approach incorporates proprioceptive feedback in locomotion control and demonstrates zero-shot generalization from simulation to natural environments. The controller is trained by reinforcement learning in simulation. The controller is driven by a neural network policy that acts on a stream of proprioceptive signals. The controller retains its robustness under conditions that were never encountered during training: deformable terrains such as mud and snow, dynamic footholds such as rubble, and overground impediments such as thick vegetation and gushing water. The presented work indicates that robust locomotion in natural environments can be achieved by training in simple domains.

Learning quadrupedal locomotion over challenging terrain, Joonho Lee1, Jemin Hwangbo 1,2, Lorenz Wellhausen1, Vladlen Koltun3, and Marco Hutter1

Science Robotics  21 Oct 2020:
Vol. 5, Issue 47, eabc5986
DOI: 10.1126/scirobotics.abc5986

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NEMS Photothermal Microscopy...

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Topics: Microscopy, Nanotechnology, NEMS, Physics, Research

Single-molecule microscopy has become an indispensable tool for biochemical analysis. The capability of characterizing distinct properties of individual molecules without averaging has provided us with a different perspective for the existing scientific issues and phenomena. Recently, super-resolution fluorescence microscopy techniques have overcome the optical diffraction limit by the localization of molecule positions. However, the labeling process can potentially modify the intermolecular dynamics. Based on the highly sensitive nanomechanical photothermal microscopy reported previously, we propose optimizations on this label-free microscopy technique toward localization microscopy. A localization precision of 3 Å is achieved with gold nanoparticles, and the detection of polarization-dependent absorption is demonstrated, which opens the door for further improvement with polarization modulation imaging.

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FIG. 2. (a) Schematic of the measurement setup. BE: beam expander. M: mirror. WP: waveplate. LP: linear polarizer. BS: beam splitter. PD: photodetector/power meter. DM: dichroic mirror. ID: iris diaphragm. CCD: charge-coupled device camera. APD: avalanche photodiode detector. (b) The transduction scheme of the trampoline resonator. (c) SEM image of the trampoline resonator.

J. Appl. Phys. 128, 134501 (2020); https://doi.org/10.1063/5.0014905

Nanoelectromechanical photothermal polarization microscopy with 3 Å localization precision, Miao-Hsuan Chien and Silvan Schmid, Journal of Applied Physics

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Modeling Spread...

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Image Source: Coronavirus and COVID-19: What You Should Know (WebMD)

Topics: Biology, Computer Modeling, COVID-19, Research

TOKYO (Reuters) – A Japanese supercomputer showed that humidity can have a large effect on the dispersion of virus particles, pointing to heightened coronavirus contagion risks in dry, indoor conditions during the winter months.

The finding suggests that the use of humidifiers may help limit infections during times when window ventilation is not possible, according to a study released on Tuesday by research giant Riken and Kobe University.

The researchers used the Fugaku supercomputer to model the emission and flow of virus-like particles from infected people in a variety of indoor environments.

Air humidity of lower than 30% resulted in more than double the amount of aerosolized particles compared to levels of 60% or higher, the simulations showed.

The study also indicated that clear face shields are not as effective as masks in preventing the spread of aerosols. Other findings showed that diners are more at risk from people to their side compared to across the table, and the number of singers in choruses should be limited and spaced out.

Japan supercomputer shows humidity affects aerosol spread of coronavirus, Rocky Swift, Reuters Science

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B-TENG...

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Gentle breeze: illustration of the B-TENG triboelectric nanogenerator, which harvests electricity that is generated by fluttering polymer strips. (Courtesy: Xin Chen/Xiaojing Mu/Ya Yang)

Topics: Applied Physics, Nanotechnology, Polymers, Research

A new low-cost nanogenerator that can efficiently harvest electrical energy from ambient wind has been created by Ya Yang at the Beijing Institute of Nanoenergy and Nanosystems of the Chinese Academy of Sciences and colleagues. The team reports that the device achieves high electrical conversion efficiencies for breezes of 4–8 m/s (14–28 km/h) and says that it could be used to generate electricity in everyday situations, where conventional wind turbines are not practical.

As the drive to develop renewable sources of energy intensifies, there is growing interest in harvesting ambient energy in everyday environments. From breezes along city streets to the airflows created as we walk, the mechanical energy contained in ambient wind is abundant. The challenge is to harvest this every in an efficient and practical way. This has proven difficult using existing technologies such as piezoelectric films, which operate at very low power outputs.

Yang’s team based their new design around two well-known phenomena in physics. The first is the Bernoulli effect, which causes the fluttering of two adjacent flags to couple. If separated by a very small gap, the flags will flutter in-phase, while at slightly larger separations, they flap out-of-phase, and symmetrically about a central plane. The second is the triboelectric effect – the familiar phenomenon behind the “static electricity” that is created when different objects are rubbed together and then separated – resulting in opposite electrical charges on the objects and a voltage between the two.

Fluttering polymer ribbons harvest electrical energy, Physics World

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Infodemic...

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Topics: COVID-19, Existentialism, Research

I assure you, I have been affected by this pandemic more than most. I am in a demographic that can experience deleterious effects from this virus. I have had friends and family affected directly. I have classmates that are struggling to survive. This is no hoax: it's real.

My precautions are beyond anal.

I worked in cleanrooms in the semiconductor industry, the most stringent being Class 1. The old criteria meant 0.5 microns of particles per cubic feet of air. (The newest guidelines were adopted in 2001, metric and still pretty stringent.) Each employee passed through air showers to push off any particulates from their clothing. Smokers are encouraged not to indulge, and cologne was prohibited - smoke and scent are particles. We then put our street garb in a locker, putting on green hospital gowns and fab shoes that never left the site. Then we donned cleanroom gowns - "bunny suits" - before going into the alien, HEPA-filtered environment, protecting it from any hair, skin, sweat, or dirt we could shed that would inhibit the functionality of integrated circuits. I tried to drink as little water as possible before going on the floor. Going to the bathroom, or lunch was a pain.


I have developed a unique protocol for assaulting what used to be trivial things like getting the mail, mowing the lawn - grass grows as rains fall during pandemics - or, going to the grocers for supplies.


1. I fashioned a mask from my father's handkerchiefs and rubber bands per the CDC guidelines. (I now have a collection of 5).

2. I use cloth/rubber work gloves for mowing as the rubber is tactile enough for me to operate equipment and pay for items at the grocery store.

3. After I enter the house, I immediately put all clothing - including my gloves - in the washer. I proceed to the shower.

Source: https://physics4thecool.blogspot.com/2020/04/protocols.html

The confluence of misinformation and infectious disease isn’t unique to COVID-19. Misinformation contributed to the spread of the Ebola epidemic in West Africa, and it plagues efforts to educate the public on the importance of vaccinating against measles. But when it comes to COVID-19, the pandemic has come to be defined by a tsunami of persistent misinformation to the public on everything from the utility of masks and the efficacy of school closures, to the wisdom behind social distancing, and even the promise of untested remedies. According to a study published by the National Bureau of Economic Research, areas of the country exposed to television programming that downplayed the severity of the pandemic saw greater numbers of cases and deaths—because people didn’t follow public health precautions.

In the United States, misinformation spread by elements of the media, by public leaders, and by individuals with large social media platforms has contributed to a disproportionately large share of COVID-19 burden: we house 4 percent of the global population but account for 22 percent of global COVID-19 deaths. With winter around the corner and people spending more time indoors, it is more imperative than ever that we counter misinformation and clearly communicate risks to the public; in addition, as we await the arrival of a vaccine, it is equally important to arm the public with facts. We have work to do: a recent poll found that just half of the American public plans to get a COVID-19 vaccine.

COVID Misinformation Is Killing People - This “infodemic” has to stop

Amir Bagherpour, Ali Nouri, Scientific American

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Fit...

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Reflective markers are attached to blue 3D-printed apparatus above and below the user’s knee as well as two metal plates on the exoskeleton leg. Researchers track and compare the movement of the markers to gain insight into how well the exoskeletons fit. In this composite photo, the bottom plate has been added after the original image was taken to show the entire configuration.
Credit: N. Hanacek/NIST

Topics: Applied Physics, NIST, Research, Robotics

A shoddily tailored suit or a shrunken T-shirt may not be the most stylish, but wearing them is unlikely to hurt more than your reputation. An ill-fitting robotic exoskeleton on the battlefield or factory floor, however, could be a much bigger problem than a fashion faux pas. 

Exoskeletons, many of which are powered by springs or motors, can cause pain or injury if their joints are not aligned with the user. To help manufacturers and consumers mitigate these risks, researchers at the National Institute of Standards and Technology (NIST) developed a new measurement method to test whether an exoskeleton and the person wearing it are moving smoothly and in harmony. 

In a new report, the researchers describe an optical tracking system (OTS) not unlike the motion capture techniques used by filmmakers to bring computer-generated characters to life. 

The OTS uses special cameras that emit light and capture what is reflected back by spherical markers arranged on objects of interest. A computer calculates the position of the labeled objects in 3D space. Here, this approach was used to track the movement of an exoskeleton and test pieces, called “artifacts,” fastened to its user.

Exoskeleton Research Marches Forward With NIST Study on Fit, NIST

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Figure

The spike protein of the SARS-CoV-2 virus (gray) is shown with three small antibodies (pink) attached to its receptor binding domains. The spike attaches at the left to the viral membrane (not shown). DIAMOND LIGHT SOURCE

Topics: Chemistry, COVID-19, Physics, Research

As the world anxiously awaits development of one or more vaccines to tame the SARS-CoV-2 virus, other research continues at a feverish pace to find effective treatments for the disease it causes, COVID-19. That work, in which physicists and chemists are deeply involved, has made significant strides in the past several months and has turned up a few surprises. Researchers at the University of Alberta reported at the August virtual meeting of the American Crystallographic Association that a dipeptide-based protease inhibitor used to treat a fatal coronavirus infection in cats also blocks replication of the SARS-CoV-2 virus in samples of monkey lung tissue. Joanne Lemieux, a biochemist at the university, says the antiviral, known as GC373, works by blocking the function of the main protease (Mpro), an enzyme that cleaves the polyproteins translated from viral RNA into individual proteins once it enters human cells.

Lemieux says GC373 has been shown to have no toxic effects in cats. Anivive, a California company that develops pet medicines, has applied for US Food and Drug Administration approval to begin trials in humans. Lemieux’s group crystallized the Mpro in combination with the drug and produced three-dimensional images of how the drug binds strongly to the active pocket on the enzyme. Although GC373 should be effective in its current form, the group is planning further crystallography experiments at the Stanford Synchrotron Radiation Lightsource (SSRL) and the Canadian Light Source to see if a reformulation could optimize it for human use, she says.

Cats and llamas could offer a path to coronavirus therapies, David Kramer, Physics Today

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Plasma Guides and Lasers...

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Lasers are used to create an indestructible optical fiber out of plasma.

Credit: Intense Laser-Matter Interactions Lab, University of Maryland

Topics: Lasers, Optics, Plasma, Research, Star Trek, Star Wars

In science fiction, firing powerful lasers looks easy — the Death Star can just send destructive power hurtling through space as a tight beam. But in reality, once a powerful laser has been fired, care must be taken to ensure it doesn’t get spread too thin.

If you’ve ever pointed a flashlight at a wall, you’ve observed an example of the diffusion of light. The farther you are from the wall, the more the beam spreads, resulting in a larger and dimmer spot of light. Lasers generally expand much more slowly than the beams from flashlights, but the effect of diffusion is important when the laser travels a long way or must maintain a high intensity.

Whether your goal is to achieve galactic domination or, more realistically, to accelerate electrons to incredible speeds for physics research, you’ll want as tight and powerful a beam as possible to maximize the intensity.

In their experiments, researchers can use devices called waveguides, like the optical fibers that might be carrying the internet throughout your neighborhood, to transport lasers while keeping them contained to narrow beams.

Plasma guides maintain focus of lasers, National Science Foundation Public Affairs

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APS...

Topics: COVID-19, Materials Science, Optics, Photonics, Research

From chemistry to materials science to COVID-19 research, the APS is one of the most productive X-ray light sources in the world. An upgrade will make it a global leader among the next generation of light sources, opening new frontiers in science.

In the almost 25 years since the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science User Facility, first opened at DOE’s Argonne National Laboratory, it has played an essential role in some of the most pivotal discoveries and advancements in science.

More than 5,000 researchers from around the world conduct experiments at the APS every year, and their work has, among many other notable successes, paved the way for better renewable batteries; resulted in the development of numerous new drugs; and helped to make vehicles more efficient, infrastructure materials stronger and electronics more powerful.

Advanced Photon Source Upgrade will transform the world of scientific research, Brett Hansard, Argonne National Laboratory

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Touchless Print Scanning...

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Credit: N. Hanacek/NIST NIST evaluated several commercially available contactless fingerprint scanning technologies in its May 2020 report.

 

Topics: NIST, Optics, Research

The National Institute of Standards and Technology (NIST) has evaluated several commercially available contactless fingerprint scanning technologies, allowing users to compare their performance to conventional devices that require physical contact between a person’s fingers and the scanner.

The results of the study, published today as NIST Interagency Report (NISTIR) 8307: Interoperability Assessment 2019: Contactless-to-Contact Fingerprint Capture, show that devices requiring physical contact remain superior to contactless technology at matching scanned prints to images in a database. However, when contactless devices scan multiple fingers on a hand, it improves their performance. Contactless devices that scanned multiple fingers also seldom made “false positive” errors that incorrectly matched one person’s print with another’s record.

The publication updates NIST’s July 2018 study on contactless capture and is intended to assist organizations that use fingerprint-scanning technology.

“The report summarizes the state of the art of contactless fingerprint scanning,” said John Libert, one of the report’s authors. “It can help anyone interested in adopting contactless technology to evaluate the cost in performance they might pay by switching to contactless fingerprint capture.”

NIST Study Measures Performance Accuracy of Contactless Fingerprinting Tech

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Kondo Effect...

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Daniel Mazzone led the project to explore the mechanism that causes samarium sulphide to expand dramatically when cooled. Credit: Brookhaven National Laboratory

 

Topics: Materials Science, Quantum Mechanics, Research, Thermodynamics

Most metals expand when heated and contract when cooled. A few metals, however, do the opposite, exhibiting what’s known as negative thermal expansion (NTE). A team of researchers led by Ignace Jarrige and Daniel Mazzone of Brookhaven National Laboratory in the US has now found that in one such metal, yttrium-doped samarium sulphide (SmS), NTE is linked to a quantum many-body phenomenon called the Kondo effect. The work could make it possible to develop alloys in which positive and negative expansion cancel each other out, producing a composite material with a net-zero thermal expansion – a highly desirable trait for applications in aerospace and other areas of hi-tech manufacturing.

Even within the family of NTE materials, yttrium-doped SmS is an outlier, gradually expanding by up to 3% when cooled over a few hundred degrees. To better understand the mechanisms behind this “giant” NTE behavior, Mazzone and Jarrige employed X-ray diffraction and spectroscopy to investigate the material’s electronic properties.

The researchers carried out the first experiments at the Pair Distribution Function (PDF) beamline at Brookhaven’s National Synchrotron Light Source (II) (NSLS-II). They placed their SmS sample inside a liquid-helium cooled cryostat in the beam of the synchrotron X-rays and measured how the X-rays scattered off the electron clouds around the atomic ions. By tracking how these X-rays scatter, they identified the locations of the atoms in the crystal structure and the spacings between them.

“Our results show that, as the temperature drops, the atoms of this material move farther apart, causing the entire material to expand by up to 3% in volume,” says Milinda Abeykoon, the lead scientist on the PDF beamline.

Kondo effect induces giant negative thermal expansion, Belle Dumé, Physics World

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YULIA DROZDOVA/ALAMY STOCK VECTOR
 

Topics: History, Politics, Research, STEM

 

A crowd began to form at the train station in Pocatello, Idaho, around 5:15 am on Wednesday, 10 May 1950. Some 700 bleary-eyed townspeople had come to see the president and neither the day’s cold weather nor the hour would deter them. When the train chugged into town, President Harry Truman was standing on the rear platform, ready to greet the crowd. The trip to Pocatello was part of a whistle-stop tour of the northern US that took the president to numerous small towns dotting the railway.

Although Truman spent most of his time in Idaho addressing local agricultural and economic issues, in Pocatello, he talked to the crowd about science. Earlier that morning, as his train sped along the tracks, Truman had signed the National Science Foundation Act of 1950. It created the first federal agency devoted to supporting fundamental research and education across all scientific disciplines. Standing before a group of chilly Idahoans, Truman made a case for the importance of large-scale federal support for scientific research.

The story of NSF’s creation and early years of operation serves as an important window into the growth of postwar federal science policy. Science’s role in World War II had convinced many in the government that public support was needed for scientific research. Once open, NSF became an important site where debates over science policy, federal support for civilian research facilities, and federal support for education in STEM (science, technology, engineering, and mathematics) played out in postwar America.

NSF and postwar US Science, Emily Gibson, Physics Today

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Silicon Sees the Light...

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Silicon sees the light: Elham Fadaly (left) and Alain Dijkstra in their Eindhoven lab. (Courtesy: Sicco van Grieken/SURF)

 

Topics: Optics, Electrical Engineering, Nanotechnology, Research, Solar Power, Spectroscopy


A light-emitting silicon-based material with a direct bandgap has been created in the lab, fifty years after its electronic properties were first predicted. This feat was achieved by an international team led by Erik Bakkers at Eindhoven University of Technology in the Netherlands. They describe the new nanowire material as the “Holy Grail” of microelectronics. With further work, light-emitting silicon-based devices could be used to create low-cost components for optical communications, computing, solar energy and spectroscopy.

Silicon is the wonder material of electronics. It is cheap and plentiful and can be fabricated into ever smaller transistors that can be packed onto chips at increasing densities. But silicon has a fatal flaw when it comes to being used as a light source or solar cell. The semiconductor has an “indirect” electronic bandgap, which means that electronic transitions between the material’s valence and conduction bands involve vibrations in the crystal lattice. As a result, it is very unlikely that an excited electron in the conduction band of silicon will decay to the valence band by emitting light. Conversely, the absorption of light by silicon does not tend to excite valence electrons into the conduction band – a requirement of a solar cell.

 

Silicon-based light emitter is ‘Holy Grail’ of microelectronics, say researchers
Hamish Johnston, Physics World

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Dilemma...

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Green Book Blog: The Technology Dilemma, Zoë Dowling

 

Topics: Biology, Chemistry, COVID-19, Nanotechnology, Physics, Research, STEM


As the coronavirus outbreak roils university campuses across the world, early-career scientists are facing several dilemmas. Many are worrying about the survival of cell cultures, laboratory animals, and other projects critical to their career success. And some are reporting feeling unwelcome pressure to report to their laboratories—even if they don’t think it’s a good idea, given that any gathering can increase the risk of spreading the virus.

It’s unclear exactly how common these concerns are, but social media posts reveal numerous graduate students expressing stress and frustration at requests to come to work. “Just emailed adviser to say I am not comfortable breaking self isolation to come to lab this week. They emailed … saying I have to come in. What do I do?” tweeted an anonymous Ph.D. student on 16 March who doesn’t have essential lab work scheduled. “My health & safety should NOT be subject to the whims of 1 person. It should NOT be this scary/hard to stand up for myself.”

Many universities, including Harvard, have moved to shut down all lab activities except for those that are deemed “essential,” such as maintaining costly cell lines, laboratory equipment, live animals, and in some cases, research relating to COVID-19. But others have yet to ban nonessential research entirely.

 

Amid coronavirus shutdowns, some grad students feel pressure to report to their labs
Michael Price, Science Magazine, AAAS

I feel their pain.


The Scientific Method is very simple in concept:

Problem research - This involves gathering data in the form of previous written papers, published and peer-reviewed; writing notes (for yourself), summaries and reviews.

Hypothesis - This is your question asked from all the research, discussion with your adviser, especially if it's a valid question to ask or research to pursue.

Test the hypothesis - Design of experiment (s) to verify the hypothesis.

Data analysis - Usually with a software package, and a lot of statistical analysis.

Conclusion - Does it support the hypothesis?

- If so, retest several times, to plot an R squared fit of the data, so predictions can be made.

- If not, form another hypothesis and start over.

Often, conclusions are written up for peer review to be considered for journal publication. No one ever gets in on first submission - get used to rejection. Conclusions will be challenged by subject matter experts that may suggest other factors to consider, or another way to phrase something. Eventually, you get published. You can then submit an abstract to present a poster and a talk at a national conference.

Meeting Cancellation

It is with deep regret that we are informing you of the cancellation of the 2020 APS March Meeting in Denver, Colorado. APS leadership has been monitoring the spread of the coronavirus disease (COVID-19) constantly. The decision to cancel was based on the latest scientific data being reported, and the fact that a large number of attendees at this meeting are coming from outside the US, including countries where the CDC upgraded its warning to level 3 as recently as Saturday, February 29.

 

APS Physics: March.APS/about/coronavirus/


Update on Coronavirus

The health and safety of MRS members, attendees, staff, and community are our top priority. For this reason, we are canceling the 2020 MRS Spring Meeting scheduled for April 13-17, 2020, in Phoenix.

With our volunteers, we are exploring options for rescheduling programming to an upcoming event. We will share more information as soon as it becomes available.

 

MRS: Materials Research Society/2020-Spring Meeting


Social distancing and "shelter-in-place" slows the scientific enterprise. Science is in-person and worked out with other humans in labs and libraries. However, I am in support of this action and reducing the impact on the healthcare industry that on normal days are dealing with broken bones, gunshot wounds; cancer and childbirth surgeries with anxious, expectant mothers.

The dilemma is the forces that would reject the science behind this pandemic (and most science in any endeavor), would have us all "go back to work" after two weeks. The curve we're trying to flatten could sharply spike. The infection rates would increase and otherwise healthy people would be stricken. Immunodeficient groups would start getting sick again ...dying again. Our infrastructure is not designed for that many sick or dead people. Science continues with our survival and societal stability.

The persons with the solutions might be chomping-at-the-bit at home for now. Survival insures science will continue ...someday.
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