• share
• favorite_border

As the pandemic continues, researchers have increasingly focused on the extent to which respiratory droplets carrying the coronavirus travel and contaminate the air after an infected person coughs. While scientists have studied the properties of air at the mouth, less is known about how these properties change as the cough cloud travels. In Physics of Fluids, researchers estimate the evolving volume of the cough cloud and quantify the reduction in its volume in the presence of a face mask.

• share
• favorite_border

Scientists at the University of Delaware report a computational study of a nucleocapsid found in the Ebola virus and show that the binding of the ssRNA allows the nucleocapsid to maintain its shape and structural integrity.

• share
• favorite_border

Flow velocity distribution and particle size are key in aerosol transport, which is one of the main ways COVID-19 spreads, when aerosol particles are released during exhalation, talking, coughing, or sneezing. In Physics of Fluids, University of New Mexico researchers used computational fluid-particle dynamics to explore aerosol transport within an air-conditioned classroom model. They discovered opening windows increases the fraction of particles that exit the system by nearly 40%, while also reducing aerosol transmission between people within.

• share
• favorite_border

The range of AI technologies available for dealing with brain disease is growing fast, and exciting new methods are being applied to brain problems as computer scientists gain a deeper understanding of the capabilities of advanced algorithms. In APL Bioengineering, Italian researchers conducted a systematic literature review to understand the state of the art in the use of AI for brain disease. Their qualitative review sheds light on the most interesting corners of AI development.

• share
• favorite_border

Wound dressing, tissue scaffolding, controlled and sustained drug delivery, and cardiac patching are all biomedical processes requiring a material that combines strength with functionality. Core-sheath polymer fibers, fibers comprised of a strong core surrounded by a biologically applicable sheath layer, are an affordable way to meet these requirements. In the journal Applied Physics Reviews, researchers discuss methods of producing core-sheath polymer fibers and their promising applications.

• share
• favorite_border

Powerful picosecond generators are in demand in various fields of experimental electrophysics to produce ultrashort electron beams and X-ray pulses in vacuum diodes and to form runaway electron flows in gases and researchers are constantly striving to obtain shorter and more powerful pulses. In Review of Scientific Instruments, scientists showed compact solid-state pulse generators could generate electrical pulses of less than one-billionth of a second in duration and up to 50 billion watts in power.

• share
• favorite_border

The American Institute of Physics and the American Physical Society announce Joel Lebowitz, director of the Center for Mathematical Sciences Research at Rutgers University, as the recipient of the 2021 Dannie Heineman Prize for Mathematical Physics. The citation on the award reads: "for seminal contributions to nonequilibrium and equilibrium statistical mechanics, in particular, studies of large deviations in nonequilibrium steady states and rigorous analysis of Gibbs equilibrium ensembles."

• share
• favorite_border

The 2020 Nobel Prize in physics was awarded to Roger Penrose, Reinhard Genzel, and Andrea Ghez, for their work on black holes, described by the Nobel committee as “the darkest secrets in the universe.” To help journalists and the public understand the context of this work, AIP is compiling a Nobel Prize resources page featuring relevant scientific papers and articles, quotes from experts, photos, multimedia, and other resources. The page will be updated throughout the day.

• share
• favorite_border

Hydrogen is becoming a crucial pillar in the clean energy movement, and developing safe and cost-effective storage and transportation methods for it is essential but complicated, because hydrogen can cause brittleness in several metals including ferritic steel. Recent advancements are starting to provide insight into the embrittlement process. A review of various methods in Applied Physics Reviews improves the understanding of the structure, property, and performance of ferritic steels subjected to mechanical loading in a hydrogen environment.

• share
• favorite_border

The American Institute of Physics welcomes Taharee Jackson as its first AIP Diversity, Equity, and Belonging Officer. Jackson is expected to begin her new role on Oct. 5. Jackson’s appointment is a direct result of AIP’s commitment to emphasizing diversity and inclusion in the federation and throughout the physics and physical sciences community. She was selected from an initial pool of more than 60 candidates and is looking forward to leading AIP’s diversity efforts.

• share
• favorite_border

France Córdova, former director of the National Science Foundation, NASA chief scientist, and president of Purdue University, has been appointed as the first chair of the newly formed AIP Foundation. The Foundation was established to support the charitable, scientific, and educational mission of the American Institute of Physics by amplifying philanthropic support of the Institute, bolstering and innovating funding models for AIP programs and activities and supporting the Institute’s overarching strategy of advancing the physical sciences with a unifying voice of strength from diversity.

• share
• favorite_border

Parkinson’s disease is most commonly treated with levodopa, but the benefits wear off as the disease progresses and high doses can result in dyskinesia, which are involuntary and uncontrollable movements. To better understand the underlying reasons behind these effects, researchers created a model of the interactions between levodopa, dopamine, and the basal ganglia, an area of the brain that plays a crucial role in Parkinson’s disease. They discuss their findings in the journal Chaos.

• share
• favorite_border

If you have been surrounded by the sight and smell of pine trees, you may have taken a closer look at the needles and then wondered how their properties are influenced by rainfall. In Physics of Fluids, researchers are currently probing how well pine needles allay the impact of rain beneath the tree. They explored the impact of raindrops onto fixed, noncircular fibers of the longleaf pine by using high-speed videography to capture the results.

• share
• favorite_border

Michael Moloney, CEO of the American Institute of Physics, was elected a 2020 Fellow of the American Physical Society as recognition of his outstanding contributions to physics. The citation reads, “For exceptional contributions to physics research enterprise and science policy as overseer of studies conducted by the National Academies of Sciences boards on Space, and Physics and Astronomy, and by the National Materials Advisory Board; and for visionary leadership as CEO of the American Institute of Physics.”

• share
• favorite_border

A new Lyne Starling Trimble Science Heritage Public Lecture Series begins with six speakers, who are scheduled for online talks in late 2020-early 2021. The first lecture in the series will be held Sept. 30 and will be streamed online with an interactive question-and-answer period after the talk. During the series, science historians and writers will highlight important roles science has played in modern society, including in robotic development, WWII espionage, and technical accomplishments.

• share
• favorite_border

Producing biogas from the bacterial breakdown of biomass presents options for a greener energy future, but the complex composition of biomass comes with challenges. Cellulose and woody lignocellulose are especially hard for bacteria to digest but pretreatment can make it easier. Researchers are testing plasma formation in biomass and finding a promising method: A plasma-liquid interaction forms reactive species that help break down the biomass and decrease the viscosity of the biomass material.

• share
• favorite_border

As the COVID-19 pandemic continues, some locations have experienced decreasing numbers of cases followed by an increase. In the journal Chaos, mathematicians report a method to analyze these numbers for evidence of a first or second wave. The authors studied data from all 50 U.S. states plus D.C. for the seven-month period from Jan. 21 to July 31. They found 31 states and D.C. were experiencing a second wave as of the end of July.

• share
• favorite_border

As COVID-19 cases continue to rise, it is increasingly urgent to understand how climate impacts the spread of the coronavirus, particularly as winter virus infections are more common and the northern hemisphere will soon see cooler temperatures. In Physics of Fluids, researchers studied the effects of relative humidity, environmental temperature, and wind speed on the respiratory cloud and virus viability. They found a critical factor for the transmission of the infectious particles is evaporation.

• share
• favorite_border

The star HL Tauri, 450 light-years from Earth, is glowing at the center of a system of concentric rings made from gas and dust and producing planets, one for each gap in the ring. Its discovery has shaken solar system origin theories to their core. Mayer Humi, a scientist from the Worcester Polytechnic Institute, believes it provides an apt study target for theories about protoplanetary rings around stars. The research is published in the Journal of Mathematical Physics.

• share
• favorite_border

The race is on to create natural biocompatible piezoelectric materials for energy harvesting, electronic sensing, and stimulating nerves. Researchers decided to explore peptide-based nanotubes, and in the Journal of Applied Physics, they report using a combination of ultraviolet and ozone exposure to generate a wettability difference and an applied field to create horizontally aligned polarization of nanotubes on flexible substrates with interlocking electrodes. The group’s work will enable the use of organic materials more widely.

• share
• favorite_border

Fish and seaweed secrete a layer of mucus to create a slippery surface, reducing their friction as they travel through water. A potential way to mimic this is by creating lubricant-infused surfaces covered with cavities. As the cavities are continuously filled with the lubricant, a layer is formed over the surface. In the journal Physics of Fluids, researchers in South Korea conducted simulations of this process to help explain the effects.

• share
• favorite_border

COVID-19 is caused by the virus SARS-CoV-2, which is structurally similar to the viruses that cause SARS-CoV and MERS-CoV. In The Journal of Chemical Physics, scientists report molecular-level investigations of these viruses, providing a possible pathway to antiviral drugs to fight the diseases. They looked at a viral protein that plays a role in the virus’s ability to replicate and in defeating the host’s immune system, making it an attractive target for potential drug treatments.

• share
• favorite_border

The American Institute of Physics is still accepting nominations for the 2020 John Torrence Tate Medal for International Leadership in Physics. The deadline to apply is Oct. 1, 2020. The medal was established in 1959 and is awarded every two years to non-U.S. citizens for their leadership, research contributions and service to the international physics community. The award consists of a certificate of recognition, a bronze medal, and a $10,000 prize.

• share
• favorite_border

Hepatocellular carcinoma is usually treated by blocking the flow of blood to the tumor to induce cancer cell death, but the common treatment, transarterial chemoembolization, is invasive and too imprecise to be a local drug delivery method. Aiming to increase the precision, researchers at Tulane University created a treatment that involves vaporizing tiny droplets of perfluorocarbon, a common organic material composed of carbon and fluorine. The method of gas embolization is published in APL Bioengineering.

• share
• favorite_border

Inspired by the need for new and better therapies for neurodegenerative diseases, Rutgers University researchers are exploring the link between uncontrolled inflammation within the brain and the brain’s immune cells, known as microglia, which are emerging as a promising cellular target because of the prominent role they play in brain inflammation. In APL Bioengineering, the group highlights the design considerations and benefits of creating therapeutic nanoparticles for carrying pharmacological factors directly to the sites of the microglia.

• share
• favorite_border

N95 masks achieve 95% efficiency at filtering out tiny 0.3-micron particles, while maintaining reasonable breathability, thanks to a layer of polypropylene fibers incorporating electrical charges to attract particles. Extended usage and decontamination, provoked by severe shortages during the pandemic, can easily remove the charges and degrade filtration efficiency. In Physics of Fluids, researchers share a method to restore the filtration efficiency of N95 masks to out-of-box levels, as long as the mask is not structurally compromised.

• share
• favorite_border

When looking at humanity from a macroscopic perspective, there are numerous examples of people cooperating to form various groupings. Yet at the basic two-person level, people tend to betray each other, as found in games like the prisoner’s dilemma, even though people would receive a better payoff if they cooperated among themselves. The topic of cooperation and how and when people start trusting one another has been studied numerically, and in a paper in Chaos, researchers investigate what drives cooperation analytically.

• share
• favorite_border

Glass windows typically offer some amount of sound proofing, sometimes unintentionally. In general, ventilation is required to achieve large sound transmission. But some applications -- like gas explosion studies -- require a transparent partition that allows for acoustic propagation without the presence of airflow. In those cases, ventilation is not allowed. In Applied Physics Letters, researchers discuss a layered glass material they developed that allows for efficient sound transmission with no air ventilation.

• share
• favorite_border

Diagnostic devices that are used at home or in doctors’ offices are often not sensitive enough to detect small amounts of a virus that might be present in samples from asymptomatic patients, which can occur in early stage COVID-19. In Biomicrofluidics, scientists report a membrane-based invention that can concentrate the virus content of a sample of urine or saliva, allowing it to be detected.

• share
• favorite_border

As countries experience a steep surge in COVID-19 infections, face masks have become increasingly accepted as an effective means for combating the spread of the disease when combined with social distancing and frequent hand-washing. Increasingly people are using clear plastic face shields and masks with exhalation valves instead of regular cloth or surgical masks, since they can be more comfortable. In a paper published in Physics of Fluids, researchers investigate whether they are as effective.

• share
• favorite_border

If the mist in a dentist’s office -- sent flying into the air by spinning, vibrating tools -- contains a virus or some other pathogen, it is a health hazard for dentists and patients. So researchers in Illinois studied the viscoelastic properties of food-grade polymers and discovered that the forces of a vibrating tool or dentist’s drill are no match for them. Not only did a small admixture of polymers completely eliminate aerosolization, but it did so with ease.

• share
• favorite_border

Months into the COVID-19 pandemic, wearing a mask while out in public has become the recommended practice. However, many still question the effectiveness of this. To allay doubts, Padmanabha Prasanna Simha, from the Indian Space Research Organisation, and Prasanna Simha Mohan Rao, from the Sri Jayadeva Institute of Cardiovascular Sciences and Research, experimentally visualized the flow fields of coughs under various common mouth covering scenarios. They present their findings in the journal Physics of Fluids.

• share
• favorite_border

Origami can be used to create mechanical, binary switches, and in Applied Physics Letters, researchers report the fabrication of such a paper device, using the Kresling pattern, that can act as a mechanical switch. By putting several together on a single platform, the investigators built a functioning mechanical memory board. They found that oscillating the platform up and down at a certain speed will cause it to flip, or switch, between its two stable states.

• share
• favorite_border

The American Institute of Physics announced artist Geraldine Cox as the winner of the 2020 Andrew Gemant Award. The award is given annually to recognize individuals who have made significant contributions to the cultural, artistic or humanistic dimension of physics. The selection committee cited her “for articulating deep physics concepts through visual arts and other media, reaching a remarkable range of people in innovative ways and sharing her passion for the expression of physical truths.”

• share
• favorite_border

Think you don’t need to worry about COVID-19 while using a public restroom? Researchers from Yangzhou University in China recently reported that flushing public restroom toilets can release clouds of virus-laden aerosols for you to potentially inhale. If that’s not cringeworthy enough, after running additional computer simulations, they’ve concluded that flushing urinals does likewise. In Physics of Fluids, the group shares its work simulating and tracking virus-laden particle movements when urinals are flushed.

• share
• favorite_border

As the climate of the planet is changing, many researchers are looking to more renewable energy sources. In the Journal of Sustainable and Renewable Energy, researchers investigate whether the power generated by solar and wind farms would differ between current and future climates. The researchers focused on sites in Australia where variable renewable generators are located or are likely to be located in the future based on the Australian Energy Market Operator’s system plan.

• share
• favorite_border

The novel coronavirus that causes COVID-19 is thought to spread through natural respiratory activities, but little is known about how the virus is transported through the air. Scientists report in Physics of Fluids on a study of how airflow and fluid flow affect exhaled droplets that can contain the virus. Their model includes a more accurate description of air turbulence that affects an exhaled droplet’s trajectory. Calculations with their model reveal, among other things, an important and surprising effect of humid air.

• share
• favorite_border

Trace vapor detection technologies are crucial for ensuring reliable and safe detection of explosives and illegal drugs. Researchers have developed a compact testing device called the Trace Vapor Generator for Explosives and Narcotics, which is portable and can be used for non-contact sampling of these vapors. In Review of Scientific Instruments, the team reports the TV-Gen can accurately generate trace vapors of low vapor pressure compounds and can produce vapors in complex backgrounds.

• share
• favorite_border

Michael Moloney, CEO of AIP, joins the Center for the Advancement of Science in Space as a member of their board of directors in their efforts to optimize the use of the International Space Station U.S. National Laboratory. The laboratory is used “for improving quality of life on Earth, promoting collaboration among diverse users, and advancing science, technology, engineering, and mathematics (STEM) education.” Moloney joins three other new members on the board of directors: Eric D. Isaacs, Elizabeth R. Cantwell and Gale J. Allen.

• share
• favorite_border

In severe cases of COVID-19, damage can spread beyond the lungs and into other organs, such as the heart, liver, kidney and parts of the neurological system. Beyond these specific sets of organs, however, the virus seems to lack impact. Ernesto Estrada aimed to uncover an explanation as to how it is possible for these damages to propagate selectively rather than affecting the entire body. He discusses his findings in the journal Chaos.

• share
• favorite_border

Since the COVID-19 virus spreads through respiratory droplets, researchers in India set out to explore how droplets deposited on face masks or frequently touched surfaces dry. Droplets can be expelled via the mouth or nose and studies have shown a substantially reduced chance of infection once they dry. In Physics of Fluids, the researchers publish their findings that surface wetting properties to reduce the drying time of droplets could help lessen the risk of infection from coronaviruses.

• share
• favorite_border

As we use resources to power massive computer farms and process digital information, our technological progress is redistributing Earth’s matter from physical atoms to digital information. Eventually, we will reach a point of full saturation, a period in our evolution in which digital bits will outnumber atoms on Earth, a world “mostly computer simulated and dominated by digital bits and computer code,” according to an article published in AIP Advances. It is just a matter of time.

• share
• favorite_border

In Physics of Fluids, scientists report calculations with a model of a conical-shaped root canal inside a tooth. A crucial step in this common dental procedure is irrigation, or rinsing, of the root canal cavity with an antibacterial solution, and the researchers used computational fluid dynamics to determine the effect of temperature on the cleaning efficiency: Higher temperatures can, to a point, improve cleansing, but this benefit falls off if the temperature gets too high.

• share
• favorite_border

Researchers have been working for decades on improving the anti-icing performance of functional surfaces and work published in AIP Advances investigates a unique nanostructure, modeled on moth eyes, that has anti-icing properties. Moth eyes are of interest because they have a distinct ice-phobic and transparent surface. The researchers fabricated the moth eye nanostructure on a quartz substrate that was covered with a paraffin layer to isolate it from a cold and humid environment.

• share
• favorite_border

If aerosol transmission of COVID-19 is confirmed to be significant, as suspected, we will need to reconsider guidelines on social distancing, ventilation systems and shared spaces. Researchers in the U.K. believe a better understanding of different droplet behaviors and their different dispersion mechanisms is also needed. In Physics of Fluids, the group presents a model that demarcates differently sized droplets. This has implications for understanding the spread of airborne diseases, because the dispersion tests revealed the absence of intermediate-sized droplets.

• share
• favorite_border

Through convection, as the liquid toward the bottom of a container warms up, it becomes less dense and moves to the top, allowing a cooler section of the liquid to contact the heating source. This ultimately results in a uniform temperature throughout the container. Inside a microwave, however, the electric field acting as the heating source exists everywhere and the convection process does not occur. Researchers studied this nonuniform heating behavior and present a solution in AIP Advances.

• share
• favorite_border

The American Institute of Physics is accepting nominations for the 2020 John Torrence Tate Medal for International Leadership in Physics. The deadline to apply is Oct. 1, 2020. The Tate medal was established in 1959 and is awarded every two years to non-U.S. citizens for their leadership, research contributions and service to the international physics community. The award consists of a certificate of recognition, a bronze medal and a $10,000 prize.

• share
• favorite_border

Many compact systems using mid-infrared technology continue to face compatibility issues when integrating with conventional electronics. Black phosphorus has garnered attention for overcoming these challenges thanks to a wide variety of uses in photonic circuits. Research published in Applied Physics Reviews highlights the material’s potential for emerging devices ranging from medical imaging to environment monitoring, assessing progress in different components of the chips, from light detection to laser emission.

• share
• favorite_border

Twitter mentions show distinct community structure patterns resulting from communication preferences of individuals affected by physical distance between users and commonalities, such as shared language and history. While previous investigations have identified patterns using other data, such as mobile phone usage and Facebook friend connections, research from the New England Complex Systems Institute looks at the collective effect of message transfer in the global community. The group’s results are reported in the journal Chaos.

• share
• favorite_border

Brazilian researchers demonstrated a new chemical approach for producing biodiesel from domestic cooking oil waste by using hydroxide lithium mixed with either sodium hydroxides or potassium hydroxides as catalysts. Their work, published in the Journal of Renewable and Sustainable Energy, could enable future studies related to the use of lithium from waste lithium ion batteries. The work marks one of the first times lithium has been used for such purposes.