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Comment by Dr. Krishna Kumari Challa on June 21, 2024 at 8:33am

Turning infrared light visible: New device uses 2D material to up-convert infrared light

The human eye can only see light at certain frequencies (called the visible spectrum), the lowest of which constitutes red light. Infrared light, which we can't see, has an even lower frequency than red light. Researchers at the Indian Institute of Science (IISc) have now fabricated a device to increase or "up-convert" the frequency of short infrared light to the visible range.

Up-conversion of light has diverse applications, especially in defense and optical communications. In a first, the IISc team used a 2D material to design what they call a non-linear optical mirror stack to achieve this up-conversion, combined with widefield imaging capability. The stack consists of multilayered gallium selenide fixed to the top of a gold reflective surface, with a silicon dioxide layer sandwiched in between.
Traditional infrared imaging uses exotic low-energy bandgap semiconductors or micro-bolometer arrays, which usually pick up heat or absorption signatures from the object being studied.

Infrared imaging and sensing is useful in diverse areas, from astronomy to chemistry. For example, when infrared light is passed through a gas, sensing how the light changes can help scientists tease out specific properties of the gas. Such sensing is not always possible using visible light.
However, existing infrared sensors are bulky and not very efficient. They are also export-restricted because of their utility in defense. There is, therefore, a critical need to develop indigenous and efficient devices.

The method used by the IISc team involves feeding an input infrared signal along with a pump beam onto the mirror stack. The nonlinear optical properties of the material constituting the stack result in a mixing of the frequencies, leading to an output beam of increased (up-converted) frequency, but with the rest of the properties intact. Using this method, they were able to up-convert infrared light of wavelength around 1550 nm to 622 nm visible light. The output light wave can be detected using traditional silicon-based cameras.

 Jyothsna Konkada Manattayil et al, 2D Material Based Nonlinear Optical Mirror for Widefield Up‐Conversion Imaging from Near Infrared to Visible Wavelengths, Laser & Photonics Reviews (2024). DOI: 10.1002/lpor.202400374

Comment by Dr. Krishna Kumari Challa on June 21, 2024 at 8:29am

Researchers discover why people who lack a specific blood group are genetically predisposed to be overweight or obese

A team of international researchers has discovered that people with a genetic variant that disables the SMIM1 gene have higher body weight because they expend less energy when at rest.

SMIM1 was only identified 10 years ago, while researchers were searching for the gene encoding a specific blood group, known as Vel. One in 5,000 people lack both copies of the gene, making them Vel-negative. The findings from the new research suggest that this group is also more likely to be overweight, a conclusion that could one day lead to new treatments.

The study found that people without both copies of the gene have other measures linked to obesity, including high levels of fat in the blood, signs of fat tissue dysfunction, increased liver enzymes as well as lower levels of thyroid hormones.

SMIM1 absence is associated with reduced energy expenditure and excess weight', Med (2024). DOI: 10.1016/j.medj.2024.05.015. www.cell.com/med/fulltext/S2666-6340(24)00219-8

Comment by Dr. Krishna Kumari Challa on June 21, 2024 at 8:23am

Improving crops with laser beams and 3D printing

A demonstration of how new technologies can be used in 21st century crop breeding comes from just published research that combines laser scanning and 3D printing to create a detailed 3D model of a sugar beet plant.

Taking the next step beyond having genetic information to guide intelligent breeding, the 3D plant models here capture the essential characteristics of the above-ground parts of the sugar beet plant and can be used for AI-assisted crop improvement pipelines. The sugar beet plant models are reproducible and fit for field use.

All the research information, data, methodology, as well as the 3D printing files are freely available. Crop management is gaining much needed tools, and, of course, everyone can now print their own 3D sugar beet plant (Minimum maintenance required.) The sugar beet plant 3D model and its validation are presented in a  new publication    in the journal GigaScience.

Jonas Bömer et al, A 3D printed plant model for accurate and reliable 3D plant phenotyping, GigaScience (2024). DOI: 10.1093/gigascience/giae035

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 11:12am

Personalized cancer vaccines are coming
The same mRNA technology that underpins COVID-19 vaccines could train the immune system to attack cancer cells. In a small trial, mRNA treatment in combination with an established immunotherapy nearly halved the risk of melanoma recurrence, compared with the immunotherapy on its own. We have the first proof of concept that these things can work, says cancer immunologists. Now, we just need to make them better. Key to this will be to predict which of the cancer cells’ mutant proteins — unique to each person and cancer type — the vaccine needs to target.

https://www.nature.com/articles/d41586-024-01717-x?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 9:24am

She recommends that travelers be more considerate in their choices of holiday destinations and reflect on the impact of their activities on the environment.

"Tourism should be defined by the local community, with decision-making controlled at the lowest level and an emphasis on the interrelationships between people, place, ecology and all living things. We need to slow down—stay longer, stay local, be thoughtful with our holiday choices," she says. "There are so many resources out there like Rise Travel Institute or The Travel Foundation that shed light on sustainable, responsible and just tourism.
It's about respecting the destination, looking out for codes of responsibility, and making yourself aware of the culture and what challenges the communities you're visiting are facing. I encourage people to try being more conscious on their next trip—stay in one place longer, travel more slowly, go for nature walks, engage with the culture, try to leave the destination a better place than how you found it."
Tourism Research Australia forecasts that over the next five years, domestic travel will see only moderate growth, largely due to increased competition from international outbound travel, which is set to continue to climb.

The tourism industry contributes 8% of total global carbon emissions, yet the Tourism Panel on Climate Change—an international body of climate scientists and tourism experts—focuses on profit-first climate-resilient tourism, rather than addressing the contribution of the industry to environmental destruction.
Dr. Higgins-Desbiolles says it's up to everyone to make more environmentally conscious travel decisions.

"We must see all governments willing to legislate and regulate tourism better. For example, France has passed legislation banning short-haul flights—the transport method contributing the second most to emissions—when a train journey of less than 2.5 hours is available," she says.

"Meaningful change is needed at every level; governments, organizations and travelers need to put their focus towards sustainable and climate-just tourism."

Freya Higgins-Desbiolles, The end of tourism? Contemplations of collapse, Journal of Tourism Futures (2024). DOI: 10.1108/JTF-11-2023-0259

Part 2

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 9:22am

Travelers urged to keep it local in the name of sustainable tourism

From rolling vineyards to stunning beaches, there's no shortage of beauty to discover in our own backyards.

A tourism expert from the University of South Australia is urging travelers to support local destinations and experiences close to home, instead of long-haul international trips, to lessen the impacts of tourism on the environment.

Adjunct Senior Lecturer in Tourism Management Dr. Freya Higgins-Desbiolles says we should be considering more localized travel and doing everything we can to reduce unnecessary emissions.

She says space travel, private jet travel and mass travel to far off and remote and extreme environments are "unethical" and contribute to a culture of privileged over-consumption.

"In these conditions, it is hard to justify tourism . We have to question our use of cruising or flights in our tourism consumption," she says.

We need to create a cultural shift that sees tourism consumption as a luxury to be savored and not something we can have every year or multiple times a year, like many have come to expect in the Global North. Shifting to an appreciation of local leisure and domestic travels and lower expectations of long-haul international travel is a must.

The Global North, i.e., the northern hemisphere, is responsible for 92% of global emissions.

Dr. Higgins-Desbiolles outlines how tourism is contributing to the depletion of natural resources, pollution, over-consumption and environmental destruction.

Part 1

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 9:14am

Air pollution linked to nearly 2,000 child deaths a day: Report

Nearly 2,000 children die every day from health problems linked to air pollution, which is now the second biggest risk factor for early death worldwide, a report said recently.

Exposure to air pollution contributed to the deaths of 8.1 million people—around 12 percent of all fatalities—in 2021, according to the report from the US-based Health Effects Institute.

This means air pollution has overtaken tobacco use and poor diet to become the second leading risk factor for early death, behind only high blood pressure, it said.

Little kids are particularly vulnerable to air pollution, and the institute partnered with the UN Children's Fund UNICEF for its annual State of Global Air report.

Air pollution contributed to the deaths of more than 700,000 children under the age of five, the report found.

More than 500,000 of those deaths were attributed to cooking indoors using dirty fuels such as coal, wood or dung, mostly in Africa and Asia.

Nearly every person in the world breathes unhealthy levels of air pollution every day, the report found. Over 90 percent of the deaths were linked to tiny airborne pollutants called PM2.5, which measure 2.5 micrometres or less, it said. Inhaling PM2.5 has been found to increase the risk of lung cancer, heart disease, stroke, diabetes and a range of other health problems.

The report aimed to link the rates of such diseases with air pollution levels.

But despite the "pretty stark" figures, the report could still be underestimating air pollution's impact, according to experts.

It did not take into account, for instance, how air pollution could affect brain health, neurodegenerative diseases or what impact using solid fuels for heating could have.

The report also found that ozone pollution—which is expected to get worse as the world warms due to human-driven climate change—was linked to nearly 500,000 deaths in 2021.

Source: AFP and other news agencies

https://ceh.unicef.org/spotlight-risk/air-pollution

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 8:33am

New technology provides electrifying insights into how catalysts work at the atomic level

A team led by Lawrence Berkeley National Laboratory (Berkeley Lab) has invented a technique to study electrochemical processes at the atomic level with unprecedented resolution and used it to gain new insights into a popular catalyst material.

Electrochemical reactions—chemical transformations that are caused by or accompanied by the flow of electric currents—are the basis of batteries, fuel cells, electrolysis, and solar-powered fuel generation, among other technologies. They also drive biological processes such as photosynthesis and occur under the Earth's surface in the formation and breakdown of metal ores.

The scientists have developed a cell—a small enclosed chamber that can hold all the components of an electrochemical reaction—that can be paired with transmission electron microscopy (TEM) to generate precise views of a reaction at an atomic scale. Better yet, their device, which they call a polymer liquid cell (PLC), can be frozen to stop the reaction at specific timepoints, so scientists can observe composition changes at each stage of a reaction with other characterization tools.

In a paper appearing in Nature, the team describes their cell and a proof of principle investigation using it to study a copper catalyst that reduces carbon dioxide to generate fuels.

Haimei Zheng, Atomic dynamics of electrified solid–liquid interfaces in liquid-cell TEM, Nature (2024). DOI: 10.1038/s41586-024-07479-w. www.nature.com/articles/s41586-024-07479-w

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 8:26am

Researchers create new class of materials called 'glassy gels'

Researchers have created a new class of materials called "glassy gels" that are very hard and difficult to break despite containing more than 50% liquid. Coupled with the fact that glassy gels are simple to produce, the material holds promise for a variety of applications.

A paper describing this work, titled "Glassy Gels Toughened by Solvent," appears in the journal Nature.

Gels and glassy polymers are classes of materials that have historically been viewed as distinct from one another. Glassy polymers are hard, stiff and often brittle. They're used to make things like water bottles or airplane windows. Gels—such as contact lenses—contain liquid and are soft and stretchy.

Now researchers have created a class of materials that they've termed glassy gels, which are as hard as glassy polymers, but—if you apply enough force—can stretch up to five times their original length, rather than breaking.

What's more, once the material has been stretched, you can get it to return to its original shape by applying heat. In addition, the surface of the glassy gels is highly adhesive, which is unusual for hard materials.

A key thing that distinguishes glassy gels is that they are more than 50% liquid, which makes them more efficient conductors of electricity than common plastics that have comparable physical characteristics.

Considering the number of unique properties they possess, researchers are optimistic that these materials will be very useful.

Michael Dickey, Glassy gels toughened by solvent, Nature (2024). DOI: 10.1038/s41586-024-07564-0. www.nature.com/articles/s41586-024-07564-0

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 11:25am

Starlings found to expend 25% less energy in follower position compared to flying solo

A multidisciplinary, multi-institutional team of researchers  has found that starlings that fly in a follower position expend 25% less energy than when they fly solo. In their study, published in the Proceedings of the National Academy of Sciences, the group designed complex experiments to learn more about the amount of energy savings for birds following another bird in flight rather than going it alone.

Prior research and logic suggest that if a bird were to fly behind another bird, it would use less energy because there would be less wind resistance. But testing the idea has proven difficult. In this new effort, the research team designed and carried out what they describe as "difficult" experiments to test energy expenditure by birds in flight.

Sonja I. Friman et al, It pays to follow the leader: Metabolic cost of flight is lower for trailing birds in small groups, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2319971121

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