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Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 12:45pm

The Chemical Origins of Life

How did life get started on Earth? And how are we using what we know to look for it throughout the galaxy?

Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 11:20am

A scarf that speaks? Scientists develop message display fabric

At first glance, the fabric looks like a pretty if not especially original scarf, with turquoise, blue and orange stripes in an open weave. But this fabric can communicate.

It's wearable, foldable and washable, but it's also a fully functioning display—capable of flashing messages or images, or even being used with a keyboard.

it could revolutionize communication and "help individuals with voice, speech or language difficulties to express themselves to others".

Large-area display textiles integrated with functional systems, Nature (2021). DOI: 10.1038/s41586-021-03295-8 , dx.doi.org/10.1038/s41586-021-03295-8

https://techxplore.com/news/2021-03-scarf-scientists-message-fabric...

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Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 11:14am

Face masks are a ticking plastic timebomb

Recent studies estimate that we use an astounding 129 billion face masks globally every month—that is 3 million a minute. Most of them are disposable face masks made from plastic microfibers.

With increasing reports on inappropriate disposal of masks, it is urgent to recognize this potential environmental threat and prevent it from becoming the next plastic problem.

Disposable masks are plastic products, that cannot be readily biodegraded but may fragment into smaller plastic particles, namely micro- and nanoplastics that widespread in ecosystems.

The enormous production of disposable masks is on a similar scale as plastic bottles, which is estimated to be 43 billion per month. However, different from plastic bottles, (of which app. 25 pct. is recycled), there is no official guidance on mask recycle, making it more likely to be disposed of as solid waste

If not disposed of for recycling, like other plastic wastes, disposable masks can end up in the environment, freshwater systems, and oceans, where weathering can generate a large number of micro-sized particles (smaller than 5 mm) during a relatively short period (weeks) and further fragment into nanoplastics (smaller than 1 micrometer).

"A newer and bigger concern is that the masks are directly made from microsized plastic fibers (thickness of ~1 to 10 micrometers). When breaking down in the environment, the mask may release more micro-sized plastics, easier and faster than bulk plastics like plastic bags.

How can you solve it?

Researchers recommend these solutions:

1. Set up mask-only trash cans for collection and disposal
2. consider standardization, guidelines, and strict implementation of waste management for mask wastes
3. replace disposable masks with reusable face masks like cotton masks
4. consider development of biodegradable disposal masks.

Elvis Genbo Xu et al, Preventing masks from becoming the next plastic problem, Frontiers of Environmental Science & Engineering (2021). DOI: 10.1007/s11783-021-1413-7

https://phys.org/news/2021-03-masks-plastic-timebomb.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 11:02am

Bacteria know how to exploit quantum mechanics, study finds

Photosynthetic organisms harvest light from the sun to produce the energy they need to survive. A new paper published by University of Chicago researchers reveals their secret: exploiting quantum mechanics.

Before this study, the scientific community saw quantum signatures generated in biological systems and asked the question, were these results just a consequence of biology being built from molecules, or did they have a purpose?" said Greg Engel, Professor of Chemistry and senior author on the study. "This is the first time we are seeing biology actively exploiting quantum effects.

The scientists studied a type of microorganism called green sulfur bacteria. These bacteria need light to survive, but even small amounts of oxygen can damage their delicate photosynthetic equipment. So they must develop ways to minimize the damage when the bacterium does encounter oxygen.

To study this process, researchers tracked the movement of energy through a photosynthetic protein under different conditions—with oxygen around, and without.

They found that the bacterium uses a quantum mechanical effect called vibronic mixing to move energy between two different pathways, depending on whether or not there's oxygen around. Vibronic mixing involves vibrational and electronic characteristics in molecules coupling to one another. In essence, the vibrations mix so completely with the electronic states that their identities become inseparable. This bacterium uses this phenomenon to guide energy where it needs it to go.

If there's no oxygen around and the bacterium is safe, the bacterium uses vibronic mixing by matching the energy difference between two electronic states in an assembly of molecules and proteins called the FMO complex, with the energy of the vibration of a bacteriochlorophyll molecule. This encourages the energy to flow through the 'normal' pathway toward the photosynthetic reaction center, which is packed full of chlorophyll.

But if there is oxygen around, the organism has evolved to steer the energy through a less direct path where it can be quenched. (Quenching energy is similar to putting a palm on a vibrating guitar string to dissipate energy.) This way, the bacterium loses some energy but saves the entire system.

Jacob S. Higgins et al, Photosynthesis tunes quantum-mechanical mixing of electronic and vibrational states to steer exciton energy transfer, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2018240118

https://phys.org/news/2021-03-bacteria-exploit-quantum-mechanics.ht...

Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 10:55am

Scientists develop new magnetic nanomaterial for counterfeit money prevention

An international research team  has developed a new iron-cobalt-nickel nanocomposite with tunable magnetic properties. The nanocomposite could be used to protect money and securities from counterfeiting. 

The new iron-cobalt-nickel nanocomposite was obtained by chemical precipitation, followed by a reduction process.

The new composite was observed to possess high value of coercivity, which makes the technology applicable e.g. to magnetic rubbers and different magnetically coupled devices. Another potential application is protecting money and securities from counterfeiting.

Tien Hiep Nguyen et al, Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications, Nanomaterials (2021). DOI: 10.3390/nano11020341

https://phys.org/news/2021-03-scientists-magnetic-nanomaterial-coun...

Comment by Dr. Krishna Kumari Challa on March 11, 2021 at 6:16am

How trees secretly talk to each other

Comment by Dr. Krishna Kumari Challa on March 10, 2021 at 10:16am

Why sea slugs cut off their own heads Autotomy, the voluntary shedding of a body part, is common to distantly-related animals such as arthropods, gastropods, asteroids, amphibians, and lizards. Autotomy is generally followed by regeneration of shed terminal body parts, such as appendages or tails. A a new type of extreme autotomy ‘s reported recently. Two species of sea slug, Elysia marginata and Elysia atroviridis, decapitate themselves — only to regrow a new body from the severed head. Researchers were astonished to observe slugs in captivity cutting off their own heads after their bodies became infected with parasites. Within 3 weeks, the heads regenerate a whole, parasite-free body, though the bodies never grow back new heads. https://www.cell.com/current-biology/fulltext/S0960-9822(21)00047-6?utm_source=Nature+Briefing&utm_campaign=3d9abe9084-briefing-dy-20210309&utm_medium=email&utm_term=0_c9dfd39373-3d9abe9084-44672165

Comment by Dr. Krishna Kumari Challa on March 10, 2021 at 10:12am

Bacterial film separates water from oil

Researchers have demonstrated that a slimy, yet tough, type of biofilm that certain bacteria make for protection and to help them move around can also be used to separate water and oil. The material may be useful for applications such as cleaning contaminated waters.

They reported the findings of an experiment in which they used a material produced by the bacteria Gluconacetobacter hansenii as a filter to separate water from an oil mixture.

The biofilm the bacteria make and release into their environment is made of cellulose, which is the same material that gives plants a sturdy structure in their cell walls. However, when bacteria make cellulose, it has a tightly packed, crystalline structure. It's one of the purest, if not the purest, forms of cellulose out there. The bacteria make the film to protect themselves.

The material was effective at removing water, and it 's sturdy. The oil doesn't want to go through the membrane; it has a repulsive effect to it. It's super fat-hating.

Researchers see a variety of potential applications for the material in situations where you need to recover water from an oily mixture—whether it be to clean water contaminated with a textile dye or for environmental remediation.

Zahra Ashrafi et al. Bacterial Superoleophobic Fibrous Matrices: A Naturally Occurring Liquid-Infused System for Oil–Water Separation, Langmuir (2021). DOI: 10.1021/acs.langmuir.0c02717

https://phys.org/news/2021-03-bacterial-oil.html?utm_source=nwlette...

Comment by Dr. Krishna Kumari Challa on March 10, 2021 at 10:03am

Humidity in breath makes cotton masks more effective at slowing the spread of COVID-19

Researchers have come up with a better way to test which fabrics work best for masks that are meant to slow the spread of COVID-19. By testing those fabrics under conditions that mimic the humidity of a person's breath, the researchers have obtained measurements that more accurately reflect how the fabrics perform when worn by a living, breathing person.

The new measurements show that under humid conditions, the filtration efficiency—a measure of how well a material captures particles—increased by an average of 33% in cotton fabrics. Synthetic fabrics performed poorly relative to cotton, and their performance did not improve with humidity. The material from medical-procedure masks also did not improve with humidity, though it performed in roughly the same range as cottons.

The filtration efficiency of cotton fabrics increases in humid conditions because cotton is hydrophilic, meaning it likes water. By absorbing small amounts of the water in a person's breath, cotton fibers create a moist environment inside the fabric. As microscopic particles pass through, they absorb some of this moisture and grow larger, which makes them more likely to get trapped.

Most synthetic fabrics, on the other hand, are hydrophobic, meaning they dislike water. These fabrics do not absorb moisture, and their filtration efficiency does not change in humid conditions.

Christopher D. Zangmeister et al, Hydration of Hydrophilic Cloth Face Masks Enhances the Filtration of Nanoparticles, ACS Applied Nano Materials (2021). DOI: 10.1021/acsanm.0c03319

https://phys.org/news/2021-03-humidity-cotton-masks-effective-covid...

Comment by Dr. Krishna Kumari Challa on March 10, 2021 at 8:18am

How to cut onions without crying using science

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