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Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 7:28am

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 11:32am

Technology enables conversion of mobile phone cameras into high-resolution microscopes

Researchers have developed the world's smallest LED (light-emitting diode) that enables the conversion of existing mobile phone cameras into high-resolution microscopes. Smaller than the wavelength of light, the new LED was used to build the world's smallest holographic microscope, paving the way for existing cameras in everyday devices such as mobile phones to be converted into microscopes via only modifications to the silicon chip and software. This technology also represents a significant step forward in the miniaturization of diagnostics for indoor farmers and sustainable agriculture.

This breakthrough was supplemented by the researchers' development of a revolutionary neural networking algorithm that is able to reconstruct objects measured by the holographic microscope, thus enabling enhanced examination of microscopic objects such as cells and bacteria without the need for bulky conventional microscopes or additional optics. The research also paves the way for a major advancement in photonics—the building of a powerful on-chip emitter that is smaller than a micrometer, which has long been a challenge in the field.

Zheng Li et al, A sub-wavelength Si LED integrated in a CMOS platform, Nature Communications (2023). DOI: 10.1038/s41467-023-36639-1

Iksung Kang et al, Simultaneous spectral recovery and CMOS micro-LED holography with an untrained deep neural network, Optica (2022). DOI: 10.1364/OPTICA.470712

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:27am

Deep sleep may mitigate Alzheimer's memory loss, research shows

As the most prevalent form of dementia, Alzheimer's disease destroys memory pathways and, in advanced forms, interferes with a person's ability to perform basic daily tasks. Roughly one in nine people over age 65 have the progressive disease—a proportion that is expected to grow rapidly as the baby boomer generation ages.

In recent years, scientists have probed the ways that deposits of beta-amyloid associate with Alzheimer's disease and how such deposits also affect memory more generally. In addition to sleep being a foundational part of memory retention, the team at UC Berkeley previously discovered that the declining amount of a person's deep sleep could act as a 'crystal ball' to forecast a faster rate of future beta-amyloid buildup in the brain, after which dementia is more likely set in.

A deep slumber might help buffer against memory loss for older adults facing a heightened burden of Alzheimer's disease, new research suggests.

Deep sleep, also known as non-REM slow-wave sleep, can act as a "cognitive reserve factor" that may increase resilience against a protein in the brain called beta-amyloid that is linked to memory loss caused by dementia. Disrupted sleep has previously been associated with faster accumulation of beta-amyloid protein in the brain. However, the new research  reveals that superior amounts of deep, slow-wave sleep can act as a protective factor against memory decline in those with existing high amounts of Alzheimer's disease pathology—a potentially significant advance that experts say could help alleviate some of dementia's most devastating outcomes.

Zsófia Zavecz et al, NREM sleep as a novel protective cognitive reserve factor in the face of Alzheimer's disease pathology, BMC Medicine (2023). DOI: 10.1186/s12916-023-02811-z

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:19am

Study finds doctors prescribing untested drug combinations with high addiction potential

The Center for Drug Safety and Effectiveness at Johns Hopkins University has led a study into prescription drug use of multiple concurrent central nervous system (CNS)-active drugs. They found widespread combination prescribing of drugs classified as Schedule II controlled substances with a high potential for psychological or physical dependence and with limited combined clinical trial testing.

The paper, "Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis," published in BMJ Open, examined patterns of medical amphetamine and methylphenidate stimulant drug use, both substances considered to have a high potential for psychological or physical addiction.

Utilizing prescription drug claims for US adults aged 19 to 64 from a commercial insurance claims database with over 9.1 million continuously enrolled adults, stimulant use was defined as adults filling one or more stimulant prescriptions in a single year.

The study identified 276,223 individuals (3.0%) using Schedule II stimulants in 2020. They filled a median of eight prescriptions that provided 227 days of exposure. Among this group, 125,781 (45.5%) combined use of one or more additional CNS active drugs for a median of 213 days. Also, 66,996 (24.3%) stimulant users used two or more additional CNS-active medications for a median of 182  days. Among stimulants users, 131,485 (47.6%) used an antidepressant, 85,166 (30.8%) filled prescriptions for anxiety/sedative/hypnotic medications and 54,035 (19.6%) received opioid prescriptions.

Many adults using Schedule II stimulants simultaneously use one or more additional CNS-active drugs. As these can have tolerance and withdrawal effects or potential recreational abuse, the authors suggest that "discontinuation may be challenging," which is another way of stating that these individuals have likely formed a habitual dependence or addiction possibly requiring intervention or rehabilitation.

Once treatment has started, 75% of patients become long-term users. This underscores the possible risks of non-medical guideline use, noting the issues that warranted the classification of these drugs as having a high potential for psychological or physical dependence and their prominent appearance in toxicology drug rankings of fatal overdose cases.

 Thomas J Moore et al, Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis, BMJ Open (2023). DOI: 10.1136/bmjopen-2022-069668

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:02am

Their genetic background—meaning the unique features in the B chromosome flies' genetic make-up—supports their preferential transmission to the next generation. That buys these  evolutionary time to become a new chromosome, whether that's picking up an essential gene or acquiring something that enables them to better cheat.

Importantly, meiotic drive is a powerful force that can shape how genomes evolve. 

Researchers are also examining how specific mutations can lead to chromosome breakage and new chromosome formation, revealing the mechanism of how supernumeraries arise and become requisite components of a genome.

Stacey L. Hanlon et al, B chromosomes reveal a female meiotic drive suppression system in Drosophila melanogaster, Current Biology (2023). DOI: 10.1016/j.cub.2023.04.028

Part 2

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:00am

Scientists discover the dynamics of an 'extra' chromosome in fruit flies

Most chromosomes have been around for millions of years. Now, researchers  have revealed the dynamics of a new, very young chromosome in fruit flies that is similar to chromosomes that arise in humans and is associated with treatment-resistant cancer and infertility. The findings may one day lead to developing more targeted therapies for treating these conditions.

A new study published in Current Biology on May 4, 2023, reveals how this small chromosome that arose less than 20 years ago has persisted in a single, lab-reared strain of the fruit fly, Drosophila melanogaster, and is correlated with supernumerary (extra) chromosomes in humans.

Supernumerary chromosomes in humans are found in cancer cells and frequently interfere with drugs designed to target tumors, making these types of cancers, like osteosarcoma, difficult to treat. In addition, the presence of supernumerary chromosomes in men can disrupt normal chromosome segregation during sperm production, which can cause infertility.

Being able to understand how supernumerary chromosomes arise and what their structures are can potentially illuminate their vulnerabilities. This may enable the development of potential therapeutic targets.

Called B chromosomes—as opposed to the standard "A" set of essential chromosomes—these genetic elements naturally appeared in a single laboratory stock of fruit flies.

Now, the researchers are witnessing chromosome birth and evolution in less than two decades.

How does something like this new chromosome apparently arise from nothing? More important, as these newly born B chromosomes do not possess any known essential genes for fruit fly function, how do they persist in a genome? In short, by cheating. They do not follow the rules.

Researchers discovered that the fruit fly B chromosomes are maintained by a mechanism called "meiotic drive" that enables the them to rebel against the usual rules of inheritance. The B chromosomes drive their way into the next generation during the formation of the egg to ensure their own persistence in more than half of the next generation.

Part 1

Comment by Dr. Krishna Kumari Challa on May 4, 2023 at 11:04am

Birds of a Feather Video-Flock Together: Design and Evaluation of an Agency-Based Parrot-to-Parrot...

Comment by Dr. Krishna Kumari Challa on May 4, 2023 at 10:24am

'Gluing' soft materials without glue!

You're likely familiar with the messy, sticky, frustration-inducing nature of liquid glues. But researchers reporting in ACS Applied Materials & Interfaces now have a brand-new way to weld squishy stuff together without the need for glue at all. They've demonstrated a universal, "electroadhesion" technique that can adhere soft materials to each other just by running electricity through them.

Electroadhesion, in which an electric field is used to hold oppositely charged materials together, forming attachments between the materials' components. This can involve chemical bonds, like ionic bonds, or more physical connections, like ensnaring polymer chains together. Plus, it works with little more than a household battery and pencil lead..

To explore the phenomenon, the team tested a gel in addition to three types of capsules made of alginate or chitosan—both naturally occurring polymers—that were either positively or negatively charged. When attached to graphite electrodes and exposed to a 10-V electric field for around 10 seconds, the oppositely charged materials stuck together.

This bond was strong enough to withstand gravity, and evidence from previous experiments suggests it could last for years. By reversing the flow of electricity, however, the bond was easily broken. .

The researchers also used electroadhesion to sort capsules by their charges, either by laying a charged gel on top of several capsules, or by touching them with a fingertip "robot" that adhered the capsules to themselves. The researchers say that this work demonstrates the universality of electroadhesion and could one day be used in robotics and tissue engineering.

 Leah K. Borden et al, Universal Way to "Glue" Capsules and Gels into 3D Structures by Electroadhesion, ACS Applied Materials & Interfaces (2023). DOI: 10.1021/acsami.2c20793

Comment by Dr. Krishna Kumari Challa on May 4, 2023 at 10:09am

Although India has made major progress in reducing child mortality, diarrhea—caused mostly by contaminated water and food—remains a leading killer.

More than 55,000 children under five died of diarrhea across India in 2019, according to a study published last year in the scientific journal BMC Public Health.

The Yamuna in Delhi is one of the world's filthiest rivers and is considered ecologically dead in places, although people still wash clothes and take ritual baths in it.

It often billows with white foam, and facilities processing drinking water from the river for Delhi's 20 million people regularly shut down because of dangerous ammonia levels.

Despite some bright spots, as well as efforts to plant more trees alongside rivers, the situation elsewhere is often no better in big cities including Mumbai and Chennai.

In Bengaluru, massive Bellandur Lake has on occasion caught fire when methane, generated by bacteria feasting on sewage in the oxygen-depleted water, ignited.

According to the World Bank, India is one of the most "water-stressed" countries in the world, with plummeting water tables and increasingly erratic monsoon rains. India is headed for a water crisis. Sewage can so easily be co-opted to fight that and help us to a very large extent solve the problem in our cities.

India's water is so seasonal. Many cities in India get 50 rain days... but sewage is available every day because you go to the bathroom every day... It's such a powerful weapon.

Children keep falling sick... If they don't get treatment and medicine, the children will die.

Source: 2023 AFP

https://phys.org/news/2023-05-dead-rivers-flaming-lakes-india.html?...

Part 2

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Comment by Dr. Krishna Kumari Challa on May 4, 2023 at 10:07am

Dead rivers, flaming lakes: India's sewage failure

India at the end of April was projected to have overtaken China as the world's most populous country, according to the United Nations, with almost 1.43 billion people.

Its urban population is predicted to explode in the coming decades, with over 270 million more people forecast to live in its cities by 2040.

But of the 72 billion liters of sewage currently generated in urban centers every day, 45 billion liters—enough to fill 18,000 Olympic-sized swimming pools—aren't treated, according to government figures for 2020-21.

India's sewerage system does not connect to about two-thirds of its urban homes, according to the National Faecal Sludge and Septage Management Alliance (NFSSM).

Many of the sewage treatment plants in operation don't comply with standards— according to media reports.

Coupled with huge volumes of industrial effluent, the sewage is causing disease, polluting India's waterways, killing wildlife and seeping into groundwater.

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