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Comment by Dr. Krishna Kumari Challa on November 18, 2023 at 7:47am

A Virus that Generates Electricity 

Melting a bacteriophage’s coat of proteins turns it into a tiny power plant, which could fire up the discovery of new bioengineered devices.

Our bodies are alive with electrical signals that allow us to contract muscles and sense the world. The complex brain orchestrates these processes, but it turns out that even simpler biological entities generate electricity. In a new study published in Advanced Materials, researchers reported that a bioengineered virus generated electricity when exposed to heat, a phenomenon known as pyroelectricity. By working with viruses, the researchers hope to better understand bioelectricity in the human body and apply this knowledge to power novel biomaterials.

The M13 bacteriophage, a rod-shaped virus that infects bacteria, is adorned in a molecular coat, woven from nearly 3,000 copies of a helical protein. The protein is positively charged on the inside and negatively charged on the outside, but the arrangement of the thick protein coat balances out the charges. 

Over a decade ago, a research team put the squeeze on the coat proteins, which caused the bacteriophage to exhibit piezoelectricity—the ability to transform mechanical force into electricity.  When the researchers applied pressure to the viruses, the coat proteins changed shape, breaking the charge symmetry and becoming polarized, which generated an electric field and induced a current.

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Comment by Dr. Krishna Kumari Challa on November 18, 2023 at 7:33am

What happens when AI eats itself?

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 12:29pm

Light, not just heat, might spur water to evaporate

If real, the effect might be occurring naturally all over the world

Green light means “go.” That might apply to evaporating water molecules too.

Visible light, especially that of a greenish hue, might spur water to evaporate, researchers report in the Nov. 7 Proceedings of the National Academy of Sciences. In experiments, water evaporating under visible light showed a higher evaporation rate than possible based on heat alone.

Coupled with other observations, they say, the finding suggests that when light shines on water, individual particles of light, or photons, can sever the bonds that connect water molecules, releasing clusters of molecules into the air.

In the new study, the researchers shone light on water contained in porous hydrogels, materials that greedily sop up water. The proposed effect occurs where air meets water, and the hydrogels the researchers studied contain innumerable crannies where the two meet, allowing the water to be cleaved off and escape. In some cases, the evaporation rate was more than double the expectation based on heat. What’s more, the evaporation rate varied with the wavelength of the light. Green light produced the highest evaporation rate.

Y. Tu et al. Plausible photomolecular effect leading to water evaporation exceed.... Proceedings of the National Academy of Sciences. Vol. 120, November 7, 2023, e2312751120. doi: 10.1073/pnas.2312751120.

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 11:27am

They used social marketing—a process that focuses on changing behavior to improve health using strategies from the commercial marketing world—to create a faster, more cost-effective plan to directly educate the people responsible for the manufacturing and repairing of the pumps.

The researchers worked with local staff to build the capacity and skill set of technicians, while overseeing and facilitating work on the pumps to ensure they understood how to remove and replace the leaded pump components. Additionally, to understand the impact of this intervention, they worked with local health practitioners to measure blood lead levels of small children who drank water from the pumps before and after the leaded pump components were replaced.

Of the 55 children tested, 87 percent experienced a significant decrease in blood lead levels once leaded components were removed from the pumps.

Adaline M. Buerck et al, Reductions in Children's Blood Lead Levels from a Drinking-Water Intervention in Madagascar, Sub-Saharan Africa, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c03774

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Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 11:25am

Researchers help reduce lead levels in Madagascar drinking water

A team of engineers and public health experts helped residents reduce their exposure to lead—a major global environmental pollutant that causes more than 1 million premature deaths each year. By combining efforts to replace water pumps and educate city technicians, these researchers helped decrease the blood lead levels of 87 percent of the children tested during their study.

The lead concentrations of the water from the pumps exceeded the World Health Organization's recommended limit of lead in drinking water—10 micrograms per liter. In some cases, the water contained more than 10 times the recommended limit.

The families and children are drinking this water and using it to cook their meals.

In low- and middle-income countries, there is a lack of regulations and understandings of the harmful effects of lead, as well as other comorbidities, such as improper nutrition, that can increase childhood lead absorption.

The pumps are the primary source of water for more than three-quarters of the coastal area of Madagascar, where there are about 9,000 pumps because tap water is not always affordable or available for the city's 280,000 people. 

Part 1

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 10:47am

How cell identity is preserved when cells divide

Every cell in the human body contains the same genetic instructions, encoded in its DNA. However, out of about 30,000 genes, each cell expresses only those genes that it needs to become a nerve cell, immune cell, or any of the other hundreds of cell types in the body.

Each cell's fate is largely determined by chemical modifications to the proteins that decorate its DNA; these modification in turn control which genes get turned on or off. When cells copy their DNA to divide, however, they lose half of these modifications, leaving the question: How do cells maintain the memory of what kind of cell they are supposed to be?

A new MIT study proposes a theoretical model that helps explain how these memories are passed from generation to generation when cells divide. The research team suggests that within each cell's nucleus, the 3D folding pattern of its genome determines which parts of the genome will be marked by these chemical modifications.

After a cell copies its DNA, the marks are partially lost, but the 3D folding allows each daughter cell to easily restore the chemical marks needed to maintain its identity. And each time a cell divides, chemical marks allow a cell to restore its 3D folding of its genome. This way, by juggling the memory between 3D folding and the marks, the memory can be preserved over hundreds of cell divisions.

 Jeremy A. Owen et al, Design principles of 3D epigenetic memory systems, Science (2023). DOI: 10.1126/science.adg3053. www.science.org/doi/10.1126/science.adg3053

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 10:32am

Bear genes show circadian rhythms even during hibernation

The internal clocks of grizzly bears appear to keep ticking through hibernation, according to a genetic study. This persistence highlights the strong role of circadian rhythms in the metabolism of many organisms including humans.

The genetic study confirmed observational evidence that bears' energy production still waxes and wanes in a daily pattern even as they slumber for several months without eating. The researchers also found that during hibernation the amplitude of the energy production was blunted, meaning the range of highs and lows was reduced. The peak also occurred later in the day under hibernation than during the active season, but the daily fluctuation was still there.  

This underscores the importance of the circadian rhythms themselves—that they give organisms the flexibility to still function in a state as extreme as a hibernating bear.

Other research has shown that circadian rhythms, the 24-hour physical cycles common to most living animals on Earth, have ties to metabolic health. In humans, major disruptions to these patterns, such as occur in night shift work, have been linked to metabolic problems like weight gain and higher prevalence of diabetes.

Ellery P. Vincent et al, Circadian gene transcription plays a role in cellular metabolism in hibernating brown bears, Ursus arctos, Journal of Comparative Physiology B (2023). DOI: 10.1007/s00360-023-01513-5

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 10:06am

One of the reasons ECT isn't more popular is that for a lot of people, it's easier and more convenient to just take a pill. However, in people for whom medications don't work, electroconvulsive therapy can be life-saving. Understanding how it works will help us discover ways to increase the benefits while minimizing side effects.

The researchers used electroencephalography (EEG) scans to study the brain activity of patients who received ECT therapy for depression. They also looked at another similar form of treatment called magnetic seizure therapy, which induces a seizure with magnets instead of electrodes. Both therapies showed increased aperiodic activity levels in patients' brains post-treatment.

One of the functions of aperiodic activity in the brain is helping control how neurons turn on and off. Our neurons are constantly going through cycles of excitation and inhibition that correspond with different mental states. Aperiodic activity helps boost inhibitory activity in the brain, effectively slowing it down.

Something we see regularly in the EEG scans of people who receive electroconvulsive or magnetic seizure therapy is a slowing pattern in the brain's electrical activity. This pattern has gone unexplained for many years, but accounting for the inhibitory effects of aperiodic activity helps explain it. It also suggests that these two forms of therapy are causing similar effects in the brain.

 Translational Psychiatry (2023). doi.org/10.1038/s41398-023-02631-y

Translational Psychiatry (2023). doi.org/10.1038/s41398-023-02634-9

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Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 10:04am

New studies of brain activity explain benefits of electroconvulsive therapy

Electroconvulsive therapy (ECT), formerly known as electroshock therapy, involves inducing a brief seizure in the brain using controlled doses of electricity. While ECT is highly effective for certain mental illnesses, particularly depression, the reasons for its efficacy have long puzzled the fields of psychiatry and neuroscience.

Now, researchers  may have an answer. In two new studies published in Translational Psychiatry, they propose a new hypothesis that ECT alleviates depression symptoms by increasing aperiodic activity, a type of electrical activity in the brain that doesn't follow a consistent pattern and is generally considered to be the brain's background noise.

Electroconvulsive therapy has a great track record, but a bad reputation. The therapy is effective in up to 80% of patients who receive the treatment, most often for depression but occasionally for bipolar disorder or schizophrenia. However, despite this high success rate, electroconvulsive therapy is frequently associated with frightening images of people receiving painful, high voltage shocks.

A lot of people are surprised to learn that doctors still use electroconvulsive therapy, but the modern procedure uses highly controlled dosages of electricity and is done under anesthesia. It really doesn't look like what you see in movies or television.

While generally safe and effective, ECT does have drawbacks, including temporary confusion and cognitive impairment. It also requires multiple outpatient visits, which can present a barrier to some people who might otherwise benefit from the treatment.

Part 1

Comment by Dr. Krishna Kumari Challa on November 17, 2023 at 9:56am

1.3 million lives lost every year in just seven countries: The devastating impact of tobacco revealed

Every year 1.3 million lives are lost to cancers caused by smoking tobacco across the UK, US and BRICS nations (Brazil, Russia, India, China and South Africa), according to a new study.

Researchers have found that together, the seven countries represented more than half of the global burden of cancer deaths every year. They concluded that smoking, as well as three other preventable risk factors—alcohol, overweight or obesity, and human papillomavirus (HPV) infections—caused almost 2 million deaths combined.

Researchers concluded that the four preventable risk factors resulted in over 30 million years of life lost each year. Smoking tobacco had by far the biggest impact—leading to 20.8 million years of life being lost, the study said.

Some of the other key findings from the study include:

• Preventable risk factors were associated with different cancer types in different places. For example, in India, there were more premature deaths from head and neck cancer in men, and gynecological cancer in women, but in every other country, tobacco smoking caused the most years of life to be lost to lung cancer.

• Researchers believe that this is due to differences in each of the countries—cervical screening is less comprehensive in India and South Africa than in other countries like the UK and US, which would explain why there are more premature deaths from gynecological cancers due to HPV infection in India and South Africa. The higher number of years of life lost to head and neck cancer in men in India could be explained by smoking habits being different to those in the UK, with the general population smoking different tobacco products.

• There are gender differences in the number of cancer deaths and years of life lost to different risk factors. Men have higher rates of years of life lost to smoking and drinking alcohol, because smoking and drinking rates tend to be higher in men. In China, India and Russia, rates of years of life lost to tobacco smoking and alcohol were up to nine times higher in men than women.

• Meanwhile, being overweight or obese, and HPV infection, led to more cancer deaths and years of life lost in women than in men. In South Africa and India, HPV led to particularly high rates of years of life lost with a large gender imbalance. Rates were 60 times higher in women than men in South Africa, and 11 times higher in India, which highlights the urgent need for improved access to cervical screening and the HPV vaccination in these countries.

• The differences in cancers linked to HPV infection are stark—mortality rates are six times higher in South Africa than in the UK and US. Cervical cancer has been largely prevented by screening in the UK and US, and is on track to be almost eliminated through HPV vaccination in the UK.

International burden of cancer deaths and years of life lost from cancer attributable to four major risk factors: a population-based study in Brazil, Russia, India, China, South Africa, the United Kingdom, and United States, eClinicalMedicine (2023).

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