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Comment by Dr. Krishna Kumari Challa 14 hours ago

Modern pesticides damage the brain of bees so they can't move in a straight line

The challenge to let people walk back and forth in a straight line isn't just used by police to test if drivers are intoxicated: it's also used by neurologists to diagnose neurological disorders like ataxia, where parts of the brain that coordinate movement are impaired. Now, researchers use an insect version of this challenge to show for the first time that modern pesticides damage the nervous system of honeybees so that it becomes hard for them to walk in a straight line. The results are published in Frontiers in Insect Science.

The commonly used insecticides like sulfoxaflor and the neonicotinoid imidacloprid can profoundly impair the visually guided behavior of honeybees. New research results are reason for concern because the ability of bees to respond appropriately to visual information is crucial for their flight and navigation, and thus their survival.

The results add to what the Food and Agriculture Organization of the United Nations and the World Health Organization have called the "rapidly growing body of evidence [which] strongly suggests that the existing levels of environmental contamination [from neonicotinoid pesticides] are causing large-scale adverse effects on bees and other beneficial insects."

The researchers also show with molecular techniques that pesticide-exposed bees tended to have elevated proportion of dead cells in parts of the brain's optic lobes, important for processing visual input. Likewise, key genes for detoxification were dysregulated after exposure.

Rachel H. Parkinson et al, Honeybee optomotor behaviour is impaired by chronic exposure to insecticides, Frontiers in Insect Science (2022). DOI: 10.3389/finsc.2022.936826

Comment by Dr. Krishna Kumari Challa 14 hours ago

Adults who, as children, had half their brain removed still able to score well with face and word recognition

A team of researchers at Carnegie Mellon University's Department of Psychology and Neuroscience Institute has found that adults who had a hemispherectomy as a child scored surprisingly well on face and word recognition tests. Their paper is posted on the bioRxiv preprint server. In epilepsy, abnormal brain activity results in chronic seizures. Some people respond well to medication and others due not; for example, some people experience seizures so often that they become incapacitating. Some young patients in these circumstances are given the option of undergoing a hemispherectomy, the complete removal of the left or right hemisphere of the brain. Prior research has shown that these procedures, when done at a very young age, allow most patients to retain their IQ and their ability to communicate and live relatively normal lives. In sharp contrast, damage to either hemisphere, much less removal of one or the other in adults, leads to severe symptoms or death. In this new effort, the researchers sought to learn more about the cognitive abilities of adults who had undergone a hemispherectomy. Forty subjects were shown grayscale pictures of human faces without hair for 750 milliseconds, followed by a pause of 150 milliseconds. Then another face was shown for 150 milliseconds after which the volunteer reported whether it was the same face or not. The whole process was then repeated several times with different faces. The researchers then repeated the entire exercise but used simple, four-letter words. The researchers expected that those volunteers who had only their right hemisphere would do well at face recognition but not as well at word recognition, since the right hemisphere is generally used to process images while the left hemisphere processes words; they expected the opposite results for those who still had just their left hemisphere. Instead, the researchers found that both groups performed nearly equally well and both were on average 86% accurate on the tests compared to a control group consisting of people who had not undergone an hemispherectomy, with average 96% accuracy. The researchers also conducted a nearly identical experiment in which the faces and words were shown off to the left or right; both groups still did surprisingly well—but there was one interesting difference. In comparing their results with the control group, those who had undergone a hemispherectomy did as well as the control group in identifying images or words in two instances—when a word was placed on the left side, or a face on the right.

Michael C. Granovetter et al, With Childhood Hemispherectomy, One Hemisphere Can Support—But is Suboptimal for—Word and Face Recognition (2020). DOI: 10.1101/2020.11.06.371823

Comment by Dr. Krishna Kumari Challa 15 hours ago

Pre-fertilization DNA transfer to avoid mitochondrial disease inheritance appears safe

Transferring the nuclear genome from one egg into the cytoplasm of a donor egg is a strategy to enable women carrying mutations in their mitochondrial DNA to have healthy babies. A new study  published August 16 in the open-access journal PLOS Biology, uses multiple "omics" techniques to show that this strategy, called spindle transfer, is likely to be safe, with little evidence of genetic or functional difference between the resulting embryos and healthy control in vitro fertilization (IVF) embryos. The results are likely to spur further adoption of spindle transfer for IVF when there is a risk of mitochondrial disease.

Mitochondria, the energy powerhouses of the cell, contain their own DNA, mutations in which can cause a variety of inherited diseases, including metabolic, muscular, and neurologic disorders. In human reproduction, only maternal mitochondria, contained in the egg, are inherited. To interrupt that inheritance, techniques have been developed to place parental nuclear DNA into cytoplasm from donor cells carrying healthy mitochondria, either just before fertilization (spindle transfer), or just after (pronuclear transfer).

The "spindle" refers to the division apparatus that holds the nuclear chromosomes in suspension until fertilization. During spindle transfer, the maternal spindle is removed from an unfertilized egg and placed into a donor egg that has had its own spindle removed. (Pronuclear transfer removes the pronucleus, containing both egg and sperm DNA, and places it in a donor embryo whose pronucleus has been removed.) Spindle transfer has been used clinically, but there remain questions about its safety.

To shed light on this question, the authors performed three different types of analyses on single cells from 23 blastocysts following spindle transfer and compared them to 23 control IVF blastocysts. (The blastocyst is the multicellular ball that forms about 5 or 6 days after fertilization, ready for implantation into the uterine wall.) They found no difference in DNA copy number, a measure of genomic integrity, between spindle transfer and control blastocysts. RNA expression profiles were also similar between the two blastocyst types, regardless of which layer of the blastocyst the cells were taken from.

The authors did find a small but significant reduction in the level of DNA demethylation in spindle transfer blastocysts in one layer, the trophectoderm, though not in two other layers. DNA demethylation is one of the processes used to increase gene expression during development, and their analysis suggested that the reduction was evidence of a slight delay in the process, rather than a permanent inability to upregulate the affected genes. It is quite possible that after the blastocyst stage, the spindle transfer embryos can catch up to complete DNA demethylation before implantation.

The researchers concluded that the spindle transfer seems generally safe and does not severely disturb embryonic development. However, given the limitation of the study, more dimensions and larger-scale evaluations are still needed to determine whether this technique can be applied to a wider set of clinical trials.

Single-cell multiomics analyses of spindle-transferred human embryos suggest a mostly normal embryonic development, PLoS Biology (2022). DOI: 10.1371/journal.pbio.3001741

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Comment by Dr. Krishna Kumari Challa 15 hours ago

Young mice transfused with blood from old mice became fatigued faster and ran shorter distances

A team of researchers from Korea University College of Medicine, the University of California and the Buck Institute for Research on Aging reports that transfusing young mice with blood from older mice makes them grow fatigued and unable to run long distances. The study is published in the journal Nature Metabolism. In 2005, a team of researchers at the University of California stitched pairs of old/young mice together to learn more about the aging process—in that effort, the mice were conjoined; they shared not only blood, but some organs. Testing of the older mice showed that the infusion of younger blood resulted in the reversal of some signs of aging. In this new effort, the researchers tested the process in reverse without resorting to conjoining. The work involved transfusing blood from an aged, two-year-old mouse into mice that were just three months old every day for a week, and then studying the young mice to measure the impact. Putting the mice on a treadmill and getting them to run showed that the young mice became fatigued faster and were not able to run as far as a control group (young mice transfused with blood from other young mice.) The young mice transfused with the blood of older mice showed markers for aging of the liver and kidney damage. The researchers also ran the experiment in reverse, giving old mice young blood, which resulted in reductions in fibrosis and lipids—and also fatigue. There was also an increase in endurance. The researchers suggest that it is likely that cells in the blood of older mice held a senescence-associated secretory phenotype, leading to muscle weakness, tissue damage and other signs of aging in the transfused younger mice. They suggest it also seems possible that cells in the blood from the older mice had ceased reproducing and were having an impact on the younger cells. The researchers also took an indirect approach to testing whether similar results might be observed in humans—they placed cells taken from an older person into plasma from a younger person. Six days later, they found biomarkers of aging.

Ok Hee Jeon et al, Systemic induction of senescence in young mice after single heterochronic blood exchange, Nature Metabolism (2022). DOI: 10.1038/s42255-022-00609-6

Comment by Dr. Krishna Kumari Challa 15 hours ago

The entanglement of two quantum memory systems 12.5 km apart from each other

Quantum computing technology could have notable advantages over classical computing technology, including a faster speed and the ability to tackle more complex problems. In recent years, some researchers have also been exploring the possible establishment of a "quantum internet," a network that would allow quantum devices to exchange information, just like classical computing devices exchange information today.

The quantum internet could open fascinating possibilities for numerous quantum technology applications. For instance, it could enable more secure communications, more precise remote sensing and distributed quantum computing networks.

Researchers at the University of Science and Technology of China and Jinan Institute of Quantum Technology have recently demonstrated quantum entanglement  between two memory devices located at 12.5 km apart from each other within an urban environment. Their paper, published in Physical Review Letters, could be a further step towards the development of a quantum internet.

In their experiment, researchers  introduced two quantum nodes in different locations in an urban environment, placing them at a 12.5 km distance from one another. In the first node, dubbed node A, they entangled their first quantum memory with a single photon. This single photon was then sent to node B and stored within the second quantum memory.

In this way they entangled the two remote quantum memories.

Xi-Yu Luo et al, Postselected Entanglement between Two Atomic Ensembles Separated by 12.5 km, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.050503

Yong Yu et al, Entanglement of two quantum memories via fibres over dozens of kilometres, Nature (2020). DOI: 10.1038/s41586-020-1976-7

Comment by Dr. Krishna Kumari Challa yesterday

Potential anti-aging components of Moringa oleifera leaf

Moringa oleifera Lam., also known as drum stick and Miracle Tree, primarily derived from India, is now widely distributed in tropical and subtropical regions. Previous studies have showed that M. oleifera has anti-aging effects, but there is a lack of in-depth research on the specific active ingredients and mechanisms of this anti-aging activity. Researchers are working to screen out the most effective active components of M. oleifera leaves.

Scientists in China conducted in vitro elastase and collagenase enzyme inhibitory assays to evaluate the activities of M. oleifera leaf extracts.

They found that M. oleifera leaf extracts possessed promising anti-elastase and anti-collagenase activities. Then, 10, 8, and 14 potential bioactive phytochemicals were screened out from M. oleifera leaf extracts against elastase, collagenase and hyaluronidase using the multi-target bio-affinity ultrafiltration coupled to high-performance liquid chromatography-mass spectrometry (AUF-HPLC-MS), respectively. In addition, further verification of representative active components was completed with molecular docking analysis. Results showed that these potentially active compounds could form hydrogen bonds with amino acid residues Asn112, Trp115, Glu141, Glu164, and Asp221 of elastase, Arg214, Val215, Glu219, and Pro238 of collagenase, Arg47, Asp56, Gly58, Asp111, Glu113, and Ser304 of hyaluronidase, respectively. These hydrogen bonds enhanced the binding ability of active small molecules to biological target molecules. This is the first study to comprehensively demonstrate M. oleifera leaves possess the significant elastase and collagenase inhibitory activities in vitro and reveal its potential bioactive components as well as the mechanism of anti-aging activity.

This work provides a theoretical basis for its further development into functional anti-aging products in the cosmetics and cosmeceutical industries combating aging and skin wrinkling.

Yongbing Xu et al, Potential Anti-aging Components From Moringa oleifera Leaves Explored by Affinity Ultrafiltration With Multiple Drug Targets, Frontiers in Nutrition (2022). DOI: 10.3389/fnut.2022.854882

Comment by Dr. Krishna Kumari Challa yesterday

Nuclear war would cause a global famine and kill billions, study finds

More than 5 billion people would die of hunger following a full-scale nuclear war between the U.S. and Russia, according to a global study led by Rutgers climate scientists that estimates post-conflict crop production.

Building on past research, researchers now worked to calculate how much sun-blocking soot would enter the atmosphere from firestorms that would be ignited by the detonation of nuclear weapons. Researchers calculated soot dispersal from six war scenarios—five smaller India-Pakistan wars and a large U.S.-Russia war—based on the size of each country's nuclear arsenal.

These data then were entered into the Community Earth System Model, a climate forecasting tool supported by the National Center for Atmospheric Research (NCAR). The NCAR Community Land Model made it possible to estimate productivity of major crops (maize, rice, spring wheat and soybean) on a country-by-country basis. The researchers also examined projected changes to livestock pasture and in global marine fisheries.

Under even the smallest nuclear scenario, a localized war between India and Pakistan, global average caloric production decreased 7% within five years of the conflict. In the largest war scenario tested—a full-scale U.S.-Russia nuclear conflict—global average caloric production decreased by about 90% three to four years after the fighting.

Crop declines would be the most severe in the mid-high latitude nations, including major exporting countries such as Russia and the U.S., which could trigger export restrictions and cause severe disruptions in import-dependent countries in Africa and the Middle East.

These changes would induce a catastrophic disruption of global food markets, the researchers conclude. Even a 7% global decline in crop yield would exceed the largest anomaly ever recorded since the beginning of Food and Agricultural Organization observational records in 1961. Under the largest war scenario, more than 75% of the planet would be starving within two years.

Researchers considered whether using crops fed to livestock as human food or reducing food waste could offset caloric losses in a war's immediate aftermath, but the savings were minimal under the large injection scenarios.

Moreover, the ozone layer would be destroyed by the heating of the stratosphere, producing more ultraviolet radiation at the surface, and we need to understand that impact on food supplies too.

The data tell us one thing: We must prevent a nuclear war from ever happening.

Lili Xia, Global food insecurity and famine from reduced crop, marine fishery and livestock production due to climate disruption from nuclear war soot injection, Nature Food (2022). DOI: 10.1038/s43016-022-00573-0. www.nature.com/articles/s43016-022-00573-0

Comment by Dr. Krishna Kumari Challa yesterday

Weird and wonderful world of fungi shaped by evolutionary bursts, study finds

Scientists  have discovered that the vast anatomical variety of fungi stems from evolutionary increases in multicellular complexity.

Most people recognize that fungi come in an assortment of shapes and sizes.

We didn't know till now how this variety was distributed across the different types of fungi. Which groups are the most varied when considering all parts of the fungal body plan? Which are the least? How has this variety accumulated and diminished through time? What has shaped these patterns in disparity?

What scientists now found  was that fungal disparity has evolved episodically through time, and that the evolution of multicellularity in different fungi appears to open the door for greater morphological variety. They saw increases in disparity associated with both the emergence of the first multicellular fungi, and then the evolution of complex fruiting bodies such as mushrooms and saddles in dikaryotic species. These fungi are defined by the inclusion of a dikaryon, a cell with two separate nuclei, in their life cycles.

The main implication is that these results align with those of analyses of animal disparity. Both kingdoms present clumpy distributions of anatomical variety which have evolved intermittently through time.

The world of fungi is defined by bright colors, strange shapes, and stranger anatomies. This study analyses demonstrate that this breath-taking anatomical variety has evolved in bursts, driven by evolutionary increases in multicellular complexity.

Thomas Smith, Evolution of fungal phenotypic disparity, Nature Ecology & Evolution (2022). DOI: 10.1038/s41559-022-01844-6. www.nature.com/articles/s41559-022-01844-6

Comment by Dr. Krishna Kumari Challa on Monday

How a slender, snake-like robot could give doctors new ways to save lives

Researchers are building very slender, flexible and extensible robots, a few millimeters in diameter, for use in surgery and industry. You might call it "zoobotics."

Unlike humanoid robots, so-called continuum robots feature long, limbless bodies—not unlike a snake's—that allows them to access difficult-to-reach places.

Consider a neurosurgeon who needs to remove a brain tumor. Using a traditional, rigid surgical tool, the surgeon has to reach the cancerous mass by following a straight path into the brain, and risk poking through—and damaging—vital tissue.

Roboticists envisions a day when one of her snake-like robots, guided by a surgeon, would be able to take a winding path around the vital tissue but still reach the precise surgical site. Previously inoperable brain tumors might suddenly become operable.

It could revolutionize surgery. So they are also developing a more advanced generation of continuum robots that are equipped with sensors and can partially steer themselves. A surgeon would have to operate the robot remotely with a computer, but the robot would know how to avoid obstacles and recognize its destination. A surgeon could deploy one of these robots to collect a tissue sample from the abdomen, for instance, or inject a cancer drug directly into a tumor in the lungs.

There are uses outside the human body, too. A continuum robot could slide through the interior of a jet engine, inspecting it for damage. 

https://techxplore.com/news/2022-08-slender-snake-like-robot-doctor...

Comment by Dr. Krishna Kumari Challa on Monday

Matter at extreme conditions of very high temperature and pressure turns out to be remarkably simple and universal

Scientists at Queen Mary University of London have made two discoveries about the behavior of "supercritical matter"—matter at the critical point where the differences between liquids and gases seemingly disappear.
While the behavior of matter at reasonably low temperature and pressure was well understood, the picture of matter at high temperature and pressure was blurred. Above the critical point, differences between liquids and gases seemingly disappear, and the supercritical matter was thought to become hot, dense and homogeneous.

The researchers believed there was new physics yet to be uncovered about this matter at the supercritical state.

By applying two parameters—the heat capacity and the length over which waves can propagate in the system, they made two key discoveries. First, they found that there is a fixed inversion point between the two where matter changes its physical properties—from liquid-like to gas-like. They also found that this inversion point is remarkably close in all systems studied, telling us that the supercritical matter is intriguingly simple and amenable to new understanding.

As well as fundamental understanding of the states of matter and the phase transition diagram, understanding supercritical matter has many practical applications; hydrogen and helium are supercritical in gas giant planets such as Jupiter and Saturn, and therefore govern their physical properties. In green environmental applications, supercritical fluids have also proved to be very efficient at destroying hazardous wastes, but engineers increasingly want guidance from theory in order to improve efficiency of supercritical processes.

The asserted universality of the supercritical matter opens a way to a new physically transparent picture of matter at extreme conditions. This is an exciting prospect from the point of view of fundamental physics as well as understanding and predicting supercritical properties in green environmental applications, astronomy and other areas.

C. Cockrell et al, Double universality of the transition in the supercritical state, Science Advances (2022). DOI: 10.1126/sciadv.abq5183. www.science.org/doi/10.1126/sciadv.abq5183

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