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Comment by Dr. Krishna Kumari Challa on January 4, 2021 at 11:53am

Discovery: How potato beetles beat pesticides

Potato beetles can beat pesticides cleverly. Even small doses of the neonicotinoid pesticide, imidacloprid, can alter how the beetle manages its DNA. To fend off the pesticides, the new research suggests, the beetle may not need to change its underlying genetic code. Instead, the team found that beetles respond by altering the regulation of their DNA, turning certain genes on or off in a process called “DNA methylation." These so-called epigenetic changes allow beetles to quickly ramp up biological defense mechanisms—perhaps putting into overdrive already-existing genes that allow the beetle to tolerate a broad range of toxins found in potato plants.

A flush of enzymes or faster rate of excretion may let the insect stymie each new pesticide with the same ancient biochemical tools that it uses to overcome natural plant defenses—rather than relying on the ponderous evolutionary process of random mutations appearing in key genes, that would slowly cause a pesticide to become less effective.

Most important, the new study shows that these changes—triggered by even small doses of the pesticide—can be passed on to descendants across at least two generations. 

https://researchnews.cc/news/4423/Discovery--How-colorado-potato-be...

Comment by Dr. Krishna Kumari Challa on January 3, 2021 at 1:30pm

How Scientists, unlike people who do their own research on the net, Know The Approved COVID-19 Vaccines Are Safe

https://www.sciencealert.com/how-scientists-know-the-approved-covid...

Comment by Dr. Krishna Kumari Challa on January 2, 2021 at 7:21am

Desalination breakthrough could lead to cheaper water filtration

Producing clean water at a lower cost could be on the horizon after researchers from The University of Texas at Austin and Penn State solved a complex problem that had baffled scientists for decades, until now. Desalination membranes remove salt and other chemicals from water, a process critical to the health of society, cleaning billions of gallons of water for agriculture, energy production and drinking. The idea seems simple  push salty water through and clean water comes out the other side  but it contains complex intricacies that scientists are still trying to understand. The research team, in partnership with DuPont Water Solutions, solved an important aspect of this mystery, opening the door to reduce costs of clean water production. The researchers determined desalination membranes are inconsistent in density and mass distribution, which can hold back their performance. Uniform density at the nanoscale is the key  to increasing how much clean water these membranes can create.

The paper documents an increase in efficiency in the membranes tested by 30%-40%, meaning they can clean more water while using significantly less energy. That could lead to increased access to clean water and lower water bills for individual homes and large users alike.

Reverse osmosis membranes work by applying pressure to the salty feed solution on one side. The minerals stay there while the water passes through. Although more efficient than non-membrane desalination processes, it still takes a large amount of energy, the researchers said, and improving the efficiency of the membranes could reduce that burden.

https://news.utexas.edu/2020/12/31/desalination-breakthrough-could-...

https://researchnews.cc/news/4396/Desalination-breakthrough-could-l...

Comment by Dr. Krishna Kumari Challa on January 1, 2021 at 11:23am

Multiple mosquito blood meals accelerate malaria transmission

Multiple bouts of blood feeding by mosquitoes shorten the incubation period for malaria parasites and increase malaria transmission potential, according to a study published recently.  Given that mosquitoes feed on blood multiple times in natural settings, the results suggest that malaria elimination may be substantially more challenging than suggested by previous experiments, which typically involve a single blood meal.

The results show that an additional blood feed three days after infection with P. falciparum accelerates the growth of the malaria parasite, thereby shortening the incubation period required before transmission to humans can occur. Incorporating these data into a mathematical model across sub-Saharan Africa reveals that malaria transmission potential is likely higher than previously thought, making disease elimination more difficult. In addition, parasite growth is accelerated in genetically modified mosquitoes with reduced reproductive capacity, suggesting that control strategies using this approach, with the aim of suppressing Anopheles populations, may inadvertently favor malaria transmission. The data also suggest that parasites can be transmitted by younger mosquitoes, which are less susceptible to insecticide killing, with negative implications for the success of insecticide-based strategies. Taken together, the results suggest that younger mosquitoes and those with reduced reproductive ability may provide a larger contribution to infection than previously thought.

Shaw WR, Holmdahl IE, Itoe MA, Werling K, Marquette M, Paton DG, et al. (2020) Multiple blood feeding in mosquitoes shortens the Plasmodium falciparum incubation period and increases malaria transmission potential. PLoS Pathog 16(12): e1009131. DOI: 10.1371/journal.ppat.1009131

https://medicalxpress.com/news/2020-12-multiple-mosquito-blood-meal...

Comment by Dr. Krishna Kumari Challa on January 1, 2021 at 9:51am

Brain damage of patients with Covid-19

In an in-depth study of how COVID-19 affects a patient's brain, National Institutes of Health researchers consistently spotted hallmarks of damage caused by thinning and leaky brain blood vessels in tissue samples from patients who died shortly after contracting the disease. In addition, they saw no signs of SARS-CoV-2 in the tissue samples, suggesting the damage was not caused by a direct viral attack on the brain. The results were published as a correspondence in the New England Journal of Medicine.

Researchers found that the brains of patients who contract infection from SARS-CoV-2 may be susceptible to microvascular blood vessel damage. The results suggest that this may be caused by the body's inflammatory response to the virus.

Although COVID-19 is primarily a respiratory disease, patients often experience neurological problems including headaches, delirium, cognitive dysfunction, dizziness, fatigue, and loss of the sense of smell. The disease may also cause patients to suffer strokes and other neuropathologies. Several studies have shown that the disease can cause inflammation and blood vessel damage. In one of these studies, the researchers found evidence of small amounts of SARS-CoV-2 in some patients' brains. Nevertheless, scientists are still trying to understand how the disease affects the brain.

In this study, the researchers conducted an in-depth examination of brain tissue samples from 19 patients who had died after experiencing COVID-19 between March and July 2020. The patients died at a wide range of ages, from 5 to 73 years old. They died within a few hours to two months after reporting symptoms. Many patients had one or more risk factors, including diabetes, obesity, and cardiovascular disease. Eight of the patients were found dead at home or in public settings. Another three patients collapsed and died suddenly.

Researchers  saw multifocal areas of damage that is usually associated with strokes and neuroinflammatory diseases. 

Finally, the researchers saw no signs of infection in the brain tissue samples even though they used several methods for detecting genetic material or proteins from SARS-CoV-2.

The results suggest that the damage we saw may not have been not caused by the SARS-CoV-2 virus directly infecting the brain.

Myoung-Hwa Lee et al, Microvascular Injury in the Brains of Patients with Covid-19, New England Journal of Medicine (2020). DOI: 10.1056/NEJMc2033369

https://medicalxpress.com/news/2020-12-results-deceased-covid-patie...

Comment by Dr. Krishna Kumari Challa on January 1, 2021 at 9:45am

Pfizer vaccine results published in peer-reviewed journal

The full results of a clinical trial for the Pfizer-BioNTech COVID-19 vaccine were published in the New England Journal of Medicine  re cently

The full trial included almost 44,000 volunteers, several thousand more than the number seen in prior analyses. Around half received the vaccine and the rest a placebo.

The paper confirmed that a two-dose regimen of BNT162b2 was 95 percent effective in preventing COVID-19 infection.

The vaccine worked similarly across "age, sex, race, ethnicity, baseline body-mass index, and the presence of coexisting conditions," the paper said.

Among 10 cases of severe COVID-19 after the first dose, nine occurred in placebo recipients and one in a person who received the vaccine.

The editorial that accompanied the study did flag certain "minor issues."

"The number of severe cases of COVID-19 (one in the vaccine group and nine in the placebo group) is too small to draw any conclusions about whether the rare cases that occur in vaccinated persons are actually more severe," it said.

Other questions include whether unexpected safety issues may arise when the number of people vaccinated grows to millions and possibly billions of people.

Also unknown is whether more side effects will emerge with longer follow-up, how long the vaccine remains effective, whether it will limit transmission, and how it will work in children, pregnant women, and immunocompromised patients.

 Fernando P. Polack et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine, New England Journal of Medicine (2020). DOI: 10.1056/NEJMoa2034577

https://medicalxpress.com/news/2020-12-pfizer-vaccine-results-publi...

Comment by Dr. Krishna Kumari Challa on January 1, 2021 at 9:41am

Published data from Moderna COVID-19 vaccine trial show 94.1 percent efficacy

A peer-reviewed paper published in The New England Journal of Medicine provides data from the much-anticipated COVE study, which evaluated mRNA-1273, a vaccine candidate against COVID-19 manufactured by Moderna, Inc. Results from the primary analysis of the study, which will continue for two years, provide evidence that the vaccine can prevent symptomatic infection. Among the more than 30,000 participants randomized to receive the vaccine or a placebo, 11 of those in the vaccine group developed symptomatic COVID-19 compared to 185 participants who received the placebo, demonstrating 94.1 percent efficacy in preventing symptomatic COVID-19. Cases of severe COVID-19 occurred only in participants who received the placebo.

The study enrolled 30,420 adult participants at 99 U.S. sites, including over 600 participants enrolled at the Brigham. Eligible participants were 18 years old or older with no known history of SARS-CoV-2 infection, and whose locations or circumstances put them at appreciable risk of SARS-CoV-2 infection and/or high risk of severe COVID-19. The race and ethnicity proportions of the trial were generally representative of U.S. demographics (79 percent white; 10 percent Black or African American; 20 percent Hispanic or Latino participants).

Participants received their first injection between July 27 and Oct. 23, 2020, followed by a second injection 28 days later. Each injection, given intramuscularly, had a volume of 0.5 mL, containing 100 μg of mRNA-1273 or saline placebo.

In the placebo group, 185 participants developed symptomatic COVID-19 illness; in the vaccine group, 11 participants did. In secondary analyses, the vaccine's efficacy was similar across groups of key interest, including those who already had antibodies against SARS-CoV-2 at the time of enrollment (indicating previous infection with COVID-19) and among those who were 65 years of age or older. Thirty participants had severe COVID-19—all in the placebo group.

Starting from randomization, cases of COVID-19 and severe COVID-19 were continuously monitored throughout the trial by the Data Safety Monitoring Board, empaneled by the NIAID. Participants were closely monitored for adverse events in the weeks following their injection. Investigators have collected and will continue to collect data on any serious adverse events or adverse events that require medical attention through two years post-injection.

Overall, reactions to the vaccine were mild—about half of recipients experienced fatigue, muscle aches, joint pain and headaches, more so after the second dose. In most cases, these effects started about 15 hours after the vaccine and resolved after two days without sequelae. A similar number of adverse events were reported in the placebo and vaccine groups.

Lindsey R. Baden et al, Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine, New England Journal of Medicine (2020). DOI: 10.1056/NEJMoa2035389

https://medicalxpress.com/news/2020-12-published-moderna-covid-vacc...

Pfizer vaccine results published in peer-reviewed journal

Comment by Dr. Krishna Kumari Challa on December 31, 2020 at 10:46am

The Biggest Science News of 2020

Neanderthal DNA surprises in modern humans, the first blood test for Alzheimer’s, a discovery of new human salivary glands, and, oh yeah, a pandemic

https://www.the-scientist.com/news-opinion/the-biggest-science-news...

Comment by Dr. Krishna Kumari Challa on December 31, 2020 at 9:43am

AI-controlled vertical farms promise revolution in food production

With the world population hurtling towards 8 billion, we face a food problem. Human population increases geometrically, while food production increases only arithmetically. That means the more civilization grows and thrives, the more likely it will be unable to keep up with demands for food.

While advances in food technology have helped to cope with the situation to some extent, there remains great concern for the future of food production as the Earth's population soars on a planet with shrinking farming real estate. National Geographic recently predicted that by 2050, there will be more than two billion additional mouths to feed while the Earth's irrigable land remains essentially the same.

An agricultural-technical startup thinks it might just have an answer. 

To do so,they have constructed climate-controlled vertical farms that are very promising.

These upright farms take up only 2 acres yet produce 720 acres worth of fruit and vegetables. Lighting, temperature and watering are controlled by AI-controlled robots. Sunlight is emulated by LED panels, so food is grown in optimal conditions 24/7. And water is recycled and evaporated water recaptured so there is virtually no waste.

The operation is so efficient it uses 99 percent less land and 95 percent less water than normal farming operations.

It is so efficient that these rows of hanging plants produce 400 times more food per acre than a traditional farm.

AI monitors growth patterns and constantly adjusts environmental factors such as temperature, water and light patterns to ensure ever-more efficient and economical output.

https://www.plenty.ag/about-us/

https://techxplore.com/news/2020-12-ai-controlled-vertical-farms-re...

Comment by Dr. Krishna Kumari Challa on December 31, 2020 at 8:55am

Torpor: a neat survival trick once thought rare in animals is actually widespread

Life is hard for small animals in the wild, but they have many solutions to the challenges of their environment. One of the most fascinating of these strategies is torpor. Not, to be confused with sleep or Sunday afternoon lethargy, torpor is a complex response to the costs of living.

To enter torpor, an animal decreases its metabolism, reducing its energy requirements. A torpid animal will often be curled in a tight ball in its nest and look like it's sleeping.

Once thought to occur only in birds and mammals in the Northern Hemisphere where winters are more pronounced, we now know torpor is widespread in small Australian mammals, and has also been observed in many small Australian bird species.

Birds and mammals are endotherms and can maintain a high and constant body temperature independent of the environmental temperature, thanks to their high metabolic rate. This allows them to be active across a wide range of environments.

The downside? This high metabolic rate requires a lot of food to fuel it. By reducing the metabolism in a very controlled manner and entering torpor, an animal can live on less energy.

With a lower metabolic rate, the animal's body temperature decreases—sometimes by as much as 30°C. How low it goes can depend on the extent of the metabolic reduction and the temperature of animal's immediate environment. The reduced body temperature further lowers the metabolic rate.

Torpor is an extremely effective survival strategy for small endotherms. Many pregnant and lactating bats and marsupials, and even the echidna, synchronise torpor with reproduction to cope with the energetic costs of mating, pregnancy or lactation.

There are two main types of torpor: daily torpor and hibernation.

Animals that use daily torpor can do so for approximately 3-6 hours a day as needed.

Daily torpor is common in, but not exclusive to, endotherms living in arid areas, such as the fat-tailed dunnart. This species is a carnivorous marsupial and has a diet of insects and other invertebrates, which may be in short supply in winter.

Weighing approximately 12 grams as adults, the fat-tailed dunnart may need to eat its body weight in food each day. When finding enough food is difficult, it uses torpor; foraging in the early part of the night then entering torpor in the early morning. Fat-tailed dunnarts reduce their metabolic rate, and subsequently their body temperature, from 35 °C to approximately 15°C, or the temperature of their underground nest.

Animals that hibernate lower their metabolic rate further and have longer torpor bouts than those that use daily torpor. An example of an Australian hibernator is the eastern pygmy possum, a 40g marsupial found in south eastern Australia that hibernates regularly, decreasing its body temperature from approximately 35 °C to as low as 5°C.

When active, this species can survive for less than half a day on 1g of fat, but when hibernating, it can survive for two weeks.

https://theconversation.com/torpor-a-neat-survival-trick-once-thoug...

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