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Comment by Dr. Krishna Kumari Challa on November 5, 2020 at 5:55am

Early big-game hunters of the Americas were female, researchers suggest

For centuries, historians and scientists mostly agreed that when early human groups sought food, men hunted and women gathered. However, a 9,000-year-old female hunter burial in the Andes Mountains of South America reveals a different story, according to new research conducted.

An archaeological discovery and analysis of early burial practices overturns the long-held 'man-the-hunter' hypothesis.

These findings are particularly timely in light of contemporary conversations surrounding gendered labour practices and inequality. Labour practices among recent hunter-gatherer societies are highly gendered, which might lead some to believe that sexist inequalities in things like pay or rank are somehow 'natural.' But it's now clear that sexual division of labour was fundamentally different—likely more equitable—in our species' deep hunter-gatherer past.

During archaeological excavations at a high-altitude site called Wilamaya Patjxa in what is now Peru, researchers found an early burial that contained a hunting toolkit with projectile points and animal-processing tools. The objects accompanying people in death tend to be those that accompanied them in life, researchers said. It was determined that the hunter was likely female based on findings by the team's osteologist, James Watson of The University of Arizona. Watson's sex estimate was later confirmed by dental protein analysis.

 The surprising discovery of an early female hunter burial led the team to ask whether she was part of a broader pattern of female hunters or merely a one-off. Looking at published records of late Pleistocene and early Holocene burials throughout North and South America, the researchers identified 429 individuals from 107 sites. Of those, 27 individuals were associated with big-game hunting tools—11 were female and 15 were male. The sample was sufficient to "warrant the conclusion that female participation in early big-game hunting was likely nontrivial," researchers said. Moreover, the analysis identified the Wilamaya Patjxa female hunter as the earliest hunter burial in the Americas.

Statistical analysis shows that somewhere between 30 to 50 percent of hunters in these populations were female, the study said. This level of participation stands in stark contrast to recent hunter-gatherers, and even farming and capitalist societies, where hunting is a decidedly male activity with low levels of female participation, certainly under 30 percent

R. Haas el al., "Female hunters of the early Americas," Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abd0310

https://phys.org/news/2020-11-early-big-game-hunters-americas-femal...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 10:42am

Baking Soda Boosts T Cells’ Ability to Fight Leukemia

Infusions of donor T cells to fight the cancer often fail, but sodium bicarbonate can counter lactic acid produced by leukemia cells, potentially improving remission rates in mice and humans.

https://www.the-scientist.com/news-opinion/baking-soda-boosts-t-cel...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 10:38am

Researchers discover how birds deal with gusty conditions

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 10:31am

Radical diagnostic could save millions of people at risk of dying from blood loss

In a world-first outcome that could save more than two million lives globally each year, researchers have developed a diagnostic using a glass slide, Teflon film and a piece of paper that can test for levels of fibrinogen concentration in blood in less than four minutes. Fibrinogen is a protein found in blood that is needed for clotting. When a patient experiences traumatic injury, such as a serious car accident, or major surgery and childbirth complications, fibrinogen is required in their blood to prevent major haemorrhaging and death from blood loss. Typically, heavily bleeding patients must be transported to a hospital or emergency centre where they undergo diagnostic tests before being treated. These tests are time consuming and costly as they require expensive equipment, specialised/trained personnel and can take up to half an hour.

When a patient is bleeding heavily and has received several blood transfusions, their levels of fibrinogen drop. Even after dozens of transfusions, patients keep bleeding. What they need is an injection of fibrinogen. However, if patients receive too much fibrinogen, they can also die.

This new diagnostic can eliminate the preparation time, labour and transportation difficulties of traditional techniques used in the hospital. It can diagnose hypofibrinogenemia in critically bleeding patients anywhere in the world, and can drastically reduce the time to treatment needed for fibrinogen replacement therapy. The test can take less than four minutes, about five times faster than the current gold standard methods.

1. Marek Bialkower, Clare A. Manderson, Heather McLiesh, Rico F. Tabor, Gil Garnier. Paper Diagnostic for Direct Measurement of Fibrinogen Concentration in Whole Blood. ACS Sensors, 2020; DOI: 10.1021/acssensors.0c01937

https://www.sciencedaily.com/releases/2020/10/201029105018.htm#:~:t....

https://researchnews.cc/news/3377/Radical-diagnostic-could-save-mil...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 9:39am

3.2 billion images and 720,000 hours of video are shared online daily. Can you sort real from fake?

Here is how you can do it …..This article explains how you can do it …..

https://theconversation.com/3-2-billion-images-and-720-000-hours-of...

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Physicists hone in on the perfect clock

Physicists have measured the energy of a thorium-229 nucleus’s lowest excited state, called thorium-229m, to the highest precision so far. This tiny nucleus could make for the most accurate clock yet if we could count the tick-tocks of the transition between the ground state of the th... — the lowest of all nuclear excited states. A nuclear clock would be less affected by external electromagnetic fields than today’s atomic clocks are, which lose a frankly unacceptable one second every 13 billion years.

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 8:11am

Hot or cold, weather alone has no significant effect on COVID-19 spread

The link between weather and COVID-19 is complicated. Weather influences the environment in which the coronavirus must survive before infecting a new host. But it also influences human behaviour, which moves the virus from one host to another.

Aa new study finding that temperature and humidity do not play a significant role in coronavirus spread.

That means whether it's hot or cold outside, the transmission of COVID-19 from one person to the next depends almost entirely on human behaviour.

The effect of weather is low and other features such as mobility have more impact than weather. In terms of relative importance, weather is one of the last parameters.

Across scales, the scientists found that the weather had nearly no influence. When it was compared with other factors using a statistical metric that breaks down the relative contribution of each factor toward a particular outcome, the weather's relative importance at the county scale was less than 3%, with no indication that a specific type of weather promoted spread over another.

In contrast, the data showed the clear influence of human behavior—and the outsized influence of individual behaviors. Taking trips and spending time away from home were the top two contributing factors to COVID-19 growth, with a relative importance of about 34% and 26% respectively. The next two important factors were population and urban density, with a relative importance of about 23% and 13% respectively.

Sajad Jamshidi et al, Global to USA County Scale Analysis of Weather, Urban Density, Mobility, Homestay, and Mask Use on COVID-19, International Journal of Environmental Research and Public Health (2020). DOI: 10.3390/ijerph17217847

https://medicalxpress.com/news/2020-11-hot-cold-weather-significant...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 8:00am

COVID-19 'super-spreading' events play outsized role in overall disease transmission

There have been many documented cases of COVID-19 "super-spreading" events, in which one person infected with the SARS-CoV-2 virus infects many other people. But how much of a role do these events play in the overall spread of the disease? A new study  suggests that they have a much larger impact than expected.

The study of about 60 super-spreading events shows that events where one person infects more than six other people are much more common than would be expected if the range of transmission rates followed statistical distributions commonly used in epidemiology.

Based on their findings, the researchers also developed a mathematical model of COVID-19 transmission, which they used to show that limiting gatherings to 10 or fewer people could significantly reduce the number of super-spreading events and lower the overall number of infections.

Super-spreading events are likely more important than most of us had initially realized. Even though they are extreme events, they are probable and thus are likely occurring at a higher frequency than we thought. If we can control the super-spreading events, we have a much greater chance of getting this pandemic under control, according to this study.

Felix Wong et al, Evidence that coronavirus superspreading is fat-tailed, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2018490117

https://medicalxpress.com/news/2020-11-covid-super-spreading-events...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 7:45am

Two centuries of Monarch butterflies show evolution of wing length

Monarch butterflies are known for their annual, multi-generation migrations in which individual insects can fly for thousands of miles. But Monarchs have also settled in some locations where their favorite food plants grow year round, so they no longer need to migrate.

Researchers now 

took a deep dive into museum collections to see how migration has shaped the species. Monarchs are native to North America, but have also established non-migrating populations in the Caribbean, Central and South America, and islands in the Pacific and Atlantic oceans. These island-hopping butterflies may have been blown by storms before being lucky enough to reach dry land.

Monarchs that established new, non-migrating populations also had those larger wings. But over time, the wings of these colonists got smaller.

The shift between longer and shorter wings shows two opposite selection forces at work. Migration selects for longer, larger forewings while non-migration seems to relax this and lead to smaller wings.

Alternatively, wing size could be influenced by other environmental factors depending on where butterflies are hatched and grow up. The non-migrating butterflies retained their smaller wings, showing that the effect is due to genetics and not the rearing environment.

These findings provide a compelling example of how migration-associated traits may be favoured during the early stages of range expansion, and also the rate of reductions in those same traits upon loss of migration.

Micah G. Freedman et al, Two centuries of monarch butterfly collections reveal contrasting effects of range expansion and migration loss on wing traits, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2001283117

New study confirms that migration leads to larger wings in monarch ...

https://phys.org/news/2020-11-centuries-monarch-butterflies-evoluti...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 7:33am

Self-watering soil could transform farming

A new type of soil created by engineers  can pull water from the air and distribute it to plants, potentially expanding the map of farmable land around the globe to previously inhospitable places and reducing water use in agriculture at a time of growing droughts.

The team's atmospheric water irrigation system uses super-moisture-absorbent gels to capture water from the air. When the soil is heated to a certain temperature, the gels release the water, making it available to plants. When the soil distributes water, some of it goes back into the air, increasing humidity and making it easier to continue the harvesting cycle.

 Xingyi Zhou et al, Super Moisture Absorbent Gels for Sustainable Agriculture via Atmospheric Water Irrigation, ACS Materials Letters (2020). DOI: 10.1021/acsmaterialslett.0c00439

https://phys.org/news/2020-11-self-watering-soil-farming.html?utm_s...

Comment by Dr. Krishna Kumari Challa on November 4, 2020 at 7:29am

Biologists shed light on mystery of how microbes evolve and affect hosts

researchers  have found that as microbes evolve and adapt to their unique hosts, they become less beneficial to hosts of other genotypes.

The findings suggest that there is probably not one universally healthy microbiome. Rather, transplanted microbes might need time to adapt to a new host before they bring benefits. Microbes became better adapted to their hosts through the evolution of more, rather than less, cooperation.

Rebecca T. Batstone et al, Experimental evolution makes microbes more cooperative with their local host genotype, Science (2020). DOI: 10.1126/science.abb7222

https://phys.org/news/2020-11-biologists-mystery-microbes-evolve-af...

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When we put microbes from the beginning and the end of the experiment back onto hosts, we found they did best with the same hosts they evolved on, suggesting they adapted to their local host," said Batstone. "The derived microbes were more beneficial when they shared an evolutionary history with their host."

The researchers say the finding suggests that evolution might favour cooperation and that scientists might be able to use experimental evolution in a laboratory setting to make microbes that provide more benefits to their hosts.

"When plants or even animals arrive in new environments, perhaps as invasive species or because they are responding to a changing climate, the microbes they encounter may be initially poor partners. But these microbes might rapidly adapt and develop a more beneficial relationship

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