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Comment by Dr. Krishna Kumari Challa on December 5, 2020 at 9:31am

Creation of a levitating liquid layers

Comment by Dr. Krishna Kumari Challa on December 5, 2020 at 9:29am

Inverted pendulum with a vertically oscillated pivot.

Comment by Dr. Krishna Kumari Challa on December 5, 2020 at 9:27am

Anti-gravity: How a boat can float upside down

Here on Earth, everything is subject to gravity—it makes objects fall to the ground and rivers flow from higher ground to the sea. We know what would happen without it, thanks to images of astronauts floating around their spaceship. But could we design an anti-gravity machine, something that would make objects fall upwards, oceans levitate, and boats float upside down?

Boats floating at the interfaces of the levitating liquid layer.

https://theconversation.com/anti-gravity-how-a-boat-can-float-upsid...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:55am

Lab-Grown Chicken Meat Is Finally Going on Sale in a World First

Lab-grown chicken will soon be available in restaurants in Singapore after the country became the first to green-light meat created without slaughtering any animals.

Consumption of regular meat is an environmental threat as cattle produce methane, a potent greenhouse gas, while logging forests to make way for animals destroys natural barriers against climate change.

Demand for sustainable meat alternatives is rising due to growing pressure from consumers about the environment and animal welfare, but other products in the market are plant-based.

There were concerns that lab-grown varieties would be too expensive, but a spokesman for Eat Just said the company had made "considerable progress" in lowering the cost.

https://www.sciencealert.com/singapore-will-be-the-first-country-to...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:53am

'Oldest' Baby Ever Born Is a 28-Year-Old Record-Breaker Almost as Old as Her Mother

A baby born in Tennessee can lay claim to being the oldest baby ever born, in that she is believed to be the longest-frozen embryo ever successfully delivered in a live birth.

Molly Everette Gibson was born on October 26, but her birthday was an event literally decades in the making. She was born from an embryo frozen in October 1992 – a mind-boggling 28 years ago.

And effectively a lifetime ago, too. Molly's mother, Tina, is now 29, and was herself only born about 18 months earlier than when Molly was frozen in her embryonic form.

In a manner of speaking, they've both been on this planet for about the same amount of time, even though they're a generation apart.

The incredible strangeness of this story gets even stranger.

When Molly was born, she broke the record held by another child who was previously the longest-frozen embryo ever delivered. That child – Emma Wren Gibson – was frozen as an embryo for 24 years before being born in 2017.

Emma also happens to be Molly's older sister, meaning this single family's two children were the two longest-frozen embryos ever to be born.

That might sound weird – as if the Gibson family, who previously struggled with infertility for several years. 

Molly and Emma are full genetic siblings that were frozen at the same time, after being anonymously donated by their biological parents, whose identity has not been disclosed.

In other words, the two sisters are actual sisters – in addition to being adopted sisters – who were both carried and delivered by their adoptive mother, Tina. 

It's just that it took a little longer than usual, decades in fact, for these patient little ones to have their time in the sun.

The births were facilitated by staff at the National Embryo Donation Centre (NEDC), in Knoxville, a Christian-based nonprofit that receives donated embryos from biological parents who have gone through in vitro fertilisation (IVF), but who have decided, for whatever reason, not to go through with using the embryo for a pregnancy.

In such cases, rather than letting the embryos be discarded, the parents can donate their frozen embryos to the NEDC, which stores them for later use, working with would-be parents (most of them with infertility), who apply to adopt, carry, and deliver an embryo.

About 75 percent of donated embryos survive the freezing and thawing process, the NEDC says, and about 49 percent of transfers result in a live birth.

Fortunately, IVF success rates with frozen embryos have caught up in recent years, and are now thought to be about as successful as treatments using fresh embryos.

https://www.sciencealert.com/oldest-baby-ever-born-is-a-27-year-old...

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Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:26am

Voyager spacecraft detect new type of solar electron burst

In a new study, a team of physicists led by the University of Iowa report the first detection of bursts of cosmic ray electrons accelerated by shock waves originating from major eruptions on the sun. The detection, made by instruments onboard both the Voyager 1 and Voyager 2 spacecraft, occurred as the Voyagers continue their journey outward through interstellar space, thus making them the first craft to record this unique physics in the realm between stars.

These newly detected electron bursts are like an advanced guard accelerated along magnetic field lines in the interstellar medium; the electrons travel at nearly the speed of light, some 670 times faster than the shock waves that initially propelled them. The bursts were followed by plasma wave oscillations caused by lower-energy electrons arriving at the Voyagers' instruments days later—and finally, in some cases, the shock wave itself as long as a month after that.

The shock waves emanated from coronal mass ejections, expulsions of hot gas and energy that move outward from the sun at about one million miles per hour. Even at those speeds, it takes more than a year for the shock waves to reach the Voyager spacecraft, which have traveled further from the sun (more than 14 billion miles and counting) than any human-made object.

Astronomical Journal (2020). DOI: 10.3847/1538-3881/abc337

https://phys.org/news/2020-12-voyager-spacecraft-solar-electron.htm...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:23am

Climate change is resulting in profound, immediate and worsening health impacts, over 120 researchers say

This year's annual report of The Lancet Countdown on Health and Climate Change, released today, presents the latest data on health impacts from a changing climate.

Among its results, the report found there were 296,000 heat-related premature deaths in people over 65 years in 2018 (a 54% increase in the last two decades), and that global yield potential for major crops declined by 1.8–5.6% between 1981 and 2019.

based on current population data, 145 million people face potential inundation with global mean sea-level rise of one metre. This jumps to 565 million people with a five metre sea-level rise.

Unless urgent action is taken, the health consequences of climate change will worsen. A globally coordinated effort tackling COVID-19 and climate change in unison is vital, and will mean a triple win: better public health, a more sustainable economy and environmental protection.

https://theconversation.com/climate-change-is-resulting-in-profound...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:17am

Common pipe alloy can form cancer-causing chemical in drinking water

Rusted iron pipes can react with residual disinfectants in drinking water distribution systems to produce carcinogenic hexavalent chromium in drinking water, reports a study by engineers .

Chromium is a metal that occurs naturally in the soil and groundwater. Trace amounts of trivalent chromium eventually appear in the drinking water and food supply and are thought to have neutral effects on health. Chromium is often added to iron to make it more resistant to corrosion.

Certain chemical reactions can change chromium atoms into a hexavalent form that creates cancer-causing genetic mutations in cells.

Cheng Tan et al, Hexavalent Chromium Release in Drinking Water Distribution Systems: New Insights into Zerovalent Chromium in Iron Corrosion Scales, Environmental Science & Technology (2020). DOI: 10.1021/acs.est.0c03922

https://phys.org/news/2020-12-common-pipe-alloy-cancer-causing-chem...

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Engineers invent fast and safe way to store natural gas for useful ...

applications

Natural gas is the cleanest of all fossil fuels, but storing it safely and affordably remains a challenge. Now, engineers from the National University of Singapore (NUS) have devised a method to convert natural gas into a non-explosive solid that can be easily stored and transported. Using a novel, low-toxicity additive mixture they formulated, the conversion can be completed in just 15 minutes—the fastest time so far.

The NUS team worked on a process of converting natural gas into a sold form known as gas hydrates, or combustible ice, which consists of molecules of natural gas trapped in "cages" formed by water molecules. In fact, nature stores natural gas this way, but the process is extremely slow. Other researchers have previously managed to speed it up artificially, but they resorted to using highly toxic additives which are unsafe for both the environment and personnel involved.

The new additive mixture formulated by the NUS researchers contains L-tryptophan, well known as an essential amino acid in people's diet. This muscle-building amino acid can also greatly speed up the caging of natural gas into solid hydrate. The NUS formulation produces the fastest reaction rate to date—more than twice as fast as existing standards—while being less toxic and safer to handle.

Gaurav Bhattacharjee et al. Ultra-rapid uptake and the highly stable storage of methane as combustible ice, Energy & Environmental Science (2020). DOI: 10.1039/D0EE02315A

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:14am

Medicine-carriers made from human cells can cure lung infections

Scientists used human white blood cell membranes to carry two drugs, an antibiotic and an anti-inflammatory, directly to infected lungs in mice.

The nano-sized drug delivery method developed successfully treated both the bacterial growth and inflammation in the mice's lungs. The study, recently published in Communications Biology, shows a potential new strategy for treating infectious diseases, including COVID-19.

If a doctor simply gives two drugs to a patient, they don't go directly to the lungs. They circulate in the whole body, so potentially there's a lot of toxicity. Instead, researchers can load the two types of drugs into these vesicles that specifically target the lung inflammation.

The research team has developed a method to essentially peel the membrane from neutrophils, the most common type of white blood cells that lead the body's immune system response. Once emptied, these membranes can be used as nanovesicles, tiny empty sacks only 100 to 200 nanometers wide, which scientists can then fill with medicine.

These nanovesicles retain some of the properties of the original white blood cells, so when they are injected into a patient, they travel directly to the inflamed area just as the cells would normally, but these nanovesicles carry the medicines that the scientists implanted to attack the infection.

Jin Gao et al, Co-delivery of resolvin D1 and antibiotics with nanovesicles to lungs resolves inflammation and clears bacteria in mice, Communications Biology (2020). DOI: 10.1038/s42003-020-01410-5

https://phys.org/news/2020-12-medicine-carriers-human-cells-lung-in...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:06am

Scientists predict 'optimal' organism stress levels

Scientists have created an evolutionary model to predict how animals should react in stressful situations.

Almost all organisms have fast-acting stress responses, which help them respond to threats—but being stressed uses energy, and chronic stress can be damaging.

The new study—by an international team including the University of Exeter—suggests most animals remain stressed for longer than is optimal after a stress-inducing incident.

The reasons for this are not clear, but one possibility is that there is a limit to how quickly the body can remove stress hormones from circulation.

So scientists have created one of the first mathematical models to understand how organisms have evolved to deal with stressful events. It combines existing research on stress physiology in a variety of organisms with analysis of optimal responses that balance the costs and benefits of stress.

We know stress responses vary hugely between different species and even among individuals of the same species—as we see in humans. This  study is a step towards understanding why stress responses are so variable.

The researchers define stress as the process of an organism responding to "stressors" (threats and challenges in their environment), including both detection and the stress response itself. A key point highlighted in the study is the importance of how predictable threats are.

The model suggests that an animal living in a dangerous environment should have a high "baseline" stress level, while an animal in a safer environment would benefit from being able to raise and reduce stress levels rapidly.

This approach reveals environmental predictability and physiological limits as key factors shaping the evolution of stress responses.

Barbara Taborsky et al, Towards an Evolutionary Theory of Stress Responses, Trends in Ecology & Evolution (2020). DOI: 10.1016/j.tree.2020.09.003

https://phys.org/news/2020-12-scientists-optimal-stress.html?utm_so...

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