After consulting paleofire records from each of the three regions, only one viable possibility remained: New Zealand, where charcoal records showed a major increase in fire activity beginning about the year 1300. This date also coincided with the estimated arrival, colonization, and subsequent burning of much of New Zealand's forested areas by the Māori people.

This was a surprising conclusion, given New Zealand's relatively small land area and the distance (nearly 4,500 miles), that smoke would have travelled to reach the ice core site on James Ross Island.

"Compared to natural burning in places like the Amazon, or Southern Africa, or Australia, you wouldn't expect Māori burning in New Zealand to have a big impact, but it does over the Southern Ocean and the Antarctic Peninsula

--

The study findings are important for a number of reasons. First, the results have important implications for our understanding of Earth's atmosphere and climate. Modern climate models rely on accurate information about past climate to make projections for the future, especially on emissions and concentrations of light-absorbing black carbon linked to Earth's radiative balance. Although it is often assumed that human impacts during preindustrial times were negligible compared to background or natural burning, this study provides new evidence that emissions from human-related burning have impacted Earth's atmosphere and possibly its climate far earlier, and at scales far larger, than previously imagined.

part2

Second, fallout from biomass burning is rich in micronutrients such as iron. Phytoplankton growth in much of the Southern Ocean is nutrient-limited so the increased fallout from Māori burning probably resulted in centuries of enhanced phytoplankton growth in large areas of the Southern Hemisphere.

Third, the results refine what is known about the timing of the arrival of the Māori in New Zealand, one of the last habitable places on earth to be colonized by humans. Māori arrival dates based on radiocarbon dates vary from the 13^th to 14^th century, but the more precise dating made possible by the ice core records pinpoints the start of large scale burning by early Māori in New Zealand to 1297, with an uncertainty of 30 years.

"From this study and other previous work this team has done such as on 2,000-year old lead pollution in the Arctic from ancient Rome, it is clear that ice core records are very valuable for learning about past human impacts on the environment. "Even the most remote parts of Earth were not necessarily pristine in preindustrial times."

Hemispheric black carbon increase after the 13th-century Māori arrival in New Zealand, Nature (2021). DOI: 10.1038/s41586-021-03858-9

https://phys.org/news/2021-10-early-human-impacted-earth-atmosphere...

Part 3

How 'ice needles' weave patterns of stones in frozen landscapes

Nature is full of repeating patterns that are part of the beauty of our world. An international team, including a researcher from the University of Washington, used modern tools to explain repeating patterns of stones that form in cold landscapes.

The new study, published Oct. 5 in the Proceedings of the National Academy of Sciences, uses experimental tools to show how needles of ice growing randomly on frozen ground can gradually move rocks into regular, repeating patterns. The team, based mainly in China and Japan, uses a combination of novel experiments and computer modeling to describe these striking features with new theoretical insights.

"The presence of these amazing patterns that develop without any intervention from humans is pretty striking in nature.

One of the reasons for the patterns is needle ice. As the temperature drops, the moisture contained in the soil grows into spikes of ice crystals that protrude from the ground.

"When you go out in the backyard after a freezing night and you feel a little crunch under the foot, you're probably walking on needle ice.

As needle ice forms it tends to push up soil particles, and if there are any, small stones. More needle ice can form on patches of bare soil compared to rock-covered areas. The ice needles will slightly displace any remaining stones in the barer region. Over years, the stones begin to cluster in groups, leaving the bare patches essentially stone-free.

That kind of selective growth involves interesting feedbacks between the size of the stones, the moisture in the soil and the growth of the ice needles.

Watch a video that shows how this happens here:

https://movie-usa.glencoesoftware.com/video/10.1073/pnas.2110670118...

Anyuan Li et al, Ice needles weave patterns of stones in freezing landscapes, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2110670118

https://www.washington.edu/news/2021/10/06/how-ice-needles-weave-pa...

Clinical Trial Testing Automatic Oxygen Control Device for Premature Infants

The consequences are dire for the health of a premature baby — too much oxygen can cause blindness, and too little oxygen can cause brain damage and other negative health effects. Some premature babies need the help of life-saving machines in a neonatal intensive care unit, or NICU, to provide oxygen that eases the struggle to take their first breaths. However, small, personalized adjustments — to either raise or lower the level of oxygen provided — must be made by hand under the careful attention of nurses and respiratory therapists. Now, a clinical trial will test a new device that could make those needed adjustments for premature babies in a NICU — automatically.

Emerging infectious disease caused by a tick-borne nairovirus identified in Japan

A previously unknown virus that can infect humans and cause disease has been identified by scientists in Japan. The novel infectious virus, named Yezo virus, is transmitted by tick bites and causes a disease characterized by fever and a reduction in blood platelets and leucocytes. The discovery was made by researchers at Hokkaido University  and the results have been published in the journal Nature Communications.

At least seven people have been infected with this new virus in Japan since 2014, but, so far, no deaths have been confirmed. The Yezo virus was discovered after a 41-year-old man was admitted to the hospital in 2019 with fever and leg pain after being bitten by an arthropod believed to be a tick while he was walking in a local forest in Hokkaido. He was treated and discharged after two weeks, but tests showed he had not been infected with any known viruses carried by ticks in the region. A second patient showed up with similar symptoms after a tick bite the following year.

Genetic analysis of viruses isolated from blood samples of the two patients found a new type of orthonairovirus, a class of nairovirus, that includes pathogens such as the Crimean-Congo haemorrhagic fever virus. The scientists named it Yezo virus, after a historical Japanese name for Hokkaido, a large island in the north of the country where the virus was discovered. The novel virus was found most closely related to Sulina virus and Tamdy virus, detected in Romania and Uzbekistan, respectively, the latter of which reportedly caused acute fever in humans recently in China.

The scientists then checked blood samples collected from hospital patients who showed similar symptoms after tick bites since 2014. They found additional positive samples from five patients. These patients, including the first two, had a fever and reduced blood platelets and leucocytes, and showed indicators of abnormal liver function.

To determine the likely source of the virus, the research team screened samples collected from wild animals in the area between 2010 and 2020. They found antibodies for the virus in Hokkaido shika deer and raccoons. They also found the virus RNA in three major species of ticks in Hokkaido. The Yezo virus seems to have established its distribution in Hokkaido, and it is highly likely that the virus causes the illness when it is transmitted to humans from animals via ticks.

1. Fumihiro Kodama, Hiroki Yamaguchi, Eunsil Park, Kango Tatemoto, Mariko Sashika, Ryo Nakao, Yurino Terauchi, Keita Mizuma, Yasuko Orba, Hiroaki Kariwa, Katsuro Hagiwara, Katsunori Okazaki, Akiko Goto, Rika Komagome, Masahiro Miyoshi, Takuya Ito, Kimiaki Yamano, Kentaro Yoshii, Chiaki Funaki, Mariko Ishizuka, Asako Shigeno, Yukari Itakura, Lesley Bell-Sakyi, Shunji Edagawa, Atsushi Nagasaka, Yoshihiro Sakoda, Hirofumi Sawa, Ken Maeda, Masayuki Saijo, Keita Matsuno. A novel nairovirus associated with acute febrile illness in Hokkaido, Japan. Nature Communications, 2021; 12 (1) DOI: 10.1038/s41467-021-25857-0

https://www.sciencedaily.com/releases/2021/10/211004104237.htm

Why do ducks move in a row in water?

Riding the waves keeps ducks in a row

The sight of ducklings paddling in a line behind their mother is a common sight in rivers and ponds.

 

But just why do they swim in that formation? Scientists think they have discovered the reason—which could have applications in maritime shipping too.

In a research paper published in the Journal of Fluid Mechanics, naval architecture experts conclude that ducklings benefit from 'wave riding' and 'wave passing."

Using a mathematical and numerical model, the researchers found that when a duckling swims at a 'sweet point' behind its mother a 'destructive wave interference phenomenon' occurs. This causes the wave drag of the duckling to turn positive meaning the baby bird is actually pushed forward by the wave.

Interestingly this wave-riding benefit appears to be passed down to the rest of the ducklings in the line formation. Starting from the third duckling the wave drag of individuals gradually tends towards zero, and a delicate dynamic equilibrium is achieved. Each individual under that equilibrium acts as a wave passer, passing the waves' energy to its trailing companion without any energy losses.

Wave riding and wave passing are probably the principal reasons for the evolution of swimming formation by waterfowl.

This study is the first to reveal the reasons why the formation movement of waterfowl can preserve individuals' energy expenditure.

These principles could be potentially applied to design modern freight carrying vessels, e.g. a water-train, to transport more cargoes without extra fuel cost.

Zhi-Ming Yuan et al, Wave-riding and wave-passing by ducklings in formation swimming, Journal of Fluid Mechanics (2021). DOI: 10.1017/jfm.2021.820

https://phys.org/news/2021-10-ducks-row.html?utm_source=nwletter&am...

Why fast charging reduces the capacity of a car battery

When lithium ions are forced rapidly through a battery, they might get stuck and turn into lithium metal, no longer able to move through the battery.

Fast charging is kind of the Holy Grail. It is what everyone who owns a lithium ion battery based device wants to be able to do.

Inside the battery, however, there is a lot of complicated chemistry that can be sensitive to how fast it is charged. Things can go wrong. Capacity loss is the most critical one.

It is possible to make batteries with very high capacity that might allow you to drive your electric car 1000 km, but after you've charged and discharged it a few times, you would lose about half of that capacity and range.

All rechargeable batteries deteriorate over time, but this negative effect is extra strong when the battery is subjected to fast charging. They have been able to see that the lithium ions, which are so important for the capacity of a battery, are converted into pure lithium metal and are no longer useful. And most importantly: this effect is greatly enhanced by fast charging.

During fast charging, the same number of ions move through the system, but much faster. All ions must find their place in the anode in a much shorter time.

When you charge at double speed, you have to move the same amount of ions and electrons in half the time. The most likely thing is you get these lithium ions building up and they just can't get to the graphite anymore. They get stuck there and there's a lot of heat, a lot of energy being put into them, and so they get reduced to lithium metal.

 Donal P. Finegan et al, Spatial dynamics of lithiation and lithium plating during high-rate operation of graphite electrodes, Energy & Environmental Science (2020). DOI: 10.1039/d0ee01191f

https://techxplore.com/news/2021-10-fast-capacity-car-battery.html?...

The thin line between science and pseudo-science

Scientists Finally Know Why Wisdom Teeth Only Emerge When We're Basically Adults

Homo sapiens don't grow their last few teeth until they're nearly out of the teenage years.

This mystery of the molars is a tricky one to solve, in spite of their emergence playing such a critical role in tracking shifts in our evolution. But researchers  now think they might have cracked it.

One of the mysteries of human biological development is how the precise synchrony between molar emergence and life history came about and how it is regulated. Turning the bones and teeth of 21 species of primate into 3D models, the researchers were able to work out that the timing of our adult molars has a lot to do with the delicate balance of biomechanics in our growing skulls.  

And it's 'safety' that seems to be behind our tardy tooth growth.

"It turns out that our jaws grow very slowly, likely due to our overall slow life histories and, in combination with our short faces, delays when a mechanically safe space – or a 'sweet spot,' if you will – is available, resulting in our very late ages at molar emergence.

The back molars in primates sit just in front of two temporomandibular joints, which together form a hinge between your jaw and the skull. Unlike other joints in our body, the two pivots have to operate in perfect sync with one another. They also need to transfer a fair degree of force onto one or more points to get you biting and chewing.

In biomechanics, this three-point-process is governed by principles within something called the constrained level model. Put a tooth in the wrong spot, and the forces produced under this model could be bad news for a jaw that simply isn't big enough to cope.

For species with longer jaws, the time it takes for the skull to develop a suitable structure for teeth closest to the muscles near the hinge is relatively brief.

Humans, with our significantly flatter faces, have no such luck, needing to wait until our skulls have developed to a point that the forces put on each set of adult molars won't damage our growing jaw.

Not only does this give us a new way to evaluate dental conditions, such as impacted molars, but it could help paleontologists to better understand the evolution of our unique jaws among our hominid ancestors.

https://www.science.org/doi/10.1126/sciadv.abj0335

Part 1

The adult forms of the teeth we use to grind our food into a paste typically emerge from our gums in three stages – at around 6, 12, and 18 years of age (give or take).

Other primates get their adult molars earlier. For all our similarities in growth stages, the chimpanzee (Pan troglodytes) gets their molars at 3, 6, and 12. The yellow baboon (Papio cynocephalus) has its last adult molars out by age seven, and the rhesus macaque (Macaca mulatta) is all done by the time they're six.

One important factor constraining the timing of when teeth can appear is space. If the jaw isn't big enough for an adult-sized dental set, there's no point in squeezing them in.

Humans don't exactly have a lot of mouth space as it is, with impacted wisdom teeth a major problem for our species. But this doesn't explain why they pop up so late in our lives, or why the very back ones seem to be increasingly causing trouble.

Having an empty space for a tooth to grow doesn't make it a good idea to put one there, though. Teeth don't crunch all on their own – there's a whole lot of muscles and bone supporting them, ensuring sufficient pressure can safely tear and grind up our food.

"This study provides a powerful new lens through which the long-known linkages among dental development, skull growth and maturational profiles.

https://www.sciencealert.com/we-now-know-why-we-don-t-get-our-wisdo...

part2

Chilean scientist plans to clean up mining with 'metal eating' bacteria

Starving microorganisms capable of surviving in extreme conditions have already managed to "eat" a nail in just three days.

In Chile, a scientist is testing "metal-eating" bacteria she hopes could help clean up the country's highly-polluting mining industry.

In her laboratory in Antofagasta, an industrial town 1,100-kilometers north of Santiago, 33-year-old biotechnologist Nadac Reales has been carrying out tests with extremophiles—organisms that live in extreme environments.

Reales came up with her idea while still at university as she was conducting tests at a mining plant using microorganisms to improve the extraction of copper.

The bacteria "live in an acidic environment that is practically unaffected by relatively high concentrations of most metals.

At first the bacteria took two months to disintegrate a nail."

But when starved, they had to adapt and find a way of feeding themselves.

After two years of trials, the result was a marked increase in the speed at which the bacteria "ate," devouring a nail in just three days. s "chemical and microbiological tests" have proved the bacteria are not harmful to humans or the environment.

https://phys.org/news/2021-10-chilean-scientist-metal-bacteria.html...

**

How modern physicists think

The science of physics has strived to find the best possible explanations for understanding matter and energy in the physical world across all scales of space and time. Modern physics is filled with complex concepts and ideas that have revolutionized the way we see (and don't see) the universe. The mysteries of the physical world are increasingly being revealed by physicists who delve into non-intuitive, unseen worlds, involving the subatomic, quantum and cosmological realms. But how do the brains of advanced physicists manage this feat, of thinking about worlds that can't be experienced?

In a recently published paper in npj Science of Learning, researchers at Carnegie Mellon University have found a way to decode the brain activity associated with individual abstract scientific concepts pertaining to matter and energy, such as fermion or dark matter. They investigated the thought processes of their fellow CMU physics faculty concerning advanced physics concepts by recording their brain activity using functional Magnetic Resonance Imaging (fMRI).

This study's goal was to discover how the brain organizes highly abstract scientific concepts. An encyclopedia organizes knowledge alphabetically, a library organizes it according to something like the Dewey Decimal System, but how does the brain of a physicist do it?

The study examined whether the activation patterns evoked by the different physics concepts could be grouped in terms of concept properties. One of the most novel findings was that the physicists' brains organized the concepts into those with measureable versus immeasurable size.

Part1

For a physicist, some concepts like dark matter, neutrinos or the multiverse, their magnitude is not measureable. And in the physicists' brains, the measureable versus immeasurable concepts are organized separately.

Of course, some parts of the brain organization of the physics professors resembled the organization in physics students' brains such as concepts that had a periodic nature. Light, radio waves and gamma rays have a periodic nature but concepts like buoyancy and the multiverse do not.

part2

The neurons in the human brain have a large number of computational capabilities with various characteristics, and experience determines which of those capabilities are put to use in various possible ways in combination with other brain regions to perform particular thinking tasks. For example, every healthy brain is prepared to learn the sounds of spoken language, but an infant's experience in a particular language environment shapes which phonemes of which language are learned.

The genius of civilization has been to use these brain capabilities to develop new skills and knowledge. What makes all of this possible is the adaptability of the human brain. We can use our ancient brains to think of new concepts, which are organized along new, underlying dimensions. An example of a "new" physics dimension significant in 20^th century, post-Newtonian physics is "immeasurability" (a property of dark matter, for example) that stands in contrast to the "measurability" of classical physics concepts, (such as torque or velocity). This new dimension is present in the brains of all university physics faculty tested. The scientific advances in physics were built with the new capabilities of human brains.

Another striking finding was the large degree of commonality across physicists in how their brains represented the concepts. Even though the physicists were trained in different universities, languages and cultures, there was a similarity in brain representations. This commonality in conceptual representations arises because the brain system that automatically comes into play for processing a given type of information is the one that is inherently best suited to that processing. As an analogy, consider that the parts of one's body that come into play to perform a given task are the best suited ones: to catch a tennis ball, a closing hand automatically comes into play, rather than a pair or knees or a mouth or an armpit. Similarly, when physicists are processing information about oscillation, the brain system that comes into play is the one that would normally process rhythmic events, such as dance movements or ripples in a pond. And that is the source of the commonality across people. It is the same brain regions in everyone that are recruited to process a given concept.

So the secret of teaching ancient brains new tricks, as the advance of civilization has repeatedly done, is to empower creative thinkers to develop new understandings and inventions, by building on or repurposing the inherent information processing capabilities of the human brain. By communicating these newly developed concepts to others, they will root themselves in the same information processing capabilities of the recipients' brains as the original developers used. Mass communication and education can propogate the advances to entire populations. Thus the march of science, technology and civilization continue to be driven by the most powerful entity on Earth, the human brain.

Robert A. Mason, Reinhard A. Schumacher, Marcel Adam Just. The neuroscience of advanced scientific concepts. npj Science of Learning, 2021; 6 (1) DOI: 10.1038/s41539-021-00107-6

https://medicalxpress.com/news/2021-10-ancient-brains-modern-physic...

Part3

Myth busted: General anesthesia just as safe as spinal anesthesia after broken hip surgery

New research shows that the rates of survival, functional recovery, and post-operative delirium are similar for patients whether they underwent general anesthesia or spinal anesthesia for hip fracture surgery. This work, from the largest randomized study ever conducted to compare the two anesthesia techniques, challenges common thinking that patients who get spinal anesthesia fare better. 

The study was published in the New England Journal of Medicine and presented at Anesthesiology 2021, the annual meeting of the American Society of Anesthesiologists (ASA).

During general anesthesia, inhaled and intravenous medications are used to make patients unconscious, which often requires temporary breathing tube placement to support the lungs during surgery. For spinal anesthesia, medications are used to numb the lower part of the body through an injection into the spinal column; while patients may receive sedation for comfort, they are typically able to breathe on their own during surgery and rarely require a breathing tube.

Most recent comparisons of general anesthesia versus spinal anesthesia come from studies that hadn't randomized their populations, some of which have suggested lower rates of cognitive and medical complications with spinal. While some patients may choose spinal anesthesia with the goal of avoiding complications, others opt for general anesthesia to avoid a spinal injection or out of fears of inadequate sedation during surgery.

Researchers enrolled 1,600 patients from 46 hospitals across the United States and Canada. The patients were all at least 50 years old, had broken a hip, and had previously been able to walk. Hip fractures are particularly worrisome among older populations, like the patients in the study, since they can lead to a loss of mobility, which is associated with doubling or even tripling the risk of near-term death. What set Neuman's study apart from past work in the subject area was that it randomly divided the enrolled patients into two equal groups: Those who were set to receive general anesthesia and those who were scheduled for spinal anesthesia. Approximately 800 patients were in each group. To get a fuller picture of the potential outcomes associated with each form of anesthesia, the researchers combined subsequent patient death rates and whether they regained the ability to walk, whether on their own or with a cane or walker. By 60 days after surgery, 18.5 percent of patients assigned to spinal anesthesia had either died or become newly unable to walk versus 18 percent of patients who received general anesthesia. When looking at mortality at 60 days alone, 3.9 percent of patients who received spinal anesthesia died versus 4.1 percent who got general anesthesia. Additionally, to examine how the different forms of anesthesia factored into potential cognitive complications, the researchers also examined post-operative delirium. Roughly 21 percent of patients assigned to spinal anesthesia experienced delirium versus 20 percent of those assigned to general anesthesia. "What our study offers is reassurance that general anesthesia can represent a safe option for hip fracture surgery for many patients," said Neuman. "This is information that patients, families, and clinicians can use together to make the right choice for each patient's personalized care."

 Spinal Anesthesia versus General Anesthesia for Hip Surgery in Older Adults, New England Journal of Medicine, 2021.

https://medicalxpress.com/news/2021-10-myth-anesthesia-safe-spinal-...

Lightning strikes may trigger short-term thinning in the ozone layer

Crack! Lightning strikes are bright and loud—violent enough to shake your bones and light up the sky. Now, a new study led by the University of Colorado Boulder suggests that these powerful events may also alter the chemistry of Earth's atmosphere, even affecting Earth's all-important ozone layer.

--

Chemists develop new blueprint for enzyme involved in cancer Scientists have known for decades that a certain class of enzymes is an important player in cell biology because they frequently mutate and become major drivers of cancer. -- Chemists create chemical probe to better understand immune response A trio of chemists at Indiana University Bloomington has created a new sensor to detect chemical changes in immune cells during the breakdown of pathogens. The work could potentially contribute to the early diagnosis and treatment of infectious diseases, such as tuberculosis, that evade certain elements of the body's immune response.

When breezy, wear masks outdoors to prevent coronavirus exposure

As the highly infectious delta variant of the coronavirus continues to spread  guidelines from experts recommend even the vaccinated wear masks indoors to prevent exposure and transmission.

However, it is less clear what people should do when outside.

In Physics of Fluids, researchers from the Indian Institute of Technology Bombay found when a person coughs outdoors, wind flowing in the same direction can propagate the virus faster over longer distances than in calm conditions.

The study is significant in that it points to the increased infection risk that coughing in the same direction as the wind could bring about. Based on the results, experts recommend wearing masks outdoors, particularly in breezy conditions.

Other guidelines, such as coughing in an elbow or turning the face away while coughing, should be followed to reduce transmission when socializing outdoors.

Most studies model cough flow using puffs of air or a simple pulsating profile. But a real cough is more complicated, exhibiting turbulent flow with prominent vortical structures swirling like mini whirlpools.

To investigate these vortices, the researchers used a large eddy simulation, a numerical model in computational fluid dynamics that simulates turbulence. They modeled cough jets in breezy conditions and in calm conditions representing a typical indoor environment.

These simulations show even a light breeze of about 5 mph extends effective social distancing by around 20%, from 3-6 feet to 3.6-7.2 feet, depending on cough strength. At 9-11 mph, spreading of the virus increases in distance and duration.

The researchers found the vortices enable bigger droplets to persist in the air longer than has been typically assumed, increasing the time it takes to adequately dilute the viral load in fresh air. As the cough jet evolves and spreads, it interacts with the wind flowing in the same direction, and the bigger infected droplets become trapped in the jet's vortices instead of falling relatively quickly to the ground under gravity.

The increase in residential time of some of the larger droplets will increase the viral load transmitting through the cough jet and, therefore, the chances of infection. Overall, the study highlights increased chances of infection in the presence of even a light breeze.

"Effect of co-flow on fluid dynamics of a cough jet with implications in spread of COVID-19" Physics of Fluids, aip.scitation.org/doi/10.1063/5.0064104

https://phys.org/news/2021-10-breezy-masks-outdoors-coronavirus-exp...

Photosynthesizing algae injected into the blood vessels of tadpoles supply oxygen to their brains

Leading a double life in water and on land, frogs have many breathing techniques—through the gills, lungs, and skin—over the course of their lifetime. Now German scientists have developed another method that allows tadpoles to "breathe" by introducing algae into their bloodstream to supply oxygen. The method developed, presented October 13 in the journal iScience, provided enough oxygen to effectively rescue neurons in the brains of oxygen-deprived tadpoles.

The algae actually produced so much oxygen that they could bring the nerve cells back to life. For many people, it sounds like science fiction, but after all, it's just the right combination of biological schemes and biological principles.

This is an idea to combine plant physiology with neuroscience: harnessing the power of photosynthesis to supply nerve cells with oxygen. The idea didn't seem far-fetched. In nature, algae live harmoniously in sponges, corals, and anemones, providing them with oxygen and even nutrients. Why not in vertebrates like frogs?

To explore the possibility, researchers injected green algae, Chlamydomonas renhardtii) or cyanobacteria (Synechocystis) into tadpoles' hearts. With each heartbeat, the algae inched through blood vessels and eventually reached the brain, turning the translucent tadpole bright green. Shining light on these tadpoles prompted both algae species to pump out oxygen to nearby cells.

After distributing algae to the brain, the researchers isolated the tadpole's head and placed it in an oxygen bubble bath with essential nutrients that would preserve the functioning of the cells, allowing the team to monitor neural activity and oxygen levels. As the researchers depleted oxygen from the bath, the nerves ceased firing and fell silent. However, illuminating the tadpole head restarted the neural activity within 15 to 20 minutes, which is about two times faster than replenishing the bath with oxygen without the algae. The revived nerves also performed as well or even better than before oxygen depletion, showing that the researchers' method was quick and efficient.

The team's next step is to see whether the injected algae can survive inside living tadpoles and continue oxygen production without causing an immune response that wreaks havoc on the animals.

iScience, Özugur et al.: "Green oxygen power plants in the brain rescue neuronal activity" www.cell.com/iscience/fulltext … 2589-0042(21)01126-3 , DOI: 10.1016/j.isci.2021.103158

https://phys.org/news/2021-10-photosynthesizing-algae-blood-vessels...

After two hours, sunscreen that includes zinc oxide loses effectiveness, becomes toxic: study

Sunscreen that includes zinc oxide, a common ingredient, loses much of its effectiveness and becomes toxic after two hours of exposure to ultraviolet radiation, according to a study by scientists.

The toxicity analysis involved zebrafish, which share a remarkable similarity to humans at the molecular, genetic and cellular levels, meaning many zebrafish studies are immediately relevant to people.

Findings were published recently in Photochemical & Photobiological Sciences.

Sunscreens are important consumer products that help to reduce UV exposures and thus skin cancer, but we do not know if the use of some sunscreen formulations may have unintended toxicity because of interactions between some ingredients and UV light.

And sunscreens containing inorganic compounds like zinc oxide or titanium dioxide, that block UV rays, are being marketed more and more heavily as safe alternatives to the organic small-molecule compounds that absorb the rays.

In the experiments conducted now, zinc oxide degraded the organic mixture and caused a greater than 80% loss in organic filter protection against ultraviolet-A rays, which make up 95% of the UV radiation that reaches the Earth. Also, the zinc-oxide-induced photodegradation products caused significant increases in defects to the zebrafish we used to test toxicity. That suggests zinc oxide particles are leading to degradants whose introduction to aquatic ecosystems is environmentally hazardous.

Aurora L. Ginzburg et al, Zinc oxide-induced changes to sunscreen ingredient efficacy and toxicity under UV irradiation, Photochemical & Photobiological Sciences (2021). DOI: 10.1007/s43630-021-00101-2

https://phys.org/news/2021-10-hours-sunscreen-zinc-oxide-effectiven...

Researchers engineer microorganisms to tackle PET plastic pollution

From overflowing landfills to floating garbage islands in the oceans to microplastics in remote wilderness areas, billions of tons of discarded plastic have created a global pollution crisis.

Did you know that  every one of us has a brain "fingerprint" and that this fingerprint changes over time?

RFusion: A Robot that Finds and Retrieves Missing Objects

So-called junk DNA plays critical role in mammalian development

Nearly half of our DNA has been written off as junk, the discards of evolution: Sidelined or broken genes, viruses that got stuck in our genome and were dismembered or silenced, none of it relevant to the human organism or human evolution.

But research over the last decade has shown that some of this genetic "dark matter" does have a function, primarily in regulating the expression of host genes—a mere 2% of our total genome—that code for proteins. Biologists continue to find whether these regulatory sequences of DNA play essential or detrimental roles in the body or are merely incidental, an accident that the organism can live without.

A new study explored the function of one component of this junk DNA, transposons, which are selfish DNA sequences able to invade their host genome. The study shows that at least one family of transposons—ancient viruses that have invaded our genome by the millions—plays a critical role in viability in the mouse, and perhaps in all mammals. When the researchers knocked out a specific transposon in mice, half their mouse pups died before birth.

This is the first example of a piece of "junk DNA" being critical to survival in mammals.

In mice, this transposon regulates the proliferation of cells in the early fertilized embryo and the timing of implantation in the mother's uterus. The researchers looked in seven other mammalian species, including humans, and also found virus-derived regulatory elements linked to cell proliferation and timing of embryo implantation, suggesting that ancient viral DNA has been domesticated independently to play a crucial role in early embryonic development in all mammals.

Andrew J. Modzelewski et al, A mouse-specific retrotransposon drives a conserved Cdk2ap1 isoform essential for development, Cell (2021). DOI: 10.1016/j.cell.2021.09.021

https://phys.org/news/2021-10-so-called-junk-dna-critical-role.html...

Did the Earth tip on its side 84 million years ago?

scientists have found more evidence that Earth tips over from time to time. We know that the continents are moving slowly due to plate tectonics, but continental drift only pushes the tectonic plates past each other. It has been debated for the past few decades whether the outer, solid shell of the Earth can wobble about, or even tip over relative to the spin axis. Such a shift of Earth is called "true polar wander," but the evidence for this process has been contentious. New research published in Nature Communications, led by the Earth-Life Science Institute (ELSI) and Institute of Geology and Geophysics in Beijing, provides some of the most convincing evidence to date that such planetary tipping has indeed occurred in Earth's past.

True polar wander bears some dissecting. The Earth is a stratified ball, with a solid metal inner core, a liquid metal outer core, and a solid mantle and overriding crust at the surface which we live on. All of this is spinning like a top, once per day. Because the Earth's outer core is liquid, the solid mantle and crust are able to slide around on top of it. Relatively dense structures, such as subducting oceanic plates and massive volcanoes like Hawaii, prefer to be near the Equator, in the same way that your arms like to be out to your side when you are spinning around in an office chair.

Despite this wandering of the crust, Earth' magnetic field is generated by electrical currents in the convecting liquid Ni-Fe metal of the outer core. On long time scales, the overlying wander of the mantle and crust does not affect the core, because those overlying rock layers are transparent to Earth's magnetic field. In contrast, the convection patterns in this outer core are actually forced to dance around Earth's rotation axis, which means that the overall pattern of Earth's magnetic field is predictable, spreading out in the same fashion as iron filings lining up over a small bar magnet. Hence, these data provide excellent information about the direction of the North and South geographic poles, and the tilt gives the distance from the poles (a vertical field means you are at the pole, horizontal tells us it was on the Equator). Many rocks actually record the direction of the local magnetic field as they form, in much the same way that a magnetic tape records your music. For example, tiny crystals of the mineral magnetite produced by some bacteria actually line up like tiny compass needles, and get trapped in the sediments when the rock solidifies. This "fossil" magnetism can be used to track where the spin axis is wandering relative to the crust.

Imagine looking at Earth from space. True polar wander would look like the Earth tipping on its side, and what's actually happening is that the whole rocky shell of the planet—the solid mantle and crust—is rotating around the liquid outer core. Although scientists can measure true polar wander occurring today very precisely with satellites, geologists still debate whether large rotations of the mantle and crust have occurred in Earth's past.

part 1

Researchers  came up with a plan for settling the debate once and for all.

Researchers  came up with a plan for settling the debate once and for all.

 The international team of researchers then placed their bet that paleomagnetic data from limestones created in the Cretaceous (between ~145.5 and 65.5 million years ago) located in Italy would provide a definitive test. The magnetism of the younger rocks in the same area was studied nearly 50 years ago, and indirectly led to the discovery of the asteroid impact that killed the dinosaurs. These Italian sedimentary rocks turn out to be special and very reliable because the magnetic minerals are actually fossils of bacteria that formed chains of the mineral magnetite.

To test their hypothesis about true polar wander, paleomagnetic data with lots of redundancy are required to track the wander of the ancient location of Earth's spin axis. Prior studies, especially some claiming that true polar wander does not occur, have failed to explore enough data points according to the team.

That is one reason why it is so refreshing to see this study with its abundant and beautiful paleomagnetic data.

As the true polar wander hypothesis predicted, the Italian data indicate an ~12˚ tilt of the planet 84 million years ago. The team also found that Earth appears to have corrected itself—after tipping on its side, Earth reversed course and rotated right back, for a total excursion of nearly 25˚ of arc in about five million years. Certainly, this was a cosmic "yo-yo.

Ross N. Mitchell et al, A Late Cretaceous true polar wander oscillation, Nature Communications (2021). DOI: 10.1038/s41467-021-23803-8

https://phys.org/news/2021-10-earth-side-million-years.html?utm_sou...

Part 2

**

New understanding on how brain cells talk

Researchers have discovered that reversing the modification of molecular messages at synapses in the human brain, may contribute to reversible mental health conditions such as anxiety, and memory diseases such as dementia.

The findings are a major step in our understanding how brain cells  communicate, and could help to identify new treatments for neurological and psychiatric conditions.

Nerve cells in the human brain talk to one another at sites called synapses, where molecules are released to signal to the next cell. When people learn or remember things, this signaling is strengthened. When communication between synapses goes wrong, circuits become broken. As more circuits are lost, this changes how people can think and perform everyday tasks. This is seen in cognitive disorders, such as forms of dementia and some mental health conditions.

The function of nerve cells and synapses depends on proteins that are made using information encoded in genetic material called RNA. It is thought that RNAs are located exactly where and when they are needed for synaptic signaling because some kind of synaptic 'tag' labels the correct active synapse. Scientists have recently learnt that RNA can have a methyl group/molecule added to one of the RNA bases which 'marks' the RNA message. Such adding of methyl groups can influence proteins binding to DNA or RNA and consequently stop proteins being produced.

This new study shows that RNA marking can be reversed at synapses and hence may act as a 'synaptic tag'. The findings suggest, that if disrupted, this could cause synapses and nerve cells to malfunction by influencing the formation of toxic protein clumps.

The researchers used advanced microscopy to examine changes in marked RNAs in time and location at synapses, and a sequencing technique to characterize 'marked' RNAs in brain tissue from the hippocampus, a region of the brain very important for memory formation.

 are able to gain a new understanding of the genomic mechanisms which regulate how nerve cells communicate at synapses. These genomic mechanisms involve methyl groups being put on RNA messages and importantly taken off when a synapse is active. The implications are very important for normal brain function but also for reversible psychiatric mental conditions such as anxiety and addiction disorders and early-stage neurodegenerative diseases such as dementias.

Braulio Martinez De La Cruz et al, Modifying the m6A brain methylome by ALKBH5-mediated demethylation: a new contender for synaptic tagging, Molecular Psychiatry (2021). DOI: 10.1038/s41380-021-01282-z

https://medicalxpress.com/news/2021-10-scientists-gain-brain-cells....

More than 99.9% of studies agree: Humans caused climate change

More than 99.9% of peer-reviewed scientific papers agree that climate change is mainly caused by humans, according to a new survey of 88,125 climate-related studies.

he research updates a similar 2013 paper revealing that 97% of studies published between 1991 and 2012 supported the idea that human activities are altering Earth's climate. The current survey examines the literature published from 2012 to November 2020 to explore whether the consensus has changed.

We now are virtually certain that the consensus is well over 99% now and that it's pretty much case closed for any meaningful public conversation about the reality of human-caused climate change.

It's critical to acknowledge the principal role of greenhouse gas emissions so that we can rapidly mobilize new solutions, since we are already witnessing in real time the devastating impacts of climate related disasters on businesses, people and the economy.

Greater than 99% Consensus on Human Caused Climate Change in the Peer-Reviewed Scientific Literature, Environmental Research Letters (2021). DOI: 10.1088/1748-9326/ac2966, https://iopscience.iop.org/article/10.1088/1748-9326/ac2966

https://phys.org/news/2021-10-humans-climate.html?utm_source=nwlett...

Bacteriophages: an interesting alternative to antibiotics

Bacteriophages are viruses that kill specific types of bacteria.

Phages' ability to selectively kill bacteria also has medical doctors excited. Natural and engineered phages have been successfully used to treat bacterial infections that do not respond to antibiotics. This process, known as phage therapy, could help fight antibiotic resistance.

Researchers make hardened wooden knives that slice through steak

The sharpest knives available are made of either steel or ceramic, both of which are man-made materials that must be forged in furnaces under extreme temperatures. Now, researchers have developed a potentially more sustainable way to make sharp knives: using hardened wood. The method, presented October 20th in the journal Matter, makes wood 23 times harder, and a knife made from the material is nearly three times sharper than a stainless-steel dinner table knife. The knife cuts through a medium-well done steak easily, with similar performance to a dinner table knife.  This hardened wood  knife can be washed and reused, making it a promising alternative to steel, ceramic, and disposable plastic knives.

Teng Li, Hardened Wood as a Renewable Alternative to Steel and Plastic, Matter (2021). DOI: 10.1016/j.matt.2021.09.020. www.cell.com/matter/fulltext/S2590-2385(21)00465-3

https://phys.org/news/2021-10-hardened-wooden-knives-slice-steak.ht...

How certain proteins pass through cell walls

All these days scientists have wondered how large molecules such as proteins pass through cell walls, also known as plasma membranes, without leaving a trace. That ability is part of what makes certain drugs—including some cancer treatments and the COVID-19 vaccine—work. And it is also how bacterial toxins enter human cells and wreak havoc.

One such example is diphtheria toxin, which is produced by Corynebacterium diphtheriae and causes diphtheria, a serious and potentially fatal bacterial infection of the nose and throat. But the mechanics of how these proteins enter human cells were a scientific mystery till now.

A recent study, published in the journal ACS Chemical Biology, answers that mystery. The study identified the ways in which proteins cross a cell membrane, a finding that could create a scientific foundation for better ways of delivering drugs into cells in the future, or for treating illnesses caused by bacterial toxins.

It is almost like a magic trick, the way the membrane encapsulates these toxins.

Part 1

Researchers have known how small molecules penetrate cell membranes, typically by binding to the membrane and then diffusing through it. But they knew that proteins do not have that ability because they are too big. Until now, the most popular hypothesis was that proteins pass through small holes, known as pores, in the membrane. But previous work did not support that hypothesis.

While working on other projects, researchers noticed that some fragments of proteins, known as peptides, cross membranes by pushing against them. The peptides deformed the membrane into small circular buds. The buds then detach as small bubbles, known as vesicles, which eventually "pop," allowing the peptides to be released inside the cell. The team subsequently observed that two structurally different bacterial toxins also employed this same mechanism. This discovery led them to conclude that this budding-and-collapse mechanism is a common mechanism employed by many large biomolecules.

The team witnessed the budding-and-collapse in live cells through confocal microscopy, an imaging technique that allowed them to focus in on what was happening inside the cells, and on the cell membranes, with these specific proteins.

Researchers say the discovery could potentially open the door for new drug therapies that use this finding to manipulate the ways drugs enter a cell.

Ashweta Sahni et al, Bacterial Toxins Escape the Endosome by Inducing Vesicle Budding and Collapse, ACS Chemical Biology (2021). DOI: 10.1021/acschembio.1c00540

https://phys.org/news/2021-10-magic-proteins-cell-walls.html?utm_so...

**

A breakdown in communication -- mitochondria of diabetic patients can’t keep time

Almost all cells regulate their biological processes over a 24-hour period, otherwise called a cell’s circadian rhythm. To do so, cells use a biological clock that cycles different genes on and off throughout the day and night. Scientists already know that our metabolic health can suffer when our biological clock breaks down, due to shift work or sleep disorders, for example. However, it’s unclear how exactly the biological clock of people with type 2 diabetes differs from healthy people.

Now a team of international scientists has shown that the skeletal muscle in people with type 2 diabetes has a different circadian rhythm. They argue that this might arise because of a communication breakdown between a cell’s time keeping molecules and mitochondria, which produce chemical energy for cells.

In the study, which was published in Science Advances, the scientists first obtained skeletal muscle cells from people with type 2 diabetes and measured which genes showed cycling behavior over two days and compared them with cells from similar healthy people. They discovered that cells from people with type 2 diabetes had fewer, and some different, cycling genes.

They carried out further experiments using data generated from clinical tests in people with type 2 diabetes and mice, as well as cell-based experiments. These experiments demonstrated that mitochondria communicate with the molecules that keep time in our cells, and that this communication is disrupted in people with type 2 diabetes.

Diabetes treatments may be more effective if timed to the body clock

Some of the most widely used pharmacological treatments for type 2 diabetes affect mitochondria, meaning that they may work differently depending on the time of day they are taken. As a result, these findings highlight the importance of considering cellular rhythms when prescribing treatments for type 2 diabetes.

“Exercise and diet are regularly used treatment interventions for people with type 2 diabetes, and both of these treatments can affect the time-keeping molecules and mitochondria.

Given that disrupted sleeping patterns are known to be associated with an increased risk of developing type 2 diabetes, these findings provide evidence of how these disruptions may link to the molecular biology within cells.

https://www.science.org/doi/10.1126/sciadv.abi9654

https://www.eurekalert.org/news-releases/932152

Sound Waves Aid Brain Tumor Treatment

In a small clinical study, focusing ultrasound beams on tumors in patients’ brains helped open the blood-brain barrier to facilitate drug delivery.

Afirst-in-human trial reported in Science Translational Medicine today (October 13) demonstrates delivery of an immunotherapy drug to metastatic brain tumors with the help of focused ultrasound. The targeted low-frequency sound waves temporarily opened the normally impenetrable blood-brain barrier at the sites of tumors in stage 4 breast cancer patients, enabling drug entry. Follow up analyses indicated the procedure also led to tumor shrinkage.

It’s a really important step forward in this process of understanding how valuable focused ultrasound will be as a method to deliver drugs to the brain.

https://www.science.org/doi/10.1126/scitranslmed.abj4011?_ga=2.1653...

https://www.the-scientist.com/news-opinion/sound-waves-aid-brain-tu...

Fat cells found to play a central role in cognitive decline and neurodegeneration

Findings published this week reveal new insights into the role of fat cells in cognitive decline and neurodegeneration, according to a study that involves the oxidant amplification loop.

The research, published in iScience, shows that fat cells control the systemic response to brain function, causing impairment in memory and cognition in mice. The activation of Na,K-ATPase oxidant amplification loop affects the expression of important protein markers in fat cells as well as in the hippocampus, which can worsen brain function and lead to neurodegeneration. Targeting the fat cells to antagonize Na,K-ATPase may improve these outcomes. 

 Inducing oxidative stress through western diet increased production of inflammatory cytokines confined to adipocytes as well as altered protein markers of memory and cognition in the hippocampus. 

Western diet induces oxidant stress and adipocyte alteration through Na,K-ATPase signaling which causes systemic inflammation and affects behavioral and brain biochemical changes.

 Komal Sodhi et al, Role of Adipocyte Na,K-ATPase Oxidant Amplification Loop in Cognitive Decline and Neurodegeneration, iScience (2021). DOI: 10.1016/j.isci.2021.103262

https://medicalxpress.com/news/2021-10-fat-cells-central-role-cogni...

Scientists discover tap water produces a protective shield against microplastics

Tap water produces a natural protective shield against harmful microplastics, which can help prevent household products such as plastic kettles from releasing them. That's according to a team of scientists.
The research, published in the Chemical Engineering Journal, reveals that tap water contains trace elements and minerals, which prevent plastics from degrading in the water and releasing microplastics. Microplastics can carry a range of contaminants such as trace metals and some potentially harmful organic chemicals.
Previous studies investigating microplastics release have used forms of pure water, which only exist in laboratories and do not specifically take into account the ions and impurities found in tap water.
It is well known that plastics can degrade and release microplastics, which can get into the environment and be consumed by humans. This research shows that many items such as plastic kettles, which are repeatedly used with tap water, can develop over time a protective skin that prevents the release of microplastics entirely.
Because tap water is not 100% pure H2O—since it contains trace elements and minerals, what researchers now showed is that if you include these trace elements and minerals the degradation of plastics in tap water is completely different. Rather than the plastics falling apart, the minerals coat the plastic and prevent any kind of degradation and so the product becomes microplastic-free. For example, that dark brown color in your kettle is a good thing. It is copper oxide that forms from copper minerals in your tap water, which in turn comes from the copper pipes in your house—all these combine to give a perfect protection to the kettle.
This discovery is important because we have learned that these types of protective skins can be manufactured in the laboratory and directly applied to the plastic without having to wait for it to build up naturally.

Yunhong Shi et al, Real-world natural passivation phenomena can limit microplastic generation in water, Chemical Engineering Journal (2021). DOI: 10.1016/j.cej.2021.132466

https://phys.org/news/2021-10-scientists-shield-microplastics.html?...

Physicists Created a Supernova Reaction on Earth Using a Radioactive Beam

For the first time, physicists have been able to directly measure one of the ways exploding stars forge the heaviest elements in the Universe.

By probing an accelerated beam of radioactive ions, a team  of physicists observed the proton-capture process thought to occur in core-collapse supernovae.

Not only have scientists now seen how this happens in detail, the measurements are allowing us to better understand the production and abundances of mysterious isotopes called p-nuclei.

On the most basic level, stars can be thought of as the element factories of the Universe. Until stars were born and started smashing together nuclei in their cores, the Universe was a soup of mostly hydrogen and helium. This stellar nuclear fusion started infusing the cosmos with heavier elements, from carbon all the way up to iron for the most massive stars.

This is where core fusion hits a snag. The heat and energy required to produce iron via fusion exceeds the energy the process generates, causing the core temperature to drop, which in turn results in the star dying in a spectacular kaboom – the supernova.

This is where physicists think even heavier elements are born. The explosion is so energetic that atoms, colliding together with force, can capture components from each other. It doesn't have to be a supernova (heavy elements have been detected forming in a collision between two neutron stars) but the principle is the same. Colossal cosmic splodo boom = sufficient energy to forge elements.

Then there are the p-nuclei. These 30 or so naturally occurring isotopes of heavy elements constitute around 1 percent of the heavy elements observed in our Solar System, and their formation is a mystery.

Isotopes are forms of the same element that vary by atomic mass, usually because of a varying number of neutrons in the nucleus, while the number of protons stays the same. P-nuclei are isotopes that are neutron-deficient, but proton-rich; because they are so scarce, they are difficult to observe, which has resulted in some difficulty working out how they are forged.

The currently favored model is the gamma process, in which atoms capture loose protons during an energetic event. Since a chemical element is defined by the number of protons, this process would transform the element into the next one along in the periodic table, resulting in a neutron-poor isotope.

part 1

The observations were obtained using the Isotope Separator and Accelerator II at the TRIUMF National Laboratory in Canada to produce a beam of charged, radioactive rubidium-83 atoms. The TRIUMF-ISAC Gamma-Ray Escape Suppressed Spectrometer and Electromagnetic Mass Analyser recoil mass spectrometer were used to record and observe the processes taking place in the beam.

The results suggested the production of the p-nucleus strontium-84, the researchers said, consistent with the gamma process. They found that the thermonuclear reaction rate was lower than predicted by theoretical models, resulting in a higher production of strontium-84.

Their recalculated production rate was consistent with strontium-84 abundances observed in meteorites, the researchers said, and could help shed light on other astrophysical processes.

"The coupling of a high-resolution gamma-ray array with an advanced electrostatic separator to measure gamma process reactions represents a key milestone in the direct measurement of astrophysical processes.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.112701

https://www.sciencealert.com/scientists-have-used-a-radioactive-bea...

Part 2

This is the real ‘after life’

 Research suggests 'magnetic tunnel' surrounds our solar system

An astronomer's new  research suggests the solar system is surrounded by a magnetic tunnel that can be seen in radio waves.

Two bright structures seen on opposite sides of the sky—previously considered to be separate—are actually connected and are made of rope-like filaments. The connection forms what looks like a tunnel around our solar system.

The data results of this research have been published in The Astrophysical Journal.

If we were to look up in the sky, say researchers, we would see this tunnel-like structure in just about every direction we looked—that is, if we had eyes that could see radio light.

Called "the North Polar Spur" and "the Fan Region," astronomers have known about these two structures for decades, West says. But most scientific explanations have focused on them individually. This new work, by contrast, reveals for the first time that they are connected as a unit.

Made up of charged particles and a magnetic field, the structures are shaped like long ropes. They are located about 350 light-years away from us, and are about 1,000 light-years long.

 J. L. West et al, A Unified Model for the Fan Region and the North Polar Spur: A bundle of filaments in the Local Galaxy. arXiv:2109.14720v1 [astro-ph.GA], arxiv.org/abs/2109.14720

https://phys.org/news/2021-10-astronomer-magnetic-tunnel-solar.html...

Memories pass through many transformation stages as they are encoded

Memory, the human ability to recall things that happened in the past, is one of the topics most widely investigated by neuroscientists and psychologists. Past studies have collected extensive evidence suggesting that memory is a dynamic process, rather than a static one. In other words, instead of merely entailing the storage of events or information in the brain and their subsequent recall, memories appear to be shaped by a series of complex processes, including imagination and emotion.

Some neuroscientists have been closely examining what happens in the brain while memories are being encoded and retrieved, to better understand their neural underpinnings. They found that the neural representation patterns observed while the same memories are being encoded and retrieved are in some ways similar (i.e., there is an overlap between them), yet from the moment they are stored to when they are recalled at a later point in time, their neural representations can undergo significant transformations.

Recent findings, presented in a paper published in Science Advances, suggest that memory representations undergo several transformations while they are being encoded and consolidated in the brain.

Part 1

Combining intracranial EEG recordings with deep neural network models, researchers provided a detailed picture of the representational transformations from encoding to short-term memory maintenance and long-term memory retrieval that underlie successful episodic memory.

The results  suggest that memory representations pass through multiple stages of transformations to achieve successful long-term memory formation and recall.

Overall, the findings offer further evidence of the transformation of memory-specific neural representations throughout the encoding, short-term maintenance and long-term consolidation stages of memory.

Jing Liu et al, Transformative neural representations support long-term episodic memory, Science Advances (2021). DOI: 10.1126/sciadv.abg9715

https://medicalxpress.com/news/2021-10-memories-stages-encoded.html...

Part 2

Metaverse, the future tech 

Metaverse is internet brought to life, or at least rendered in 3D. It as a "virtual environment" you can go inside of—instead of just looking at on a screen. Essentially, it's a world of endless, interconnected virtual communities where people can meet, work and play, using virtual reality headsets, augmented reality glasses, smartphone apps or other devices.

It also will incorporate other aspects of online life such as shopping and social media. It's the next evolution of connectivity where all of those things start to come together in a seamless, doppelganger universe, so you're living your virtual life the same way you're living your physical life.

You will be able to do  things like go to a virtual concert, take a trip online, and buy and try on digital clothing. The metaverse also could be a game-changer for the work-from-home shift amid the coronavirus pandemic. Instead of seeing co-workers on a video call grid, employees could see them virtually.

For those who can afford it, users would be able, through their avatars, to flit between virtual worlds created by different companies.

A lot of the metaverse experience is going to be around being able to teleport from one experience to another.

And let me  also warn you about this ....  it will be based on using your personal data to sell targeted advertising, into the metaverse.

https://techxplore.com/news/2021-10-metaverse.html?utm_source=nwlet...

'Smart bandage' may help solve a major problem when treating chronic wounds

How can doctors make sure a dressed wound is healing without taking off the bandage? This is a conundrum, because removing a bandage can disrupt the healing process. Technology presented in a new study in open-access journal Frontiers in Physics could help.

This new 'smart bandage' contains a sensor that can very sensitively measure wound moisture levels and then transmit the data to a nearby smartphone, without requiring doctors to remove the bandage. In the future, by changing the geometry and materials in the bandage, the researchers may be able to fine tune it to suit different types of wounds. The technology could help doctors to monitor wounds more easily and successfully.

Chronic wounds can be a source of significant suffering and disability for patients who experience them. Getting such wounds to heal is tricky and there are many factors that can affect wound healing, such as temperature, glucose levels, and acidity. However, one of the most important is moisture levels. Too dry, and the tissue can become desiccated; too wet, and it can become white and wrinkly, as it does in the bath. Both these situations disrupt the healing process.

However, if a doctor wants to check the moisture levels of a wound then they need to remove the bandage, potentially damaging the delicate healing tissue. These issues have inspired this latest smart bandage, as a way to monitor wound moisture levels non-invasively. The choice of materials was a challenge, as bandages need to be biocompatible, disposable and inexpensive.

To achieve this, the researchers applied a conductive polymer called poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) onto a gauze using a technique called screen printing, and then incorporated the gauze with commercially available bandage materials. The idea is that changes in the moisture level of the wound cause a change in an electrical signal measured by the sensor.

PEDOT:PSS is an organic semiconducting polymer that can be easily deposited on several substrates as a standard ink. Researchers also incorporated a cheap, disposable and bandage-compatible RFID tag, similar to those used for clothing security tags, into the textile patch. The tag can wirelessly communicate moisture level data with a smartphone, allowing healthcare staff to know when a bandage needs to be changed.

Wireless textile moisture sensor for wound care, Frontiers in Physics, DOI: 10.3389/fphy.2021.722173

https://phys.org/news/2021-10-smart-bandage-major-problem-chronic.h...

Researchers discover a way to increase the effectiveness of antibiotics

Using immunotherapeutics to tackle the threat of superbugs

Researchers found a way to make antibiotics more effective against antibiotic-resistant bacteria—also known as 'superbugs.

Antimicrobial resistance to superbugs has been evolving and is one of the top 10 global public health threats facing humanity, according to the World Health Organization.

This new research will provide a pathway to increasing the effectiveness of antibiotics, without clinicians having to resort to risky strategies of giving patients higher doses or relying on the discovery of new types of antibiotics.

During a bacterial infection, the body uses molecules called chemoattractants to recruit neutrophils to the site of the infection. Neutrophils are immune cells with the ability to encapsulate and kill dangerous bacteria, critical to the immune response. Researchers attached a chemoattractant to an antibiotic, enabling them to enhance the recruitment of immune cells and improve their killing ability.

The findings have now been published in Nature Communications.

Antibiotic-chemoattractants enhance neutrophil clearance of Staphylococcus aureus, Nature Communications (2021). DOI: 10.1038/s41467-021-26244-5

https://phys.org/news/2021-10-effectiveness-antibiotics.html?utm_so...

“Politicians who are not trained in science should not meddle in our day-to-day business, or tell scientists what’s right or wrong.”

https://www.nature.com/articles/d41586-021-02885-w?utm_source=Natur...

"Aquatic" Jaguars

Found: an Unknown 'Ghost' Ancestor in The Human Genome

A teenage girl from over 50,000 years ago of such strange uniqueness she looked to be a 'hybrid' ancestor to modern humans that scientists had never seen before.

Only recently, researchers have uncovered evidence she wasn't alone. In a 2019 study analysing the complex mess of humanity's prehistory, scientists used artificial intelligence (AI) to identify an unknown human ancestor species that modern humans encountered – and shared dalliances with – on the long trek out of Africa millennia ago.

About 80,000 years ago, the so-called Out of Africa occurred, when part of the human population, which already consisted of modern humans, abandoned the African continent and migrated to other continents, giving rise to all the current populations.

As modern humans forged this path into the landmass of Eurasia, they forged some other things too – breeding with ancient and extinct hominids from other species.

Up until recently, these occasional sexual partners were thought to include Neanderthals and Denisovans, the latter of which were unknown until 2010.

But in this study, a third ex from long ago was isolated in Eurasian DNA, thanks to deep learning algorithms sifting through a complex mass of ancient and modern human genetic code. 

Using a statistical technique called Bayesian inference, the researchers found evidence of what they call a "third introgression" – a 'ghost' archaic population that modern humans interbred with during the African exodus.

This population is either related to the Neanderthal-Denisova clade or diverged early from the Denisova lineage.

 In 2018, another team of researchers identified evidence of what they called a "definite third interbreeding event" alongside Denisovans and Neanderthals, and a pair of papers published in early 2019 traced the timeline of how those extinct species intersected and interbred in clearer detail than ever before.

There's a lot more research to be done here yet. Applying this kind of AI analysis is a decidedly new technique in the field of human ancestry, and the known fossil evidence we're dealing with is amazingly scant.

But according to the research, what the team has found explains not only a long-forgotten process of introgression – it's a dalliance that, in its own way, informs part of who we are today. If you subtract the Neanderthal and Denisovan parts, there is still something in the genome that is highly divergent.

https://www.nature.com/articles/s41467-018-08089-7

https://www.sciencealert.com/artificial-intelligence-finds-an-unkno...

'Nanozyme' therapy prevents harmful dental plaque build-up

A growing body of evidence points to a link between iron-deficiency anemia and severe tooth decay. Whether the connection is correlative or causative is unknown, though both conditions are associated with poor diets and are more common in people living in impoverished environments and with underlying medical conditions.

Now, new research suggests that an FDA-approved therapy for iron-deficiency anemia also holds promise for treating, preventing, and even diagnosing dental decay. The therapeutic, a combination of an iron-oxide nanoparticle-containing solution called ferumoxytol and hydrogen peroxide, was applied to real tooth enamel placed in a denture-like appliance and worn by the study subjects.

The study, published in the journal Nano Letters, found that a twice daily application of ferumoxytol, which activated hydrogen peroxide contained in a follow-up rinse, significantly reduced the buildup of harmful dental plaque and had a targeted effect on the bacteria largely responsible for tooth decay. These types of nanoparticles with enzyme-like properties are sometimes known as "nanozymes" and are increasingly being explored for their potential in biomedical and environmental applications.

Researchers found that this approach is both precise and effective. It disrupts biofilms, particularly those formed by Streptococcus mutans, which cause caries, and it also reduced the extent of enamel decay. 

Yuan Liu et al, Ferumoxytol Nanoparticles Target Biofilms Causing Tooth Decay in the Human Mouth, Nano Letters (2021). DOI: 10.1021/acs.nanolett.1c02702

https://phys.org/news/2021-10-nanozyme-therapy-dental-plaque-build-...