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-...

 Lack of sleep affects your walk, new study finds

Good sleep can be hard to come by. But a new study finds that if you can make up for lost sleep, even for just a few weekend hours, the extra zzz's could help reduce fatigue-induced clumsiness, at least in how you walk.

There's plenty of evidence to show sleep, and how much we get of it, can affect how well we do on cognitive tasks such as solving a math problem, holding a conversation, or even reading this article. Less explored is the question of whether sleep influences the way we walk or carry out other activities that are assumed to be less mentally taxing.

The new study, by researchers at MIT and the University of São Paulo in Brazil, reports that walking—and specifically, how well we can control our stride, or gait—can indeed be affected by lack of sleep.

In experiments with student volunteers, the team found that overall, the less sleep students got, the less control they had when walking during a tread-mill test. For students who pulled an all-nighter before the test, this gait control plummeted even further.

Interestingly, for those who didn't stay up all night before the test, but who generally had less-than-ideal sleep during the week, those who slept in on weekends performed better than those who didn't.

Sleep deprivation affects gait control, Scientific Reports (2021). DOI: 10.1038/s41598-021-00705-9

https://medicalxpress.com/news/2021-10-feet-lack-affects.html?utm_s...

Underwater Drone Flies AND Swims

This device could usher in GPS-free navigation

A new era of navigation.

For over a year, the avocado-sized vacuum chamber has contained a cloud of atoms at the right conditions for precise navigational measurements. It is the first device that is small, energy-efficient and reliable enough to potentially move quantum sensors — sensors that use quantum mechanics to outperform conventional technologies — from the lab into commercial use, said Sandia National Laboratories scientist Peter Schwindt.

Sandia developed the chamber as a core technology for future navigation systems that don’t rely on GPS satellite.

Countless devices around the world use GPS for wayfinding. It’s possible because atomic clocks, which are known for extremely accurate timekeeping, hold the network of satellites perfectly in sync.

But GPS signals can be jammed or spoofed, potentially disabling navigation systems on commercial and military vehicles alike, Schwindt said.

So instead of relying on satellites,  future vehicles might keep track of their own position. They could do that with on-board devices as accurate as atomic clocks, but that measure acceleration and rotation by shining lasers into small clouds of rubidium gas like this one.

Atomic accelerometers and gyroscopes already exist, but they’re too bulky and power-hungry to use in an airplane’s navigation system. That’s because they need a large vacuum system to work, one that needs thousands of volts of electricity.

“Quantum sensors are a growing field, and there are lots of applications you can demonstrate in the lab. But when you move it into the real world there are lots of problems you have to solve. Two are making the sensor compact and rugged. The physics takes place all in a cubic centimeter (0.06 cubic inches) of volume, so anything larger than that is wasted space.”

part1

 quantum sensing can work without a high-powered vacuum system. This shrinks the package to a practical size without sacrificing reliability.

Instead of a powered vacuum pump, which whisks away molecules that leak in and wreck measurements, a pair of devices called getters use chemical reactions to bind intruders. The getters are each about the size of a pencil eraser so they can be tucked inside two narrow tubes sticking out of the titanium package. They also work without a power source.

To further keep out contaminants, Schwindt partnered with Sandia materials scientists to build the chamber out of titanium and sapphire. These materials are especially good at blocking out gasses like helium, which can squeeze through stainless steel and Pyrex glass. Funding was provided by Sandia’s Laboratory Directed Research and Development program.

Construction took sophisticated fabrication techniques that Sandia has honed to bond advanced materials for nuclear weapons components. And like a nuclear weapon, the titanium chamber must work reliably for years.

The Sandia team is continuing to monitor the device. Their goal is to keep it sealed and operational for five years, an important milestone toward showing the technology is ready to be fielded. In the meantime, they’re exploring ways to streamline manufacturing.

https://www.eurekalert.org/news-releases/932743

part2

Atoms .... see them!

Study confirms mistaken identity may explain why sharks bite humans

World-first research testing a simulated 'shark vision' model on swimming patterns of humans, seals and sea-lions, confirms theories that when great white sharks bite humans, it may be a case of mistaken identity.

Great white sharks are also called white sharks—and together with bull and tiger sharks, they account for by far the most bites on humans.

Researchers found that surfers, swimmers and pinnipeds (seals and sea-lions) on the surface of the ocean will look the same to a white shark looking up from below, because these sharks can't see fine details or colours.

Sharks use a range of sensory cues to distinguish between different objects and zero in on their food, and these differ in sensitivity between shark species. White sharks are highly visual—and juveniles are more dangerous to humans than are older, larger white sharks which have better vision.

When white sharks reach around 2.5 meters in length, their jaws begin to harden so they can take on bigger prey like seals. They need to develop a search image for these prey items and combine that with other sensory information; it's a learning process that could be prone to mistakes. Understanding why shark bites occur can help us find ways to prevent them, while keeping both humans and sharks safer.

 Laura A. Ryan et al, A shark's eye view: testing the 'mistaken identity theory' behind shark bites on humans, Journal of The Royal Society Interface (2021). DOI: 10.1098/rsif.2021.0533

https://phys.org/news/2021-10-mistaken-identity-sharks-humans.html?...

Researchers create mirror-image peptides that can neutralize SARS-CoV-2

Researchers at the University of Toronto have created chemical compounds that can neutralize SARS-CoV-2 and several of its variants.

In a recent paper published in the Journal of Medicinal Chemistry, the researchers report the creation of D-peptides that neutralize the virus and stop infection of cultured human cells.

Known as mirror-image peptides, the compounds have chemical properties that make them suitable for the development of low-cost antiviral therapeutics.

A big advantage of mirror-image peptides is their long stability and that they are relatively cheap to produce.

Peptides are similar to proteins in that they are composed of the same amino-acids building blocks. But they are smaller than protein molecules. They can be designed to bind virtually any molecular target and with a greater specificity than small-molecule drugs, reducing the risk of side effects. In this way, peptides are similar to antibodies but are at least 100 times cheaper to produce thanks to their small size. The combination of low cost and easy scaling of manufacturing makes peptides attractive, particularly for low-income countries.

But there's a caveat. In the body, peptides are rapidly degraded by the enzymes that have evolved to stamp out harmful versions produced by bacteria and other pathogens. But science has found a solution in mirror-image peptides that are resistant to degradation.

For reasons that remain unclear, all naturally occurring amino acids exist in a left-handed configuration, as defined by the direction in which they rotate. Consequently, all proteins and peptides are also left-handed—and known as L-peptides. These mirror-image molecules are manufactured from synthetic D-amino acids strung together in the same way as their left-handed counterparts.  They can be engineered to bind the same targets with undiminished specificity. The main difference is that their unusual geometry makes them resistant to enzymes in the bloodstream that break down normal L-peptides. 

Pedro A. Valiente et al, Computational Design of Potent D-Peptide Inhibitors of SARS-CoV-2, Journal of Medicinal Chemistry (2021). DOI: 10.1021/acs.jmedchem.1c00655

https://phys.org/news/2021-10-mirror-image-peptides-neutralize-sars...

**

The Pupil in Your Eye Can Perceive Numerical Information, Not Just Light

You might know that the size of the pupils in our eyes changes depending on how well lit our environment is, but there's more to the story: Scientists have now discovered that the pupil also shifts in size depending on how many objects we're observing.

The more objects in a scene, the bigger the pupil grows, as if to better accommodate everything that it has to look at. This "perceived numerosity" is a simple and automatic reflex, the new research shows.

In a new study, researchers observed the pupil sizes of 16 participants while they looked at pictures of dots. In some of the pictures, the dots were linked together in dumbbell shapes – creating the illusion that there were fewer objects – and pupil size then shrank. This result shows that numerical information is intrinsically related to perception.

As for where this reaction comes from, it's likely to be linked to the need for survival – most species are thought to have a dedicated 'number sense' that enables them to spot enemies in the wild, find food, get back home, and more besides.

When it comes to humans, being able to weigh up numbers is something that seems to appear as soon as a few hours after birth – even if you're terrible at math, you have a built-in aptitude for judging numerosity, and it appears the dilation of our pupils is part of a response to that. When we look around, we spontaneously perceive the form, size, movement and color of a scene. Equally spontaneously, we perceive the number of items before us. This ability, shared with most other animals, is an evolutionary fundamental: it reveals immediately important quantities, such as how many apples there are on the tree, or how many enemies are attacking.

And there's lots more to explore here as well. Our eyes seem to be more sensitive to the number of items we're looking at rather than how they're spaced or arranged, which is another reaction that can be analyzed in future studies.

https://www.nature.com/articles/s41467-021-26261-4

https://www.sciencealert.com/pupil-size-changes-depending-on-how-ma...

Technology to produce unbreakable screens

Cracked phone screens could become a thing of the past thanks to breakthrough research.

A team of researchers  have unlocked the technology to produce next-generation composite glass for lighting LEDs and smartphone, television and computer screens.

The findings will enable the manufacture of glass screens that are not only unbreakable but also deliver crystal clear image quality.

The discovery was a huge step forward in perovskite nanocrystal technology as previously, researchers were only able to produce this technology in the bone-dry atmosphere of a laboratory setting. The emitting materials are made from nanocrystals, called lead-halide perovskites.

They can harvest sunlight and concert it into renewable electricity—playing a vital role in low-cost and high-efficiency new generation solar cells and many promising applications like lighting. Unfortunately, these nanocrystals are extremely sensitive to light, heat, air and water—even water vapor in our air would kill the current devices in a matter of minutes. But this team of chemical engineers and material scientists has developed a process to wrap or bind the nanocrystals in porous glass. This process is key to stabilizing the materials, enhancing its efficiency and inhibits the toxic lead ions from leaching out from the materials.

At present QLED or quantum dot light-emitting diode screens are considered the top performer for image display and performance. This research will enable us to improve on this nanocrystal technology by offering stunning picture quality and strength.

Jingwei Hou et al, Liquid-phase sintering of lead halide perovskites and metal-organic framework glasses, Science (2021). DOI: 10.1126/science.abf4460

https://phys.org/news/2021-10-technology-unbreakable-screens.html?u...

10 UNESCO forests emit more CO2 than they soak up

Sites containing some of the world's most treasured forests, including the Yosemite National Park and Indonesia's Sumatra rainforest, have been emitting more heat-trapping carbon dioxide than they have absorbed in recent years, a U.N.-backed report said.

According to the report released Thursday, factors like logging, wildfires and clearance of land for agriculture are to blame. The excess carbon turns up from just 10 of 257 forests classified among UNESCO World Heritage sites.

The 10 sites that were net sources of carbon from 2001 to 2020 were the Tropical Rainforest in Sumatra; the Río Platano Biosphere Reserve in Honduras; Grand Canyon National Park and Yosemite National Park in the United States: Waterton Glacier International Peace Park in Canada and the U.S.; the Barberton Makhonjwa Mountains in South Africa; Kinabalu Park in Malaysia; the Uvs Nuur Basin in Russia and Mongolia; the Greater Blue Mountains area of Australia; and Morne Trois Pitons National Park in Dominica.

The Switzerland-based International Union for Conservation of Nature and UNESCO, the U.N.'s cultural and educational agency, said their report provides the first-ever assessment of greenhouse gases produced and absorbed in UNESCO-listed forests. The study was based on information collected through on-site monitoring and from satellites.

The study adds to growing signs that human activities and the fallout from climate change —which scientists say has made weather extremes like drought and wildfires more likely—have transformed some natural carbon sinks that suck up CO₂ from the air into net sources of it over the last two decades.

The report's finding that even some of the most iconic and best protected forests, such as those found in World Heritage sites, can actually contribute to climate change is alarming.

This is because of cutting trees and clearing forests , which produce CO2 and  also largely due to a bout of devastating wildfires in these areas in recent years.

https://phys.org/news/2021-10-unesco-forests-emit-co2.html?utm_sour...

Study finds California condors can have 'virgin births'

 Condors can have "'virgin births," according to a study released recently. 

Researchers with the San Diego Zoo Wildlife Alliance said genetic testing confirmed that two male chicks hatched in 2001 and 2009 from unfertilized eggs were related to their mothers. Neither was related to a male.

The study was published Thursday in the the Journal of Heredity. It's the first report of asexual reproduction in California condors, although parthenogenesis can occur in other species ranging from sharks to honey bees to Komodo dragons.

But in birds, it usually only occurs when females don't have access to males. In this case, each mother condor had previously bred with males, producing 34 chicks, and each was housed with a fertile male at the time they produced the eggs through parthenogenesis.

The researchers said they believe it is the first case of asexual reproduction in any avian species where the female had access to a mate.

These findings now raise questions about whether this might occur undetected in other species too. 

OUP accepted manuscript, Journal Of Heredity (2021). DOI: 10.1093/jhered/esab052

https://phys.org/news/2021-10-california-condors-virgin-births.html...

Study finds the SARS-CoV-2 virus can infect the inner ear

Many COVID-19 patients have reported symptoms affecting the ears, including hearing loss and tinnitus. Dizziness and balance problems can also occur, suggesting that the SARS-CoV-2 virus may be able to infect the inner ear.

A new study from MIT and Massachusetts Eye and Ear provides evidence that the virus can indeed infect cells of the inner ear, including hair cells, which are critical for both hearing and balance. The researchers also found that the pattern of infection seen in human inner ear tissue is consistent with the symptoms seen in a study of 10 COVID-19 patients who reported a variety of ear-related symptoms.

The researchers used novel cellular models of the human inner ear that they developed, as well as hard-to-obtain adult human inner ear tissue, for their studies. The limited availability of such tissue has hindered previous studies of COVID-19 and other viruses that can cause hearing loss.

Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction, Communications Medicine, DOI: 10.1038/s43856-021-00044-w

https://medicalxpress.com/news/2021-10-sars-cov-virus-infect-ear.ht...

Researchers invent chemical reaction that could accelerate drug discovery

Medicines come from chemical reactions, and better chemical reactions lead to better medicines.

Yet, the most popular reaction used in drug discovery, called the amide coupling, makes an inherently unstable amide bond. Because the body excels at metabolizing medication, one of the most important and difficult goals of drug research is to invent metabolically stable molecules, so we can take one pill a day instead of every 15 minutes.

To that end, researchers at the University of Michigan College of Pharmacy hacked the popular amide coupling to produce a carbon-carbon bond instead of an amide. The carbon-carbon bond is the most prevalent bond arrangement in nature and in synthetic drugs, and it's also typically more stable than the amide bond, the study appears online in the Angewandte Chemie International Edition.

The discovery of the carbon-carbon bond-forming reaction opens the door to more stable medicines, and is particularly applicable to biological probes and new medical imaging agents.

The common amide bond is formed by coupling an amine and a carboxylic acid. To form a carbon-carbon bond, researchers identified a catalyst that deaminates the amine and decarboxylates the carboxylic acid, forming a carbon-carbon bond in the process.

Joining an amine and a  carboxylic acid to make a carbon-carbon bond is also advantageous because these reagents are available in the highest diversity, and are typically less expensive than other raw ingredients that could be used to make a carbon-carbon bond.

Timothy Cernak et al, The Formal Cross‐Coupling of Amines and Carboxylic Acids to Form sp3–sp3 Carbon–Carbon Bonds, Angewandte Chemie International Edition (2021). DOI: 10.1002/anie.202112454

https://phys.org/news/2021-10-chemical-reaction-drug-discovery.html...

What is net-zero?

The search for people who never get COVID

Scientists have launched a global hunt for people who are genetically resistant to infection with SARS-CoV-2. They hope that identifying the genes protecting these individuals could lead to the development of virus-blocking drugs that not only protect people from COVID-19, but also prevent them from passing on the infection.

Vascular disease in COVID-19 is not caused by viral infection of blood vessels

The SARS-CoV-2 virus does not infect blood vessels, despite the high risk of blood clots to COVID-19 patients, researchers have found.

The researchers found that the cardiovascular complications of COVID-19 are triggered by inflammation caused by infected airway cells. At least 40 per cent of patients that are hospitalised with COVID-19 are at high risk of blood clots, and anti-coagulation therapies are now being routinely used.

There have been many studies attempting to prove whether the virus is infecting cells of the inner blood vessel wall or not.

By conducting the experiments using real, infectious virus rather than fragments of the virus’s spike protein,researchers now can definitively say it is not.

The researchers used UQ’s sophisticated microscopy facilities to track where the virus travelled in the cells and visualise how blood vessels respond to the live virus.
The body’s inflammatory response had a big effect on the cardiovascular system because they work together to fight infection – the blood delivers the immune cells to the site of infection and makes blood clots if the blood vessel is damaged.

When our immune system works well, it clears the virus from our bodies. But sometimes it goes into overdrive and we get an overblown inflammatory response causing complications –in the case of COVID-19, this is often blood clots, when there shouldn’t be any.

Knowing that it is inflammation causing these cardiovascular complications arising from COVID-19 rather than the virus itself will help us develop the right treatments, and a better understanding of how and why these complications arise.

https://onlinelibrary.wiley.com/doi/10.1002/cti2.1350

https://www.uq.edu.au/news/article/2021/10/vascular-disease-covid-1...

https://researchnews.cc/news/9726/Vascular-disease-in-COVID-19-is-n...

Experts name new species of human ancestor

An international team of researchers, led by University of Winnipeg palaeoanthropologist Dr. Mirjana Roksandic, has announced the naming of a new species of human ancestor, Homo bodoensis. This species lived in Africa during the Middle Pleistocene, around half a million years ago, and was the direct ancestor of modern humans.

The Middle Pleistocene (now renamed Chibanian and dated to 774,000–129,000 years ago) is important because it saw the rise of our own species (Homo sapiens) in Africa, our closest relatives, and the Neanderthals (Homo neanderthalensis) in Europe.

However, human evolution during this age is poorly understood, a problem which paleoanthropologists call "the muddle in the middle." The announcement of Homo bodoensis hopes to bring some clarity to this puzzling, but important chapter in human evolution.

 Resolving the "muddle in the middle": The case for Homo bodoensis sp. nov, Evolutionary Anthropology Issues News and Reviews, DOI: 10.1002/EVAN.21929

https://phys.org/news/2021-10-experts-species-human-ancestor.html?u...

Using immunotherapeutics to tackle the threat of superbugs

Recognizing familiar faces relies on a neural code shared across brains

The ability to recognize familiar faces is fundamental to social interaction. This process provides visual information and activates social and personal knowledge about a person who is familiar. But how the brain processes this information across participants has long been a question. Distinct information about familiar faces is encoded in a neural code that is shared across brains, according to a new study published in the Proceedings of the National Academy of Sciences.

Within visual processing areas, researchers found that information about personally familiar and visually familiar faces is shared across the brains of people who have the same friends and acquaintances. The surprising part of these findings was that the shared information about personally familiar faces also extends to areas that are non-visual and important for social processing, suggesting that there is shared social information across brains.

In decoding personally familiar identities, the findings demonstrated that there was much more shared information across the brains of the participants. There was high decoding accuracy in four other areas outside of the visual system: the dorsal medial prefrontal cortex, which is known to be involved in social processing (processing other people's intentions and traits); the precuneus, an area which has been shown to be more active when processing personally familiar faces; the insula, which is known to be involved in emotional processing; and the temporal parietal junction, which plays an important role in social cognition and in representing the mental states of others (also known as the "theory of the mind").

This shared conceptual space for the personal knowledge of others allows us to communicate with people that we know in common.

Shared neural codes for visual and semantic information about familiar faces in a common representational space, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2110474118.

Part 1

For the study, the research team applied a method called hyperalignment, which creates a common representational space for understanding how brain activity is similar between participants. The team used data obtained from three fMRI tasks with 14 graduate students who had known each other for at least two years. In two of the tasks, participants were presented with images of four other personally familiar graduate students and four other visually familiar persons, who were previously unknown. In the third task, participants watched parts of The Grand Budapest Hotel. The movie data, which is publicly available, was used to apply hyperalignment and align participants' brain responses into a common representational space. This allowed the researchers to use machine learning classifiers to predict what stimuli a participant was looking at based on the brain activity of the other participants.

The results showed that the identity of visually familiar and personally familiar faces was decoded with accuracy across the brain in areas that are mostly involved in visual processing of faces. Outside of the visual areas however, there was not a lot of decoding. For visually familiar identities, participants only knew what the stimuli looked like; they did not know who these people were or have any other information about them.

https://medicalxpress.com/news/2021-11-familiar-neural-code-brains....

Part 2

 Ocean plastics could be converted to ship fuel

A team of researchers think that the plastic amassing in floating islands in the oceans could be used to power the ships that are sent to clean them up. In their paper published in Proceedings of the National Academy of Sciences, the group describes how ocean plastics could be converted to ship fuel.

Prior research has shown that millions of tons of plastics enter the ocean each year—some of it is ground into fragments and disperses, and some of it winds up in colossal garbage patches floating in remote parts of the ocean. Because of the danger that such plastics present to ocean life, some environmentalists have begun cleanup operations. Such operations typically involve sending a ship to a garbage patch, collecting as much as the ship will hold and then bringing it back to port for processing. In this new effort, the researchers suggest it would be far more efficient and greener to turn the plastic into fuel for both a processing machine and for uninterrupted operation of the ships.

The researchers note that the plastic in a garbage dump could be converted to a type of oil via hydrothermal liquefaction (HTL). In this process, the plastic is heated to 300–550 degrees Celsius at pressures 250 to 300 times that of sea-level conditions. The researchers have calculated that a ship carrying an HTL converter would be capable of producing enough oil to run the HTL converter and the ship's engine. Under their scenario, plastic collection booms would be permanently stationed at multiple sites around a large garbage patch, able to load the plastic it collects onto ships.

--

The researchers acknowledge that burning the oil produced would release carbon into the atmosphere, but note that the amount emitted would still be less than that emitted by a ship burning conventional oil making trips back and forth to ports. They also note that HTL does produce a small amount of solid waste, which would have to be taken back to port, likely every few months—excess fuel produced by the HTL could be used for these trips.

 Elizabeth R. Belden et al, Thermodynamic feasibility of shipboard conversion of marine plastics to blue diesel for self-powered ocean cleanup, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2107250118

https://techxplore.com/news/2021-11-ocean-plastic-power-cleanup-shi...

Change in the Arctic and how it affects the whole world

Researchers discover new type of nerve cell in the retina

Scientists have discovered a new type of nerve cell, or neuron, in the retina.

In the central nervous system, a complex circuitry of neurons communicate with each other to relay sensory and motor information; so-called interneurons serve as intermediaries in the chain of communication. Publishing in the Proceedings of the National Academy of Sciences of the United States of America, a research team  identifies a previously unknown type of interneuron in the mammalian retina.

The discovery marks a notable development for the field as scientists work toward a better understanding of the central nervous system by identifying all classes of neurons and their connections.

Based on its morphology, physiology, and genetic properties, this cell doesn't fit into the five classes of retinal neurons first identified more than 100 years ago. Researchers, therefore, propose they might belong to a new retinal neuron class by themselves.

The research team named their discovery the Campana cell after its shape, which resembles a hand bell. Campana cells relay visual signals from both types of light-sensing rod and cone photoreceptors in the retina, but their precise purpose is the subject of ongoing research. Experiments showed Campana cells remain activated for an unusually long time—as long as 30 seconds—in response to a 10 millisecond light flash stimulation.

In the brain, persistent firing cells are believed to be involved in memory and learning. Since Campana cells have a similar behavior, we theorize they could play a role in prompting a temporal 'memory' of a recent stimulation.

Brent K. Young, Charu Ramakrishnan, Tushar Ganjawala, Ping Wang, Karl Deisseroth, Ning Tian. An uncommon neuronal class conveys visual signals from rods and cones to retinal ganglion cells. Proceedings of the National Academy of Sciences, 2021; 118 (44): e2104884118 DOI: 10.1073/pnas.2104884118

https://researchnews.cc/news/9777/Researchers-discover-new-type-of-...

COVID-19 virus test sensitivity follows the body’s circadian rhythm