Novel magnetic spray transforms objects into millirobots for biomedical applications

The Health Risks of Space: Scientists Just Unveiled The Biggest Study Yet

Space is a hostile place. We may have developed the technology to launch astronauts into orbit and get them home safely, but scientists are still figuring out how space travel affects human health, especially over the long haul. 

That's essential before any planned missions to Mars go ahead, to assure the health and safety of the astronauts aboard those momentous flights.

We already know from astronaut studies – perhaps most famously, NASA's Twins Study co-starring identical twins Scott and Mark Kelly – that extended space time affects blood flow to the brain, alters the gut microbiome, increases inflammation and causes blurred vision, brittle bones, and muscle wasting. 

Mouse studies simulating spaceflight have also suggested that heading into space ages the immune system and damages the brain.

Now, in a huge collective effort, scientists have published a giant trove of almost 30 papers investigating the health risks associated with space travel.

The collection amounts to the largest set of space biology data ever produced, and features some hefty analyses of observations from space-going flies, worms, mice, and of course, astronauts.  Some of the results reaffirm what we knew about space-related health problems, while other studies provide new insights, clarify previous results, or have found ways to improve future experiments.

The health perils of space travel start with the G forces felt by astronauts on lift-off, and continue with the exposure to hazardous space radiation and microgravity while in space.

On the treacherous journey to Mars, for example, astronauts will go far beyond Earth's protective magnetosphere and be exposed to cosmic radiation during the significant stretch of time it will take for them to venture out to our nearest planetary neighbour and return. Many of the studies published in this collection have pooled or re-analysed data from previous experiments made available to researchers through open-access data portals 

https://www.cell.com/c/the-biology-of-spaceflight

https://www.sciencealert.com/a-mass-dump-of-30-new-papers-explores-...

Is Origin Of Life All About Energy?

What is the origin of life? It’s a question scientists, philosophers and theologians have debated for centuries. If you believe one widely accepted scientific theory, life on Earth was one big happy accident, overcoming the astronomical odds against it. But a new notion is rocking the scientific world, claiming that's not the case at all.

Thermodynamics of evolution and Darwinism According to thermodynamic theory, evolution (1978) is a spontaneous process that develops within living systems in accordance with the second law of thermodynamics. However, this process takes place against the background of non-spontaneous changes in the same systems - processes that are initiated by the environment. These non-spontaneous processes cannot be predicted by thermodynamics. Thus, Darwinism, the physical foundation of which is hierarchical thermodynamics, only partially determines the direction of the evolution of living beings. Evolution tends to develop according to the second law of thermodynamics, when the environment has relatively little effect on this evolutionary development. In the event of abrupt changes in the environment, evolutionary changes are unpredictable. Thermodynamics sets the trend of evolutionary changes only at certain stages of evolution. In this regard, in general, the theory of Darwinism, as a theory that establishes the direction of evolution, has limited application. This explanation does not require the use of the concept of artificial intelligence. The presented considerations make it possible to assert that life in the universe is characterized by practically infinite biological diversity, including the diversity of civilizations, in appropriate conditions within the framework of thermodynamics. Gladyshev G.P. J Thermodyn Catal, 2017, 8: 2 DOI: 10,4172 / 2157-7544.100018, Life - A Complex Spontaneous Process Takes Place against the Background of Non-Spontaneous Processes Initiated by the Environment P. S. It is interesting to note that in the work “On Growth and Form,” D’Arcy Wentworth Thompson argued that organisms are shaped less by adaptive evolutionary function and more by deep mathematical laws. To understand his argument, you need only look at the combs made by bees. One gets the impression that D’Arcy Wentworth Thompson argued that mathematical laws (thermodynamics) and environment (adaptation) determine evolution.

Virtual reality helps measure vulnerability to stress

Sestrin makes fruit flies live longer

Reduced food intake, known as dietary restriction, leads to a longer lifespan in many animals and can improve health in humans. However, the molecular mechanisms underlying the positive effects of dietary restriction are still unclear. Researchers from the Max Planck Institute for Biology of Ageing have now found one possible explanation in fruit flies: they identified a protein named Sestrin that mediates the beneficial effects of dietary restriction. By increasing the amount of Sestrin in flies, researchers were able to extend their lifespan and at the same time these flies were protected against the lifespan-shortening effects of a protein-rich diet. The researchers could further show that Sestrin plays a key role in stem cells in the fly gut thereby improving the health of the fly. The health benefits of dietary restriction have long been known. Recently, it has become clear that restriction of certain food components.

The results in flies revealed Sestrin as a novel potential anti-ageing factor.

https://www.age.mpg.de/public-relations/news/detail/positive-effect...

https://researchnews.cc/news/3854/Sestrin-makes-fruit-flies-live-lo...

Adaptive structures cut down buildings and infrastructures carbon footprint

Fingerprints' moisture-regulating mechanism strengthens human touch: study

Human fingerprints have a self-regulating moisture mechanism that not only helps us to avoid dropping things, but could help scientists to develop better prosthetic limbs, robotic equipment and virtual reality environments, a new study reveals.

Primates—including humans, monkeys and apes—have evolved epidermal ridges on their hands and feet with a higher density of sweat glands than elsewhere on their bodies. This allows precise regulation of skin moisture to give greater levels of grip when manipulating objects.

Fingerprints help to increase friction when in contact with smooth surfaces, boost grip on rough surfaces and enhance tactile sensitivity. Their moisture-regulating mechanism ensures the best possible hydration of the skin's keratin layer to maximize friction.

Primates have evolved epidermal ridges on their hands and feet. During contact with solid objects, fingerprint ridges are important for grip and precision manipulation. They regulate moisture levels from external sources or the sweat pores so that friction is maximized and we avoid 'catastrophic' slip and keep hold of objects. Understanding the influence of finger pad friction will help us to develop more realistic tactile sensors—for example, applications in robotics and prosthetics and haptic feedback systems for touch screens and virtual reality environments.

Ultrasonic lubrication is commonly used in touch screen displays that provide sensory 'haptic' feedback, but its effectiveness is reduced when a user has dry compared with moist finger pads. Moreover, being able to distinguish between fine-textured surfaces, such as textiles, by touch relies on the induced lateral vibrations but the absence of sliding friction inhibits our ability to identify what we are actually touching.

Fingerprints are unique to primates and koalas—appearing to have the dual function of enhancing evaporation of excess moisture whist providing a reservoir of moisture at their bases that enables grip to be maximized.

The researchers have discovered that, when finger pads are in contact with impermeable surfaces, the sweat from pores in the ridges makes the skin softer and thus dramatically increases friction. However, the resulting increase in the compliance of the ridges causes the sweat pores eventually to become blocked and hence prevents excessive moisture that would reduce our ability to grip objects.

Using hi-tech laser-based imaging technology, the scientists found that moisture regulation could be explained by the combination of this sweat pore blocking and the accelerated evaporation of excessive moisture from external wetting as a result of the specific cross-sectional shape of the epidermal furrows when in contact with an object.

These two functions result in maintaining the optimum amount of moisture in the fingerprint ridges that maximizes friction whether the finger pad is initially wet or dry.

Seoung-Mok Yum el al., "Fingerprint ridges allow primates to regulate grip," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2001055117

https://phys.org/news/2020-11-fingerprints-moisture-regulating-mech...

Scientists develop 'more accurate, fast Covid test' method to detect single virus particles

How Bats Can Transmit Viruses | Virus Hunters

New device offers faster way to detect antibiotic-resistant bacteria

Bacterial infections have become one of the biggest health problems worldwide, and a recent study shows that COVID-19 patients have a much greater chance of acquiring secondary bacterial infections, which significantly increases the mortality rate.

Combatting the infections is no easy task, though. When antibiotics are carelessly and excessively prescribed, that leads to the rapid emergence and spread of antibiotic-resistant genes in bacteria—creating an even larger problem. 

One factor slowing down the fight against antibiotic-resistant bacteria is the amount of time needed to test for it. The conventional method uses extracted bacteria from a patient and compares lab cultures grown with and without antibiotics, but results can take one to two days, increasing the mortality rate, the length of hospital stay and overall cost of care.

To effectively treat the infections, we need to select the right antibiotics with the exact dose for the appropriate duration. There's a need to develop an antibiotic-susceptibility testing method and offer effective guidelines to treat these infections.

A new technique 's developed now that relies on the same principles as the batteries: Bacterial electron transfer, a chemical process that certain microorganisms use for growth, overall cell maintenance and information exchange with surrounding microorganisms. Researchers leverage this biochemical event for a new technique to assess the antibiotic effectiveness against bacteria without monitoring the whole bacterial growth.

A medical team would extract a sample from a patient, inoculate the bacteria with various antibiotics over a few hours and then measure the electron transfer rate. A lower rate would mean that the antibiotics are working.

"The hypothesis is that the antiviral exposure could cause sufficient inhibition to the bacterial electron transfer, so the readout by the device would be sensitive enough to show small variations in the electrical output caused by changes in antibiotic effectiveness. The device could provide results about antibiotic resistance in just five hours, which would serve as an important point-of-care diagnostic tool, especially in areas with limited resources.

Yang Gao et al, A simple, inexpensive, and rapid method to assess antibiotic effectiveness against exoelectrogenic bacteria, Biosensors and Bioelectronics (2020). DOI: 10.1016/j.bios.2020.112518

https://phys.org/news/2020-12-device-faster-antibiotic-resistant-ba...

AI predicts which drug combinations kill cancer cells

When healthcare professionals treat patients suffering from advanced cancers, they usually need to use a combination of therapies. In addition to cancer surgery, the patients are often treated with radiation therapy, medication or both.

Medication can be combined with drugs selected for specific cancer cells. Combinatorial drug therapies often improve the effectiveness of the treatment and can reduce the harmful side-effects if the dosage of individual drugs can be reduced. However, experimental screening of drug combinations is very slow and expensive, and therefore, often fails to discover the full benefits of combination therapy. With the help of a new machine-learning method, it is possible to identify the best combinations that selectively kill cancer cells with specific genetic or functional makeup.

developed a machine learning model that accurately predicts how combinations of cancer drugs kill various types of cancer cells. The new AI model was trained with a large set of data obtained from previous studies that investigated the association between drugs and cancer cells. "The model learned by the machine is actually a polynomial function familiar from school mathematics, but a very complex one. The model gives very accurate results. 

Heli Julkunen et al. Leveraging multi-way interactions for systematic prediction of pre-clinical drug combination effects, Nature Communications (2020). DOI: 10.1038/s41467-020-19950-z

https://medicalxpress.com/news/2020-12-ai-drug-combinations-cancer-...

Discovery shines light on how cancer cells could protect themselves

Researchers have found cancer cells can repair their DNA by using 'cables' in their nucleus. The findings open new possibilities for designing future cancer treatments. They  have made an unexpected discovery about cancer cells and how they harness 'cables' in a cell's nucleus to aid DNA repair and replication.

This discovery  revealed an unexpected function for the protein actin. Actin is well known as the protein that interacts with another protein called myosin to make muscles contract. Actin also forms cables inside cells that connect up and function like girders in a building, contributing to the structure and shape of cells.

While scientists have known for decades that actin plays this critical role in the main body of the cell, its role in the cell's control center, the nucleus, has been controversial.

For cancers to grow, cancer cells need to make many new copies of themselves. Every time this happens, the DNA in the cancer cells' nuclei must be replicated.

DNA replication in a cancer cell is like an old car traveling at its top speed—it frequently breaks down and has to get restarted. Cancer chemotherapy exploits this weakness in cancer cells by making the process break down even more frequently in an attempt to destroy them.

Researchers found that when cancer cells encounter problems replicating their DNA, actin cables form inside the nucleus. This allows the nucleus to change shape and increases the ability of the cancer cell to repair its DNA and restart the replication process.

Using advanced super resolution microscopy, the researchers showed that damaged DNA slides along the actin network to move to areas in the nucleus where repair occurs most efficiently. Scientists were previously unaware that cancer cells protected themselves in this way. Critically, this research found that actin performed these unexpected functions in response to treatment with chemotherapy and helped cancer cells resist the treatment.

Noa Lamm et al. Nuclear F-actin counteracts nuclear deformation and promotes fork repair during replication stress, Nature Cell Biology (2020). DOI: 10.1038/s41556-020-00605-6

https://medicalxpress.com/news/2020-12-discovery-cancer-cells.html?...

Breaking the rules of chemistry unlocks new reaction

Scientists have broken the rules of enzyme engineering to unlock a new method for creating chemical reactions that could unlock a wide range of new applications—from creating new drugs to food production. They show a new method to produce chemical molecules more efficiently through a new one step reaction in the enzyme.

They have demonstrated how a very simple mutation in one of the key residues of a useful enzyme has dramatically expanded its synthetic scope, enabling the use of the mutant variant in the preparation of challenging chemical molecules, as well as natural metabolites that are vital in many biological processes in the body."

Any textbook on enzymes will report on how the catalytic amino acids in any given enzyme family are highly conserved, they are in fact a signature of the type of chemistry an enzyme can do. Variations do occur and in some cases, if the replacing amino acid is similar, both can be found in significant proportion in Nature, but others can be much less common and are found only in a limited number of species.

"In this study theyhave explored an untouched area of enzyme engineering and modified the a key catalytic residue in the active site of an enzyme. Previously it was thought that doing this would cause a loss of activity of the enzyme but we have found this is not the case when this biocatalyst is used in a synthetic direction and in fact challenging but very useful molecules can now be made under mild conditions which could be easily scaled up and replicated commercially for use in a wide range of products.

Martina L. Contente et al, A strategic Ser/Cys exchange in the catalytic triad unlocks an acyltransferase-mediated synthesis of thioesters and tertiary amides, Nature Catalysis (2020). DOI: 10.1038/s41929-020-00539-0

https://phys.org/news/2020-12-chemistry-reaction.html?utm_source=nw...

Continents prone to destruction in their infancy, study finds

Geologists have shed new light on the early history of the Earth through their discovery that continents were weak and prone to destruction in their infancy.

The Earth is our home and over its 4,500,000,000 (4.5 billion) year history has evolved to form the environment we live in and the resources on which we depend.

However, the early history of Earth, covering its first 1.5 billion years remains almost unknown and, consequently, poorly understood.

This was the time of formation of the first continents, the emergence of land, the development of the early atmosphere, and the appearance of primordial life—all of which are the result of the dynamics of our planet's interiors.

Reproducing the conditions of the early Earth in computer-generated numerical models, scientists showed that the release of internal primordial heat, three to four times that of the present-day, caused large melting in the shallow mantle, which was then extruded as magma (molten rock) onto the Earth's surface.

According to the researchers, the shallow mantle left behind by this process was dehydrated and rigid and formed the keels of the first continents.

These results explain that continents remained weak and prone to destruction in their infancy, ~4.5 to ~4.0 billion years ago, and then progressively differentiated and became rigid over the next billion years to form the core of our modern continents. The emergence of these rigid early continents resulted in their weathering and erosion, changing the composition of the atmosphere and providing nutrients to the ocean seeding the development of life.

Thermochemical lithosphere differentiation and the origin of cratonic mantle, Nature (2020). DOI: 10.1038/s41586-020-2976-3 , www.nature.com/articles/s41586-020-2976-3

https://phys.org/news/2020-12-continents-prone-destruction-infancy....

Flightless birds more common globally before human-driven extinctions

There would be at least four times as many flightless bird species on Earth today if it were not for human influences, finds a study by researchers. The study, published in Science Advances, finds that flightlessness evolved much more frequently among birds than would be expected if you only looked at current species. 

Researchers say their findings show how human-driven extinctions have biased our understanding of evolution. 

Human impacts have substantially altered most ecosystems worldwide, and caused the extinction of hundreds of animal species. This can distort evolutionary patterns, especially if the characteristics being studied, such as flightlessness in birds, make species more vulnerable to extinction. We get a biased picture of how evolution really happens.

For the study, the researchers compiled an exhaustive list of all bird species known to have gone extinct since the rise of humans. They identified 581 bird species that went extinct from the Late Pleistocene (126,000 years ago) to the present, almost all of which were likely due to human influences.

The fossils or other records show that 166 of these extinct species lacked the ability to fly. Only 60 flightless bird species survive today.

Birds that cannot fly were much more diverse than previous studies had assumed, the study shows. The findings also confirm that flightless species were also much more likely to go extinct than species that could fly.

"Anthropogenic extinctions conceal widespread evolution of flightlessness in birds" Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abb6095

https://phys.org/news/2020-12-flightless-birds-common-globally-huma...

Cancer cells 'remove blindfold' to spread

Cunning ways of cancer cells

Cancer cells spread by switching on and off abilities to sense their surroundings, move, hide and grow new tumours, a new study has found.

This sensitivity to their surroundings is the key ability that makes small numbers of cancer cells better at spreading than other cells in a tumour, scientists  discovered.

The researchers developed a new method combining evolutionary biology and artificial intelligence techniques to study the movement and shape of cancer cells in more detail than ever, to learn why some can move more easily to different parts of the body and grow new tumours.

They found some cells displayed an apparent 'awareness' and ability to react to their surroundings, that was previously thought to be lost in of cancer. This means they may be able to adapt their shape to navigate barriers like blood vessel walls or other competing cells far more efficiently in order to replicate elsewhere.

 A phenotypic switch in the dispersal strategy of breast cancer cells selected for metastatic colonisation, Proceedings of the Royal Society B (2020). rspb.royalsocietypublishing.or … .1098/rspb.2020.2523

https://phys.org/news/2020-12-cancer-cells-blindfold.html?utm_sourc...

How microorganisms can produce renewable energy for us

Scientists have been studying the ability of microorganisms - the smallest living things on Earth—to produce energy other than for their natural activities for more than a century. This transformation is what scientists call a bioelectrochemical system.

Microbial fuel cell (MFC) is one form of bioelectrochemical system.

This system generally has one anode chamber (negative electrode) and one cathode chamber (positive electrode). MFC works in a similar way to batteries.

Microorganisms decompose organic or inorganic matters (or substrates) in the anode chamber to produce electrons. These electrons flow from anode to cathode via an external circuit made of conductive materials, such as copper-based wires, to generate electricity.

Deciding on the types of microorganism to generate the energy is an influential factor.

To date, the groups of microorganisms that demonstrate the ability to transfer electrons from their cells to the electrodes—called exoelectrogens – are in particular Geobacter and Shewnella.

Geobacter sulfurreducens KN400 can generate up to 3.9 Watts of electricity per square meter (W/m²) of anode area. Shewanella putrefaciens produces up to 4.4 W/m².

For its spaceship, NASA generates energy from Shewanella oneidensis bacteria.

Other microorganisms such as Rhodopseudomonas palustris DX1, Candida melibiosica, Saccharomyces ... also demonstrate exoelectrogenic capabilities.

A new exoelectrogenic microorganism is Desulfuromonas acetexigens.

Exoelectrogens can be obtained from various environments, such as waste water, compost, manure, dirt, river or lake sediments, swamps and marine ecosystems.

https://theconversation.com/this-is-how-microorganisms-can-produce-...

Plant-generated electricity

**

Protein molecules in cells function as miniature antennas

Researchers led by Josef Lazar of the Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) have demonstrated that molecules of fluorescent proteins act as antennas with optical properties (i.e. the ability to absorb and emit light) dependent on their spatial orientation. First discovered in jellyfish, fluorescent proteins are nowadays widely used in studies of molecular processes in living cells and organisms. The newly described properties of these molecules will find applications in basic biological research as well as in novel drug discovery. A team of researchers from IOCB Prague, the Institute of Microbiology, and the Institute of Molecular Genetics of the Czech Academy of Sciences has published the findings in the journal Proceedings of the National Academy of Sciences.

--

Carbon dioxide converted to ethylene—the 'rice of the industry'

In recent times, electrochemical conversion (e-chemical) technology—which converts carbon dioxide to high-value-added compounds using renewable electricity—has gained research attention as a carbon capture utilization (CCU) technology. This green carbon resource technology employs electrochemical reactions using carbon dioxide and water as the only feedstock chemical to synthesize various compounds, instead of conventional fossil fuels. Electrochemical CO2 conversion can produce value-added and important molecules in the petrochemical industry such as carbon monoxide and ethylene. Ethylene, referred to as the 'rice of the industry,' is widely used to produce various chemical products and polymers, but it is more challenging to produce from electrochemical CO2 reduction. The lack of understanding of the reaction pathway by which carbon dioxide is converted to ethylene has limited development of high-performance catalyst systems and in advancing its application to produce more valuable chemicals.

Reversal of biological clock restores vision in old mice

anti-ageing treatment restores sight in mice

Scientists recently have restored sight in mice using a "milestone" treatment that returns cells to a more youthful state and could one day help treat glaucoma and other age-related diseases.

The process offers the tantalising possibility of effectively turning back time at the cellular level, helping cells recover the ability to heal damage caused by injury, disease and age.

The treatment is based on the properties that cells have when the body is developing as an embryo. At that time, cells can repair and regenerate themselves, but that capacity declines rapidly with age.

The scientists reasoned that if cells could be induced to return to that youthful state, they would be able to repair damage.

To turn back the clock, they modified a process usually used to create the "blank slate" cells known as induced pluripotent stem cells.

Those cells are created by injecting a cocktail of four proteins that help reprogramme a cell.

The team did not want to reprogramme cells all the way back to that blank-slate status, but to restore them to a more youthful condition.

So they tweaked the cocktail, using just three of the "youth-restoring" proteins -- dubbed OSK -- in the hope they could turn the clock back to just the right point.

They targeted the retinal ganglion cells in the eye, which are linked to the brain through connections called axons.

These axons form the optic nerve -- and damage to them caused by injury, ageing or disease causes poor vision and blindness.

To test the effects of the cocktail, they first injected OSK into the eyes of mice with optic nerve injuries.

They saw a twofold increase in the number of surviving retinal ganglion cells and a fivefold increase in nerve regrowth.

The treatment allowed the nerves to grow back towards the brain. Normally they would simply die.

https://www.nature.com/articles/d41586-020-03403-0#:~:text=Research....

https://researchnews.cc/news/3916/-Milestone--anti-ageing-treatment...

Engineering a viral solution to cancer

Virotherapy is a treatment using biotechnology to convert viruses into therapeutic agents by reprogramming viruses to treat diseases. There are three main branches of virotherapy: anti-cancer oncolytic viruses,

While doctors can successfully treat some types of skin cancer at the surface with human-engineered viruses, scientists have yet to find a way to inject these types of viruses to seek and destroy other cancers in the body, such as lung cancer.

But medical researchers at Case Western Reserve University and Emory University are reporting remarkable success in eliminating human cancer cells in mouse models by injecting a modified strain of adenovirus into the bloodstream.

Oncolytic viruses, some found in nature and others modified in the laboratory, are a class of viruses that can infect and kill tumor cells, reproducing efficiently in the tumor without harming healthy cells.

These Scientists performed cryo-electron microscopy and structural modeling to visualize the engineered adenovirus generated by other scientists. Each change in the engineered virus allowed it to evade a particular defense by the body.

 tweaked the adenovirus (named the Ad5-3M virus, indicating three different engineered mutations) to successfully skirt three antiviral immune responses.

Those three responses were:

• Binding: Factors in the blood itself bind the virus and try to clear it through the liver.

• Cytokine storm: Flexible loops on the structure of the virus interact with the body’s host cells, triggering a massive and possibly deadly release of a group of proteins or peptides called cytokines.

• Pathogen clearance: Multiple components of the immune system act in a concerted way to clear pathogens from the body.

https://thedaily.case.edu/engineering-a-viral-solution-to-cancer/

https://researchnews.cc/news/3902/Engineering-a-viral-solution-to-c...

Peer Review: Implementing a "publish, then review" model of publishing

From July 2021 eLife will only review manuscripts already published as preprints, and will focus its editorial process on producing public reviews to be posted alongside the preprints.

https://elifesciences.org/articles/64910?utm_source=content_alert&a...

Organic Molecules

Physicists capture the sound of a 'perfect' fluid

For physicists, a perfect flow is more specific, referring to a fluid that flows with the smallest amount of friction, or viscosity, allowed by the laws of quantum mechanics. Such perfectly fluid behaviour is rare in nature, but it is thought to occur in the cores of neutron stars and in the soupy plasma of the early universe.

Now physicists have created a perfect fluid in the laboratory, and listened to how sound waves travel through it. The recording is a product of a glissando of sound waves that the team sent through a carefully controlled gas of elementary particles known as fermions. The pitches that can be heard are the particular frequencies at which the gas resonates like a plucked string.

The researchers analyzed thousands of sound waves traveling through this gas, to measure its "sound diffusion," or how quickly sound dissipates in the gas, which is related directly to a material's viscosity, or internal friction.

Surprisingly, they found that the fluid's sound diffusion was so low as to be described by a "quantum" amount of friction, given by a constant of nature known as Planck's constant, and the mass of the individual fermions in the fluid.

This fundamental value confirmed that the strongly interacting fermion gas behaves as a perfect fluid, and is universal in nature. The results, published today in the journal Science, demonstrate the first time that scientists have been able to measure sound diffusion in a perfect fluid.

Scientists can now use the fluid as a model of other, more complicated perfect flows, to estimate the viscosity of the plasma in the early universe, as well as the quantum friction within neutron stars—properties that would otherwise be impossible to calculate. Scientists might even be able to approximately predict the sounds they make.

"Universal sound diffusion in a strongly interacting Fermi gas" Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aaz5756

https://phys.org/news/2020-12-physicists-capture-fluid.html?utm_sou...

**How plants compete for underground real estate affects climate change and food production

You might have observed plants competing for sunlight—the way they stretch upwards and outwards to block each other's access to the sun's rays—but out of sight, another type of competition is happening underground. In the same way that you might change the way you forage for free snacks in the break room when your colleagues are present, plants change their use of underground resources when they're planted alongside other plants.

In a paper published today in Science, an international team of researchers  sheds light on the underground life of plants. Their research used a combination of modeling and a greenhouse experiment to discover whether plants invest differently in root structures when planted alone versus when planted alongside a neighbour.

Plants make two different types of roots: fine roots that absorb water and nutrients from the soil, and coarse transportation roots that transport these substances back to the plant's center. Plant "investment" in roots involves both the total volume of roots produced and the way in which these roots are distributed throughout the soil. A plant could concentrate all of its roots directly beneath its shoots, or it could spread its roots out horizontally to forage in the adjacent soil—which risks competition with the roots of neighboring plants.

The team's model predicted two potential outcomes for root investment when plants find themselves sharing soil. In the first outcome, the neighboring plants "cooperate" by segregating their root systems to reduce overlap, which leads to producing less roots overall than they would if they were solitary. In the second outcome, when a plant senses reduced resources on one side due to the presence of a neighbor, it shortens its root system on that side but invests more in roots directly below its stem.

Natural selection predicts this second scenario, because each plant acts to increase its own fitness, regardless of how those actions impact other individuals. If plants are very close together, this increased investment in root volume, despite segregation of those roots, could result in a tragedy of the commons, whereby the resources (in this case, soil moisture and nutrients) are depleted.

When this was tested on pepper plants, the team discovered that the outcome depends on how close a pair of plants are to each other. If planted very close together, plants will be more likely to heavily invest in their root systems to try to outcompete each other for finite underground resources; if they are planted further apart, they will likely invest less in their root systems than a solitary plant would.

Specifically, they found that when planted near others, pepper plants increased investment in roots locally and reduced how far they stretched their roots horizontally, to reduce overlap with neighbors. There was no evidence for a "tragedy of the commons" scenario, since there was no difference in the total root biomass or relative investment in roots compared to aboveground structures (including the number of seeds produced per plant) for solitary versus co-habiting plants.

 C. Cabal el al., "The exploitative segregation of plant roots," Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aba9877

https://phys.org/news/2020-12-underground-real-estate-affects-clima...

Scientists predict 'optimal' organism stress levels

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

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

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

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

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

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

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

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

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

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

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

Medicine-carriers made from human cells can cure lung infections

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

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

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

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

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

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

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

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

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

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

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

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

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

--

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

applications

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

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

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

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

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

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

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

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

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

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

Voyager spacecraft detect new type of solar electron burst

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

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

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

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

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

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

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

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

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

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

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

Anti-gravity: How a boat can float upside down

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

Boats floating at the interfaces of the levitating liquid layer.

Inverted pendulum with a vertically oscillated pivot.

Creation of a levitating liquid layers

Vision-restoring brain implants spell breakthrough

Scientists are a step closer to restoring vision for the blind, after building an implant that bypasses the eyes and allows monkeys to perceive artificially induced patterns in their brains. The technology, developed by a team at the Netherlands Institute for Neuroscience (NIN), was described in the journal Science on Thursday. It builds on an idea first conceived decades ago: electrically stimulating the brain so it "sees" lighted dots known as phosphenes, which can also be thought of as artificial pixels. But the concept had never realized its full potential because of technical limitations. A team led by NIN director Pieter Roelfsema developed implants consisting of 1024 electrodes wired into the visual cortex of two sighted monkeys, resulting in a much higher resolution than has previously been achieved. The visual cortex is located at the back of the brain and many of its features are common to humans and other primates. 

The NIN team profited from advances in miniaturization, and also devised a system to make sure their input currents were big enough to create noticeable dots, but not so great that the pixels grew too large.

They achieved this by placing some electrodes at a more advanced stage of the visual cortex, to monitor how much signal was coming through and then adjust the input.

https://science.sciencemag.org/content/370/6521/1168

https://researchnews.cc/news/3931/Vision-restoring-brain-implants-s...

Graphic on how scientists are developing techniques they hope will one day help restore sight to people with damaged eyes, by sending electronic signals directly to the brain. AFP.

Self-repairing gelatin-based film could be a smart move for electro...

Dropping a cell phone can sometimes cause superficial cracks to appear. But other times, the device can stop working altogether because fractures develop in the material that stores data. Now, researchers reporting in ACS Applied Polymer Materials have made an environmentally friendly, gelatin-based film that can repair itself multiple times and still maintain the electronic signals needed to access a devices data. The material could be used someday in smart electronics and health-monitoring devices.

https://www.acs.org/content/acs/en/pressroom/presspacs/2020/acs-pre...

Scientists Confirm Certain Spider Bites Inject Something Even Worse Than Venom: dreadful bacteria

A tiny brown invasive species of spider that's creeping its way across the UK has a dangerous reputation for dissolving flesh.

There's now compelling evidence suggesting that stories of the false widow spider (Steatoda nobilis) causing horrid skin infections has at least some basis in fact.

In most cases, the worst you might expect from a false widow spider bite is a few hours of pain around the injection site, and maybe a day or two of stiff joints. No worse than a wasp sting, really.

It's not the venom we need to be concerned about though – it's the risk posed by bacteria found on its fangs.

Every now and then a story will hit UK headlines of an arachnid bite leaving victims with something far worse than a throbbing finger. Swollen hands, rotting holes of pus, threats of amputation, or even deaths have provided ample nightmare fuel.

Though formal identification isn't always possible, the false widow typically cops the blame regardless.

Experts have understandably come to the spider's defence, arguing that even if it is guilty of leaving a couple of holes, it's the victim who supplies the necrotising bacteria by scratching at the site with dirty fingernails.

Hard evidence in support of either explanation has been scarce. So Dunbar's team collected specimens of false widows along with some lace-webbed (Amaurobius similis) and giant house spiders (Eratigena atrica) from gardens and pathways, and took them back to the lab.

There the arachnids had their bodies and chelicerae (appendages by their mouth parts) swabbed for bacteria, and venom collected from the false widows.

The study demonstrates that spiders are not just venomous but are also carriers of dangerous bacteria capable of producing severe infections. The biggest threat is that some of these bacteria are multi-drug resistant, making them particularly difficult to treat with regular medicine

https://www.nature.com/articles/s41598-020-77839-9

https://www.sciencealert.com/scientists-confirm-spider-s-bite-injec...

**

3 kinds of bias that shape your perception of science

China turns on nuclear-powered 'artificial sun' (Update)

China successfully powered up its "artificial sun" nuclear fusion reactor for the first time, state media reported Friday, marking a great advance in the country's nuclear power research capabilities.

The HL-2M Tokamak reactor is China's largest and most advanced nuclear fusion experimental research device, and scientists hope that the device can potentially unlock a powerful clean energy source.

It uses a powerful magnetic field to fuse hot plasma and can reach temperatures of over 150 million degrees Celsius, according to the People's Daily—approximately ten times hotter than the core of the sun.

Located in southwestern Sichuan province and completed late last year, the reactor is often called an "artificial sun" on account of the enormous heat and power it produces.

https://phys.org/news/2020-12-china-nuclear-powered-artificial-sun....

Research reveals how airflow inside a car may affect COVID-19 transmission risk

A new study of airflow patterns inside a car's passenger cabin offers some suggestions for potentially reducing the risk of COVID-19 transmission while sharing rides with others.

The study used computer models to simulate the airflow inside a compact car with various combinations of windows open or closed. The simulations showed that opening windows—the more windows the better—created airflow patterns that dramatically reduced the concentration of airborne particles exchanged between a driver and a single passenger. Blasting the car's ventilation system didn't circulate air nearly as well as a few open windows, the researchers found.

Driving around with the windows up and the air conditioning or heat on is definitely the worst scenario, according to the computer simulations by this team.

The best scenario they found was having all four windows open, but even having one or two open was far better than having them all closed.

The researchers stress that there's no way to eliminate risk completely—and, of course, current guidance from the U.S. Centers for Disease Control (CDC) notes that postponing travel and staying home is the best way to protect personal and community health. The goal of the study was simply to study how changes in airflow inside a car may worsen or reduce risk of pathogen transmission.

Varghese Mathai et al, Airflows inside passenger cars and implications for airborne disease transmission, Science Advances (2020). DOI: 10.1126/sciadv.abe0166

https://phys.org/news/2020-12-car-pandemic-windows.html?utm_source=...

Reviving puppetry for science, technology communication

https://www.freepressjournal.in/bhopal/madhya-pradesh-reviving-pupp...

The first observation of three massive gauge bosons produced in proton-proton collisions

The Standard Model, the most exhaustive existing theory outlining fundamental particle interactions, predicts the existence of what are known as triboson interactions. These interactions are processes in which three-gauge bosons are simultaneously produced from one Large Hadron Collider event.

Triboson interactions are incredibly rare, often up to hundreds of times rarer than Higgs boson events, as they typically take place once every 100 billion proton-proton collisions. Although the Standard Model predicts their existence, physicists had so far been unable to observe them experimentally.

The CMS Collaboration, a large group of researchers from numerous physics institutes worldwide have recently observed the production of three massive gauge bosons in proton-proton collisions for the first time ever. Their paper, published in Physical Review Letters, offers the first experimental evidence of the existence of triboson interactions, opening up new possibilities for the study the interactions between fundamental massive gauge bosons, namely the W±, Z, and Higgs boson.

Observation of the production of three massive gauge bosons at √s=13  TeV. Physical Review Letters(2020). DOI: 10.1103/PhysRevLett.125.151802.

https://phys.org/news/2020-12-triple-threat-massive-gauge-bosons.ht...

Scientists Discover an Unexpected Structure Hidden Inside Plant Cells

A team of researchers has just published a paper describing a surprising structure existing within an organelle – one that has remained hidden in plain sight for decades.

The organelle is called a peroxisome – a bubble-like single membrane filled with a granular protein matrix called a lumen. They aren't the most important cell machinery (not exactly a mitochondria or nucleus) but these very, very tiny cell organs have key roles in breaking down and synthesising molecules. Inside the peroxisomes of plant cells, researchers were surprised to find vesicles – something we didn't think the organelles had. Peroxisomes float around the cells of all multicellular organisms removing reactive molecules containing oxygen and helping break down fats. In humans and other mammals, they're only 0.1 micrometres – small enough that even with high power microscopes, there's not much to see. "Peroxisomes in yeast and mammalian cells are smaller than the resolution of light.

With fluorescence microscopy, you could only ever see a dot. That's just the limit that light can do.

https://www.nature.com/articles/s41467-020-20099-y

https://www.sciencealert.com/scientists-discover-surprise-structure...

**Elementary particles part ways with their properties

Yakir Aharonov and Daniel Rohrlich What is nonlocal in counterfactual quantum communication?, Physical Review Letters, Accepted Manuscript. journals.aps.org/prl/accepted/ … bc9200223328b0ab042b

Arxiv: arxiv.org/abs/2011.11667

--

**Research: Millions of smart devices vulnerable to hacking

https://techxplore.com/news/2020-12-millions-smart-devices-vulnerab...

Using targeted microbubbles to administer toxic cancer drugs

New research has shown how microbubbles carrying powerful cancer drugs can be guided to the site of a tumour using antibodies.

Microbubbles are small manufactured spheres half the size of a red blood cell—and scientists think they can be used to transport drugs to highly specific locations within the body.

Scientists have targeted microbubbles through the use of a 'navigational aid' - antibodies attracted to the growth hormone found in high levels in the blood vessels supplying a tumour.

The antibodies were attached to the microbubbles—and as a result of being attracted to the growth hormone, the microbubbles became concentrated at the site of the tumour. A pulse from an ultrasound device was used to burst open the microbubbles, and that released the anti-cancer agent.

One of the big problems with cancer drugs is that they are highly toxic to the rest of the body too. Microbubble technology allows us to use these very powerful drugs with precision and that reduces the risk of the drug damaging healthy cells nearby.

This work is about finely focused drug delivery. The animal-based study also revealed that by attaching the drug directly to the microbubbles allowed it to circulate in the body for longer, increasing delivery into the tumour—in effect making the drug more potent. As a result, the scientists were able to slow cancer growth with a much smaller drug dose.

Nicola Ingram et al, Ultrasound-triggered therapeutic microbubbles enhance the efficacy of cytotoxic drugs by increasing circulation and tumor drug accumulation and limiting bioavailability and toxicity in normal .tissues, Theranostics (2020). DOI: 10.7150/thno.49670

https://phys.org/news/2020-12-microbubbles-toxic-cancer-drugs.html?...

It's Not Just Humans. Sparrows Have Been Seen Using Preventative Medicine

 we might not be the only species that knows certain things in nature can help treat our ills.

A new correspondence paper has put forward the idea that russet sparrows (Passer cinnamomeus) in China are using wormwood (Artemisia verlotorum) leaves in their nest as a preventative medicine, to reduce parasites and help their babies get bigger.

The conclusion that animals can use medicinal plants to their benefit is not necessarily new
 Pregnant elephants in Kenya eat a particular leaf to induce birth, while many other mammals use medicinal plants to self-medicate – sometimes to prevent disease or just generally feel better from an ailment.

But it's still pretty amazing that a tiny sparrow might know that some plants are more important than others for protecting against disease.

"In China, russet sparrows incorporate wormwood leaves into their nests around the same time that local people hang wormwood from their doors as a traditional custom during the Dragon Boat Festival

The belief that this behaviour confers protection against ill health is supported by the description of anti-parasite compounds in wormwood. It has been suggested that the incorporation of fresh wormwood leaves into nests may serve a similar function for sparrows. the birds actively seek out nest locations close to the available wormwood and resupply established nests with fresh wormwood leaves gathered based solely on the leaves smell.

The nests containing wormwood leaves had lower parasite loads. By decreasing the number of parasites such as mites, the sparrows that add more wormwood leaves to their nest produce heavier and healthier chicks.

Sparrows use a medicinal herb to defend against parasites and increase offspring condition

https://www.cell.com/current-biology/fulltext/S0960-9822(20)31525-6

https://www.sciencealert.com/sparrows-have-been-seen-using-preventa...