Particles from paints, pesticides can have deadly impact

Hundreds of thousands of people around the world die too soon every year because of exposure to air pollution caused by our daily use of chemical products and fuels, including paints, pesticides, charcoal and gases from vehicle tailpipes, according to a new study.

Researchers calculated that air pollution caused by "anthropogenic secondary organic aerosol" causes 340,000-900,000 premature deaths. Those are tiny particles in the atmosphere that form from chemicals emitted by human activities.

The older idea was that to reduce premature mortality, you should target coal-fired power plants or the transportation sector. Yes, these are important, but this study is showing that if you're not getting at the cleaning and painting products and other everyday chemicals, then you're not getting at a major source.

Atmospheric researchers have long understood that particles in the atmosphere small enough to be inhaled can damage people's lungs and increase mortality. Studies have estimated that fine particle pollution, often called PM2.5, leads to 3-4 million premature deaths  globally per year, possibly more.

The new work suggests that a third broad category of chemicals—anthropogenic secondary organic pollutants—is a significant indirect source of deadly fine particles.

Benjamin A. Nault et al, Secondary organic aerosols from anthropogenic volatile organic compounds contribute substantially to air pollution mortality, Atmospheric Chemistry and Physics (2021). DOI: 10.5194/acp-21-11201-2021

https://phys.org/news/2021-08-particles-pesticides-deadly-impact.ht...

Cryptic transcription in mammalian stem cells linked to aging

Although visible signs of aging are usually unmistakable, unraveling what triggers them has been quite a challenge. Researchers have discovered that a cellular phenomenon called cryptic transcription, which had been previously described and linked to aging in yeasts and worms, is elevated in aging mammalian stem cells.

Researchers report in the journal Nature Aging that cryptic transcription occurs because a cellular mechanism that keeps it in check falls apart as cells get old. The findings suggest that strategies that control cryptic transcription could have pro-longevity effects.

In previous work, they showed that cryptic transcription in yeasts and worms is not only a marker of aging but also a cause. Reducing the amount of this aberrant transcription in these organisms prolonged their lifespan.

Cryptic transcription is a phenomenon that interferes with normal cellular processes. Normal gene transcription is a first step in the production of proteins. It begins in a specific location on the DNA called the promoter. This is where the protein coding gene begins to be transcribed into RNA, which is eventually translated into protein. Gene transcription is a well-regulated cellular process, but as cells age, they lose their ability to control it.

Promoters have a specific DNA sequence that identifies the starting point of the transcription process that is usually located preceding the actual protein coding sequence.

But promoter look-alike sequences do exist in other locations, including along the actual protein coding sequence, and they could start transcription and generate shorter transcripts, called cryptic transcripts.

worked with mammalian stem cells, which have shown to play a significant role in aging. They adapted a method to detect cryptic transcription to determine the level of this transcription in mice and human stem cells and cultured cells. When compared to young stem cells, older ones had increased cryptic transcription. They also looked into other aging cells and found that, in the majority of cells spanning a range of tissues, cryptic transcription was also elevated with age.

Altogether, these findings indicate that elevated cryptic transcription is a hallmark of mammalian aging. Young cells have mechanisms in place to prevent cryptic transcription. In aged mammalian cells, the researchers found that one such mechanisms, which involves limiting the access to chromatin, the material that makes up the chromosomes, is failing, facilitating the production of cryptic transcripts.

https://www.nature.com/articles/s43587-021-00091-x

https://researchnews.cc/news/8148/Cryptic-transcription-in-mammalia...

Driverless Tractor: India’s Innovation

Study reveals how smell receptors work

All senses must reckon with the richness of the world, but nothing matches the challenge faced by the olfactory system that underlies our sense of smell. We need only three receptors in our eyes to sense all the colors of the rainbow—that's because different hues emerge as light-waves that vary across just one dimension, their frequency. The vibrant colorful world, however, pales in comparison to the complexity of the chemical world, with its many millions of odors, each composed of hundreds of molecules, all varying greatly in shape, size and properties. The smell of coffee, for instance, emerges from a combination of more than 200 chemical components, each of which are structurally diverse, and none of which actually smells like coffee on its own.

To form a basic understanding of odorant recognition we need to know how a single receptor can recognize multiple different chemicals, which is a key feature of how the olfactory system works 

The olfactory system has to recognize a vast number of molecules with only a few hundred odour receptors or even less. It's clear that it had to evolve a different kind of logic than other sensory systems.

In a new study researchers offer answers to the decades-old question of odour recognition by providing the first-ever molecular views of an olfactory receptor at work.

The findings, published in Nature, reveal that olfactory receptors indeed follow a logic rarely seen in other receptors of the nervous system. While most receptors are precisely shaped to pair with only a few select molecules in a lock-and-key fashion, most olfactory receptors each bind to a large number of different molecules. Their promiscuity in pairing with a variety of odors allows each receptor to respond to many chemical components. From there, the brain can figure out the odor by considering the activation pattern of combinations of receptors.

 The structural basis of odorant recognition in insect olfactory receptors, Nature (2021). DOI: 10.1038/s41586-021-03794-8 , www.nature.com/articles/s41586-021-03794-8

https://phys.org/news/2021-08-reveals-receptors.html?utm_source=nwl...

Earth's energy budget is out of balance – here's how it's warming the climate

Energy can neither be created nor destroyed. That's a fundamental property of the universe.

Energy can be transformed, however. When the sun's rays reach Earth, they are transformed into random motions of molecules that you feel as heat. At the same time, Earth and the atmosphere are sending radiation back into space. The balance between the incoming and outgoing energy is known as Earth's "energy budget."

Our climate is determined by these energy flows. When the amount of energy coming in is more than the energy going out, the planet warms up.

That can happen in a few ways, such as when sea ice that normally reflects solar radiation back into space disappears and the dark ocean absorbs that energy instead. It also happens when greenhouse gases build up in the atmosphere and trap some of the energy that otherwise would have radiated away.

part 1

Virtually all the energy in the Earth's climate system comes from the sun. Only a tiny fraction is conducted upward from the Earth's interior.

On average, the planet receives 340.4 watts of sunshine per square meter. All sunshine falls on the daytime side, and the numbers are much higher at local noon.

Of that 340.4 watts per square meter:
99.9 watts are reflected back into space by clouds, dust, snow and the Earth's surface.
The remaining 240.5 watts are absorbed—about a quarter by the atmosphere and the rest by the surface of the planet. This radiation is transformed into thermal energy within the Earth system. Almost all of this absorbed energy is matched by energy emitted back into space. A tiny residual—0.6 watts per square meter—accumulates as global warming. That may not sound like much, but it adds up.
The atmosphere absorbs a lot of energy and emits it as radiation both into space and back down to the planet's surface. In fact, Earth's surface gets almost twice as much radiation from the atmosphere as it does from direct sunshine. That's primarily because the sun heats the surface only during the day, while the warm atmosphere is up there 24/7.

part 2

Earth's Delicate Energy Balance

Together, the energy reaching Earth's surface from the sun and from the atmosphere is about 504 watts per square meter. Earth's surface emits about 79% of that back out. The remaining surface energy goes into evaporating water and warming the air, oceans and land.

The tiny residual between incoming sunshine and outgoing infrared is due to the accumulation of greenhouse gases like carbon dioxide in the air. These gases are transparent to sunlight but opaque to infrared rays—they absorb and emit a lot of infrared rays back down.

Earth's surface temperature must increase in response until the balance between incoming and outgoing radiation is restored.

Doubling of carbon dioxide would add 3.7 watts of heat to every square meter of the Earth. Imagine old-fashioned incandescent night lights spaced every 3 feet over the entire world, left on forever.

At the current rate of emissions, greenhouse gas levels would double from preindustrial levels by the middle of the century.

Climate scientists calculate that adding this much heat to the world would warm Earth's climate by about 5 degrees Fahrenheit (3 C). Preventing this would require replacing fossil fuel combustion, the leading source of greenhouse gas emissions, with other forms of energy.

https://theconversation.com/earths-energy-budget-is-out-of-balance-...

part 4

Nearly 5 mn fewer girls to be born worldwide over next 10 years: study

An estimated 4.7 million fewer girls are expected to be born globally in the next 10 years because of sex-selective practices in countries with a cultural preference for male offspring, a trend that could undermine social cohesion in the long term, research showed on Tuesday. The research suggested that the projected shortfall in the number of girls being born will lead to a surplus of young men in around a third of the global population by 2030, which could lead to increased anti-social behaviour and violence. Sex-selective abortions have been on the rise for the past 40 years in countries throughout southeast Europe along with south and east Asia, with as-yet undetermined demographic impacts. To model what short- and long-term effect sex selection will have on societies, an international team of researchers analysed data from more than three billion births over the last 50 years. Focusing on 12 countries where the male-to-female ratio had increased since 1970 and another 17 where that ratio was at risk of increasing due to social or cultural trends, they simulated two scenarios.

The first assumed an increase in the rate of sex selection, based on statistical evidence.

The second scenario assumed increased sex selection in certain countries, based on observed trends and decreased fertility, but for which specific data were lacking.

In scenario 1, countries saw a shortfall of 4.7 million in the number of girls being born by 2030. For scenario 2, the figure jumped to more than 22 million globally by 2100.

Authors of the research, published in the BMJ medical journal, said the bias towards male offspring could lead to a "marriage squeeze" in affected countries.

"Fewer-than-expected females in a population could result in elevated levels of anti-social behaviour and violence, and may ultimately affect long-term stability and social sustainable development," they wrote.

The United Nations defines sex-selective practices alongside child marriage and female genital mutilation as harmful practices targeted under the Millennium Development Goals.

The authors of the new study called for better data collection of such practices in order to stamp them out, as well as wider education initiatives.

"A broader objective relates to the need to influence gender norms which lie at the core of harmful practices such as prenatal sex selection," they wrote.

"This calls for broader legal frameworks to ensure gender equality."

Source:  Agence France-Presse

New approach to information transfer reaches quantum speed limit

Researchers have  been investigating the theoretical constraints that will bound quantum technologies. One of the things researchers have discovered is that there are limits to how quickly quantum information can race across any quantum device.

These speed limits are called Lieb-Robinson bounds, and, for several years, some of the bounds have taunted researchers. For certain tasks, there was a gap between the best speeds allowed by theory and the speeds possible with the best algorithms anyone had designed. It's as though no car manufacturer could figure out how to make a model that reached the local highway limit.

But unlike speed limits on roadways, information speed limits can't be ignored when you're in a hurry—they are the inevitable results of the fundamental laws of physics. For any quantum task, there is a limit to how quickly interactions can make their influence felt (and thus transfer information) a certain distance away. The underlying rules define the best performance that is possible. In this way, information speed limits are more like the max score on an old school arcade game than traffic laws, and achieving the ultimate score is an alluring prize for scientists.

Now a team of researchers have found a quantum protocol that reaches the theoretical speed limits for certain quantum tasks. Their result provides new insight into designing optimal quantum algorithms and proves that there hasn't been a lower, undiscovered limit thwarting attempts to make better designs.

part1

Minh C. Tran et al, Optimal State Transfer and Entanglement Generation in Power-Law Interacting Systems, Physical Review X (2021). DOI: 10.1103/PhysRevX.11.031016

https://phys.org/news/2021-08-approach-quantum-limit.html?utm_sourc...

Unsurprisingly, the theoretical speed limit for sending information in a quantum device (such as a quantum computer) depends on the device's underlying structure. The new protocol is designed for quantum devices where the basic building blocks—qubits—influence each other even when they aren't right next to each other. In particular, the team designed the protocol for qubits that have interactions that weaken as the distance between them grows. The new protocol works for a range of interactions that don't weaken too rapidly, which covers the interactions in many practical building blocks of quantum technologies, including nitrogen-vacancy centers, Rydberg atoms, polar molecules and trapped ions.

Crucially, the protocol can transfer information contained in an unknown quantum state to a distant qubit, an essential feature for achieving many of the advantages promised by quantum computers. This limits the way information can be transferred and rules out some direct approaches, like just creating a copy of the information at the new location. (That requires knowing the quantum state you are transferring.)

In the new protocol, data stored on one qubit is shared with its neighbors, using a phenomenon called quantum entanglement. Then, since all those qubits help carry the information, they work together to spread it to other sets of qubits. Because more qubits are involved, they transfer the information even more quickly.

This process can be repeated to keep generating larger blocks of qubits that pass the information faster and faster. So instead of the straightforward method of qubits passing information one by one like a basketball team passing the ball down the court, the qubits are more like snowflakes that combine into a larger and more rapidly rolling snowball at each step. And the bigger the snowball, the more flakes stick with each revolution.

But that's maybe where the similarities to snowballs end. Unlike a real snowball, the quantum collection can also unroll itself. The information is left on the distant qubit when the process runs in reverse, returning all the other qubits to their original states.

When the researchers analyzed the process, they found that the snowballing qubits speed along the information at the theoretical limits allowed by physics. Since the protocol reaches the previously proven limit, no future protocol should be able to surpass it.

part2

Tips to tackle plastic pollution

Microwaving an ambulance. New technique could revolutionise how surfaces are disinfected
Microwave engineers, infectious disease specialists and polymer scientists have teamed up to create a novel microwave sterilization method that could revolutionize the way ambulances and hospitals are being disinfected.
At present, sterilization is done manually with conventional techniques that use chemicals. This can take around 30 to 40 minutes to disinfect a single ambulance.

During this time, the ambulance is out of action which puts increasing pressure on emergency services during busy times. The possibility of the new technique could drastically reduce the time it takes to get an ambulance safely back on the road to save lives.

In recent years, several other techniques have been proposed for disinfecting and sterilizing surfaces, ranging from hydrogen peroxide aerosols to UV irradiation and infrared radiation. However, these techniques have been shown to degrade surfaces over time, or to be harmful to humans if they are in close proximity. This has, so far, limited their long-term application.

In contrast, the new method works using electromagnetic waves, antennas, sensor beacons, and a liquid layer to rapidly heat-up and sterilize surfaces. Its automation means a person can easily operate the system from a safe distance rather than touching contaminated surfaces directly during cleaning.
The study used microwave beams emanating from antennas like those found in mobile smart phones and domestic Wi-Fi systems. The antennas allow the microwave radiation to be directed and focussed on locations where it is most needed.
K. Kossenas et al, A Methodology for Remote Microwave Sterilization Applicable to the Coronavirus and Other Pathogens using Retrodirective Antenna Arrays, IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology. DOI: 10.1109/JERM.2021.3077110
https://techxplore.com/news/2021-08-microwave-ambulance-technique-r...

When faces are partially covered, neither people nor algorithms are...

Artificial systems such as homecare robots or driver-assistance technology are becoming more common, and it's timely to investigate whether people or algorithms are better at reading emotions, particularly given the added challenge brought on by face coverings.

Using two CRISPR enzymes, a COVID diagnostic in only 20 minutes

Frequent, rapid testing for COVID-19 is critical to controlling the spread of outbreaks, especially as new, more transmissible variants emerge.

A research team is aiming to develop a diagnostic test that is much faster and easier to deploy than qRT-PCR. It has now combined two different types of CRISPR enzymes to create an assay that can detect small amounts of viral RNA in less than an hour.

While the new technique is not yet at the stage where it rivals the sensitivity of qRT-PCR, which can detect just a few copies of the virus per microliter of liquid, it is already able to pick up levels of viral RNA—about 30 copies per microliter—sufficient to be used to surveil the population and limit the spread of infections.

Liu, T.Y. et al. Accelerated RNA detection using tandem CRISPR nucleases. Nat Chem Biol (2021). DOI: 10.1038/s41589-021-00842-2

https://phys.org/news/2021-08-crispr-enzymes-covid-diagnostic-minut...

Antibody findings spark ideas for pan-coronavirus vaccine

Three epidemic or pandemic coronaviruses—SARS-CoV, MERS-CoV, & SARS-CoV-2—have spilled over from animals to cause deadly illness in humans in the past 20 years. Virus researchers are determined to discover a means to broadly safeguard people from the continuing threat of emerging coronaviruses.

Clues for creating such an overarching countermeasure might come from a rare type of human antibody that can neutralize several different coronaviruses. These antibodies have been detected in some people who have recovered from COVID-19.

A paper appearing Aug. 3 in the journal Science describes research on five such human monoclonal antibodies that can cross-react with a number of beta-coronaviruses. These antibodies target a structure, called stem helix, in the spike protein of these viruses. The spike protein is critical to the virus' ability to overtake host cells.

The stem helix in the spike protein has remained conserved during the evolution of certain coronaviruses. That means it is much less prone to genetic changes and is similar in various coronaviruses. These include those originating in bats that have become dangerous pathogens in people, and another subgenus that causes a serious human lung disease transmitted by dromedary camels, as well as a few other subgenera that cause simple common cold symptoms.

The researchers explain in their paper that they were interested in exploring antibodies that target highly conserved regions of the spike protein machinery that enable coronaviruses to fuse with the membrane of host cells. 

An antibody's ability to bind to the less mutable fusion machinery is what allows it to neutralize distantly related coronaviruses.

To find these sorts of antibodies, the researchers examined certain memory B cells from COVID-19 convalescent donors. Memory B cells are white blood cells that recognize and respond to pathogens that have tried to attack the body during a previous encounter.

part 1

Out of five promising antibodies that they isolated, the scientists decided to concentrate on one designated S2P6. Molecular structure analysis and functional studies showed that this human monoclonal antibody had impressive breadth: it was able to neutralize three different subgenera of beta-coronaviruses. The scientists observed that it did so by inhibiting the virus' ability to fuse with cell membranes.

The researchers went on to test if the S2P6 stem helix antibody could protect against SARS-CoV-2 by administering it to hamsters 24 hours before exposure. They found that this antibody reduced the viral load of SARS-CoV-2 by inhibiting entry of the virus and by enhancing additional anti-viral and virus-clearing cellular immune responses.

Studies of the plasma from pre-pandemic human samples, as well as from COVID-vaccinated and COVID-recovered individuals were also analyzed to see how frequently the stem-helix targeting antibodies appeared. They highest frequencies occurred in people who had recovered from COVID-19, then were later vaccinated. Overall, however, the data from this study shows that, while it does occur, it is relatively rare for SARS-CoV-2 to elicit plasma stem-helix antibody responses. The researchers hope that additional studies might reveal whether this is the case for antibodies that target other parts of the coronavirus fusion machinery or only for those that target the stem helix.

The researchers also looked at how the broadly reactive monoclonal antibodies studied in this project might have originated. Their findings suggest that they may have resulted from the priming of B memory cells through one of the common cold-inducing coronaviruses. Then the virus-specific B cells gained cross-reactivity through somatic mutations occurring during the body's immune response to a natural infection with another type of coronavirus.

The results from this study indicate that eliciting a sufficient quantity of stem helix antibodies through a standard vaccination development approach likely would be difficult. However, the researchers propose that recent computational protein-design advances for potential vaccine candidates against respiratory syncytial viruses and multiple influenza viruses might be adapted to try to induce broad beta coronavirus immunity and overcome the pan-coronavirus vaccine challenge.

Dora Pinto et al, Broad betacoronavirus neutralization by a stem helix–specific human antibody, Science (2021). DOI: 10.1126/science.abj3321

https://medicalxpress.com/news/2021-08-antibody-ideas-pan-coronavir...

Environmental impact of bottled water up to 3,500 times higher than tap water

The consumption of bottled water has been increasing sharply in recent years on a global scale. According to previous research, this trend can be partly explained by subjective factors like risk perception, taste, odor, lack of trust in public tap water quality and marketing by bottled water companies.

Environmental and health impacts are usually assessed separately due to the different methodologies applied and resulting outcomes. Environmental impacts can be estimated with a methodology called Life Cycle Assessment (LCA), while the consequences in human helath are estimated with an approach called Health Impact Assessment (HIA). This study has tried to overcome this methodological barrier for the first time by combining LCA and HIA in the same analysis.

The results of work done in Barcelona, Spain, showed that if the whole population of the city decided to shift to bottled water, the production required would take a toll of 1.43 species lost per year and cost of 83.9 million USD per year due to extraction of raw materials. This is approximately 1,400 times more impact in ecosystems and 3,500 times higher cost of resource extraction compared to the scenario where the whole population would shift to tap water.

The results results show that considering both the environmental and the health effects, tap water is a better option than bottled water, because bottled water generates a wider range of impacts.

Cristina M. Villanueva et al, Health and environmental impacts of drinking water choices in Barcelona, Spain: A modelling study, Science of The Total Environment (2021). DOI: 10.1016/j.scitotenv.2021.148884

https://phys.org/news/2021-08-environmental-impact-bottled-higher.h...

Microbes engineered to convert sugar into a chemical found in tires

The future environmental footprint of the tire industry could be substantially shrunk thanks to a new ecofriendly way found by researchers that harnesses bacteria to make a chemical used in synthetic rubber.

Each year, factories around the world churn out more than 12 million metric tons of the organic chemical 1,3-butadiene, which is used in tires, adhesives, sealants and other plastic and rubber products. They produce it by an energy-intensive process that relies on petroleum, which contributes to climate change.

Scientists have tried for many years to create 1,3-butadiene from more environmentally friendly starting materials by using specially designed microbes. But no one had previously succeeded in transforming a simple sugar such as glucose into the chemical in one easy step.

Now, by engineering bacteria to convert glucose into 1,3-butadiene,  researchers have devised a sustainable approach to rubber and plastic production. They constructed a novel artificial metabolic pathway and produced 1,3-butadiene directly from a renewable source—glucose. They first engineered a bacterial enzyme that could convert a biological compound that can be developed from glucose into 1,3-butadiene . The researchers then modified a strain of the bacterium Escherichia coli to use this enzyme and produce the chemical. Since 1,3-butadiene is a gas at room temperature, it can be easily captured as the bacteria continue to divide and grow.

Yutaro Mori et al, Direct 1,3-butadiene biosynthesis in Escherichia coli via a tailored ferulic acid decarboxylase mutant, Nature Communications (2021). DOI: 10.1038/s41467-021-22504-6

https://phys.org/news/2021-08-microbes-sugar-chemical.html?utm_sour...

Freeze-Dried Mouse Sperm Sent by Postcard Produces Baby Mice

Rather than relying on samples that need to be shipped in glass vials and on ice, researchers have developed a new method that allows mouse sperm to be sent easily at room temperature using standard mail delivery.

The new method, detailed in a study published today (August 5) in iScience, builds on the team’s previous work, which involved sending dehydrated mouse sperm stored in glass ampoules to the International Space Station to study how radiation affects mammalian cells. Drying the samples, the authors say, does away with the need for cold storage, and they’ve since refined the method further so that they can store sperm from thousands of different mouse strains in a single three-ring binder.

https://www.cell.com/iscience/fulltext/S2589-0042(21)00783-5?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004221007835%3Fshowall%3Dtrue

https://www.the-scientist.com/news-opinion/freeze-dried-mouse-sperm...

 Machu Picchu older than previously thought

Machu Picchu, the famous 15th-century Inca site in southern Peru, is up to several decades older than previously thought, according to a new study .

Until now, estimates of Machu Picchu's antiquity and the length of its occupation were based on contradictory historical accounts written by Spaniards in the period following the Spanish conquest.

Researchers used  used accelerator mass spectrometry (AMS)—an advanced form of radiocarbon dating—to date human remains recovered during the early 20th century at the monumental complex and onetime country estate of Inca Emperor Pachacuti located on the eastern face of the Andes Mountains.

Their findings, published in the journal Antiquity, reveal that Machu Picchu was in use from about A.D. 1420 to A.D. 1530—ending around the time of the Spanish conquest—making the site at least 20 years older than the accepted historical record suggests and raising questions about our understanding of Inca chronology.

Historical sources dating from the Spanish invasion of the Inca Empire indicate that Pachacuti seized power in A.D. 1438 and subsequently conquered the lower Urubamba Valley where Machu Picchu is located. Based on those records, scholars have estimated that the site was built after A.D. 1440, and perhaps as late as A.D. 1450, depending on how long it took Pachacuti to subdue the region and construct the stone palace.

The AMS technique can date bones and teeth that contain even small amounts of organic material, expanding the pool of remains suitable for scientific analysis. For this study, the researchers used it to analyze human samples from 26 individuals that were recovered from four cemeteries at Machu Picchu in 1912 during excavations. The bones and teeth used in the analysis likely belonged to retainers, or attendants, who were assigned to the royal estate, the study states. The remains show little evidence of involvement in heavy physical labor, such as construction, meaning that they likely were from the period when the site functioned as a country palace, not when it was being built, the researchers said.

The AMS testing indicates that the historical timeline is inaccurate. This is the first study based on scientific evidence to provide an estimate for the founding of Machu Picchu and the length of its occupation, giving us a clearer picture of the site's origins and history.

The finding suggests that Pachacuti, whose reign set the Inca on the path to becoming pre-Columbian America's largest and most powerful empire, gained power and began his conquests decades earlier than textual sources indicate.

The results suggest that the discussion of the development of the Inca empire based primarily on colonial records needs revision. Modern radiocarbon methods provide a better foundation than the historical records for understanding Inca chronology.

https://www.cambridge.org/core/journals/antiquity/article/new-ams-d...

https://researchnews.cc/news/8221/Study--Machu-Picchu-older-than-ex...

Organ transplant recipients significantly protected by COVID-19 vaccination

 In a Brief Communication, published July 29, 2021 in the journal Transplant Infectious Disease, a team of physician-scientists.

found that solid organ transplant recipients who were vaccinated experienced an almost 80 percent reduction in the incidence of symptomatic COVID-19 compared to unvaccinated counterparts during the same time. Persons who have received an organ transplant are considered to be at increased risk for COVID-19 and for a severe outcome because their immune systems are necessarily suppressed to ensure their transplants are successful and lasting.

These new findings offer strong evidence that getting vaccinated provides significant protection even to the immuno-suppressed people.

During the study period, there were 65 diagnosed cases of COVID-19 among the organ recipients: four among fully vaccinated individuals and 61 among the controls (two involving partially vaccinated individuals). There were no deaths among the breakthrough COVID-19 cases, but two among the 61 control cases.

it demonstrates real world clinical effectiveness of COVID-19 vaccination in a vulnerable population. Second, the effectiveness is better than expected, given that studies have found that only about half of solid organ transplant recipients develop detectable anti-spike antibodies after vaccination.

https://researchnews.cc/news/8207/Organ-transplant-recipients-signi...

**

Sunscreen Chemistry and Action

See how aerosol particles escape from musical instruments

Menopause breakthrough as scientists find genes to delay ageing process ( Game News )

Scientists Identify Extremely Tough Bacterial Species That Thrive Inside Concrete

Some types of bacteria are hardy enough to survive in the most inhospitable of conditions – and that includes concrete, as a new study proves. Not only can microbes survive in this dry, inhospitable building material, they can actually thrive there too.

Research shows that bacteria could provide early warnings of moisture-induced alkali-silica reactions (or 'concrete cancer') that can lead to structural deficiencies. Further down the line, we might even be able to harness bacteria to repair damage to bridges and roads.

While previous studies had already established that bacteria are able to make their homes inside concrete, here the scientists wanted to take a closer look at which microbes were present and how their communities might change over time.

After regular monitoring over two years on the roof of the lab, the most common bacteria discovered in the DNA analysis of the samples were Proteobacteria, Firmicutes, and Actinobacteria. Around 50-60 percent of the bacteria probably came from the raw materials, the researchers say, especially gravel.

The team observed that bacterial diversity dropped over time, though some types of bacteria had 'bounces' as the seasons changed – perhaps an indication that the availability of food sources was changing as well.

It's possible they're eating the dead bodies of other microbes. If there's nothing to eat, some of them can form spores or form a dormant cell type and do nothing until it rains, then eat as much as they can and go dormant again.

As some bacteria can produce calcium carbonate – which is suitable for filling in concrete cracks and pores – there's a hope that these microorganisms could be used to help repair buildings and infrastructure, though that sort of application is a long way off.

The researchers think  the microbes are not damaging the concrete.

https://journals.asm.org/doi/10.1128/mSystems.01153-20

https://www.sciencealert.com/some-bacteria-are-so-tough-they-can-gr...

Covid-19 patient develops rare white fungus abscess in brain after recovery

Lake Huron sinkhole surprise: The rise of oxygen on early Earth linked to changing planetary rotation rate

The rise of oxygen levels early in Earth's history paved the way for the spectacular diversity of animal life. But for decades, scientists have struggled to explain the factors that controlled this gradual and stepwise process, which unfolded over nearly 2 billion years.

Now an international research team is proposing that increasing day length on the early Earth—the spinning of the young planet gradually slowed over time, making the days longer—may have boosted the amount of oxygen released by photosynthetic cyanobacteria, thereby shaping the timing of Earth's oxygenation.

Their conclusion was inspired by a study of present-day microbial communities growing under extreme conditions at the bottom of a submerged Lake Huron sinkhole, 80 feet below the water's surface. The water in the Middle Island Sinkhole is rich in sulfur and low in oxygen, and the brightly colored bacteria that thrive there are considered good analogs for the single-celled organisms that formed mat-like colonies billions of years ago, carpeting both land and seafloor surfaces.

The researchers show that longer day length increases the amount of oxygen released by photosynthetic microbial mats. That finding, in turn, points to a previously unconsidered link between Earth's oxygenation history and its rotation rate. While the Earth now spins on its axis once every 24 hours, day length was possibly as brief as 6 hours during the planet's infancy.

Possible link between Earth's rotation rate and oxygenation, Nature Geoscience (2021). DOI: 10.1038/s41561-021-00784-3 , www.nature.com/articles/s41561-021-00784-3

https://phys.org/news/2021-08-lake-huron-sinkhole-oxygen-early.html...

 Scientists find the missing link in our body's blood pressure control

Researchers have determined the location of natural blood-pressure barometers inside our bodies that have eluded scientists for more than 60 years.

These cellular sensors detect subtle changes in blood pressure and adjust hormone levels to keep it in check. Scientists have long suspected that these barometers, or "baroreceptors," existed in specialized kidney cells called renin cells, but no one has been able to locate the baroreceptors until now.

The new findings finally reveal where the barometers are located, how they work and how they help prevent high blood pressure (hypertension) or low blood pressure (hypotension). The researchers hope the insights will lead to new treatments for high blood pressure.

the renin cells are sensors and responders.

Using a combination of innovative lab models, they determined that the baroreceptor was a "mechanotransducer" inside renin cells. This mechanotransducer detects pressure changes outside the cell, then transmits these mechanical signals to the cell nucleus, like how the cochlea in our ear turns sound vibrations into nerve impulses our brain can understand.

The researchers have unlocked exactly how the baroreceptors work. They found that applying pressure to renin cells in lab dishes triggered changes within the cells and decreased activity of the renin gene, Ren1. The scientists also compared differences in gene activity in kidneys exposed to lower pressure and those exposed to higher pressure.

Ultimately, when the baroreceptors detect too much pressure outside the renin cell, production of renin is restricted, while blood pressure that is too low prompts the production of more renin. This marvelous mechanism is vital to the body's ability to maintain the correct blood pressure. And now, after more than 60 years, we finally understand how and why.

Hirofumi Watanabe et al, Renin Cell Baroreceptor, a Nuclear Mechanotransducer Central for Homeostasis, Circulation Research (2021). DOI: 10.1161/CIRCRESAHA.120.318711

https://medicalxpress.com/news/2021-08-years-scientists-link-body-b...

Old vaccine for tuberculosis may help protect older people against COVID-19

A team of researchers from the CMR-National Institute for Research in Tuberculosis and the ICMR-National Institute of Epidemiology, both in India, has found evidence suggesting that an old vaccine used to reduce the threat of tuberculosis may give older people some protection against COVID-19. In their paper published in the journal Science Advances, the group describes their study of the Bacillus Calmette-Guérin (BCG) vaccine as a possible preventive measure for older people. Valerie Koeken with Radboud University Medical Center has published a Focus piece in the same journal issue explaining why inflammation is more of a concern with older people and outlining the work by the team in India.

As Koeken notes, as people grow older, they tend to develop low-grade, chronic inflammation, which makes them more susceptible to many types of diseases—it can also increase symptoms from diseases such as COVID-19, which explains in part why older people are much more likely to die from such infections. In this new effort, the researchers took a new look at an old vaccine to find out if it might prove useful for unvaccinated older people.

The study involved vaccinating 82 volunteers between the ages of 60 and 80 with the BCG vaccine and then studying blood samples taken a month later. In analyzing the samples, the researchers found decreases in several cytokines that have been associated with promoting inflammation: IL-6, type 1 interferons, interleukin-2 (IL-2) and TNF-alpha GM-CSF. The levels of the same cytokines were also found to be lower than those for a control group of unvaccinated volunteers. The researchers found that the BCG-vaccinated volunteers also had lower levels of some chemokines, such as matrix metalloproteinases and phase proteins, both of which have also been associated with promoting inflammation.

The researchers note that many of the cytokines that were reduced in the BCG volunteers have been identified as drivers of more severe COVID-19, which they also note suggests that the BCG vaccine might prove useful as a stop-gap measure for older people awaiting vaccination—if it could reduce inflammation in infected patients, it might save lives.

Nathella Pavan Kumar et al, Effect of BCG vaccination on proinflammatory responses in elderly individuals, Science Advances (2021). DOI: 10.1126/sciadv.abg7181

https://researchnews.cc/news/8238/Old-vaccine-for-tuberculosis-may-...

Researchers find possible culprit of inflammation that causes death...

As clinical evidence mounts that the leading cause of death in COVID-19 patients is the dangerous condition known as a cytokine storm, researchers have identified a protein in the blood that could be responsible. The team found that COVID-19 patients have significantly elevated levels of a protein called galectin-9 in their blood plasma. Perhaps more importantly, they also found a positive correlation between the levels of galectin-9 and pro-inflammatory cytokines released in the blood, which can lead to a cytokine storm. 

The findings suggest that galectin-9 levels in the body could be used as a biomarker to diagnose COVID-19 using a patient’s blood, potentially providing another non-invasive tool for COVID-19 testing. The levels could also be used to indicate the severity of the disease, though further study on that aspect is required.

The discovery of elevated galectin-9 levels in COVID-19 patients is important because of the positive correlation between the protein and a wide range of pro-inflammatory cytokines.

Cytokines as small cell-signalling proteins are involved in checks and balances in the immune system; they can turn on or turn off some cells to regulate the immune system. In the context of COVID, the problem is that there is a dysregulation of cytokine production—they are released very quickly in elevated levels. That’s what we call a ‘cytokine storm.

 galectin-9 is responsible for instructing immune cells to release the pro-inflammatory cytokines quickly in response to COVID-19 infection by binding to immune cells and forcing them to produce the cytokines. Further, as tissues are damaged as a result of inflammation, more galectin-9 is released from the cells—which activates more immune cells and releases more cytokines in a vicious cycle. The resulting cytokine storm damages tissue and organs, causes severe inflammation and can lead to death.

The next step is to develop treatments that block or inhibit the protein

https://journals.asm.org/doi/full/10.1128/mBio.00384-21

https://www.ualberta.ca/folio/2021/08/researchers-find-possible-cul...

Climate change: IPCC report is 'code red for humanity'

'It's not climate change, it's climate chaos', wars UN | UN Climate report 2021

Middle-age height loss linked to heightened death risk in northern European women

Height loss in middle age is linked to a heightened risk of early death, primarily from heart disease or stroke—at least in Northern European women—suggests research published in the online journal BMJ Open.

But regular physical activity may help to stave off mid-life shrinkage, as well as lowering cardiovascular disease risk, the findings indicate.

People tend to start losing height once they reach their 50s, a process that speeds up during their 70s. Height loss is usually caused by vertebral disc shrinkage, spinal compression fractures, and changes in posture.

While some degree of height loss is associated with natural aging, previous research suggests that it may also be associated with an increased risk of death from heart disease.

In the study, each cm of height loss was associated with 14% and 21% greater odds of death from any cause among the Swedish and Danish women, respectively, after adjusting for potentially influential factors.

Short stature and high leisure time physical activity (including participation in competitive sports) at study entry were associated with less height loss, independent of age.

Major height loss, defined as more than 2 cm, was associated with 74% and 80% greater odds of death, respectively, among two groups of women.

Other unmeasured factors may also have influenced the findings, they add. These include early life physical activity and exposure to tobacco (either through second-hand smoke or smoking themselves], peak bone mass, underlying health conditions and medical treatments.

Nevertheless, the findings prompt the researchers to conclude that mid-life height loss "is a risk marker for earlier mortality in northern European women."

Specifically, the risk of cardiovascular disease is increased in women who lose height, with death from stroke a major contributor to this association, they add.

 Loss of height predicts total and cardiovascular mortality: a cohort study of northern European women, BMJ Open (2021). DOI: 10.1136/bmjopen-2021-049122

https://medicalxpress.com/news/2021-08-middle-age-height-loss-linke...

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Organoid bladders reveal secrets of UTIs

Urinary tract infections (UTIs) are among the most common bacterial infections. They usually require treatment with antibiotics, and almost a quarter of treated cases lead to recurrent infection. The vast majority of UTIs are caused by a subspecies of the bacterium Escherichia coli, which infect cells that line the bladder wall and form what are known as “intracellular bacterial communities”.

The “communities” repeatedly rupture and bacteria re-enter neighboring cells, eventually killing off the so-called “umbrella cells” that line the outermost layer of the bladder’s epithelium. The loss of umbrella cells then allows the bacteria to invade the deeper layers of the bladder, where they can form “quiescent intracellular reservoirs” that are resistant to antibiotics and cause UTI recurrences. The dynamics of these events are hard to capture in vivo in animal models.

“Infection dynamics are difficult to capture from static imaging of tissue explants at serial time points,” says Kunal Sharma, the lead author on the two studies. “Thus far, in vitro models have not recapitulated bladder architecture with sufficient fidelity to study the time course of these events.”

Part 1

To address this, the group of Professor John McKinney at EPFL’s School of Life Sciences developed two complementary bladder models to study UTIs in a more controlled way. The first model consists of bladder organoids that recreate the 3D stratified architecture of the bladder epithelium. Organoids are tiny lab-grown tissues and organs that are anatomically correct and physiologically functional.

The second model is a bladder-on-a-chip that incorporates physiological stimuli, e.g. the mechanical effect of bladder filling and voiding, as well as an interface with the vasculature to study immune cell migration to sites of infection. The advances were published in the journals Cell Reports and eLife.

“By generating organoids from a mouse with a fluorescent label incorporated within cell membranes, we could use live-cell confocal imaging at EPFL’s BioImaging & Optics Core Facility to identify specific bacterial niches within the organoid with a high spatial resolution,” says Sharma. “By imaging multiple organoids, we managed to identify heterogeneity and diverse outcomes of host-pathogen interactions. This proof-of-concept system has shown promising potential for follow up studies on bacterial persistence to antibiotics and the dynamics of immune cell responses to infection.”

In combination with volumetric electron microscopy performed by EPFL’s Biological Electron Microscopy Facility, the researchers found that solitary bacteria rapidly invade into deeper layers of the bladder, independently of the formation of intracellular bacterial communities, where they are protected from antibiotics and host immune cells. These findings could be leveraged to improve UTI treatment strategies.

part 2

Innovative coating for blood vessels reduces rejection of transplanted organs
Researchers have found a way to reduce organ rejection following a transplant by using a special polymer to coat blood vessels on the organ to be transplanted.

The polymer, developed by UBC medicine professor Dr. Jayachandran Kizhakkedathu and his team at the Centre for Blood Research and Life Sciences Institute, substantially diminished rejection of transplants in mice when tested by collaborators at SFU and Northwestern University.
The findings were published in Nature Biomedical Engineering.

The discovery has the potential to eliminate the need for drugs—typically with serious side effects—on which transplant recipients rely to prevent their immune systems from attacking a new organ as a foreign object.

Blood vessels in our organs are protected with a coating of special types of sugars that suppress the immune system’s reaction, but in the process of procuring organs for transplantation, these sugars are damaged and no longer able to transmit their message.

Researchers now  synthesized a polymer to mimic these sugars and developed a chemical process for applying it to the blood vessels. This new technology  prevented rejection in the studies.

The procedure has been applied only to blood vessels and kidneys in mice so far. Clinical trials in humans could still be several years away. Still, the researchers are optimistic it could work equally well on lungs, hearts and other organs, which would be great news for prospective recipients of donated organs.

1. Erika M. J. Siren, Haiming D. Luo, Franklin Tam, Ashani Montgomery, Winnie Enns, Haisle Moon, Lyann Sim, Kevin Rey, Qiunong Guan, Jiao-Jing Wang, Christine M. Wardell, Mahdis Monajemi, Majid Mojibian, Megan K. Levings, Zheng J. Zhang, Caigan Du, Stephen G. Withers, Jonathan C. Choy, Jayachandran N. Kizhakkedathu. Prevention of vascular-allograft rejection by protecting the endothelial glycocalyx with immunosuppressive polymers. Nature Biomedical Engineering, 2021; DOI: 10.1038/s41551-021-00777-y

https://researchnews.cc/news/8271/Innovative-coating-for-blood-vess...

Chameleon robot: 

Hyeonseok Kim et al, Biomimetic chameleon soft robot with artificial crypsis and disruptive coloration skin, Nature Communications (2021). DOI: 10.1038/s41467-021-24916-w

https://techxplore.com/news/2021-08-soft-robot-chameleon-real-time-...

Lichens may one day detoxify the air in your home

When smoke from fires darken the skies as they did last summer, hunkering down indoors makes good sense. But on most days throughout the year, the air we breathe indoors carries far more pollutants than outdoor air. Exposure is highest in crowded homes where space is a luxury, leading the EPA to rank indoor air quality as one of the top five public health concerns.

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Skull birth defect detailed in cell-by-cell description

Contrary to the popular song, the neck bone is actually connected to one of 22 separate head bones that make up the human skull. These plate-like bones intersect at specialized joints called sutures, which normally allow the skull to expand as the brain grows, but are absent in children with a birth defect called craniosynostosis. A new study in Nature Communications presents a detailed cellular atlas of the developing coronal suture, the one most commonly fused as a consequence of single gene mutations. 

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Humans will always have oxygen to breathe, but we can't say the sam...

There is nothing more fundamental to humans than the availability of oxygen. We give little thought to the oxygen we need, we just breathe, but where does it come from?

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Study says 'blue hydrogen' likely bad for climate

Use of "clean" hydrogen has been seen as a viable and environmentally benign energy alternative, but a study released Thursday said it could lead to higher greenhouse gas emissions than coal.

Touted as clean, 'blue' hydrogen may be worse than gas, coal

"Blue" hydrogen—an energy source that involves a process for making hydrogen by using methane in natural gas—is being lauded as a clean, green energy to help reduce global warming. But Cornell and Stanford University researchers believe it may harm the climate more than burning fossil fuel.

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Is your mobile provider tracking your location? This new technology...

Right now, there is a good chance your phone is tracking your location—even with GPS services turned off. That's because, to receive service, our phones reveal personal identifiers to cell towers owned by major network operators. This has led to vast and largely unregulated data-harvesting industries based around selling users' location data to third parties without consent.

A glucose-COVID-19 hypothesis

In normal conditions, the lungs have the necessary immune defense to contain SARS-CoV-2 and avoid spread of the infection. If elevated, glucose impairs this primary defense system making ideal conditions for the SARS-CoV-2 to invade the pulmonary cells and spread into the rest of the body.

The 'Second Brain' in Your Gut Might Have Evolved Before The Brain in Your Head
The enteric nervous system (ENS) in our gut operates a lot like other neural networks in the brain and the spinal cord – so much so that it's often called the 'second brain'. Now a new study has revealed more about how exactly the ENS works.
Using a recently developed technique combining high-resolution video recordings with an analysis of biological electrical activity, scientists were able to study the colons of mice, and in particular the way that the gut moves its contents along.

One of the key findings was discovering how the thousands of neurons inside the ENS communicate with each other, causing contractions in the gastrointestinal tract to aid the digestive process. Up until now, it wasn't clear how these neurons were able to join forces to do this.

"Interestingly, the same neural circuit was activated during both propulsive and non-propulsive contractions.

The team found large bunches of connecting neurons firing to propel the contents of the colon further down the gut, via both excitatory (causing action) and inhibitory (blocking action) motor neurons.

The discovery means the ENS is made up of a more advanced network of circuitry, covering a wider section of the gut and involving a greater amount of different types of neurons working in tandem than had previously been thought.

Another important finding is that this activity is significantly different from the propulsion that's seen in other muscle organs around the body that don't have a built-in nervous system, such as lymphatic vessels, ureters, or the portal vein.

"The mechanism identified is more complex than expected and vastly different from fluid propulsion along other hollow smooth muscle organs," the researchers explain in their paper.

The team says it backs up the hypothesis that the ENS is in fact the 'first brain' rather than the second one – suggesting that it may have evolved in animals a long time before our actual brains took their current form.

https://www.nature.com/articles/s42003-021-02485-4

https://www.sciencealert.com/we-have-a-brain-like-system-in-our-gut...

Physicists Detect Strongest Evidence Yet of Matter Generated by Collisions of Light

According to theory, if you smash two photons together hard enough, you can generate matter: an electron-positron pair, the conversion of light to mass as per Einstein's theory of special relativity.

It's called the Breit-Wheeler process, first laid out by Gregory Breit and John A. Wheeler in 1934, and we have very good reason to believe it would work.

But direct observation of the pure phenomenon involving just two photons has remained elusive, mainly because the photons need to be extremely energetic (i.e. gamma rays) and we don't have the technology yet to build a gamma-ray laser.

Now, physicists at Brookhaven National Laboratory say they've found a way around this stumbling block using the facility's Relativistic Heavy Ion Collider (RHIC) - resulting in a direct observation of the Breit-Wheeler process in action.

But what do accelerated ions have to do with photon collisions? Well, we can explain.

The process involves, as the collider's name suggests, accelerating ions - atomic nuclei stripped of their electrons. Because electrons have a negative charge and protons (within the nucleus) have a positive one, stripping it leaves the nucleus with a positive charge. The heavier the element, the more protons it has, and the stronger the positive charge of the resulting ion.

The team used gold ions, which contain 79 protons, and a powerful charge. When gold ions are accelerated to very high speeds, they generate a circular magnetic field that can be as powerful as the perpendicular electric field in the collider. Where they intersect, these equal fields can produce electromagnetic particles, or photons.

"So, when the ions are moving close to the speed of light, there are a bunch of photons surrounding the gold nucleus, traveling with it like a cloud.

part 1

At the RHIC, ions are accelerated to relativistic speeds - those that are a significant percentage of the speed of light. In this experiment, the gold ions were accelerated to 99.995 percent of light speed.

This is where the magic happens: When two ions just miss each other, their two clouds of photons can interact, and collide. The collisions themselves can't be detected, but the electron-positron pairs that result can.

However, it's not enough to just detect an electron-positron pair, either.

That's because the photons produced by the electromagnetic interaction are virtual photons, popping briefly in and out of existence, and without the same mass as their 'real' counterparts.

To be a true Breit-Wheeler process, two real photons need to collide - not two virtual photons, nor a virtual and a real photon.

part 2

At the ions' relativistic speeds, the virtual particles can behave like real photons. Thankfully, there's a way physicists can tell which electron-positron pairs are generated by the Breit-Wheeler process: the angles between the electron and the positron in the pair generated by the collision.

Each type of collision - virtual-virtual, virtual-real and real-real - can be identified based on the angle between the two particles produced. So the researchers detected and analyzed the angles of over 6,000 electron-positron pairs generated during their experiment.

They found that the angles were consistent with collisions between real photons - the Breit-Wheeler process in action.

"We also measured all the energy, mass distributions, and quantum numbers of the systems. They are consistent with theory calculations for what would happen with real photons.

"Our results provide clear evidence of direct, one-step creation of matter-antimatter pairs from collisions of light as originally predicted by Breit and Wheeler."

The argument could be very reasonably made that we won't have a direct first detection of the pure, single photon-photon Breit-Wheeler process until we collide photons approaching the energy of gamma rays.

Nevertheless, the team's work is highly compelling stuff - at the very least, it shows that we are barking up the right tree with Breit and Wheeler.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.052302

Part 3

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