Challenging Long-Standing Climate Assumptions: Earth Is Getting Hotter, but Soil Is Getting Wetter

By HARVARD JOHN A. PAULSON SCHOOL OF ENGINEERING AND APPLIED SCIENCES,  MARCH 24, 2024

https://scitechdaily.com/challenging-long-standing-climate-assumptions-earth-is-getting-hotter-but-soil-is-getting-wetter/

Harvard University research finds that increased precipitation, not rising temperatures, is the key driver behind the rise in U.S. soil moisture levels during summers from 2011 to 2020, challenging assumptions about drying soils due to climate change. The study highlights the importance of accurate precipitation predictions and effective water management in agriculture amidst uncertainties in long-term soil moisture trends.
Study indicates that changes in rainfall patterns, rather than shifts in temperature, account for trends in soil moisture.

Soil moisture levels play a crucial role in influencing the speed at which wildfires expand, the rapidity with which hills transform into mudslides, and, notably, the efficiency of our agricultural systems. With the ongoing increase in temperatures attributed to anthropogenic climate change, there is a growing apprehension among scientists that soil conditions might become drier. Yet, interestingly, from 2011 to 2020, there was an observed increase in soil moisture across 57% of the United States during the summer months, traditionally the hottest period of the year.

Why did soil get wetter even as the planet got hotter?

A recent paper from Harvard University researchers found that precipitation, rather than temperature, overwhelmingly explains soil moisture trends. While it’s not surprising that more rain means wetter soil, the research challenges a long-standing assumption that increases in global temperatures will lead to drier soils.

“Atmospheric water has often been used as a proxy for drought, but this paper highlights distinctions between the hydroclimate of soils and the temperature and hydroclimate of the atmosphere,” said Peter Huybers, Professor of Earth and Planetary Sciences in the Faculty of Arts and Sciences and of Environmental Science and Engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences, and senior author of the paper.

The research team found that drying from increased temperature was largely balanced by CO2 fertilization, which allows plants to use water more efficiently. Both these effects are secondary relative to rainfall and tend to cancel each other out — leaving precipitation as the primary driver of soil moisture.

Challenges in Soil Moisture Measurement and Implications

One challenge in studying soil moisture is a sparsity of data and the frequent disconnect between satellite data and ground-level observations. The team compared ground-level observations between 2011 and 2020 — the short time period during which many soil moisture measurements are available across the United States — with satellite data and found a similar increase in soil moisture.

These findings highlight the importance of improving predictions of long-term changes in precipitation in response to climate change, especially in relation to food production.

“We don’t have very accurate measurements of long-term soil moisture, but the consequences of high temperatures for agricultural yields have a lot to do with water availability,” said Lucas Vargas Zeppetello, who was a Fellow at the Harvard University Center for the Environment and is first author of the study. “Plants are generally less sensitive to temperature if they have sufficient water, but in dry conditions, they can get in big trouble.”

Vargas Zeppetello is now an assistant professor at U.C. Berkeley.

“Our results suggest that reduced surface soil moisture is far from a foregone conclusion given the uncertainty in precipitation trends around the globe,” said Huybers. “With uncertainties in the interannual variability of rainfall and uncertainties in predictions of long-term rainfall, it’s virtually impossible to predict soil moisture in the coming decades.”

That uncertainty makes it difficult to predict growing conditions for crops, making it all the more important to focus on water management strategies, said Vargas Zeppetello.

Recommend this post and follow

The Life of Earth

https://disqus.com/home/forum/lifeofearth/

A decade of aphantasia research: What we've learned about people who can't visualize

Mar 27, 2024, by U. of Exeter

https://medicalxpress.com/news/2024-03-decade-aphantasia-weve-people-visualize.html

Credit: Pixabay/CC0 Public Domain

People who can't visualize an image in their mind's eye are less likely to remember the details of important past personal events or to recognize faces, according to a review of nearly 10 years of research.

People who cannot bring to mind visual imagery are also less likely to experience imagery of other kinds, like imagining music, according to new research by the academic who first discovered the phenomenon.

Professor Adam Zeman, of the University of Exeter, first coined the term aphantasia in 2015, to describe those who can't visualize. Since then, tens of thousands of people worldwide have identified with the description. Many say they knew they processed information differently than others but were unable to describe how. Some of them expressed shock on discovering that other people can conjure up an image in their mind's eye.

Now, Professor Zeman has conducted a review of around 50 recent studies to summarize findings in a field that has emerged since his first publication. The paper is titled "Aphantasia and hyperphantasia—exploring imagery vividness extremes" and is published in Trends in Cognitive Sciences.

Research indicates that aphantasia is not a single entity but has subtypes. For example, not everyone with aphantasia has a poor autobiographical memory or difficulty in recognizing faces, and in a minority of people, aphantasia appeared to be linked to autism. People who cannot visualize are more likely to have scientific occupations. Unexpectedly, although people with aphantasia can't visualize at will, they often dream visually.

Professor Zeman's review provides evidence that whether people have aphantasia or hyperphantasia—a particularly vivid visual imagination—is linked to variations in their physiology and neural connectivity in the brain, as well as in behavior. For example, listening to scary stories alters skin conductance in those with imagery, meaning people sweat—but this does not occur in people with aphantasia.

Aphantasia is thought to affect around 1% of the population, while 3% are hyperphantasic. These figures rise to around 5% and 10% with more generous criteria for inclusion. Both aphantasia and hyperphantasia often run in families, hinting at the possibility of a genetic basis.

Professor Zeman, who now holds honorary contracts at the universities of Exeter and Edinburgh, said, "Coining the term 'aphantasia' has unexpectedly opened a window on a neglected aspect of human experience. It is very gratifying that people who lack imagery have found the term helpful, while a substantial surge of research is shedding light on the implications of aphantasia.

"Despite the profound contrast in subjective experience between aphantasia and hyperphantasia, effects on everyday functioning are subtle—lack of imagery does not imply lack of imagination. Indeed, the consensus among researchers is that neither aphantasia nor hyperphantasia is a disorder. These are variations in human experience with roughly balanced advantages and disadvantages. Further work should help to spell these out in greater detail."

Recommend this post and follow

The Life of Earth

https://disqus.com/home/forum/lifeofearth/

Chuck's photo corner, Mexico, Mar. 30, 2024

Pics from our second last week here, just less than a week left to go.

Anik singing at Tlaquepaque trailer park and apartment complex.

these tree's bloom for weeks

charcoal cooked and lightly road dusted, taste super

I hear these are star fruit

the local Canadian name for these is crown of thorns, quite apt. I would say.

We were invited to this womans home to look at her stuff I took just a few pics

we thought it must be a shop but no it was he home

She had 5 or 6 urns of the ashes of relatives on one shelf, and a large wooden tuna over the stove amongst many many other things.

Thursday Market day in La Penita

The ceiling in the central dome building at the town square, in La Pineta

spring growth on this palm and the next palm over used as a hydro pole

A pineapple growing in a side street in La Pineta

growing on the warf in La Pineta

A frigat bird in the air over the beech, La Penita

Dawn out the gate on the way to the airport Friday

We took a different street walking home, it had so many flowers.

Cheers and be well

https://disqus.com/home/forum/lifeofearth/

Birth Rates Are Plummeting in Most Nations, And The World Isn't Prepared

30 March 2024, By J. COCKERILL

https://www.sciencealert.com/birth-rates-are-plummeting-in-most-nations-and-the-world-isnt-prepared

(Jonathan Kirn/Getty Images)


Human birth rates will continue to drop drastically over the coming century, and within just 25 years, over two-thirds of countries' populations will be in decline.

That's the finding of a new study published in The Lancet. The extensive team of international scientists behind the paper warns that governments must prepare for the massive changes we will face in the coming decades, as a result of these changes to global population patterns.

"These future trends in fertility rates and live births will completely reconfigure the global economy and the international balance of power and will necessitate reorganizing societies," says Natalia Bhattacharjee, a population statistician with the Institute for Health Metrics and Evaluation (IHME) in the US.

Back in 2018, previous studies found fertility rates were falling in half the world's populations, and the plummet continues.

By 2050, the new study forecasts, people living in 155 out of the 204 countries and territories included in the study will be having fewer babies than it would take to maintain a stable population.

The forecasts show that by 2100, that will increase to 198 countries and territories with birth rates lower than their death rates. In Bhutan, Bangladesh, Nepal and Saudi Arabia, rates will fall below one child per female. By that time, the only countries expected to have birth rates that exceed the level needed for population maintenance (at least two births per female) are Samoa, Somalia, Tonga, Niger, Chad and Tajikistan.

And if all that's the case, the authors write, then without strategic migration policies, the human population in places with low birth rates will inevitably shrink.

But is that so bad? In many countries, reduced birth rates are the result of better conditions for women and families in general.

"In many ways, tumbling fertility rates are a success story, reflecting not only better, easily available contraception but also many women choosing to delay or have fewer children, as well as more opportunities for education and employment," says senior author and biostatistician Stein Emil Vollset, also a member of the Future Health Scenarios forecasting team.

In the 1950s, there were just under five children born to each female, compared to just over two children to each female in 2021.

But the authors point out that the impact of such a drastic shift in the human population will also depend on how it is managed, and where people are located. At the moment, they say, we as a global community are not prepared for what's coming.

The study finds that the majority of children – three in four – will be born into low- and lower-middle income countries, over the coming decades.

In 2050, Chad and Niger are predicted to have the highest fertility rates worldwide, and by 2100, Samoa and Tonga are predicted to have the highest fertility rates.

By 2100, one in every two children born will come from Africa, which already contributed one third of the world's babies in 2021.

"The world will be simultaneously tackling a 'baby boom' in some countries and a 'baby bust' in others," Vollset says.

"As most of the world contends with the serious challenges to the economic growth of a shrinking workforce and how to care for and pay for aging populations, many of the most resource-limited countries in sub-Saharan Africa will be grappling with how to support the youngest, fastest-growing population on the planet in some of the most politically and economically unstable, heat-stressed, and health system-strained places on earth."

The authors say "ethical and effective immigration policies with global co-operation" will be crucial in managing the population crashes many countries are due to face.

"Once nearly every country's population is shrinking, reliance on open immigration will become necessary to sustain economic growth," Bhattacharjee says. "Sub-Saharan African countries have a vital resource that ageing societies are losing – a youthful population."

But the authors point out it will be important to ensure migration is not one-directional.

"Continued skilled worker migration to high-income, low-fertility economies – a concept referred to as brain drain – can also have devastating effects on the economies these workers leave behind," they write.

While there are some important limitations to the study – like the fact some of the more recent data is from weird COVID-19 times – the forecasts are based on key drivers of fertility – like education levels, contraception availability, child mortality, and living in urban areas – along with data going back to the 1950s, and had relatively high levels of certainty for all countries.

The research has come out of the Global Burden of Disease, Injuries, and Risk Factors Study 2021, and was funded by the Bill & Melinda Gates Foundation.

Recommend this post and follow

The birth of modern Man

https://disqus.com/home/forum/lifeofearth/

Innovative Nanogel Shown Effective in Treating Spinal Cord Injuries

By P. DI MILANO Feb. 22, 2024

https://scitechdaily.com/innovative-nanogel-shown-effective-in-treating-spinal-cord-injuries/

A recent study has introduced an innovative nanogel capable of delivering anti-inflammatory drugs directly to glial cells, showing promise in treating spinal cord injuries that lead to paraplegia or quadriplegia.

Innovative nanogels developed by researchers have shown effectiveness in targeting glial cells for the treatment of spinal cord injuries, offering a new avenue for therapeutic intervention.

In a study published in Advanced Materials, researchers Pietro Veglianese, Valeria Veneruso, and Emilia Petillo from Istituto di Ricerche Farmacologiche Mario Negri IRCCS in collaboration with Filippo Rossi of the Politecnico di Milano have demonstrated that an innovative nanovector (nanogel), which they developed, is able to deliver anti-inflammatory drugs in a targeted manner into glial cells actively involved in the evolution of spinal cord injury, a condition that leads to paraplegia or quadriplegia.

Challenges in Current Treatment Approaches

Treatments currently available to modulate the inflammatory response mediated by the component that controls the brain’s internal environment after acute spinal cord injury showed limited efficacy. This is also due to the lack of a therapeutic approach that can selectively act on microglial and astrocytic cells.

Nanogel – Scheme of selective drug treatment in the central nervous system. 

Credit: Politecnico di Milano – Istituto Mario Negri

Nanogel Development and Efficacy

The nanovectors developed by Politecnico di Milano, called nanogels, consist of polymers that can bind to specific target molecules. In this case, the nanogels were designed to bind to glial cells, which are crucial in the inflammatory response following acute spinal cord injury.

The collaboration between Istituto di Ricerche Farmacologiche Mario Negri IRCCS and Politecnico di Milano showed that nanogels, loaded with a drug with anti-inflammatory action (rolipram), were able to convert glial cells from a damaging to a protective state, actively contributing to the recovery of injured tissue.

Nanogels were shown to have a selective effect on glial cells, releasing the drug in a targeted manner, maximizing its effect, and reducing possible side effects.

Insights and Future Directions

“The key to the research was understanding the functional groups that can selectively target nanogels within specific cell populations,” explains Filippo Rossi, professor at the Department of Chemistry, Materials and Chemical Engineering ‘Giulio Natta’ at Politecnico di Milano. “This makes it possible to optimize drug treatments by reducing unwanted effects.”

“The results of the study,” continues Pietro Veglianese, Head of the Acute Spinal Trauma and Regeneration Unit, Department of Neuroscience at Istituto Mario Negri, “show that nanogels reduced inflammation and improved recovery capacity in animal models with spinal cord injury, partially restoring motor function. These results open the way to new therapeutic possibilities for myelolysis patients. Moreover, this approacch may also be beneficial for treating neurodegenerative diseases such as Alzheimer’s, in which inflammation and glial cells play a significant role.”

Recommend this post and follow

The Life of Earth

https://disqus.com/home/forum/lifeofearth/

Huge Study Confirms Viagra Cuts Alzheimer's Risk by Over 50%

25 March 2024, By M. MCRAE

https://www.sciencealert.com/huge-study-confirms-viagra-cuts-alzheimers-risk-by-over-50

(Douglas Sacha/Getty Images)


An FDA-approved pharmaceutical used to treat erectile dysfunction could soon be recommended as a therapy for decreasing the risk of Alzheimer's disease.

By analyzing medical insurance data alongside a laboratory investigation on the genetic and neurological effects of sildenafil – a drug sold commonly under the brand name Viagra – researchers in the US have validated the medication's potential in keeping critical proteins in nerve cells from tangling into a deadly mess.

Studies have repeatedly demonstrated enzyme blockers called phosphodiesterase (PDE) inhibitors not only have an ability to promote blood flow in the penis, but could prevent the neurodegeneration responsible for dementia.

This potential might not be all that surprising, given PDEs are known to be involved in nerve signaling pathways that influence neuroplasticity. Previous investigations on animal models have shown the PDE inhibitor sildenafil reduces the excessive phosphorylation of 'tau' proteins in nerve cells that causes them to form toxic tangles, helping improve cognitive health and memory.

Yet not all research has been so flattering, with some studies failing to notice an effect on the population level at all. And while the drugs may have an effect on a neurological level, the mechanisms behind this process still aren't fully understood.

Researchers in the US used cell cultures of neurons created from stem cells donated by Alzheimer's patients to map the metabolic and genetic activity behind sildenafil's therapeutic effects.

Following five days of treatment, the laboratory-grown neurons produced significantly lower levels of tau proteins with excess concentrations of phosphorus added, confirming sildenafil's knack for protecting brain cells.

A reading of the messages produced by the cells' DNA found hundreds of changes in the expression of genes, many involving the inflammation, breakdown in communication between nerves, and guidance of nerve cell structures.

While additional studies will be needed to pinpoint exactly how these subtle influences may be involved in the pathology behind Alzheimer's, understanding the main gene families affected by sildenafil provided a solid foundation for understanding why it works and perhaps why some brains develop Alzheimer's in the first place.

A second feature of the study used AI to look for signs of sildenafil working on a population level. Previous studies have used medical insurance data to find sildenafil can reduce the risk of Alzheimer's disease by around 60 percent.

Yet these relied on just a single insurance database, potentially missing out on variables that might reveal a different conclusion. What's more, these studies suggested patients being treated for high blood pressure in the lungs, or pulmonary hypertension (PH), didn't see the same drop in dementia risk.

The researchers included four treatments commonly prescribed for PH in their data analysis, not only confirming sildenafil decreased Alzheimer's risk by around 60 percent, but finding it reduced risk in people with pulmonary hypertension after all.

"After integrating this large amount of data computationally, it is rewarding to see sildenafil's effects in human neurons and real-world patient outcomes," says Cleveland Clinic biomedical informatician and co-first author Feixiong Cheng.

"We believe our findings provide the evidence needed for clinical trials to further examine the potential effectiveness of sildenafil in patients with Alzheimer's disease."

With sildenafil already given the FDA tick of approval for erectile dysfunction, demonstrating its safety and effectiveness in reducing Alzheimer's risk could provide health authorities with a quick means of addressing what looks to be a rising tide of dementia.

Aging populations around the globe can expect the number of individuals living with dementia to nearly double every 20 years, from just under 80 million at the end of this decade to nearly 140 million by mid-century.

If we already have a pill at hand that can keep these numbers down, research like this will be vital in proving its worth.

Recommend this post and follow

The birth of modern Man

https://disqus.com/home/forum/lifeofearth/

Health and Wellness News: Oral bacteria can speed up development of pancreatic cancer - study

 

Oral bacteria can speed up development of pancreatic cancer - study

The significant connection sheds light on a previously recognized link between oral health and pancreatic cancer.

By JUDY SIEGEL-ITZKOVICH, Jerusalem Post, MARCH 26, 2024

https://www.jpost.com/health-and-wellness/article-793790       

 Pancreas sections from control and P. gingivalis-infected mice. Control mouse showing a small pre-cancerous lesion (photo credit: Nussbaum Lab, Hebrew University)

Bacteria in the mouth, plaque that sticks to the teeth and gums, and shields pathogens don’t only cause tooth loss. 

They are known to raise the risk of rheumatoid arthritis, dry mouth, autoimmune Sjogren’s syndrome, heart disease, stroke, diabetes, and even eating disorders. 

Therefore, it is vital to create and maintain a healthy mouth by brushing, flossing, and other means to get rid of bacteria that cause gingivitis and periodontitis.

Now, a new study at the Institute of Biomedical and Oral Research of the Hebrew University-Hadassah Faculty of Dental Medicine unveils a significant connection between oral bacteria and the development of cancer in mice and sheds light on a previously recognized link between oral health and pancreatic cancer – one of the deadliest malignancies.

Proof of a link between oral bacteria and pancreatic cancer

Prof. Gabriel Nussbaum and his team recently published groundbreaking research in the journal Gut that uncovered a pivotal link between oral bacteria and the onset of pancreatic cancer in mice.

   Pancreas sections from control and P. gingivalis-infected mice. Mouse infected with P. gingivalis – pancreas shown full-blown pancreatic cancer. (credit: Nussbaum Lab, Hebrew University)

Their study delves into the intricate relationship between oral microbiota, including notably Porphyromonas gingivalis, and the acceleration of pancreatic cancer development, offering crucial insights into early detection, prevention, and potential therapeutic avenues.

They published their study in the journal Gut under the title “Oral bacteria accelerate pancreatic cancer development in mice.” Pancreatic ductal adenocarcinoma (PDAC) has been connected to the presence of Porphyromonas gingivalis, a prevalent anaerobic bacterium (that doesn’t need oxygen to live) known for its association with periodontal disease.

Based on epidemiological clues, Nussbaum's team embarked on a journey to elucidate the potential of P. gingivalis in driving the progression of pancreatic cancer.

Their research entailed a comprehensive examination of P. gingivalis translocation from the oral cavity to the pancreas using mouse models.

By introducing the bacterium to genetically engineered mice predisposed to PDAC, the team uncovered compelling evidence of accelerated cancer development.

Key findings from the study indicate that viable P. gingivalis was found in the pancreas of healthy mice after applying it to the gums, and prolonged exposure caused changes in the pancreas, affecting its microbial balance.

In addition, applying P. gingivalis orally sped up the progression from early pancreatic abnormalities to pancreatic cancer in mice with a specific genetic mutation. The research also showed that this genetic mutation helped P. gingivalis survive inside cells, and the bacteria supported the survival of pancreatic cancer cells even when conditions were tough.

Nussbaum and his colleagues’ discoveries emphasize a direct link between P. gingivalis and the development of pancreatic cancer in mice, offering significant insights into how this disease progresses. 

The bacteria migrated from the oral cavity to the rodents’ pancreas.

“The study underscores the significance of considering oral health in understanding and tackling pancreatic cancer,” said Nussbaum.

 “By exploring the role of bacteria like P. gingivalis, we’re not only shedding light on potential risk factors but also uncovering new avenues for intervention and treatment.”

The findings suggest that there’s a real possibility that gum disease could be connected to the risk of pancreatic cancer, stressing how bacteria directly affect this link. 

There is potential in focusing on bacteria within cells as a way to lower the risk of pancreatic cancer or to improve existing treatments for it,” the team concluded. “These insights open up avenues for future research and could lead to more effective strategies for preventing and treating pancreatic cancer.”

Epidemiological studies highlight an association between pancreatic ductal adenocarcinoma (PDAC) and oral carriage of the anaerobic bacterium Porphyromonas gingivalis, a species highly linked to periodontal disease. 

We analyzed the potential for P. gingivalis to promote pancreatic cancer development in an animal model and probed underlying mechanisms.

THIS PAGE WAS POSTED BY SPUTNIK ONE OF THE SPUTNIKS ORBIT BLOG

HTTPS://DISQUS.COM/HOME/FORUM/THESPUTNIKSORBIT-BLOGSPOT-COM/

PLEASE RECOMMEND THIS PAGE AND FOLLOW US

AT HTTPS://DISQUS.COM/HOME/FORUM/LIFEOFEARTH/              

Elephant hunting by early humans may explain proximity between extensive Paleolithic stone quarries and water sources

Mar. 26, 2024, by Tel-Aviv U.

https://phys.org/news/2024-03-elephant-early-humans-proximity-extensive.html

Illustration of elephant hunting using spears. 

Credit: Dana Ackerfeld

Archaeologists from Tel Aviv University have uncovered the mystery surrounding extensive Paleolithic stone quarrying and tool-making sites: Why did Homo erectus repeatedly revisit the very same locations for hundreds of thousands of years? The answer lies in the migration routes of elephants, which they hunted and dismembered using flint tools crafted at these quarrying sites.

The research, published in the journal Archaeologies, was led by Dr. Meir Finkel and Prof. Ran Barkai of Tel Aviv University's Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures

Prof. Ran Barkai explains, "Ancient humans required three things: water, food, and stone. While water and food are necessities for all creatures, humans relied on stone tools to hunt and butcher animals, as they lacked the sharp claws or fangs of other predators. The question is, why do we find rock outcrops that were used for the production of flint tools surrounded by thousands of stone tools, and next to them, rock outcrops containing flint that was not used for the production of tools?"

"A study of indigenous groups that lived until recently, with some still alive today, shows that hunter-gatherers attribute great importance to the source of the stone—the quarry itself—imbuing it with potency and sanctity, and hence also spiritual worship."

"People have been making pilgrimages to such sites for generations upon generations, leaving offerings at the rock outcrop while adjacent outcrops, equally suitable for stone tool production, remain untouched. We sought to understand why; what is special about these sites?"

For nearly 20 years, Prof. Barkai and his colleagues have been researching flint quarrying and tool-making sites in the Upper Galilee. These sites are characterized by large nodules of flint convenient for crafting and are located within walking distance of the major Paleolithic sites of the Hula Valley—Gesher Benot Ya'akov and Ma'ayan Baruch.

These sites boast thousands of quarrying and extraction localities where, until half a million years ago, in the Lower Paleolithic period, prehistoric humans fashioned tools and left offerings despite the presence of flint in other geological formations in various places.

Because elephants were the primary dietary component for these early humans, the Tel Aviv University researchers cross-referenced the database of the sites' distribution with the database of the elephants' migration routes and discovered that the flint quarrying and knapping sites were situated in rock outcrops near the elephants' migration paths.

"An elephant consumes 400 liters of water a day on average, and that's why it has fixed movement paths," says Dr. Finkel. "These are animals that rely on a daily supply of water, and therefore on water sources—the banks of lakes, rivers, and streams."

"In many instances, we discover elephant hunting and processing sites at 'necessary crossings'—where a stream or river passes through a steep mountain pass or when a path along a lakeshore is limited to the space between the shore and a mountain range."

"At the same time, given the absence of available means of preservation and the presence of predatory animals in the area, the window of opportunity for a group of hunter-gatherers to exhaust their elephant prey was limited. Therefore, it was imperative to prepare suitable cutting tools in large quantities in advance and nearby."

"For this reason, we find quarrying and knapping sites in the Upper Galilee located a short distance from elephant butchering sites, which are positioned along the elephants' movement paths."

Subsequently, the researchers sought to apply an adapted model from the one they developed in Israel to several sites from the Lower Paleolithic period in Asia, Europe and Africa, where such a "triad" exists. These included both sites where the hunted animals were elephants or mammoths, as well as later sites where other animals, such as hippos, camels, and horses, were the prey.

"It appears that the Paleolithic holy trinity holds true universally: Wherever there was water, there were elephants, and wherever there were elephants, humans had to find suitable rock outcrops to quarry stone and make tools in order to hunt and butcher their favorite megaherbivores," says Prof. Barkai.

"It was a tradition: For hundreds of thousands of years, the elephants wandered along the same route while humans produced stone tools nearby. Ultimately, those elephants became extinct, and the world changed forever."

Recommend this post and follow

The Life of Earth

https://disqus.com/home/forum/lifeofearth/

The Hidden Danger of Braking – More Harmful Than Exhaust?

By U. OF CALIFORNIA - IRVINE,  Mar. 26, 2024

https://scitechdaily.com/the-hidden-danger-of-braking-more-harmful-than-exhaust/

A study from the University of California, Irvine reveals that most particles released when vehicles brake are electrically charged, offering a potential method to reduce air pollution using electrostatic precipitators. Highlighting the health and environmental justice issues of non-exhaust emissions, the findings stress the importance of addressing brake emissions, especially in lower-income, traffic-heavy areas.

The work may aid in controlling an important source of air pollution.

Researchers have a limited understanding of the particles emitted into the air when a vehicle’s brakes are applied. However, there are indications that these particles could pose a greater health risk than the emissions from the tailpipe.

In a new study in Proceedings of the National Academy of Sciences, University of California, Irvine researchers show how most of these particles emitted during light braking carry an electric charge – something that could potentially be exploited to help reduce air pollution from vehicles.

“We found that up to 80% of aerosol particles emitted from braking are electrically charged, and that many of them are in fact highly charged,” said Adam Thomas, a doctoral candidate in the lab of Jim Smith, professor of chemistry, who led the study alongside UCI postdoctoral researcher Paulus Bauer.

To do the work, the team used a large lathe to spin a detached brake rotor and caliper. They then measured the electric charge of the aerosols emitted into the air and discovered the 80 percent figure.

“I was very surprised,” said Smith. “We were also surprised that this has not really been studied given how common cars are in human societies.”
Implications for Public Health and Environment

The research is part of a broader team effort at UCI to understand the public health impacts of non-tailpipe emissions in areas beset by car traffic, including many areas in Southern California.

“The toxicity and health effects of brake wear particles are largely unknown,” said Manabu Shiraiwa, professor of aerosol chemistry at UCI and one of the researchers behind the university-wide project. “Recent results from my lab indicate that they may induce oxidative stress, but more research is needed.”

The new study reveals a problem that may grow as electric cars become more and more common over the next several decades. Electric cars, Smith explained, are not truly zero-emission vehicles, so municipalities need to think about strategies to reduce emissions from brake use as well as tailpipes.

Addressing Brake Emissions

The team found that the percentage of charged particles emitted largely depended on the material makeup of brake pads. Because the particles carry an electric charge, this should make it relatively easy to remove from the air.

“If they are charged, they can be removed easily from the air before they have a chance to have an impact at all on health,” said Smith. “All you would need to do is to collect them with an electrostatic precipitator – a device that exposes the charged particles to an electric field and efficiently sweeps them away.”

The public health risk posed by brake emissions is not borne equally by a population – lower-income parts of cities tend to be more traffic-heavy than others, which creates an environmental justice issue wherein certain socioeconomic classes are more exposed to brake emissions than others.

According to Professor Barbara Finlayson-Pitts, Distinguished Emeritus Professor of chemistry and the principal investigator of the project at UCI, emissions from braking are not well-characterized but are potentially significant in high-traffic areas. “These areas are often in poorer communities and highlight an important aspect of environmental justice that has been largely overlooked,” Finlayson-Pitts said.

Recommend this post and follow

The birth of modern Man

https://disqus.com/home/forum/lifeofearth/