Friday 19 April 2024

Health and Wellness News: US study suggests that pretzel size affects eating behavior

 

US study suggests that pretzel size affects eating behavior


If you have hypertension, how big the salty snack is should be different than if you want to lose weight.  


By JUDY SIEGEL-ITZKOVICH, Jerusalem Post, April 15, 2024
https://www.jpost.com/health-and-wellness/article-797147  


 Researchers found that pretzel size affects the consumer's eating rate, with smaller sizes leading to a slower eating speed and smaller bites. (photo credit: Madeline Harper/Penn State)

With a quarter of daily calorie intake in the Western world – especially in Israel – derived from snacks that are not nutritious and even harmful to health, ways have to be found to encourage reducing their intake and replacing them with unprocessed and natural food. 

Researchers at Pennsylvania State University have found that the size of an individual snack piece not only influences how fast a person eats it, but also how much of it they eat. What they learned can have implications for helping people better understand how eating behavior impacts calorie and sodium intake.

The team of food scientists led by Madeline Harper, a graduate student in food science, working with Prof. John Hayes who was corresponding and director of the Penn State Sensory Evaluation Center, published their findings in the journal Appetite under the title “Unit size influences ad libitum intake in a snacking context via eating rate.”

They investigated how the size of pretzels influences eating behavior –overall intake, eating rate, bite size and how long they snacked – and found that people eat larger pretzels quicker with larger bites. They also found that while people ate smaller pretzels slower and with smaller bites and ate less overall, they still had higher intake of sodium (salt).

How the study was performed 

Seventy-five adults participated in the study, eating snacks three different times in the Sensory Evaluation Center. The oversized snack was about 2.5 servings of one of three sizes of pretzel – small, medium or large. To calculate eating rate and bite size, the researchers video recorded each snacking session, noting how many minutes each person spent snacking and their number of bites along with how much each participant ate in both weight and calories.

                                      Pennsylvania State University. (credit: WIKIPEDIA)

When participants were given the same amount of food, how much they ate — in both snack weight and calories — depended on unit size, with study participants consuming 31% and 22% more of the large pretzels compared to the small- and medium-sized pretzels, respectively. Size of the pretzel also influenced eating rate and bite size, with the largest pretzel size yielding the fastest eating rate and largest mean bite size.

The researchers also reported that, after accounting for eating behavior, the pretzel size alone did not significantly affect how much a person ate, suggesting the eating behavior the different pretzel sizes prompted was driving total intake. Their results suggest larger pretzel size induces a person to eat more quickly and take bigger bites.

Together, they proved that unit size influences intake by affecting eating behavior and that food characteristics such as unit size can be manipulated to moderate snack intake, Hayes explained. “Food structure – texture, size and shape – can be used to modulate eating behavior and food intake,” he said. “Food geometry, specifically unit size, is particularly useful for snack foods. We’re interested in how the material properties of foods can be harnessed to help people eat less without impacting their enjoyment.”

The relationship between pretzel size and sodium intake was obvious to the layman but previously overlooked by researchers, Harper explained. Eating more smaller pretzels likely results in higher consumption of salt. The smaller size has more surface area for the same weight, so the researchers hypothesize that more total salt on the surface means that a snacker would consume more sodium when eating them.

“So, we’re suggesting that if you’re trying to watch your calorie intake or are trying to reduce the amount that you’re eating in a snack, maybe a smaller pretzel would meet your needs better, because of the inherent way the size of the pretzel affects your eating rate,” Harper added. “But if you're more worried about hypertension from the amount of sodium you’re consuming, the larger pretzel would be better for you, because you’ll consume less salt even though you would consume more grams of pretzel.”

Crunchy Pretzel Perks: Unraveling the Benefits & Side Effects




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Deadly bacteria show thirst for human blood: Research outlines the phenomenon of bacterial vampirism

APRIL 16, 2024, by J. Babcock, Washington State U.

Washington State University researcher Arden Baylink holds a petri dish containing salmonella bacteria. Baylink and Ph.D. student Siena Glenn have published research showing that some of the world's deadliest bacteria seek out and eat serum, the liquid part of human blood, which contains nutrients the bacteria can use as food.
 Credit: Ted S. Warren, Washington State University College of Veterinary Medicine

Some of the world's deadliest bacteria seek out and feed on human blood, a newly-discovered phenomenon researchers are calling "bacterial vampirism."

A team led by Washington State University researchers has found the bacteria are attracted to the liquid part of blood, or serum, which contains nutrients the bacteria can use as food. One of the chemicals the bacteria seemed particularly drawn to was serine, an amino acid found in human blood that is also a common ingredient in protein drinks.

The research finding, published in the journal eLife, provides new insights into how bloodstream infections occur and could potentially be treated.

"Bacteria infecting the bloodstream can be lethal," said Arden Baylink, a professor at WSU's College of Veterinary Medicine and corresponding author for the research. "We learned some of the bacteria that most commonly cause bloodstream infections actually sense a chemical in human blood and swim toward it."

Baylink and the lead author on the study, WSU Ph.D. student Siena Glenn, found at least three types of bacteria, Salmonella enterica, Escherichia coli and Citrobacter koseri, are attracted to human serum. These bacteria are a leading cause of death for people who have inflammatory bowel diseases (IBD), about 1% of the population. These patients often have intestinal bleeding that can be entry points for the bacteria into the bloodstream.

Siena Glenn, a Washington State University Ph.D. student uses a high-powered microscope. Glenn, working with Assistant Professor Arden Baylink and colleagues, has published research showing that some of the world's deadliest bacteria seek out and eat serum, the liquid part of human blood. 
Credit: Ted S. Warren, Washington State University College of Veterinary Medicine

Using a high-powered microscope system designed by Baylink called the Chemosensory Injection Rig Assay, the researchers simulated intestinal bleeding by injecting microscopic amounts of human serum and watching as the bacteria navigated toward the source. The response is rapid—it takes less than a minute for the disease-causing bacteria to find the serum.

As part of the study, the researchers determined Salmonella has a special protein receptor called Tsr that enables bacteria to sense and swim toward serum. Using a technique called protein crystallography, they were able to view the atoms of the protein interacting with serine. The scientists believe serine is one of the chemicals from blood that the bacteria sense and consume.

"By learning how these bacteria are able to detect sources of blood, in the future we could develop new drugs that block this ability. These medicines could improve the lives and health of people with IBD who are at high risk for bloodstream infections," Glenn said.

Scientists Zealon Gentry-Lear, Michael Shavlik, and Michael Harms of the University of Oregon, and Tom Asaki, a mathematician at WSU, contributed to the research.



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There Could Be a Strange Link Between Menstrual Cycles And The Moon After All

16 April 2024, By J. COCKERILL

(Seventy Four/Getty Images)



People from many different cultures have long associated the human menstrual cycle with the phases of the Moon. Yet as uncanny as the similarities in average cycle time and the month might be, there's been little evidence of a link.

Now a research team from France and the US has found menstrual cycle rhythms are likely governed by the body's internal clock, rather than being a sum of processes intrinsic to the cycle itself.

What's more, there is a weak but significant association with the Moon's orbital period, hinting at a more fundamental biology once reliant on the timing of the tides.

It makes sense that so many cultures associate lunar and menstrual cycles; the Moon's phases repeat every 29.5 days, give or take about seven hours, while menstrual cycles have a mean length of 29.3 days, albeit with much variation between individuals.

Skeptics argue this perceived synchronicity is a mere coincidence, convenient to timekeeping, or perhaps just magical thinking. Though he never referred to menstruation specifically, in 1871 Charles Darwin proposed that lunar links may have an evolutionary origin: "In the lunar or weekly recurrent periods of some of our functions we apparently still retain traces of our primordial birthplace, a shore washed by the tides."

There's been evidence this is the case for species that rely on high tides for reproduction, like some fish and bivalves.

The researchers examined data on almost 27,000 menstrual cycles representing 2,303 European women and 721 North American women. Their analysis revealed something called 'phase jumps', in which menstrual phases 'jump' ahead to match up to a body clock external to the process.

"If the cycle lengthens, for any reason, this clock-based process adapts to quickly shorten it," neuroscientist Claude Gronfier, from The University of Lyon in France, told BBC Science Focus.

If the Moon did have any role in the length of human menstrual cycles, either as an evolutionary relic or in an ongoing influence, it would be more of a backseat driver with the body's own internal clock firmly at the wheel, the new study suggests.

The human body's 'clock' has a period of just over 24 hours, regardless of external factors such as the amount of time exposed to sunlight. Although it varies slightly between individuals, this circadian rhythm is highly stable for each person.

In the absence of sunlight – which resets the body clock to the 24-hour day – it can drift out of sync, as anybody with jetlag can attest to.

The researchers suggested that if an internal clock was involved in the menstrual cycle, then cycle lengths would be similarly stable within individuals, and have a narrow spread across a population.

While the study suggests this is the main mechanism behind menstrual timing, they did find a weak but statistically significant relationship between menstrual and lunar cycles, which varied depending on geography.

"The menstrual cycle began more often at the waxing crescent in Europe, whereas it was at the full moon in North America," the authors write.

While they don't have a clear explanation for this difference, they suggest it might be due to lifestyle differences (like sleep-wake cycles) between people from these continents.

"There is a lot of work ahead of us, and we hope that our colleagues embark with us on what could be a future area of circadian medicine," Gronfier told BBC Science Focus.

The team thinks their results could lead to potential fertility treatments, and says learning more about how genes regulate the menstrual cycle is key to understanding its chronobiology. A previous study found a specific gene variant linked to a hormone that affects cycle length.

However, this doesn't explain why cycles can phase jump based on previous cycles' duration, or how the body's internal clock could affect cycle length. More research with larger groups is needed to confirm these new findings and understand the underlying mechanisms.

"If the existence of an internal clock that controls the menstrual cycle is confirmed in further studies, then the medical treatment of ovulation disorders could use the chronobiological approaches," the authors write.


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Report finds high levels of pesticides in 20% of fruits, veggies

APRIL 18, 2024, by R. Foster


Nearly 20% of fresh, frozen and canned fruits and vegetables that Americans eat contain concerning levels of pesticides, a new report finds.

Pesticides posed significant risks in popular choices such as strawberries, green beans, bell peppers, blueberries and potatoes, the review from Consumer Reports found.

"One food in particular, green beans, had residues of a pesticide that hasn't been allowed to be used on the vegetable in the U.S. for over a decade," the report authors said in a news release. "And imported produce, especially some from Mexico, was particularly likely to carry risky levels of pesticide residues."

How likely? Sixty-five of 100 samples of the most contaminated produce were imported, with 52 of those samples originating from Mexico, the review found.

The majority of the highly contaminated produce were strawberries, typically the frozen variety, the report said.

Why? Because they grow low to the ground and are therefore more accessible to bugs, strawberries often top lists of foods contaminated with insecticides, CNN reported.

Meanwhile, nearly all the tested green beans were contaminated with acephate, an insecticide that is considered a "possible human carcinogen." The Environmental Protection Agency prohibited the chemical for use on green beans in 2011.

In response to the report, the Food Industry Association told CNN that "all pesticides go through an extensive review process by the U.S. Environmental Protection Agency [EPA] to ensure they are safe for human consumption and to establish tolerances, the maximum residue limit permitted on or in a food."

And the U.S. Food and Drug Administration is responsible "for monitoring and enforcing EPA's tolerances for pesticides in food, including foods imported into the U.S.," Hilary Thesmar, the association's chief science officer and senior vice president of food and product safety, told CNN.

Pesticides have been linked in studies to preterm births and neural tube defects. Exposure to pesticides has also been associated with heart disease, cancer and other illnesses.

Critics point to the EPA's lack of action as a key reason why pesticides are frequently found on produce, despite a growing amount of evidence that even low levels could be harmful, CNN reported.

"The EPA could certainly be doing a better job of setting more accurate safe limits based on the latest science," Alexis Temkin, senior toxicologist at the Environmental Working Group, told CNN. "Some of these pesticides require immediate, swift action by the EPA to consider these potential health risks more strongly."

Not all the news was bad, according to the report, which analyzed seven years of testing data from the U.S. Department of Agriculture on 59 common fruits and vegetables.

Pesticide levels were of little concern in nearly two-thirds of the foods included in the review, including nearly all of the organic ones, Consumer Reports said.

What can consumers do to reduce their risk of pesticide exposure?

Cleaning fruits and vegetables before eating does reduce pesticide levels, but there is "no method of washing produce that is 100% effective for removing all pesticide residues," according to the National Pesticide Information Center.

Starting with clean hands, wash and scrub produce under running water instead of soaking to remove the most pesticide residue, the center recommends.

Don't use soap, detergent or a commercial produce wash, however, as they have not been proven to be any more effective, FDA says. Dry the produce with a clean cloth or paper towel.

To reduce your risk of exposure even further, switch to organic produce whenever possible, Consumer Reports advised.


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Thursday 18 April 2024

Study finds world economy already committed to income reduction of 19% due to climate change

APRIL 17, 2024 ,by Potsdam Institute for Climate Impact Research

Credit: CC0 Public Domain

Even if CO2 emissions were to be drastically cut down starting today, the world economy is already committed to an income reduction of 19% until 2050 due to climate change, a study published in Nature finds. These damages are six times larger than the mitigation costs needed to limit global warming to two degrees.

Based on empirical data from more than 1,600 regions worldwide over the past 40 years, scientists at the Potsdam Institute for Climate Impact Research (PIK) assessed future impacts of changing climatic conditions on economic growth and their persistence.

"Strong income reductions are projected for the majority of regions, including North America and Europe, with South Asia and Africa being most strongly affected. These are caused by the impact of climate change on various aspects that are relevant for economic growth such as agricultural yields, labor productivity or infrastructure," says PIK scientist and first author of the study Maximilian Kotz.

Overall, global annual damages are estimated to be at 38 trillion dollars, with a likely range of 19–59 trillion dollars in 2050. These damages mainly result from rising temperatures but also from changes in rainfall and temperature variability. Accounting for other weather extremes such as storms or wildfires could further raise them.

Huge economic costs also for the United States and European Union

"Our analysis shows that climate change will cause massive economic damages within the next 25 years in almost all countries around the world, also in highly-developed ones such as Germany, France and the United States," says PIK scientist Leonie Wenz who led the study.

"These near-term damages are a result of our past emissions. We will need more adaptation efforts if we want to avoid at least some of them. And we have to cut down our emissions drastically and immediately—if not, economic losses will become even bigger in the second half of the century, amounting to up to 60% on global average by 2100. This clearly shows that protecting our climate is much cheaper than not doing so, and that is without even considering non-economic impacts such as loss of life or biodiversity."

To date, global projections of economic damages caused by climate change typically focus on national impacts from average annual temperatures over long-time horizons.

By including the latest empirical findings from climate impacts on economic growth in more than 1,600 subnational regions worldwide over the past 40 years and by focusing on the next 26 years, the researchers were able to project sub-national damages from temperature and rainfall changes in great detail across time and space all the while reducing the large uncertainties associated with long-term projections.

The scientists combined empirical models with state-of-the-art climate simulations (CMIP-6). Importantly, they also assessed how persistently climate impacts have affected the economy in the past and took this into account as well.

Countries least responsible will suffer most

"Our study highlights the considerable inequity of climate impacts: We find damages almost everywhere, but countries in the tropics will suffer the most because they are already warmer. Further temperature increases will therefore be most harmful there. The countries least responsible for climate change, are predicted to suffer income loss that is 60% greater than the higher-income countries and 40% greater than higher-emission countries," says Anders Levermann, Head of Research Department Complexity Science at the Potsdam Institute and co-author of the study.

"They are also the ones with the least resources to adapt to its impacts. It is on us to decide: structural change towards a renewable energy system is needed for our security and will save us money. Staying on the path we are currently on, will lead to catastrophic consequences. The temperature of the planet can only be stabilized if we stop burning oil, gas and coal."


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Indonesian 'Ring of Fire' Volcano Eruption Sparks Tsunami Alert, Evacuations

18 April 2024, By AFP

Mount Ruang spewing hot lava and smoke on April 17, 2024.
 (Center for Volcanology and Geological Hazard Mitigation/AFP)

A volcano erupted several times in Indonesia's outermost region Wednesday, with authorities raising the alert level to its highest point after the dome spewed a column of smoke more than a mile into the sky and forced hundreds to evacuate.

Mount Ruang, a stratovolcano in North Sulawesi Province, first erupted at 9:45 pm on Tuesday (1345 GMT) and four times throughout Wednesday, the country's volcanology agency said.

The alert level for the volcano, which has a peak of 725 metres above sea level, was then raised on Wednesday evening from three to four, the highest possible level in the four-tiered system.

"Based on the result of visual and instrumental observation that showed an increase in volcanic activity, Mount Ruang's level was raised from Level 3 to Level 4," Hendra Gunawan, head of Indonesia's volcanology agency said in a statement late Wednesday.

Authorities also widened a four-kilometre exclusion zone to six kilometres on Wednesday evening around the crater.

There were no reports of deaths or injuries, but more than 800 people were evacuated from two Ruang Island villages to nearby Tagulandang Island, which is located more than 100 kilometres (62 miles) north of provincial capital Manado, state agency Antara reported.

The volcanology agency said residents of Tagulandang must be evacuated outside the six-kilometre radius by Wednesday evening.

Gunawan also warned local residents to "be on alert for the potential ejection of rocks, hot cloud discharges and tsunami caused by the collapse of the volcano's body into the sea," the statement said.

Ruang's initial eruption late Tuesday pushed an ash column two kilometres (1.2 miles) into the sky, with the second eruption pushing it to 2.5 kilometres, Muhammad Wafid, head of the geological agency said in a statement earlier Wednesday.

The volcanology agency said Tuesday that volcanic activity had increased at Ruang after two earthquakes in recent weeks.

Indonesia, a vast archipelago nation, experiences frequent seismic and volcanic activity due to its position on the Pacific "Ring of Fire", an arc where tectonic plates collide that stretches from Japan through Southeast Asia and across the Pacific basin.


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Science News: Watching sports boosts well-being, offering positive psychological and neurophysiological benefits

Watching sports boosts well-being, offering positive psychological and neurophysiological benefits


Research led by Prof. Shintaro Sato reveals watching sports enhances well-being, benefiting society. Neuroimaging shows brain changes, impacting public health policy.


By JUDY SIEGEL-ITZKOVICH, Jerusalem Post, APRIL 17, 2024 
https://www.jpost.com/science/article-797543       


 Watching sports is good for your brain (17/4/2024) 
photo credit: WASEDA UNIVERSITY/SHINTARO SATO)
                 

If sitting in a stadium and watching soccer and other sports doesn’t lead to verbal and even physical violence between opposing teams, sports can serve as a source of enjoyment and relaxation. Observing games, especially among large crowds, goes beyond entertainment. It fosters a sense of community and belonging among audiences.

This sense of connection not only makes individuals feel good but also benefits society by improving health, enhancing productivity, and reducing crime. Although it is popularly recognized for its positive effects, existing studies on the relationship between watching sports and well-being offer only limited evidence.

Recognizing this gap, a team of researchers led by sports sciences Prof. Shintaro Sato of Waseda University in Japan embarked on a groundbreaking study that they have just published in the journal Sports Management Review titled “Watching sport enhances well-being: evidence from a multi-method approach.”

The team used a multi-method approach, combining secondary data analysis, self-reports, and neuroimaging measures to understand the connection between sports viewing and well-being in the general population.  “A significant challenge in well-being research is the subjective nature of measurement procedures, potentially leading to biased findings. Therefore, our studies focused on both subjective and objective measures of well-being,” Sato explained.

In their first study, the researchers analyzed large-scale publicly available data on the influence of watching sports on 20,000 Japanese residents. The results confirmed the ongoing pattern of elevated reported well-being associated with regular sports viewing. However, this study was limited by its inability to provide deeper insight into the relationship between sports consumption and well-being.

Sports viewing and brain rewards

                                           Brain scans (credit: SHUTTERSTOCK)


The second study – an online survey aimed at investigating whether the connection between sports viewing and well-being varied depending on the type of sport observed – encompassed 208 participants. The experiment exposed them to various sports videos, assessing their well-being both before and after viewing. The findings underscored that widely embraced sports, like baseball, exerted a more significant impact on enhancing well-being compared to less popular sports, such as golf.

However, the most groundbreaking aspect of this research emerged in the third study, in which the team employed neuroimaging techniques to scrutinize alterations in brain activity following sports viewing. Using multimodal MRI neuroimaging measurement procedures, the brain activity of 14 able-bodied Japanese participants was analyzed while they watched sports clips.

The results showed that sports viewing triggered activation in the brain's reward circuits, indicative of feelings of happiness or pleasure, and people said they watched sports more frequently showed greater gray matter volume in regions associated with reward circuits, suggesting that regular sports viewing may gradually induce changes in brain structures. 

“Both subjective and objective measures of well-being were found to be positively influenced by engaging in sports viewing. By inducing structural changes in the brain's reward system over time, it fosters long-term benefits for individuals. For those seeking to enhance their overall well-being, regularly watching sports, particularly popular ones such as baseball or soccer, can serve as an effective remedy,” Sato commented.

The authors wrote that their work has “profound implications and theoretical contributions to sports management literature. Existing literature has primarily focused on sports fans, but this study has taken into consideration a larger general population irrespective of their relationship to sports consumption and can contribute significantly to sports management practices and policymaking for public health.”     



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Wednesday 17 April 2024

Science News: NY University researchers explore the past of the coffee bean to create a high quality genome

 

NY University researchers explore the past of the coffee bean to create a high quality genome

Researchers unveil Arabica coffee's ancient origins and genetic secrets, aiding in creating climate-resistant varieties for the future amidst climate change threats.



                       Coffee genome research (photo credit: UNIVERSITY AT BUFFALO)


Coffee plants are very sensitive to their environment, which is why they are not grown everywhere. With climate change, will farmers who grow the precious beans always be able to do so? 

Researchers from the University at Buffalo declared that the key to growing coffee plants that can better resist climate change in the decades to come may lie in the ancient past. They have created what they say is the highest quality reference genome to date of the world’s most popular coffee species, Arabica, unearthing secrets about its lineage that span millennia and continents.

Their findings, just published in the prestigious journal Nature Genetics under the title “The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars,” suggest that this species developed more than 600,000 years ago in the forests of Ethiopia through natural mating between two other coffee species. The study found that the number of this plant waxed and waned throughout Earth’s heating and cooling periods over thousands of years before eventually being cultivated in Ethiopia and Yemen and then spread over the globe.

“We’ve used genomic information in plants alive today to go back in time and paint the most accurate picture possible of Arabica’s long history and determine how modern cultivated varieties are related to each other,” said the study’s co-corresponding author, biology Prof.  Victor Albert. 

Coffee giants like Starbucks and Tim Hortons exclusively use beans from Arabica plants to brew the millions of cups of coffee they serve everyday, yet, in part due to a low genetic diversity stemming from a history of inbreeding and small population size, Arabica is susceptible to many pests and diseases and can be cultivated only in a few places in the world where pathogen threats are lower and climate conditions are more favorable.

“A detailed understanding of the origins and breeding history of contemporary varieties are crucial to developing new Arabica cultivars better adapted to climate change,” Albert noted.

Arabica genome breakthrough



Cup of coffee (credit: INGIMAGE)


From their new reference genome, accomplished using cutting-edge DNA sequencing technology and advanced data science, the team was able to sequence 39 Arabica varieties and even an 18th century specimen used by Swedish naturalist Carl Linnaeus to name the species. 

“While other public references for Arabica coffee do exist, the quality of our team’s work is extremely high,” says one of the study’s co-leaders, Patrick Descombes, senior expert in genomics at Nestlé Research. “We used state-of-the-art genomics approaches - including long- and short-read high throughput DNA sequencing - to create the most advanced, complete and continuous Arabica reference genome to date.”

Arabica is the source of approximately 60% of the world’s total coffee products, with its seeds helping millions start their day or stay up late. However, the initial crossbreeding that created it was done without any intervention from humans, the researchers wrote.

Arabica formed as a natural hybridization between Coffea canephora and Coffea eugenioides, when it received two sets of chromosomes from each parent. Scientists have had a hard time pinpointing exactly when and where this event took place, with estimates ranging everywhere from 10,000 to one million years ago.

To find evidence for the original event, the researchers ran their various Arabica genomes through a computational modeling program to look for signatures of the species’ foundation. The models show three population bottlenecks during Arabica’s history, with the oldest happening some 29,000 generations -or 610,000 years - ago. This suggests Arabica formed sometime before that, anywhere from 610,000 to a million years ago. “In other words, the crossbreeding that created Arabica wasn’t something that humans did,” said Albert. “It’s quite clear that this event predated modern humans and the cultivation of coffee.”

Coffee plants have long been thought to have developed in Ethiopia, but varieties that the team collected around the Great Rift Valley that stretches from Southeast Africa to Asia, displayed a clear geographic split. The wild varieties studied all originated from the western side, while the cultivated varieties all originated from the eastern side closest to the Bab al-Mandab (“Gait of Tears”) strait that separates Africa and Yemen.

That would align with evidence that coffee cultivation may have started principally in Yemen, around the 15th century. Indian monk Baba Budan is believed to have smuggled the fabled “seven seeds” out of Yemen around 1600, establishing Indian Arabica cultivars and setting the stage for coffee’s global reach today. 

“It looks like Yemeni coffee diversity may be the founder of all of the current major varieties,” Descombes suggested. “Coffee is not a crop that has been heavily crossbred, such as maize or wheat, to create new varieties. People mainly chose a variety they liked and then grew it - so the varieties we have today have probably been around for a long time.”

“Our work has not been unlike reconstructing the family tree of a very important family,” Albert concluded.      

The History of the Coffee Bean






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Queen bumblebees surprise scientists by surviving underwater

APRIL 17, 2024, by L. GIVETASH


Researchers said more studies need to be done on whether other bumblebee species have a similar trait.

Bumblebees can surprisingly withstand days underwater, according to a study published Wednesday, suggesting they could withstand increased floods brought on by climate change that threaten their winter hibernation burrows.

The survival of these pollinators that are crucial to ecosystems is "encouraging" amid worrying global trends of their declining populations, the study's lead author Sabrina Rondeau told AFP.

With global warming prompting more frequent and extreme floods in regions around the world, it poses "an unpredictable challenge for soil-dwelling species, particularly bees nesting or overwintering underground", co-author Nigel Raine of the University of Guelph said in a statement.

Rondeau said she first discovered queen bumblebees could withstand drowning by accident.

She had been studying the effect of pesticide residues in soil on queen bumblebees that burrow underground for the winter when water accidentally entered the tubes housing a few of the bees.

"I freaked out," said Rondeau, who had been conducting the experiment for her doctoral studies. "It was only a small proportion... so it was not that big of a deal, but I didn't want to lose those bees."

To her "shock", she said, they survived.

"I've been studying bumblebees for a very long time. I've talked about it to a lot of people and no one knew that this was a possibility," she said.

She launched another experiment to better understand what happened.

Researchers placed 143 hibernating queen bumblebees in tubes—some with no water as a comparative group, some floating in water and some fully submerged using a plunger for a period ranging from eight hours to seven days, according to the study published in the journal Biology Letters.

Remarkably, 81 percent of the hibernating queens that were submerged not only survived seven days, but once returned to dry conditions remained alive eight weeks later.

The long-term impact on the bees' health and the effects it could have on a colony still needs further research, Rondeau noted.

The common eastern bumblebees used in the study are found in North America and are particularly hardy, not showing the same degree of population declines as other bee species, she said.

"So we are also wondering whether this resistance to flooding can be part of why they're doing so well," said Rondeau, now a postdoctoral fellow at the University of Ottawa.

The study would have to be replicated on other species of bumblebees to determine how common the trait is.

"But it's encouraging to know that at least (flooding) is not another big threat that we have to consider," she said.


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CO₂ worsens wildfires by helping plants grow, model experiments show

APRIL 16, 2024, by J. Bernstein, U. of California - Riverside

Figure shows that wildfires are much more responsive to the fertilizer effect of CO2 than to the greenhouse gas alone without considering this effect.
 Credit: James Gomez/UCR

By fueling the growth of plants that become kindling, carbon dioxide is driving an increase in the severity and frequency of wildfires, according to a UC Riverside study.

The worldwide surge in wildfires over the past decade is often attributed to the hotter, drier conditions of climate change. However, the study found that the effect of increasing levels of carbon dioxide (CO2) on plants may be a bigger factor.

"It's not because it's hotter that things are burning, it's because there's more fuel, in the form of plants," said UCR doctoral student in Earth and planetary sciences and study author James Gomez.

This conclusion, and a description of the eight model experiments that produced it, have been published in Communications Earth & Environment.

To convert light into food in a process called photosynthesis, plants require CO2. Burning fossil fuels for heat, electricity, and transportation is adding increasing levels of CO2 into the atmosphere. Plants use the extra CO2 to make carbohydrates that help them grow, leading to an increase in biomass that burns.

Certainly, heat waves and drought occur more frequently in today's climate than they did 50 years ago. These are conditions that cause plants to wither and die. As they dry out and die, they burn more easily. The models accounted for these effects on plants, as well as for different types of plants, and for the increase in atmospheric CO2.

"Warming and drying are still important fire factors. These are the conditions that make the extra plant mass more flammable," said UCR professor of Earth sciences Robert Allen.

The models analyzed by the research team all assumed an idealized 1% per year increase in atmospheric CO2 concentrations since 1850. The idealized increase is meant to isolate the effects of the greenhouse gas on wildfire activity.

"These experiments are mainly looking at the contribution of CO2 to changes in wildfire activity," Gomez said. "That's the only thing that's changing in these models. Other drivers of climate change and wildfire activity do not change through time," Gomez said. "This includes, for example, changes in other greenhouse gases like methane, as well as changes in land use."

Seasons are still important factors in promoting wildfires, and fires still occur more often during "fire seasons." Dry, windy conditions help spread the flames faster, increasing the size of the burned area. "However, our study shows the increase in fires during hotter seasons is driven by fuel load rather than an increase in the number of what some consider 'fire weather' days," Gomez said.

This means megafires can often happen outside of what is considered fire season. As an example, the biggest wildfire on record in Texas, with more than a million acres burned, occurred this past February.

The researchers hope that their results inspire others to conduct additional studies of the factors driving the increase in wildfires. In addition, they hope that policymakers recognize the urgent need to decrease the amount of CO2 that people release into the atmosphere.

"We do need to implement better fire control and have more prescribed burns to use up plant fuel. We need to get rid of the old stuff," Gomez said. "But the best way to decrease wildfires is to mitigate our carbon dioxide emissions. We need more emission control now."


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Tuesday 16 April 2024

Archaeology News: Archaeologists discover lost 1,800-year-old head of ancient Greek god Apollo

Archaeologists discover lost 1,800-year-old head of ancient Greek god Apollo

The head was believed to have been repurposed during the medieval period as a fountain.

By JERUSALEM POST STAFF, April 15, 2024
https://www.jpost.com/archaeology/article-797085


               1800-year-old head of ancient god Apollo.(photo credit: Greek Ministry of Education)


Archaeologists from the Aristotle University of Thessaloniki announced in late March that they had discovered a well-preserved head of the ancient Greek god Apollo in the city of Philippi, Greece.

The head, which was found by 15 archaeology students in September of 2023, is believed to date back to the 2nd or 3rd century CE.

While the statue was likely once worshipped as a representation of Apollo, it is believed to have been repurposed in the medieval period. The researchers theorized it had become part of a fountain in the town’s square in the 8th or 9th century.


             1800-year-old head of ancient god Apollo. (credit: Greek Ministry of Education)


Apollo, the twin brother of the virgin moon goddess of the hunt Artemis, was worshipped as the deity for the sun, music, medicine, art, prophecy, dance and archery.  

Other finds

Located near the head, a bronze coin dating back to the reign of emperor Leo VI (886-912) was found. 

A year prior to the find, researchers discovered a statue of the mythical hero Hercules nearby.      

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Closer look at the Menga dolmen shows it was one of the greatest engineering feats of the Neolithic

Dec 5, 2023 **REPORT** by B. Yirka , Phys.org

(a) Artistic representation of quarrying activities for the extraction the capstone C-5 in Cerro de la Cruz Quarry #2. 
Drawing: Moisés Bellilty under guidance of José Antonio Lozano Rodríguez and Leonardo García Sanjuán. 
(b) Aspect of the thickness and shape of the C-5 capstone, the support on part of the O-10 orthostat and the tumular structure. 
University of Malaga excavation. Ferrer-Marqués, 1984. Conjunto Arqueológico Dólmenes de Antequera.
 (c) Convex morphology of the top of the C-5 capstone and the thickness of the tumular structure.
 University of Malaga excavation. Ferrer-Marqués, 1984. Conjunto Arqueológico Dólmenes de Antequera. 
Credit: Scientific Reports (2023). DOI: 10.1038/s41598-023-47423-y

A team of archaeologists, geologists and historians affiliated with several institutions in Spain has found that the Menga dolmen represents one of the greatest engineering feats of the Neolithic. In their study, published in Scientific Reports, the group used new technology to learn more about the stone that was used to create the ancient burial site and to explore how wood and rope would have been used in its construction.

The Menga dolmen is an ancient burial mound located near Antequera, Málaga, Spain. It has been dated to approximately 5,700 years ago and is one of the largest known megalithic structures to be built in Europe. It was built into the top of a hill using large stones, the largest of which weigh more than 100 tons. In this new effort, the research team took a closer look at the composition of the stones used to build the burial mound, where they came from and how they were transported.

To learn more about the makeup of the stones, the research team used petrographic and stratigraphic analysis techniques, which showed that the stones were mostly calcarenites, a type of detrital sedimentary rock. In the modern age, they are known as soft stones due to their fragility. According to the researchers, such a soft type of rock would have been difficult to transport without causing damage—a finding that suggests a certain level of engineering sophistication.

(a) Geological map of tectonic jointing on DTM, showing the location of Menga and Viera and the likely quarrying areas at Cerro de la Cruz. 
(b) Stereographic representation of the groups of joints. 
(c) Overview of the tectonic fracturing present in quarry areas #2 and #3. 
(d) Groups of joints observed in Quarry #1.
 (e) Example of a possible discarded megalithic stone at Quarry #1. 
Credit: Scientific Reports (2023). DOI: 10.1038/s41598-023-47423-y

Moving and placing such large stones, they state, would have involved massive planning and engineering, particularly for the capstone, which, as its name implies, was laid across the top of the chamber to serve as a roof. The researchers say it weighs approximately 150 tons. They point out that placing such large rocks would have involved the use of scaffolds and ropes, and transporting them would have required level roads.

The research team also states that the burial ground was built in such a way as to point in a desired direction. Its position aligns with nearby mountains in a way that creates complex light patterns inside the chamber. They also found that the early engineers had devised a way to place stones at the edges of the burial chamber in interlocking fashion to channel away water seepage as a means of preventing erosion.


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