Hexbyte Glen Cove Before geoengineering to mitigate climate change, researchers must consider some fundamental chemistry

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Some scientists have proposed planetary-scale solutions to address climate change, such as geoengineering using sulfur compounds to create a sunshield in the upper atmosphere. New research suggests there’s a good deal more chemistry to understand before proceeding. Credit: Francisco laboratory

It’s a tempting thought: With climate change so difficult to manage and nations unwilling to take decisive action, what if we could mitigate its effects by setting up a kind of chemical umbrella—a layer of sulfuric acid in the upper atmosphere that could reflect the sun’s radiation and cool the Earth?

According to a new study in the Journal of the American Chemical Society, a collaboration among Penn scientists and two groups in Spain, in the stratosphere pose a challenge to generating sulfuric acid, making its production less efficient than might have previously been expected. Thus more groundwork exploring the of how sulfuric acid and its building blocks will react in the is required in order to confidently move forward with this climate geoengineering strategy, the researchers say.

“These fundamental insights highlight the importance of understanding the photochemistry involved in geoengineering,” says Joseph S. Francisco, an atmospheric chemist in Penn’s School of Arts & Sciences and a co-corresponding author on the study. “That’s critically important and it’s something that’s been ignored.”

Using sulfuric acid to blunt the sun’s rays as a means of curbing impacts is based on a natural phenomenon: When volcanoes erupt, the sulfur they emit creates localized—or sometimes even far-reaching—cooling clouds that filter the sun. But those clouds emerge in the troposphere, which ranges from the Earth’s surface to about 10 kilometers up. Geoengineering using sulfuric acid would happen a good deal higher, in the stratosphere, from about 10 to 20 kilometers above the planet.

Conditions change as the altitude increases. Notably, the air becomes drier, and the energy of the sun’s rays becomes stronger. In the new work, Francisco, his postdoc Tarek Trabelsi, and colleagues from Spain’s Rocasolano Institute of Physical Chemistry and the University of València partnered to explore how these variables affected the involved in making sulfuric acid.

The major inputs are (SO2), which reacts with hydroxyl radicals (OH), a kind of atmospheric “detergent,” to create HOSO2. HOSO2 reacts with oxygen to create sulfur trioxide (SO3), which then reacts with water vapor to create sulfuric acid. Aerosols formed from the sulfuric acid have the ability to reflect sunlight.

These reactions are well characterized; together, they are responsible for creating rain in the troposphere. But whether that chemistry would work in the stratosphere and achieve the same efficiency was unknown.

To find out, the team used —an approach that considers the ground, transition, and excited states of atoms and molecules—to consider how HOSO2 and SO3 would behave in the stratosphere’s conditions of high light and low humidity. Though geoengineering approaches factor in the ability of these two molecules to reflect sunlight, the researchers found that when HOSO2 is produced in the stratosphere, solar radiation causes the molecule to quickly photolyze, essentially breaking apart into its component parts, including sulfur dioxide, which is harmful to humans in high concentrations.

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Hexbyte Glen Cove Sri Lanka ends farm chemical ban as organic drive fails

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Sri Lanka has abandoned its quest to become the world’s first completely organic farming nation.

Sri Lanka abandoned its quest to become the world’s first completely organic farming nation on Sunday, announcing it would immediately lift an import ban on pesticides and other agricultural inputs.

The island country has been in the grips of a severe economic crisis, with a lack of foreign exchange triggering shortages of food, and other essential goods.

Authorities had already walked back restrictions on fertiliser imports last month for tea, the country’s main export earner.

But ahead of planned farmer protests in the capital, Sri Lanka’s agricultural ministry said it would end a broader ban on all agrochemicals including herbicides and pesticides.

“We will now allow chemical inputs that are urgently needed,” ministry secretary Udith Jayasinghe told the private News First TV network.

“Considering the need to ensure , we have taken this decision.”

Vast tracts of farmland were abandoned after the import ban, first introduced in May.

Shortages have worsened in the past week, with prices for rice, vegetables and other market staples having doubled across Sri Lanka.

Supermarkets have also rationed rice sales, allowing only five kilograms (11 pounds) per customer.

Farmers’ organisations had planned to march on the national parliament in Colombo on Friday to demand the import of essential chemicals to protect their crops.

President Gotabaya Rajapaksa had justified the import ban by saying he wanted to make Sri Lankan farming 100 percent organic.

The policy was introduced after a massive hit to the cash-strapped island’s economy in the wake of the Covid-19 pandemic, with tourism earnings and foreign worker remittances drastically falling.

Authorities attempted to save foreign exchange by last year banning a host of imported goods, including some food and spices.

Sri Lanka also shut its only oil refinery last month after running out of dollars to crude.



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Hexbyte Glen Cove Winged Gods and walking griffons: A plate with a depiction of Scythian Gods has been found in Middle Don

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Silverplate with a depiction of Scythian Gods and eagle head griffons. Credit: Institute of Archaeology RAS

Expedition members of IA RAS have found a unique plate depicting winged Scythian gods surrounded by griffons during their excavations of the burial ground Devitsa V in Ostrogozhsky District of Voronezh region. This is the first case of such a finding in the Scythian barrows on Middle Don. No other items depictions of gods from the Scythian pantheon have been found in this area.

“The finding has made an important contribution to our concepts of Scythian beliefs. Firstly, a particular number of gods are depicted at once on one item. Secondly, it has never happened before that an item with depicted gods has been found so far from the north-east of the main Scythian centers,” said the head of the Don expedition, Prof. Valeriy Gulyaev.

Burial ground Devitsa V—named after the neighboring village area—was found in 2000 by the Don archaeological expedition of IA RAS. The site is situated on the hill of the right bank of the river Devitsa and is a group of 19 mounds which are situated in two parallel chains stretched from west to east. However, the significant part of ancient barrows has already disappeared: the necropolis area belongs to an agricultural sector and is being actively plowed.

Since 2010 the site has been systematically studied by the specialists from the Don expedition of IA RAS. During the cemetery excavations, some great discoveries have already been made. In 2019 in barrow 9 a burial was found which held the remains of a woman-warrior and an old lady in ceremonial female headwear known as a calathus.

In a field season in 2021, the Don archaeological expedition continued studying the necropolis. Archaeologists started the excavation of mound 7 in the central part of the cemetery Devitsa V in the vicinity of barrow 9.

The main grave referred to the Scythian times and dated back to the 4th century BC was located almost under the center of one mound and was a wooden tomb of 7.5×5 meters. In ancient times it was covered with oak half beams which were held by the seventeen large oak pillars on the gravesides. This is the biggest grave among all found in Devitsa V necropolis.

The barrow had already been plundered in . The robbers laid a wide test pit and “cleaned” a central part of the burial including the skeleton. However, by the time of the plundering the roof of the tomb had already fallen and that is why in the mixture of soil and tree remnants on the gravesides some grave goods have been preserved. Found items completely match the main elements of the Scythian “triad.” Equipment, harness, and “animal style” artifcats were found in a warrior’s grave.

There was a skeleton of a man of 40-49 years old in the grave. Next to his head archaeologists found many small gold semi-sphere plates which were decorated the funeral bed. Along with the skeleton an iron knife and a horse rib (likely, the remains of the ceremonial food), a spearhead, and three javelin’s heads were found. The scientists have been able to reconstruct the length of the weapon relying on that the counterweights of the lower part of the polearm that have been remained untouched. The spear was about 3.2 meters long, and the javelines’ length was about 2.2 meters.

In the southeast corner of the grave were fragments of three horse harness items: horse-bits, girth buckles, iron browbands, as well as iron, bronze, and bone Scythian pendants. The archaeologists have also found six bronze plates in the shape of wolves with grin laws which were decorated with horse cheeks—two on each harness. Next to the horse harness was a cut jaw of a young bear which testifies, according to the scientists, to the bear cult at the Scythes of Middle Don. Apart from it a molded cup and a big, black-glazed vessel have been found in different parts of the tomb.

In the northeast part of the grave separate from other items and a few meters far from the skeleton a silver square nailed by many small silver nails to a wooden base was found. The length of the plate was 34.7 cm, with the width in the middle part 7.5 cm.

In the central part of the plate is a winged figure facing a Goddess of animal and human fertility. The Goddess is known as Argimpasa, Cybele. The upper part of her body is stripped, and there is headwear, likely a crown with horns, on her head. The Goddess is surrounded on both sides with the figures of winged eagle-headed griffons. Depictions of this type, where the traditions of Asia Minor and ancient Greek are mixed, are often found in excavations of the Scythian barrows of the Northern Sea region, the Dnieper forest-steppe region, and the Northern Caucasus.

The left side of the plate is formed by two square plates decorated with the depictions of syncretic creatures standing in a so-called heraldic pose (in front of each other, close to each other with their paws). From the right side, two round buckles are attached to the plate on each of which one anthropomorphic character with a crown on his head standing surrounded by two griffons is depicted. Who those characters are and which item was decorated by this plate remains an open issue.



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Hexbyte Glen Cove Are your kids keeping up at school?

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Credit: CC0 Public Domain

How a child learns is as individual as the child themselves. Yet with the pressures of large class sizes, decreases in school funding and, most recently, home-schooling, many teachers are struggling to keep track of their students’ performance.

Now, world-first research from the University of South Australia is prioritizing learning to ensure all children are better monitored and supported throughout their education.

Using current student data, the team is creating individual student learning profiles—real-time assessments of each student’s learning against curriculum requirements, as well as social and emotional wellbeing, , and study behaviors—all presented in an easy-to-access online ‘dashboard’.

The new learner profiles and dashboard are hoped to provide teachers with an easy-to-use, quick reference tool to ensure all students—especially disadvantaged students—are appropriately supported and positioned for success

It’s a timely study, especially given declining rates of literacy and numeracy in Australian schools across the past two decades.

Lead researchers, Dr. Rebecca Marrone and Dr. Vitomir Kovanović, with UniSA’s Centre for Change and Complexity in Learning (C3L), say the learner profiles have the potential to significantly improve the quality of teaching and learning in Australia.

“Strategies to improve teaching quality are paramount in Australia, particularly given the overall decline in reading and mathematics,” Dr. Kovanović says.

“Yet, as many parents will attest, student success does not only rely upon —it also embraces student interests, goals, and social and emotional wellbeing.

“For teachers, the challenge is often time and resources—while they strive to deliver the best teaching, one-on-one support is near impossible; this research makes it one step closer.

“By looking beyond static, traditional grade-based methods, and by using real-time student data across a range of measures, we’re able to create individual profiles for each student.

“These profiles will show how a student is learning at any point in time, and when they’re plotted onto our dashboard, will help teachers quickly identify which children need additional support or interventions, and precisely when they need them.

“In this way, teachers can respond to children’s needs in a timely and appropriate manner based on their individual . “

The team is currently working with several Australian schools to develop prototype learner profiles. Dr. Marrone says the goal is to help teachers and students without adding extra work.

“There’s no doubt that COVID-19 has imposed restrictions on so many aspects of our lives, and for a lot of schools, the response has been a quick shift to blended and online learning,” Dr. Marrone says.

“So, we now have far more data, collected in real time. But how many schools are leveraging this data?

“This project draws on all possible data sources to create single place for collated student information.

“This could seriously change the way teachers support students. And the added beauty of the tool is that it aims to alleviate teachers’ workloads, not add to them.”



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Hexbyte Glen Cove Study: COVID tech took a toll on work-from-home moms

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Credit: Pixabay/CC0 Public Domain

It’s no secret that being a work-from-home mom during the dawn of the COVID-19 pandemic was a drag. And those tech tools—video meetings and texting—designed to make remote work easier? They just added to the stress and exacerbated the mental health toll on burnt out moms trying to hold everything together.

That’s one major takeaway from a study published this week in the journal Communication Reports. Researchers surveyed 540 adults in May 2020 who had worked for up to 10 weeks remotely, and found that stress levels among women with children skyrocketed—likely because blurred work-life balance boundaries meant they took on the brunt of juggling homeschooling and alongside professional duties.

The results also reveal that video chats and texts tended to stress out remote workers, regardless of parental status and other factors including age, race, and education. Why? Researchers hypothesize that the extra visual cues needed to get points across via a video screen and expectations of immediacy when replying to texts contributed to fatigue. For working mothers, these two communication methods were especially burdensome because they hindered the ability to multitask.

The findings raise questions about the future of and ways to preserve employees’ , said lead researcher and UNLV communication studies professor Natalie Pennington.

“We did find progressively increased for women with more children, which really points to the juggling act—you’re trying to keep track of multiple kids and the job,” she said. “The answer to alleviating stress might be supporting the use of asynchronous communication, like email, compared to synchronous forms, like video chats and texting, to create the flexibility needed to better balance work and home. When real-time communication is needed, may be better suited to allow for multi-tasking.”

The study was conducted in collaboration with Michigan State University associate professor Amanda Holmstrom and University of Kansas professor Jeff Hall.



More information:
Natalie Pennington et al, The Toll of Technology while Working from Home during COVID-19, Communication Reports (2021). DOI: 10.1080/08934215.2021.1993947

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Hexbyte Glen Cove Scientists use machine learning to predict smells based on brain activity in worms

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The neurons of the worm function differently when tasting salt. Each circle represents a neuron, and the connections between the circles are synapses. The scientists used graph theory to group some neurons into modules, which are identified by their colors. The number of modules was reduced to 5 (from 7) when the salt stimulus was presented to the worm. This signifies that these neurons are particularly important when the animal tastes salt. Credit: Salk Institute

It sounds like a party trick: scientists can now look at the brain activity of a tiny worm and tell you which chemical the animal smelled a few seconds before. But the findings of a new study, led by Salk Associate Professor Sreekanth Chalasani, are more than just a novelty; they help the scientists better understand how the brain functions and integrates information.

“We found some unexpected things when we started looking at the effect of these sensory stimuli on and connections within the worms’ brains,” says Chalasani, member of the Molecular Neurobiology Laboratory and senior author of the new work, published in the journal PLOS Computational Biology on November 9, 2021.

Chalasani is interested in how, at a , the processes information from the outside world. Researchers can’t simultaneously track the activity of each of the 86 billion in a living human—but they can do this in the microscopic worm Caenorhabditis elegans, which has only 302 . Chalasani explains that in a simple animal like C. elegans, researchers can monitor individual neurons as the animal is carrying out actions. That level of resolution is not currently possible in humans or even mice.

Chalasani’s team set out to study how C. elegans neurons react to smelling each of five different chemicals: benzaldehyde, diacetyl, isoamyl alcohol, 2-nonanone, and sodium chloride. Previous studies have shown that C. elegans can differentiate these chemicals, which, to humans, smell roughly like almond, buttered popcorn, banana, cheese, and salt. And while researchers know the identities of the small handful of sensory neurons that directly sense these stimuli, Chalasani’s group was more interested in how the rest of the brain reacts.

The researchers engineered C. elegans so that each of their 302 neurons contained a fluorescent sensor that would light up when the neuron was active. Then, they watched under a microscope as they exposed 48 different worms to repeated bursts of the five chemicals. On average, 50 or 60 neurons activated in response to each .

By looking at basic properties of the datasets—such as how many cells were active at each time point—Chalasani and his colleagues couldn’t immediately differentiate between the different chemicals. So, they turned to a mathematical approach called , which analyzes the collective interactions between pairs of cells: When one cell is activated, how does the activity of other cells change in response?

This approach revealed that whenever C. elegans was exposed to sodium chloride (salt), there was first a burst of activity in one set of neurons—likely the sensory neurons—but then about 30 second later, triplets of other neurons began to strongly coordinate their activities. These same distinct triplets weren’t seen after the other stimuli, letting the researchers accurately identify—based only on the brain patterns—when a worm had been exposed to salt.

C. elegans seems to have attached a high value to sensing salt, using a completely different circuit configuration in the brain to respond,” says Chalasani. “This might be because salt often represents bacteria, which is food for the worm.”

The researchers next used a machine-learning algorithm to pinpoint other, more subtle, differences in how the brain responded to each of the five chemicals. The algorithm was able to learn to differentiate the neural response to salt and benzaldehyde but often confused the other three chemicals.

“Whatever analysis we’ve done, it’s a start but we’re still only getting a partial answer as to how the brain discriminates these things,” says Chalasani.

Still, he points out that the way the team approached the study—looking at the brain’s network-wide response to a stimulus, and applying graph theory, rather than just focusing on a small set of sensory neurons and whether they’re activated—paves the way toward more complex and holistic studies of how brains react to stimuli.

The researchers’ ultimate goal, of course, isn’t to read the minds of microscopic worms, but to gain a deeper understanding of how humans encode information in the brain and what happens when this goes awry in sensory processing disorders and related conditions like anxiety, attention deficit hyperactivity disorders (ADHD), autism spectrum disorders and others.

The other authors of the new study were Saket Navlakha of Cold Spring Harbor Laboratory and Javier How of UC San Diego.



More information:
Javier J. How et al, Neural network features distinguish chemosensory stimuli in Caenorhabditis elegans, PLOS Computational Biology (2021). DOI: 10.1371/journal.pcbi.1009591

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Hexbyte Glen Cove Phages kill dystentery-causing bacteria and reduce virulence in surviving bacteria

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Phages are viruses that infect bacteria and can also be used to treat human infections. However, as with antibiotics, bacteria can readily evolve resistance to phage attack, highlighting a key limitation to the use of phages as therapeutics. Now, researchers from Yale University have shown that the naturally occurring phage A1-1 kills Shigella flexneri, a major cause of dysentery in sub-Saharan Africa and southern Asia and selects for phage-resistant mutants with reduced virulence. The research is published in Applied and Environmental Microbiology.

That serendipitous finding results from the fact that the ‘s use of a particular surface receptor on the bacterium called OmpA, as a portal to enter and kill S. flexneri, means that bacteria that escape the phage’s attack will either lack OmpA receptors, or that any remaining receptors will have mutated in ways that reduce virulence.

“We sought to discover a phage that was naturally capable of binding to outer membrane proteins of S. flexneri responsible for virulent cell to cell spread of this pathogen in the human intestine, hypothesizing that evolution of phage resistance should alter, or eliminate, this virulence factor protein,” said Kaitlyn E. Kortright, a postdoctoral scientist at Yale.

This, said Kortright, is “a biomedically useful evolutionary tradeoff that improves upon standard phage therapy approaches.”

The researchers pursued phage therapy against S. flexneri because that bacterium was already resistant to conventional antibiotics. Additionally, this pathogen is active primarily in low-income countries, where antibiotics are expensive and often unavailable, and clean drinking water is scarce. Phages, she explained, “might even be useful for treating water sources, by selecting for avirulent S. flexneri.”

The investigators began this project not knowing whether or not a phage existed that can kill S. flexneri. They assumed “that such viruses had naturally evolved, and could be isolated from environmental samples,” said Paul E. Turner, the Rachel Carson Professor of Ecology and Evolutionary Biology at Yale. To increase the odds, “we chose to search in a geographic region renowned for its extreme microbial biodiversity: Cuatro Cienegas, Mexico. Clearly a longshot, but apparently a reasonable idea, because this effort was successful.”



More information:
Kaitlyn E. Kortright et al, Selection for phage resistance reduces virulence of Shigella flexneri, Applied and Environmental Microbiology (2021). DOI: 10.1128/AEM.01514-21

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Phages kill dystentery-causing bacteria and reduce virulence in surviving bacteria (2021, November 19)
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Hexbyte Glen Cove Urbanization not always bad for food and land use diversity

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Multi-color carrots and radishes at urban farmers’ market: Retailing fresh vegetables and fruit is a key function, as is raising nutrition and food-system awareness. Credit: Karl Zimmerer, GeoSyntheSES, Penn State

Widely accepted myths that urbanization negatively impacts food and land use biodiversity are incorrect, according to a team of researchers who developed a framework for evaluating this intersection. Their results could also affect nutrition and food insecurity in urban areas.

More than 50% of humanity currently lives in and by 2050 this will grow to 68%. Growing urbanization drives changes in climate, land use, biodiversity and the human diet, according to the researchers.

“We can’t simply assume that urbanization exclusively, negatively impacts food biodiversity,” said Karl S. Zimmerer, E. Willard and Ruby S. Miller Professor of Environment and Society Geography, Penn State, who directs the GeoSyntheSES Lab.

The framework, which was published today (Nov. 19) in One Earth, looks at the intersection of urbanization and agrobiodiversity—biodiversity in food production and consumption as well as agricultural ecosystems—in four different areas: land use; supply chains; and foodways; and and food retail.

Looking at urban and peri-urban land use, there are a wide variety of approaches that help food and nutritional biodiversity. On a city’s fringe, crop land, orchards and dairy farms can supply a range of products.

According to the researchers some U.S. metropolitan areas could become locally self-sufficient in eggs and milk, but only 12% and 16% in fruits and vegetables, respectively. However, in Hanoi, Viet Nam, urban and peri-urban agriculture provides 62% to 83% of vegetables and significant levels of pork and fish. Within a city, and peri-urban area gardens and farms of all sizes, whether they are public or private, roof top or pocket, add to the diversity of food available to residents.

“Most urbanization in coming decades will be based in Africa,” said Zimmerer. “Asian cities have already grown, but increases will be much higher in Africa. The interesting thing is Africa will be dotted by large, peri-urban and urban spaces with small farms and gardens. Nutrition and will be paramount.”

Karl S. Zimmerer seen researching supply chain diversity of agrobiodiverse dry legumes in a South Asian food market in the New York metropolitan area. Credit: Karl Zimmerer, GeoSyntheSES, Penn State

Because not all food in a city can come from the city or its surroundings, supply chains are very important. These supply chains are local, national and international.

“Food security in U.S. is higher when we have supply chains that are more geographically diverse,” said Zimmerer.

Zimmerer explained that currently, supply chains are very proprietary, and it is hard to get data because companies do not let information out, but that newly available datasets on commodity networks could be used in research.

According to the researchers, “national supply chains have been shown to drive increasingly standardized and biologically simplified crop and livestock raising, as well as to support pockets of diversified farming.” So, supply chains can be both good and bad depending on what they carry from where and the diversity of the products they carry. While less biodiverse food chains will still supply food to urban populations, they may not solve the problems of nutritional insecurity.

The third segment of the framework is influenced by economics and culture. Food access is extremely important and reports of food deserts in U.S. cities have spurred some actions. But according to Zimmerer, since the Green Revolution in the 1950s and 1960s—a push toward modern, mechanized agriculture in the developing world that focused on a few specific staple, commodity crops—poor populations have been pushed to consume a less diverse but cheaper diet in which traditional foods and agricultural practices were deemed outdated.

However, urban poor are often of varied ancestry and carry with them the foodways of their respective cultures, according to the researchers. These cultures and the foods they eat can diversify the foods available for all in the area. Access to a diversity of culturally varied foods can also increase nutritional security.

The final branch of the framework is urban infrastructure and food retail, which show both challenges and opportunities for accessible, healthy food. Retail possibilities in an urban context include supermarkets, grocers, convenience or corner stores, formal and informal urban open-air markets and food delivery, street vendors, restaurants and other eateries.

High-agrobiodiversity urban farming using ecological production techniques in Hanoi, Vietnam.x. Credit: Karl Zimmerer, GeoSyntheSES, Penn State / Penn State. Creative Commons

This variety of options supplies a fertile field for investigating how urban infrastructure and retail outlets provide access to urban residents. Some of these possibilities include using data collected from bar codes or restaurant web sites to track the food biodiversity within a city or urban area.

The researchers said they hope that using this framework and the interconnectedness of the urban peri-urban environment with agrobiodiversity will help debunk the myth of these two vital conditions as incompatible.

They noted that the act of urbanization can have an intermediate period when agrobiodiversity is low, especially among the urban poor.

Reduced food biodiversity is marked by simplified diets that reflect low-agrobiodiversity and cheap-food commoditization. Strengthening food biodiversity among the urban poor can improve the situation of food- and nutrition insecure populations, according to the researchers.

“We conclude the urbanization-agrobiodiversity nexus is a crucial new focus of interdisciplinary research to strengthen sustainable development and systems,” the researchers said.

Also working on this project as co-authors have been Edward C. Jaenicke, professor of agricultural economics, Penn State; Chris S. Duvall, professor and chair of geography and environmental studies, University of New Mexico; Leia M. Minaker, assistant professor, Department of Planning, University of Waterloo, Ontario, Canada; Thomas Reardon, University Distinguished Professor of Agricultural, Food and Resources, Michigan State University; and Karen C. Seto, Frederick C. Hixon Professor of Geography and Urbanization Science, Yale University.



More information:
Karl S. Zimmerer, Urbanization and Agrobiodiversity: Leveraging a Key Nexus for Sustainable Development, One Earth (2021). DOI: 10.1016/j.oneear.2021.10.012. www.cell.com/one-earth/fulltex … 2590-3322(21)00598-4

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Hexbyte Glen Cove Algae blooms, which can threaten drinking water and human health, pop up regularly and may increase

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Credit: Unsplash/CC0 Public Domain

Barges carrying mounds of coal toward St. Louis passed by Starved Rock at a snail’s pace, inching past yellow-orange trees and sandstone canyons. A bald eagle hovered above a path leading hikers toward Lover’s Leap. Near the Starved Rock Lock and Dam, a pinch point along the Illinois River, the water was dull and unremarkable.

But the area is home to a problem that taints waters throughout the state: toxic algae blooms.

In June, its surface was streaked with neon green. The bloom, one of dozens sampled this year throughout Illinois, contained levels of a potent toxin more than 30 times above the advised state recreational standard.

Blooms of cyanobacteria, or , happen when, given the right mix of conditions including temperature, sunlight and , the microscopic organisms proliferate to the extent that it sometimes looks like someone dumped paint in the water.

The rise of blooms appears to be connected to human-caused climate change. Along with nutrient overload from intense storms, warming air temperatures—and in turn warming water temperatures—can feed blooms.

The frequency of algae blooms is likely to increase, a Great Lakes climate assessment noted. And they come with a cost—whether through the price of water treatment, dog deaths or risks to human health.

Microcystin, the most prevalent toxin in Illinois waters and the one in the Starved Rock bloom, can cause skin rashes, diarrhea and coughing. More extreme exposure can lead to liver damage.

Illinois’ formal monitoring program for harmful algae blooms began in 2013, after an especially hot summer resulted in eye-popping levels of toxins. Today, the Illinois EPA routinely monitors sites including some public water supply intakes such as those in Lake Michigan, and also responds to reports of possible blooms, keeping an eye on regular offenders, including the shallow, calm area near Starved Rock.

“There’s always concern that you’re going to have a banner bad year. There’s always hope that you’re not going to find much,” said Gregg Good, surface water section manager with the Illinois EPA. “Hot, dry weather, you’re going to probably find more.”

Toxins hit ‘holy moly’ level

In Illinois, toxic blooms turn up in certain bodies of water nearly every year.

Algae blooms can be a nuisance, causing problems for organisms that depend on access to light, which blooms block, and oxygen, which blooms deplete. Researchers are still trying to figure out why only some blooms are toxic, and the conditions that might make toxin production more likely.

In the mid-2000s, as reports of blooms grew in the Midwest, the state began collecting water samples. Microcystin was found in about half of 366 samples between 2005 and 2008; nearly all were in the low range. But, given the right conditions, blooms could become more toxic, researchers warned.

Then came 2012—Illinois’ hottest year on record. From May through August, Illinois also saw its fourth driest period on record, according to National Oceanic and Atmospheric Administration data.

“It was a drought year, a lot of the nutrients were not taken up by corn crops,” Good said. “Big rainfalls in the fall, and a lot of nutrient runoff in the lakes.”

A primary driver of algae blooms is phosphorus, which can end up in waterways from sewage treatment plants, or after farm fertilizer and manure is washed away, especially during intense storms.

Candlewick Lake in Boone County, which was the discharge site of a wastewater treatment plant decades ago, turned up a microcystin level of 14,800 micrograms per liter, prompting a “holy moly” comment in one state presentation.

In Winnebago County, Westlake—a few miles from sewage plant discharge and adjacent to a golf course—had a microcystin level of 31,500 micrograms per liter—a “holy holy moly moly” result. The World Health Organization’s recreational marker for a high probability of adverse health effects was above 20 micrograms per liter.

In Illinois, microcystin levels jumping from the tens to the thousands garnered some attention.

“That was a big red flag,” Good said.

And other states had already created programs for blooms.

“For us to think that we were immune to harmful algal blooms in the state of Illinois was ridiculous, so we started up the program,” Good said.

The Starved Rock bloom occurred in one of nearly 70 water bodies sampled this year, from northern Lake to southern Johnson counties, according to Illinois EPA data. Toxic blooms have been confirmed as late as November in previous years.

This summer, in addition to microcystin, the agency tested for two neurotoxins for the first time; no significant levels were detected.

About a quarter of the water bodies sampled as of late October had microcystin concentrations greater than 20 micrograms per liter, with a handful having concentrations in the hundreds and thousands, but nothing close to 2012 levels.

Today, challenges involve continuing to get the word out.

“Certainly more and more people know about what a harmful algal bloom is now,” Good said.

‘A lot we don’t know’

Samples from Lake County—where 134 of 148 assessed lakes are classified by the state EPA as “impaired” for esthetic quality, aquatic life or fish consumption—account for a significant chunk of this season’s toxic blooms.

That’s largely due to excess phosphorus levels, said Mike Adam, deputy director of environmental health with the Lake County Health Department. Once a lake is on the list, it can be difficult for it to move off. Phosphorus can linger in soils for years.

About 40% of lakes nationally have too much phosphorus, according to the most recent EPA assessment. Cyanobacteria in lakes, along with the detection of microcystin, was also on the rise.

Generally, a good recipe for blooms seems to be heavy spring rain that washes in nutrients, and then warm, dry weather that cooks up cyanobacteria, Adam said. But even the lakes most prone to blooms don’t necessarily pose an annual problem.

“There’s still a lot we don’t know about how these blooms occur and the dynamics of them,” Adam said.

Scientists are studying blooms throughout the Great Lakes region, and trying to figure out why they’re surfacing in places as surprising as Lake Superior, one of the largest freshwater bodies in the world. Climate change appears to be a main driver.

In Illinois, scientists expect to see the state become warmer and wetter, with extremes including exceptionally , more intense rains and longer dry spells. Average daily temperature has already increased by as much as 2 degrees in much of the state, and an Illinois climate assessment found that warming of 4 degrees or more is possible by the end of the century, depending on different emissions scenarios.

Despite some hopeful developments that came out of the pivotal climate conference this month in Glasgow, some experts say staying within 1.5 degrees Celsius of warming—the global threshold scientists believe could lead to things getting significantly worse—is highly unlikely.

One concern with climate change in Illinois is that different species of algae may find the shifts amenable—meaning more species moving into Illinois that can potentially produce toxins.

“We’ve seen it with ticks and mosquitoes,” Adam said. “It’s going to happen, too, with algae.”

There are some efforts to engineer blooms, including at Campus Lake in Jackson County, a regular site for toxic cyanobacteria.

Jia Liu, associate professor at Southern Illinois University at Carbondale, is leading a team of student researchers experimenting with solar power and magnetic nanomaterials that could reduce the toxicity of blooms by degrading cyanotoxins and removing phosphorus through absorption.

The bloom this season lasted from early July through September, comparable to other years, Liu said.

Short-term and long-term solutions to clean up the lake have been considered. In part, Liu said, that’s because blooms can deter people from wanting to walk by a green lake or lower home values. And algae blooms are “related to the quality of life.”

Monitoring the Illinois River

Upstream of the Starved Rock Lock and Dam, there’s a connection to nutrients coming out of Chicago and its suburbs. That includes the wastewater of more than 5 million people, with occasional sewage overflows, and runoff from cities of paved surfaces. Downstream, the river’s slope flattens, and tributaries are largely surrounded by farmland, where nutrients in fertilizer and manure make their way into waters after a heavy rain.

While the algae bloom season in Illinois may be coming to a close, the drivers behind the green slicks are gaining strength. Illinois is not only missing bench marks for nutrient reduction, but nitrogen and especially phosphorus loads—the majority from agriculture—have increased significantly above a baseline period, according to the latest nutrient reduction strategy report for the state.

On a recent morning, Jim Duncker removed an algae tracker near the lock and dam ahead of the arrival of cooler temperatures, and checked on a probe collecting water data. A new system to monitor phosphorus and nitrogen in close to real-time was in place on a platform above the river.

“This site has had relatively frequent blooms in the last couple years, and so it was a site that’s of interest,” said Duncker, basin coordinator for the U.S. Geological Survey. “It’s still a ways downstream but there’s concern there, that if there were a major bloom that persisted, Peoria would probably have to address their water supply.”

Lakes have long been the focus of algae blooms, but rivers are not immune. A harmful bloom in the Ohio River in 2015 covered hundreds of miles of water.

The Illinois River basin, which includes nearly 30,000 square miles from southeast Wisconsin to northwest Indiana, carries the largest phosphorus load in the state and is among the sites chosen by the USGS for a major monitoring effort to improve water science.

The research could assist scientists in understanding harmful algae blooms.

The Illinois River basin involves a lot of people who use the water for a range of uses, said Jessica Garrett, a USGS hydrologist who studies harmful algae blooms. “We’ve got the barge traffic, we’ve got drinking water sources, we’ve got recreational uses.”

Among researchers’ questions are what turns a bloom toxic and how an algae community changes throughout an event. There are different species of algae, and different strains within species that may or may not have toxin-producing genes. By tracking metrics including the balance of nutrients, temperature, stream flow and the influence of storm events, scientists hope to follow blooms through their course.

“Some algae are a nuisance, or they make the water green, but there’s a distinction between that and then something that creates a harmful situation, either because it’s choking up intakes or motors, or because it’s producing toxins, or other deleter

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Hexbyte Glen Cove Evidence found of genetic evolution in Europeans over past several thousand years

Hexbyte Glen Cove

Credit: CC0 Public Domain

A team of researchers affiliated with several institutions in China has found evidence of natural selection based evolutionary changes to people living in Europe over the past two to three thousand years. In their paper published in the journal Nature Human Behavior, the group describes their comparative study of people living in the U.K. today, with those living across Europe over the past several thousand years.

Noting that few studies have been conducted with the goal of learning more about in people living in relatively , the researchers designed a study that was meant to learn more about how natural selection has impacted people living in Europe over the past several thousand years.

To that end, they obtained access to the U.K. Biobank and the data it holds, some of which is genetic. They also obtained similar data from other entities holding retrieved from the remains of people living in Europe over the past several thousand years. The team then selected 870 that have been identified as being associated with certain genes related to phenotype and compared those found in modern British people (most of whom have European backgrounds) with those found in people living across Europe over the past few thousand years.

In looking at the data, the researchers found evolution at work in 755 genes related to the traits they had selected over the past 2,000 to 3,000 years—and they included skin pigmentation, dietary traits and body measurements. All three traits were found to be under near constant selection pressure, leading to near constant changes to the genome.

They note that changes were expected due to the differences in exposure to ultraviolet light—the early migraters to Europe were known to have dark skin; over time, they became lighter. They also found changes related to consumption of vitamin D, heat regulation and body measurements. Such changes they note, were also likely due to changes in climate. The researchers also found that some expected changes had not come about—genetic factors associated with inflammatory bowel disease and anorexia nervosa, for example, had not changed much.

The research team acknowledges that their results are still preliminary as more detailed work is needed.



More information:
Weichen Song et al, A selection pressure landscape for 870 human polygenic traits, Nature Human Behaviour (2021). DOI: 10.1038/s41562-021-01231-4

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Citation:
Evidence found of genetic evolution in Europeans over past several thousand years (2021, November 19)
retrieved 20 November 2021
from https://phys.org/news/2021-11-evidence-genetic-evolution-europeans-thousand.html

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