Researchers analyze how the fungus that causes verticillium wilt attacks olive trees

APRIL 29, 2020, by Asociacion RUVID
https://phys.org/news/2020-04-fungus-verticillium-wilt-olive-trees.html

Credit: CC0 Public Domain

Researchers from the Universities of Valencia and Cordoba, as well as from the Institute for Sustainable Agriculture of the Spanish National Research Council (CSIC), have studied the fungus that causes verticilosis, a disease that kills millions of olive trees. Through the observation of the olive root microbiome, they conclude that verticillium wilt is driven by a wide community of microorganisms that unite to attack plants, making researchers rethink how to cope with it. The results have been published in the prestigious journal BMC Plant Biology.

The work has its origin in the Master's Degree Thesis of Luis F. Arias-Giraldo, who completed the Bioinformatics Master at the University of Valencia. This course was supervised by researchers from the Institute for Integrative Systems Biology (I2SysBio) Vicente Arnau and Wladimiro Díaz, and Carlos P. Garay from the CSIC.

Verticillium wilt is one of the most devastating pests for the olive grove and one of the main phytosanitary problems in the sector. The disease, also known as "Root rot," is caused by a fungus –Verticillium dahliae– that remains in infected soils, colonizes the roots and clogs the vascular system until the plant dies, producing effects similar to those of a severe drought.

Vicente Arnau, professor at the department of Computer Architecture and Technology, points out that the infection is analyzed from the point of view of systems biology: "We do not focus on the interaction between two species. We analyze how all the species in the ecosystem of the olive tree interact."

The study has shown that the infection, for which there is no effective cure, is much more complex than was previously thought. The work has studied the dynamics of the microbiome of infected roots and concludes that the infection process involves many more contenders. Although the disease is initially directed by the verticillium fungus, it is not driven by a single species, but by a whole community of microorganisms that attack the tree.

The researcher from the Department of Biochemistry and Molecular Biology of the University of Córdoba Antonio Rodríguez Franco points out that the results suggest that the wilting of the olive tree by verticillium wilt "must be understood as a biological process of systems in which a complex interaction takes place."

According to the investigation, there are several fronts that occur in this type of microscopic warfare declared by the verticillium, but furthered by other organisms. As Arnau explains, "during the infection there is a biological succession of different types of parasites that could explain the parasitic alternations observed and described in many infectious systems."

Various types of fungi, bacteria, and protozoa act as a consortium to attack the tree. A series of opportunistic microbes, such as nematodes and amoebae, also come into play, which, although they do not initially participate in the infection, feed on the substances that the olive tree defenses generate to counteract the attack. Finally, the beneficial fungi that until now have maintained a symbiotic relationship with the roots of the tree change sides and become harmful to the plant itself.

This is, broadly speaking, the dynamics of a contest whose final result is the withering of thousands of olive trees in the Mediterranean basin, and which has been detailed after analyzing RNA samples and carrying out a metatranscriptomic study of different samples.

The results, according to the article, could contribute to focus future treatments to alleviate a disease that has increased in recent years due to the intensification of plantations in infected soils. At the moment, however, there are still several question marks to be resolved, such as the genes involved in the plant's defense processes and revealing why some olive species are immune to infection.

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Algae in the oceans often steal genes from bacteria

APRIL 29, 2020, by Rutgers University
https://phys.org/news/2020-04-algae-oceans-genes-bacteria.html

The diatoms in this image are members of the CRASH lineage that have stolen many genes from bacteria. CRASH species have become dominant phytoplankton in both marine and freshwater environments. Credit: Julia Van Etten

Algae in the oceans often steal genes from bacteria to gain beneficial attributes, such as the ability to tolerate stressful environments or break down carbohydrates for food, according to a Rutgers co-authored study.

The study of 23 species of brown and golden-brown algae, published in the journal Science Advances, shows for the first time that gene acquisition had a significant impact on the evolution of a massive and ancient group of algae and protists (mostly one-celled organisms including protozoa) that help form the base of oceanic food webs. These photosynthetic species produce about 70 percent of the oxygen we breathe and some of them, such as diatoms, are responsible for about 45 percent of global primary production of organic matter.

"The vast group of species called CRASH, including algae such as diatoms and dinoflagellates, as well as members of the group (alveolates) that includes the malaria parasite and another group (oomycetes) that includes the potato blight pathogen, creates and consumes immense amounts of organic matter," said corresponding author Debashish Bhattacharya, a distinguished professor in the Department of Biochemistry and Microbiology in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "There are hundreds of thousands of CRASH species and they have thrived on Earth for more than a billion years."

The scientists, led by researchers at the Chinese Academy of Fishery Sciences, created a massive genomic dataset of more than 524,000 protein sequences from 23 CRASH species and used sophisticated methods to analyze the data.

The results showed that gene stealing or acquisition (known as horizontal gene transfer) varies substantially among different CRASH species, with 0.16 percent to 1.44 percent of their genes (an average of 1 percent) coming from bacteria.

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Study suggests elephants may get drunk naturally after all

REPORT APRIL 29, 2020 , by Bob Yirka , Phys.org
https://phys.org/news/2020-04-elephants-drunk-naturally.html

Protein-altering changes in ADH7 along with evolutionary relationships and diets of species included in the analyses. Credit: Biology Letters (2020). DOI: 10.1098/rsbl.2020.0070

A team of researchers at the University of Calgary has found that variations in ethanol metabolism abilities in different species may account for the "myth" of natural animal intoxication. In their paper published in the journal Biology Letters, the group describes comparing mutations in the ADH7 gene in multiple species and what they found by doing so.

For many years, there has been anecdotal evidence of wild animals getting drunk and behaving badly after consuming fermented fruits and berries. One notorious example was of elephants consuming fruit from the malura tree after it fell and fermented. Herds were described as behaving erratically, sometimes crashing through villages after having abandoned their usually polite demeanor. But back in 2005, a team of researchers from the University of Bristol appeared to discredit such stories with a study in which they claimed to have found evidence that elephants were so large that it would take more fruit than they could consume to make them drunk. In this new effort, the researchers suggest that the team at Bristol forgot to account for a major contributing factor to drunkenness—how well a given animal is able to metabolize alcohol.

The work involved looking at the gene ADH7—it is present in a wide variety of animals. Its purpose is to instigate the production of enzymes that metabolize ethanol. Prior research has shown that most primates have an ADH7 mutation that allows them to metabolize ethanol more efficiently than those without it. It is believed the mutation persisted because it allowed primates to consume large amounts of fermented fruits and berries without getting too drunk to function. Notably, other mammals such as bats (which also eat a lot of fruits and berries) have a similar mutation—flying while drunk would not turn out well.

The researchers looked at ADH7 in 85 mammals and found that many of them, such as horses, cows and elephants, do not have the mutation, and are thus not nearly as good at metabolizing ethanol. This suggests that if such animals were to consume fermented fruits, they would become intoxicated much more easily than animals that do have the mutation. Thus, they suggest it is possible that elephants at times become inebriated, and because of that, may behave out of character.

Explore further:  Study shows pre-human ancestors adapted to metabolize ethanol long before humans learned about fermentation

https://phys.org/news/2014-12-pre-human-ancestors-metabolize-ethanol-humans.html

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How family stories help children weather hard times

APRIL 30, 2020, by Emory University
https://medicalxpress.com/news/2020-04-family-stories-children-weather-hard.html

Credit: CC0 Public Domain

In times of great stress, stories sustain us, says Robyn Fivush, director of the Family Narratives Lab in Emory's Department of Psychology.

Family reminiscing is especially important, says Fivush, who is also director of Emory's Institute for the Liberal Arts. When children learn family stories it creates a shared history, strengthens emotional bonds and helps them make sense of their experiences when something senseless happens—like the current global pandemic.

"When we don't know what to do, we look for stories about how people have coped in the past," Fivush says. "You can see that happening in the media now, in articles comparing today to historical events, like the 1918 flu pandemic and 9/11."

She sums up the 9/11 narrative in the United States: "A horrific event happened; we were attacked. But we came together as a nation, persevered and rose back up together."

Such narratives help build a shared capacity for resilience. "That's true for nations and it's true for families," Fivush says.

Over decades of research, Fivush and Emory psychologist Marshall Duke developed a scale to measure how much children know about their family histories. Using this scale, they conducted a study that began just before 9/11 and continued for two years. "We found that in families that talked in more coherent and emotionally open ways about challenging family events with 10- to 12-year-olds, the children coped better over the two-year period than in families telling less emotionally expressive and coherent stories about their challenges," Fivush says.

The families in the study were all comparable, middle-class, two-parent households.

Standardized measures showed that children in the families that told the more coherent family narratives had better self-esteem, higher levels of social competence, higher quality friendships, and less anxiety and stress. They also had fewer behavioral problems, as reported by parents.

Tips for telling family stories
For families under quarantine together, opportunities abound to weave family stories into conversation, Fivush says. The stories need to be tailored to different ages, she adds, so that children are emotionally and cognitively able to understand them.

Elementary school children, for example, are not ready to digest complex family stories. "With younger kids, it's really more about helping them structure their own experiences into stories that help them process their feelings," Fivush says. "You want to start by asking them non-judgmental, open-ended questions like: 'Why do you think you were upset yesterday? What could you have done to make yourself feel better? What can we do about this?'"

She uses an example of a little girl who left her favorite storybook at her school and was worried that it wasn't going to be there when she went back. A mother could tell a story about how she left a favorite toy somewhere when she was little but later her father took her back and they found it.

"Tell them a story from your own life that provides a model for how everybody forgets things, but you can get them back," Fivush says. "Or, 'My brother used to tease me a lot, too. But now he's your Uncle Bill and we love each other.' Parents are identity figures. Little kids are fascinated by stories about their parents when they were little."

Ultimately, the goal is to help children construct a coherent story that validates their feelings while helping them think of resolutions.

"Particularly with very young kids, don't make assumptions about what they may be upset or sad about," Fivush says. "You may be surprised. Stay open to what your children of all ages may be experiencing."

Middle school children are starting to have more of an ability to understand the bigger picture. "By the age of 10, children are thinking in the abstract and because of that, they are likely to be anxious about the future," Fivush says.

By this stage, children begin to understand stories on a deeper level. It's not that every story needs a happy ending or a silver lining, Fivush stresses. "You can explain to your child, 'We don't know yet how this story is going to end but let me tell you about some challenging times I got through, or your grandparents got through.'"

Examples of family members—who preserved by simply putting one foot in front of the other and by maintaining loving bonds—reassure children that their family will also find a way to get through a situation.

When they reach adolescence, children are especially vulnerable. "High school is a time when children start to really think about themselves as a person and what their life is going to be like," Fivush says. "They are mulling big questions, like 'Who am I? What are my passions?' And now the pandemic has pulled the rug out from under them."

By the age of 16, parents can start talking to a teen-ager about their own vulnerabilities as people and as parents. "Emphasize how you can build strength together, as a family," Fivush says. She suggests finding ways of giving teen-agers a role in supporting younger children in positive ways.

"Human beings are really altruistic and empathetic. We feel good when we help other people, particularly people that we love," Fivush says. "That's going to make every family member feel better about themselves and about each other."

Silly, funny family stories are also valuable, along with small touchpoints about the past that emerge spontaneously, Fivush says. "When you're cooking together with your children it's a perfect time to say, 'When I was a little girl, my mother taught me how to cook this dish. We used to have post roast every Friday and I would peel the carrots.'"

Adolescents are especially hungry for these kinds of stories, she adds. "If they roll their eyes, so be it, they're still listening," Fivush says. "It's the really mundane, everyday stories that reassure them that life is stable. It provides a sense of continuity, of enduring relationships and values. They need to know that they come from a long line of people who are strong, who are resilient, who are brave. And who can cook. The definition of who they are is not just something independent and autonomous, spun from nowhere. It's embedded in a long, intergenerational family story."

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Scientists Report Terrifying Ice Lumps That Could Be The Largest Hailstones Recorded

TESSA KOUMOUNDOUROS      30 APRIL 2020
https://www.sciencealert.com/this-megachonker-of-a-hail-stone-may-have-smashed-size-records

One of the hailstones from the storm in Argentina. (Victoria Druetta)

The hailstone is so massive it even stunned meteorologists.

"It's incredible," said meteorologist Matthew Kumjian from Penn State University in the US. "This is the extreme upper end of what you'd expect from hail."

The hefty ice lump smashed down from a supercell thunderstorm in Argentina two years ago, in the heavily populated town Villa Carlos Paz. In a recently published study, Kumjian and colleagues have concluded the hailstone is possibly the largest ever recorded - estimated to be up to 23.7 centimetres (over 9 inches).

However, as its dimensions were only gleaned from video evidence (below, 11 seconds in), and not direct measurements, they can't conclusively say it's the largest to be recorded.

Another hailstone from the same storm, recorded by local Victoria Druetta, came in at 18 centimetres (7.1 inches), after she saw chunks of it smash off during the impact of its landing.

Such horrific hailstones require special conditions - massive storms with powerful updrafts to keep them aloft long enough to pack on that weight. They start as raindrops sucked above freezing altitudes in a storm, and as they're tossed about up there, layers of supercool liquid water freeze onto them - the twists and turns moulding their lumpy lobed structures.

Such updrafts and windfields that twist and strengthen with height are promoted by warm and humid conditions, and radar information from this recent study showed this large hail fell close to where the main updraft occurred.

The examined hail also showed substantial wet growth, which occurs in the lower part of hail growth zones within the storms, suggesting the updraft there must be particularly strong for these giants to obtain their size.

As fascinating as this may be from a safe distance, hail of course is also extraordinarily dangerous, and more so the larger it gets.

"Hail can cause significant damage to property and agriculture, as well as injuries or even deaths," the researchers wrote in their paper.

They proposed officially classifying hailstones larger than 15 centimetres (6 inches) as "gargantuan", to help warn us all of their damaging potential.

"Anything larger than about a quarter in size can start putting dents into your car," Kumjian said. "In some rare cases, 6-inch hail has actually gone through roofs and multiple floors in houses. We'd like to help mitigate the impacts on life and property, to help anticipate these kinds of events."

The team searched for warning signs leading up to the hailstorm but found a "lack of indications of an extreme event in the pre-storm environment, numerical model forecasts, or radar imagery collectively," and pointed out we need a lot more research in this area.

With predicted increases in the severity of thunderstorms in the future, understanding the dynamics of these giant stones of ice may soon become more critical. So far, research on future hailstorms suggests some areas may see increases in hail frequency while others a decrease, but that there will likely be a shift from small to large hailstones occurring with increasing global temperatures.

Penn State meteorologist Rachel Gutierrez explains volunteers can help scientists better understand the risks of hailstorms by reporting and providing accurate recordings of gargantuan hailstones, including the time and location of its fall and its weight.

This research has been published in the Bulletin of the American Meteorological Society.

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How the heart affects our perception

APRIL 29, 2020, by Max Planck Society
https://medicalxpress.com/news/2020-04-heart-affects-perception.html

Left: The detection rate is reduced during systole (red) compared to diastole (blue). Right: In systole a specific component of brain activity, which is associated with consciousness, the so called P300-component is suppressed. 

Credit: © MPI CBS/ PNAS

The heart and brain communicate constantly. For example, when encountering a dangerous situation, signals from the brain ensure that the heart beats faster. When relaxing, the heart slows down. Interestingly, the heartbeat also affects the brain, but the underlying mechanisms are unclear. Researchers at the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig and Berlin School of Mind and Brain have now identified two mechanisms underpinning how the heart influences perception and the brain, and how these mechanisms differ between individuals.

The first mechanism establishes a relationship between the phase of the heartbeat and conscious experience. In a regular rhythm, the heart contracts in the so-called systolic phase and pumps blood into the body. In a second phase, the diastolic phase, the blood flows back and the heart fills up again. In a previous publication from the MPI CBS, researchers reported that perception of external stimuli changes with the heartbeat. In systole, it is more difficult to detect a weak electric stimulus in the finger compared to diastole.

Now, in a new study, Esra Al and colleagues have found the reason for this change in perception: Brain activity is changing over the heart cycle. In systole, a specific component of brain activity associated with consciousness, the so-called P300 component is suppressed. In other words, it seems that in systole, the brain makes sure that certain information is kept out of conscious experience. The brain seems to take into account the pulse in systole and predicts that pulse-associated bodily changes are "not real," but rather due to the pulse. Normally, this suppresses conscious awareness of the pulse. However, weak stimuli that coincide with systole we might be missed although they are real.

During their investigations on heart-brain interactions, Al and colleagues also revealed a second effect of heartbeat on perception: If a person's brain shows a higher response to the heartbeat, the processing of the stimulus in the brain is attenuated—the person detects the stimulus less. "This seems to be a result of directing our attention between external environmental signals and internal bodily signals," explains study author Al. In other words, a large heartbeat-evoked potential seems to reflect a "state of mind" in which we are more focused on the functioning of our inner organs such as the blood circulation, but less aware of stimuli from the outside world.

The results not only have implications for our understanding of heart-brain interactions in healthy persons, but also in patients. Senior author Arno Villringer explains, "The new results might help to explain why patients after stroke often suffer from cardiac problems and why patients with cardiac disease often have impaired cognitive function."

The researchers investigated these relationships by sending weak electrical stimuli to electrodes clamped onto the study participants fingers. In parallel, they recorded each participants' brain processes using an EEG and their cardiac activity using an EKG.

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Hidden Geometric Pattern Reveals Deeper Complexity of Göbekli Tepe

27 APRIL, 2020 -  ASHLEY COWIE
https://www.ancient-origins.net/news-history-archaeology/gobekli-tepe-geometry-0013627

Close-up of the Göbekli Tepe site in central Turkey. Source: Brian Weed / Adobe stock

Does a “hidden-pattern” at Göbekli Tepe in central Turkey suggest 12,000-year-old hunter-gatherers knew rudimentary geometric principals, indicating a more complex society than previously assumed by archaeologists, or not?

The first phase of construction at the famous Göbekli Tepe, or “potbellied hill” in Turkish, has been dated to between 12,000 and 11,000 years ago, and this prehistoric stone circle, located on a barren hilltop in southeastern Turkey, has challenged archaeologists’ ideas about prehistoric cultures since its discovery in the 1990s. Many leading archaeologists have been perplexed as to how the assumed to be primitive hunter-gatherers could design and assemble such a massive monumental stone structure before the emergence of the social order that came with agriculture?

Now, Israeli archaeologists, Gil Haklay and his PhD advisor Avi Gopher, of Tel Aviv University , have published a new study in the Cambridge Archaeological Journal providing a set of observations suggesting this prehistoric building project was “much more complex than previously thought”, and that it required planning and resources to a degree thought of as being impossible for those times.

Three Contemporaneous Stone Circles, Perhaps?
At this world-renowned archaeological site several concentric stone circles feature massive T-shaped pillars that reach almost 6 meters (20 ft) in height with animals and anthropological motifs carved in relief. But this new study focuses on the arrangement and positioning of the three oldest circular stone enclosures at Göbekli Tepe and the researchers claim that underlying the entire architectural plan of these three structures is “a hidden geometric pattern,” which they describe as being “specifically an equilateral triangle.”

Close-up of a stone pillar at Göbekli Tepe with an intricate relief carving. (Zhengan / CC BY-SA 4.0 )

Until these new observations, most archaeologists had assumed that the circles at Göbekli Tepe had been built gradually, over a long time period, possibly by different cultural groups, and that older circles were covered over with the new. Never was it considered that all three enclosures might have been constructed “as a single unit at the same time,” said the researchers. Researcher Haklay told Haaretz that while the initial discovery of the site was a big surprise for the archaeological world, his new research confirms its construction was even “more complex than we thought.”
New “Single Project” Theory Challenges the Mainstream

The new study focuses on enclosures B, C, and D, which have been dated to slightly older than enclosure A, and Haklay, who was previously an architect, applied a method of interpretation known as “architectural formal analysis” to retrace the ancient builders planning principles and methodologies.

Using an algorithm, Haklay identified the center points of the three irregular stone circles, which fell roughly mid-way between the pair of central pillars in each enclosure. The eureka moment came when the three central points were found to form a nearly perfect equilateral triangle, so accurate in measure, that the researchers say the “vertices are about 25 centimeters (10 inches) away from forming a perfect triangle with sides measuring 19.25 meters (63 ft) each”.

Story continue's at:  https://www.ancient-origins.net/news-history-archaeology/gobekli-tepe-geometry-0013627

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Bronze Age swords bear the marks of skilled fighters

APRIL 27, 2020, by Newcastle University
https://phys.org/news/2020-04-bronze-age-swords-skilled-fighters.html

An example of the damage caused by one of the replica swords. Credit: Bronze Age Combat Team/Hotspur School of Defence

Warriors during the Bronze Age used their weapons in skillful ways that would have required lots of training in specific techniques, researchers say.

A team led by Newcastle University examined thousands of marks on Bronze Age swords and staged experimental fights using replica weapons to better understand how they might have been used in the Bronze Age and the combat techniques that were needed.

Bronze—cast by mixing copper and tin—is softer than steel, meaning that it can be easily damaged. Until now, much speculation has focused on the possibility that because they are easy to damage, the ancient weapons were ceremonial rather than intended for battle.

However, the research findings, published in the Journal of Archaeological Method and Theory, indicate that not only were they used in active combat, but would have required fighters to use lots of skill and very particular techniques to minimize the amount of damage.

The work came out of the Bronze Age Combat Project (BACP), led by Dr. Andrea Dolfini at Newcastle University, and involving colleagues from Leicester and Durham universities, the British Museum and Great North Museum: Hancock.

Dr. Dolfini said: "The Bronze Age was the first time people used metal specifically to create weapons they could use against other people.

"People understood that these weapons could be very easily marked so sought to use them in ways that would limit the amount of damage received. It is likely that these specialized techniques would have to be learned from someone with more experience, and would have required a certain amount of training to be mastered."

The research involved staging experimental fights using replica weapons. Credit: Bronze Age Combat Team/Hotspur School of Defence

The research team worked with members of Newcastle-based Hotspur School of Defence, a club dedicated to medieval European combat, to stage realistic sword fighting sequences, using specially commissioned replica weapons. Wearing protective clothing, and using moves found in a combat manual from the Middle Ages, the trained volunteers tried a wide variety of sword, shield and spear strikes delivered to different body parts as researchers recorded the types of damage inflicted by different blows.

This revealed more about how swords and shields could have been used, and the type of damage that different strikes made to the weapons.

Armed with this knowledge, the researchers then used sophisticated use-wear analysis techniques to examine 2,500 wear marks on 110 ancient swords from Great Britain and Italy, comparing the damage marks on both the ancient weapons and the replicas.

This detailed two-part analysis allowed the research team to assign certain wear marks to specific sword moves and combinations. This indicated that fighters used their weapons to control and dominate the blade of their opponent, suggesting that much combat took place at close quarters.

Distinct styles

The sword combat and use-wear analysis elements of the research were led by Raphael Hermann while working towards his Ph.D. at Newcastle University. Talking to Science magazine, Dr. Hermann, who is now at the University of Göttingen, said: "In order to fight the way the marks show, there has to be a lot of training involved, and because the marks are so consistent from sword to sword, they suggest that different warriors weren't swinging at random, but were using well-practiced techniques. We also saw that wear patterns were linked to geography and time, suggesting distinct fighting styles developed over centuries."

It is the first time that anyone has used such an approach to get a better understanding of ancient combat and the research team anticipate that their work provides a new model for conducting research into ancient warfare.

Dr. Dolfini added: "You can't just give two people replicas of ancient weapons, tell them to fight and then say 'we know how they were used." What we did with the Bronze Age Combat Project is creating a meaningful blueprint for carrying out future experimental research into prehistoric combat, building a much greater understanding of how ancient weapons were used and the role of warriors in Bronze Age societies."

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Discovery: Scientists find for the first time how the eyes drain cellular waste and debris

FEATURE  APRIL 27, 2020, by Delthia Ricks , Medical Xpress
https://medicalxpress.com/news/2020-04-discovery-scientists-eyes-cellular-debris.html

Credit: CC0 Public Domain

Just as the brain is a privileged organ, so too are the eyes. Often poetically called the windows to the soul, a unique set of studies has begun to regard the eyes in another way. Like the brain, the eyes lack the classic lymphatic vessels responsible for the circulation of fluids and removal of waste products, as is common in peripheral organs. In recent years, it was discovered that the brain possesses a unique "glymphatic" system, a privileged brain-only method of draining and disposing of molecular wastes. This transport system, when healthy, involves shuttling neurotoxic proteins such as amyloid-β out of the brain. On the flip side, an unhealthy system allows amyloid to accumulate into dangerous, mind-robbing plaques.

Now, an international team led by Dr. Maiken Nedergaard, a neuroscientist at the University of Copenhagen in Denmark, and Xiaowei Wang of both the University of Copenhagen and the University of Rochester in New York, have found evidence of a glymphatic system in the mammalian eye. Nedergaard is the discoverer of the brain's waste disposal system and the scientist who coined the term "glymphatic."

The new findings explain how a glymphatic system maintains eye health and underscores that impairment—clogging—of this vital waste pathway can lead to glaucoma, a major worldwide cause of blindness. Nedergaard has defined "glymphatic" as an amalgam of the words glial and lymphatic. Glial cells are the primary cellular components that support neurons—nerve cells. The glymphatic pathway substitutes for a lymphatic system, which exists in neither the brain nor the eye.

Writing in Science Translational Medicine the researchers reported that the glymphatic system in the eye closely resembles the function of the glymphatic pathway in the brain. Moreover, they concluded, the drainage system is responsible for eliminating metabolic, cellular and other debris from the eyes. The discovery was made by a far-flung research team, which, beyond Denmark and New York, included members at the University of California at Berkeley, Haukeland University Hospital in Norway, Ludwig Maximilians University in Germany, and several other leading research centers.

"Similar to the brain inside the cranial vault, the internal structures of the eye are contained within a confined space, necessitating tight control of fluid homeostasis," Nedergaard wrote. "Yet, both the eye and the brain are largely devoid of traditional lymphatic vessels, which are critical for the clearance of fluid and solutes from peripheral tissues."

To find out if a glymphatic system actually exists in the eyes, scientists turned to laboratory mice as their mammals of choice. By injecting fluorescently labeled tracers—including tagged human amyloid-β – into the clear, gel-like vitreous fluid inside the eyes of mice, the researchers were able to track the toxic amyloid proteins as they moved out of the eyeballs through discrete channels in the optic nerve. The debris ultimately was shuttled to the lymphatic vessels in the neck.

Intriguingly, the team found the lymphatic vessels are connected to the same pathways that dispose wastes from the brain. The discovery is a scientific first and opens a new window into understanding how the eyes clear metabolic and cellular debris. The findings also shed new light on how the eyes and brain share critical pathways.

Even though the finding is new, the waste clearance system in the brain was first defined by Nedergaard in 2012. The pathway involves a labyrinth of intricate perivascular tunnels that are formed by glial cells, which underlie the efficient elimination of soluble metabolites from the central nervous system. In addition to waste disposal, Nedergaard and colleagues also have found that the pathways support the distribution of critical nutrients and compounds throughout the brain, substances that include glucose, amino acids, growth factors and lipids.

She and her team uncovered a largely nocturnal system regarding the brain's glymphatic system. They reported in earlier studies that glymphatic processes function only during the sleep cycle and are switched off during wakefulness. In a joint study five years ago with the University of Rochester, Stony Brook University and NYU Langone Medical Center, all in New York, Nedergaard found that sleeping on one's side best facilitates the function of the brain's glymphatic system and the clearance of debris. She noted at the time that the lateral sleeping position—sleeping on one's left or right side—is common among mammals. Humans, hibernating bears, domesticated dogs and cats—numerous members of the animal kingdom—spend part or all of their time during the sleep cycle on their sides.

"It is interesting that the lateral sleep position is the most popular in humans and most animals, even in the wild," Nedergaard said at the time.

However, in her latest research, Nedergaard and her team found that it wasn't sleep and darkness that drove the transport of wastes from the eyes. Instead, exposure to light activated the flow of cellular and metabolic debris out the eyes of test animals.

Additionally, the team wanted to learn how the system was associated with eye disease when waste transport didn't function well. To better understand the link between the flow of wastes and glaucoma, the researchers examined two different glaucoma mouse models. Glaucoma causes blindness by damaging the optic nerve.

Even though the researchers predicted that higher intraocular pressure would shuttle amyloid more efficiently out of the eyes, mice with glaucoma instead retained much of the toxic protein inside their eyes. Nedergaard and her team say their findings suggest a link between glaucoma and the malfunctioning of the eyes' glymphatic drainage pathways.

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They remember: Communities of microbes found to have working memory

APRIL 27, 2020, by University of California - San Diego
https://phys.org/news/2020-04-microbes-memory.html

Memory imprints: Researchers used light exposure to impress a complex pattern (UC San Diego's former Geisel Library logo, spread across an area slightly smaller than the thickness of a human hair) onto a biofilm community--made up of hundreds of individual bacteria--that remembered the initial light stimulus, similar to how neurons form memory. Credit: Suel Lab, UC San Diego

Biologists studying collectives of bacteria, or "biofilms," have discovered that these so-called simple organisms feature a robust capacity for memory.

Working in the laboratory of University of California San Diego Professor Gürol Süel, Chih-Yu Yang, Maja Bialecka-Fornal and their colleagues found that bacterial cells stimulated with light remembered the exposure hours after the initial stimulus. The researchers were able to manipulate the process so that memory patterns emerged.

The discovery reveals surprising parallels between low-level single-cell organisms and sophisticated neurons that process memory in the human brain.

"Even just a few years ago people didn't think bacterial cells and neurons were anything alike because they are such different cells," said Süel. "This finding in bacteria provides clues and a chance to understand some key features of the brain in a simpler system. If we understand how something as sophisticated as a neuron came to be—its ancient roots—we have a better chance of understanding how and why it works a certain way."

The findings, described April 27 in the journal Cell Systems, also provide a starting path for scientists to one day design basic computing systems with living organisms such as bacteria.

https://youtu.be/RnHboG1ERlw

Following recent discoveries by the Süel lab that bacteria use ion channels to communicate with each other, new research suggested that bacteria might also have the ability to store information about their past states. In the new study, the researchers were able to encode complex memory patterns (video here) in bacterial biofilms with light-induced changes in the cell membrane potential of Bacillus subtilis bacteria. The optical imprints, they found, lasted for hours after the initial stimulus, leading to a direct, controllable single-cell resolution depiction of memory.

"When we perturbed these bacteria with light they remembered and responded differently from that point on," said Süel. "So for the first time we can directly visualize which cells have the memory. That's something we can't visualize in the human brain."

The ability to encode memory in bacterial communities, the researchers say, could enable future biological computation through the imprinting of complex spatial memory patterns in biofilms.

"Bacteria are the dominant form of life on this planet," said Süel. "Being able to write memory into a bacterial system and do it in a complex way is one of the first requirements for being able to do computations using bacterial communities."

Further, as the researchers note in the study: "It may thus be possible to imprint synthetic circuits in bacterial biofilms, by activating different kinds of computations in separate areas of the biofilm... Overall, our work is likely to inspire new membrane-potential-based approaches in synthetic biology and provide a bacterial paradigm for memory-capable biological systems."

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Sustainable light achieved in living plants

APRIL 27, 2020, by MRC London Institute of Medical Sciences
https://phys.org/news/2020-04-sustainable.html

Glowing flowers. Credit: Planta

The movie Avatar evoked an imaginary world of lush bioluminescent jungles. Now the popular fascination for sustainably glowing foliage is being realized through advances in designer genetics. This week in Nature Biotechnology, scientists have announced the feasibility of creating plants that produce their own visible luminescence.

The scientists revealed that bioluminescence found in some mushrooms is metabolically similar to the natural processes common among plants. By inserting DNA obtained from the mushroom, the scientists were able to create plants that glow much brighter than previously possible.

This biological light can be used by scientists for observing the inner workings of plants. In contrast to other commonly used forms of bioluminescence, such as from fireflies, unique chemical reagents are not necessary for sustaining mushroom bioluminescence. Plants containing the mushroom DNA glow continuously throughout their lifecycle, from seedling to maturity.
The new discovery can also be used for practical and aesthetic purposes, most notably for creating glowing flowers and other ornamental plants. And while replacing street lights with glowing trees may prove fantastical, the plants produce a pleasant green aura that emanates from their living energy.

The report in Nature Biotechnology was authored by 27 scientists, led by Drs. Karen Sarkisyan and Ilia Yampolsky. The research was carried out principally through a collaboration between Planta, a biotech startup in Moscow, the Institute of Bioorganic Chemistry of the Russian Academy of Sciences, MRC London Institute of Medical Sciences, and the Institute of Science and Technology Austria. Financial support was provided by Planta, the Skolkovo Foundation, and the Russian Science Foundation.

Glowing young plants. Credit: Planta

According to the authors, the plants can produce over a billion photons per minute. Dr. Keith Wood, CEO of Light Bio, states that "thirty years ago, I helped to create the first luminescent plant using a gene from fireflies. These new plants can produce a much brighter and more steady glow, which is fully embodied within their genetic code." Light Bio is a new company that plans to commercialize this novel technology in ornamental house plants in partnership with Planta.

Designing new biological features is more complex than merely moving genetic parts from one organism to another, however. Like gears in a watch, the newly added parts must metabolically integrate within the host. For most organisms, the parts needed for bioluminescence are not all known. Until recently, a complete part list was available only for bacterial bioluminescence. But past attempts to create glowing plants from these parts have not gone well, largely because bacterial parts typically do not work properly in more complex organisms.

Little more than a year ago, scientists uncovered the parts that sustain bioluminescence in mushrooms. For the first time, the living light of an advanced multicellular organism was fully defined. In the present report, the authors disclose that mushroom bioluminescence works particularly well in plants. This allowed them to make glowing plants that are at least ten-fold brighter. Using ordinary cameras and smartphones, green illumination was recorded coming from leaves, stems, roots, and flowers. Moreover, the sustained light production was achieved without harming the health of the plants.

Although mushrooms are not closely related to plants, their light emission centers on an organic molecule that is also needed in plants for making cell walls. This molecule, called caffeic acid, produces light through a metabolic cycle involving four enzymes. Two enzymes convert the caffeic acid into a luminescent precursor, which is then oxidized by a third enzyme to produce a photon. The last enzyme converts the oxidized molecule back to caffeic acid to start the cycle again.

Credit: Planta (screen cap of short vid)

In plants, caffeic acid is a building block of lignin, which helps provide mechanical strength to the cell walls. It is thus part of the lignocellulose biomass of plants, which is the most abundant renewable resource on Earth. As a key component of plant metabolism, caffeic acid is also integral to many other essential compounds involved in colors, fragrances, antioxidants, and so forth. Despite their similar sounding names, caffeic acid is not related to caffeine.

By connecting light production to this pivotal molecule, the glow emitted by the plants provides an internal metabolic indicator. It can reveal the physiological status of the plants and their responses to the environment. For instance, the glow increases dramatically when a ripe banana skin is placed nearby (which emits ethylene). Younger parts of the plants tend to glow most brightly and the flowers are particularly luminous. Flickering patterns or waves of light are often visible, revealing active behaviors within the plants that normally would be hidden.

In this published research, the authors relied on tobacco plants because of their simple genetics and rapid growth. But the benefits of mushroom bioluminescence are broadly fitting to plants. Research at Planta, and by Arjun Khakhar and colleagues, have demonstrated feasibility for other glowing plants, including periwinkle, petunia, and rose. Even brighter plants can be expected with further development. New features may be possible, such as changing brightness or color in response to people and surroundings. Through this living aura, we may even gain a new awareness of our plants that emulate the inspiring allure of Avatar.

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Soil in wounds can help stem deadly bleeding

By Kerry Blackadar | April 27, 2020
https://www.med.ubc.ca/news/soil-in-wounds-can-help-stem-deadly-bleeding/

New UBC research shows for the first time that soil silicates—the most abundant material on the Earth’s crust—play a key role in blood clotting.

“Soil is not simply our matrix for growing food and for building materials. Here we discovered that soil can actually help control bleeding after injury by triggering clotting,” says the study’s senior author Dr. Christian Kastrup, associate professor in the faculty of medicine’s department of biochemistry and molecular biology and a scientist in UBC’s Michael Smith Laboratories and Centre for Blood Research.

The study, published today in Blood Advances, found that the presence of soil in wounds helps activate a blood protein, known as coagulation Factor XII. Once activated, the protein kicks off a rapid chain reaction that helps leads to the formation of a plug, sealing the wound and limiting blood loss.

While the researchers caution that there is a high risk of infection from unsterilized dirt, they say their findings may have implications for the future development of novel strategies using sterilized dirt to help manage bleeding and potentially understand infection after trauma.

“Excessive bleeding is responsible for up to 40 per cent of mortality in trauma patients. In extreme cases and in remote areas without access to healthcare and wound sealing products, like sponges and sealants, sterilized soil could potentially be used to stem deadly bleeding following injuries,” says Dr. Kastrup.

“Soil is not simply our matrix for growing food and for building materials. Here we discovered that soil can actually help control bleeding after injury by triggering clotting.”

Dr. Christian Kastrup

The study also uncovered that the mechanism by which soil silicates activate Factor XII and promote faster clotting is unique to terrestrial mammals, or those that live predominantly or entirely on land.

“This finding demonstrates how terrestrial mammals, ranging from mice to humans, evolved to naturally use silicates as a specific signal to Factor XII to trigger blood clotting,” says Lih Jiin Juang, the study’s first author and UBC PhD student in the department of biochemistry and molecular biology. “These results will have a profound impact on the way we view our relationship with our environment.”

The scientists’ next plan includes testing if the response of blood to silicates helps prevent infection from microbes in soil. They will also look to test if silicates from the moon’s surface are able to active Factor XII and stop bleeding.

“If moon silicates activate Factor XII, this discovery could prove useful in preventing death among people visiting or colonizing the moon, and it would provide further insight to identifying materials that may halt bleeding in very remote environments with limited resources and medical supplies,” says Dr. Kastrup.

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Surreal Footage Shows 'Glowing' Dolphins Surf Through Bioluminescent Algae

CARLY CASSELLA           27 APRIL 2020
https://www.sciencealert.com/watch-these-dolphins-turn-into-glowing-torpedos-scaring-algae-so-bad-they-poop-light

(Patrick Coyne/Newport Coastal Adventures)

The first time Californian photographer Patrick Coyne saw a pod of dolphins dancing in bioluminescent waters, it was on Netflix. The second time, it was in person - camera in hand - on what he now describes as one of the most magical nights of his life.

After searching for hours in the pitch black off the coast of California's Newport beach, Coyne recently captured a rare glimpse of these glowing torpedos on a local nightly tour.

"We were out for a few hours and on our final stretch back we finally had 2 Dolphins [sic] pop up to start the incredible glowing show," writes Coyne on his Instagram.

"A few minutes later and we were greeted by a few more which was insane. I'm honestly still processing this all… "

https://youtu.be/bJcTWr8-mFo

The video Coyne has made from the trip is truly breathtaking, but he says it was challenging to film. Bioluminescence is hard to spot and ephemeral by nature, so getting footage requires the perfect conditions and a bit of luck.

In coastal regions, bioluminescence is caused by microscopic organisms called dinoflagellates. These tiny marine "fire plants" are members of the plankton family and they are quite sensitive to movement of any sort.

So much so, that when they are poked or prodded by a predator, each cell emits a flash of light lasting up to 100 milliseconds, almost like a burglar alarm. If there's a whole bunch of algae concentrated together, as Coyne's video shows, a flip of the fin can lead to quite the show.

Retweeting the video, ecologist Rebecca Helm from the University of North Carolina Asheville used a funnier metaphor to describe the phenomenon - although it's not entirely correct. "Ahhh beautiful: dolphins scaring algae so bad they poop light."

She later corrected herself because dinoflagellates don't actually eject the chemicals - it's more like "luminous little panic attacks", she explained.

Dinoflagellates produce two chemicals that create a glowing reaction when they're startled. These are known as the enzyme luciferase and the compound luciferin, and together they cause the dinoflagellate to glow at night when they are mechanically disturbed.

In fact, this very phenomenon is where we get the name "night light", and it's known to occur inside and outside several different marine species, often as a way of scaring off predators.

Turns out, not so effective on humans - to us it just looks stunning.

another vid added by CiC

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Ancient Cave Found in Egypt with Unique Predynastic Rock Carvings

26 APRIL, 2020 -  ED WHELAN
https://www.ancient-origins.net/news-history-archaeology/egyptian-rock-art-0013625

The cave where the rock art was discovered. Inset: One of the sections of rock carvings. Photos courtesy of Ministry of Antiquities

In Egypt, archaeologists from the Ministry of Tourism and Antiquities have found a mysterious and diverse collection of rock art. They were located deep in a cave in the Sinai and are not like anything else found yet. These enigmatic images could provide invaluable insights into the prehistory of Egypt.

An archaeological mission from the Ministry of Tourism and Antiquities were investigating a cave at Wadi al-Zulma, in Northern Sinai. It was during their exploration of the site that they found the mysterious rock carvings. The site is located in a valley in a mountainous area and is about 76 miles (90km) south of the city of al-Qantara Sharq, and some 38 miles (60 km) east of the Suez Canal.

The ancient cave was found in a mountainous area in Northern Sinai. 

Photo courtesy Ministry of Antiquities Unique Rock Carvings

The cave is located high on a hillside, overlooking the valley and it is made of limestone. It is quite difficult to access. The height of the cave is 60 feet (20 m) and 45 feet deep (15 m). In the cavern, the team of experts were shocked to find a large number of rock carvings that are of a type not seen before. Ayman Ashmawy, a senior official with the Egyptian Ministry of Antiquities told Egypt Independent that ‘this cave is the first of its kind to be found in the area’.

Sinai has great many rock carvings and an important collection of them was found at al-Zaranji cave, earlier this year, the in the south of the peninsula. Here a great many images were found that predated the Pharaohs and that possible date to 10,000 years ago. They were stylistically similar to other examples of cave art in the southern valleys of Sinai.

Story continues with more pics at:  https://www.ancient-origins.net/news-history-archaeology/egyptian-rock-art-0013625

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Further evidence for bow hunting and its implications more than 60 000 years ago: Results of a use-trace analysis of the bone point from Klasies River Main site, South Africa

Justin Bradfield a, Marlize Lombard a, Jerome Reynard b, Sarah Wurz, bc.

a.     Palaeo-Research Institute, University of Johannesburg, P.O. Box 524, Auckland Park, 2006, Johannesburg, South Africa
b.     School of Geography, Archaeology and Environmental Science, University of the Witwatersrand, South Africa
c.     SFF Centre for Early Sapiens Behaviour (SapiensCE), University of Bergen, Bergen, Norway

Received 18 October 2019, Revised 2 March 2020, Accepted 30 March 2020, Available online 20 April 2020.

added by CiC , not from article.

Highlights

•        The bone point (SAM 42160) from >60 ka deposits at Klasies River Main Site, South Africa, is reassessed.

•         We clarify the stratigraphic integrity of SAM 42160 and confirm its Middle Stone Age provenience.

•        Evidence indicate the point was hafted, experienced high-velocity, longitudinal impact, and was partially coated in an adhesive substance.

•        SAM 42160 likely functioned as a hafted arrowhead.

•       E explore the cognitive implications for bow hunting in the Middle Stone Age.


Abstract

The bone point (SAM 42160) from >60 ka deposits at Klasies River Main Site, South Africa, is reassessed.
We clarify the stratigraphic integrity of SAM 42160 and confirm its Middle Stone Age provenience. We find evidence that indicates the point was hafted and partially coated in an adhesive substance.
Internal fractures are consistent with stresses occasioned by high-velocity, longitudinal impact.
SAM 42160, like its roughly contemporaneous counterpart, farther north at Sibudu Cave, likely functioned as a hafted arrowhead.

We highlight a growing body of evidence for bow hunting at this early period and explore bow-and-arrow technology might imply about the cognition of people in the Middle Stone Age who were able to conceive, construct and use it.

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The Fall of the Giants and Their Fate According to Ancient Texts

26 APRIL, 2020 - ANCIENT-ORIGINS, By Adam Oliver Stokes
https://www.ancient-origins.net/myths-legends-americas/giants-0013621

Is the answer of the downfall of the giants found in ancient texts? Source: grandfailure / Adobe Stock.

Giants were here. In using the term giants, I am referring to persons at least 7 feet (2.1m) and up to 13 feet (4m) in height. Given that pre-modern man was significantly shorter on the average than we are today (many athletes in modern times are 6’5” or taller (2 meters)) these giants would have certainly seemed of extraordinary stature.

That an ancient race or races of giants once existed throughout the world, from China to North America, is a matter attested to not only in the written records of various civilizations but in the archaeological record as well. As Jason Jarrell and Sarah Farmer note, the vast number of gigantic humanoid skeletal remains excavated in the North American region alone makes it statistically highly unlikely for us to interpret all of them as genetic anomalies as mainstream scholars often do.

Giants were here. Yet, this observation leads us immediately to another problematic question: If giants-as a race or races-once existed in antiquity, why do they not exist now? What happened to them? What factors led to their extinction?

The archaeological record largely, though not entirely, fails us in answering these questions. This is particularly evident in the work done on giant civilization(s) in North America. North American archaeologists and anthropologist have done amazing work addressing the unique cultural features of the Hopewell and Adena, pre-Columbian peoples who were either themselves giants or direct descendants of a previous race of giants. At the same time, North American archaeology is at pains to explain the sudden disappearance of both of these civilizations sometime around 500 AD.

In this article, I will propose an alternative anthropological method for determining the fate of the ancient giants. Rather than attempting to interpret the sparse and inconclusive archaeological evidence, I suggest that scholars turn to ancient texts and the mythological/religious traditions they contain. As Erik Von Daniken notes, ancient literature, while highly mythological, often retains fact at its core.

Colossal statue of the giant Appenino. (Picryl / Public Domain )

Furthermore, as Von Daniken also points out, many of the narratives contained in ancient texts are themselves far more literal than modern 21 st century academics give them credit for. When this material is taken into consideration, it suggests that many of the ancient giant civilization(s) were violent and oppressive in their culture and that eventually they were destroyed through their own violent tendencies and actions.

The Description of Giants in Ancient Literature

As Xaviant Haze notes in his recent work Ancient Giants , tales and stories of giants are a universal phenomenon found in nearly every human culture throughout recorded human history. When these various accounts are examined, one common theme emerges, namely that the giants and the civilizations they created were defined by violence and bloodshed. While a comprehensive examination of giants in ancient oral and written traditions is well beyond the scope of this article, it is possible to narrow our focus here to the treatment of giants within a particular culture and their body of literature.

As someone with a background in biblical studies, the ancient Israelites immediately came to mind as the best candidates for such an examination. In contrast to many other ancient Near Eastern societies, the history of ancient Israel is very well documented in both biblical (i.e. the Old Testament/Hebrew Bible) and extra-biblical sources.

The ‘Book of Giants’ tells the story of pre-diluvian origins of evil and the fate of the Watchers and their giant offspring.

(Chauvelin2000 / Public Domain )

One of the earliest references to giants in Israel comes from the Yahwist account of the great deluge found in Genesis chapter 6. (The Yahwist being one of the four authors or sources for the material in the first five books of the Old Testament commonly referred to as the Torah or Pentateuch. The four source theory was popularized in the late 19th century in the work of the famous German biblical scholar Julius Wellhausen.) Here they are linked to the “ sons of God ” (Hebrew: bene ‘elohim ) who forcefully take the “daughters of men” ( banot ‘anashim ) as wives.

The Latin translation of the Genesis 6 passage reads:

Gigantes autem erant super terram in diebus illis: postquam enim ingress sunt filii Dei ad filias hominum illaeque genuerunt isti sunt potentes a saeculo viri famosi

But giants were over the earth in those days. For after the sons of God entered into the daughters of men and these (women) gave birth. These are the powerful ones from long ago, the famous men. (Genesis 6:4)

(All translations of Latin or Hebrew texts are mine unless noted as otherwise.)

The Old Testament shares stories about giants taking human women. (JarektUploadBot / Public Domain )

This article continued at:  https://www.ancient-origins.net/myths-legends-americas/giants-0013621

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