It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, July 09, 2021
How robots and brain-computer interfaces could transform stroke patients' recovery
IMAGE: STROKE REHABILITATION ROBOT BASED ON BRAIN-COMPUTER INTERFACE TECHNOLOGY AND BRAIN-INSPIRED INTELLIGENT ROBOT TECHNOLOGY. view more
CREDIT: BRAINCO, LTD.
Strokes, which occur when the blood supply to part of our brain is interrupted or reduced, are the leading cause of death and disability in the adult population. Among the patients who survive, 75% will experience difficulties carrying out daily activities independently and need long-term functional exercises and rehabilitation. But the outcomes using traditional rehabilitation equipment are poor. In addition, the motivation of patients to train is often low.
The Department of Neurology in Tongji Hospital, which is affiliated to Tongji Medical College at the Huazhong University of Science and Technology, is recognised in China for the quality of its scientific research and clinical strength. Similarly, Zhejiang BrainCo, Ltd., incubated by the Harvard Innovation Lab, is a market leader in terms of brain-computer interfaces; considered by many the next generation of artificial intelligence technology.
In the NCyborg Project, the two organisations will draw on their expertise in brain-computer interface technology and brain-inspired intelligent robot technology to establish a stroke rehabilitation process driven by patient initiative. In a paper published in the KeAi journal Brain Hemorrhages, they outline the project's three focus areas:
1.An algorithm for analysing the movement intention of stroke patients based on brain-computer interface technology. 2. A motion control strategy for a rehabilitation robot based on brain-inspired motion perception. 3.The mechanism of stroke rehabilitation using brain-inspired intelligent robots.
They will begin by training the robot to support rehabilitation of the hand - a body part often left with limited movement following a stroke. The team aims to achieve recognition of no less than eight hand movement intentions with an accuracy rate of ?90% and a response time of ?300 ms.
Co-corresponding author, Jonh H. Zhang, explains: "The project's goal is to develop an easy-to-use, reliable and affordable stroke rehabilitation robot that will improve the rehabilitation effect for stroke survivors, speed up the rehabilitation process, and reduce the costs involved."
His co-corresponding author, Bicheng Han, adds: "Our hope is that, within five years, millions of stroke patients will be using this product and see their lives improve."
According to co-corresponding author Zhouping Tang, the 'N' in the NCyborg Project name stands for 'neural', while in fictional stories 'cyborg' is often "an icon that is enhanced mentally and/or physically over and above the 'norm' with technology. In the real word, we believe that NCyborg Project will set up a brand-new stroke rehabilitation pattern which could qualitatively improve the treatment effect for stroke survivors."
The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 100 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).
The giant panda's mystery revealed
The evolution of the temporomandibular joint and premolar teeth enabled adaptation to bamboo diet
IMAGE: THE GIANT PANDA'S STOMATOGNATHIC SYSTEM HAS ADAPTED TO ALLOW THE USE OF BAMBOO AS NUTRITION. view more
CREDIT: PEKKA VALLITTU
Although the giant panda is in practice a herbivore, its masticatory system functions differently from the other herbivores. Through the processes of natural selection, the giant panda's dietary preference has strongly impacted the evolution of its teeth and jaws. Researchers from the Institute of Dentistry at the University of Turku and the Biodiversity unit of the University of Turku together with researchers from the China Conservation and Research Center for Giant Panda (CCRCGP) have been the first in the world to solve the mystery of how the giant panda's special stomatognathic system functions.
The bamboo diet of the giant panda (Ailuropoda melanoleuca) has long been a mystery for researchers. The panda is in practice a herbivore, and its diet only consists of few dozen species of bamboo. Related to the consumption of bamboo, the giant panda has a special characteristic of peeling the green outer skin of all bamboo shoots, rich in abrasive and toxic compounds, by the highly adapted premolars.
Herbivores have usually evolved to have ridged molars that help them grind the plant material and jaws capable of moving sideways which is essential for grinding their food. Although the teeth of giant pandas have been studied extensively, until now, researchers have not paid attention to why the large canines of their upper jaw do not prevent the sideways movement of the lower jaw typical for herbivores - and also humans. The key to this has been the evolution of the temporomandibular joint and the premolar teeth.
Evolution of the Temporomandibular Joint Allows Sideways Movement
Using modern 3D scanning methods, the research group studied the movement of the giant panda's jaw and the structure of its teeth and found the answer to the question that had puzzled researchers for over a century: how are giant pandas able to use bamboo as their diet. The solution was that the panda's temporomandibular joint has evolved to differ from that of e.g. brown bear and polar bear. In addition to the open-closed movement reminding that of a hinge, the joint also allows the jaw to be moved sideways, which is required to peel the bamboo. Interestingly, this movement isn't prevented by the large canines the male pandas need to fight.
- The necessity to ensure adequate nutrition has helped evolve the temporomandibular joint and the shape of the teeth to allow efficient peeling of the bamboo without without exposing the premolars to the attritive or other damaging effect of bamboo diet, explains Professor Pekka Vallittu from the Institute of Dentistry.
CAPTION
The panda's temporomandibular joint and premolars enable them to peel the bamboo.
CREDIT
Pekka Vallittu
The evolution of the giant panda's masticatory system, as demonstrated in the study, allowed them to be the only large mammals to access an endless source of nutrition in the form of bamboo in the early Pleistocene.
- The premolars giant pandas use for peeling bamboo are unique among the family of bears and allow the removal of the poisonous green skin of the bamboo which also includes mineral crystals which would wear their teeth, says Professor Juha Varrela from the Institute of Dentistry.
The study of how the giant panda's masticatory system functions also helps to understand human's occlusion and its characteristics better.
- Whether giant pandas grind their teeth still remains to be seen, ruminates Vallittu.
- This newly published study is of great scientific significance because it solves the long-prevailing mystery of the ecological interrelationship between the pandas and the bamboo plants, says Professor Jukka Salo from the Biodiversity Unit of the University of Turku.
CAPTION
Modern 3D scanning methods developed by Planmeca Corp. allow the researchers to closely investigate the movement of the panda's jaw and the structure of its teeth.
CREDIT
Pekka Vallittu
Salo has been an active participant in the panda project of the Finnish Ähtäri Zoo and the study of the panda habitat in the Qionglai Mountains in the Sichuan province of China. Professor of Environmental Sciences and Biodiversity Pekka Niemelä from the University of Turku has also studied pandas in the area for a long time. The University of Turku has lead four conservation projects in the panda habitat of Sichuan together with the State Forestry and Grassland Administration (SFGA) of China and the CCRCGP in 1998-2008. Two pandas were able to be transferred to Finland as the outcome of this collaboration, and the CCRCGP also participated in this project and will be participating in up-coming projects, too.
How does unicellular life transition to multicellular life? The research team of Professor Lutz Becks at the Limnological Institute of the University of Konstanz has taken a major step forward in explaining this very complex process. They were able to demonstrate - in collaboration with a colleague from the Alfred Wegner Institute (AWI) - that the unicellular green algae Chlamydomonas reinhardtii, over only 500 generations, develops mutations that provide the first step towards multicellular life. This experimentally confirmed a theory on the origin of multicellular life, which says that the evolution of cell groups and the subsequent steps towards multicellularity can only take place when cell groups are both better at reproduction and more likely to survive than single cells. These findings have been published in the current edition of Nature Communications from 9 July 2021.
How sweet it is: Study finds songbirds CAN taste sugar
Having a sweet tooth may be a good thing--if you're a songbird
CORNELL UNIVERSITY
VIDEO: FOOTAGE OF A NEW HOLLAND HONEYEATER (PHYLIDONYRIS NOVAEHOLLANDIAE) DRINKING NECTAR FROM FLOWERS OUTSIDE DEAKIN UNIVERSITY, AUSTRALIA (SLOWED FOR VIEWING).view more
CREDIT: ALEJANDRO RICO-GUEVARA
Contrary to conventional thought, songbirds can taste sugar--even though songbirds are the descendants of meat-eating dinosaurs and are missing a key protein that allows humans and many other animals to taste sweetness. An international team investigated how many bird species can taste sweet and how far back that ability evolved. Their work was published today in the journal Science.
The researchers offered two species of songbirds a choice between sugar water and plain water--nectar-taking honeyeaters, as well as canaries, a grain-eating bird not known for consuming sweet foods. They also examined taste receptor responses sampled from a variety of other species. Regardless of whether their main diet consisted of seeds, grains, or insects, songbird taste receptors responded to sugars.
"This was a clear hint that we should concentrate on a range of songbirds, not only the nectar-specialized ones, when searching for the origins of avian sweet taste," explains senior author Maude Baldwin at the Max Planck Institute for Ornithology in Germany. Baldwin led this study with Yasuka Toda from Meiji University in Japan.
Sugar is a vital carbohydrate providing lots of energy and may have had far-reaching effects on songbird evolution. Though it is thought that most bird lineages can't taste sweetness at all, the scientists now believe that songbirds, which account for more than 40% of the world's bird species, can actually taste sweet, and that sugary food sources may have contributed to their success.
CAPTION
A New Holland Honeyeater(Phylidonyris novaehollandiae) perched on a banksia in Western Australia. Photograph by Gerald Allen, Macaulay Libraryat the Cornell Lab of Ornithology
CREDIT
Gerald Allen, Macaulay Library at the Cornell Lab of Ornithology
Baldwin and Toda dug down to the molecular level to understand the modifications to the "umami" taste receptor that enabled sweet perception among songbirds.
"Because sugar detection is complex, we needed to analyze more than one hundred receptor variants to reveal the molecular mechanisms underlying the sugar responses," says Toda. These exact changes coincide only slightly with those seen in the distantly-related hummingbirds, even though similar areas of the receptor are modified.
Though songbirds evolved similar workarounds to taste sweetness, they did so at different times, in different places, and in slightly different ways--an example of "convergent evolution." Some songbirds, such as honeyeaters, sunbirds, honeycreepers, and flowerpiercers are now just as dependent on nectar as the hummingbirds.
"This study fundamentally changes the way we think about the sensory perceptions of nearly half the world's birds," says study co-author Eliot Miller at the Cornell Lab of Ornithology. "It demonstrates that most songbirds definitely can taste sweet and got there by following nearly the same evolutionary path that hummingbirds did--it's a neat story about how convergence happens."
Exploring the songbird family tree, the researchers conclude that songbirds evolved to sense sweetness approximately 30 million years ago, before the early ancestors of songbirds left Australia, where all songbirds originated. Even after songbirds radiated across the world, they kept their ability to taste sugar.
Researchers in Japan, Germany, the United States, Hong Kong, and Australia participated in this study. Future studies will explore how sweet perception has coevolved with other physiological traits, such as changes in digestion and metabolism, across bird evolution.
CAPTION
Atlantic Canary (Serinus canaria), a granivorous songbird (also called Island Canary).
CREDIT
Martin Flack, Macaulay Library at the Cornell Lab of Ornithology.
NIST uses method to understand the molecular underpinnings of a disease affecting corals
NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY (NIST)
IMAGE: A CORAL DISEASE CALLED GROWTH ANOMALIES (GAS) IS DEPICTED HERE IN THE CORAL SPECIES PORITES COMPRESSA, A REEF BUILDING SPECIES FOUND OFF THE COAST OF HAWAII. GAS ARE A TUMOR-LIKE... view more
CREDIT: E. ANDERSSON/NIST
Coral reefs are a favorite spot for scuba divers and are among the world's most diverse ecosystems. For example, the Hawaiian coral reefs, known as the "rainforests of the sea," host over 7,000 species of marine animals, fishes, birds and plants. But coral reefs are facing serious threats, including a number of diseases that have been linked to human activity.
To understand the connection between human activity and a type of tumorlike disease called growth anomalies (GAs), researchers at the National Institute of Standards and Technology (NIST) have collaborated with the U.S Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA) to use an emerging molecular profiling method to identify 18 small molecules that promise to help them better understand the series of molecular reactions that lead to the disease.
GAs affect both the coral skeleton and its soft tissues. Scientists don't know the cause of the disease or how it spreads but have hypothesized that there is a strong correlation between GA prevalence in coral colonies and human population density nearby.
Almost all types of corals are made of hundreds to millions of individual soft-bodied animals called polyps. The polyps secrete calcium carbonate to form a hard skeleton that lays the foundation for the coral colony. GAs affect corals through irregular and accelerated growth of their skeleton, causing it to be less dense and filled with holes. This results in a tumorlike mass in the skeleton of a coral colony with fewer polyps and a diminished ability to reproduce.
Shallow water corals receive food like carbohydrates and oxygen as a byproduct of photosynthesis from the symbiotic relationship they have with zooxanthellae, photosynthetic algae that live inside coral tissues. GAs can lead to fewer symbiotic zooxanthellae and therefore less energy being absorbed from photosynthesis.
Even though GAs do not typically directly lead to coral death, they do affect the overall health of coral colonies and can pose an ecological threat to coral populations. To analyze the disease, NIST researchers chose the coral species Porites compressa as their target sample.
This coral species is known as the "finger" or "hump" coral and is part of the stony coral family, which is "one of the important reef-building species in Hawaii," said NIST chemist Tracey Schock. "They lay the foundation for the coral reef."
P. compressa is found in shallow lagoons off the Hawaiian Islands, and the researchers obtained their coral samples from Kaneohe Bay, Oahu. The bay has been studied widely as a site affected by human activity such as sewage discharge and metal pollution. GAs have previously been observed in the coral species there.
In order to analyze and study GAs in P. compressa, researchers turned to the field of metabolomics, which is the study of small molecules, such as those making up living organisms found in tissues, blood or urine. These small molecules, known as metabolites, are the intermediate and end products in a linked series of biochemical reactions known as molecular pathways in an organism.
Some examples of such small molecules include sugars like glucose, amino acids, lipids and fatty acids. Their production can be influenced by genetic and environmental factors and can help researchers better understand the biochemical activity of tissue or cells. In this case, chemical analysis of metabolites provides significant information that helps researchers understand the physiology of the disease.
For their study, researchers sampled a coral colony that had both healthy and diseased tissue. They split up their samples so they could assess the healthy coral and diseased coral separately. They also had a separate adjacent sample that was free of diseased tissue.
The samples were frozen in liquid nitrogen, and then freeze-dried for practical sample processing while maintaining metabolic integrity. The researchers then separated the diseased parts from the healthy colony using a hammer and stainless-steel chisel and collected the tissue from the skeleton with a brush. In one of the final stages of the sample preparation, they chemically extracted the metabolites from the coral tissue using a combination of methanol, water and chloroform.
"The method is novel for coral studies," said Schock. "With metabolomics, it is critical to preserve the state of all metabolites in a sample at the time of collection. This requires halting all biochemical activity using liquid nitrogen and maintaining this state until chemical extraction of the metabolome. The complexity of a coral structure necessitates stringent collection and processing protocols."
The researchers then produced a metabolomic analysis of the coral samples by using a reproducible profiling technique known as proton nuclear magnetic resonance (1H NMR).
The 1H NMR technique exposes the coral extract to electromagnetic fields and measures the radio frequency signals released by the hydrogens in the sample. The various kinds of metabolites are revealed by their unique signals which inform of their chemical environment. NMR detects all signals from the magnetic nuclei within a sample, making it an unbiased "all-in-one" technique. Two-dimensional NMR experiments that can identify both hydrogens (1H) and their directly bound carbon (13C) atoms provide more chemical information, giving confidence in the accuracy of the identities of the various metabolites within a sample.
The study identified 18 different metabolites and a new GA morphological form in P. compressa. The researchers found that GA tumors have distinct metabolite profiles compared with healthy areas of the same coral colony and detected specific metabolites and metabolic pathways that may be important for these profile differences. They also discovered that the loss of internal pH regulation is seemingly responsible for the hollow skeletons that are a characteristic of GAs.
"We have not only characterized new aspects of GA physiology, but have also discovered candidate pathways that provide a clear path forward for future research efforts aiming to further understand GA formation and coral metabolism, in general," said Schock.
As studies of this type accumulate, the researchers envision a database that could pull together coral metabolite information from multiple coral species into an accessible location for all scientists.
Collaborating with other researchers in different fields could increase understanding of the biological impacts of this disease on coral colonies. "We are going to learn which species are tolerant and which species are sensitive to stresses, and the physiological adaptations or mechanisms of both types will be important to conservation efforts," said Schock.
For now, the researchers hope these findings will be helpful for other scientists analyzing coral species and ultimately be beneficial for the coral reefs themselves, potentially aiding efforts to better preserve them.
CAPTION
Two different field images depicting the coral species Porites compressa, a reef building coral off of the coast of Hawaii. The corals are affected by growth anomalies (GAs), a disease that can cause tumor-like protrusions that affect both the coral skeleton and its soft tissue. The GAs are the "larger protrusions" on the corals.
CREDIT
R. Day/NIST
Major revamp of SNAP could eliminate food insecurity in the US
UNIVERSITY OF ILLINOIS COLLEGE OF AGRICULTURAL, CONSUMER AND ENVIRONMENTAL SCIENCES
IMAGE: MILLIONS OF AMERICANS LACK ADEQUATE ACCESS TO HEALTHY FOOD. EXPANDING SNAP BENEFITS AND ELIGIBILITY COULD ELIMINATE FOOD INSECURITY IN THE UNITED STATES, SUGGESTS UNIVERSITY OF ILLINOIS PROFESSOR CRAIG GUNDERSEN. view more
CREDIT: COLLEGE OF ACES, UNIVERSITY OF ILLINOIS.
URBANA, Ill. - Food insecurity is a major problem in the U.S., and it worsened during the COVID-19 pandemic. The Supplemental Nutrition Assistance Program (SNAP) provides some relief, but millions of Americans still lack adequate access to healthy food. A new study from the University of Illinois proposes a potential solution.
"Restructuring SNAP as a Universal Basic Income (UBI) program or modified UBI is a straightforward way to eliminate food insecurity in United States. It's expensive but it is not difficult," says Craig Gundersen, distinguished professor in the Department of Agricultural and Consumer Economics at U of I. Gundersen authored the study, published in Food Policy.
While the existing SNAP program effectively reduces food insecurity, it has some limitations. For some SNAP recipients, the amount of aid they receive is insufficient. Some people who are food insecure and eligible for SNAP do not participate. And finally, more than half of those who are food insecure are not eligible for SNAP, Gundersen explains.
Using data from the 2019 Current Population Survey, Gundersen estimates the effects of expanding SNAP to become a UBI program under three different scenarios.
"The first scenario is a standard UBI program, where everybody in the United States gets SNAP at the maximum level," Gundersen explains. "Under the current program, your SNAP benefits go down if your income increases. Under this proposal, the amount would remain the same. If people wanted to work more and earn more money, they wouldn't lose their SNAP benefits."
Under this scenario, food insecurity could decline by 88.8 %, assuming the $730 billion cost would be funded through higher taxes for top-earning households.
"With the current distribution of taxes in the United States, the top 10% of incomes pay 70% of the taxes, and the top 50% pay 97%. Even if you were to raise taxes on the higher-income brackets to implement this program, it is unlikely to influence the probability of these households becoming food insecure," he states.
The second scenario in Gundersen's study would be a modified UBI program where households with incomes up to four times the poverty line; that is, approximately $100,000 for a family of four, would receive SNAP benefits.
Compared to the first scenario, the decline in food insecurity would be almost the same - 88.5% ¬ - but at a much lower cost of $408.5 billion.
Gundersen's third scenario addresses the issue that current SNAP benefits are not enough for some recipients to become food secure.
"Under this scenario, I consider what would happen if we increase the maximum SNAP benefit by 25% and give it to all households with incomes up to about $100,000 a year. In that case, there would be a 98.2% decline in food insecurity, and the cost would be $564.5 billion," he notes.
"I believe the third scenario is the best one," Gundersen says. "While the second one is also good, it would not be adequate for some of the most vulnerable groups; that is, SNAP recipients who need more assistance than they currently receive. The third scenario would ensure that they get what they need to become food secure."
Gundersen acknowledges that his proposals are costly, but so are other government programs.
"Essentially, I propose a way of eliminating food insecurity in United States, and the cost of this would be about a half trillion dollars per year. That seems like a lot, but to put it in context, the cost of the COVID-19 pandemic stimulus packages from the Trump administration and the Biden administration were roughly $6 trillion. It's a lot of money. But if we want to be serious about alleviating food insecurity, this is a simple, straightforward way to do it," he concludes.
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The Department of Agricultural and Consumer Economics is in the College of Agricultural, Consumer and Environmental Sciences, University of Illinois.
Gundersen's paper, "Viewpoint: A proposal to reconstruct the Supplemental Nutrition Assistance Program (SNAP) into a universal basic income program for food," is published in Food Policy. [https://doi.org/10.1016/j.foodpol.2021.102096].
Huge volcanic eruption disrupted climate but not human evolution
IMAGE: THE RUTGERS-LED RESEARCHERS EXAMINED EXPLOSIVE ASH DEPOSITS THAT ARE TENS OF METERS THICK ABOUT 35 KM NORTH OF THE TOBA CALDERA IN INDONESIA. view more
CREDIT: STEVE SELF, UC BERKELEY
New Brunswick, N.J. (July 9, 2021) -- A massive volcanic eruption in Indonesia about 74,000 years ago likely caused severe climate disruption in many areas of the globe, but early human populations were sheltered from the worst effects, according to a Rutgers-led study.
The eruption of the Toba volcano was the largest volcanic eruption in the past two million years, but its impacts on climate and human evolution have been unclear. Resolving this debate is important for understanding environmental changes during a key interval in human evolution.
"We were able to use a large number of climate model simulations to resolve what seemed like a paradox," said lead author Benjamin Black, an assistant professor in the Department of Earth and Planetary Sciences at Rutgers University-New Brunswick. "We know this eruption happened and that past climate modeling has suggested the climate consequences could have been severe, but archaeological and paleoclimate records from Africa don't show such a dramatic response.
"Our results suggest that we might not have been looking in the right place to see the climate response. Africa and India are relatively sheltered, whereas North America, Europe and Asia bear the brunt of the cooling," Black said. "One intriguing aspect of this is that Neanderthals and Denisovans were living in Europe and Asia at this time, so our paper suggests evaluating the effects of the Toba eruption on those populations could merit future investigation."
The researchers analyzed 42 global climate model simulations in which they varied magnitude of sulfur emissions, time of year of the eruption, background climate state and sulfur injection altitude to make a probabilistic assessment of the range of climate disruptions the Toba eruption may have caused. This approach let the team account for some of the unknowns related to the eruption.
"By using a probabilistic approach, we aim at understanding the likelihood that some regions were less impacted by Toba, considering the wide range of estimates of its size and timing, in addition to our lack of knowledge of the underlying climate state," said Black.
The results suggest there was likely significant regional variation in climate impacts. The simulations predict cooling in the Northern Hemisphere of at least 4°C, with regional cooling as high as 10°C depending on the model parameters. In contrast, even under the most severe eruption conditions, cooling in the Southern Hemisphere -- including regions populated by early humans -- was unlikely to exceed 4°C, although regions in southern Africa and India may have seen decreases in precipitation at the highest sulfur emission level.
The results explain independent archaeological evidence suggesting the Toba eruption had modest effects on the development of hominid species in Africa. According to the authors, their ensemble simulation approach could be used to better understand other past and future explosive eruptions.
"Our results reconcile the simulated distribution of climate impacts from the eruption with paleoclimate and archaeological records," according to the study. "This probabilistic view of climate disruption from Earth's most recent super-eruption underscores the uneven expected distribution of societal and environmental impacts from future very large explosive eruptions."
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The study included researchers from the National Center for Atmospheric Research, University of Leeds and University of Cambridge, and was supported by the National Center for Atmospheric Research and the National Science Foundation.
Broadcast interviews: Rutgers University has broadcast-quality TV and radio studios available for remote live or taped interviews with Rutgers experts. For more information, contact John Cramer at john.cramer@rutgers.edu
ABOUT RUTGERS--NEW BRUNSWICK
Rutgers University-New Brunswick is where Rutgers, the State University of New Jersey, began more than 250 years ago. Ranked among the world's top 60 universities, Rutgers's flagship is a leading public research institution and a member of the prestigious Association of American Universities. It has an internationally acclaimed faculty, 12 degree-granting schools and the Big Ten Conference's most diverse student body.
Engineering seeds to resist drought
A new seed-coating process could facilitate agriculture on marginal arid lands by enabling the seeds to retain any available water
As the world continues to warm, many arid regions that already have marginal conditions for agriculture will be increasingly under stress, potentially leading to severe food shortages. Now, researchers at MIT have come up with a promising process for protecting seeds from the stress of water shortage during their crucial germination phase, and even providing the plants with extra nutrition at the same time.
The process, undergoing continued tests in collaboration with researchers in Morocco, is simple and inexpensive, and could be widely deployed in arid regions, the researchers say. The findings are reported this week in the journal Nature Food, in a paper by MIT professor of civil and environmental engineering Benedetto Marelli, MIT doctoral student Augustine Zvinavashe '16, and eight others at MIT and at the King Mohammed VI Polytechnic University in Morocco.
The two-layer coating the team developed is a direct outgrowth of years of research by Marelli and his collaborators in developing seed coatings to confer various benefits. A previous version enabled seeds to resist high salinity in the soil, but the new version is aimed at tackling water shortages.
"We wanted to make a coating that is specific to tackling drought," Marelli explains. "Because there is clear evidence that climate change is going to impact the basin of the Mediterranean area," he says, "we need to develop new technologies that can help to mitigate these changes in the climate patterns that are going to make less water available to agriculture."
The new coating, taking inspiration from natural coatings that occur on some seeds such as chia and basil, is engineered to protect the seeds from drying out. It provides a gel-like coating that tenaciously holds onto any moisture that comes along, and envelops the seed with it.
A second, inner layer of the coating contains preserved microorganisms called rhizobacteria, and some nutrients to help them grow. When exposed to soil and water, the microbes will fix nitrogen into the soil, providing the growing seedling with nutritious fertilizer to help it along.
"Our idea was to provide multiple functions to the seed coating," Marelli says, "not only targeting this water jacket, but also targeting the rhizobacteria. This is the real added value to our seed coating, because these are self-replicating microorganisms that can fix nitrogen for the plants, so they can decrease the amount of nitrogen-based fertilizers that are provided, and enrich the soil."
Early tests using soil from Moroccan test farms have shown encouraging results, the researchers say, and now field tests of the seeds are underway.
Ultimately, if the coatings prove their value through further tests, the coatings are simple enough that they could be applied at a local level, even in remote locations in the developing world. "It can be done locally," Zvinavashe says. "That's one of the things we were thinking about while we were designing this. The first layer you could dip coat, and then the second layer, you can spray it on. These are very simple processes that farmers could do on their own." In general, though, Zvinavashe says it would be more economical to do the coatings centrally, in facilities that can more easily preserve and stabilize the nitrogen-fixing bacteria.
The materials needed for the coatings are readily available and often used in the food industry already, Marelli says. The materials are also fully biodegradable, and some of the compounds themselves can actually be derived from food waste, enabling the eventual possibility of closed-loop systems that continuously recycle their own waste.
Although the process would add a small amount to the cost of the seeds themselves, Marelli says, it may also produce savings by reducing the need for water and fertilizer. The net balance of costs and benefits remains to be determined through further research.
Although initial tests using common beans have shown promising results by a variety of measures, including root mass, stem height, chlorophyll content, and other metrics, the team has not yet cultivated a full crop from seeds with the new coating all the way through to harvest, which will be the ultimate test of its value. Assuming that it does improve harvest yields under arid conditions, the next step will be to extend the research to a variety of other important crop seeds, the researchers say.
"The system is so simple that it can be applied to any seed," Marelli says. "And we can design the seed coating to respond to different climate patterns." It might even be possible to tailor coatings to the predicted rainfall of a particular growing season, he says.
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The team included Julie Laurent, Salma Mouhib, Hui Sun, Henri Manu Effa Fouda, Doyoon Kim, Manal Mhada, and Lamfeddal Kouisni at MIT and at King Mohammad VI Polytechnic University in Ben-Guerir, Morocco. The work was partly supported by the U.S. Office of Naval Research, the National Science Foundation, and the MIT Paul M. Cook Career Development Professorship.
Written by David L. Chandler, MIT News Office
First genetic evidence from medieval plague victims suggests Black Death reached Southern Italy
EUROPEAN SOCIETY OF CLINICAL MICROBIOLOGY AND INFECTIOUS DISEASES
Graves containing the remains of two men (aged between 30 and 45 years) are the first evidence of Yersinia pestis infection, the bacteria responsible for plague, in 14th-century Southern Italy, according to new research being presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID).
"The retrieval of plague ancient DNA from the teeth of two adults buried at the Abbey of San Leonardo in Siponto is a discovery of national importance, as it is the first related to the second plague pandemic (Black Death) in Southern Italy", says Dr Donato Raele from the Istituto Zooprofilattico Sperimentale of Puglia and Basilicata in Foggia, who led the research.
"We were very suspicious when we unearthed 14th-century coins from the clothing of one victim and more hidden in a bag tied around the waist of the other, which suggests that the bodies were not inspected to confirm cause of death."
In the mid-14th century Europe was devastated by the Black Death, a major plague pandemic that wiped out up to 60% of the population. The plague reached the shores of Sicily in 1347, and ravaged large cities and towns in northern and central Italy. When the first wave of Black death had been concluded in the winter of 1348, more than a third of Italy's population had died. Although cases of Black Death are reported in several historical documents no burial sites have undergone DNA analysis in the South of Italy.
The Abbey of San Leonardo in Siponto (Apulia, Southern Italy) was an important religious and medical centre during the Middle Ages where traders and travellers stopped to rest and recuperate. It was a crossroads for pilgrims heading along the Via Francigena to the Sanctuary of Monte Sant'Angelo, and for merchants passing through the harbour of Manfredonia.
The two single graves were discovered during an excavation of a section of the Abbey's cemetery that was used for burial at the end of the 13th beginning of the 14th century.
The first victim was a male (30-35 years old). He wore a belt with a rectangular iron buckle with a shaft, found flattened on his right femur. Most likely tied to this belt was a small bag which contained 12 denarii (Roman silver coins) found still stacked under his leg.
The second victim was an adult male (45 years old). He was buried fully clothed and had some personal items on him including iron and bronze rings, one with pitting, and the end of a lace; and numerous grains of dark vitreous material in his left hand that could be a rosary.
The man guarded 99 alloy Deniers tournois coins from Frankish Greece (last decades of the 13th century - the first quarter of the 14th century) and one silver Gigliato issued in name of Robert of Anjou (1309-1343), found in piles, probably inside bags hidden in various parts of his clothes.
Given that the dating of the burial and coins fits the arrival of the Second Pandemic in Europe, the experts suspected that the adults might have died during the Black Death or from other infectious diseases that were prevalent at the time, such as malaria, tuberculosis, or epidemic typhus and Malta fever (brucellosis).
To provide more evidence, three teeth from each individual were sent to the Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata for DNA analysis, along with two additional unrelated human teeth (negative controls).
Four teeth of the adults in the graves tested positive for Y. pestis, and were highly similar to previously investigated plague victims from other parts of Italy and had identical strains of Y. pestis.
"The Abbey of San Leonardo was a key point along a system of pathways that formed part of The Via Francigena, a major medieval pilgrimage route to Rome from the north, and was an ideal site from which plague could be spread", says Raele.
"We haven't yet fully figured out the extent of pandemic waves during the Black Death in the south of Italy. In fact, the DNA of Y. pestis is about 300 years older than the previous one linked to a mass grave dating back to the late 1600s and reported by our researchers in Foggia. Consequently, our results contains precious details to better understand the magnitude of plague throughout Italy."
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Antibiotic resistance -- How many more final warnings before it's too late?
EUROPEAN SOCIETY OF CLINICAL MICROBIOLOGY AND INFECTIOUS DISEASES
A special WHO-sanctioned session at this year's European Congress on Clinical Microbiology & Infectious Diseases (ECCMID) will ask how many more warnings the world needs before it is too late to address the growing threat of antimicrobial resistance (AMR), increasing in all areas of medicine.
A panel that includes the former Chief Medical Officer for England, Professor Dame Sally Davies (now the UK Special Envoy on AMR) will look at the scant progress made in recent years despite the multiple calls to action and warnings of an antibiotic apocalypse threatening all of the modern medicine we depend on for daily life.
"Time and again, the alarm bells have sounded for the broken antibiotic market. Compared to $8billion of profit for cancer drugs, the $100million loss for antimicrobials means that our medicine cabinets are becoming emptier - because of bankruptcies, not lack of scientific brainpower," explains Dame Sally. "As it stands, the weak market and lack of access leaves patients paying. And future generations will suffer even more."
This trend is, she says, not sustainable, especially when COVID-19 shows how much patients globally depend on scientific innovation. "I have been saying that 'there is no time to wait', but for many it is already too late - they have died. Unless we act now, the alarm bells will soon turn into the death knell for modern medicine," says Dame Sally.
With more innovation, experts believe AMR is containable. Last month, the G7 nations committed to strengthen research and development for new antibiotics. In the US, The PASTEUR Act (which is pending a vote by the US Government House of Representatives and Congress) represents a game-changing mechanism to 'pull' through new antibiotics so that they reach the patients who need them most.
The hope that the PASTEUR Act offers is plain to see - under this legislation, the US Federal Government would provide market incentives to develop lifesaving antimicrobial drugs. Pharmaceutical companies/developers would be paid contractually agreed amounts annually, for an agreed period between five years up to the antimicrobial's patent life. These contracts would promote the development of new antimicrobials.
Specifically, such contracts would promote the development of antimicrobials against the 'superbugs' considered the most threatening by the US Centers for Disease Control and Prevention (CDC) including Candida auris, a fungus, and bacteria such as Clostridioides difficile and carbapenem-resistant Acinetobacter. The PASTEUR-based contracts would also act as an incentive to develop new classes of antimicrobials with completely new mechanisms of action to turn the tide against these drug-resistant infections.
The UK, meanwhile, has launched a world-first 'Netflix-style' payment model, that will pay pharmaceutical companies a fixed amount by subscription for access to their innovative antibiotic products, rather than fees based on how much product is used. In December 2020 the UK Government selected two antimicrobials - Shionogi's Fetcroja (Cefiderocol) and Pfizer's Zavicefta (ceftazidime with avibactam) (Zavicefta), to be purchased via the Netflix-style subscription payment model. The European Union's Pharmaceutical Strategy published in 2020 also commits to implementing a new 'pull' model to further boost the ailing new antimicrobial pipeline.
Dame Sally concludes: "It is our collective responsibility to ensure that our research and policy-making reflects this. From early-stage research, to clinical trials, to patient access, inclusivity must define our innovation. Globally, we need to we move forward together, working in partnership across sectors and countries."
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