Finding the brain’s compass

The world is constantly bombarding our senses with information, but the ways in which our brain extracts meaning from this information remains elusive. How do neurons transform raw visual input into a mental representation of an object — like a chair or a dog?

In work published in Nature Neuroscience, MIT neuroscientists have identified a brain circuit in mice that distills “high-dimensional” complex information about the environment into a simple abstract object in the brain.

“There are no degree markings in the external world; our current head direction has to be extracted, computed, and estimated by the brain,” explains Ila Fiete, an associate member of the McGovern Institute and senior author of the paper. “The approaches we used allowed us to demonstrate the emergence of a low-dimensional concept, essentially an abstract compass in the brain.”

This abstract compass, according to the researchers, is a one-dimensional ring that represents the current direction of the head relative to the external world.

A circuit of thousands of neurons in the mammalian brain traces out a spare one-dimensional ring during complex navigation behaviors in 3-D space (blue), representing an internal compass. At any time, the circuit state is one dot along the compass, representing the present estimated direction of heading in the external world. During deep, non-REM sleep (yellow), the circuit traces out the same ring, but scaled differently in size, to define a whole cone.

Video: Ila Fiete

Schooling fish

Trying to show that a data cloud has a simple shape, like a ring, is a bit like watching a school of fish. By tracking one or two sardines, you might not see a pattern. But if you could map all of the sardines, and transform the noisy dataset into points representing the positions of the whole school of sardines over time, and where each fish is relative to its neighbors, a pattern would emerge. This model would reveal a ring shape, a simple shape formed by the activity of hundreds of individual fish.

Fiete, who is also an associate professor in MIT’s Department of Brain and Cognitive Sciences, used a similar approach, called topological modeling, to transform the activity of large populations of noisy neurons into a data cloud in the shape of a ring.

Simple and persistent ring

Previous work in fly brains revealed a physical ellipsoid ring of neurons representing changes in the direction of the fly’s head, and researchers suspected that such a system might also exist in mammals.

In this new mouse study, Fiete and her colleagues measured hours of neural activity from scores of neurons in the anterodorsal thalamic nucleus (ADN) — a region believed to play a role in spatial navigation — as the animals moved freely around their environment. They mapped how the neurons in the ADN circuit fired as the animal’s head changed direction.

Together, these data points formed a cloud in the shape of a simple and persistent ring.

“This tells us a lot about how neural networks are organized in the brain,” explains Edvard Moser, director of the Kavli Institute of Systems Neuroscience in Norway, who was not involved in the study. “Past data have indirectly pointed towards such a ring-like organization, but only now has it been possible, with the right cell numbers and methods, to demonstrate it convincingly,” says Moser.

Their method for characterizing the shape of the data cloud allowed Fiete and colleagues to determine which variable the circuit was devoted to representing, and to decode this variable over time, using only the neural responses.

“The animal’s doing really complicated stuff,” explains Fiete, “but this circuit is devoted to integrating the animal’s speed along a one-dimensional compass that encodes head direction. Without a manifold approach, which captures the whole state space, you wouldn’t know that this circuit of thousands of neurons is encoding only this one aspect of the complex behavior, and not encoding any other variables at the same time.”

Even during sleep, when the circuit is not being bombarded with external information, this circuit robustly traces out the same one-dimensional ring, as if dreaming of past head-direction trajectories.

Further analysis revealed that the ring acts an attractor. If neurons stray off trajectory, they are drawn back to it, quickly correcting the system. This attractor property of the ring means that the representation of head direction in abstract space is reliably stable over time, a key requirement if we are to understand and maintain a stable sense of where our head is relative to the world around us.

“In the absence of this ring,” Fiete explains, “we would be lost in the world.”

Shaping the future

Fiete’s work provides a first glimpse into how complex sensory information is distilled into a simple concept in the mind, and how that representation autonomously corrects errors, making it exquisitely stable.

But the implications of this study go beyond coding of head direction.

“Similar organization is probably present for other cognitive functions, so the paper is likely to inspire numerous new studies,” says Moser.

Fiete sees these analyses and related studies carried out by colleagues at the Norwegian University of Science and Technology, Princeton University, the Weitzman Institute, and elsewhere as fundamental to the future of neural decoding studies.

With this approach, she explains, it is possible to extract abstract representations of the mind from the brain, potentially even thoughts and dreams.

“We’ve found that the brain deconstructs and represents complex things in the world with simple shapes,” explains Fiete. “Manifold-level analysis can help us to find those shapes, and they almost certainly exist beyond head-direction circuits.”


Source

Blue sharks use ocean eddies as fast-tracks to food

Research News

Blue sharks use ocean eddies as fast-tracks to food

Swirling currents mark fish-filled ocean twilight zone

Blue sharks

Blue sharks follow swirling currents called ocean eddies to find food.

August 12, 2019

Blue sharks use large, swirling ocean currents known as eddies to fast-track their way to food in the twilight zone — a layer of the sea between 200 and 1,000 meters deep, according to new research by scientists at the Woods Hole Oceanographic Institution and the University of Washington. The results show that animals can read subtle ocean cues and follow them to where food is concentrated.

The findings were published in the journal Proceedings of the National Academy of Sciences.

The research revealed that blue sharks spent a good portion of their days using these whirling pockets of warm water to find prey. Camrin Braun, a University of Washington marine ecologist and lead author of the study, says the behavior of the blue sharks was similar to that of white sharks the team tracked in a study last year.

However, the two species had different preferences when it came to water temperature. White sharks, which are warm-blooded animals, used a combination of warm- and cold-water eddies to locate food in the twilight zone, while blue sharks — a cold-blooded species — relied exclusively on warm-water eddies.

“Blue sharks can’t regulate their body temperature internally to stay warmer than the ambient seawater like white sharks can,” said Braun. “We think that’s why they show a clear preference for warm-water eddies.”

“This finding came out of research focusing on how the physics of ocean eddies organizes biological activity,” says Mete Uz, a program director in NSF’s Division of Ocean Sciences, which funded the research. “The ocean may appear to our eye as a vast, featureless expanse, but the animals that live in it know how to read subtle cues and follow them to where their food is concentrated.”

—  NSF Public Affairs, (703) 292-8070 media@nsf.gov

Source

Air pollution can accelerate lung disease as much as a pack a day of cigarettes

Air pollution — especially ozone air pollution which is increasing with climate change — accelerates the progression of emphysema of the lung, according to a new study led by the University of Washington, Columbia University and the University at Buffalo.

While previous studies have shown a clear connection of air pollutants with some heart and lung diseases, the new research published Aug. 13 in JAMA demonstrates an association between long-term exposure to all major air pollutants — especially ozone — with an increase in emphysema seen on lung scans. Emphysema is a condition in which destruction of lung tissue leads to wheezing, coughing and shortness of breath, and increases the risk of death.

“We were surprised to see how strong air pollution’s impact was on the progression of emphysema on lung scans, in the same league as the effects of cigarette smoking, which is by far the best-known cause of emphysema,” said the study’s senior co-author, Dr. Joel Kaufman, UW professor of environmental and occupational health sciences and epidemiology in the School of Public Health.

In fact, the researchers found, if the ambient ozone level was 3 parts per billion higher where you live compared to another location over 10 years, that was associated with an increase in emphysema roughly the equivalent of smoking a pack of cigarettes a day for 29 years. And the study determined that ozone levels in some major U.S. cities are increasing by that amount, due in part to climate change. The annual averages of ozone levels in study areas were between about 10 and 25 ppb.

“Rates of chronic lung disease in this country are going up and increasingly it is recognized that this disease occurs in nonsmokers,” said Kaufman, also a professor of internal medicine and a physician at UW School of Medicine. “We really need to understand what’s causing chronic lung disease, and it appears that air pollution exposures that are common and hard to avoid might be a major contributor.”

The results are based on an extensive, 18-year study involving more than 7,000 people and a detailed examination of the air pollution they encountered between 2000 and 2018 in six metropolitan regions across the U.S.: Chicago, Winston-Salem, N.C., Baltimore, Los Angeles, St. Paul, Minnesota, and New York. The participants were drawn from the Multi-Ethnic Study of Atherosclerosis (MESA) Air and Lung studies.

“To our knowledge, this is the first longitudinal study to assess the association between long-term exposure to air pollutants and progression of percent emphysema in a large, community-based, multi-ethnic cohort,” said first author Meng Wang, an assistant professor of epidemiology and environmental health at the University at Buffalo who conducted the research as a postdoctoral researcher at the UW.

The authors developed novel and accurate exposure assessment methods for air pollution levels at the homes of study participants, collecting detailed measurement of exposures over years in these metropolitan regions, and measurements at the homes of many of the participants. This work in the MESA Air study was led at the University of Washington. While most of the airborne pollutants are in decline because of successful efforts to reduce them, ozone has been increasing, the study found. Ground-level ozone is mostly produced when ultraviolet light reacts with pollutants from fossil fuels.

“This is a big study with state-of-the-art analysis of more than 15,000 CT scans repeated on thousands of people over as long as 18 years. These findings matter since ground-level ozone levels are rising, and the amount of emphysema on CT scans predicts hospitalization from and deaths due to chronic lung disease,” said Dr. R. Graham Barr, professor of medicine and epidemiology at Columbia University who led the MESA Lung study and is a senior author of the paper.

“As temperatures rise with climate change,” Barr explained, “ground-level ozone will continue to increase unless steps are taken to reduce this pollutant. But it’s not clear what level of the air pollutants, if any, is safe for human health.”

Emphysema was measured from CT scans that identify holes in the small air sacs of the participants’ lungs, and lung function tests, which measure the speed and amount of air breathed in and out.

“This study adds to growing evidence of a link between air pollution and emphysema. A better understanding of the impact of pollutants on the lung could lead to more effective ways of preventing and treating this devastating disease,” said James Kiley, director of the Division of Lung Diseases at the National Heart, Lung, and Blood Institute, part of the National Institutes of Health.

“It’s important that we continue to explore factors that impact emphysema,” Kiley added, “particularly in a large, well-characterized multi-ethnic group of adults such as those represented by MESA.”

Source

Cross-border Innovation Procurement in Health: EU funding opportunities & best practices – 17 October 2019, Brussels

The European Commission’s Directorates-General for Research and Innovation (RTD) and for Communications Networks, Content and Technology (CNECT) are hosting the workshop ‘Cross-border Innovation Procurement in Health: EU funding opportunities & best practices’.

Designing, procuring and deploying innovative solutions is an important component of every public sector modernisation strategy, especially in the health and care sector. However, the EU health service providers face many challenges, such as funding, a fragmented legal framework, lack of common standards or interoperability and varying user/patient preferences across the EU.

Through this workshop, we expect to attract a representative audience (procurers, potential suppliers, regions or umbrella organisations and regulators) to discuss how such challenges can be addressed through existing EU Innovation Procurement instruments in the area of health, such as Pre-Commercial Procurement (PCP) and Public Procurement of Innovative solutions (PPI). We will present the new PCP & PPI funding opportunities for 2020 and discuss how to best design and implement successful projects. A networking session is foreseen during the event.

In order to express your interest in the event, please submit your pre-registration.

Source

Events – Europe That Protects: Safeguarding Our Planet, Safeguarding Our Health – 3-4 December 2019, Finnish Institute for Health and Welfare (THL), Mannerheimintie 166, Helsinki, Finland

Europe That Protects: Safeguarding Our Planet, Safeguarding Our Health

3-4 December 2019, Finnish Institute for Health and Welfare (THL), Mannerheimintie 166, Helsinki, Finland

This conference will bring together relevant stakeholders including researchers, policy makers and regulators to identify and discuss the main scientific challenges for harvesting and enhancing the benefits of a sound environment for human health and the scientific challenges for solutions to overcome environmental threats to human health.

The main outcome will be recommendations on research and innovation priorities for the EU and Member States to work together to protect human health and our planet. 

This event is co-organised by the Finnish Institute for Health and Welfare, the Finnish Environment Institute and the European Commission under the auspices of Finland’s Presidency of the EU in 2019.

Source

Outstanding MIT students of French explore "Paris et la rue"

Think of Paris, and images materialize of sublime art and cosmopolitan sophistication. “We all romanticize the culture, and it’s fine to do that,” says Bruno Perreau, the Cynthia L. Reed Professor and associate professor of French studies. “But we also need to add different layers and rethink the connection between myth and reality,” he says.

In search of this connection, Perreau brought seven students to Paris for the annual January Scholars in France program, offered during MIT’s independent activities period. Chosen through a competitive process, the January Scholars students are among the best in MIT’s French studies and language program, and spoke exclusively in French during their stay in Paris. For their travels, the students receive airfare, lodging in a youth hostel, transportation and meals, courtesy of the French Initiatives Endowment Fund.

Led by expert local guides, the group pursued a theme, “Paris et la rue” (Paris and the street), which took them beyond the usual tourist spots and into lesser-known residential and business neighborhoods. During walking tours, the students peeled back layers of history, learned about city planning past and present, and glimpsed behind-the-scenes views of workaday, contemporary Paris. They explored the history of street revolutions in 18th and 19th century Paris, issues of public transportation, new architectural projects, and street art.  It was an itinerary that encouraged students “to encounter aspects of Parisian life they couldn’t have imagined,” says Perreau.
 
Another side of Paris

“We got to learn about things like the design process behind the trash cans and the type of barricades built by revolting Parisians from the 17th straight through to the 20th century,” recounts Anelise Newman, a junior majoring in electrical engineering and computer science.

“We saw parts of the city, like the business sector and the atelier and works of Raymond Moretti … and most importantly, we got to interact with Parisians not as tourists, but as students who were genuinely interested in learning the culture and mastering the language,” says Newman, who also wrote a blog post for MIT Admissions about the trip.

Unexpected episodes enlivened and enriched their daily tours. In a visit to the 13th arrondissement, which began in the 19th century as a factory district and is now home to public housing and a vibrant Asian population, the group took in the many giant murals plastered on the sides of buildings.

“We triggered reactions from locals, who argued with us about their favorite or most hated pieces of public art,” recalls Perreau. “Students were surprised about how attached people were to their personal visions of the city.”

At La Defense, a sprawling business district dotted by high-rises with a subterranean infrastructure for highways, parking, and the Metro, the group found unexpected adventure. The city’s chief archivist and a security detail opened a series of locked doors, and descending a stairway with flashlights, revealed a hidden area.

“We were taken underground to see the atelier and works of Raymond Moretti, a sculptor who passed away 13 years ago,” says Rebecca Grekin, a chemical engineering major. “We felt so privileged to be invited into a place that was normally off limits.”

Perreau, who likened the concealed cavern to “a cathedral or grotto,” was astonished to find himself face to face with a gigantic sculpture nicknamed “the monster” because of the roar from nearby subway trains.

“We had this feeling of being explorers,” he says. “I saw another side of Paris that had been concealed from me, even after having lived there for years.”

Pulling back the curtain

Even at some of the more glittery Parisian venues, MIT travelers were able to pull back the curtain and gain unusual perspectives. During a private tour of the Palais Garnier, home to the Paris Opera Ballet, the troupe’s star dancer, Germain Louvet, showed them spaces normally inaccessible to the public: a fake ceiling behind which gentleman from high society once chose dancers with whom to consort, and in the basement, a tank full of water intended in the 19th century to douse fires, but now full of koi fish.

“I grew up dancing in Accra, Ghana and was obsessed by the Paris ballet,” says Sefa Yakpo, a senior double majoring in management science and French. “So first I couldn’t believe I was standing backstage with the étoile (star), and later I was literally speechless when we went out to a café with him and learned about his life,” she says.

To top off this prized experience, the group attended a performance the following night of the ballet Don Quixote at the Bastille Opera, where they witnessed a once-in-a lifetime crowning of a female star dancer.

Yakpo, who had worked in Paris the previous summer for a consultant firm, felt as if she was seeing the city for the first time. “I walked on very familiar streets, but peeling off layers of history and understanding the politics and culture of these places showed me how a city can have many different faces,” she says.

One of Perreau’s goals was to “shift students’ perceptions of Paris and France, to build new understanding” while having fun together and enjoying the many riches the city has to offer. “There is something about pleasure at the heart of the program,” he says.

Perreau may have succeeded in ways he didn’t anticipate. Grekin returned to Boston determined to continue the French experience. “I am going to keep practicing the language with a friend I made on the trip, and start going to the Boston Symphony Orchestra,” she says.

Safpo found the Paris sojourn a balm for the soul. “At MIT, where at times facts and solving problems make life seem clinical, you can forget to embrace something just because it’s beautiful,” she says. “Music, dance, art — things that touch us — are like magic, and Paris reminded me of the importance of that.”

Story prepared by SHASS Communications
Editorial and Design Director: Emily Hiestand
Writer: Leda Zimmerman

Topics: SHASS, France, Global Studies and Languages, Humanities, Faculty, Classes and programs, Students, Undergraduate, Language, Independent Activities Period, School of Humanities Arts and Social Sciences

Source

An emerging view of RNA transcription and splicing

Cells often create compartments to control important biological functions. The nucleus is a prime example; surrounded by a membrane, it houses the genome. Yet cells also harbor enclosures that are not membrane-bound and more transient, like oil droplets in water. Over the past two years, these droplets (called “condensates”) have become increasingly recognized as major players in controlling genes. Now, a team led by Whitehead Institute scientists helps expand this emerging picture with the discovery that condensates play a role in splicing, an essential activity that ensures the genetic code is prepared to be translated into protein. The researchers also reveal how a critical piece of cellular machinery moves between different condensates. The team’s findings appear in the Aug. 7 online issue of Nature.

“Condensates represent a real paradigm shift in the way molecular biologists think about gene control,” says senior author Richard Young, a member of the Whitehead Institute and professor of biology at MIT. “Now, we’ve added a critical new layer to this thinking that enhances our understanding of splicing as well as the major transcriptional apparatus RNA polymerase II.”

Young’s lab has been at the forefront of studying how and when condensates form as well as their functions in gene regulation. In the current study, Young and his colleagues, including first authors Eric Guo and John Manteiga, focused their efforts on a key transition that happens when genes undergo transcription — an early step in gene activation whereby an RNA copy is created from the genes’ DNA template. First, all of the molecular machinery needed to make RNA, including a large protein complex known as RNA polymerase II, assembles at a given gene. Then, specific chemical modifications to RNA polymerase II allow it to begin transcribing DNA into RNA. This shift from so-called transcription initiation to active transcription also involves another important molecular transition: As RNA molecules begin to grow, the splicing apparatus must also move in and carry out its job.

“We wanted to step back and ask, ‘Do condensates play an important role in this switch, and if so, what mechanism might be responsible?’” explains Young.

For roughly three decades, it has been recognized that the factors required for splicing are stored in compartments called speckles. Yet whether these speckles play an active role in splicing, or are simply storage vessels, has remained unclear.

Using confocal microscopy, the Whitehead team discovered condensates filled with components of the splicing machinery in the vicinity of highly active genes. Notably, these structures exhibited similar liquid-like characteristics to those condensates described in prior studies from Young’s lab that are involved in transcription initiation. 

“These findings signaled to us that there are two types of condensates at work here: one involved in transcription initiation and the other in splicing and transcriptional elongation,” said Manteiga, a graduate student in Young’s lab.

With two different condensates at play, the researchers wondered: How does the critical transcriptional machinery, specifically RNA polymerase II, move from one condensate to the other?

Guo, Manteiga, and their colleagues found that chemical modification, specifically the addition of phosphate groups, serves as a kind of molecular switch that alters the protein complex’s affinity for a particular condensate. With fewer phosphate groups, it associates with the condensates for transcription initiation; when more phosphates are added, it enters the splicing condensates. Such phosphorylation occurs on one end of the protein complex, which contains a specialized region known as the C-terminal domain (CTD). Importantly, the CTD lacks a specific three-dimensional structure, and previous work has shown that such intrinsically disordered regions can influence how and when certain proteins are incorporated into condensates.

“It is well-documented that phosphorylation acts as a signal to help regulate the activity of RNA polymerase II,” says Guo, a postdoc in Young’s lab. “Now, we’ve shown that it also acts as a switch to alter the protein’s preference for different condensates.”

In light of their discoveries, the researchers propose a new view of splicing compartments, where speckles serve primarily as warehouses, storing the thousands of molecules required to support the splicing apparatus when they are not needed. But when splicing is active, the phosphorylated CTD of RNA Pol II serves as an attractant, drawing the necessary splicing materials toward the gene where they are needed and into the splicing condensate.

According to Young, this new outlook on gene control has emerged in part through a multidisciplinary approach, bringing together perspectives from biology and physics to learn how properties of matter predict some of the molecular behaviors he and his team have observed experimentally. “Working at the interface of these two fields is incredibly exciting,” says Young. “It is giving us a whole new way of looking at the world of regulatory biology.”

Support for this work was provided by the U.S. National Institutes of Health, National Science Foundation, Cancer Research Institute, Damon Runyon Cancer Research Foundation, Hope Funds for Cancer Research, Swedish Research Council, and German Research Foundation DFG.


Source

Mercury levels in fish are on the rise

Research News

Mercury levels in fish are on the rise

Climate change and overfishing likely to increase human exposure to toxic methylmercury in seafood

model of mercury emissions

Human exposure to mercury through seafood is predicted to increase.

August 9, 2019

Add another item to the ever-growing list of the dangerous impacts of climate change: Warming oceans are leading to an increase of the harmful neurotoxicant methylmercury in popular seafood, including cod, Atlantic bluefin tuna and swordfish, according to research led by researchers at Harvard University.

The scientists developed a first-of-its-kind, comprehensive model that simulates how environmental factors, including increasing ocean temperatures and overfishing, affect levels of methylmercury in fish. The researchers found that, while the regulation of mercury emissions has successfully reduced methylmercury levels in fish, spiking temperatures are driving those levels back up and will play a major role in the methylmercury levels of marine life in the future.

The findings are published in the journal Nature.

“This research is a major advance in understanding how and why ocean predators, such as tuna and swordfish, are accumulating mercury,” said Elsie Sunderland, senior author of the paper.

“Being able to predict the future of mercury levels in fish has been difficult to answer because, until now, we didn’t have a good understanding of why methylmercury levels were so high in big fish,” said Amina Schartup, first author of the paper.

Based on the new model, the researchers predict that an increase of 1 degree Celsius in seawater temperature, relative to the year 2000, would lead to a 32% increase in methylmercury levels in cod and a 70% increase in spiny dogfish.

“This study brings together different kinds of data with models in a way that will have a direct impact on how we manage fisheries,” says Hedy Edmonds, a program director in NSF’s Division of Ocean Sciences, which funded the research.

—  NSF Public Affairs, (703) 292-8070 media@nsf.gov

Source

Climate change conversations can be difficult for both skeptics, environmentalists

Having productive conversations about climate change isn’t only challenging when dealing with skeptics, it can also be difficult for environmentalists, according to two studies presented at the annual convention of the American Psychological Association.

The first of the studies found that reinforcing belief and trust in science may be a strategy to help shift the views of climate change skeptics and make them more open to the facts being presented by the other side.

“Within the United States, bipartisan progress on climate change has essentially come to a standstill because many conservatives doubt the findings of climate science and many liberals cannot fathom that any rational human can doubt the scientific consensus on the issue,” said Carly D. Robinson, MEd, of Harvard University, who presented the research. “These opposing perspectives do not create a starting point for productive conversations to help our country address climate change. Our goal was to find an intervention that might change the current situation.”

Though previous research has shown that social pressure to disbelieve in climate change stems from the political right and that conservatives’ trust in science has eroded, Robinson and her colleagues theorized that most people would find at least some branches of science credible. Leveraging those beliefs could lead climate skeptics to shift their views, they said.

“When people are faced with two or more opposing beliefs, ideas and values, it tends to create discomfort, which can lead people to becoming more open-minded about a particular issue,” said Christine Vriesema, PhD, of the University of California, Santa Barbara and a co-author of the study.

The researchers surveyed nearly 700 participants from the U.S. Half were given surveys about their belief in science (e.g., “How credible is the medical data that germs are a primary cause of disease?” and “How certain are you that physicists’ theory of gravity accurately explains why objects fall when dropped?”) and their belief in climate science (e.g., “How credible is the climate science data that ocean temperatures are rising?” and “How certain are you that global warming explains many of the new weather patterns we are seeing today?”). The other half was only surveyed about their belief in climate science. All participants reported if they considered themselves politically liberal, moderate or conservative.

“As we predicted in our pre-registration, conservatives reported a greater belief in climate science if they were asked questions first about their belief in other areas of science,” said Robinson. “For climate skeptics, it likely became awkward to report on our survey that they believed in science while at the same time, denying the findings of climate science. That dissonance led many to adjust their beliefs to show greater support for the existence of climate change.”

The findings showed that beliefs in climate science are malleable and not fixed, said Robinson.

“We were pleasantly surprised that a brief, two-minute survey changed skeptics’ views on climate change,” said Robinson. “It is exciting to know that in real-world settings, we might be able to have more productive climate conversations by starting from a place of common belief.”

The second study showed that igniting a sense of resilience and perseverance can increase action and engagement around climate change for people who work in aquariums, national parks and zoos.

“Many educators working at these institutions reported wanting to talk about climate change and visitors reported wanting to hear about it, yet many educators still felt uncomfortable bringing the topic into their conversations because they were worried about being able to communicate effectively,” said Nathaniel Geiger, PhD, of Indiana University who presented the research.

The study included 203 science educators from zoos, aquariums and national parks who were part of a yearlong communication training program from the National Network of Ocean and Climate Change Interpretation designed to build participants’ confidence in talking about climate change. The training consisted of study groups, group assignments, readings, discussions and weekend retreats. During the last six months of the program, participants worked to integrate what they had learned into their jobs.

Survey data were collected one month before and one month after the training program and again six to nine months later.

Geiger and his colleagues examined two components of hopeful thinking to see which one might lead to the success of the training program: agency (e.g., enthusiasm, a sense of determination) and pathways (e.g., resilience and perseverance strategies) and how those influenced participants’ reports of engagement about climate change.

Participants rated their “agency thinking” (e.g., “I energetically do all I can do to discuss climate change” and “I anticipate that efforts to discuss climate change will be pretty successful”) and their “pathways thinking” (e.g., “I can think of many ways to discuss climate change”) in each survey. The science educators also reported the frequency with which they discussed climate change with the general public and visitors to their institutions, ranging from never to daily.

Geiger and his team found that pathways thinking was more successful at inspiring conversations about climate change than agency.

“Our findings suggested that portions of the training that taught how to persevere and be resilient in the face of difficult climate change conversations may have been the most effective at promoting discussion,” Geiger said.

The training program also increased the frequency with which the science educators spoke about climate change with visitors, from less than once per month prior to the training to more than two or three times per month afterward, he said.

“We found it uplifting that the training program showed such a robust effect at promoting these difficult discussions,” said Geiger. “We believe that climate change advocates and educators will find this work helpful toward meeting their goal of crafting more effective training programs to boost climate change engagement.”

Source

Research Headlines – Reactor design to make nuclear waste less radioactive

Related theme(s) and subtheme(s)

Countries involved in the project described in the article
 |   |   |   |   |   |   |   | 

Add to PDF “basket”

High-level nuclear waste includes long-lived and high-radiotoxic radionuclides. An EU-funded project helps to solve this issue by carrying out the research needed to build a facility that is capable of splitting material with long radioactive half-lives into radionuclide products with 1 000 times shorter half-lives.

Image

© Vlad #193947515, source: stock.adobe.com 2019

High-level nuclear waste remains hazardous for very long periods. Could it be made safer before being buried underground? Work by SCK•CEN and its international partners is aiming to do just that, in support of the realisation of the MYRRHA research facility in Belgium.

Here, a reactor is going to be built not to generate electricity but to dramatically reduce the radiotoxicity of high-level nuclear waste from spent fuel via nuclear transmutation.

The EU-funded MYRTE project is carrying out research towards demonstrating the feasibility of transmuting high-level waste at industrial scale. The idea is that radiotoxic atoms with long half-lives are each split into two much less hazardous products with strongly reduced (by 1 000 times) half-lives, in a novel reactor system using nuclear fission.

‘If there were technical means to reduce radiotoxicity from hundreds of thousands of years to some hundreds of years, that would be a major breakthrough for the public accepting a solution to the nuclear waste challenge,’ says project coordinator Peter Baeten of the SCK•CEN Belgian Nuclear Research Centre. ‘It would be more manageable compared to a human life timescale.’

The waste would still need deep underground storage, but the high-radiotoxic radionuclides products would not last as long, the heat load would be easier to manage and the footprint of the underground disposal site would be reduced.

Technological demonstration

To achieve its goal, the demonstration MYRRHA research facility needs to have a combination of innovative elements. MYRTE is helping to realise these through work packages focusing on the accelerator, thermal hydraulics, chemistry, reactor physics and fuel.

MYRRHA is an accelerator-driven system, comprising a proton accelerator coupled to a sub-critical reactor. The reactor therefore only works when the accelerator injects protons into it. MYRTE has made advances in the design of the accelerator and the safety demonstration of the reactor concept.

‘One of the main challenges is optimising the reliability of the accelerator,’ says Baeten. The project is constructing the first part of this unique accelerator. ‘This has also had an impact on the accelerator community, as now they see, thanks to this project, that major steps can be made in improving reliability. This is an important spin-off and valorisation of the project.’

Thermal hydraulics studies are providing a better understanding of the behaviour of the special coolant, liquid lead-bismuth, inside the reactor. The chemistry work package has taken major strides in completing the studies required by the safety authorities for assessing the behaviour of radioactive elements produced in the reactor.

The behaviour of neutrons, the sub-atomic particle flying around the sub-critical core, is studied in a 100-watt reactor. They behave the same way as they do in a 100-megawatt reactor. ‘We have built a special research facility to study them, we call it mini-MYRRHA,’ says Baeten.

The final work package concerns dedicated transmutation fuel. Specific elements, called minor actinides, must be removed from the spent fuel from nuclear power plants, then converted into fuel targets to put in the accelerator-driven system.

‘The advantage of doing transmutation in an accelerator-driven system is that you can do it in a concentrated way,’ says Baeten. ‘It means you can put between 40 and 50 % of the high-level waste into your reactor core. Without this accelerator and a sub-critical system, you can only put in around 2-3 % in reactors intended for electricity production.’

International collaboration

Whether or not EU countries will continue to use nuclear for electricity production, governments are still confronted with the challenge of high-level nuclear waste. It is an issue for every country that has or once had a nuclear power programme.

‘The big advantage of this European project is that you can call on the excellence of European partners. This is a big added value, because here in Europe we have several centres of excellence in different technical domains,’ Baeten says.

For example, he notes the strong collaboration between French and German partners in building the accelerator, and the role of Swiss expertise in the chemistry work package.

Project details

  • Project acronym: MYRTE
  • Participants: Belgium (Coordinator), France, Spain, Switzerland, Italy, Germany, Netherlands, Slovenia, Portugal
  • Project N°: 662186
  • Total costs: € 11 994 610
  • EU contribution: € 8 995 962
  • Duration: April 2015 to September 2019

See also

Search articles

Notes:
To restrict search results to articles in the Information Centre, i.e. this site, use this search box rather than the one at the top of the page.

After searching, you can expand the results to include the whole Research and Innovation web site, or another section of it, or all Europa, afterwards without searching again.

Please note that new content may take a few days to be indexed by the search engine and therefore to appear in the results.

Source

MIT and Harvard join forces to address early childhood literacy

Today, MIT’s Integrated Learning Initiative (MITili), Harvard Graduate School of Education (HGSE), and Florida State University (FSU) announced a collaboration to make sure every child learns to read well enough by the end of third grade to make learning more effective later in their education. This will be achieved through research on how personalized learning and intervention improve early childhood literacy.

Research shows that students who fail to read adequately in first grade have a 90 percent probability of reading poorly in fourth grade, and a 75 percent probability of reading poorly in high school. This compounds the need to level the playing field in literacy early in a child’s education.

This new collaboration, called Reach Every Reader, brings MITili, HGSE, and Florida State University researchers together to work on rigorous scientific approaches to personalized learning for literacy, to develop diagnostic tools and interventions to help young children at risk for literacy before they fail, and to build capacity among educators, caregivers, and policy makers to advance ongoing conversations and instructional strategies around personalized learning.  The initiative is supported by a $30 million grant from Priscilla Chan and Mark Zuckerberg, co-founders of the Chan Zuckerberg Initiative.

“For a young child, struggling to read can be a crushing blow with lifelong consequences. Multiply that experience by millions of children, and it’s a crisis for our society,” says MIT President L. Rafael Reif. “At MIT, we approach the problem as scientists and engineers: by seeking to understand the brain science of how learning happens, and by building innovative technologies and solutions to help. We are delighted to be able to contribute in these ways to the exciting collaboration behind Reach Every Reader.”

“We are excited to support the launch of Reach Every Reader, a unique combination of cutting-edge education and neuroscience research to better understand how we can help every kid stay on track to reading on grade level by the end of third grade. I know from my work at The Primary School how important it is to identify learning barriers students face early and provide them with the right supports to succeed,” says Chan, who is also the founder and CEO of The Primary School. “This new program represents the type of bold, innovative thinking that we believe will help build a future for everyone and enable transformative learning experiences.”

“This new collaboration between MITili and HGSE synergizes MIT’s strengths in science and engineering with HGSE’s expertise in the education of children. In addition, working with researchers in the Florida Center for Reading Research and College of Communication and Information at FSU will help us gain expertise in early literacy screening and assessment. We need all this knowledge to improve education, especially for children most vulnerable to falling behind,” says John Gabrieli, the Grover Hermann Professor of Health Sciences and Technology, a professor in brain and cognitive sciences, and director of MITili.

Gabrieli and his collaborators are developing a web-based tool for the early identification of reading challenges to help direct children immediately toward personalized interventions. This work builds on Gabrieli’s research on the neural and cognitive development of learning in children, and the ways neuroscience can inform and advance educational outcomes. A key component of Reach Every Reader is to examine the interventions that work for which student, building substantive research in this emerging field. The team will work with school partners to deliver these interventions to kindergarten students in summer programs and, longer term, implement these tools into the school curriculum.

“Nothing is more fundamental to all aspects of education and citizenship than the power to read,” Gabrieli explains. “This collaboration is inspired by the mission of trying to have every child, regardless of circumstance, learn to read well enough by third grade so that every child can read to learn throughout the schooling and workplace years.”

Reach Every Reader is part of MITili’s larger vision to advance multidisciplinary research on the science of learning that will inform and strengthen approaches to preK-12 education. “Science is continuously shedding more light on how we learn, and how we ought to teach,” says Sanjay Sarma, vice president for Open Learning at MIT. “MITili and HGSE are addressing early childhood literacy head-on through this collaboration.”

The initiative is funded by Chan and Zuckerberg, who founded the Chan Zuckerberg Initiative (CZI) together in 2015. The philanthropic organization supports a range of educational research initiatives, focusing on four key milestones: kindergarten readiness, third-grade literacy and math, high school transitions, and postsecondary success.


Topics: Office of Open Learning, MITili, Brain and cognitive sciences, School of Science, K-12 education, education, Education, teaching, academics, Office of Digital Learning, Learning, Language

Source

A single-photon source you can make at home

Quantum computing and quantum cryptography are expected to give much higher capabilities than their classical counterparts. For example, the computation power in a quantum system may grow at a double exponential rate instead of a classical linear rate due to the different nature of the basic unit, the qubit (quantum bit). Entangled particles enable the unbreakable codes for secure communications. The importance of these technologies motivated the U.S. government to legislate the National Quantum Initiative Act, which authorizes $1.2 billion over the following five years for developing quantum information science.

Single photons can be an essential qubit source for these applications. To achieve practical usage, the single photons should be in the telecom wavelengths, which range from 1,260-1,675 nanometers, and the device should be functional at room temperature. To date, only a single fluorescent quantum defect in carbon nanotubes possesses both features simultaneously. However, the precise creation of these single defects has been hampered by preparation methods that require special reactants, are difficult to control, proceed slowly, generate non-emissive defects, or are challenging to scale.

Now, research from Angela Belcher, head of the MIT Department of Biologicial Engineering, Koch Institute member, and the James Crafts Professor of Biological Engineering, and postdoc Ching-Wei Lin, published online in Nature Communications, describes a simple solution to create carbon-nanotube based single-photon emitters, which are known as fluorescent quantum defects.

“We can now quickly synthesize these fluorescent quantum defects within a minute, simply using household bleach and light,” Lin says. “And we can produce them at large scale easily.”

Belcher’s lab has demonstrated this amazingly simple method with minimum non-fluorescent defects generated. Carbon nanotubes were submerged in bleach and then irradiated with ultraviolet light for less than a minute to create the fluorescent quantum defects.

The availability of fluorescent quantum defects from this method has greatly reduced the barrier for translating fundamental studies to practical applications. Meanwhile, the nanotubes become even brighter after the creation of these fluorescent defects. In addition, the excitation/emission of these defect carbon nanotubes is shifted to the so-called shortwave infrared region (900-1,600 nm), which is an invisible optical window that has slightly longer wavelengths than the regular near-infrared. What’s more, operations at longer wavelengths with brighter defect emitters allow researchers to see through the tissue more clearly and deeply for optical imaging. As a result, the defect carbon nanotube-based optical probes (usually to conjugate the targeting materials to these defect carbon nanotubes) will greatly improve the imaging performance, enabling cancer detection and treatments such as early detection and image-guided surgery.

Cancers were the second-leading cause of death in the United States in 2017. Extrapolated, this comes out to around 500,000 people who die from cancer every year. The goal in the Belcher Lab is to develop very bright probes that work at the optimal optical window for looking at very small tumors, primarily on ovarian and brain cancers. If doctors can detect the disease earlier, the survival rate can be significantly increased, according to statistics. And now the new bright fluorescent quantum defect can be the right tool to upgrade the current imaging systems, looking at even smaller tumors through the defect emission.

“We have demonstrated a clear visualization of vasculature structure and lymphatic systems using 150 times less amount of probes compared to previous generation of imaging systems,” Belcher says, “This indicates that we have moved a step forward closer to cancer early detection.”

In collaboration with contributors from Rice University, reearchers can identify for the first time the distribution of quantum defects in carbon nanotubes using a novel spectroscopy method called variance spectroscopy. This method helped the researchers monitor the quality of the quantum defect contained-carbon nanotubes and find the correct synthetic parameters easier.

Other co-authors at MIT include biological engineering graduate student Uyanga Tsedev, materials science and engineering graduate student Shengnan Huang, as well as Professor R. Bruce Weisman, Sergei Bachilo, and Zheng Yu of Rice University.

This work was supported by grants from the Marble Center for Cancer Nanomedicine, the Koch Institute Frontier Research Program, Frontier, the National Science Foundation, and the Welch Foundation.


Source

Where to fish? In times of uncertainty, experienced fishing boat captains may fare better

Research News

Where to fish? In times of uncertainty, experienced fishing boat captains may fare better

Study of 540,000 fishing vessel records shows exploration is beneficial in face of uncertainty

fishing boat

Exploration of new fishing sites benefits boat captains in times of uncertainty.

August 7, 2019

When making choices, people tend to go with what they know, or try something new. We make these trade-offs every day. Does one strategy have an advantage over another? Scientists decided to research this question by looking at fishing boat captains, who face this choice again and again when deciding where to fish.

To find out which strategy leads to greater success, scientists at the University of California, Davis, and their colleagues looked at 540,000 fishing vessel position records from nearly 2,500 commercial fishing trips in the U.S. Gulf of Mexico, along with their revenues. The results are published in the journal Nature Communications.

“It looks like exploration pays off in the face of uncertainty,” said co-lead author Shay O’Farrell of UC Davis. “This is particularly important in the context of global environmental change, when disturbances such as storms and droughts are predicted to increase.”

The study found that some vessels consistently explore new territory and invest more time and resources into sampling new places to fish. In times of stability, exploratory vessels performed no better or worse on average than vessels that stuck with consistency.

“In relatively stable environments, we would expect that any gains from switching behaviors would usually go away, otherwise vessels would be changing how they fish,” co-author James Sanchirico of UC Davis said.

When boats were suddenly forced to fish elsewhere during a 2009 closure of popular fishing grounds in the Gulf, those with a history of exploration experienced significantly fewer impacts from the disruption. That may be because boat captains could draw on their experience to select new fishing grounds.

“This study illustrates how complex human behavior during times of stability can influence fishing pressure in times of change,” says Mike Sieracki, a program director in NSF’s Division of Ocean Sciences, which funded the research.

—  NSF Public Affairs, (703) 292-8070 media@nsf.gov

Source