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  • richardmitnick 11:04 am on September 15, 2019 Permalink | Reply
    Tags: "This device harnesses the cold night sky to generate electricity in the dark", , , Stanford University   

    From Stanford University via Science News: “This device harnesses the cold night sky to generate electricity in the dark” 

    Stanford University Name
    From Stanford University

    via

    Science News

    September 12, 2019
    Maria Temming

    A prototype powered a small light-emitting diode in a trial run.

    1
    A new device that harvests energy from the cold night sky could one day light up rooms, charge phones and power devices for people off the grid. Credit Ryan Hutton/Unsplash

    A new device is an anti-solar panel, harvesting energy from the cold night sky.

    By harnessing the temperature difference between Earth and outer space, a prototype of the device produced enough electricity at night to power a small LED light. A bigger version of this nighttime generator could someday light rooms, charge phones or power other electronics in remote or low-resource areas that lack electricity at night when solar panels don’t work, researchers report online September 12 in Joule.

    The core of the new night-light is a thermoelectric generator, which produces electricity when one side of the generator is cooler than the other (SN: 6/1/18). The sky-facing side of the generator is attached to an aluminum plate sealed beneath a transparent cover and surrounded with insulation to keep heat out. This plate stays cooler than the ambient air by shedding any heat it absorbs as infrared radiation (SN: 9/28/18). That radiation can zip up through the transparent cover and the atmosphere toward the cold sink of outer space.

    Meanwhile, the bottom of the generator is attached to an exposed aluminum plate that is continually warmed by ambient air. At night, when not baking under the sun, the top plate can get a couple of degrees Celsius cooler than the bottom of the generator.

    Engineer Wei Li of Stanford University and colleagues tested a 20-centimeter prototype of the device on a clear December night in Stanford, Calif. The generator produced up to about 25 milliwatts of power per square meter of device — enough to light a small light-emitting diode, or LED bulb. The team estimates that further design improvements, like better insulation around the cool top plate, could boost production up to at least 0.5 watts per square meter.

    3
    A device that uses the night sky to generate electricity (pictured) powered a small LED bulb in one rooftop experiment. Credit Wei Li

    “It’s a very clever idea,” says Yuan Yang, a materials scientist at Columbia University not involved in the work. “The power generation is much less than solar panels,” which generally produce at least 100 watts per square meter. But this nighttime generator may be useful for emergency backup power, or energy for people living off the grid, Yang says.

    A typical lamp bulb might consume a few watts of electricity, says Shanhui Fan, an electrical engineer at Stanford University who worked on the device. So a device that took up a few square meters of roof space could light up a room with energy from the night sky.

    Aaswath Raman, a materials scientist and engineer at UCLA, also envisions using their team’s generator to help power remote weather stations or other environmental sensors. This may be especially useful in polar regions that don’t see sunlight for months at a time, Raman says. “If you have some low-power load and you need to power it through three months of darkness, this might be a way.”

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 6:55 am on September 10, 2019 Permalink | Reply
    Tags: , , , Electrochemical conversion, , Stanford University   

    From SLAC National Accelerator Lab: “Plastics, fuels and chemical feedstocks from CO2? They’re working on it.” 

    From SLAC National Accelerator Lab

    September 9, 2019
    Glennda Chui

    1
    Researchers at Stanford and SLAC are working on ways to convert waste carbon dioxide (CO2) into chemical feedstocks and fuels, turning a potent greenhouse gas into valuable products. The process is called electrochemical conversion. When powered by renewable energy sources (far left), it could reduce levels of carbon dioxide in the air and store energy from these intermittent sources in a form that can be used any time. (Greg Stewart/SLAC National Accelerator Laboratory)

    One way to reduce the level of carbon dioxide in the atmosphere, which is now at its highest point in 800,000 years, would be to capture the potent greenhouse gas from the smokestacks of factories and power plants and use renewable energy to turn it into things we need, says Thomas Jaramillo.

    As director of SUNCAT Center for Interface Science and Catalysis, a joint institute of Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory, he’s in a position to help make that happen.

    A major focus of SUNCAT research is finding ways to transform CO2 into chemicals, fuels, and other products, from methanol to plastics, detergents and synthetic natural gas. The production of these chemicals and materials from fossil fuel ingredients now accounts for 10% of global carbon emissions; the production of gasoline, diesel, and jet fuel accounts for much, much more.

    “We have already emitted too much CO2, and we’re on track to continue emitting it for years, since 80% of the energy consumed worldwide today comes from fossil fuels,” says Stephanie Nitopi, whose SUNCAT research is the basis of her newly acquired Stanford PhD.

    “You could capture CO2 from smokestacks and store it underground,” she says. “That’s one technology currently in play. An alternative is to use it as a feedstock to make fuels, plastics, and specialty chemicals, which shifts the financial paradigm. Waste CO2 emissions now become something you can recycle into valuable products, providing a new incentive to reduce the amount of CO2 released into the atmosphere. That’s a win-win.”

    We asked Nitopi, Jaramillo, SUNCAT staff scientist Christopher Hahn and postdoctoral researcher Lei Wang to tell us what they’re working on and why it matters.

    Q. First the basics: How do you convert CO2 into these other products?

    Tom: It’s essentially a form of artificial photosynthesis, which is why DOE’s Joint Center for Artificial Photosynthesis funds our work. Plants use solar energy to convert CO2 from the air into carbon in their tissues. Similarly, we want to develop technologies that use renewable energy, like solar or wind, to convert CO2 from industrial emissions into carbon-based products.

    Chris: One way to do this is called electrochemical CO2 reduction, where you bubble CO2 gas up through water and it reacts with the water on the surface of a copper-based electrode. The copper acts as a catalyst, bringing the chemical ingredients together in a way that encourages them to react. Put very simply, the initial reaction strips an oxygen atom from CO2 to form carbon monoxide, or CO, which is an important industrial chemical in its own right. Then other electrochemical reactions turn CO into important molecules such as alcohols, fuels and other things.

    Today this process requires a copper-based catalyst. It’s the only one known to do the job. But these reactions can produce numerous products, and separating out the one you want is costly, so we need to identify new catalysts that are able to guide the reaction toward making only the desired product.

    How so?

    Lei: When it comes to improving a catalyst’s performance, one of the key things we look at is how to make them more selective, so they generate just one product and nothing else. About 90 percent of fuel and chemical manufacturing depends on catalysts, and getting rid of unwanted byproducts is a big part of the cost.

    We also look at how to make catalysts more efficient by increasing their surface area, so there are a lot more places in a given volume of material where reactions can occur simultaneously. This increases the production rate.

    Recently we discovered something surprising [Nature Catalysis]: When we increased the surface area of a copper-based catalyst by forming it into a flaky “nanoflower” shape, it made the reaction both more efficient and more selective. In fact, it produced virtually no byproduct hydrogen gas that we could measure. So this could offer a way to tune reactions to make them more selective and cost-competitive.

    Stephanie: This was so surprising that we decided to revisit all the research we could find [Chem. Rev.] on catalyzing electrochemical CO2 conversion with copper, and the many ways people have tried to understand and fine-tune the process, using both theory and experiments, going back four decades. There’s been an explosion of research on this – about 60 papers had been published as of 2006, versus more than 430 out there today – and analyzing all the studies with our collaborators at the Technical University of Denmark took two years.

    We were trying to figure out what makes copper special, why it’s the only catalyst that can make some of these interesting products, and how we can make it even more efficient and selective – what techniques have actually pushed the needle forward? We also offered our perspectives on promising research directions.

    One of our conclusions confirms the results of the earlier study: The copper catalyst’s surface area can be used to improve both the selectivity and overall efficiency of reactions. So this is well worth considering as a chemical production strategy.

    Does this approach have other benefits?

    Tom: Absolutely. If we use clean, renewable energy, like wind or solar, to power the controlled conversion of waste CO2 to a wide range of other products, this could actually draw down levels of CO2 in the atmosphere, which we will need to do to stave off the worst effects of global climate change.

    Chris: And when we use renewable energy to convert CO2 to fuels, we’re storing the variable energy from those renewables in a form that can be used any time. In addition, with the right catalyst, these reactions could take place at close to room temperature, instead of the high temperatures and pressures often needed today, making them much more energy efficient.

    How close are we to making it happen?

    Tom: Chris and I explored this question in a recent Perspective article in Science, written with researchers from the University of Toronto and TOTAL American Services, which is an oil and gas exploration and production services firm.

    We concluded that renewable energy prices would have to fall below 4 cents per kilowatt hour, and systems would need to convert incoming electricity to chemical products with at least 60% efficiency, to make the approach economically competitive with today’s methods.

    Chris: This switch couldn’t happen all at once; the chemical industry is too big and complex for that. So one approach would be to start with making high-value, high-volume products like ethylene, which is used to make alcohols, polyester, antifreeze, plastics and synthetic rubber. It’s a $230 billion global market today. Switching from fossil fuels to CO2 as a starting ingredient for ethylene in a process powered by renewables could potentially save the equivalent of about 860 million metric tons of CO2 emissions per year.

    The same step-by-step approach applies to sources of CO2. Industry could initially use relatively pure CO2 emissions from cement plants, breweries or distilleries, for instance, and this would have the side benefit of decentralizing manufacturing. Every country could provide for itself, develop the technology it needs, and give its people a better quality of life.

    Tom: Once you enter certain markets and start scaling up the technology, you can attack other products that are tougher to make competitively today. What this paper concludes is that these new processes have a chance to change the world.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    SLAC/LCLS


    SLAC/LCLS II projected view


    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.

     
  • richardmitnick 10:06 am on September 9, 2019 Permalink | Reply
    Tags: "When You Don’t Know You Feel Alone in the World", , , Stanford University, Undiagnosed Diseases Network   

    From Stanford University: “When You Don’t Know, You Feel Alone in the World” 

    Stanford University Name
    From Stanford University

    The odyssey of the undiagnosed.

    9.9.19

    By Deni Ellis Béchard
    Photography by Timothy Archibald

    1
    IT’S GENETIC: Carson’s cerebral palsy diagnosis had to be thrown out after his brother, Chase, began to show similar symptoms.

    Danny Miller was spending every free minute searching the internet, reading page after page about medical conditions. His son, Carson, was a year old, and Miller believed something was wrong with him. He and his wife, Nikki, had noticed the first signs a few months earlier, during playdates with other children. He couldn’t exactly put his finger on the problem. “It was just the quality of movement and the types of movement,” Miller recalls. “He didn’t like tummy time. The movements were a little bit stiff and not as smooth as the other kids’.”

    During an appointment with the pediatrician, the Millers were told that children develop at different rates. And yet Carson’s hands were curled tightly into fists, and his movements showed signs of spasticity. The Millers set up appointments with neurologists and behavior specialists, all of whom said there was probably nothing to worry about.

    “That’s when I sort of began to dive into my research career,” Miller says. “I was looking at different conditions and would just enter symptoms into Google to figure out what would come up or what would explain why he wasn’t crawling, why he wasn’t pulling himself up to standing.”

    The condition that Miller repeatedly circled back to was cerebral palsy. Its symptoms matched Carson’s: tremors, muscle weakness and lack of coordination. The cause was often unknown and usually attributed to atypical brain development or damage during pregnancy or childbirth, or shortly afterward. Miller continued taking Carson to see specialists, and Carson finally received a diagnosis of cerebral palsy in 2013, when he was 15 months old.

    Shortly afterward, the Millers had their second son, Chase. The pregnancy was easy, and the baby looked healthy. “But fast forward to 6, 7 months of age,” Miller says, “[and] we began to see some of the same things. That’s when we really began to get worried.”

    Suddenly, the cerebral palsy diagnosis seemed unlikely. CP occurs in approximately 2 out of 1,000 births and in 1 out of 1,000 that are not premature. The odds of both boys having it were 1 in a million. Miller turned his research toward genetic movement disorders. Testing for the boys was now more extensive: metabolomics (the study of the body’s metabolic byproducts, such as lactic acid or nitrogen compounds), karyotyping (the evaluation of the chromosomes for structural abnormalities), gene panels (to test for common mutations) and then sequencing of the entire exome (the genome’s coding portions, which are expressed in proteins and linked to traits). The brothers also received several MRIs. Carson’s showed lesions in the brain’s basal ganglia, an area important for motor activity. But the neurologist couldn’t identify the cause. Many disorders—among them many rare diseases—could cause lesions.

    As the Millers did test after test for their sons, the boys’ physical development plateaued. By the time Carson was 5 and Chase was 3, neither could speak or walk, and their motor control was extremely limited, and yet both boys appeared to be cognitively intact and could understand spoken language. Though Miller continued researching diseases online, none of the symptoms quite fit.

    In 2016, Miller read about the Undiagnosed Diseases Network, a research initiative created by the National Institutes of Health in 2014 in conjunction with six clinical sites at academic medical centers, including Stanford. The UDN accepted its first patients—adults as well as children—in September 2015. In its first 20 months, it would evaluate 601 patients, find diagnoses for 35 percent of them and identify 31 previously unknown syndromes. In 2019, it expanded to include a dozen clinical sites, and it has now accepted 1,393 patients, evaluated 1,190 of them and made 330 diagnoses. The network works collaboratively, sharing data and resources and bringing together the best specialists from multiple institutions to take on the most challenging medical cases. It refuses no one on the basis of ability to pay. The only standard is whether the person has, according to the website, a condition that includes at least one objective medical finding—a detectable biological anomaly—and “that remains undiagnosed despite thorough evaluation.”

    For the Millers, the UDN was a lifeline after a long, repetitive and frustrating search.

    “It was sort of the end of the line for undiagnosed families,” Miller recalls. He spent the next several months compiling his sons’ medical records. In the spring of 2016, he applied on their behalf to the UDN. By December, they were admitted, and since they lived in Corte Madera, Calif., a 30-minute drive north of San Francisco, they were assigned to Stanford’s Center for Undiagnosed Diseases.

    “It was very scary,” Miller says, recalling the stress of four years of searching for answers and coming up empty. “As a parent, you go through a lot of self-doubt, a lot of blame. You wonder, ‘What did we do wrong? Did I not take care of my body the right way as a young man and now that’s had an impact on our children?’ My wife went through a period where she asked, what did she do wrong during her pregnancy? Did she not get proper nutrition? We were both really determined to try to find answers, and we weren’t getting them.”

    The Millers’ first visit to Stanford was in early 2017. Again, they went through a series of consultations with specialists. The team then decided to do whole-genome sequencing for the family—the parents as well
    as Carson and Chase.

    A little more than a year later, the Millers had an answer.

    The head of pediatrics at Stanford’s Center for Undiagnosed Diseases is associate professor Jon Bernstein, MD ’03, PhD ’03, a pediatric medical geneticist who chose his field of study because it combined the kind of challenging problem solving he found satisfying with a lifelong love of working with children.

    After he joined Stanford Medicine’s faculty in 2008, much of his focus was on helping families find explanations for their children’s chronic conditions. When he heard that several colleagues were applying to join the UDN, he wrote to say he wanted to be involved.

    Through the UDN, Bernstein has access to far more diagnostic tools—and more freedom to use them—than he has in a standard clinic, where patients are generally limited to services included in their health plans. Whereas research scientists use techniques under development—such as whole-genome sequencing and RNA sequencing—few clinicians have access to those services and few health plans cover them until the techniques become sufficiently mainstream that their costs decrease.

    When the Millers brought Chase and Carson, Bernstein and the UDN team compared their symptoms with those of known conditions shared in databases among scientists around the world. Whole-genome sequencing was the next step. Exome sequencing shows only the expressed genes—1.5 percent of the genome—whereas whole-genome sequencing covers the regions that control many other processes, including which genes get expressed.

    When the results came back, they showed two mutations that might have an impact—one in the father and one in the mother, both of which the sons had inherited. A paper published in 2016 in the American Journal of Human Genetics had described the mother’s mutation for the first time, introducing MEPAN syndrome (an acronym for mitochondrial enoyl CoA reductase protein-associated neurodegeneration). The symptoms matched those of the brothers, from the inability to speak and movement difficulties to the lesions in the basal ganglia. The mutation hadn’t come up in the boys’ previous exome sequencing possibly because it was discovered so recently and was unlikely to be included in all databases, or because it lay at the boundary of an exon and an intron—DNA that is expressed and that is not.

    The father’s mutation, however, was entirely in the unexpressed (or noncoding) regions of DNA, which explained why it hadn’t shown up during exome sequencing. Though his mutation had never been described in the scientific literature, it lay within a region that was predicted to regulate the same gene affected by the mother’s mutation: the MECR gene, which is involved in producing mitochondrial fatty acids in humans.

    In both Carson and Chase, the MECR gene from their mother didn’t function. The Stanford team established that the MECR gene from their father—though intact—wasn’t expressed. Since each parent carried one functioning copy of the gene, neither of them had MEPAN. There was a 50 percent chance that each parent would pass on his or her single mutation, and a 25 percent chance that a child would receive the mutations from both parents. Carson and Chase, despite the odds, had each received the two mutations. The result was that mitochondria—the parts of cells that produce energy—functioned poorly.

    For the Millers, the boys’ symptoms suddenly made sense. The brain, though it constitutes only 2 percent of the body’s weight, uses approximately 20 percent of its energy. And the basal ganglia—because it controls motor functions—is one of its most energy-intensive regions. Since Carson and Chase had a genetic mitochondrial disease, this area was most affected, resulting in severe impairment of movement.

    Through the UDN, the Millers were put in contact with other families with MEPAN.

    “With rare diseases,” Miller says, “building community is really important—connecting with the other families.”

    He acknowledges how scary it was to find out that their sons have a rare genetic condition with no proven treatments, but he was relieved to know what they faced. “It allowed us to turn the page and write the next chapter: connect with other MEPAN families, figure out who the researchers are that can help discover treatments.”

    2

    Though only seven patients had been identified worldwide, the families were able to compare notes on potential treatments and how the disease might progress. The oldest known patient, Mike Cohn, lived in Minnesota. He had gone decades without a diagnosis and was an exemplar of how a person could embrace life with a disability. He was 50, had a master’s in education and ran not only a nonprofit to create awareness around disabilities but also his own dance company.

    Carson is almost 9 and Chase is 6, and both lead active lives. “Even though they can’t talk, they’re very vocal in the morning,” Miller says. “They just make noises and let us know that they’re up.”

    Neither of them can crawl, but Chase can climb out of bed and roll down the hallway to the kitchen, whereas Carson can roll only a little. Their parents bathe them, feed them and take them to school, where each has a one-on-one aide who serves as their hands and voice. Miller remarks that the boys are often joking and almost always smiling, though once, a few months ago, with a speech therapist, Carson wrote, “I hate my wheelchair.”

    To communicate, the boys use assistive technology: an iPad for Chase and a speech-generating device with an eye tracker for Carson, whose motor skills were further limited after a brain infection. They have tried VR headsets and like watching YouTube videos of people playing Minecraft or Grand Theft Auto. Chase enjoys exploring the outdoors with his father and roughhousing, whereas Carson would often prefer to be inside reading or watching TV. Carson has also become fascinated by the science of how the body works and watches videos about everything from digestion to reproduction. And he loves Harry Potter.

    “At the very end of the night, as he’s falling asleep,” Miller says, “I read him Harry Potter. We’re reading Harry Potter and the Order of the Phoenix right now, and we’re on like page 690. It’s supposed to be when he’s winding down, and as you’re reading the part where Harry is about to do battle with Voldemort, he gets very excited and animated.”

    Euan Ashley is one of the four principal investigators at Stanford’s Center for Undiagnosed Diseases and served as the first national co-chair of the UDN. Originally from Scotland, Ashley studied physiology and medicine at the University of Glasgow before earning a PhD in genetics from Oxford. He came to Stanford in 2002 as a cardiology fellow, joined the faculty in 2006, and is now a professor of medicine, of genetics and of biomedical data science. As he increasingly focused on precision medicine—which typically involves treating patients according to the genetics of their disease—he heard about the UDN. The National Institutes of Health had started the first center in Bethesda, Md., and, after its initial success, was partnering with academic medical centers. Ashley liked the idea of treating everyone regardless of their ability to pay, and he saw the central role of genetics in diagnostics. He applied alongside the Stanford scientists who would become the other principal investigators at the Center for Undiagnosed Diseases: Bernstein; Paul Fisher, ’84, a professor and pediatric neurologist; and Matthew Wheeler, an assistant professor and fellow cardiologist.

    A 2018 study conducted by UDN-affiliated researchers and published in the New England Journal of Medicine confirmed the power of the UDN model to shorten a patient’s diagnostic odyssey. Prior to being accepted by the UDN, in a small group of patients for whom data was available, the cumulative cost of health care was, on average, $305,428. A UDN evaluation leading to diagnosis averaged $18,903.

    Ashley attributes the UDN’s efficiency in part to its frequent practice of performing immediate exome or whole-genome sequencing, which can identify a syndrome and obviate visits to a merry-go-round of specialists, who may repeat expensive tests or MRIs. “These patients often go and get the same tests in a new place,” Ashley says. “One of the reasons I think the network is so successful is because it’s much more integrated than our normal health-care system. The key part of the approach for the UDN is that we integrate all the opinions and then find the right person who has seen something like this before.”

    The story of Lauren Wong illustrates how long the quest for an answer can be and how quickly it can be resolved. She and her fraternal twin, Nathanial, were born prematurely in 2015. Whereas Nathanial spent a day in the newborn intensive care unit, Lauren, who was much smaller, remained for more than two weeks. Afterward, as the twins grew up, their parents, Mary and Craig Wong, noticed that Lauren wasn’t developing as quickly. A neurologist diagnosed cerebral palsy, but as the months passed, more and more problems presented themselves. Lauren had little appetite. She developed infantile spasms, resulting in numerous, barely perceptible seizures each day. By the time she was 4, she was cognitively at the level of a 5-month-old and physically at the level of an 8-month-old. Eventually, the family’s neurologist ruled out CP and other known conditions. He requested exome sequencing several times, but the Wongs’ health insurance refused the cost.

    3
    COMMUNITY: About 50 children, most of them girls, have the same mutation as Lauren. Her family can now turn to others for advice.

    “When you don’t know,” Mary Wong says of the family’s search for a diagnosis as she tries not to cry, “you feel alone in the world. And you’re just uncertain of what to do next.”

    Every two hours, Lauren is fed via a tube in her stomach, since she doesn’t eat on her own. She receives physical and occupational therapy, as well as vision and speech services. During the day, Lauren attends a special class with a one-to-one aide to support her.

    “She’s a really good kid,” Mary says. “She’s always smiling. She’s never unhappy, which is crazy. Any little thing will make her smile, whether it be a toy or something that lights up or her brother walking by.”

    In 2017, Lauren was accepted at the UDN. Craig, Mary, Nathanial and Lauren all had their exomes sequenced. Within a month, the team at the Stanford center found that, unlike the other members of her family, Lauren had a defective copy of a gene called ALG13. This type of mutation was known as de novo—newly created in the embryo from an error during gene replication. The Stanford team informed them that roughly 20 other girls were known to have Lauren’s mutation and symptoms.

    “We were like, ‘Excuse me? Did you just say about 20?’” Mary recalls.

    In fact, the Wongs have learned, 40 to 50 children have the mutation, most of them girls. (Boys with a defective ALG13 are thought to often die before birth.) The oldest girl with the condition was 16. In many of them, the condition was expressed differently. Some were like Lauren. Others were more active. One was able to walk and run.

    “You just don’t know what to do for your child,” Mary says. “When that unknown is there, it’s hard to figure out which way to go. Even with the diagnosis, we’re still not sure where this is going to take us. But at least we have a group of people that have the same diagnosis, and we can go to them for advice.”

    One of Stanford’s first UDN patients, Anahi Villanueva, had a condition that was unknown to science. Shortly after Anahi’s birth in August 2008, her mother, Maria, saw that her daughter was just sleeping—“She didn’t even cry.” The doctors soon realized that Anahi had gone into a coma. She was transferred first to a hospital in Oakland and then, as her condition worsened, to Lucile Packard Children’s Hospital Stanford. Blood tests showed very low pH from high levels of lactic acid and ammonia.

    4
    RARE: Scientists had never before seen Anahi’s condition­, a mitochondrial disorder that affects energy production.

    “That’s the adult human equivalent of having run a marathon,” says Wheeler, the medical director for adults at the Stanford Center for Undiagnosed Diseases. “You get that sort of burning soreness that’s from lactic acid. It could lead to risk of arrhythmia, injury to the brain or death.”

    For days, Anahi received IV fluids until the acidemia subsided and she recovered. In the years that followed, she had similar crises, brought on by overexertion, not eating enough or—most commonly—a virus like the flu. Each time, her blood levels suggested that her body was exerting itself far beyond the norm. “A couple of times when she got really sick,” her mother recalls, “we thought she wouldn’t make it.”

    Though the episodes were caught early and addressed with emergency room visits and IV fluids, the doctors could offer no diagnosis, and yet the symptoms clearly suggested a mitochondrial disorder.

    One of the hallmarks of mitochondrial disorders is lactic acid buildup. When people can’t generate enough energy from the mitochondria, they produce lactic acid through fermentation—a more rapid but less efficient metabolic process. Anahi’s acidemia suggested that she was relying largely on this backup mechanism. Unlike Carson and Chase’s mitochondrial condition, hers allowed her to walk and speak so long as she avoided taxing activities and getting sick.

    When the UDN began accepting patients in 2015, Anahi was 6 years old. She had an MRI, exome sequencing and sequencing of the mitochondrial genome (mitochondria, being descended from bacteria that were incorporated into larger bacteria between 1.7 billion and
    2 billion years ago, have their own set of genes).

    The Stanford UDN team identified a mutation in a gene involved in the creation of ATP synthase, the mitochondrial subunit that makes adenosine triphosphate—or ATP—the molecule responsible for all energy in the human body (people generate their body weight in ATP every day). But the mutation was entirely new, existing nowhere in the scientific literature.

    “It looked like it was in both copies from her mom and her dad,” Bernstein recalls.

    The researchers searched through databases for another patient with a similar mutation, but nothing turned up. Fortuitously, when Wheeler presented Anahi’s case at a meeting of the American Society of Human Genetics, British scientist Robert Taylor—a specialist in mitochondrial diseases—said he had been studying a patient with similar symptoms and a similar but not identical mutation in the same gene.

    The next step involved creating a model organism—in this case, the fruit fly—to study the impact of the genes. First studied by the geneticist Thomas Hunt Morgan in the early 1900s, fruit flies are among the organisms that—thanks to their rapid breeding time and the facility with which they can be handled—have most furthered our current understanding of genetics.

    When a team of UDN researchers at Baylor knocked down the gene—reducing its expression—in fruit flies, no viable flies were born. A partial knockdown of the gene followed, with the researchers reducing expression only in the head. “When you do that,” Wheeler explains, “you get a shrunken-head fly, with a tiny head that’s very slow to develop.” The team then introduced Anahi’s mutation into a fly’s head, which developed with slight problems, confirming that Anahi’s version of the gene was impaired but still functional.

    Anahi was 9 when the scientists at the UDN made the diagnosis of the new mitochondrial disorder. Though she is not as tall as expected for her age and has to manage her effort carefully, she can otherwise live a relatively normal life.

    “She has missed so many days when she’s sick through the years,” Villanueva says of Anahi’s schooling, “so she’s behind a little bit. Sometimes she says she doesn’t like herself. Sometimes she will say, ‘I wish I was dead instead.’ And then at school sometimes kids pick on her because she’s short.”

    When discussing Anahi’s future, Bernstein weighs the factors that may influence the girl’s life. As people get older, their energy reserves—both fat and starch—increase, allowing them to go longer without food. “In mitochondrial diseases, though, there’s a competing thing, which is that the wear and tear on your body’s cells apparently over time causes the conditions to actually get worse, even if the shorter-term reserve may be bigger.”

    Though Anahi has a diagnosis now, she is one of only two people with her condition, and their symptoms and mutations aren’t exactly the same. Unlike for other patients who have found a community and learned how their disease will progress, her future remains unclear.

    Though the UDN largely focuses on diagnosing disease, one of its scientists, Matthew Might, heads up an effort to match rare diseases with potential treatments. Might, who directs the University of Alabama at Birmingham’s Hugh Kaul Precision Medicine Institute, earned his PhD in 2007 in computer science and began his academic career researching cybersecurity. But when he and his wife, Cristina Casanova, had their first son, Bertrand, they discovered that he had a rare unknown disease. In 2014, the New Yorker article “One of a Kind” described their journey to diagnose it. A struggle they faced was that competing scientists, intent on taking credit for discoveries, weren’t sharing data on rare diseases—an obstacle the UDN has tried to solve.

    In the process of educating himself on how to treat his son, Might embarked on his own odyssey, as he calls it. “If you read enough Wikipedia, you can do almost anything these days,” he says. He taught himself so much about pharmaceutical chemistry that he received a second faculty appointment in the subject at the University of Utah. He then joined Harvard’s department of biomedical informatics while working as a strategist at the White House for President Obama’s precision medicine initiative.

    Might was asked to be the UDN’s director of precision medicine so he could scale up what he had done for his son: use algorithms to classify known medicines and determine whether they might be used to treat rare diseases. (In the United States, a rare disease is one that affects fewer than 200,000 Americans, which works out to about the same proportion used in the European Union’s definition: one in 2,000 people.) While the number of already identified rare diseases has surpassed 6,000—affecting approximately 25 million Americans and vastly more people worldwide—few treatments exist for the conditions. To address this, Might’s team has built an artificial intelligence agent.

    “It’s really a logical reasoning engine,” Might says, “and the first data set it digested to be reasoning over was about 30 million published medical abstracts—so essentially every paper ever published in medicine.”

    To harness the power of this engine, those attempting to treat a rare disease first examine how the disease affects the body on the cellular level. As in a factory, if any part of the machinery isn’t working correctly, material will either stop moving, accumulate or be absent. If scientists can determine where blockages or improper levels of substances occur, they can then use the software to search for a compound that might create balance in the system.

    “You can ask it very low-level questions, like ‘What’s an inhibitor for this gene?’” Might says. “Or you can ask it very high-level questions, like ‘What is the potential treatment for this condition?’”

    He often finds himself working with parents who, through their own online research, have become experts just as he has. Danny Miller, the father of Carson and Chase, recently reached out to Might to propose a way that an enzyme missing in MEPAN might be circumvented.

    “We checked it out,” Might says, “and sure enough, it looks like he’s right.”

    The lesson in Might’s work is that previous scientific discoveries can be built on; they aren’t investments for a single individual or disease. This addresses the skepticism of those who see research, diagnosis and treatment of rare diseases as too costly.

    “There is essentially no rare disease,” Evan Ashley says, “that doesn’t have a correlate in common disease. You can have variants in that gene that are common and have a small effect on the function of the gene, or you can have variants that are extremely rare and have a massive effect.”

    He gives the example of how studying hypercholesterolemia—a genetic condition that causes unusually high cholesterol—led to treatment of commonplace cholesterol problems.

    “That gene,” he says, “is now the target of the newest and best drug for cholesterol.”

    And whereas Ashley acknowledges the satisfaction in the “Sherlock Holmes element” of the work, he finds the human element most compelling.

    “Each story is literally an odyssey for a family. What makes it so meaningful is that there’s always a face, there’s a person, a family suffering. If you can solve this case, if you were staying up late at night wading through data, the chances are that if you solve it, you help that person and another 10 families with the same condition.”

    5
    IN LIMBO: Doctors suspect Miguel has multiple syndromes.

    For many families, the odyssey that the UDN’s doctors speak of is ongoing and may last for years. Genetic and patient databases are constantly updated, allowing scientists to find new matches, but the wait can be torturous, as it has been for Miguel Bejar and Georgina Guerrero.

    Born in 1977, in the small town of Tizapan, in Jalisco, Mexico, Miguel Bejar moved to Redwood City, Calif., when he was 17. After getting his high school diploma, he took a job as housekeeping assistant at Stanford Hospital. Over more than 20 years, he was promoted first to housekeeping lead, then to housekeeping supervisor, and then transferred to the main operating room, where he is now a lead assistant.

    After he married Guerrero, a dentist’s assistant from Michoacán, they waited more than four years, preparing their home and finances, before starting a family. Their son, Miguel, was born in April 2015. The pregnancy was healthy, though a doctor detected a heart murmur shortly after birth. “He told me that’s pretty normal in babies when they are newborns, and usually it will go away in two or three days,” Bejar recalls.

    But an echocardiogram showed a deformation of the aortic valve and a narrowing of the aorta, which limited blood flow. Doctors successfully performed heart surgery, but three months later, crystals appeared in Miguel’s urine, gathering in his diapers. Further medical tests showed that his red blood cells were slightly smaller than normal, and a genetic test immediately revealed that he had 8p23.1 duplication syndrome—a rare chromosomal anomaly in which the short arm of chromosome 8 is partially duplicated.

    Bejar recalls the doctors explaining the syndrome. “They told me that there were 17 known cases and the syndrome in those situations behaved differently. But they all have cardiac issues.”

    The syndrome, however, didn’t explain all of the symptoms Miguel would soon have. He began growing too quickly—his head even more rapidly than his body. In January 2018, his head’s circumference was 21.8 inches. By October, it was 22. By May 2019, it was 22.4. An MRI showed that his brain was underdeveloped and had large white ventricles. He was soon diagnosed with autism, and his muscles were weak. He walked poorly, fell easily and hadn’t learned to speak. He had kidney stones and would soon need more heart surgery. At the age of 4, he is the size of a 7-year-old, and his head has now surpassed 22.6 inches—almost as big as his father’s.

    “I was a little blessed by having the job at Stanford and having access to doctors,” Bejar recalls. “Without this place, I can’t imagine how other families . . . I mean, for me it has been a little hard. For other families,
    I believe it’s harder.”

    In early 2018, he applied to the UDN, and Miguel was accepted within weeks. The team assigned to Miguel is sequencing the DNA from both his blood and his skin to compare them to determine whether he has mosaicism—a condition in which genetic mutations occur early during development and present only in certain tissues. The team is looking for multiple syndromes, which Bernstein says can be especially challenging: “One condition can mask or confuse you about what’s going on with the other one.”

    As for the next step, that will depend on what current tests reveal—if anything—and what the team decides once it has reviewed the data. After all, more often than not, the UDN does not come up with diagnoses or must wait to connect patients on file to new findings in the scientific literature. Its success rate to date hovers around 28 percent, which means hundreds of people continue to live in limbo.

    While Bejar awaits the results, he tries to reconcile the pain of uncertainty with the tenderness he feels for his son.

    “If I had the opportunity to be a father and this happens again,” he says, “I will take it because it’s one of the best experiences, taking care of a child with necessities. It brings the best out of your human side. You go beyond a lot of your limits on the way you love life, and the way you appreciate life and people.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 9:19 am on September 6, 2019 Permalink | Reply
    Tags: "Stanford chemists discover water microdroplets spontaneously produce hydrogen peroxide", , , Stanford University   

    From Stanford University: “Stanford chemists discover water microdroplets spontaneously produce hydrogen peroxide” 

    Stanford University Name
    From Stanford University

    August 26, 2019
    Nathan Collins, Stanford News Service
    (650) 228-4677
    nac@stanford.edu

    Despite its abundance, water retains a great many secrets. Among them, Stanford chemists have discovered, is that water microdroplets spontaneously produce hydrogen peroxide.

    Water is everywhere on Earth, but maybe that just gives it more space to hide its secrets. Its latest surprise, Stanford researchers report Aug. 26 in Proceedings of the National Academy of Sciences, is that microscopic droplets of water spontaneously produce hydrogen peroxide.

    1
    Chemistry Professor Richard Zare and his lab have shown that water microdroplets spontaneously – and unexpectedly – produce hydrogen peroxide. (Image credit: L.A. Cicero)

    The discovery could pave the way for greener ways to produce the molecule, a common bleaching agent and disinfectant, said Richard Zare, the Marguerite Blake Wilbur Professor in Natural Science and a professor of chemistry in the Stanford School of Humanities and Sciences.

    “Water is one of the most commonly found materials, and it’s been studied for years and years and you would think that there was nothing more to learn about this molecule. But here’s yet another surprise,” said Zare, who is also a member of Stanford Bio-X.

    The discovery was made serendipitously while Zare and his lab were studying a new, more efficient way to create gold nanostructures in tiny water droplets known as microdroplets. To make those structures, the team added an additional molecule called a reducing agent. As a control test, Zare suggested seeing if they could create gold nanostructures without the reducing agent. Theoretically that should have been impossible, but it worked anyway – hinting at an as yet undiscovered feature of microdroplet chemistry.

    The team eventually traced those results to the presence of a molecule called hydroxyl – a single hydrogen atom paired with an oxygen atom – that can also act as a reducing agent. That equally unexpected result led Katherine Walker, at the time a graduate student in Zare’s lab, to wonder whether hydrogen peroxide – a molecule with two hydrogen and two oxygen atoms – was also present.

    To find out, Zare, Walker, staff scientist Jae Kyoo Lee and colleagues conducted a series of tests, the simplest of which involved spraying ostensibly pure water microdroplets onto a surface treated so that it would turn blue in the presence of hydrogen peroxide – and turn blue it did. Additional tests confirmed that water microdroplets spontaneously form hydrogen peroxide, that smaller microdroplets produced higher concentrations of the molecule, and that hydrogen peroxide was not lost when the microdroplets recombined into bulk water.

    Video by Jae Kyoo Lee and Hyun Soo Han

    In this demonstration, a test strip turns blue when sprayed with water microdroplets, indicating the presence of hydrogen peroxide.

    The researchers ruled out a number of possible explanations before arriving at what they argue is the most likely explanation for hydrogen peroxide’s presence. They suggest that a strong electric field near the surface of water microdroplets in air triggers hydroxyl molecules to bind into hydrogen peroxide.

    Although the results are something of a basic science curiosity, Zare said, they could have important practical consequences. Hydrogen peroxide is an important commercial and industrial chemical, most often manufactured through an ecologically unfriendly process. The new discovery could help make those methods greener, Zare said, and it could lead to simpler ways to disinfect surfaces – simply spraying water microdroplets on a table or floor might be enough to clean it.

    “I think it could be one of the most important things I’ve ever done,” Zare said.

    Additional authors include Robert Waymouth, the Robert Eckles Swain Professor in Chemistry; Friedrich Prinz, the Finmeccanica Professor and a professor of mechanical engineering and of materials science and engineering; postdoctoral fellow Hyun Soo Han; and researchers from the Institute for Basic Science and the Daegu Gyeongbuk Institute of Science and Technology.

    Zare is also a member of the Cardiovascular Institute, the Stanford Cancer Institute, Stanford ChEM-H, the Stanford Woods Institute for the Environment and the Wu Tsai Neurosciences Institute.

    The research was funded in part by a grant from the U.S. Air Force Office of Scientific Research and the Institute for Basic Science, South Korea.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
  • richardmitnick 8:23 am on September 6, 2019 Permalink | Reply
    Tags: , Rechargeable lithium metal batteries, , Stanford University   

    From Stanford University and SLAC: “New coating developed by Stanford researchers brings lithium metal battery closer to reality” 

    Stanford University Name
    From Stanford University

    August 26, 2019
    Mark Golden

    1
    A new coating could make lightweight lithium metal batteries safe and long lasting, a boon for development of next-generation electric vehicles. (Image credit: Shutterstock)

    Hope has been restored for the rechargeable lithium metal battery – a potential battery powerhouse relegated for decades to the laboratory by its short life expectancy and occasional fiery demise while its rechargeable sibling, the lithium-ion battery, now rakes in more than $30 billion a year.

    A team of researchers at Stanford University and SLAC National Accelerator Laboratory has invented a coating that overcomes some of the battery’s defects, described in a paper published Aug. 26 in Joule.

    In laboratory tests, the coating significantly extended the battery’s life. It also dealt with the combustion issue by greatly limiting the tiny needlelike structures – or dendrites – that pierce the separator between the battery’s positive and negative sides. In addition to ruining the battery, dendrites can create a short circuit within the battery’s flammable liquid. Lithium-ion batteries occasionally have the same problem, but dendrites have been a non-starter for lithium metal rechargeable batteries to date.

    “We’re addressing the holy grail of lithium metal batteries,” said Zhenan Bao, a professor of chemical engineering, who is senior author of the paper along with Yi Cui, professor of materials science and engineering and of photon science at SLAC. Bao added that dendrites had prevented lithium metal batteries from being used in what may be the next generation of electric vehicles.

    The promise

    Lithium metal batteries can hold at least a third more power per pound as lithium-ion batteries do and are significantly lighter because they use lightweight lithium for the positively charged end rather than heavier graphite. If they were more reliable, these batteries could benefit portable electronics from notebook computers to cell phones, but the real pay dirt, Cui said, would be for cars. The biggest drag on electric vehicles is that their batteries spend about a fourth of their energy carrying themselves around. That gets to the heart of EV range and cost.

    2
    Lead authors and PhD students David Mackanic, left, and Zhiao Yu in front of their battery tester. Yu is holding a dish of already tested cells that they call the “battery graveyard.” (Image credit: Mark Golden)

    “The capacity of conventional lithium-ion batteries has been developed almost as far as it can go,” said Stanford PhD student David Mackanic, co-lead author of the study. “So, it’s crucial to develop new kinds of batteries to fulfill the aggressive energy density requirements of modern electronic devices.”

    The team from Stanford and SLAC tested their coating on the positively charged end – called the anode – of a standard lithium metal battery, which is where dendrites typically form. Ultimately, they combined their specially coated anodes with other commercially available components to create a fully operational battery. After 160 cycles, their lithium metal cells still delivered 85 percent of the power that they did in their first cycle. Regular lithium metal cells deliver about 30 percent after that many cycles, rendering them nearly useless even if they don’t explode.

    The new coating prevents dendrites from forming by creating a network of molecules that deliver charged lithium ions to the electrode uniformly. It prevents unwanted chemical reactions typical for these batteries and also reduces a chemical buildup on the anode, which quickly devastates the battery’s ability to deliver power.

    “Our new coating design makes lithium metal batteries stable and promising for further development,” said the other co-lead author, Stanford PhD student Zhiao Yu.

    The group is now refining their coating design to increase capacity retention and testing cells over more cycles.

    “While use in electric vehicles may be the ultimate goal,” said Cui, “commercialization would likely start with consumer electronics to demonstrate the battery’s safety first.”

    Zhenan Bao and Yi Cui are also senior fellows at Stanford’s Precourt Institute for Energy. Other Stanford researchers include Jian Qin, assistant professor of chemical engineering; postdoctoral scholars Dawei Feng, Jiheong James Kang, Minah Lee, Chibueze Amanchukwu, Xuzhou Yan, Hansen Wang and Kai Liu; students Wesley Michaels, Allen Pei, Shucheng Chen and Yuchi Tsao; and visiting scholar Qiuhong Zhang from Nanjing University.

    This work was supported by the U.S. Department of Energy Office of Energy Efficiency & Renewable Energy. The facility used at Stanford is supported by the National Science Foundation.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
  • richardmitnick 8:38 am on September 5, 2019 Permalink | Reply
    Tags: "Making California’s Water Supply Resilient", A fair amount of water is lost to system leaks before it even reaches customers., A water resilience portfolio can look different from region to region., A water supply portfolio is the combination of water supply sources available to a utility., California Gov. Gavin Newsom recently signed an executive order to develop a comprehensive strategy for making the state’s water system climate-resilient., Climate change is magnifying many of our current water challenges., Communities with lower densities may find a centralized recycling plant as a better solution., Encouraging regional collaboration; system-level thinking; and innovation especially in water governance and business models are essential elements of any state-wide water strategy., In developing such a portfolio utilities and regions should not only focus on the number of sources but also need to think about the capacity of each supply., In highly urbanized regions solutions such as on-site reuse work well., Increased wildfires especially in urban/wildland interface is affecting water quality., It is important for regions to identify the value and risks of existing and potential water supply options., It is important to rely on more than one supply source and develop a water portfolio that is comprised of multiple water options., Replacing and fixing our aging infrastructure requires a holistic approach and it should also include changing and revamping our funding and financial model., Snowmelts are earlier and faster than before depriving us from our natural reservoir that used to hold much of our summer supply., Stanford University, The order calls for a broad portfolio of collaborative strategies to deal with outdated water infrastructure; unsafe drinking water; flood risks and depleted groundwater aquifers., The state needs to recognize these parameters and provide regions with broad guidelines.   

    From Stanford University: “Making California’s Water Supply Resilient” 

    Stanford University Name
    From Stanford University

    September 03, 2019
    Michelle Horton

    1
    San Luis Reservoir, the fifth largest in California, stores water from the San Joaquin-Sacramento River Delta. Photo Credit: Flickr/mlhradio

    As with the stock market, climate change requires a diversified portfolio of solutions. California Gov. Gavin Newsom recently signed an executive order to develop a comprehensive strategy for making the state’s water system climate-resilient. The order calls for a broad portfolio of collaborative strategies to deal with outdated water infrastructure, unsafe drinking water, flood risks and depleted groundwater aquifers.

    2

    In a related study published earlier this year [Nature Sustainability], Stanford researchers Newsha Ajami and Patricia (Gonzales) Whitby examined effective strategies to rising water scarcity concerns. Ajami is director of Urban Water Policy at Stanford’s Water in the West program and a hydrologist specializing in sustainable water resource management. Whitby is a recent Ph.D. graduate from Stanford’s civil and environmental engineering department and currently a water engineer at environmental consulting firm Brown and Caldwell. Below, they discuss their research and how a diversified water portfolio can meet the water needs of California into the future.

    How does a diversified water portfolio reduce risks associated with water supply?

    Ajami: Developing a water supply portfolio means moving away from dependence on one water source such as imported water or groundwater in order to develop a number of other water sources by incorporating local and regional solutions including conservation and efficiency, water recycling and reuse, rainwater and stormwater harvesting and desalination. The golden rule in an investment portfolio is to have diversification which prevents short-term and long-term risks. The same rule applies to a diversified water portfolio. In order to minimize the risk of short-term and long-term challenges and disruptions due to failing infrastructure or climate change impacts including intensified droughts and floods, it is important to rely on more than one supply source and develop a water portfolio that is comprised of multiple water options in order to increase systematic flexibility and resiliency. In developing such a portfolio, utilities and regions should not only focus on the number of sources but also need to think about the capacity of each supply. Our team has developed a water reliance index which can help measure these goals at both the utility and regional level.

    Whitby: A water supply portfolio is the combination of water supply sources available to a utility. Diversifying means we’re not putting all of our eggs in one basket, so if something happens to one of the supplies like a disruption to the physical infrastructure or a water quality concern or a cutback due to drought, we still have a portfolio of other options available. Water supply diversification should pursue different types of water sources such that each supply has different risks and also different strengths. For example, water reuse is typically considered a robust supply that is resilient to drought. Similarly, diversification means not only having many different water sources available, but also leveraging those sources to reduce stress on the more traditional supplies.

    What key priorities would you expect California’s water resilience portfolio to focus on?

    Ajami: A water resilience portfolio can look different from region to region as California faces different challenges, opportunities, risks and limitations across the state. It is important for regions to identify the value and risks of existing and potential water supply options and focus on projects that not only enhance access to clean water but also deliver broader environmental and societal benefits such as green infrastructure. In highly urbanized regions, solutions such as on-site reuse work well, while communities with lower densities may find a centralized recycling plant as a better solution. The state needs to recognize these parameters and provide regions with broad guidelines while enabling and encouraging development of collaborative regional strategies. A model similar to the Renewable Energy Portfolio comes to mind, where regional and a statewide water diversification portfolio goals are set and then incentivized.

    In a recent study [above] our team developed a cap and trade goal-based trading model that enables a region to reach their water diversification portfolio goals by working together and taking advantage of regional opportunities to develop a diverse set of water solutions. Such innovative system level solutions can help water utilities coordinate their efforts, overcome fragmentation and share both financial and water resources while also gradually adjusting their business model.

    What role does climate change play in future planning?

    Ajami: Climate change is magnifying many of our current water challenges. Intensified droughts and floods are demonstrating the limitations of our traditional infrastructure model such as dams and wastewater treatment plants. The shift in our hydrological cycle means the conventional ways we managed our complex water systems aren’t working. The new normal looks very different, as precipitation patterns have shifted, and we are receiving more rain than snow. Also due to higher temperatures, snow melts earlier and faster than before, depriving us from our natural reservoir that used to hold much of our summer supply. Sea level rise is threatening our coastal groundwater basins and wastewater treatment plants. Increased wildfires especially in urban/wildland interface is affecting water quality. Overall climate change is interrupting our water systems. This means climate change has to be front and center in every infrastructure planning process. Our 21st century infrastructure model should look very different from our 20th century model, incorporating more nature-based solutions that can increase our system’s resiliency and flexibility.

    Can this order also help fix California’s outdated drinking water infrastructure?

    Ajami: Absolutely! Replacing and fixing our aging infrastructure requires a holistic approach and it should also include changing and revamping our funding and financial model. If you look at your energy or telephone bill there is a line item that provides funding to ensure access to telecommunication and energy infrastructure for rural and low-income communities. This model provides long-term sustainable and stable funding that is essential. This is exactly what we need in the water sector and what we do not have. Gov. Newsom has certainly identified access to clean water as one of his administrations major issues. His team has certainly tried to find resources to make it happen – which is a great first step – but I believe a model similar to energy and telecommunications sectors are needed to guarantee long-term sustainable and resilient solutions for every community in California.

    Whitby: Definitely. Aging infrastructure is one of the risk factors affecting our water systems today. A fair amount of water is lost to system leaks before it even reaches customers. Incentives to diversify and strengthen our water portfolios provide an opportunity to not only retrofit and expand infrastructure, but also to re-invent and fortify our water system for the next century.

    Based on your research what factors are necessary for successful implementation of a state-wide portfolio?

    Ajami: Encouraging regional collaboration, system-level thinking and innovation especially in water governance and business models are essential elements of any state-wide water strategy. In response to some of our statewide water challenges, communities around California have started embracing alternative water solutions and diversifying their water portfolio by introducing demand side management strategies such as water reuse, stormwater and rainwater harvesting and desalinization among others. These new water sources are slowly disrupting the top-down model of the water sector and introducing more flexibility and resilience to local water systems, especially during droughts and other natural disasters. But these efforts are not often coordinated, and their implementation suffers from our outdated and fragmented governance models which need to be disrupted and changed.

    Whitby: Collaboration and innovation. Collaboration because our water systems are inherently very fragmented with jurisdictions that don’t always overlap with municipalities, counties or other agencies such as regulators and land-use planners. Working together can open up doors to identify opportunities that are both locally minded and regionally relevant. Innovation needs to happen not only on the technology side but also in the form of creative governance and financing mechanisms to make the necessary changes possible.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
  • richardmitnick 8:36 am on August 20, 2019 Permalink | Reply
    Tags: A heat shield just 10 atoms thick, , , Stanford University   

    From Stanford University: “Stanford researchers build a heat shield just 10 atoms thick to protect electronic devices” 

    Stanford University Name
    From Stanford University

    August 16, 2019
    Tom Abate

    1
    This greatly magnified image shows four layers of atomically thin materials that form a heat-shield just two to three nanometers thick, or roughly 50,000 times thinner than a sheet of paper. (Image credit: National Institute of Standards and Technology)

    Excess heat given off by smartphones, laptops and other electronic devices can be annoying, but beyond that it contributes to malfunctions and, in extreme cases, can even cause lithium batteries to explode.

    To guard against such ills, engineers often insert glass, plastic or even layers of air as insulation to prevent heat-generating components like microprocessors from causing damage or discomforting users.

    Now, Stanford researchers have shown that a few layers of atomically thin materials, stacked like sheets of paper atop hot spots, can provide the same insulation as a sheet of glass 100 times thicker. In the near term, thinner heat shields will enable engineers to make electronic devices even more compact than those we have today, said Eric Pop, professor of electrical engineering and senior author of a paper published Aug. 16 in Science Advances.

    “We’re looking at the heat in electronic devices in an entirely new way,” Pop said.

    Detecting sound as heat

    The heat we feel from smartphones or laptops is actually an inaudible form of high-frequency sound. If that seems crazy, consider the underlying physics. Electricity flows through wires as a stream of electrons. As these electrons move, they collide with the atoms of the materials through which they pass. With each such collision an electron causes an atom to vibrate, and the more current flows, the more collisions occur, until electrons are beating on atoms like so many hammers on so many bells – except that this cacophony of vibrations moves through the solid material at frequencies far above the threshold of hearing, generating energy that we feel as heat.

    Thinking about heat as a form of sound inspired the Stanford researchers to borrow some principles from the physical world. From his days as a radio DJ at Stanford’s KZSU 90.1 FM, Pop knew that music recording studios are quiet thanks to thick glass windows that block the exterior sound. A similar principle applies to the heat shields in today’s electronics. If better insulation were their only concern, the researchers could simply borrow the music studio principle and thicken their heat barriers. But that would frustrate efforts to make electronics thinner. Their solution was to borrow a trick from homeowners, who install multi-paned windows – usually, layers of air between sheets of glass with varying thickness – to make interiors warmer and quieter.

    “We adapted that idea by creating an insulator that used several layers of atomically thin materials instead of a thick mass of glass,” said postdoctoral scholar Sam Vaziri, the lead author on the paper.

    Atomically thin materials are a relatively recent discovery. It was only 15 years ago that scientists were able to isolate some materials into such thin layers. The first example discovered was graphene, which is a single layer of carbon atoms and, ever since it was found, scientists have been looking for, and experimenting with, other sheet-like materials. The Stanford team used a layer of graphene and three other sheet-like materials – each three atoms thick – to create a four-layered insulator just 10 atoms deep. Despite its thinness, the insulator is effective because the atomic heat vibrations are dampened and lose much of their energy as they pass through each layer.

    To make nanoscale heat shields practical, the researchers will have to find some mass production technique to spray or otherwise deposit atom-thin layers of materials onto electronic components during manufacturing. But behind the immediate goal of developing thinner insulators looms a larger ambition: Scientists hope to one day control the vibrational energy inside materials the way they now control electricity and light. As they come to understand the heat in solid objects as a form of sound, a new field of phononics is emerging, a name taken from the Greek root word behind telephone, phonograph and phonetics.

    “As engineers, we know quite a lot about how to control electricity, and we’re getting better with light, but we’re just starting to understand how to manipulate the high-frequency sound that manifests itself as heat at the atomic scale,” Pop said.

    Eric Pop is an affiliate of the Precourt Institute for Energy. Stanford authors include former postdoctoral scholars Eilam Yalon and Miguel Muñoz Rojo, and graduate students Connor McClellan, Connor Bailey, Kirby Smithe, Alexander Gabourie, Victoria Chen, Sanchit Deshmukh and Saurabh Suryavanshi. Other authors are from Theiss Research and the National Institute of Standards and Technology.

    This research was supported by the Stanford Nanofabrication Facility, the Stanford Nano Shared Facilities, the National Science Foundation, the Semiconductor Research Corporation, the Defense Advanced Research Projects Agency, the Air Force Office of Scientific Research, the Stanford SystemX Alliance, the Knut and Alice Wallenberg Foundation, the Stanford Graduate Fellowship program and the National Institute of Standards and Technology.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 8:54 am on August 17, 2019 Permalink | Reply
    Tags: "Wireless sensors that stick to the skin to track our health", , , , Stanford engineers have developed a way to detect physiological signals emanating from the skin with sensors that stick like band-aids and beam wireless readings to a receiver clipped onto clothing., Stanford University, The BodyNet sticker, The researchers had to create an antenna that could stretch and bend like skin.   

    From Stanford University: “Wireless sensors that stick to the skin to track our health” 

    Stanford University Name
    From Stanford University

    August 16, 2019
    Tom Abate
    (650) 736-2245
    tabate@stanford.edu

    1
    The rubber sticker attached to the wrist can bend and stretch as the person’s skin moves, beaming pulse readings to a receiver clipped to the person’s clothing. (Image credit: Bao Lab)

    We tend to take our skin’s protective function for granted, ignoring its other roles in signaling subtleties like a fluttering heart or a flush of embarrassment.

    2
    Using metallic ink, researchers screen-print an antenna and sensor onto a stretchable sticker designed to adhere to skin and track pulse and other health indicators, and beam these readings to a receiver on a person’s clothing. (Image credit: Bao Lab)

    Now, Stanford engineers have developed a way to detect physiological signals emanating from the skin with sensors that stick like band-aids and beam wireless readings to a receiver clipped onto clothing.

    To demonstrate this wearable technology, the researchers stuck sensors to the wrist and abdomen of one test subject to monitor the person’s pulse and respiration by detecting how their skin stretched and contracted with each heartbeat or breath. Likewise, stickers on the person’s elbows and knees tracked arm and leg motions by gauging the minute tightening or relaxation of the skin each time the corresponding muscle flexed.

    Zhenan Bao, the chemical engineering professor whose lab described the system in an Aug. 15 article in Nature Electronics, thinks this wearable technology, which they call BodyNet, will first be used in medical settings such as monitoring patients with sleep disorders or heart conditions. Her lab is already trying to develop new stickers to sense sweat and other secretions to track variables such as body temperature and stress. Her ultimate goal is to create an array of wireless sensors that stick to the skin and work in conjunction with smart clothing to more accurately track a wider variety of health indicators than the smart phones or watches consumers use today.

    “We think one day it will be possible to create a full-body skin-sensor array to collect physiological data without interfering with a person’s normal behavior,” said Bao, who is also the K.K. Lee Professor in the School of Engineering.

    Stretchable, comfortable, functional

    Postdoctoral scholars Simiao Niu and Naoji Matsuhisa led the 14-person team that spent three years designing the sensors. Their goal was to develop a technology that would be comfortable to wear and have no batteries or rigid circuits to prevent the stickers from stretching and contracting with the skin.

    Their eventual design met these parameters with a variation of the RFID – radiofrequency identification – technology used to control keyless entry to locked rooms. When a person holds an ID card up to an RFID receiver, an antenna in the ID card harvests a tiny bit of RFID energy from the receiver and uses this to generate a code that it then beams back to the receiver.

    The BodyNet sticker is similar to the ID card: It has an antenna that harvests a bit of the incoming RFID energy from a receiver on the clothing to power its sensors. It then takes readings from the skin and beams them back to the nearby receiver.

    But to make the wireless sticker work, the researchers had to create an antenna that could stretch and bend like skin. They did this by screen-printing metallic ink on a rubber sticker. However, whenever the antenna bent or stretched, those movements made its signal too weak and unstable to be useful.

    To get around this problem, the Stanford researchers developed a new type of RFID system that could beam strong and accurate signals to the receiver despite constant fluctuations. The battery-powered receiver then uses Bluetooth to periodically upload data from the stickers to a smartphone, computer or other permanent storage system.

    The initial version of the stickers relied on tiny motion sensors to take respiration and pulse readings. The researchers are now studying how to integrate sweat, temperature and other sensors into their antenna systems.

    To move their technology beyond clinical applications and into consumer-friendly devices, the researchers need to overcome another challenge – keeping the sensor and receiver close to each other. In their experiments, the researchers clipped a receiver on clothing just above each sensor. One-to-one pairings of sensors and receivers would be fine in medical monitoring, but to create a BodyNet that someone could wear while exercising, antennas would have to be woven into clothing to receive and transmit signals no matter where a person sticks a sensor.

    Bao is also a senior fellow of the Precourt Institute for Energy, a member of Stanford Bio-X, a faculty fellow of Stanford ChEM-H, an affiliate of the Stanford Woods Institute for the Environment and a member of the Wu Tsai Neurosciences Institute. Other Stanford co-authors are Jeffrey B.-H. Tok, research scientist; Ada Poon, associate professor of electrical engineering; William Burnett, adjunct professor of mechanical engineering; postdoctoral scholars Yuanwen Jiang and Jinxing Li; graduate student Jiechen Wang; and former visiting scholar Youngjun Yun and former postdoctoral scholars Sihong Wang, Xuzhou Yan and Levent Beker. Researchers from Singapore’s Nanyang Technological University also co-authored the study.

    This research was supported by Samsung Electronics; the Singapore Agency for Science, Technology and Research; the Japan Society for the Promotion of Science; and the Stanford Precision Health and Integrated Diagnosis Center.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
  • richardmitnick 9:39 am on August 8, 2019 Permalink | Reply
    Tags: "Stanford researchers design a light-trapping, , , color-converting crystal", , , , , Photonic crystal cavities, , Stanford University   

    From Stanford University: “Stanford researchers design a light-trapping, color-converting crystal” 

    Stanford University Name
    From Stanford University

    August 7, 2019

    Taylor Kubota
    Stanford News Service
    (650) 724-7707
    tkubota@stanford.edu

    1
    Researchers propose a microscopic structure that changes laser light from infrared to green and traps both wavelengths of light to improve efficiency of that transformation. This type of structure could help advance telecommunication and computing technologies. (Image credit: Getty Images)

    Five years ago, Stanford postdoctoral scholar Momchil Minkov encountered a puzzle that he was impatient to solve. At the heart of his field of nonlinear optics are devices that change light from one color to another – a process important for many technologies within telecommunications, computing and laser-based equipment and science. But Minkov wanted a device that also traps both colors of light, a complex feat that could vastly improve the efficiency of this light-changing process – and he wanted it to be microscopic.

    “I was first exposed to this problem by Dario Gerace from the University of Pavia in Italy, while I was doing my PhD in Switzerland. I tried to work on it then but it’s very hard,” Minkov said. “It has been in the back of my mind ever since. Occasionally, I would mention it to someone in my field and they would say it was near-impossible.”

    In order to prove the near-impossible was still possible, Minkov and Shanhui Fan, professor of electrical engineering at Stanford, developed guidelines for creating a crystal structure with an unconventional two-part form. The details of their solution were published Aug. 6 in Optica, with Gerace as co-author. Now, the team is beginning to build its theorized structure for experimental testing.

    2
    An illustration of the researchers’ design. The holes in this microscopic slab structure are arranged and resized in order to control and hold two wavelengths of light. The scale bar on this image is 2 micrometers, or two millionths of a meter. (Image credit: Momchil Minkov)

    A recipe for confining light

    Anyone who’s encountered a green laser pointer has seen nonlinear optics in action. Inside that laser pointer, a crystal structure converts laser light from infrared to green. (Green laser light is easier for people to see but components to make green-only lasers are less common.) This research aims to enact a similar wavelength-halving conversion but in a much smaller space, which could lead to a large improvement in energy efficiency due to complex interactions between the light beams.

    The team’s goal was to force the coexistence of the two laser beams using a photonic crystal cavity, which can focus light in a microscopic volume. However, existing photonic crystal cavities usually only confine one wavelength of light and their structures are highly customized to accommodate that one wavelength.

    So instead of making one uniform structure to do it all, these researchers devised a structure that combines two different ways to confine light, one to hold onto the infrared light and another to hold the green, all still contained within one tiny crystal.

    “Having different methods for containing each light turned out to be easier than using one mechanism for both frequencies and, in some sense, it’s completely different from what people thought they needed to do in order to accomplish this feat,” Fan said.

    After ironing out the details of their two-part structure, the researchers produced a list of four conditions, which should guide colleagues in building a photonic crystal cavity capable of holding two very different wavelengths of light. Their result reads more like a recipe than a schematic because light-manipulating structures are useful for so many tasks and technologies that designs for them have to be flexible.

    “We have a general recipe that says, ‘Tell me what your material is and I’ll tell you the rules you need to follow to get a photonic crystal cavity that’s pretty small and confines light at both frequencies,’” Minkov said.

    Computers and curiosity

    If telecommunications channels were a highway, flipping between different wavelengths of light would equal a quick lane change to avoid a slowdown – and one structure that holds multiple channels means a faster flip. Nonlinear optics is also important for quantum computers because calculations in these computers rely on the creation of entangled particles, which can be formed through the opposite process that occurs in the Fan lab crystal – creating twinned red particles of light from one green particle of light.

    Envisioning possible applications of their work helps these researchers choose what they’ll study. But they are also motivated by their desire for a good challenge and the intricate strangeness of their science.

    “Basically, we work with a slab structure with holes and by arranging these holes, we can control and hold light,” Fan said. “We move and resize these little holes by billionths of a meter and that marks the difference between success and failure. It’s very strange and endlessly fascinating.”

    These researchers will soon be facing off with these intricacies in the lab, as they are beginning to build their photonic crystal cavity for experimental testing.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
  • richardmitnick 11:43 am on July 31, 2019 Permalink | Reply
    Tags: , , , Stanford University, Technologies that run on light   

    From Stanford University: “Stanford researchers developing technologies that run on light” 

    Stanford University Name
    From Stanford University

    July 24, 2019
    Taylor Kubota
    Stanford News Service:
    (650) 724-7707
    tkubota@stanford.edu

    Jen Dionne
    Stanford University
    (650) 736-2286
    jdionne@stanford.edu

    1
    Stanford researchers are developing a nanoscale photon diode that could contribute to technologies that run on light rather than electricity. (Image credit: Getty Images)

    The future of faster, more efficient information processing may come down to light rather than electricity. Mark Lawrence, a postdoctoral scholar in materials science and engineering at Stanford, has moved a step closer to this future with a scheme to make a photon diode – a device that allows light to only flow in one direction – which, unlike other light-based diodes, is small enough for consumer electronics.

    All he had to do was design smaller-than-microscopic structures and break a fundamental symmetry of physics.

    “Diodes are ubiquitous in modern electronics, from LEDs (light emitting diodes) to solar cells (essentially LEDs run in reverse) to integrated circuits for computing and communications,” said Jennifer Dionne, associate professor of materials science and engineering and senior author on the paper describing this work, published July 24 in Nature Communications. “Achieving compact, efficient photonic diodes is paramount to enabling next-generation computing, communication and even energy conversion technologies.”

    At this point, Dionne and Lawrence have designed the new photon diode and checked their design with computer simulations and calculations. They’ve also created the necessary nanostructures – the custom smaller-than-microscopic components – and are installing the light source that they hope will bring their theorized system to life.

    “One grand vision is to have an all-optical computer where electricity is replaced completely by light and photons drive all information processing,” Lawrence said. “The increased speed and bandwidth of light would enable faster solutions to some of the hardest scientific, mathematical and economic problems.”

    Spinning light, breaking laws

    The main challenges of a light-based diode are two-fold. First, following the laws of thermodynamics, light should move forward through an object with no moving parts in the exact same way it would move backward. Making it flow in one direction requires new materials that overturn this law, breaking what’s known as time-reversal symmetry. Second, light is much more difficult to manipulate than electricity because it doesn’t have charge.

    Other researchers have previously tackled these challenges by running light through a polarizer – which makes the light waves oscillate in a uniform direction – and then through a crystalline material within a magnetic field, which rotates the polarization of light. Finally, another polarizer matched to that polarization ushers the light out with near-perfect transmission. If light is run through the device in the opposite direction, no light gets out.

    Lawrence described the one-way action of this three-part setup, known as a Faraday isolator, as similar to taking a moving sidewalk between two doors, where the sidewalk plays the role of the magnetic field. Even if you tried to go backward through the last door, the sidewalk would usually prevent you from reaching the first door.

    In order to produce a strong enough rotation of the light polarization, these kinds of diodes must be relatively large – much too large to fit into consumer computers or smartphones. As an alternative, Dionne and Lawrence came up with a way of creating rotation in crystal using another light beam instead of a magnetic field. This beam is polarized so that its electrical field takes on a spiral motion which, in turn, generates rotating acoustic vibrations in the crystal that give it magnetic-like spinning abilities and enable more light to get out. To make the structure both small and efficient, the Dionne lab relied on its expertise in manipulating and amplifying light with tiny nano-antennas and nanostructured materials called metasurfaces.

    The researchers designed arrays of ultra-thin silicon disks that work in pairs to trap the light and enhance its spiraling motion until it finds its way out. This results in high transmission in the forward direction. When illuminated in the backwards direction, the acoustic vibrations spin in the opposite direction and help cancel out any light trying to exit. Theoretically, there is no limit to how small this system could be. For their simulations, they imagined structures as thin as 250 nanometers. (For reference, a sheet of paper is about 100,000 nanometers thick.)

    What’s possible

    Big picture, the researchers are particularly interested in how their ideas might influence the development of brain-like computers, called neuromorphic computers. This goal will also require additional advances in other light-based components, such as nanoscale light sources and switches.

    “Our nanophotonic devices may allow us to mimic how neurons compute – giving computing the same high interconnectivity and energy efficiency of the brain, but with much faster computing speeds,” Dionne said.

    “We can take these ideas in so many directions,” Lawrence said. “We haven’t found the limits of classical or quantum optical computing and optical information processing. Someday we could have an all-optical chip that does everything electronics do and more.”

    To read all stories about Stanford science, subscribe to the biweekly Stanford Science Digest.

    Dionne is also a member of Stanford Bio-X, an affiliate of the Precourt Institute for Energy and a member of the Wu Tsai Neurosciences Institute at Stanford.

    This research was funded by the Air Force Office of Scientific Research, the National Science Foundation, and the Alfred P. Sloan Foundation.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus. No image credit

    Stanford University

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

    Stanford University Seal

     
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