For some of the poorest countries on Earth,the COVID-19 pandemic has posed alife-or-death quandary:If people continue to work,the virus might spread unchecked.But if they have to stay at home to limit the contagion,hunger and malnutrition could soar.In the West African nation of Togo,policymakers decided that modest support payments to the neediest people are part of the solution—and they turned for help to the Center for Effective Global Action(CEGA)at UC Berkeley.The partnership has explored how artificial intelligence—driven by big data and machine learning,satellite images and phone records—can help to pinpoint the areas where needs are most urgent. 查看详细>>

Scientists at UC Berkeley and Western University in Canada have used brain imaging to map the cerebellum,a formerly underappreciated neural region that contains the vast majority of the brain’s neurons,hence its Latin moniker“little brain.”The results of their study appear this month in the Nature Neuroscience journal.The map can be viewed at this link.“This is the first time the human cerebellum has been mapped using task-based data on the same set of subjects at this detail,”said study lead author Maedbh King,a Ph.D.student in neuroscience at Berkeley.Tucked into the base of the skull,the cerebellum plays akey role in higher-order cognition,such as language,working memory and problem-solving.It has also been linked to such mental disorders as schizophrenia and autism and to learning differences like dyslexia.King,Berkeley neuroscientist Richard Ivry and Western University computational neuroscience professor Jörn Diedrichsen used functional magnetic resonance imaging(fMRI)to monitor brain activity as study participants performed numerous tasks.They used the data to create adetailed map of the cerebellum that can be used as aresearch tool to better understand its function and to advance research into certain disorders. 查看详细>>

Cannabis is unlike any other agricultural crop.Because of its circuitous history—once illegal to grow,and now legal but heavily regulated—cannabis has cast aunique footprint on the environment and the communities of farmers who grow it.UC Berkeley’s new Cannabis Research Center,announced today by amultidisciplinary team of faculty,will explore how cannabis production impacts the environment and society,and how these impacts will evolve under new regulations set in place by legalization.While other research groups in the University of California are focusing on the individual and public health ramifications of cannabis,the center will be the first in the UC system to explore oft-overlooked dimensions of cannabis growth.Berkeley News spoke with center co-directors Van Butsic and Ted Grantham,both assistant cooperative extension specialists in UC Berkeley’s Department of Environmental Science,Policy and Management,to learn more about the state of cannabis production in California and the center’s goals. 查看详细>>

From spoons to stuffed animals,humans learn early in life how to pick up objects that have avariety of shapes,textures and sizes.A new machine-learning algorithm developed by engineers at UC Berkeley can teach robots to grasp and carry items with similar dexterity.The algorithm helps“ambidextrous”robots equipped with different types of grippers—for example,a suction gripper and aparallel-jaw gripper—decide which gripper to use for any given object.“Any single gripper cannot handle all objects,”said Jeff Mahler,a postdoctoral researcher at UC Berkeley and lead author of anew paper describing the advance,published this week in Science Robotics.“For example,a suction cup cannot create aseal on porous objects such as clothing,and parallel-jaw grippers may not be able to reach both sides of some tools and toys.‘Ambidextrous’robots offer greater diversity.”The technology could be especially useful in fulfillment centers for e-commerce companies like Amazon,which rely on robots for packaging.“When you are in awarehouse putting together packages for delivery,objects vary considerably,”said Ken Goldberg,a UC Berkeley professor with joint appointments in the Department of Electrical Engineering and Computer Sciences and the Department of Industrial Engineering and Operations Research.“We need avariety of grippers to handle avariety of objects.” 查看详细>>

CRISPR-Cas9 is arevolutionary tool in part because of its versatility:created by bacteria to chew up viruses,it works equally well in human cells to do all sorts of genetic tricks,including cutting and pasting DNA,making pinpoint mutations and activating or inactivating agene.UC Berkeley researchers have now made it even more versatile by giving it an“on”switch,allowing users to keep the Cas9 gene editor turned off in all cells except its designated target.The redesigned Cas9 enzyme—which the researchers refer to as ProCas9—is fully functional except for containing alength of protein that needs to be snipped before the enzyme can bind and cut DNA.If scientists insert ashort length of protein that can be cut only by aparticular enzyme,such as one used exclusively by cancer cells or an infectious virus or bacteria,that enzyme becomes atrigger to turn on Cas9.ProCas9 essentially“senses”the type of cell it’s in based on the protein-cutting enzyme—a so-called protease—present.“This is an extra layer of security you could put on the molecule to ensure accurate cutting,”said David Savage,a UC Berkeley associate professor of molecular and cell biology.It also endows the Cas9 protein with programmable inputs in addition to its programmable outputs.“There are alot of proteases that regulate signaling pathways in cells,transform normal cells into cancer cells,and are involved in pathogen infection,”said Savage.“If we can sense these signals,we can tap into and respond accordingly to these important pathways.”In the study,Savage and his colleagues demonstrated protease control of Cas9 by making it sensitive to both plant and human viruses,such as West Nile Virus.In the future,they believe this sort of technology could be used to import the CRISPR-Cas9 bacterial immune system into plants to help them fend off damaging viral pathogens.The study by researchers from UC Berkeley and the Gladstone Institutes in San Francisco will be published online Jan.10 in the journal Cell. 查看详细>>

A cheap and effective new catalyst developed by researchers at the University of California,Berkeley,can generate hydrogen fuel from water just as efficiently as platinum,currently the best—but also most expensive—water-splitting catalyst out there.The catalyst,which is composed of nanometer-thin sheets of metal carbide,is manufactured using aself-assembly process that relies on asurprising ingredient:gelatin,the material that gives Jell-O its jiggle.“Platinum is expensive,so it would be desirable to find other alternative materials to replace it,”said senior author Liwei Lin,professor of mechanical engineering at UC Berkeley.“We are actually using something similar to the Jell-O that you can eat as the foundation,and mixing it with some of the abundant earth elements to create an inexpensive new material for important catalytic reactions.”The work appears in the Dec.13 print edition of the journal Advanced Materials.A zap of electricity can break apart the strong bonds that tie water molecules together,creating oxygen and hydrogen gas,the latter of which is an extremely valuable source of energy for powering hydrogen fuel cells.Hydrogen gas can also be used to help store energy from renewable yet intermittent energy sources like solar and wind power,which produce excess electricity when the sun shines or when the wind blows,but which go dormant on rainy or calm days.But simply sticking an electrode in aglass of water is an extremely inefficient method of generating hydrogen gas.For the past 20 years,scientists have been searching for catalysts that can speed up this reaction,making it practical for large-scale use.“The traditional way of using water gas to generate hydrogen still dominates in industry.However,this method produces carbon dioxide as byproduct,”said first author Xining Zang,who conducted the research as agraduate student in mechanical engineering at UC Berkeley.“Electrocatalytic hydrogen generation is growing in the past decade,following the global demand to lower emissions.Developing ahighly efficient and low-cost catalyst for electrohydrolysis will bring profound technical,economical and societal benefit.”To create the catalyst,the researchers followed arecipe nearly as simple as making Jell-O from abox.They mixed gelatin and ametal ion—either molybdenum,tungsten or cobalt—with water,and then let the mixture dry.“We believe that as gelatin dries,it self-assembles layer by layer,”Lin said.“The metal ion is carried by the gelatin,so when the gelatin self-assembles,your metal ion is also arranged into these flat layers,and these flat sheets are what give Jell-O its characteristic mirror-like surface.”Heating the mixture to 600 degrees Celsius triggers the metal ion to react with the carbon atoms in the gelatin,forming large,nanometer-thin sheets of metal carbide.The unreacted gelatin burns away.The researchers tested the efficiency of the catalysts by placing them in water and running an electric current through them.When stacked up against each other,molybdenum carbide split water the most efficiently,followed by tungsten carbide and then cobalt carbide,which didn’t form thin layers as well as the other two.Mixing molybdenum ions with asmall amount of cobalt boosted the performance even more. 查看详细>>

UC Berkeley has received a$20 million matching gift from the Hellman Fellows Fund to create The Society of Hellman Fellows,which will double the number of fellowships awarded to early-career faculty each year through the Hellman Fellows Program.Established at UC Berkeley in 1995 by the late F.Warren and Patricia(Chris)Hellman,the Hellman Fellows Program has become an important source of support for Berkeley faculty,creating abridge to tenure for junior faculty who show exceptional academic promise at the start of their careers.Since its inception 23 years ago,384 young faculty from multiple fields have been awarded Hellman Fellowships at Berkeley,and 94 percent of former fellows have gone on to earn tenure,according to numbers from 1995 to 2014.“The Hellman Fellows Program was created to identify promising young assistant professors who,with that extra help in this critical moment of their career,are able to produce the research that then gets them tenure,”says Frances Hellman,dean of the Division of Mathematical and Physical Sciences at Berkeley who,with her three siblings—Patricia Hellman Gibbs,Marco Hellman,and Judith Hellman—made the gift to honor their parents’legacy.Representing the largest single gift from the Hellman Fellows Fund,the$20 million challenge grant provides Berkeley with amajor boost in endowed funds to support the program in perpetuity.Once fully endowed,the Society of Hellman Fellows will award 32 fellowships ayear to exceptional junior faculty in science,technology,engineering and mathematics(STEM);arts and humanities;the social sciences;and Berkeley’s 10 professional schools.Designed for assistant professors who have exhausted start-up funds(generally after year two),the fellowships provide an invaluable lifeline to academic success and range from$30,000 to$60,000—depending on proposed research costs. 查看详细>>

A new alliance between Lawrence Berkeley National Laboratory and UC Berkeley will seek to harness the power of quantum coherence,known popularly as“spooky action at adistance,”to develop avariety of exciting new technologies,from quantum computers to ultra-secure ways to transmit information.Quantum coherence refers to amystifying phenomenon in which two particles can become so“entangled”that changing one will trigger achange in the other—even if the particles are miles or even light-years apart.The goals of the partnership,which has been dubbed Berkeley Quantum,will be to advance the design,fabrication and testing of quantum devices and technologies,and educate the next generation of scientists in the field.“Berkeley Quantum will leverage the core capabilities and strengths of Berkeley Lab and UC Berkeley,and create afocal point for quantum information science and engineering in Berkeley and the broader San Francisco Bay Area tech ecosystem—for industry,academia and national lab researchers,”says Berkeley Lab Deputy Director for Research Horst Simon.Read more at the Lawrence Berkeley National Lab news center 查看详细>>

Scientists are experimenting with narrow strips of graphene,called nanoribbons,in hopes of making cool new electronic devices,but University of California,Berkeley scientists have discovered another possible role for them:as nanoscale electron traps with potential applications in quantum computers.Graphene,a sheet of carbon atoms arranged in arigid,honeycomb lattice resembling chicken wire,has interesting electronic properties of its own.But when scientists cut off astrip less than about 5nanometers in width–less than one ten-thousandth the width of ahuman hair–the graphene nanoribbon takes on new quantum properties,making it apotential alternative to silicon semiconductors.UC Berkeley theoretician Steven Louie,a professor of physics,predicted last year that joining two different types of nanoribbons could yield aunique material,one that immobilizes single electrons at the junction between ribbon segments.In order to accomplish this,however,the electron“topology”of the two nanoribbon pieces must be different.Topology here refers to the shape that propagating electron states adopt as they move quantum mechanically through ananoribbon,a subtle property that had been ignored in graphene nanoribbons until Louie’s prediction.Two of Louie’s colleagues,chemist Felix Fischer and physicist Michael Crommie,became excited by his idea and the potential applications of trapping electrons in nanoribbons and teamed up to test the prediction.Together they were able to experimentally demonstrate that junctions of nanoribbons having the proper topology are occupied by individual localized electrons.A nanoribbon made according to Louie’s recipe with alternating ribbon strips of different widths,forming ananoribbon superlattice,produces aconga line of electrons that interact quantum mechanically.Depending on the strips’distance apart,the new hybrid nanoribbon is either ametal,a semiconductor or achain of qubits,the basic elements of aquantum computer.“This gives us anew way to control the electronic and magnetic properties of graphene nanoribbons,”said Crommie,a UC Berkeley professor of physics.“We spent years changing the properties of nanoribbons using more conventional methods,but playing with their topology gives us apowerful new way to modify the fundamental properties of nanoribbons that we never suspected existed until now.”Using the mathematics of topology Louie’s theory implies that nanoribbons are topological insulators:unusual materials that are insulators,that is,non-conducting in the interior,but metallic conductors along their surface.The 2016 Nobel Prize in Physics was awarded to three scientists who first used the mathematical principles of topology to explain strange,quantum states of matter,now classified as topological materials.Three-dimensional topological insulators conduct electricity along their sides,sheets of 2D topological insulators conduct electricity along their edges,and these new 1D nanoribbon topological insulators have the equivalent of zero-dimensional(0D)metals at their edges,with the caveat that asingle 0D electron at aribbon junction is confined in all directions and can’t move anywhere.If another electron is similarly trapped nearby,however,the two can tunnel along the nanoribbon and meet up via the rules of quantum mechanics.And the spins of adjacent electrons,if spaced just right,should become entangled so that tweaking one affects the others,a feature that is essential for aquantum computer.The synthesis of the hybrid nanoribbons was adifficult feat,said Fischer,a UC Berkeley professor of chemistry.While theoreticians can predict the structure of many topological insulators,that doesn’t mean that they can be synthesized in the real world.“Here you have avery simple recipe for how to create topological states in amaterial that is very accessible,”Fischer said.“It is just organic chemistry.The synthesis is not trivial,granted,but we can do it.This is abreakthrough in that we can now start thinking about how to use this to achieve new,unprecedented electronic structures.”The researchers will report their synthesis,theory and analysis in the Aug.9 issue of the journal Nature.Louie,Fischer and Crommie are also faculty scientists at Lawrence Berkeley National Laboratory. 查看详细>>

Using inexpensive materials,UC Berkeley engineers have fabricated foldable electronic switches and sensors directly onto paper,along with prototype generators,supercapacitors and other electronic devices.They see many potential applications for the new,disposable paper electronics—for example,circuitry to detect heavy metal contamination could be“written”on paper to economically monitor toxins.Research to develop paper electronics has accelerated in the last 10 years.Besides its availability and low cost,paper offers an intriguing potential:simply folding it could switch circuits on and off or otherwise change their activity—a kind of electronic origami.But most efforts to fabricate electrodes onto paper with sufficient conductivity for practical use have employed expensive metals such as gold or silver as the conducting material.This new technology solves that problem by using the inexpensive element molybdenum as the source of the conducting metal.“Many people have been carrying out origami research,forming different architectures and different shapes to perform different functions,”says Liwei Lin,professor of mechanical engineering and senior author of apaper in the journal Advanced Materials reporting the versatile new technology.“We’ve now shown both the practicality of writing versatile conductive patterns on paper,and the durability of folding the electronic paper many hundreds of times for switching circuits on and off.”He hopes the demonstrations can attract attention for use in capacitors and batteries. 查看详细>>