The university occupies 1,232 acres (499 ha) on the eastern side of the San Francisco Bay with the central campus resting on 178 acres (72 ha). Berkeley is the flagship institution of the 10 campus University of California system and one of only two UC campuses operating on a semester calendar, the other being UC Merced.
Established in 1868 as the result of the merger of the private College of California and the public Agricultural, Mining, and Mechanical Arts College in Oakland, Berkeley is the oldest institution in the UC system and offers approximately 350 undergraduate and graduate degree programs in a wide range of disciplines. Berkeley has been charged with providing both “classical” and “practical” education for the state’s people. Berkeley co-manages three United States Department of Energy National Laboratories, including the Los Alamos National Laboratory, Lawrence Livermore National Laboratory and Lawrence Berkeley National Laboratory for the U.S. Department of Energy.
University of California, Berkeley research articles from Innovation Toronto
- Scientists Grow Atomically Thin Transistors and Circuits for Next Generation Electronics – July 16, 2016
- Keep it Simple: Low-Cost Solar Power – June 27, 2016
- Google Gets Practical about the Dangers of AI – June 21, 2016
- Nanomaterial to drive a radical new generation of solar cells – April 21, 2016
- New Microscope Controls Brain Activity of Live Animals – April 6, 2016
- Experiment shows magnetic chips could use one-millionth the amount of energy per operation used by transistors in modern computers – March 13, 2016
- A worldwide seismic warning network using smartphones – February 15, 2016
- Deformed Wing Virus spread manmade and emanates from Europe – February 5, 2016
- Let them see you sweat: What new wearable sensors can reveal from perspiration – February 1, 2016
- Seeing the Big Picture in Photosynthetic Light Harvesting – January 25, 2016
- Will computers ever really understand what we’re saying? – January 14, 2016
- Engineers demo first processor that uses light for ultrafast communications – Photonic-Electronic Microprocessors – December 25, 2015
- CRISPR-Cas9 helps uncover genetics of exotic organisms – December 11, 2015
- Chemists find better way to pack natural gas into fuel tanks – October 27, 2015
- Chip-based technology enables reliable direct detection of Ebola virus – September 28, 2015
- Making 3D Objects Disappear – September 18, 2015
- Artificial ‘plants’ could fuel the future – September 9, 2015
- Self-sweeping laser could dramatically shrink 3D mapping systems – September 4, 2015
- Carbon Dioxide: Another promising approach from problem to product – August 28, 2015
- Small tilt in magnets makes them viable memory chips – August 4, 2015
- Speeding Up Genome Assembly, from Months to Minutes – July 5, 2015
- A Clean Energy Harvest Using Two of the Most Abundant Materials on Earth – June 21, 2015
- Scientists use molecular ‘lock and key’ for potential control of GMOs – June 17, 2015
- Stanford engineers develop state-by-state plan to convert U.S. to 100% clean, renewable energy by 2050 – June 9, 2015
- Recycling nuclear waste – June 1, 2015
- New ‘deep learning’ technique enables robot mastery of skills via trial and error – – May 23, 2015
- Beyond the poppy: a new method of opium production – May 20, 2015
- Drug perks up old muscles and aging brains – May 14, 2015
- Smartphone video microscope automates detection of parasites in blood – May 9, 2015
- Major Advance in Artificial Photosynthesis Poses Win/Win for the Environment – April 17, 2015
- New material captures carbon at half the energy cost – March 15, 2015
- UC Berkeley Unveils First-of-its-Kind, Architectural-Scale, 3D Printed Cement Structure – March 13, 2015
- Better catalysts, made-to-order – February 13, 2015
- Human insights inspire solutions for household robots – February 8, 2015
- Organic electronics could lead to cheap, wearable medical sensors – December 11, 2014
- Synthetic Biology for Space Exploration – November 7, 2014
- A cost-effective and energy-efficient approach to carbon capture – October 10, 2014
- Editing DNA could be genetic medicine breakthrough with ethical concerns – September 8, 2014
- New tool makes a single picture worth a thousand – and more – images – August 18, 2014
- Vision-correcting display makes reading glasses so yesterday – July 30, 2014
- Nanotech Breakthrough Promises Super-Accurate Handheld Bomb Detectors – July 27, 2014
- Scientists test a Nanoparticle “Alarm Clock” to Awaken Immune Systems Put to Sleep by Cancer – July 27, 2014
- Global wildlife decline driving slave labor, organized crime – July 27, 2014
- Blind lead the way in brave new world of tactile technology – July 3, 2014
- ‘Trust hormone’ oxytocin helps old muscle work like new, study finds – June 16, 2014
- Low Power, Longer Distance, Tiny Package: New Laser Sensing Technology for Self-driving Cars, Smartphones and 3-D Video Games – May 30, 2014
- Blocking pain receptors extends lifespan, boosts metabolism in mice – May 25, 2014
- Turkeys inspire smartphone-capable early warning system for toxins
- VIDEO: Engineers create light-activated ‘curtains’
- What’s wrong with Science | Randy Schekman
- University Of California Approves Major Open Access Policy To Make Research Free
- First Dreambox 3D printer vending machine heads to UC Berkeley
- Portland State University students’ invention tops the field at national engineering competition
- “Futurity” service launches to promote university research as traditional science journalism declines
- Artificial Forest for Solar Water-Splitting – Artificial Photosynthesis
- A Leap Forward in Brain-Controlled Computer Cursors
- NASA Kepler Results Usher in a New Era of Astronomy
- Got calcium? Mineral key to restoring acid rain-damaged forests
- Unprecedented genome editing control in flies promises insight into human development, disease
- Shadows and light: Dartmouth researchers develop new software to detect forged photos
- Cool heads likely won’t prevail in a hotter, wetter world
- New app puts idle smartphones to work for science
- A new form of human-machine interfacing
- Pioneering Breakthrough of Chemical Nanoengineering to Design Drugs Controlled by Light
- Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions
- New Filtration Material Could Make Petroleum Refining Cheaper, More Efficient
- Whirlpools on the Nanoscale Could Multiply Magnetic Memory
- Wireless signals could transform brain trauma diagnostics
- Making living matter programmable
- NASA announces new CubeSat space mission candidates
- Discovery opens the door to regenerative potential – a potential ‘molecular fountain of youth’
- The World’s New Second Fastest Robot Is A Tiny Cardboard Cockroach
- Fitting ‘smart’ mobile phone with magnifying optics creates ‘real’ cell phone
- Synthetic molecule stores solar energy for an all-in-one-system
- Invisibility Cloaking to Shield Floating Objects from Waves
- Sweet diesel! Discovery resurrects process to convert sugar directly to diesel
- Tech’s New Wave, Driven by Data
- Could a ‘Defensive Patent License’ Fix the U.S. Patent System?
- Hackers backdoor the human brain, successfully extract sensitive data
- I-Corps: Startups with a difference
- Chemical makes blind mice see
- Opening the Door to More Widespread Solar Energy Devices
- Is Earth Nearing an Environmental “Tipping Point”?
- How Big Data Gets Real
- Freecycling Has Viral Effect On Community Spirit and Generosity
- Computing experts unveil superefficient ‘inexact’ chip
- The Unknown Inventor Whose Work Is Saving The Developing World
- Golden Potential for Gold Thin Films
- Workhorse Climate Satellite Goes Silent
- Solar Cell That Also Shines
- Responding to the Radiation Threat
- Breakthrough in designing cheaper, more efficient catalysts for fuel cells
- Scientists Decode Brain Waves to Eavesdrop On What We Hear
- Can Bacteria Produce “Drop-In” Biofuels?
- Open-source project intends to advance robotic surgery
- Academic Earth
- Leaping Lizards and Dinosaurs Inspire Robot Design
- Artificial intelligence: Luddite legacy
- Scientists reconstruct visual stimuli by reading brain activity
- Bioengineers Reprogram Muscles to Combat Degeneration
- The Best and the Brightest
- The First Fully Stretchable OLED
- Hybrid Solar System Makes Rooftop Hydrogen
- Whales and Fish Adapt to Climate-Induced Changes in the Pacific Ocean
- Citizen Scientists and Social Media Aim to Help Prevent Frog Extinctions
- Graphene Optical Modulators Could Lead to Ultrafast Communications
- Scientists Discover the Edge States of Graphene Nanoribbons
- Ultrapowerful Optical Microscopy and Invisibility Carpet-Cloaking Devices
- Ant Harm: Can Genetic Weapons Roll Back the Expansion of Argentine Ant Supercolonies?
- Major Advance in MRI Allows Much Faster Brain Scans
- New yeast strain produces ethanol more efficiently
- Nanoscale lasers continue to shrink, heralding new era in optical science
- Forging a Hot Link to the Farmer Who Grows the Food
- Fewer feet, smaller footprint
- Beneficial Biofuels: Leading National Experts Reach Consensus
- Dynamic Eye sunglasses use moving LCD spot to reduce glare
- Ultrathin Alternative to Silicon for Future Electronics
- Artificial pressure-sensitive skin created from nanowires
- Volunteers’ Idle Computer Time Turns Up a Celestial Oddball
- Innovate, Yes, but Make It Practical
- Nickel and selenium could be used for cheaper, more efficient solar cells
- Strongest Magnetic Field in a Lab
- The future of refrigeration could be magnetic
- Scientists Devise New “Benign by Design” Drugs, Paints, Pesticides and More
- Inexpensive metal catalyst discovered for electrolytic production of hydrogen from water
- The Rise of the Fleet-Footed Start-Up
- MIT Top 10 Technologies Likely to Change the World
- Designer Nanomaterials on Demand: Scientists Report Universal Method for Creating Nanoscale Composites
- New Fiber Nanogenerators Could Lead to Electric Clothing
- Bacteria Transformed into Biofuel Refineries
- Cell Phones Become Handheld Tools For Global Development
- Far From a Lab? Turn a Cellphone Into a Microscope
- Now, an Invention Inventors Will Like
- ‘Invisibility Cloak’ Successfully Hides Objects Placed Under It
- Invisibility cloak ‘step closer’
A new study from UC Berkeley found that tissue health and repair dramatically decline in young mice when half of their blood is replaced with blood from old mice.
“Our study suggests that young blood by itself will not work as effective medicine,” said Irina Conboy, associate professor in the Department of Bioengineering at UC Berkeley. “It’s more accurate to say that there are inhibitors in old blood that we need to target to reverse aging.”
The study was published today in the journal Nature Communications. The research was supported by funding from the National Institutes of Health, SENS Research Foundation, Rogers’ Family and Calico.
In 2005, Conboy and colleagues published a study in Nature that found evidence for tissue rejuvenation in older mice when they are surgically joined to younger mice so that blood is exchanged between the two. Despite remaining questions about the mechanism underlying this rejuvenation, media coverage of the study fixated on the potential of young blood to reverse the aging process, and on comparisons to vampires, which was not the takeaway from the study, Conboy said. In the years since the 2005 study, scientists have spent millions to investigate the potential medical properties of youthful blood with enterprises emerging to infuse old people with young blood.
“What we showed in 2005 was evidence that aging is reversible and is not set in stone,” Conboy said. “Under no circumstances were we saying that infusions of young blood into elderly is medicine.”
Blood exchange in humans is FDA-approved for a few devastating illnesses (auto-immunity, for example, where self-reacting antibodies are removed), but high volume or repeated additions of blood or its components to genetically different people is known to have side effects of immune rejection, leading to organ failure.
While the experimental model used in the 2005 study found evidence that some aspects of aging may be reversed, the techniques used in the study do not allow scientists to precisely control the exchange of blood, which is necessary to dig deeper into blood’s effect on aging.
When two mice are sutured together, a technique called parabiosis, blood is not the only thing that is exchanged in this setup; organs are also shared, so old mice get access to younger lungs, thymus-immune system, heart, liver and kidneys. In surgical suturing it takes weeks to a month for the effects of blood to take place and the precise timing is not actually known. Nor is the precise amount of the exchanged blood.
In the new study, Conboy and colleagues developed an experimental technique to exchange blood between mice without joining them so that scientists can control blood circulation and conduct precise measurements on how old mice respond to young blood, and vice versa. In the new system, mice are connected and disconnected at will, removing the influence of shared organs or of any adaptation to being joined. One of the more surprising discoveries of this study was the very quick onset of the effects of blood on the health and repair of multiple tissues, including muscle, liver and brain. The effects were seen around 24 hours after exchange.
With the new experimental setup, the research team repeated the experiments from 2005. In each test, blood was exchanged between an old mouse and a young mouse until each mouse had half its blood from the other. The researchers then tested various indicators of aging in each mouse, such as liver cell growth as well as liver fibrosis and adiposity (fat), brain cell development in the region that is needed for learning and memory, muscle strength and muscle tissue repair. In many of these experiments, older mice that received younger blood saw either slight or no significant improvements compared to old mice with old blood. Young mice that received older blood, however, saw large declines in most of these tissues or organs.
The most telling data was found when researchers tested blood’s impact on new neuron production in the area of the brain where memory and learning are formed. In these experiments, older mice showed no significant improvement in brain neuron stem cells after receiving younger blood, but younger mice that received older blood saw a more than twofold drop in brain cell development compared to normal young mice. The researchers think that many benefits seen in old mice after receiving young blood might be due to the young blood diluting the concentration of inhibitors in the old blood.
“Under no circumstances did young blood improve brain neurogenesis in our experiments,” Conboy said. “Old blood appears to have inhibitors of brain cell health and growth, which we need to identify and remove if we want to improve memory.”
The research team has begun to investigate specific molecules in old blood that might cause inhibition of cell development, but future experiments are needed for a clear picture of why young animals are worse off with old blood.
Plant biologists have bumped up crop productivity by increasing the expression of genes that result in more efficient use of light in photosynthesis, a finding that could be used to help address the world’s future food needs.
Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California, Berkeley (UC Berkeley), and the University of Illinois targeted three genes involved in a process plants use to protect themselves from damage when they get more light than they can safely use. By increasing the expression of those genes, the scientists saw increases of 14-20 percent in the productivity of modified tobacco plants in field experiments.
The researchers described their findings in a paper published today in the journal Science.
“Tobacco was used as the model crop plant in this study because it is easy to work with, but we’re working to make the same modifications in rice and other food crops,” said co-senior author Krishna Niyogi, a faculty scientist in Berkeley Lab’s Division of Molecular Biophysics and Integrative Bioimaging. “The molecular processes we’re modifying are fundamental to plants that carry out photosynthesis, so we hope to see a similar increase in yield in other crops.”
Niyogi, who is a Howard Hughes Medical Institute investigator and a UC Berkeley professor of plant and microbial biology, teamed up with Stephen Long, a plant biology and crop sciences professor at the University of Illinois, for the study.
In photosynthesis, plants use the energy in sunlight to take up carbon dioxide from the atmosphere and convert it into biomass, which we use for food, fuel, and fiber. When there is too much sunlight, the photosynthetic machinery in chloroplasts can be damaged, so plants need photoprotection. Inside chloroplasts, plants have a system called NPQ, or nonphotochemical quenching, for this purpose.
Niyogi compared NPQ to a pressure relief valve in a steam engine.
“When there is too much sunlight, it’s like pressure building up,” said Niyogi. “NPQ turns on and gets rid of the excess energy safely. In the shade, the pressure in the engine decreases. NPQ turns off, but not quickly enough. It’s like having a leak in the system with the valve left open. The photosynthetic engine can’t work as efficiently.”
The highly variable levels of light plants receive, particularly in densely planted crop fields, presents a challenge to the efficient use of solar energy. Plants must adapt to intermittent shading from leaves that are higher in the canopy, or from passing clouds.
Niyogi and his postdoctoral research associates Lauriebeth Leonelli, Stéphane Gabilly, and Masakazu Iwai figured out a way to speed up recovery from photoprotection and demonstrated a proof of this concept in the laboratory. They used a new method to rapidly test gene expression in tobacco leaves. By boosting the expression of three genes involved in NPQ, they showed that NPQ turned off more quickly, and the efficiency of photosynthesis in the shade was higher.
Half of crop photosynthesis occurs in the shade, so any improvement in speeding up recovery from photoprotection could have a big benefit, the researchers said.
Illinois postdoctoral researchers Johannes Kromdijk and Katarzyna Glowacka took the trio of genes studied at Berkeley and put them into tobacco plants for further testing in greenhouse and field experiments.
The work to boost crop productivity comes as concerns about food shortages rise with the world’s population. The Food and Agriculture Organization of the United Nations estimates that food production will need to nearly double by 2050 to meet increasing demand. Yields of the world’s major staple crops have not been increasing fast enough to meet this projected need.
“My attitude is that it is very important to have these new technologies on the shelf now because it can take 20 years before such inventions can reach farmer’s fields,” said Long. “If we don’t do it now, we won’t have this solution when we need it.”
Solar cells made from an inexpensive and increasingly popular material called perovskite can more efficiently turn sunlight into electricity using a new technique to sandwich two types of perovskite into a single photovoltaic cell.
Perovskite solar cells are made of a mix of organic molecules and inorganic elements that together capture light and convert it into electricity, just like today’s more common silicon-based solar cells. Perovskite photovoltaic devices, however, can be made more easily and cheaply than silicon and on a flexible rather than rigid substrate. The first perovskite solar cells could go on the market next year, and some have been reported to capture 20 percent of the sun’s energy.
In a paper appearing online today in advance of publication in the journal Nature Materials, University of California, Berkeley, and Lawrence Berkeley National Laboratory scientists report a new design that already achieves an average steady-state efficiency of 18.4 percent, with a high of 21.7 percent and a peak efficiency of 26 percent.
“We have set the record now for different parameters of perovskite solar cells, including the efficiency,” said senior author Alex Zettl, a UC Berkeley professor of physics, senior faculty member at Berkeley Lab and member of the Kavli Energy Nanosciences Institute. “The efficiency is higher than any other perovskite cell – 21.7 percent – which is a phenomenal number, considering we are at the beginning of optimizing this.”
“This has a great potential to be the cheapest photovoltaic on the market, plugging into any home solar system,” said Onur Ergen, the lead author of the paper and a UC Berkeley physics graduate student.
The efficiency is also better than the 10-20 percent efficiency of polycrystalline silicon solar cells used to power most electronic devices and homes. Even the purest silicon solar cells, which are extremely expensive to produce, topped out at about 25 percent efficiency more than a decade ago.
The achievement comes thanks to a new way to combine two perovskite solar cell materials – each tuned to absorb a different wavelength or color of sunlight – into one “graded bandgap” solar cell that absorbs nearly the entire spectrum of visible light. Previous attempts to merge two perovskite materials have failed because the materials degrade one another’s electronic performance.
“This is realizing a graded bandgap solar cell in a relatively easy-to-control and easy-to-manipulate system,” Zettl said. “The nice thing about this is that it combines two very valuable features – the graded bandgap, a known approach, with perovskite, a relatively new but known material with surprisingly high efficiencies – to get the best of both worlds.”
Full-spectrum solar cells
Materials like silicon and perovskite are semiconductors, which means they conduct electricity only if the electrons can absorb enough energy – from a photon of light, for example – to kick them over a forbidden energy gap or bandgap. These materials preferentially absorb light at specific energies or wavelengths – the bandgap energy – but inefficiently at other wavelengths.
“In this case, we are swiping the entire solar spectrum from infrared through the entire visible spectrum,” Ergen said. “Our theoretical efficiency calculations should be much, much higher and easier to reach than for single-bandgap solar cells because we can maximize coverage of the solar spectrum.”
The key to mating the two materials into a tandem solar cell is a single-atom thick layer of hexagonal boron nitride, which looks like a layer of chicken wire separating the perovskite layers from one other. In this case, the perovskite materials are made of the organic molecules methyl and ammonia, but one contains the metals tin and iodine, while the other contains lead and iodine doped with bromine. The former is tuned to preferentially absorb light with an energy of 1 electron volt (eV) – infrared, or heat energy – while the latter absorbs photons of energy 2 eV, or an amber color.
The monolayer of boron nitride allows the two perovskite materials to work together and make electricity from light across the whole range of colors between 1 and 2 eV.
The perovskite/boron nitride sandwich is placed atop a lightweight aerogel of graphene that promotes the growth of finer-grained perovskite crystals, serves as a moisture barrier and helps stabilize charge transport though the solar cell, Zettl said. Moisture makes perovskite fall apart.
The whole thing is capped at the bottom with a gold electrode and at the top by a gallium nitride layer that collects the electrons that are generated within the cell. The active layer of the thin-film solar cell is about 400 nanometers thick.
“Our architecture is a bit like building a quality automobile roadway,” Zettl said. “The graphene aerogel acts like the firm, crushed rock bottom layer or foundation, the two perovskite layers are like finer gravel and sand layers deposited on top of that, with the hexagonal boron nitride layer acting like a thin-sheet membrane between the gravel and sand that keeps the sand from diffusing into or mixing too much with the finer gravel. The gallium nitride layer serves as the top asphalt layer.”
It is possible to add even more layers of perovskite separated by hexagonal boron nitride, though this may not be necessary, given the broad-spectrum efficiency they’ve already obtained, the researchers said.
“People have had this idea of easy-to-make, roll-to-roll photovoltaics, where you pull plastic off a roll, spray on the solar material, and roll it back up,” Zettl said. “With this new material, we are in the regime of roll-to-roll mass production; it’s really almost like spray painting.”
Molecular sized machines could in the future be used to control important mechanisms in the body.
In a recent study, researchers at University of California, Berkeley and Umeå University show how a nanoballoon comprising a single carbon molecule ten thousand times thinner than a human hair can be controlled electrostatically to switch between an inflated and a collapsed state.
Inﬂatable balloon actuators are commonly used for macroscopic applications to lift buildings, as impact protection in cars or to widen narrowed or obstructed arteries or veins. At the micro scale they are used as micro pumps and in nature jumping spiders create microformat fluid-filled cushions to power their legs in explosive jumps.
Interestingly, at the nanoscale, balloon actuators are virtually unknown. However, a few years ago researchers at the Penn State University theoretically proposed a charge controlled nanoballoon actuator based on the collapsing and reinﬂation of a carbon nanotube.
Now, this has been realized experimentally by Hamid Reza Barzegar and his colleagues. In a study published in the journal of Nano Letters they show how a carbon nanotube, which can be visualized as a cylindrical tube of carbon atoms, can be controlled to transform from a collapsed to an inflated state and vice versa by applying a small voltage. The defect-free nature of carbon nanotubes imply that such an actuator would be able to work without wear or fatigue. This is also shown by the researchers who run the actuator over several cycles with no signs of loss in performance.
“The work is conceptually interesting and gives insight into the complexity of how to control motion at the nanoscale by external stimuli” says Hamid Reza Barzegar, doctor of Physics at Umeå University, now working at UC Berkeley in professor Alex Zettl’s research group. “It also gives insight into fundamental physics such as how the capacitance effect and in general the electrostatic forces can be used to control the dynamics of molecular structures.”
“In a longer perspective one can also envision how our findings could be used for pneumatic control on molecular level or for designing molecular containers that can open or close by controlling the surface charges of the molecules, by for example tuning the pH of the solution in which the molecules are dispersed. This could for example be of use for medical applications such as for delivering medicine to internal organs or tumors” says Thomas Wågberg, associate professor of Physics at Umeå University.
The discovery of molecular machines was awarded this year’s Nobel prize in Chemistry. Jean-Pierre Sauvage, Fraser Stoddart and Bernard L Feringa got the prize for having developed molecules with controllable movements, which can perform a task when energy is added.
A team of physicians and laboratory scientists has taken a key step toward a cure for sickle cell disease, using CRISPR-Cas9 gene editing to fix the mutated gene responsible for the disease in stem cells from the blood of affected patients.
For the first time, they have corrected the mutation in a proportion of stem cells that is high enough to produce a substantial benefit in sickle cell patients.
The researchers from UC Berkeley, UC San Francisco Benioff Children’s Hospital Oakland Research Institute (CHORI) and the University of Utah School of Medicine hope to re-infuse patients with the edited stem cells and alleviate symptoms of the disease, which primarily afflicts those of African descent and leads to anemia, painful blood blockages and early death.
“We’re very excited about the promise of this technology,” said Jacob Corn, a senior author on the study and scientific director of the Innovative Genomics Initiative at UC Berkeley. “There is still a lot of work to be done before this approach might be used in the clinic, but we’re hopeful that it will pave the way for new kinds of treatment for patients with sickle cell disease.”
In tests in mice, the genetically engineered stem cells stuck around for at least four months after transplantation, an important benchmark to ensure that any potential therapy would be lasting.
“This is an important advance because for the first time we show a level of correction in stem cells that should be sufficient for a clinical benefit in persons with sickle cell anemia,” said co-author Mark Walters, a pediatric hematologist and oncologist and director of UCSF Benioff Oakland’s Blood and Marrow Transplantation Program.
The results were reported in the Oct. 12 issue of the online journal Science Translational Medicine.
Sickle cell disease is a recessive genetic disorder caused by a single mutation in both copies of a gene coding for beta-globin, a protein that forms part of the oxygen-carrying molecule hemoglobin. This homozygous defect causes hemoglobin molecules to stick together, deforming red blood cells into a characteristic “sickle” shape. These misshapen cells get stuck in blood vessels, causing blockages, anemia, pain, organ failure and significantly shortened lifespan. Sickle cell disease is particularly prevalent in African Americans and the sub-Saharan African population, affecting hundreds of thousands of people worldwide.
The goal of the multi-institutional team is to develop genome engineering-based methods for correcting the disease-causing mutation in each patient’s own stem cells to ensure that new red blood cells are healthy.
The team used CRISPR-Cas9 to correct the disease-causing mutation in hematopoietic stem cells — precursor cells that mature into red blood cells — isolated from whole blood of sickle cell patients. The corrected cells produced healthy hemoglobin, which mutated cells do not make at all.
Future pre-clinical work will require additional optimization, large-scale mouse studies and rigorous safety analysis, the researchers emphasize. Corn and his lab have joined with Walters, an expert in developing curative treatments such as bone marrow transplant and gene therapy for sickle cell disease, to initiate an early-phase clinical trial to test this new treatment within the next five years.
Notably, research groups might be able to apply the approach described in this study to develop treatments for other blood diseases such as ?-thalassemia, severe combined immunodeficiency (SCID), chronic granulomatous disease, rare disorders like Wiskott-Aldrich syndrome and Fanconi anemia, and even HIV infection.
“Sickle cell disease is just one of many blood disorders caused by a single mutation in the genome,” Corn said. “It’s very possible that other researchers and clinicians could use this type of gene editing to explore ways to cure a large number of diseases.”
“There is a clear path for developing therapies for certain diseases,” said co-senior author Dana Carroll of the University of Utah, who co-developed one of the first genome editing techniques over a decade ago. “It’s very gratifying to see gene editing technology being brought to practical applications.”
The work is the fruit of the Innovative Genomics Initiative, a joint effort between UC Berkeley and UCSF that aims to correct DNA mutations that underlie human disease using CRISPR-Cas9, a pioneering technology co-developed by scientists at UC Berkeley that has made genome editing easier and more efficient than ever before.
The project also leverages the expertise of physicians and scientists at UCSF Benioff Children’s Hospital Oakland, a major center for research and treatment of sickle cell disease, and Carroll’s expertise in the field of genome engineering.
In addition to Corn, Walters and Carroll, other co-authors are Mark DeWitt, Nicolas Bray, Tianjiao Wang and Therese Mitros of UC Berkeley; Wendy Magis, Seok-Jin Heo, Denise Muñoz, Dario Boffelli and David Martin of CHORI; Jennifer Berman of Bio-Rad Laboratories in Pleasanton, California; and Fabrizia Urbinati and Donald Kohn of UCLA.
The research is supported by the National Institutes of Health, the Li Ka Shing Foundation, the Siebel Scholars Fund, the Jordan Family Fund and the Doris Duke Charitable Foundation.
University of California, Berkeley engineers have built the first dust-sized, wireless sensors that can be implanted in the body, bringing closer the day when a Fitbit-like device could monitor internal nerves, muscles or organs in real time.
Because these batteryless sensors could also be used to stimulate nerves and muscles, the technology also opens the door to “electroceuticals” to treat disorders such as epilepsy or to stimulate the immune system or tamp down inflammation.
The so-called neural dust, which the team implanted in the muscles and peripheral nerves of rats, is unique in that ultrasound is used both to power and read out the measurements. Ultrasound technology is already well-developed for hospital use, and ultrasound vibrations can penetrate nearly anywhere in the body, unlike radio waves, the researchers say.
“I think the long-term prospects for neural dust are not only within nerves and the brain, but much broader,“ said Michel Maharbiz, an associate professor of electrical engineering and computer sciences and one of the study’s two main authors. “Having access to in-body telemetry has never been possible because there has been no way to put something supertiny superdeep. But now I can take a speck of nothing and park it next to a nerve or organ, your GI tract or a muscle, and read out the data.“
Maharbiz, neuroscientist Jose Carmena, a professor of electrical engineering and computer sciences and a member of the Helen Wills Neuroscience Institute, and their colleagues will report their findings in the August 3 issue of the journal Neuron.
The sensors, which the researchers have already shrunk to a 1 millimeter cube – about the size of a large grain of sand – contain a piezoelectric crystal that converts ultrasound vibrations from outside the body into electricity to power a tiny, on-board transistor that is in contact with a nerve or muscle fiber. A voltage spike in the fiber alters the circuit and the vibration of the crystal, which changes the echo detected by the ultrasound receiver, typically the same device that generates the vibrations. The slight change, called backscatter, allows them to determine the voltage.
Motes sprinkled thoughout the body
In their experiment, the UC Berkeley team powered up the passive sensors every 100 microseconds with six 540-nanosecond ultrasound pulses, which gave them a continual, real-time readout. They coated the first-generation motes – 3 millimeters long, 1 millimeter high and 4/5 millimeter thick – with surgical-grade epoxy, but they are currently building motes from biocompatible thin films which would potentially last in the body without degradation for a decade or more.
While the experiments so far have involved the peripheral nervous system and muscles, the neural dust motes could work equally well in the central nervous system and brain to control prosthetics, the researchers say. Today’s implantable electrodes degrade within 1 to 2 years, and all connect to wires that pass through holes in the skull. Wireless sensors – dozens to a hundred – could be sealed in, avoiding infection and unwanted movement of the electrodes.
“The original goal of the neural dust project was to imagine the next generation of brain-machine interfaces, and to make it a viable clinical technology,” said neuroscience graduate student Ryan Neely. “If a paraplegic wants to control a computer or a robotic arm, you would just implant this electrode in the brain and it would last essentially a lifetime.”
In a paper published online in 2013, the researchers estimated that they could shrink the sensors down to a cube 50 microns on a side – about 2 thousandths of an inch, or half the width of a human hair. At that size, the motes could nestle up to just a few nerve axons and continually record their electrical activity.
“The beauty is that now, the sensors are small enough to have a good application in the peripheral nervous system, for bladder control or appetite suppression, for example,“ Carmena said. “The technology is not really there yet to get to the 50-micron target size, which we would need for the brain and central nervous system. Once it’s clinically proven, however, neural dust will just replace wire electrodes. This time, once you close up the brain, you’re done.“
The team is working now to miniaturize the device further, find more biocompatible materials and improve the surface transceiver that sends and receives the ultrasounds, ideally using beam-steering technology to focus the sounds waves on individual motes. They are now building little backpacks for rats to hold the ultrasound transceiver that will record data from implanted motes.
They’re also working to expand the motes’ ability to detect non-electrical signals, such as oxygen or hormone levels.
“The vision is to implant these neural dust motes anywhere in the body, and have a patch over the implanted site send ultrasonic waves to wake up and receive necessary information from the motes for the desired therapy you want,” said Dongjin Seo, a graduate student in electrical engineering and computer sciences. “Eventually you would use multiple implants and one patch that would ping each implant individually, or all simultaneously.”
Ultrasound vs radio
Maharbiz and Carmena conceived of the idea of neural dust about five years ago, but attempts to power an implantable device and read out the data using radio waves were disappointing. Radio attenuates very quickly with distance in tissue, so communicating with devices deep in the body would be difficult without using potentially damaging high-intensity radiation.
Marharbiz hit on the idea of ultrasound, and in 2013 published a paper with Carmena, Seo and their colleagues describing how such a system might work. “Our first study demonstrated that the fundamental physics of ultrasound allowed for very, very small implants that could record and communicate neural data,” said Maharbiz. He and his students have now created that system.
“Ultrasound is much more efficient when you are targeting devices that are on the millimeter scale or smaller and that are embedded deep in the body,” Seo said. “You can get a lot of power into it and a lot more efficient transfer of energy and communication when using ultrasound as opposed to electromagnetic waves, which has been the go-to method for wirelessly transmitting power to miniature implants”
“Now that you have a reliable, minimally invasive neural pickup in your body, the technology could become the driver for a whole gamut of applications, things that today don’t even exist,“ Carmena said.
In an advance that helps pave the way for next-generation electronics and computing technologies—and possibly paper-thin gadgets —scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) developed a way to chemically assemble transistors and circuits that are only a few atoms thick.
What’s more, their method yields functional structures at a scale large enough to begin thinking about real-world applications and commercial scalability.
They report their research online July 11 in the journal Nature Nanotechnology.
The scientists controlled the synthesis of a transistor in which narrow channels were etched onto conducting graphene, and a semiconducting material called a transition-metal dichalcogenide, or TMDC, was seeded in the blank channels. Both of these materials are single-layered crystals and atomically thin, so the two-part assembly yielded electronic structures that are essentially two-dimensional. In addition, the synthesis is able to cover an area a few centimeters long and a few millimeters wide.
“This is a big step toward a scalable and repeatable way to build atomically thin electronics or pack more computing power in a smaller area,” says Xiang Zhang, a senior scientist in Berkeley Lab’s Materials Sciences Division who led the study.
A simplified architecture leads to efficiencies rivaling conventional silicon solar cells.
A new architecture takes very few processing steps to produce an affordable solar cell with efficiencies comparable to conventional silicon solar cells. This new architecture uses alternative, transparent materials that can be deposited at room temperature, eliminating the need for high temperature chemical doping—the process currently used to increase the electrical conductivity of key surfaces in solar cells.
Proving that this simple design can lead to high conversion efficiencies, turning sunlight into electricity, makes it a useful tool to lower costs and improve performance of a wide range of solar cell designs. Additionally, this simple process could be extended to improve contacts in semiconductor transistors used to speed today’s computers.
The company lays out five unsolved challenges that need to be addressed if smart machines such as domestic robots are to be safe.
Could machines become so intelligent and powerful they pose a threat to human life, or even humanity as a whole?
It’s a question that has become fashionable in some parts of Silicon Valley in recent years, despite being more or less irreconcilable with the simple robots and glitchy virtual assistants of today (see “AI Doomsayer Says His Ideas Are Catching On”). Some experts in artificial intelligence believe speculation about the dangers of future, super-intelligent software is harming the field.
Now Google, a company heavily invested in artificial intelligence, is trying to carve out a middle way. A new paper released today describes five problems that researchers should investigate to help make future smart software safer. In a blog post on the paper, Google researcher Chris Olah says they show how the debate over AI safety can be made more concrete and productive.
“Most previous discussion has been very hypothetical and speculative,” he writes. “We believe it’s essential to ground concerns in real machine-learning research, and to start developing practical approaches for engineering AI systems that operate safely and reliably.”
Physicists have discovered radical new properties in a nanomaterial, opening new possibilities for highly efficient thermophotovoltaic cells that could one day harvest heat in the dark and turn it into electricity.
The research team from ANU/ARC Centre of Excellence CUDOS and the University of California Berkeley demonstrated a new artificial material, or metamaterial, that glows in an unusual way when heated.
The findings could drive a revolution in the development of cells which convert radiated heat into electricity, known as thermophotovoltaic cells.
“Thermophotovoltaic cells have the potential to be much more efficient than solar cells,” said Dr Sergey Kruk from the ANU Research School of Physics and Engineering.
“Our metamaterial overcomes several obstacles and could help to unlock the potential of thermophotovoltaic cells.”
Thermophotovoltaic cells have been predicted to be more than twice as efficient as conventional solar cells. They do not need direct sunlight to generate electricity, and instead can harvest heat from their surroundings in the form of infrared radiation.
They can also be combined with a burner to produce on-demand power or can recycle heat radiated by hot engines.
The team’s metamaterial, made of tiny nanoscopic structures of gold and magnesium fluoride, radiates heat in specific directions.
The geometry of the metamaterial can also be tweaked to give off radiation in specific spectral range, in contrast to standard materials that emit their heat in all directions as a broad range of infrared wavelengths. This makes the new material ideal for use as an emitter paired with a thermophotovoltaic cell.
The project started when Dr Kruk predicted the new metamaterial would have these surprising properties. The ANU team then worked with scientists at the University of California Berkeley, who have unique expertise in manufacturing such materials.
“To fabricate this material the Berkeley team were operating at the cutting edge of technological possibilities,” Dr Kruk said.
“The size of an individual building block of the metamaterial is so small that we could fit more than 12,000 of them on the cross-section of a human hair.”
The research is published in Nature Communications.
The key to the metamaterial’s remarkable behaviour is its novel physical property, known as magnetic hyperbolic dispersion.
Dispersion describes the interactions of light with materials and can be visualised as a three-dimensional surface representing how electromagnetic radiation propagates in different directions. For natural materials, such as glass or crystals the dispersion surfaces have simple forms, spherical or ellipsoidal.
The dispersion of the new metamaterial is drastically different and is hyperbolic in form. This arises from the material’s remarkably strong interactions with the magnetic component of light.
The efficiency of thermophotovoltaic cells based on the metamaterial can be further improved if the emitter and the receiver have just a nanoscopic gap between them. In this configuration, radiative heat transfer between them can be more than ten times more efficient than between conventional materials.
Device shown capable of reading and writing neural signals at the spatial and temporal scale of natural brain activity, could eventually serve as “Rosetta Stone” to crack the code on how brains work
For the first time, researchers have developed a microscope capable of observing—and manipulating—neural activity in the brains of live animals at the scale of a single cell with millisecond precision. By allowing scientists to directly control the firing of individual neurons within complex brain circuits, the device could ultimately revolutionize how neuroscience is done and lead to new insights about healthy brain functioning and neurological disorders.
“With this new microscope, we believe we will soon be able to treat the brain as the keyboard of a piano, so to speak, and write in a sequence of activity that is needed to understand or correct brain function,” said Hillel Adesnik, Ph.D., assistant professor of neurobiology at the University of California, Berkeley, who led the research team. “After more refinements, this instrument may be able to function as a sort of Rosetta Stone to help us crack the neural code.”
Adesnik will present this research at the American Association of Anatomists Annual Meeting duringExperimental Biology 2016. He has been awarded the American Association of Anatomists 2016 C.J. Herrick Award in Neuroanatomy.
To process inputs, store information and issue commands, the brain’s neurons communicate with each other through on-off electrical signals akin to the ones and zeroes used to encode information in computer programming. Although scientists have long been able to observe these signals with various imaging techniques, without understanding the “syntax” of how that digital code translates into information, the brain’s communication system has been essentially indecipherable.
“If you want to learn a language, you need a dictionary, and if you want to understand how a machine works, you need to know its parts,” said Adesnik. “We wanted to develop a technology that can offer a general approach to understand the basic syntax of neural signals, so that we can begin to understand what a given brain circuit is doing and perhaps what’s gone wrong with that in the case of a disease.”
The best way to learn that syntax, Adesnik said, is to not simply read the information, but to actually write it by making small tweaks in the code, inputting the new code back into the brain and seeing how it alters a perception or behavior. The new microscope, which Adesnik’s team developed by combining and building upon several existing technologies developed by other researchers, is the first to be able to handle and transmit information at a spatial and temporal scale that is truly relevant to manipulating brain activity.
“The brain is an enormous collection of single cells, and cells right next to each other could be doing entirely different things,” Adesnik said. “The resolution of our technique is key, because if you aren’t looking at a single cell you could be scrambling your code, so to speak, and you won’t be able to correctly interpret it. By overcoming the last technological hurdles to get to that single cell resolution, and at the same time getting to the temporal scale that cells operate at, we have developed a prototype microscope that achieves the level of detail needed to actually understand the neural code.”
The tool they have devised is essentially a microscope that points into the brain of a live mouse, zooms in on a few thousand cells and uses sophisticated lasers to manipulate electrical signals between individual neurons.
Since the lasers can penetrate brain tissue but not skull, the research team implanted small glass windows into the skulls of the mice used to test the instrument. When positioned atop the window, the microscope uses two different types of high-powered infrared lasers to create a 3-dimensional holographic pattern in a specific area of interest within the brain. Because the research is done in mice genetically modified to have neurons that respond to light—a technique called optogenetics—the hologram induces the neurons to send electrical signals in a specific pattern that is pre-determined by the researchers.
“We’re adapting holographic display technology, optogenetics and sensory biology and behavior into one complete system that allows an all-optical approach to image and manipulate the nervous system,” said Adesnik. “We’ve essentially put a lot of disparate existing pieces together to achieve something nobody had yet achieved.”
So far, the team has conducted preliminary tests of the instrument by mapping the effects of small perturbations, such as wiggling a whisker, and then creating holograms that induce the neurons to fire in the same—or slightly different—patterns. In a series of tests that are still underway, they are working with mice trained to push a specific lever when they see a certain shape in order to develop holograms that “trick” the mouse into seeing, for example, a circle where none exists, or to make the mouse perceive a square as a circle. In the near future, the team hopes to apply the microscope to studies of memory formation.
Once it is further tested and refined, the most immediate applications for the microscope are likely to be in basic research, but Adesnik said it is conceivable that its core technology could one day be adapted for therapeutic use, for example, to correct neurological problems in a high-tech form of brain surgery. Such an application is still a long way off, however, and applying the device in human beings would require overcoming a whole new set of technological challenges.