Tag Archives: University of California

How To Create Speech From Brain Signals

“In my head, I churn over every sentence ten times, delete a word, add an adjective, and learn my text by heart, paragraph by paragraph,” wrote Jean-Dominique Bauby in his memoir, “The Diving Bell and the Butterfly.” In the book, Mr. Bauby, a journalist and editor, recalled his life before and after a paralyzing stroke that left him virtually unable to move a muscle; he tapped out the book letter by letter, by blinking an eyelid.

Thousands of people are reduced to similarly painstaking means of communication as a result of injuries suffered in accidents or combat, of strokes, or of neurodegenerative disorders such as amyotrophic lateral sclerosis, or A.L.S., that disable the ability to speak.

Now, scientists are reporting that they have developed a virtual prosthetic voice, a system that decodes the brain’s vocal intentions and translates them into mostly understandable speech, with no need to move a muscle, even those in the mouth. (The physicist and author Stephen Hawking used a muscle in his cheek to type keyboardcharacters, which a computer synthesized into speech.)

It’s formidable work, and it moves us up another level toward restoring speech” by decoding brain signals, said Dr. Anthony Ritaccio, a neurologist and neuroscientist at the Mayo Clinic in Jacksonville, Fla., who was not a member of the research group.

The new system, described on Wednesday in the journal Nature,deciphers the brain’s motor commands guiding vocal movement during speech — the tap of the tongue, the narrowing of the lips — and generates intelligible sentences that approximate a speaker’s natural cadence. Experts said the new work represented a “proof of principle,” a preview of what may be possible after further experimentation and refinement. The system was tested on people who speak normally; it has not been tested in people whose neurological conditions or injuries, such as common strokes, could make the decoding difficult or impossible. For the new trial, scientists at the University of California, San Francisco, and U.C. Berkeley recruited five people who were in the hospital being evaluated for epilepsy surgery.

Many people with epilepsy do poorly on medication and opt to undergo brain surgery. Before operating, doctors must first locate the “hot spot” in each person’s brain where the seizures originate; this is done with electrodes that are placed in the brain, or on its surface, and listen for telltale electrical stormsPinpointing this location can take weeks. In the interim, patients go through their days with electrodes implanted in or near brain regions that are involved in movement and auditory signaling. These patients often consent to additional experiments that piggyback on those implants.

Five such patients at U.C.S.F. agreed to test the virtual voice generator. Each had been implanted with one or two electrode arrays: stamp-size pads, containing hundreds of tiny electrodes, that were placed on the surface of the brain. As each participant recited hundreds of sentences, the electrodes recorded the firing patterns of neurons in the motor cortex. The researchers associated those patterns with the subtle movements of the patient’s lips, tongue, larynx and jaw that occur during natural speech. The team then translated those movements into spoken sentences.

Source: https://www.nytimes.com/

Molecular Nanocomputers

Computer scientists at Caltech have designed DNA molecules that can carry out reprogrammable computations, for the first time creating so-called algorithmic self-assembly in which the same “hardware” can be configured to run differentsoftware.”

A team headed by Caltech‘s Erik Winfree (PhD ’98), professor of computer science, computation and neural systems, and bioengineering, showed how the DNA computations could execute six-bit algorithms that perform simple tasks. The system is analogous to a computer, but instead of using transistors and diodes, it uses molecules to represent a six-bit binary number (for example, 011001) as input, during computation, and as output. One such algorithm determines whether the number of 1-bits in the input is odd or even, (the example above would be odd, since it has three 1-bits); while another determines whether the input is a palindrome; and yet another generates random numbers.

Think of them as nano apps,” says Damien Woods, professor of computer science at Maynooth University near Dublin, Ireland, and one of two lead authors of the study. “The ability to run any type of software program without having to change the hardware is what allowed computers to become so useful. We are implementing that idea in molecules, essentially embedding an algorithm within chemistry to control chemical processes.”

The system works by self-assembly: small, specially designed DNA strands stick together to build a logic circuit while simultaneously executing the circuit algorithm. Starting with the original six bits that represent the input, the system adds row after row of molecules—progressively running the algorithm. Modern digital electronic computers use electricity flowing through circuits to manipulate information; here, the rows of DNA strands sticking together perform the computation. The end result is a test tube filled with billions of completed algorithms, each one resembling a knitted scarf of DNA, representing a readout of the computation. The pattern on each “scarf” gives you the solution to the algorithm that you were running. The system can be reprogrammed to run a different algorithm by simply selecting a different subset of strands from the roughly 700 that constitute the system.

We were surprised by the versatility of programs we were able to design, despite being limited to six-bit inputs,” says David Doty, fellow lead author and assistant professor of computer science at the University of California, Davis. “When we began experiments, we had only designed three programs. But once we started using the system, we realized just how much potential it has. It was the same excitement we felt the first time we programmed a computer, and we became intensely curious about what else these strands could do. By the end, we had designed and run a total of 21 circuits.”

The findings have been reported in the journal Nature.

Source: https://www.caltech.edu/

Have China’s CRISPR Twins Enhanced Brains?

New research suggests that a controversial gene-editing experiment to make children resistant to HIV may also have enhanced their ability to learn and form memories. The twins, called Lulu and Nana, reportedly had their genes modified before birth by a Chinese scientific team using the new editing tool CRISPR. The goal was to make the girls immune to infection by HIV, the virus that causes AIDS. Now, new research shows that the same alteration introduced into the girls’ DNA, deletion of a gene called CCR5, not only makes mice smarter but also improves human brain recovery after stroke, and could be linked to greater success in school.

The answer is likely yes, it did affect their brains,” says Alcino J. Silva, a neurobiologist at the University of California, Los Angeles, whose lab uncovered a major new role for the CCR5 gene in memory and the brain’s ability to form new connections.

“The simplest interpretation is that those mutations will probably have an impact on cognitive function in the twins,” says Silva. He says the exact effect on the girls’ cognition is impossible to predict, and “that is why it should not be done.”

The Chinese team, led by He Jiankui of the Southern University of Science and Technology in Shenzhen, claimed it used CRISPR to delete CCR5 from human embryos, some of which were later used to create pregnanciesHIV requires the CCR5 gene to enter human blood cells.

The experiment has been widely condemned as irresponsible, and He is under investigation in China. News of the first gene-edited babies also inflamed speculation about whether CRISPR technology could one day be used to create super-intelligent humans, perhaps as part of a biotechnology race between the US and China.

There is no evidence that He actually set out to modify the twins’ intelligence. MIT Technology Review contacted scientists studying the effects of CCR5 on cognition, and they say the Chinese scientist never reached out to them, as he did to others from whom he hoped to get scientific advice or support.
As far as I know, we never heard from him,” says Miou Zhou, a professor at the Western University of Health Sciences in California.

Although He never consulted the brain researchers, the Chinese scientist was certainly aware of the link between CCR5 and cognition.  It was first shown in 2016 by Zhou and Silva, who found that removing the gene from mice significantly improved their memory. The team had looked at more than 140 different genetic alterations to find which made mice smarter.

Source: https://www.technologyreview.com/

The Ionocraft, Insect-sized Drone That Flies Without Any Moving Parts

Developed by researchers from the University of California, Berkeley, it’s not only described as the smallest flying robot ever made, but one which flies with zero moving parts: meaning no rotors, wings, or similar appendages. Instead, the insect-scale robot relies on atmospheric ion thrusters which allow it to move completely silently.

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To understand how it works, imagine two asymmetric — [such as] a wire and a plate — electrodes,” said Daniel Drew, currently a Postdoctoral Fellow in the Mechanical Engineering department at Stanford University. “When a voltage is applied between the two, the electric field will be stronger in the vicinity of the wire as a function of its geometry. If this field is strong enough, an ambient electron can be pulled in with enough kinetic energy to initiate avalanche breakdown through impact ionization. There’s now a stable plasma, glowing purple in the dark, around the top wire. Generated ions will be ejected from this plasma, drifting in the electric field towards the bottom electrode. Along the way, they collide with neutral air molecules and impart momentum, producing a net thrust.”

Source: https://people.eecs.berkeley.edu/
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Jell-O To Make Powerful New Hydrogen Fuel Catalyst

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 expensivewater-splitting catalyst out there.

The catalyst, which is composed of nanometer-thin sheets of metal carbide, is manufactured using a self-assembly process that relies on a surprising ingredient: gelatin, the material that gives Jell-O its jiggle.

Two-dimensional metal carbides spark a reaction that splits water into oxygen and valuable hydrogen gas. Berkeley researchers have discovered an easy new recipe for cooking up these nanometer-thin sheets that is nearly as simple as making Jell-O from a box

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 print edition of the journal Advanced Materials.

Source: https://news.berkeley.edu/

Immunotherapy Technique Specifically Targets Tumor Cells

A new immunotherapy screening prototype developed by University of California, Irvine (UCI) researchers can quickly create individualized cancer treatments that will allow physicians to effectively target tumors without the side effects of standard cancer drugsUCI’s Weian Zhao and Nobel laureate David Baltimore with Caltech led the research team that developed a tracking and screening system that identifies T cell receptors with 100-percent specificity for individual tumors within just a few days.

In the human immune system, T cells have molecules on their surfaces that bind to antigens on the surface of foreign or cancer cells. To treat a tumor with T cell therapy, researchers must identify exactly which receptor molecules work against a specific tumor’s antigens. UCI researchers have sped up that identification process.

This technology is particularly exciting because it dismantles major challenges in cancer treatments,” said Zhao, an associate professor of pharmaceutical sciences. “This use of droplet microfluidics screening significantly reduces the cost of making new cancer immunotherapies that are associated with less systemic side effects than standard chemotherapy drugs, and vastly speeds up the timeframe for treatment.

Zhao added that traditional cancer treatments have offered a one-size-fits-all disease response, such as chemotherapy drugs which can involve systemic and serious side effects.

Research findings appear in Lab on a Chip.

Source: https://news.uci.edu/

Mapping Genes Of All Complex Life On Earth

In an effort to protect and preserve the Earth’s biodiversity and kick-start an inclusive bio-economy, the World Economic Forum have announced a landmark partnership between the Earth BioGenome Project, chaired by Harris Lewin, distinguished professor at the University of California, Davis, and the Earth Bank of Codes to map the DNA of all life on Earth. The announcement was made at the 48th World Economic Forum Annual Meeting in Davos-Klosters, Switzerland.

The Earth Biogenome Project aims to sequence the DNA of all the planet’s eukaryotessome 1.5 million known species including all known plants, animals and single-celled organisms. The ambitious project will take 10 years to complete and cost an estimated $4.7 billion. Of the estimated 15 million eukaryotic species, only 10 percent have been taxonomically classified. Of that percentage, scientists have sequenced the genomes of around 15,000 species, less than 0.1 percent of all life on Earth.

The partnership will construct a global biology infrastructure project to sequence life on the planet to enable solutions for preserving the Earth’s biodiversity, managing ecosystems, spawning bio-based industries and sustaining human societies,” said Lewin, who chairs the Earth BioGenome Project working group. Lewin holds appointments in the Department of Evolution and Ecology and the UC Davis Genome Center.

Source: https://www.universityofcalifornia.edu/

Genes Behind Humankind’s Big Brain

Scientists have pinpointed three genes that may have played a pivotal role in an important milestone in human evolution: the striking increase in brain size that facilitated cognitive advances that helped define what it means to be human. These genes, found only in people, appeared between 3 and 4 million years ago, just prior to a period when the fossil record demonstrates a dramatic brain enlargement in ancestral species in the human lineage, researchers said. The three nearly identical genes, as well as a fourth nonfunctional one, are called NOTCH2NL genes, arising from a gene family dating back hundreds of millions of years and heavily involved in embryonic development. 

The NOTCH2NL genes are particularly active in the reservoir of neural stem cells of the cerebral cortex, the brain’s outer layer responsible for the highest mental functions such as cognition, language, memory, reasoning and consciousness. The genes were found to delay development of cortical stem cells into neurons in the embryo, leading to the production of a higher number of mature nerve cells in this brain region.

The cerebral cortex defines to a large extent what we are as a species and who we are as individuals. Understanding how it emerged in evolution is a fascinating question, touching at the basic origins of mankind,” said developmental neurobiologist Pierre Vanderhaeghen of Université Libre de Bruxelles and VIB/KULeuven in Belgium.

It is the ultimate evolutionary question and it is thrilling to work in this area of research,” added biomolecular engineer David Haussler, scientific director of the University of California, Santa Cruz Genomics Institute and a Howard Hughes Medical Institute investigator.

Source: https://www.reuters.com/