sciencehabit shares a report from Science Magazine: Physicists at Google have taken an important step toward protecting delicate information in their nascent quantum computer from errors that can obliterate it. The researchers can't yet compensate for all types of errors -- a necessary step toward building a full-fledged quantum computer -- but others say they're poised to achieve that goal. Working with chains of up to 11 data qubits, Google researchers have now been able to preserve a logical qubit for a time that increases exponentially with the number of physical qubits, they report today in Nature. By spreading a single qubit's state over up to 11 data qubits, they reduced the chances of an error after 50 microseconds from 40% to 0.2%. Other groups have demonstrated similar error corrections schemes, but the new work is the first to demonstrate the exponential suppression of errors, says Julian Kelly, a physicist at Google and senior author on the paper. Such exponential suppression suggests developers may eventually be able to maintain a logical qubit indefinitely by spreading it over about 1000 physical qubits.

Covid cases are rising in all 50 US states as the Delta variant spreads coast to coast, news outlets reported on Friday , and with less than half the US population fully vaccinated, public health chiefs warned of an "extraordinary surge." Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), said at a White House briefing: "This is becoming a pandemic of the unvaccinated." The Guardian reports: Walensky said the US was seeing an average of 26,000 new coronavirus cases a day -- a seven-day average that is 70% higher than last week. Hospitalizations and deaths are also seeing increases -- about 36% and 26%, respectively, with Walensky noting this was another "critical moment" in the outbreak. "We are seeing outbreaks of cases in parts of the country that have low vaccination coverage because unvaccinated people are at risk. Communities that are fully vaccinated are generally faring well," she said.

Anthony Fauci, the nation's top infectious diseases official, said there had been an "extraordinary surge" in the Delta variant of Covid-19 -- which is more transmissible -- around the world, including in the US. Jeff Zients, the coordinator of the White House coronavirus team, confirmed that unvaccinated Americans "account for virtually all recent Covid-19 hospitalizations and deaths." Four states that are currently seeing high increases in Covid-19 cases have accounted for over 40% of the total Covid cases seen in the country this past week, Zients said. One in five cases occurred in Florida, in which about 50% of the state is fully vaccinated.

The Hubble Space Telescope has powered on once again. NASA was able to successfully switch to a backup computer on the observatory on Friday following weeks of computer problems. From a report: On June 13, Hubble shut down after a payload computer from the 1980s that handles the telescope's science instruments suffered a glitch. Now, over a month since Hubble ran into issues, which the Hubble team thinks were caused by the spacecraft's Power Control Unit (PCU), NASA switched to backup hardware and was able to switch the scope back on. With Hubble back online with this backup hardware, the Hubble team is keeping a close watch to make sure that everything works correctly, according to a statement from NASA.

The World Health Organization's chief scientist has advised individuals against mixing and matching Covid-19 vaccines from different manufacturers, saying such decisions should be left to public health authorities. From a report: "It's a little bit of a dangerous trend here," Soumya Swaminathan told an online briefing on Monday after a question about booster shots. "It will be a chaotic situation in countries if citizens start deciding when and who will be taking a second, a third and a fourth dose." Swaminathan had called mixing a âoedata-free zoneâ but later clarified her remarks in an overnight tweet. "Individuals should not decide for themselves, public health agencies can, based on available data," she said in the tweet. "Data from mix and match studies of different vaccines are awaited -- immunogenicity and safety both need to be evaluated."

sciencehabit shares a report from Science Magazine: A man unable to speak after a stroke has produced sentences through a system that reads electrical signals from speech production areas of his brain, researchers report this week. The approach has previously been used in non-disabled volunteers to reconstruct spoken or imagined sentences, but this is the first demonstration of its potential in the type of patient it's intended to help. The participant had a stroke more than 10 years ago that left him with anarthria -- an inability to control the muscles involved in speech. Researchers used a computational model known as a deep-learning algorithm to interpret patterns of brain activity in the sensorimotor cortex, a brain region involved in producing speech, and 'decoded' sentences he attempted to read aloud.

In the new study, [the researchers] temporarily removed a portion of the participant's skull and laid a thin sheet of electrodes smaller than a credit card directly over his sensorimotor cortex. To "train" a computer algorithm to associate brain activity patterns with the onset of speech and with particular words, the team needed reliable information about what the man intended to say and when. So the researchers repeatedly presented one of 50 words on a screen and asked the man to attempt to say it on cue. Once the algorithm was trained with data from the individual word task, the man tried to read sentences built from the same set of 50 words, such as "Bring my glasses, please." To improve the algorithm's guesses, the researchers added a processing component called a natural language model, which uses common word sequences to predict the likely next word in a sentence. With that approach, the system only got about 25% of the words in a sentence wrong, they report today in The New England Journal of Medicine. With the new approach, the man could produce sentences at a rate of up to 18 words per minute.