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HIV-1 replication and integration in vitro

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To infect a host cell, HIV-1 must reverse transcribe its single-stranded RNA genome into a double-stranded DNA copy and integrate that copy into a host chromosome. Reverse transcription and integration have been characterized separately but have not been reconstituted together outside of the cell. Christensen et al. now report that viral core particles can complete full reverse transcription and integration in a cell-free system. The external capsid shell of the core is required for efficient reverse transcription, and the replicating DNA can loop out of capsid openings. Integration requires cell extract, and this cell-free system should be useful for analyzing how host factors contribute to the first half of the HIV life cycle.

Science, this issue p. eabc8420

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How to ‘watch’ NASA’s OSIRIS-REx snatch a sample from near-Earth asteroid Bennu

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NASA’s OSIRIS-REx probe is about to touch down on an asteroid for a smash-and-grab mission, and you can follow its progress live — kind of. The craft is scheduled to perform its collection operation this afternoon, and we’ll know within minutes if all went according to plan.

OSIRIS-REx, which stands for Origins Spectral Interpretation Resource Identification Security – Regolith Explorer, was launched in September of 2016 and since arriving at its destination, the asteroid Bennu, has performed a delicate dance with it, entering an orbit so close it set records.

Today is the culmination of the team’s efforts, the actual “touch and go” or TAG maneuver that will see the probe briefly land on the asteroid’s surface and suck up some of its precious space dust. Just a few seconds later, once sampling is confirmed, the craft will jet upwards again to escape Bennu and begin its journey home.

Image Credits: NASA

Image Credits: NASA

While there won’t be live HD video of the whole attempt, NASA will be providing both a live animation of the process informed by OSIRIS-REx’s telemetry, and presumably any good images that are captured as it descends.

We know for certain this is both possible and very cool because Japan’s Hayabusa-2 asteroid mission did something very similar last year, but with the added complexity (and coolness) of firing a projectile into the surface to stir things up and get a more diverse sample.

NASA’s coverage starts at 2 PM Pacific, and the touchdown event is planned to take place an hour or so later, at 3:12 if all goes according to plan. You can watch the whole thing take place in simulation at this Twitch feed, which will be updated live, but NASA TV will also have live coverage and commentary on its YouTube channel. Images may come back from the descent and collection, but they’ll be delayed (it’s hard sending lots of data over a million-mile gap) so if you want the latest, listen closely to the NASA feeds.

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Intel is providing the smarts for the first satellite with local AI processing on board

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Intel detailed today its contribution to PhiSat-1, a new tiny small satellite that was launched into sun-synchronous orbit on September 2. PhiSat-1 has a new kind of hyperspectral-thermal camera on board, and also includes a Movidius Myriad 2 Vision Processing Unit. That VPU is found in a number of consumer devices on Earth, but this is its first trip to space – and the first time it’ll be handling large amounts of local data, saving researchers back on Earth precious time and satellite downlink bandwidth.

Specifically, the AI on board the PhiSat-1 will be handling automatic identification of cloud cover – images where the Earth is obscured in terms of what the scientists studying the data actually want to see. Getting rid of these images before they’re even transmitted means that the satellite can actually realize a bandwidth savings of up to 30%, which means more useful data is transmitted to Earth when it is in range of ground stations for transmission.

The AI software that runs on the Intel Myriad 2 on PhiSat-1 was created by startup Ubotica, which worked with the hardware maker behind the hyperspectral camera. It also had to be tuned to compensate for the excess exposure to radiation, though a bit surprisingly testing at CERN found that the hardware itself didn’t have to be modified in order to perform within the standards required for its mission.

Computing at the edge takes on a whole new meaning when applied to satellites on orbit, but it’s definitely a place where local AI makes a ton of sense. All the same reasons that companies seek to handle data processing and analytics at the site of sensors hear on Earth also apply in space – but magnified exponentially in terms of things like network inaccessibility and quality of connections, so expect to see a lot more of this.

PhiSat-1 was launched in September as part of Arianspace’s first rideshare demonstration mission, which it aims to use to show off its ability to offer launch services to smaller startups for smaller payloads at lower costs.

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This 14-Year-Old’s Discovery Could Lead to a Cure for COVID-19

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With no clear end in sight to the pandemic, there is an urgent need for a cure to COVID-19. As scientists around the world work to develop possible vaccines, one 14-year-old girl from Texas has made a new discovery that could lead to a potential treatment.

On Wednesday, Anika Chebrolu from Frisco, Texas was named the winner of the 3M Young Scientist Challenge after discovering a molecule that can selectively bind to the spike protein of the SARS-COV-2 virus, which causes COVID-19.

The competition opened in December 2019 and invited students in grades five to eight to find a unique solution to an everyday problem. Anika won $25,000, a special destination trip, and the title of “America’s Top Young Scientist” for her achievement.

Her discovery could lead to important developments in COVID-19 research. By binding to the spike protein in the coronavirus, the molecule she found can potentially prevent virus entry into the host cell, and can be used in creating a potential drug to cure COVID-19.

Anika used in-silico methodology — methods and experiments that make use of computers — to screen millions of small molecules. She originally planned for her project to focus on the influenza virus, but pivoted once COVID-19 hit and she realized the severity of the pandemic. Anika was in eighth grade when she submitted the project.

She told CNN that she hopes to work with other scientists and researchers to develop her discovery into an actual cure for the virus.

At the moment, the World Health Organization (WHO) is tracking over 170 candidate vaccines around the world. However, since many of them are still in early development, the effectiveness of these vaccines are still unknown. Vaccines go through multiple stages of testing and experts predict that a vaccine will only be available to the public in 2021, at the earliest.

In August, Russia was the first country to claim to have developed a vaccine for COVID-19. However, many were skeptical as President Vladimir Putin had ordered to speed up clinical trials. The vaccine, which was not subject to the extensive Phase III testing, was registered after less than two months of human testing. Experts have said that the vaccine is based on a common cold virus, which many people have been exposed to, potentially limiting its effectiveness. Other countries working on vaccines include the United Kingdom, Germany, and China.

At the moment, there are no specific vaccines or drugs for COVID-19. Developing one to prevent or cure infection from the novel coronavirus could help decrease the number of fatalities and help hospitals manage patients better.

As of posting, there have been a total of over 40 million cases of COVID-19 and 1.1 million deaths around the world. The United States and India have the most number of cases, with 8.1 million and 7.5 million total COVID-19 cases respectively. Few places across the globe have successfully managed  the virus, including New Zealand, Taiwan, and Singapore.

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