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Lenovo introduces new Windows, Chromebook education laptops to classrooms

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Lenovo 500e Chromebook

As part of its educational announcement yesterday, Microsoft unveiled a new low-cost Lenovo laptop running Windows 10 and priced to compete with Chromebooks in the classroom market. But, ironically, Lenovo itself was busy announcing additional new education notebooks, some of which include Chromebooks.

The device that Microsoft introduced is the 300e, a 2-in-1 system that includes pen support for the Windows version. However, Lenovo is also offering the 300e in a Chromebook edition for the same $279 starting price. The Chrome-running version lacks pen support and relies on a MediaTek MTK 8173C processor instead of the Intel Apollo Lake CPUs that the Windows 300e will ship with.

Lenovo has an even cheaper option in the 100e, which has a traditional clam-shell design, an Intel Celeron N3350 processor, and a $219 price point whether you choose the Windows or Chromebook flavor. The 500e is a Chromebook-only 2-in-1 that features a Gorilla Glass screen, pen support with an integrated compartment to store the stylus, and up to 8GB of RAM and 64GB of storage, albeit with a higher starting price of $349.

Rounding out Lenovo’s new offerings are pricier Windows laptops with more familiar names. The latest versions of the ThinkPad 11e and 11e Yoga are thinner and lighter and pack greater battery life than their predecessors. They also include Intel’s latest N processors, and the Yoga convertible comes with a pen and integrated compartment like the 500e. To handle the drops and spills children may expose the systems to, both have been built to MIL-SPEC standards for rugged construction.

The ThinkPad 11e and 11e Yoga will be available next month starting at $429 and $499, respectively. The Windows editions of the 100e and 300e ship this month, while the Chrome 100e will ship in March and the 300e Chromebook in February. The Chromebook 500e is available this month as well.

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How many turkey feathers does it take to make an ancient blanket? 11,500

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Enlarge / A segment of fiber cord that has been wrapped with turkey feathers, along with a single downy feather.

Indigenous Pueblo populations in the American Southwest—ancestors of today’s Hopi, Zuni, and Rio Grande Pueblo tribes—typically wove blankets, cloaks, and funeral wrappings out of animal hides, furs, and turkey feathers. Anthropologists at Washington State University (WSU) have examined one such ancient turkey-feather blanket and determined it took thousands of those feathers, wrapped around nearly 200 yards to yucca fiber, to make, according to a new paper published in the Journal of Archaeological Science: Reports.

“Blankets or robes made with turkey feathers as the insulating medium were widely used by Ancestral Pueblo people in what is now the Upland Southwest, but little is known about how they were made because so few such textiles have survived due to their perishable nature,” said co-author Bill Lipe, emeritus professor of anthropology at WSU. “The goal of this study was to shed new light on the production of turkey feather blankets and explore the economic and cultural aspects of raising turkeys to supply the feathers.”

For their study, Lipe and his WSU colleague and co-author, Shannon Tushingham, studied a blanket framework on display at the Edge of the Cedars State Park Museum in Blanding, Utah. Although insects had devoured the original feather vanes and barbs, the shafts were still visible, wrapped around yucca fiber cords. They were also able to look at a second, smaller blanket which still had most of its feathers intact. Both blankets roughly date to the early 1200s CE.

According to the authors, such blankets were likely made from the body feathers that cover the breast and back of turkeys. Such feathers have a visible “after feather,” as well as a downy portion—a key factor in how feathers keep turkeys and people warm. Both the distal tips and the quills at the base are typically overwrapped during the weaving process, with the downy portions exposed. They are held together by rows of nonwrapped yucca fiber cords, which comprise the weave of the blanket. They measured the length of the cordage used to make the warps and wefts, the two components in weaving used to turn thread or yarn into fabric (lengthwise yarns are called warp; crosswise yarns are called weft).

No rush

The blanket might have been created all at once, but the authors surmise that additional lengths of cordage and feather batches were probably added over time. However, they do think the feathers were added to the full warp cord before the final blanket took shape, “before the cord was repeatedly doubled back on itself to form the individual warp segments,” they wrote.

They also counted the number of individual feather shafts on several segments of the warp cords. However, it wasn’t possible to examine the quills or ends of the feathers, or the distal tips, since they had been overwrapped by adjacent feathers. Ultimately, the researchers estimated that approximately 11,500 turkey feathers would have been needed to make the blanket. “This estimate would of course change if different lengths of feather were used,” they wrote, depending on the feathers that were available and on the personal preferences of whoever wove the blanket.

Bill Lipe and Shannon Tushingham collect feathers from a wild-turkey pelt in Tushingham's lab at Washington State University in Pullman, Washington.
Enlarge / Bill Lipe and Shannon Tushingham collect feathers from a wild-turkey pelt in Tushingham’s lab at Washington State University in Pullman, Washington.

Washington State University

Next, the researchers obtained the pelts of two adult male wild turkeys from Idaho hide and fur dealers, the better to estimate how many adult turkeys would be needed to provide 11,500 or so feathers. They concluded such pelts would yield a little over 2,700 feathers from an adult male turkey. From that, they extrapolated that a blanket-maker would need to collect feathers from 4.26 adult males. But since only 1,200 feathers per bird were in the preferred size range, it may have taken as many as 9.6 adult birds to collect enough feathers for the blanket. The good news: “Once a blanket was made, it likely would have lasted for a number of years,” the authors wrote.

Turkey feathers likely began to replace strips of rabbit skin for blankets sometime during the first two centuries CE. “As ancestral Pueblo farming populations flourished, many thousands of feather blankets would likely have been in circulation at any one time,” said Tushingham. “It is likely that every member of an ancestral Pueblo community, from infants to adults, possessed one.”

As for how the feathers were collected, Lipe and Tushingham cited three possibilities: the birds were killed and their feathers harvested; feathers were collected during the birds’ natural molting season; or people selectively plucked mature feathers from living turkeys. Turkeys didn’t become a major food source in this region until between 1100 and 1200 CE, and even then, they were typically killed before they were a year old—too soon to harvest mature feathers. Furthermore, “Killing turkeys for their feathers is a wasteful strategy, because it removes the possibility of harvesting feathers as a sustainable food source,” the authors wrote.

“Reverence for turkeys”

As for collecting feathers during the natural molting season, this typically occurs gradually over weeks or months. If the turkeys were roaming freely, it would be difficult to collect the best feathers, and if they were penned, the feathers would be trampled in the ground—no doubt also littered with turkey droppings. (The authors note that modern wild turkeys produce 2.5 pounds of “fresh manure” per bird each week.) Thus, the authors conclude that the most likely practice was to selectively pluck feathers from live birds, which can be done quite easily once feathers have matured.

“When the blanket we analyzed for our study was made, we think in the early 1200s CE, the birds that supplied the feathers were likely being treated as individuals important to the household and would have been buried complete,” Lipe said. “This reverence for turkeys and their feathers is still evident today in Pueblo dances and rituals. They are right up there with eagle feathers as being symbolically and culturally important.”

“Turkeys were one of the very few domesticated animals in North America until Europeans arrived in the 1500s and 1600s,” Tushingham added. “They had and continue to have a very culturally significant role in the lives of Pueblo people, and our hope is this research helps shed light on this important relationship.”

DOI: Journal of Archaeological Science: Reports, 2020. 10.1016/j.jasrep.2020.102604 (About DOIs).

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A mildly insane idea for disabling the coronavirus

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Enlarge / Diagram of the structure of the virus’ spike protein.

When the COVID-19 pandemic was first recognized for the threat that it is, researchers scrambled to find anything that might block the virus’ spread. While vaccines have grabbed much of the attention lately, there was also the hope that we could develop a therapy that would block the worst effects of the virus. Most of these have been extremely practical: identify enzymes that are essential for the virus to replicate, and test drugs that block similar enzymes from other viruses. These drugs are designed to be relatively easy to store and administer and, in some cases, have already been tested for safety in humans, making them reasonable choices for getting something ready for use quickly.

But the tools we’ve developed in biotechnology allow us to do some far less practical things, and a paper released today describes how they can be put to use to inactivate SARS-CoV-2. This is in no way a route to a practical therapy, but it does provide a fantastic window into what we can accomplish by manipulating biology.

Throw it in the trash

The whole effort described in the new paper is focused on a simple idea: if you figure out how to wreck one of the virus’ key proteins, it won’t be able to infect anything. And, conveniently, our cells have a system for destroying proteins, since that’s often a useful thing to do. In some cases, the proteins that are destroyed are damaged; in others, the proteins are made and destroyed at elevated paces to allow the cell to respond to changing conditions rapidly. In a few cases, changes in the environment or the activation of signaling pathways can trigger widespread protein destruction, allowing the cell to quickly alter its behavior.

This system relies on a small protein called “ubiquitin.” When a protein is to be targeted for destruction, enzymes called ubiquitin ligases chemically link a chain of ubiquitins to it. These serve as a tag that is recognized by enzymes that digest any proteins with ubiquitin attached to them.

So, the idea behind the new work is to identify a key viral protein, and figure out how to attach ubiquitin to it. The cell would then take care of the rest, digesting the viral protein and thus blocking the production of any useful viruses in that cell. In this case, the researchers decided to target the spike protein that sits on the surface of coronaviruses and allows them to attach to and infect new cells.

Unfortunately, there are no proteins that attach ubiquitin to the viral spike protein. Or, rather, there were no proteins that fit that description.

But a team at Harvard has now produced one.

Bioengineering

The team’s method of doing so started with the fact that we do know something that sticks to the viral spike protein: the cellular protein it latches on to in order to enter the cell. This is called the angiotensin-converting enzyme 2, or ACE2, but we’ll call it the green protein because that’s the color we use in this diagram. The idea was to find a part of this protein that stuck to spike (aka the red protein) and link that to a ubiquitin-adding protein (blue). Seems simple enough.

At left, the normal interactions between viral spike (red) and ACE2 (green) during infection. At right, using those interactions to target the spike protein for destruction.
Enlarge / At left, the normal interactions between viral spike (red) and ACE2 (green) during infection. At right, using those interactions to target the spike protein for destruction.

John Timmer

But there’s a complication: the green protein also sticks to other proteins found on healthy, uninfected cells. So, if you’re not careful, your virus-destroying enzyme will also end up destroying proteins that are essential to the health of uninfected cells. Which would be a rather large “oopsie.”

To solve this problem, the researchers downloaded the data that showed the atomic-level details of the structure of the red and green proteins, as well as how those proteins interact. (Yes, it’s available.) Then they transferred this data into a software package that finds the most energetically favored interactions between proteins. (Yes, those exist.) They they asked the program to virtually slice the green protein up and find smaller pieces that satisfied two conditions: the pieces stuck to the virus’ red protein but not to the one found on the surface of healthy human cells.

With a red-specific bit of the green protein identified, the researchers fused it to something that stuck to the blue protein, which would link ubiquitin to the red one. This hybrid would act as a bridge, linking the viral red protein to a blue one that would attach ubiquitin to it.

The plan: bring in the blue enzyme to attach ubiquitin to the spike protein, leading to its destruction and thus blocking the production of viruses.
Enlarge / The plan: bring in the blue enzyme to attach ubiquitin to the spike protein, leading to its destruction and thus blocking the production of viruses.

John Timmer

This worked, but not especially well. The authors linked spike (the red one) to a fluorescent protein and found out that producing their hybrid protein dropped the fluorescence by about 30 percent. Better than nothing—but not great.

Optimization

So, how to make it better? The researchers used the software package to make mutations at every single location in their green protein fragment, and they checked what each one did for its affinity for the viral spike protein. Anything that looked promising, they engineered into the actual protein. One of these boosted the performance considerably; now, instead of lowering the fluorescence by 30 percent, it dropped by 50 percent.

But that wasn’t the end of their efforts. They green fragment/linker hybrid they built served as a bridge by sticking to both the red protein and the ubiquitin-attaching blue one. To boost the efficiency further, the researchers simplified things a bit by directly connecting the blue enzyme to the green fragment. With that in place, there’s a direct link between the protein the red one sticks to and the blue one that ensures its destruction. This cut the amount of fluorescent spike protein present in cells by 60 percent.

So, an amazing application of biotechnology, right? Unfortunately, it’s also likely to be absolutely useless, and not just because we don’t know whether a 60 percent reduction is meaningful. For this to be effective, it would have to be made by cells as they have active infections. Which means we have to insert the gene that encodes the protein they built into cells, at least temporarily. We can definitely do that—it’s technology some of the leading vaccine candidates rely on. But to get a vaccine to work, we don’t need to get a gene active in that many cells. To protect an entire organ, we might.

The conclusion: this is likely to be a non-starter, especially given that there are promising vaccines and many other potential therapies ahead of it in the pipeline for safety testing. Still, the things that make this sort of technology wildly impractical for use to treat humans for a virus may not apply to other use cases like bacteria, crops, animals, or even less urgent medical needs. So, while the details of this work aren’t really significant, the fact that we’ve developed all the underlying technology needed for it is worth keeping in mind.

Communications Biology, 2020. DOI: 10.1038/s42003-020-01470-7 (About DOIs).

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AstraZeneca’s best COVID vaccine result was a fluke. Experts have questions

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Enlarge / Vials in front of the AstraZeneca British biopharmaceutical company logo are seen in this creative photo taken on 18 November 2020.

Pharmaceutical giant AstraZeneca and the University of Oxford made an exciting announcement Monday: the COVID-19 vaccine they developed together appeared up to 90 percent effective at preventing disease. But in the days since, that exciting news melted into a pool of confusion after it became clear that the 90 percent figure came about from a complete accident. Now, experts are scratching their heads over what actually happened in the trial and what it means for the vaccine’s future.

The questions all swirl around the vaccine’s dosage regimen. In initial press releases, AstraZeneca and Oxford explained that researchers had used two different dosage regimens to test their experimental vaccine, AZD1222. In one regimen, trial participants received two “full” vaccine doses, 28 days apart. In the other, participants received a half dose of vaccine followed by a full dose 28 days later.

Pooling results from trials in the United Kingdom and another in Brazil, the researchers found the two-full-dose regimen was 62 percent effective at preventing COVID-19—a good, but not great result. The half-dose/full-dose regimen, on the other hand, appeared 90 percent effective—a rather impressive result.

The trouble is, there was never supposed to be a half-dose-full-dose regimen in any of the trials.

Serendipity?

“The reason we had the half-dose is serendipity,” Mene Pangalos, AstraZeneca’s head of non-oncology research and development, told Reuters in an interview Monday.

Pangalos explained that when the UK trial first began, Oxford researchers were giving patients their first round of shots and noticed that the vaccine’s side-effects—fatigue, headache, arm aches—were milder than expected.

“So, we went back and checked … and we found out that they had underpredicted the dose of the vaccine by half,” Pangalos said. The researchers then decided to continue on with the trial and give the relatively small number of incorrectly dosed patients the proper dose for their second shot.

In the pooled trial analysis, 2,741 participants were recruited while the incorrect half-dose/full-dose regimen was used and 8,895 participants were involved in the analysis of the two-full-dose regimen.

AstraZeneca and Oxford have been mum about how that error occurred exactly. Meanwhile, outside experts have raised doubt about whether the 90 percent efficacy with the half-dose/full-dose is even real, given the smaller number of participants.

Another wrinkle is that the dosing error occurred early in the trial when researchers were only recruiting people between the ages of 18 and 55—excluding older people more vulnerable to disease. The analysis with the two-full doses, on the other hand, did include older age groups.

Lingering questions

“There are a number of variables that we need to understand and what has been the role of each one of them in achieving the difference in efficacy,” Moncef Slaoui, chief scientist of the US government’s Operation Warp Speed, said in a press briefing Tuesday.

Operation Warp Speed has invested in AZD1222 and is supporting an ongoing trial of the vaccine in the US. Slaoui noted in the press conference that they knew about the dosing error at the time it happened. “When they realized that there was an error—or a change in the approach, the technique used—they corrected it,” he said.

Now that the results have come out, Slaoui says it’s important to dig into what was going on between the two regimens. For one thing, researchers should look to see if there are  different immune responses induced by the different dosages schemes. Some researchers have speculated that ramping up the vaccine dosage between the first and second shot could have helped build up better immune responses against the pandemic coronavirus, SARS-CoV-2.

Others have speculated that starting with a strong dose—as in the two-full-dose regimen— may have foiled efficacy because of the way AZD1222 is designed. The vaccine uses a weakened adenovirus as packaging to deliver to the immune system the genetic code for the SARS-CoV-2 spike protein. But starting out with a strong first dose may prime the immune system to focus on attacking the adenovirus, rather than the packaged coronavirus component, some think.

Once researchers have a better understanding of what was going on, then they can make decisions about altering the ongoing trials, Slaoui said. In the US, about 11,000 of a planned 40,000 participants have been recruited for a Phase III trial of AZD1222. So, it could still be altered to include the half-dose regimen if new information comes in. However, Salaoui noted that such information would have to come quickly, given the rate the pandemic is progressing in the US.

On a final note, Slaoui reemphasized that the difference in efficacy and the dosage error as whole could be meaningless in the end: “The 90 percent efficacy group and the 62 percent efficacy group are overlapping statistically, so it is still possible that that difference is a random difference,” he said. “It’s unlikely but it’s still possible it’s a random difference.”

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