After a year of speculation over a brewing mental health crisis among kids and adolescents, in June the Centers for Disease Control and Prevention finally released data showing that starting in February of 2021, the number of suspected suicide attempts had dramatically increased among girls ages 12-17 in the United States as compared to 2019. You could almost hear a collective, we told you so, from pundits who had spent the year decrying the closure of schools as Covid-19 tore through the country. To them, these statistics were proof positive that closing schools had brutalized kids.

Here’s the snag: the rate of suicide attempts appears to have been inversely related to school closures. That is, when schools closed, suspected suicide attempts actually decreased. When schools reopened, suspected suicide attempts skyrocketed in lockstep.

The rate of suicide attempts appears to have been inversely related to school closures.

Take a look at the animation that we created for Inside Medicine below using CDC data and detailed statistics on US school closures during the Covid-19 pandemic.‡ It illustrates the association dramatically. When Covid-19 erupted on American soil in March of 2020, schools closed en masse. Right when that happened, suicide attempts among teen girls dropped. Things get a little noisy, but the overall correlation is uncanny. Schools opened more in the fall, suicide attempts rose. Schools closed for winter vacation, suicide attempts plunged for a time. The 2021 portion of the graph is particularly startling. As the percent of open schools approached 75% of normal, the number of suicide attempts increased suddenly.

< View the graphical video at the source page. >

While an increase in suspected suicide attempts was not observed among adolescent boys during the same period as attempts rose among girls, the earlier association between school closures and a decrease in suicide attempts was observed in boys too, just as it had been in girls.

< View the graphical video at the source page. >

While these graphs tell us nothing about causation, we ran the numbers and found the degree of association to be “very strong,” which is the highest category statistically possible.

You may have noticed that the initial decline in suicide attempts at the outset of the pandemic in the United States in March of 2020 was not any kind of all-time low. In fact, suicide attempts in adolescent girls dropped to rates similar to those seen in the summer of 2019. That’s not unexpected. Suicide death rates (for which we have decades of reliable data) among teens and young adults predictably fall during summer months, and also in December—that is, times when schools are the least in session. So, what our graphs above show, an apparent inverse correlation between school closings and suicidal behavior, is not unique to the Covid-19 pandemic.

•••

Does any of this match the prevailing narrative around school closures during the Covid-19 pandemic? Not in my experience. In fact, the most common narrative I have seen, coming from concerned parents and academics alike, is that school closures fueled an increase in suicidal behavior among students. This had been an untested assertion. If anything, the data here imply the exact opposite.

But is that really the case? Did school closures decrease suicidal behavior? Did opening schools after a long break create or even contribute to a large surge in suicide attempts in adolescent girls?

The most likely scenario is that suicidality is simply too complex a phenomenon to neatly align with any one particular policy or explanation, especially during a once-in-a-century disruption to life as we knew it. While many people will see the graphs above as evidence that, in actuality, school closures reduced suicidality among teens and that opening schools after the deadliest winter in modern American history increased teen suicidality, the truth could be far more mundane than that: that pandemic-related school closures and suicidal behaviors among adolescents have no direct cause-and-effect relationship. To be clear, these graphs do not prove that opening schools made more adolescent girls more suicidal—though that would be an understandable interpretation, given the breathtaking trends they illustrate. But they certainly do show, and rather impressively, that closing schools did not by any means increase suicidal behavior one bit.

In writing this, I have found the surprising reverse correlation between suicidal behavior and time spent in school—both prior to the Covid-19 pandemic and during it—gnawing at me. Could it be that the pressures around school itself are among the most important stressors related to suicidality among teens? If that’s so, the underlying reasons could be related either to academic or social pressures. Regardless, no one would argue that we should do away with in-person learning just because more time spent in the classroom appears to be associated with increased rates of attempted or completed suicide. But it is an upsetting insight, nonetheless. The problem of adolescent suicide demands a comprehensive approach. Suicide deaths among adolescents rose around 50% over the last decade, from around 60 deaths per one million teens annually to around 90 suicide deaths per one million teens annually. The Covid-19 pandemic did not create this problem, but it might yet teach us something about it.

•••

The effect that Covid-19 school closures has had on children and adolescents is unknown. Some have argued that we have forfeited nearly a year of learning, especially among certain vulnerable populations. But it’s unclear what exactly those loses are, how to quantify them, and whether they are insurmountable. For example, children with cancer often miss many months or more of their normal schooling. But survivors don’t seem to have any long-term differences in scholastic achievement as compared to their healthy peers. Whatever setbacks pediatric cancer survivors face in their education are apparently not permanent in a majority of cases. However, these children often have the benefit of hospital and community-based support systems, designed to keep them from falling too far behind. This then quickly becomes a question of resources and priorities.

The United States has not handled Covid-19 mitigation correctly, especially with respect to children. Can you name a project more essential to the long-term success of our communities than education? And yet in far too many regions of the country, restaurants and bars opened while schools remained shuttered.

Failing to control Covid-19 should be considered a national stain. Even setting the school issue aside, I can think of almost nothing that has harmed children more than our ineptitude in controlling Covid-19 during 2020 and the winter of 2021. Hundreds of children in the United States died of Covid-19, thousands more suffered complications, and tens of thousands of parents of school-aged children died. This is an American tragedy; American in particular because we possess the financial resources to have done far better. Few policymakers were willing or able to do much to make schools safe, nor our communities at large. The story of suicidal behavior and school closures changes none of that.

•••

Suicide attempts and suicide deaths tell us something about the mental health of the population. But they do not tell us everything. In a future post, I’ll discuss child and adolescent mental health during the Covid-19 pandemic in general.

Please leave a comment below on this difficult subject.

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The number of COVID-19 cases surpassed 40 million on Saturday in Latin America and the Caribbean.

Since the first coronavirus infections were recorded last year, the number of cases in the region has reached 40,073,507, according to an AFP count based on official data as of 0200 GMT.

The number of deaths has reached 1,353,335.

The rapid spread of the highly contagious Delta variant has fueled a surge in COVID-19 cases around the world this week, with total cases hitting 192,942,266 with 4,143,687 deaths.

Source

Major news sites including The Washington Post, New York Magazine, and HuffPost, saw their stories now displaying porn videos instead of the once-embedded intended ones.

 

The fiasco happened as prominent websites relied on the domain vid.me to embed streaming videos in their articles.

 

The vid.me domain has been defunct for about four years and has had its ownership transferred over time to different parties.

For those who prefer to watch... 'Right in front of my salad?'

Websites of major news outlets such as The Washington Post, New York Magazine, and Huffpost, among others, shocked readers when their stories displayed NSFW videos, with no relevance to the story.

 

As seen by BleepingComputer today, unfortunately, some news sites are still stuck with this mess:

The incident, first reported by Motherboard, was spotted yesterday by a user DOXIE, who has shared many more examples in their Twitter thread:

 

How did this happen?

Essentially, the affected sites had been relying on the video streaming provider, Vidme, to embed streaming content.

 

To do so, websites would use HTML iframes to display the videos hosted on the vid.me domain:

However, Vidme has long been defunct. 

 

In 2017, Vidme shut down its operations with vid.me's homepage showing a farewell message:

A blog post followed stating Vidme had been acquired by Giphy. Any hosted videos were scheduled for deletion on December 15th, 2017.

 

In practice, this meant, those iframes embedding hosted videos would have ideally shown nothing or, maybe an error message under usual circumstances.

 

But, according to WHOIS results, vid.me domain's ownership and/or registration was updated sometime this month.

 

DOXIE hypothesized that the domain had expired and was taken over by a porn company, "5 Star HD Porn" which now redirects all vid.me links to the porn site.

 

As such, all of the websites previously embedding content from Vidme via iframes were now serving hardcore porn.

 

Some have cheekily surmised if this counts as a supply-chain incident.

 

5 Star HD Porn who now apparently owns the vid.me domain, did not respond to Motherboard's request for comment.

 

Suffice to say, if you were previously using Vidme to host content on your website, it makes sense to purge any and all links to the defunct service.

 

Readers who prefer to block content from this domain from appearing in unexpected places can add vid.me to their system's hosts file, as suggested by tech lawyer Neil Brown.

 

There's a tutorial on BleepingComputer explaining how to accomplish this. Adding the following line to your hosts file (without http://) should suffice:

 

127.0.0.1 vid.me

Major news sites serve porn after vid.me domain takeover

Archaeologists find ancient Egyptian warship sunk near Alexandria

The fast galley probably sank during an earthquake in the 100s BCE.

 

Twenty-four hundred years ago, Heraklion was ancient Egypt’s largest port on the Mediterranean Sea. Today, the ancient city lies submerged beneath Abu Qir Bay, a few kilometers off the coast of Alexandria. Archaeologists recently discovered the wreck of a warship from the city’s final years buried in the seabed for 2,100 years beneath five meters of clay and crumbled pieces of an ancient temple to the Egyptian god Amun.

A fast but unlucky warship

The outline of the wrecked ship suggests speed. Its 25 meter-long hull is about six times longer than it is wide, meaning that it was a long, sleek vessel built to race through the water. Clearly, this was no cargo vessel; ships built to haul cargo or passengers tend to be wider, built for capacity rather than speed and agility. The archaeologists from the European Institute for Underwater Archaeology who discovered the wreck say it was probably a warship, and its captain picked an unlucky day to tie up in the channel that flowed along the south side of the Temple of Amun in Heraklion.

 

Some of the city’s inhabitants called the place Heraklion; others called it Thonis, and archaeologists have found stone monuments inscribed with both names together. Coins and bits of pottery found among the city’s submerged ruins suggest that Thonis-Heraklion flourished from the 500s to the 300s BCE. When Alexander the Great founded Alexandria 32 kilometers to the southeast in 331 BCE, the new city replaced Thonis-Heraklion as Egypt’s largest Mediterranean port, and the older city began to decline.

 

By the 100s BCE, a series of earthquakes and tsunamis had battered the once-great city. One particularly severe quake caused the hard clay beneath Thonis-Heraklion to behave more like a liquid, and buildings all over the city collapsed. At the entrance to one canal, a cluster of Greek mortuary temples that had stood since the 300s crumbled. And the great Temple of Amun collapsed into the channel, raining huge blocks of carved stone onto the long, sleek warship tied up at a nearby wharf, according to Mustafa Waziri, the secretary-general of Egypt’s Supreme Council of Antiquities.

 

Archaeologists recently discovered the shipwreck using a sub-bottom profiler—a sonar instrument designed to look for objects buried beneath the sea floor, sort of like an acoustic version of ground-penetrating radar. It lay beneath five meters of clay and debris from the ruined Temple of Amun at the bottom of what was once a deep channel running through the ancient city. Now the channel is just a deeper, mud-filled area on the bottom of Abu Qir Bay, but the clay helped preserve the remains of the ancient warship.

Two ancient shipbuilding traditions join forces

“Finds of fast galleys from this period remain extremely rare,” said IEASM archaeologist Frank Goddio, who led the project. The Abu Qir Bay ship is only the second warship ever found from the last few centuries BCE—the Ptolemaic Period in Egypt and the era of the Punic Wars between Rome and Carthage. The other example is a Carthaginian warship dated to around 235 BCE. And the details of the Abu Qir Bay ship’s construction reveal one aspect of how Egyptian and Hellenistic cultures mixed in Ptolemaic Egypt.

 

Some of the techniques used in building the warship are clearly Greek, like the mortise-and-tenon joints (ones in which a tab from one piece of wood fits into a slot cut into the adjoining piece) that hold many of its timbers together. But other aspects of the ship’s design and construction are distinctly ancient Egyptian. Those clues, combined with some timbers that had evidently been salvaged and re-used from older ships, suggest that the warship was built somewhere in Egypt.

 

And the warship was clearly built for the Nile and the shallow channels of the river delta. Its flat bottom and keel (a heavy timber that runs the ship's length) are perfect for shallow water.

 

Other details of the shipwreck reinforce the notion that it was built for speed. Archaeologists found the ship’s mast step—the wooden structure that holds the base of a ship’s mast—still lying atop the keel, and they say it was clearly built for a large mast, capable of supporting a large sail. Rowers would have propelled the ship swiftly through the water anytime the wind wasn’t cooperating.

A sunken city

Archaeologists studying the sunken ruins of Thonis-Heraklion rely on ancient coins and distinctive types of pottery for information about the age of the layers they excavate. Most of those coins and ceramics date to the 500s to 300s BCE, but archaeologists almost never find anything newer than the 100s CE. Eerily, it’s like life here just stopped after the earthquake.

 

Historical records suggest that a few people stuck around through the next several centuries, although Thonis-Heraklion never regained anything like its former life. But by the 700s CE, sea-level rise and land subsidence had drowned the ruins of the ancient city, leaving it submerged in the shadow of the city that replaced it.

 

Thonis-Heraklion lay forgotten beneath Abu Qir Bay until 1933, when a Royal Air Force pilot flying over the bay looked down and saw ruins and debris beneath the water. In 1999, Goddio and his team relocated those ruins and began to survey and excavate them. So far, archaeologists have explored less than five percent of the ancient city.

Archaeologists find ancient Egyptian warship sunk near Alexandria

As one big international competition begins, another one is nearing its end. At least we hope so.

I am, of course, talking about the Tokyo Olympic Games and the international roll-out of vaccines against COVID-19.

Australia has been in the top ten in the medal tally at every summer Olympics since 1992. It is projected to again be near the top in Tokyo—certainly on a per-capita basis.

But in the vaccination standings, we are near the bottom of the OECD league.

When it comes to COVID vaccines, Australia has had a shocker. With apologies to the late legendary sports broadcaster Norman May, no one would be exclaiming: "Gold! Gold to Australia! Gold!"

Things are not going swimmingly. If this were a 4x100 meter medley relay, our team would involve the backstroker jumping into the diving pool, the breaststroker veering into the wrong lane, the butterfly swimmer breaking, and the freestyle anchor swimmer sinking.

Unlike other competitor countries, the Australian government failed to buy a broad portfolio of vaccines. It bet on two options—one being developed by the University of Queensland, the other by Oxford University and AstraZeneca—that could be made in Australia.

This has proven a mistake.

It didn't ramp up its mRNA vaccine purchasing until very late in the game. Bypassing state governments, it thought it could rely on GPs to deliver the vaccines without paying them properly or appreciating they have limited capacity, do other important things and don't always have the specialist freezers required to store mRNA vaccines.

Australia's administrative state

Australians seemed to have been surprised by the incompetence of our vaccine purchasing strategy and roll-out. With the lockdowns in Sydney, Melbourne and now Adelaide exposing the folly of Prime Minister Scott Morrison's declaration in March that vaccination "is not a race", his approval rating has slumped to its lowest since the pandemic began.

We generally trust our governments—federal, state and local—to do most things reasonably well. Indeed, compared to the rest of the world the "administrative state" in Australia works incredibly well.

From getting a drivers' license to being treated in a public hospital, enrolling a child in school or obtaining government benefits and assistance, things tend to just "work." Kind of like an Apple product.

Even in wealthy countries with excellent rule of law this is not always the case. Ask anyone who has gone to the Department of Motor Vehicles in a major US city.

Australia's administrative state is built on the hard work and common sense of those who work in the public sector. It has a proud track record.

So why has the vaccination roll-out been so botched? Was it just bad luck? Or are there broader lessons?

More than just luck

Well, bad luck played a role.

The UQ vaccine did look promising, making it to phase 1 clinical trials before it was discovered it produced results falsely suggesting recipients had HIV. It is still in "redevelopment".

Australia wins the Men’s 4x100 meter medley relay at the 1980 Olympics.

AstraZeneca has been associated with a small risk of blood clotting, which has shaken public confidence, and led the governent's health advisers to recommend it only for those those aged 60 or older.

This is why smart investors don't put all their eggs in one—or two—baskets. They diversify.

There was a lot more to our vaccine bungles than bad luck. How things turned out depended in large part on what government did. To paraphrase an old golfing saying, the harder you work, the luckier you get.

Three lessons

There are three lessons from the vaccination debacle.

First, the public service is full of great people, but the capacity of government departments has been systematically downgraded over the past few decades.

Both sides of politics must share some of the blame. If we as citizens are appalled by the performance of a health official, then we have to look beyond the person to the office. How did he or she end up there?

Second, far too much of government at a federal level is seen through a purely partisan political lens.

States governments, which live or die largely on the quality of service delivery, are often much better in this regard. Sure, Victorian premier Dan Andrews and his NSW counterpart Gladys Berejiklian are good politicians. But their biggest political asset is their track record in delivering for their states.

Third, short-termism in government thinking is a big problem.

Short-term thinking dulls the powerful electoral incentives that (at least partly) drive politicians to perform. As any economist will tell you, people respond to incentives. But political incentives don't seem to be working very well these days. If voters think short-term, so will politicians.

We  don't necessarily need to demand more of government. We should insist political leaders act as if they care about the future —of the country, and the planet—rather than just the next election.

Yes, this is a race

Make no mistake: Australia's response to the pandemic is a competition.

It's a competition for international investment, skilled migrants, tourists and students. It's a competition to provide a supportive environment for business, a well-functioning environment for consumers, and a safe environment for citizens and visitors.

And we're losing. Badly.

Perhaps watching the Olympics over the next couple of weeks will give our leaders a patriotic shot in the arm, and inspire them to give the rest of the vaccination race their best.

We are counting on them.

Source

Researchers are observing a new long-term health concern in patients hospitalized with COVID-19—an increase in new-onset hyperglycemia lasting months after infection. An Italian study found that about half of the patients admitted to the hospital for COVID-19 during the start of the pandemic had new cases of hyperglycemia, or high levels of blood sugar. They also had poorer outcomes.

"These people were not diabetic before," says lead author Paolo Fiorina, MD, Ph.D., who is affiliated with the Division of Nephrology at Boston Children's Hospital. "But during admission, about 46 percent of the patients were found to have new hyperglycemia." While most cases resolved, about 35 percent of the newly hyperglycemic patients remained so at least six months after the infection.

Hyperglycemia persisted beyond infection

The study assessed the health of 551 people admitted to the hospital in Italy from March through May 2020. A follow-up period included six months after hospital admission.

Compared with patients with no signs of glucose abnormalities, the hyperglycemic patients also had worse clinical concerns:

• longer hospitalizations
• worse clinical symptoms
• a higher need of oxygen
• a higher need of ventilation
• more need of intensive care treatment

"We wanted to understand the mechanism why these patients did poorly compared to those who did not have hyperglycemia," says Fiorina, who published an earlier paper showing COVID-19 worsened glucometabolic control in diabetics. The current study was published in Nature Metabolism.

Hormones also out of balance

To learn more, all patients were fitted with a glucose sensor at admission. Over the course of time, the researchers detected many abnormalities in glucose metabolic control in the hyperglycemic patients.

They also found that hyperglycemic patients had abnormal hormonal levels. "We discovered they were severely hyperinsulinemic; they produced too much insulin," says Fiorina. They also had abnormal levels of pro-insulin, a precursor of insulin, and markers of impaired islet beta cell function. Islet beta cells make and secrete insulin.

"Basically, the hormonal profile suggests that the endocrine pancreatic function is abnormal in those patients with COVID-19 and it persists long after recovery," he says.

Inflammation from excess cytokines

Hyperglycemic patients also had severe abnormalities in the amount of inflammatory cytokines, including IL-6 and others.

"We thought that blocking IL-6, and potentially even other cytokines, would be a benefit for beta cell function," adds Fiorina, whose theory was proven true. Patients treated with anti-IL-6 therapy (tocilizumab), had greater improvement in glycemic control higher compared with those who did not receive the medication.

A coming wave of diabetic patients?

While glucometabolic abnormalities declined over time in some patients—particularly after COVID-19 infection—other issued remained. Many patients had higher post-prandial (after eating) glucose levels and abnormal pancreatic hormones in the post-COVID-19 period.

"This study is one of the first to show that COVID-19 has a direct effect on the pancreas," says Fiorina. "It indicates that the pancreas is another target of the virus affecting not only the acute phase during hospitalization but potentially also the long-term health of these patients."

The study points to the importance of evaluating pancreatic function in patients hospitalized for COVID-19—while in the hospital and over the long term. "This goes beyond fasting glucose testing because we observed glucose metabolic abnormalities during the day which were not always present in a normal fasting test," says Fiorina.

In terms of treatment, questions remain about how to care for patients with COVID-19-related glucose abnormalities. Should patients be treated just with an anti-diabetic drug like an insulin sensitizer, or should anti-inflammatory drugs like tocilizumab and other drugs be used?

"If you keep targeting and blocking insulin, but you have a strong and chronic inflammation, it may lead to chronic damage," says Fiorina, who suggests larger studies need to be done to test anti-diabetic and anti-inflammatory treatment. "When you consider how many patients have been hospitalized with COVID-19, and continue to be worldwide, we may see a huge increase in the diabetic population."

Source

Imagine if we could use strong electromagnetic fields to manipulate the local properties of spacetime—this could have important ramifications in terms of science and engineering.

Electromagnetism has always been a subtle phenomenon. In the 19th century, scholars thought that electromagnetic waves must propagate in some sort of elusive medium, which was called aether. Later, the aether hypothesis was abandoned, and to this day, the classical theory of electromagnetism does not provide us with a clear answer to the question in which medium electric and magnetic fields propagate in vacuum. On the other hand, the theory of gravitation is rather well understood. General relativity explains that energy and mass tell the spacetime how to curve and spacetime tells masses how to move. Many eminent mathematical physicists have tried to understand electromagnetism directly as a consequence of general relativity. The brilliant mathematician Hermann Weyl had especially interesting theories in this regard. The Serbian inventor Nikola Tesla thought that electromagnetism contains essentially everything in our universe. So what is the mutual relationship of electromagnetism and gravitation? We provide one possible explanation to the riddle.

Maxwell's equations and general relativity—what are these all about?

Maxwell's equations are the key linear partial differential equations that describe classical electromagnetism. The equations relate the electromagnetic field to currents and charges. On the other hand, in general relativity, the Einstein field equation is a set of nonlinear partial differential equations describing how the metric of spacetime evolves, given some conditions, such as mass density in the spacetime. Both equations are ultimately of second order, if seen properly.

Therefore, we thought that perhaps we are talking about the same governing equation, which could describe both electromagnetism and gravitation. Indeed, it becomes clear that Maxwell's equations hide inside the Einstein field equations of general relativity. The metric tensor of spacetime tells us how lengths determine in spacetime. The metric tensor also thus determines the curvature properties of spacetime. Curvature is what we feel as "force." In addition, energy and curvature relate to each other through the Einstein field equations. Test particles follow what are called geodesics—the shortest paths in the spacetime.

The missing link

The link between general relativity and electromagnetism becomes clear by assuming that the so-called four-potential of electromagnetism directly determines the metrical properties of the spacetime. In particular, our research shows how electromagnetism is an inherent property of spacetime itself. In a way, spacetime itself is therefore the aether. Electric and magnetic fields represent certain local tensions or twists in the spacetime fabric. Our research shows that the Lagrangian of electrodynamics is just the Einstein-Hilbert action of general relativity; it reveals how Maxwell's equations of electromagnetism are an optimality condition for the metric of spacetime to be sufficiently flat. As Einstein's theory of general relativity provides that the metric is optimal in a sense, electromagnetism is hidden in the nonlinear differential equations of general relativity. On the other hand, this means that general relativity is a generalized theory of nonlinear electromagnetism.

Geometrization of the material world

John Wheeler, the famous physicist, put forward the idea that all of the material world is constructed from the geometry of the spacetime. Our research strongly supports this kind of natural philosophy. It means that the material world always corresponds to some geometric structures of spacetime. Tensions in spacetime manifest themselves as electric and magnetic fields. Moreover, electric charge relates to some compressibility properties of spacetime. Electric current seems to be a re-balancing object, which transports charge in order to keep the spacetime manifold Ricci-flat. This is aesthetically pleasing, as nature seems to strive for harmony, efficiency and simplicity.

Riemann curvature tensor is more than just Ricci curvature—electromagnetic fields stretch and bend the spacetime

Although our theory shows that Maxwell's equations are a condition for the spacetime to be Ricci-flat, electromagnetic fields do seem to cause special curvature in spacetime nevertheless. The relevant curvature is what is known in differential geometry as the Weyl curvature. Weyl curvature in spacetime is the local curving of spacetime in such a way that locally, volumes are preserved. It is a special kind of stretching and bending of spacetime.

Conclusions

We believe that empirical research on this topic is important. This means measuring the local curvature of spacetime when there are strong electromagnetic fields present. Perhaps one could use, e.g., superconducting coils and laser light to measure any deviations in the fabric of spacetime. Artificial modifying of spacetime could have extensive benefits in the field of engineering, for example.

Finally, it is worth mentioning that our approach has the benefit of simplicity—we do not need extra dimensions, torsion tensors, asymmetric metric tensors or the like.

Source

“So please, remember this. Remember that when traveling through Yosemite, we are all just visitors in the home of countless animals and it is up to us to follow the rules that protect them,” wrote the park ranger who discovered the dead cub.

A park ranger from Yosemite National Park wrote a compelling post on Facebook recounting how a mama bear in despair would not leave her cub when it was hit and killed by a car. He now urges visitors to drive the speed limit and be 'alert' in order to protect the park's wildlife population.

The ranger, who did not want to be identified, detailed his experience of retrieving the lifeless 6-month-old cub off the road and watching his mother call for her baby, Today reported.

“I pick up the cub — it couldn’t be much more than 25 pounds — and begin carrying it off into the woods. I have no certain destination; I’m just walking until I can no longer hear the hiss of the road behind me. I see a grassy spot surrounded by a semi-ring of down logs and gravitate towards it. The least I can do is find it a nice place to be laid,” wrote the ranger.

When he began to log the incident and discovered the cub was a female, he wrote  “it triggered thoughts of the life this bear may have lived — perhaps she would have had cubs of her own.”

The ranger then recounted what he described as “deep-toned but soft sounding grunts,” the mama bear made. 

“I immediately know what it is. It’s a vocalization, the kind sows (female bears) make to call to their cubs. I turn and look in its direction and there she is, the same bear from before intently staring back at me. It’s no coincidence. I can feel the callousness drain from my body. This bear is the mom, and she never left her cub,” he wrote.

The ranger, who watched the mama bear dart back and forth several times on the road, in hopes of waking her baby girl, described his emotion.

"My heart sinks," he said. "It’s been nearly six hours and she still hasn’t given up on her cub,” he wrote. “I glance back finding myself hoping it would respond to her call too, but of course, nothing. Now here I am, standing between a grieving mother and her child. I feel like a monster.”

In that moment of despair, the ranger set up a remote camera so he would be able to show how critical it is for visitors who visit Yosemite to drive the speed limit and to protect the park’s black bear population. 

“Every year we report the number of bears that get hit by vehicles, but numbers don’t always paint a picture. I want people to see what I saw: the sad reality behind each of these numbers,” he wrote.

“So please, remember this. Remember that when traveling through Yosemite, we are all just visitors in the home of countless animals and it is up to us to follow the rules that protect them. Go the speed limit, drive alertly, and look out for wildlife. Protecting Yosemite’s black bears is something we can all do.”

The caring ranger also left a link for those who want to learn more at http://keepbearswild.org/vehicle-bear-collisions/.

Source

Linux Foundation Training & Certification is thrilled to announce that we are partnering with Women Who Code (WWCode), an international community dedicated to inspiring women to succeed in technology, to provide scholarships to promising women to help them get started working with open source software. 

WWCode will award 50 scholarships per quarter to deserving women, with Linux Foundation Training & Certification providing each of these recipients with a voucher to register for any Linux Foundation eLearning course and certification exam at no charge, such as the Linux Foundation Certified IT Associate, Certified Kubernetes Administrator, Linux Foundation Certified System Administrator and more. 

All Linux Foundation certification exams are conducted online with a proctor monitoring virtually via webcam and screen sharing.

Scholarship recipients will have one year to sit for their exam, and should they fail to pass on the first attempt, one retake will be provided. Upon passing a certification exam, they will receive a PDF certificate and a digital badge which can be displayed on digital resumes and social media profiles, and which can be independently verified by potential employers. 

“Open source technology is leading so much digital transformation today, from cloud computing to networking, web development, blockchain and more, yet there is a continual shortage of qualified talent generally, and fewer women pursuing these roles specifically,” said Linux Foundation SVP & GM of Training & Certification Clyde Seepersad. “At the same time, despite so much opportunity, barriers to entry and simply figuring out where to start can be daunting. We hope that this program makes it easier for many women to launch successful open source careers, and go on to inspire the next generation of developers, DevOps engineers, cloud architects and more.”

“Continuous learning is one of the cornerstones of tech industry leadership and success for diverse women,” said WWCode CEO Alaina Percival. “We are proud to be partnering with The Linux Foundation to provide these invaluable scholarship opportunities to our global community.”

Those interested in applying for a Women Who Code/Linux Foundation scholarship can do so here.

About Women Who Code

Women Who Code (WWCode) is an international nonprofit dedicated to inspiring women to excel in technology careers. WWCode is building a world where women are proportionally representative as technical leaders, executives, founders, VCs, board members, and software engineers. The organization has executed more than 14,000 free events around the world, garnered a membership exceeding 290,000 in 134 countries. Help empower even more women to advance in tech with the training and community they need to succeed by supporting WWCode. Learn more at womenwhocode.com.

The post Women Who Code and Linux Foundation Launch Open Source Scholarship appeared first on Linux Foundation – Training.

Source

Sydney's fast-growing coronavirus outbreak has become a "national emergency," state leaders said Friday, as Australia's largest city reported another record number of new infections.

Admitting a month-long lockdown had so far failed to stop a Delta-variant outbreak, the state of New South Wales pleaded for Canberra to urgently send more vaccines and resources.

Declaring the outbreak a national emergency could pave the way for more federal government involvement in stemming the crisis.

"We have an obligation on behalf of the nation to contain the virus," said New South Wales premier Gladys Berejiklian. "There is no doubt that the numbers are not going in the right direction."

Her state on Friday reported 136 new cases, a record for this outbreak, which now totals 1,782.

With the virus "spreading everywhere" and half the country's 25 million people currently in lockdown, Berejiklian said the government must "refocus" its glacial vaccine rollout.

Just 12 percent of Australians have been fully vaccinated, thanks to problems with supplies of Pfizer jabs and scepticism about the safety of the AstraZeneca vaccine.

"We need, at least, more first doses of Pfizer," Berejiklian said, while warning Sydney's five million residents that restrictions could run until October.

She also announced non-essential workers in specific areas of Sydney would now be barred from leaving, tightening a lockdown that is almost certain to be formally extended next week.

"It is fairly apparent that we will not be close to zero (cases) next Friday," Berejiklian said. "We will have a clearer view next week on what August, September, and October look like."

Prime Minister Scott Morrison on Thursday apologised for the country's slow vaccine rollout, admitting targets had not been met.

"I take responsibility for the vaccination programme. I also take responsibility for the challenges we've had," he said. "Obviously, some things are within our control, some things that are not."

'Ring of steel'

With Sydney cases spiralling, the premier of Victoria state, Dan Andrews, called for a "ring of steel" to be thrown up around the city, banning any travel in or out.

In New Zealand, Prime Minister Jacinda Ardern announced a travel bubble between the two countries would be suspended for at least eight weeks.

Australians will no longer have quarantine-free entry to New Zealand, while return flights would be arranged for New Zealanders in Australia.

"There are now multiple outbreaks, and in differing stages of containment, that have forced three states into lockdown," Ardern said.

"The health risk to New Zealanders from these cases is increasing... now is the time for a suspension to ensure New Zealanders aren't put at undue risk from COVID-19 and to ensure we retain our hard-won gains."

Quarantine-free travel between New Zealand and Australia began in April after more than a year of closed borders and was hailed by tourism operators as a "saviour for businesses".

However, New Zealand has several times since halted the bubble with individual states and territories as outbreaks erupted in Australia.

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It depends on your situation, but masking in public can provide another layer of protection and help prevent the virus from spreading to others who aren't protected.

An easing of safety precautions and the large number of people who remain unvaccinated in many regions are contributing to the spread of cases around the world.

The U.S. Centers for Disease Control and Prevention has not changed its advice that fully vaccinated people can safely go without masks in most situations. But Dr. Rochelle Walensky, the agency's director, said local decisions on mask mandates could vary depending on vaccination levels and whether there's a surge.

Los Angeles County recently started requiring residents to wear masks indoors regardless of vaccination status, for example, and officials in New Orleans are urging people to do the same.

Though COVID-19 vaccines greatly reduce the chance of severe illness and death and remain effective against variants, some experts said wearing a mask is a reasonable precaution since it's still possible to get infected.

Masking could also help prevent the spread of the virus to children too young for vaccination and people with weak immune systems.

"Personally, I continue to wear a mask when going into public spaces outside of my household, both for my own protection and for the sake of my community," said virus researcher Angela Rasmussen of the Vaccine and Infectious Disease Organization at the University of Saskatchewan.

Dr. William Schaffner, an infectious disease expert at Vanderbilt University, said a "belt-and-suspenders" approach also makes sense for people who are older or have health issues and are more vulnerable to getting severely ill if infected.

"I'm pretty healthy, but I do have gray hair. So when I go out to the supermarket, I'm masked," Schaffner said.

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Shares of Indian food delivery giant Zomato soared on its market debut Friday, following a 93.75 billion rupee ($1.3 billion) IPO, the country's biggest this year.

Around 30 Indian companies have announced plans to list shares this year, with start-ups attracting billions of dollars in investment even though many are yet to make a profit.

Zomato, which counts subsidiaries of Chinese tycoon Jack Ma's Ant Group and Uber among its shareholders, dominates India's booming app-based food-delivery space alongside rival Swiggy.

Its shares debuted at 115 rupees on the Bombay Stock Exchange's Sensex Index, 51 percent higher than its issue price after its IPO was subscribed 40.38 times at the end of last week.

The stock then rocketed up 80 percent in the opening 10 minutes, taking Zomato's market capitalisation across the one trillion rupee mark.

India's economy has taken a battering during the pandemic, recording its worst annual recession since independence in 1947. But its start-up sector has been a rare bright spot.

This year alone, around 20 "unicorns"—firms valued at more than a billion dollars—have been created, including half a dozen in four days in April.

Many are struggling to recruit qualified employees, with some reportedly offering incentives such as free motorbikes and tickets to cricket matches to lure talent.

This year is set to be India's best for IPOs. Others set to list include digital payments firm Paytm, backed by Japan's SoftBank and Ma.

Many of the start-ups, though, are loss-making.

Zomato for instance, which operates in 525 Indian cities, is yet to turn profitable and reported a loss of 8.16 billion rupees in the financial year ending March 2021.

"We are going to relentlessly focus on 10 years out and beyond, and are not going to alter our course for short-term profits at the cost of long-term success of the company," Zomato's chief executive Deepinder Goyal said Friday.

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Google turns AlphaFold loose on the entire human genome

The AI-driven structural predictions are being shared through a public database.

Just one week after Google's DeepMind AI group finally described its biology efforts in detail, the company is releasing a paper that explains how it analyzed nearly every protein encoded in the human genome and predicted its likely three-dimensional structure—a structure that can be critical for understanding disease and designing treatments. In the very near future, all of these structures will be released under a Creative Commons license via the European Bioinformatics Institute, which already hosts a major database of protein structures.

 

In a press conference associated with the paper's release, DeepMind's Demis Hassabis made clear that the company isn't stopping there. In addition to the work described in the paper, the company will release structural predictions for the genomes of 20 major research organisms, from yeast to fruit flies to mice. In total, the database launch will include roughly 350,000 protein structures.

What’s in a structure?

We just described DeepMind's software last week, so we won't go into much detail here. The effort is an AI-based system trained on the structure of existing proteins that had been determined (often laboriously) through laboratory experiments. The system uses that training, plus information it obtains from families of proteins related by evolution, to predict how a protein's chain of amino acids folds up in three-dimensional space.

 

The three-dimensional structure that results can give us critical information about the protein, such as how it interacts with other proteins and chemicals and where on the protein chemical reactions occur. Using the structure, researchers can learn how specific mutations, like the ones that cause genetic diseases, alter the protein's function. Researchers can also use the structure to design chemicals that can interact with the protein and change its function, something that has led to therapies for various cancers and HIV.

 

Normally, these structures are determined by isolating the protein, preparing it for imaging, and bombarding it with electrons. These techniques are difficult and time-consuming, and they often fail. The paper estimates that decades of lab work have left us with structural information for only 17 percent of the full set of human proteins.

 

That explains why researchers have also spent decades looking for ways to predict structures for proteins using nothing but the sequence of amino acids that make them up. But prior to AlphaFold, the accuracy of software wasn't high enough to be consistently useful.

The human protein collection

DeepMind didn't attempt to predict the structure of every protein in the human genome; some are simply too large to be handled conveniently. (The company set the size cutoff at 2,700 amino acids, which is unfortunately smaller than a gene I spent a chunk of my post-doc cloning.) But most proteins are far smaller than that, so the final count is 98.5 percent of the expected proteins in the genome. Some of these proteins are only predicted to exist based on features of DNA sequences within the human genome.

 

Just as importantly, AlphaFold includes a confidence estimate that registers how likely its predictions are to be accurate. All told, the software is confident about the location of about 60 percent of the amino acids it has predicted, and it's highly confident about a bit over a third. Put differently, the researchers have a confident prediction about most of the structure of 40 percent of human proteins. Obviously, that means there's a considerable amount of work to do before we can say we have a good grip on the full set of human proteins. But that's still a lot more than the 18 percent we have actual structures for.

 

There is also a large collection of proteins that aren't well-represented by existing structures. Those embedded in a cell's membrane are difficult to isolate and work with, so researchers haven't solved many structures of these membrane proteins. But despite having fewer examples in its training data, AlphaFold seems to handle the structures reasonably well.

 

Where does the system run into problems? Many proteins simply don't form a defined structure—in fact, their function seems to depend on having a completely flexible structure in order to function. Obviously, it's hard to make any accurate predictions of a structure here, since these proteins (more typically, sections of proteins) have none. There are also many proteins that only take on their structure when they are in contact with another protein or a chemical. Since AlphaFold doesn't have that information, there is not a lot it can do.

 

In general, the DeepMind team found that AlphaFold had very low confidence in its predictions for disordered regions, and they could use that information to identify areas of proteins that are likely to be unstructured.

It’s all going public

At some point in the near future (possibly by the time you read this), all this data will be available on a dedicated website hosted by the European Bioinformatics Institute, a European Union-funded organization that describes itself in part as follows: "We make the world’s public biological data freely available to the scientific community via a range of services and tools." The AlphaFold data will be no exception; once the above link is live, anyone can use it to download information on the human protein of their choice.

 

Or, as mentioned above, the mouse, yeast, or fruit fly version. The 20 organisms that will see their data released are also just a start. DeepMind's Demis Hassabis said that over the next few months, the team will target every gene sequence available in DNA databases. By the time this work is done, over 100 million proteins should have predicted structures. Hassabis wrapped up his part of the announcement by saying, "We think this is the most significant contribution AI has made to science to date." It would be difficult to argue otherwise.

 

That said, there are still some issues left to be worked out. There will undoubtedly be improvements made to the algorithm with time, so there will need to be a system to handle updating and versioning in the main database. DeepMind has also made the code for AlphaFold open source, so there's the potential for forks and other complications.

 

But those problems are worries for the future. For now, we can all sit back and watch the servers strain to service nearly every biologist on the planet who is curious to see whether a protein that interests them has a high-quality structure.

 

(Except your humble author, since my protein of choice was annoyingly oversized.)

 

Nature, 2021. DOI: 10.1038/s41586-021-03828-1 (About DOIs).

Google turns AlphaFold loose on the entire human genome

The body's so-called good cholesterol may be even better than we realize. New research from Washington University School of Medicine in St. Louis suggests that one type of high-density lipoprotein (HDL) has a previously unknown role in protecting the liver from injury. This HDL protects the liver by blocking inflammatory signals produced by common gut bacteria.

The study is published July 23 in the journal Science.

HDL is mostly known for mopping up cholesterol in the body and delivering it to the liver for disposal. But in the new study, the researchers identified a special type of HDL called HDL3 that, when produced by the intestine, blocks gut bacterial signals that cause liver inflammation. If not blocked, these bacterial signals travel from the intestine to the liver, where they activate immune cells that trigger an inflammatory state, which leads to liver damage.

"Even though HDL has been considered 'good cholesterol,' drugs that increase overall HDL levels have fallen out of favor in recent years because of clinical trials that showed no benefit in cardiovascular disease," said senior author Gwendalyn J. Randolph, Ph.D., the Emil R. Unanue Distinguished Professor of Immunology. "But our study suggests that raising levels of this specific type of HDL, and specifically raising it in the intestine, may hold promise for protecting against liver disease, which, like heart disease, also is a major chronic health problem." In the study, the researchers showed that HDL3 from the intestine protects the liver from inflammation in mice.

Any sort of intestinal damage can impact how a group of microbes called Gram-negative bacteria can affect the body. Such microbes produce an inflammatory molecule called lipopolysaccharide that can travel to the liver via the portal vein. The portal vein is the major vessel that supplies blood to the liver, and it carries most nutrients to the liver after food is absorbed in the intestine. Substances from gut microbes may travel along with nutrients from food to activate immune cells that trigger inflammation. In this way, elements of the gut microbiome may drive liver disease, including fatty liver disease and liver fibrosis, in which the liver develops scar tissue.

Randolph became interested in this topic through a collaboration with two Washington University surgeons, Emily J. Onufer, MD, a surgical resident, and Brad W. Warner, MD, the Jessie L. Ternberg Ph.D., MD, Distinguished Professor of Pediatric Surgery and chief surgeon at St. Louis Children's Hospital, both co-authors on the study. Some premature infants develop a life-threatening condition called necrotizing enterocolitis, an inflammation of the intestine that can require a portion of the intestine to be surgically removed.

Even after a successful bowel surgery, such babies often develop liver disease, and Onufer and Warner wanted to understand why.

"They were studying this problem in a mouse model of the condition: They remove a portion of the small intestine in mice and study the liver fibrosis that results," Randolph said. "There were hints in the literature that HDL might interfere with lipopolysaccharide's detection by immune cells and that the receptor for lipopolysaccharide might be linked to liver disease following the bowel surgery.

"However, no one thought that HDL would directly move from the intestine to the liver, which requires that it enter the portal vein," she said. "In other tissues, HDL travels out through a different type of vessel called a lymphatic vessel that, in the intestine, does not link up to the liver. We have a very nice tool in our lab that lets us shine light on different organs and track the HDL from that organ.

So, we wanted to shine light on the intestine and see how the HDL leaves and where it goes from there. That's how we showed that HDL3 leaves only through the portal vein to go directly to the liver."

As the HDL3 makes this short journey down the portal vein, it binds to a protein called LBP—lipopolysaccharide binding protein—which binds to the harmful lipopolysaccharide. When the harmful lipopolysaccharide is bound to this complex, it is blocked from activating immune cells called Kupffer cells. These are macrophages that reside in the liver and, when activated by lipopolysaccharide, can drive liver inflammation.

As a complex of proteins and fats, HDL3 uses its partnership with LBP to bind to lipopolysaccharide. When LBP is part of the HDL3 complex, it prevents the harmful bacterial molecule from activating the liver Kupffer cells and inducing inflammation, according to experiments conducted by first author Yong-Hyun Han, Ph.D., when he was a postdoctoral researcher in Randolph's lab. Han is now on the faculty of Kangwon National University in South Korea.

"We think that LBP, only when bound to HDL3, is physically standing in the way, so lipopolysaccharide can't activate the inflammatory immune cells," Han said. "HDL3 is essentially hiding the harmful molecule. However, if LBP is binding to lipopolysaccharide and HDL3 is not present, LBP is not able to stand in the way. Without HDL3, LBP is going to trigger stronger inflammation."

The researchers showed that liver injury is worse when HDL3 from the intestine is reduced, such as from surgical removal of a portion of the intestine.

"The surgery seems to cause two problems," Randolph said. "A shorter intestine means it's making less HDL3, and the surgery itself leads to an injurious state in the gut, which allows more lipopolysaccharide to spill over into the portal blood. When you remove the part of the intestine that makes the most HDL3, you get the worst liver outcome. When you have a mouse that cannot genetically make HDL3, liver inflammation is also worse. We also wanted to see if this dynamic was present in other forms of intestinal injury, so we looked at mouse models of a high-fat diet and alcoholic liver disease."

In all of these models of intestinal injury, the researchers found that HDL3 was protective, binding to the additional lipopolysaccharide released from the injured intestine and blocking its downstream inflammatory effects in the liver.

The researchers further showed that the same protective molecular complexes were present in human blood samples, suggesting a similar mechanism is present in people. They also used a drug compound to increase HDL3 in the intestines of mice and found it to be protective against different types of liver injury. While the drug is only available for animal research, the study reveals new possibilities for treating or preventing liver disease, whether it stems from damage to the intestine caused by high-fat diets, alcohol overuse or physical injury, such as from surgery.

"We are hopeful that HDL3 can serve as a target in future therapies for liver disease," Randolph said. "We are continuing our research to better understand the details of this unique process."

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While humans have been struggling to control the Covid-19 pandemic, baking in record heat, and trying to figure out how not to run out of water, our spacecraft on Mars have been enjoying a rather more tranquil existence. (Not needing to breathe helps.) Parked on the Martian surface, the InSight lander is listening for marsquakes, while the Perseverance rover is rolling around in search of life.

 

This week, scientists are dropping an Olympus Mons of findings from the two brave robots. In three papers published today in the journal Science—each authored by dozens of scientists from around the world—researchers detail the clever ways they used InSight’s seismometer to peer deep into the Red Planet, giving them an unprecedented understanding of its crust, mantle, and core. It’s the first time scientists have mapped the interior of a planet other than Earth. And yesterday, another group of scientists held a press conference to announce early research results from Perseverance, and the next steps the rover will take to explore the surface of Jezero Crater, once a lake that could have been home to ancient microbial life.

 

Scientists still have a lot to learn about the Red Planet. “It's built from similar building blocks as our own planet, but Mars looks very different,” says University of Cambridge global seismologist Sanne Cottaar, who penned a perspective paper in Science on the three new studies. “There's lots of evidence that its evolution has been very different. And now forming this image of the layering of the planet will give us the tools to work out how this formed, how Mars came to be.”

 

Curiosities abound when comparing the two. Why, for instance, does Earth have a magnetic field, but Mars’ seems to have disappeared? Why are so many volcanoes spread all over Earth, while volcanoes are more localized—and bigger—on Mars? (At 374 miles in diameter and 16 miles high, Olympus Mons is the biggest known volcano in the solar system.) Its formation must have been cataclysmic, but the surface of Mars is now quiet; unlike Earth, it doesn’t seem to be volcanically active. (In May, though, scientists presented evidence of what they say is recent activity.) Only by peeking under the surface can scientists better understand these planetary oddities—and in doing so, better understand Earth’s own quirks as a fellow rocky planet.

 

But before we dive into today’s avalanche of scientific literature, we need a crash course on the workings of both Mars and its InSight observer. Compared to Earth, the Red Planet is geologically quite calm. Because our planet has plate tectonics—huge slabs of land that shift over the underlying mantle—the surface is positively popping with activity like volcanoes and catastrophic earthquakes. Mars lacks plate tectonics; it doesn’t have a plated surface, because its core formed and cooled off rapidly during its early days. Today it shakes with much smaller quakes that may come from the contracting of the planet as it continues to cool.

 

The InSight lander’s job is to detect these quakes with its seismometer, which it’s been doing since February 2019. The instrument provides scientists with extremely rich seismic data on two phenomena in particular: the P-waves and S-waves that marsquakes produce. “P-waves are compressional waves, like sound in air, and they are the fastest waves that we see moving through any planetary body,” says University of Cologne seismologist Brigitte Knapmeyer-Endrun, lead author on the paper that modeled Mars’ crust. “And then we have the secondary waves, the S-waves, the shear waves. The motion is more like if you pluck a string on a guitar and it swings.”

 

Critically, these S-waves are slower than P-waves, so when a quake pops off, they arrive at InSight’s seismometer a bit later. “This difference between the arrival of the P and S waves can give you an idea about what's the location of the quake; how far it was away from your station,” says Knapmeyer-Endrun. The waves also differ in what mediums they can travel through, versus which ones they bounce off of. P-waves move through solids, liquids, and gases, while S-waves only travel through solids.

 

By analyzing the waves that reach InSight’s seismometer, scientists can get an idea of the composition of Mars’ insides. Since S-waves can’t travel through the liquid core, all of their energy bounces off the boundary between core and mantle. Think of it like binary code for computers: Just as two elements—ones and zeros—can combine to produce extremely complex programming, so too can two kinds of waves combine to produce a sophisticated picture of the Red Planet’s guts. “We also look at differences in arrival times, and then we can say, ‘OK, this tells us something about the thickness of the layer,’” says Knapmeyer-Endrun.

 

Using this technique, she and her colleagues were able to estimate the thickness of the crust. Previously, scientists had used satellites flying overhead to measure the differences in gravity and topography across the planet, and they had taken a stab at the crust’s thickness that way, landing on an estimate of a global average of 110 kilometers. “Now, with our measurements from inside, we can say that that's definitely too much,” says Knapmeyer-Endrun. They now think the maximum figure for average thickness is 72 kilometers.

 

The researchers reckon that the crust is made of two or three layers. There’s a topmost layer that’s 10 kilometers thick, which InSight’s measurements revealed to be unexpectedly light, perhaps because it’s made of fractured rock left over from meteorite impacts. The layer below that goes down to about 20 kilometers. “Unfortunately, we are not sure what follows next, if it’s already the mantle or if we have a third layer in the crust. There’s some ambiguities that we haven’t resolved,” says Knapmeyer-Endrun. “We can definitely say that the crust is not as thick as has been predicted previously, and it has a lower density.”

Planetary seismologist Simon Stähler of ETH Zürich led the effort to characterize the hottest and innermost chunk of Mars’ interior—its core. Though they lack the ability to actually see inside the planetary center, Stähler’s team was able to extract some information just by analyzing the S-waves that bounce off the core-mantle boundary. These rumblings, unable to penetrate the liquid core, find their way back up to the Martian surface, where they are picked up by InSight’s receivers. “It takes a good 10 minutes,” Stähler says, from the time of the quake to the detection of the signal reflected by the core. By measuring this interval, his team was able to deduce how deep into the planet the waves are traveling, thus measuring the depth of the core itself: around 1,550 kilometers from the surface.

The researchers found the core density to be surprisingly low, at only about 6 grams per cubic centimeter, which is much lower than what they’d expected of an iron-rich center. “It’s still a bit of a mystery how the core is so light,” Stähler says. There must be lighter elements present, though exactly what those may be is unclear. He and his team eventually hope to detect P-waves produced by a marsquake originating directly across the planet from where InSight is parked. Since they can pierce through the core-mantle boundary, they will carry information about the core’s composition to the lander's receiver. But for that to happen, Stähler says, “Mars has to play along and give us this one quake on the other side of the planet.”

 

In Stähler’s team’s paper, they report a core radius of 1,830 kilometers. Another team, led by ETH Zürich geophysicist Amir Khan, found that this size is so large it leaves little room for an Earth-like lower mantle, a layer that acts as a heat-trapping blanket around the core. Earth’s mantle is divided into two parts, with a so-called transition zone in between; the upper and lower levels are composed of different minerals. “The mantle of Mars is—can I say flippantly—a slightly simpler version of the mantle of Earth, simply in terms of the mineralogy,” says Khan, lead author on the paper describing the mantle.

 

Previous estimates of the core’s radius using geochemical and geophysical data hinted at the absence of a lower mantle, but scientists needed InSight’s seismological readings to confirm it. Without this layer, the Martian core likely cooled much more readily than Earth’s. This is key to understanding the evolution of the Red Planet, and in particular why it lost its magnetic field, a barrier that would have protected the atmosphere—and potential life—from harsh solar winds. Creating a magnetic field requires a temperature gradient between the outer and inner core, high enough to create circulating currents that churn the core’s liquid and give rise to a magnetic field. But the core cooled so fast that these convection currents died out.

 

Khan’s analysis also shows that Mars has a thick lithosphere, the rigid and cold part of the mantle. This might be a clue as to why the Red Planet doesn’t have the plate tectonics that drive the frenzy of volcanism on Earth. “If you have a very thick lithosphere, it's going to be very difficult to break this thing up and create the exact equivalent of plate tectonics on Earth,” says Khan. “Maybe Mars had it very early on, but it's certainly shut down now.”

 

While InSight eavesdrops on the interior vibrations of Mars, Perseverance has been rolling around its dusty surface looking for signs of ancient life in the rocks, scoping out places to collect regolith samples, and learning about Jezero’s geological history. “Exploration is not a sprint, it’s a marathon,” said Thomas Zurbuchen, NASA’s associate administrator of science, who opened the press conference on Wednesday that highlighted early advances from the rover’s first few months in its new home. “Perseverance is one step in a long legacy of carefully planned Mars exploration that links robotic and human exploration for the time to come.”

 

The scientists at the press briefing laid out what Perseverance has been up to on its road trip so far. “The challenge is figuring out exactly where we want to go and how we’re going to fit everything into our schedule,” said Vivian Sun, a systems engineer at NASA’s Jet Propulsion Laboratory. Sun said they decided to detour Perseverance about 3,000 feet south of its landing site to extract its first rock samples, which will be stored in the belly of the rover and later cached on the planet’s surface for a future return mission that will ferry them to Earth.

 

Perseverance is equipped with a 7-foot arm carrying a suite of new gadgets, including the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE, that has already demonstrated the conversion of small amounts of atmospheric carbon dioxide into oxygen. The arm also includes sensors to assess the present climate and high-resolution cameras to take pictures of the rover's surroundings. “We’re getting photobombed by dust devils,” said Caltech geochemist Ken Farley, and large wind gusts that, to him, appear very Earth-like.

 

Some of the rocks in the images resemble hardened lake mud, which might indicate a good place to search for fossilized biosignatures—signs of former life. The team is also interested in figuring out whether the rocks in the crater are of sedimentary or volcanic origin; if the latter, they can be radiometrically dated to better understand the geologic timeline of the materials Perseverance is collecting. Farley says the most surprising observation they’ve made so far is evidence of flash flooding and varying water levels, suggesting that in the past the crater went through several phases of drying out and filling back up with liquid water.

 

With its newly designed AI-powered software, Perseverance also broke the record for the longest time a rover has ever driven itself on Mars—on only its second day of driving solo. “Autonomous driving is now just about as fast as human-directed driving,” said Olivier Toupet, a JPL roboticist. While humans can remotely steer Perseverance around 100 feet per day, carefully maneuvering it around obstacles, the AI software allows for increased agility. It creates a three-dimensional mapping of the surface while the rover is driving, so it can update and optimize its route in real time. Toupet said the longest autonomous Martian drive so far has been about 350 feet, and they expect Perseverance to quadruple that distance within the next few weeks.

 

After its southern detour, Perseverance will trek northwest to the site of an ancient river delta that once fed water into Jezero Crater. Then it will fully ramp up its use of instruments on the robotic arm to discover the elemental composition, mineralogy, shape, and texture of the nearby Martian rocks, information that will help scientists learn about the basin’s past water flow.

 

A few thousand miles away, InSight will continue to record quakes and reveal the inner workings of the first rocky planet, other than our own, that scientists have been able to characterize with seismology. “It’s a very young field for humanity,” Cottaar says. “We’ve been looking up at the stars much longer than we’ve been looking beneath our feet.”

Scientists Just ‘Looked’ Inside Mars. Here’s What They Found

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Event Horizon Telescope captures birth of black hole jet in Centaurus A

Images narrow down possible theoretical explanations for how black hole jets form.

 

The Event Horizon Telescope (EHT) collaboration made headlines in 2019 by capturing the very first direct image of a black hole at the center of a galaxy. Now, the EHT is back with another exciting breakthrough: images of the "dark heart" of a radio galaxy known as Centaurus A. The images enable the EHT to pinpoint the location of the supermassive black hole at the galaxy's center, according to a new paper published in the journal Nature Astronomy. The images also capture the birth of a powerful jet emitting from the black hole. The jet's unusual characteristics could help astronomers answer a few nagging questions about how such jets are produced in the first place.

 

"This allows us for the first time to see and study an extragalactic radio jet on scales smaller than the distance light travels in one day," said co-author Michael Janssen, an astronomer at Max Planck Institute for Radio Astronomy in Bonn and Radboud University Nijmegen. "We see up close and personally how a monstrously gigantic jet launched by a supermassive black hole is being born."

 

Centaurus A (aka NGC 5128) is one of the largest and brightest objects in the night sky, making it especially popular with amateur stargazers, although it's only visible from the Southern Hemisphere and low northern latitudes. Located in the constellation Centaurus, the galaxy was discovered in 1826 by James Dunlop. In 1847, John Herschel noted its peculiar shape—it looks elliptical when viewed from Earth, with a lane of dust superimposed across it.

 

In 1949, astronomers identified Centaurus A as the first known source of radio waves outside the Milky Way galaxy. That's because the galaxy boasts an active galactic nucleus, which produces powerful jets that emit light in both X-ray and radio wavelengths that span distances far greater than the size of the galaxy itself. Centaurus A has been studied extensively ever since in the radio, optical, X-ray, and gamma-ray regimes.

 

As Ars' John Timmer reported back in 2019, the EHT isn't a telescope in the traditional sense. Instead, it's a collection of telescopes scattered around the globe. The EHT is created by interferometry, which uses light captured at different locations to build an image with a resolution similar to that of a telescope the size of the most distant locations. Interferometry has been used for facilities like ALMA (the Atacama Large Millimeter/submillimeter Array), where telescopes can be spread across 16 km of desert.

 

In theory, there's no upper limit on the size of the array, but to determine which photons originated simultaneously at the source, you need very precise location and timing information on each of the sites. And you still have to gather sufficient photons to see anything at all. So atomic clocks were installed at many of the locations, and exact GPS measurements were built up over time. For the EHT, the large collecting area of ALMA, combined with choosing a wavelength where supermassive black holes are very bright, ensured sufficient photons. The net result is a telescope that can do the equivalent of reading the year stamped on a coin in Los Angeles from New York City—assuming the coin was glowing at radio wavelengths.

 

The EHT announced the first direct image ever taken of a black hole at the center of an elliptical galaxy in 2019, located in the constellation of Virgo some 55 million light-years away: Messier 87 (M87). This image would have been impossible a mere generation ago, and it was made possible by technological breakthroughs, innovative new algorithms, and (of course) connecting several of the world's best radio observatories. The image confirmed that the object at the center of M87 is indeed a black hole. Small wonder that Science magazine named the image its Breakthrough of the Year.

 

What was still lacking was insight into the process behind the powerful twin jets produced by M87. Most matter near the edge of a black hole—attracted by the black hole's strong gravitational pull—falls in, but some particles can escape and get blown out via those massive jets at nearly light speed. But astronomers don't yet agree about how those jets get accelerated to such high speeds. Perhaps the mechanism is an accretion disk that produces a magnetic field, funneling some of that matter into a jet. Or maybe the rotational energy of the black hole as it spins is the culprit. Or the mechanism could be a combination of both.

 

Earlier this year, we reported on another groundbreaking result from the EHT collaboration: a new image of M87, this time showing how it looks in polarized light. The ability to measure that polarization for the first time—a signature of magnetic fields at the black hole's edge—yielded fresh insight into how black holes gobble up matter and emit powerful jets from their cores. The observations suggested that the magnetic fields at the black hole's edge are strong enough to push back on the hot gas and help it resist gravity's pull. So only the gas that slips through the magnetic field can spiral inward to the event horizon. Theoretical models that don't incorporate this feature of a strongly magnetized gas don't match the EHT's observations and thus can be ruled out.

 

The new images of Centaurus A place even more constraints around the various competing theories, further narrowing the possibilities. According to this latest EHT data, the radio emissions form massive lobes emanating outward from Centaurus A. But only the outer edges of the jets emit radiation, perhaps due to the jets colliding with galactic gas, thus heating the edge. "Now we are able to rule out theoretical jet models that are unable to reproduce this edge-brightening," said co-author Matthias Kadler of the University of Würzburg in Germany. "It's a striking feature that will help us better understand jets produced by black holes."

 

The new Centaurus A observations are also of interest because the black hole at its center is medium-sized: 55 million times the mass of our Sun. That falls smack in the middle between M87 (6.5 billion solar masses) and the mass of the black hole at the center of our own Milky Way galaxy (about 4 million solar masses). The jets emitted by Centaurus A's black hole look pretty much the same as the EHT's images of M87, just on a smaller scale. In other words, the Centaurus A black hole doesn't seem to behave differently from its bigger or smaller siblings, adding further credence to physicists' notion that these exotic objects can be defined just by their mass, charge, and spin.

 

"These data are from the same observing campaign that delivered the famous image of the black hole in M87," said co-author Heino Falcke of Radboud University. "The new results show that the EHT provides a treasure trove of data on the rich variety of black holes, and there is still more to come." One day, the collaboration hopes to use space-based telescopes to capture a direct image of the black hole at the center of Centaurus A, just like they did for M87.

 

DOI: Nature Astronomy, 2021. 10.1038/s41550-021-01417-w  (About DOIs).

Event Horizon Telescope captures birth of black hole jet in Centaurus A

Although in-school transmission of COVID-19 among K-12 students is low when safeguards are in place, the risk of acquiring COVID-19 during school bus transportation is unclear. A study published in the Journal of School Health reports on the bus transport experience of an independent school in Virginia.

For the study, the school monitored 1,154 students with asymptomatic PCR testing every 2 weeks initially and later every week from August 28, 2020-March 19, 2021, during highest community transmission. Fifteen buses served 462 students while operating at near capacity of 2 students in every seat, using a physical distancing minimum of 2.5 feet, universal masking, and simple ventilation techniques.

There were 39 infectious COVID-19 cases who were present on buses during the study period, which resulted in the quarantine of 52 students. Universal testing and contact tracing revealed no transmission linked to bus transportation.

"The pandemic has made it very difficult for public schools to meet the transportation needs of students. Many districts simply do not have enough buses and drivers to allow distancing of 3-6 feet or skipping of bus rows while still providing rides to all children," said corresponding author Dana Ramirez, MD, of Children's Hospital of the King's Daughters. "With more students returning to face-to-face instruction, safe transportation to school is an equity issue, as many families are unable to drive their children to school each day. As members of the Virginia Chapter of the American Academy of Pediatrics School Re-Opening Task Force, we recognize that schools are under pressure to make data-driven operational decisions. We hope the model we describe and our data can be of assistance in demonstrating that school buses can safely operate at normal capacity even at high community COVID-19 case loads."

Source

The finding comes out of an effort to map where vegetation is emitting and soaking up carbon dioxide from the atmosphere.

Earth's trees and plants pull vast amounts of carbon dioxide out of the atmosphere during photosynthesis, incorporating some of that carbon into structures like wood. Areas that absorb more carbon than they emit are called carbon sinks. But plants can also emit the greenhouse gas during processes like respiration, when dead plants decay, or during combustion in the case of fires. Researchers are particularly interested in whether—and how—plants at the scale of an ecosystem like a forest act as sources or sinks in an increasingly warming world.

A recent study led by scientists at NASA's Jet Propulsion Laboratory in Southern California identified whether vegetated areas like forests and savannas around the world were carbon sources or sinks every year from 2000 to 2019. The research found that over the course of those two decades, living woody plants were responsible for more than 80% of the sources and sinks on land, with soil, leaf litter, and decaying organic matter making up the rest. But they also saw that vegetation retained a far smaller fraction of the carbon than the scientists originally thought.

In addition, the researchers found that the total amount of carbon emitted and absorbed in the tropics was four times larger than in temperate regions and boreal areas (the northernmost forests) combined, but that the ability of tropical forests to absorb massive amounts of carbon has waned in recent years. The decline in this ability is because of large-scale deforestation, habitat degradation, and climate change effects, like more frequent droughts and fires. In fact, the study, published in Science Advances, showed that 90% of the carbon that forests around the world absorb from the atmosphere is offset by the amount of carbon released by such disturbances as deforestation and droughts.

The scientists created maps of carbon sources and sinks from land-use changes like deforestation, habitat degradation, and forest planting, as well as forest growth. They did so by analyzing data on global vegetation collected from space using instruments such as NASA's Geoscience Laser Altimeter System (GLAS) on board ICESat and the agency's Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra and Aqua satellites, respectively. The analysis used a machine-learning algorithm that the researchers first trained using vegetation data gathered on the ground and in the air using laser-scanning instruments.

Taking Stock

"A lot of research that has come before hasn't been spatially explicit—we haven't had a map of where carbon fluxes were occurring," said Nancy Harris, research director of the forest program at the World Resources Institute in Washington and one of the study authors.

This map shows the change in how much carbon a vegetated area stored or emitted between the years 2000 and 2019. Greener areas absorbed more carbon than they emitted, while more pink and purple regions released more carbon than they stored. One megagram of carbon (MgC) is one metric ton. Credit: NASA/JPL-Caltech

Other ways of estimating how much carbon is exchanged between vegetated areas and the atmosphere include looking at how many plants or forests are in a particular region and studying land-use changes, combining that information with carbon emission estimates. But those methods have spatial or temporal limitations that the study authors tried to address with their machine-learning method.

Knowing where plants are taking up carbon and where they're emitting it is important for monitoring how forests and other vegetated regions respond to a changing climate. "The Amazon was considered a substantial carbon sink because of large tracts of pristine forest that soak up carbon dioxide," said Sassan Saatchi, principal scientist at JPL and the study lead investigator. "However, our results show that overall, the Amazon Basin is becoming almost neutral in terms of carbon balance because deforestation, degradation, and the impacts of warming, frequent droughts, and fires over the past two decades release carbon dioxide to the atmosphere."

Saatchi and his colleagues developed their analysis so that it's easier to track changes in vegetated areas based on data collected on the ground as well as remotely. "Our approach is designed to make sure we can systematically balance the global carbon budget every year, and that countries can use the results and methodology for carbon management and their own reporting needs," he said.

This budgeting analysis helped the researchers better understand the dynamics of how forests and other vegetated areas around the world were storing the carbon that they're absorbing from the atmosphere. "Many previous studies found that vegetation around the world absorbs a lot of atmospheric carbon dioxide," said study lead author Alan Xu, a carbon researcher at JPL and UCLA. "It gives the impression that global forests are growing and getting bigger everywhere, but that's not the case."

Missing Pieces

This study helps to fill in the picture of where and how trees and plants are absorbing or emitting carbon, but there's more work to be done. The satellite-based carbon maps in this study covered about 39 square miles (100 square kilometers) at a time, but they couldn't necessarily pick up changes happening on smaller scales. And there was some information about how forests stored and emitted carbon within those maps that wasn't necessarily accounted for in the researchers' source-sink calculations. Some of these information gaps should be remedied by higher-resolution carbon maps provided by newer satellites already in orbit, as well as upcoming missions like the NASA-Indian Space Research Organization's NISAR.

It's important to understand how regions around the world absorb and emit carbon dioxide, said Harris. "If we're not getting these patterns right, we may be missing some of these ecosystems and how they're affecting the carbon cycle." But she is encouraged by the sheer amount of data becoming available to climate scientists on how the greenhouse gas moves between the atmosphere and Earth's forests, grasslands, and other vegetated areas.

Saatchi is hopeful that having a more systematic and consistent approach to keeping track of which parts of the world are acting as carbon sources or sinks will enable better monitoring across regions and countries. "It could allow countries around the world to use the data as guidance for meeting their national commitments to the Paris Climate Agreement."

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One of the biggest myths about EVs is busted in new study

Blue Origin successfully completes its first human launch [Updated]

Blue Origin plans to fly two more customer flights in 2021.

 

9:45am ET Update: At 8:12 am local time in West Texas, about one hour after sunrise, Blue Origin's New Shepard launch system rocketed into the sky. The mission carried an eclectic mix of passengers—billionaire Jeff Bezos and his brother Mark, famed female aviator Wally Funk, and 18-year-old Oliver Daemen.

 

All four emerged from the capsule, in the west Texas desert, less than 20 minutes later. During the flight they reached an altitude of 107 km, crossing the internationally agreed upon boundary of space.

 

This was Blue Origin's first human spaceflight and follows Virgin Galactic's successful flight of its founder, Sir Richard Branson, nine days ago. We truly have entered into a new era of human spaceflight.

 

Original post: Officials with the rocket company Blue Origin said they remain on track for their first human spaceflight on Tuesday, which will carry founder Jeff Bezos and three other passengers on a suborbital hop 100 km above West Texas.

 

Steve Lanias, the lead flight director for the mission, said during a call with reporters that engineers completed a "Flight Readiness Review" for the launch over the weekend and found the New Shepard rocket and capsule to be in perfect condition. Weather, too, looks reasonable with any early morning storms expected to pass before the anticipated liftoff time of 8 am CT (13:00 UTC).

 

Bezos and the other three passengers—his brother, Mark, aviation pioneer Wally Funk, and a paying customer from the Netherlands named Oliver Daemen—underwent about 14 hours of training this weekend across two days. Their flight will be entirely autonomous. After launch the capsule will separate from the rocket, and the passengers will have about three minutes of weightlessness before they must strap back into their seats for the return to Earth. Upon reentry to Earth's atmosphere the passengers will experience about 5 Gs as gravity exerts itself on the returning vehicle.

 

This particular capsule and rocket has made two flights previously, said Blue Origin CEO Bob Smith. Although Blue Origin has a handful of former astronauts on staff, the company decided to fly its first flight with Bezos, his invited guests, and a customer rather than having the former astronauts test the vehicle. "We didn’t see any value, quite honestly, in doing things stepwise in that approach," Smith said.

 

An unnamed bidder paid $28 million at an auction for a seat on this flight but then backed out due to scheduling conflicts, Blue Origin said. The company then turned to a runner-up during the auction, Dutch hedge fund manager Joes Daemen. He paid an unspecified price for the seat to fly his son, Oliver.

 

Smith said 7,500 people from 150 countries participated in Blue Origin's auction for the New Shepard seat. The company has not disclosed how much it will charge for seats on New Shepard, but Blue Origin seems intent on getting whatever price the market will bear, with seats on early flights expected to cost significantly more than $1 million. "The early flights are going for a good price," Smith said.

 

Blue Origin plans to fly two more customer flights in 2021, and although the company did not say, it is likely to fly about a dozen such missions in 2022 as long as there are no significant technical problems.

 

For Tuesday's flight, the company will provide a webcast, which is expected to begin about 90 minutes before the anticipated liftoff time. So the webcast should go live at 6:30 am local time in Texas, or about 11:30 UTC.

 

Blue Origin successfully completes its first human launch [Updated]

Adelaide will on Tuesday become the latest in a string of Australian cities to lock down, as the largely unvaccinated nation struggles to contain a rapidly spreading coronavirus outbreak.

The state of South Australia, of which Adelaide is the capital, said it would join Sydney and Melbourne in locking down after five local cases were detected.

The decision means more than 14 million Australians are now under orders to stay at home.

"From 6pm tonight, South Australia moves into lockdown," state premier Steven Marshall said from Adelaide, indicating the measures would be in place for at least seven days.

"We hate putting these restrictions in place, but we believe we have just one chance—one chance to get this right."

Only 11 percent of Australia's 25 million people are currently vaccinated. But until now, widespread community transmission had been contained.

For the past month, authorities have been fighting to quash an outbreak of the fast-spreading Delta variant, which started after an overseas flight crew infected a Sydney driver.

The virus has since jumped state borders, creating around 100 new cases every day across the vast island nation.

A Sydney lockdown, now in its fourth week, has slowed the spread of the virus there but has failed to eliminate new infections.

The Sydney outbreak has now grown to 1,418 cases, with 78 new infections reported on Tuesday.

Residents are only allowed to leave home for exercise, to buy food or for a handful of other closely defined reasons.

At the same time, authorities in Melbourne on Tuesday said a snap five-day lockdown, which had been due to end, would be extended at least another seven days.

In Queensland, authorities are also on high alert after a woman who visited several tourist sites tested positive for the virus.

Source

Sip a venti dark roast and eat a salad. A new Northwestern Medicine study shows coffee consumption and eating lots of vegetables may offer some protection against COVID-19.

The authors believe this is the first study using population data to examine the role of specific dietary intake in prevention of COVID-19.

"A person's nutrition impacts immunity," said senior author Marilyn Cornelis, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. "And the immune system plays a key role in an individual's susceptibility and response to infectious diseases, including COVID-19."

Being breastfed may also offer protection as well as eating less processed meats, the study found.

"Besides following guidelines currently in place to slow the spread of the virus, we provide support for other relatively simple ways in which individuals can reduce their risk and that is through diet and nutrition," Cornelis said.

The paper on nutrition and COVID-19 protection was published recently in the journal Nutrients.

One or more cups of coffee per day was associated with about a 10% decrease in risk of COVID-19 compared to less than one cup per day. Consumption of at least 0.67 servings per day of vegetables (cooked or raw, excluding potatoes) was associated with a lower risk of COVID-19 infection. Processed meat consumption of as little as 0.43 servings per day was associated with a higher risk of COVID-19. Having been breastfed as a baby reduced the risk 10% compared to not having been breastfed.

While the study shows diet appears to modestly reduce disease risk, the Centers for Disease Control and Prevention recommends vaccines as the most effective way to prevent COVID-19 disease, especially severe illness and death. COVID-19 vaccines also reduce the risk of people spreading the virus that causes COVID-19.

Thus far, most COVID-19 research has focused on individual factors assessed after a positive COVID-19 test. Individuals with suppressed immune systems such as the elderly and those with existing comorbidities including cardiovascular diseases, hypertension, diabetes and obesity, are more likely to experience severe outcomes of COVID-19.

But other than weight management, less attention has focused on other modifiable risk factors preceding COVID-19 infection, said Cornelis, who studies how diet and nutrition contribute to chronic disease.

Dr. Thanh-Huyen Vu, the study's first author and a research associate professor of medicine at Northwestern, is now leading analyses to determine whether these protective diet behaviors are specific to COVID or respiratory infections more broadly.

Exact mechanisms linking these diet factors to COVID are unknown.

"Coffee is a major source of caffeine, but there are also dozens of other compounds that may potentially underlie the protective associations we observed," Cornelius said. "Associations with processed meat, but not red meat, point to non-meat factors."

Using data from the UK Biobank, researchers examined the associations between dietary behaviors measured in 2006-2010 and COVID-19 infections in March to December 2020, before vaccines were available. They focused on 1) diet factors for which data were available and previously implicated in immunity based on human and animal studies; 2) self-reported intakes of coffee, tea, vegetables, fruit, fatty fish, processed meat and red meat. An early-life exposure to breastmilk also was analyzed.

Among the 37,988 participants tested for COVID-19 and included in the study, 17% tested positive.

The observational nature of the UK Biobank research limits the extent to which mechanisms of protection can be tested, Cornelis said. However, much of her nutrition research uses genetics, and with all UK Biobank participants currently genotyped, she hopes to use this information to gain better insight into how diet and nutrition offer protection from the disease.

Source

The second dose of a COVID-19 vaccine induces a powerful boost to a part of the immune system that provides broad antiviral protection, according to a study led by investigators at the Stanford University School of Medicine.

The finding strongly supports the view that the second shot should not be skipped.

"Despite their outstanding efficacy, little is known about how exactly RNA vaccines work," said Bali Pulendran, Ph.D., professor of pathology and of microbiology and immunology. "So we probed the immune response induced by one of them in exquisite detail."

The study, published July 12 in Nature, was designed to find out exactly what effects the vaccine, marketed by Pfizer Inc., has on the numerous components of the immune response.

The researchers analyzed blood samples from individuals inoculated with the vaccine. They counted antibodies, measured levels of immune-signaling proteins and characterized the expression of every single gene in the genome of 242,479 separate immune cells' type and status.

"The world's attention has recently been fixed on COVID-19 vaccines, particularly on the new RNA vaccines," said Pulendran, the Violetta L. Horton Professor II.

He shares senior authorship of the study with Kari Nadeau, MD, Ph.D., the Naddisy Foundation Professor of Pediatric Food, Allergy, Immunology, and Asthma and professor of pediatrics, and Purvesh Khatri, Ph.D., associate professor of biomedical informatics and of biomedical data science. The study's lead authors are Prabhu Arunachalam, Ph.D., a senior research scientist in Pulendran's lab; medical student Madeleine Scott, Ph.D., a former graduate student in Khatri's lab; and Thomas Hagan, Ph.D., a former postdoctoral scholar in Pulendran's Stanford lab and now an assistant professor at the Yerkes National Primate Research Center in Atlanta.

Uncharted territory

"This is the first time RNA vaccines have ever been given to humans, and we have no clue as to how they do what they do: offer 95% protection against COVID-19," said Pulendran.

Traditionally, the chief immunological basis for approval of new vaccines has been their ability to induce neutralizing antibodies: individualized proteins, created by immune cells called B cells, that can tack themselves to a virus and block it from infecting cells.

"Antibodies are easy to measure," Pulendran said. "But the immune system is much more complicated than that. Antibodies alone don't come close to fully reflecting its complexity and potential range of protection."

Pulendran and his colleagues assessed goings-on among all the immune cell types influenced by the vaccine: their numbers, their activation levels, the genes they express and the proteins and metabolites they manufacture and secrete upon inoculation.

One key immune-system component examined by Pulendran and his colleagues was T cells: search-and-destroy immune cells that don't attach themselves to viral particles as antibodies do but rather probe the body's tissues for cells bearing telltale signs of viral infections. On finding them, they tear those cells up.

In addition, the innate immune system, an assortment of first-responder cells, is now understood to be of immense importance. It's the body's sixth sense, Pulendran said, whose constituent cells are the first to become aware of a pathogen's presence. Although they're not good at distinguishing among separate pathogens, they secrete "starting gun" signaling proteins that launch the response of the adaptive immune system—the B and T cells that attack specific viral or bacterial species or strains. During the week or so it takes for the adaptive immune system to rev up, innate immune cells perform the mission-critical task of holding incipient infections at bay by gobbling up—or firing noxious substances, albeit somewhat indiscriminately, at—whatever looks like a pathogen to them.

A different type of vaccine

The Pfizer vaccine, like the one made by Moderna Inc., works quite differently from the classic vaccines composed of live or dead pathogens, individual proteins or carbohydrates that train the immune system to zero in on a particular microbe and wipe it out. The Pfizer and Moderna vaccines instead contain genetic recipes for manufacturing the spike protein that SARS-CoV-2, the virus that causes COVID-19, uses to latch on to cells it infects.

In December 2020, Stanford Medicine began inoculating people with the Pfizer vaccine. This spurred Pulendran's desire to assemble a complete report card on the immune response to it.

The team selected 56 healthy volunteers and drew blood samples from them at multiple time points preceding and following the first and second shots. The researchers found that the first shot increases SARS-CoV-2-specific antibody levels, as expected, but not nearly as much as the second shot does. The second shot also does things the first shot doesn't do, or barely does.

"The second shot has powerful beneficial effects that far exceed those of the first shot," Pulendran said. "It stimulated a manifold increase in antibody levels, a terrific T-cell response that was absent after the first shot alone, and a strikingly enhanced innate immune response."

Unexpectedly, Pulendran said, the vaccine—particularly the second dose—caused the massive mobilization of a newly discovered group of first-responder cells that are normally scarce and quiescent.

First identified in a recent vaccine study led by Pulendran, these cells—a small subset of generally abundant cells called monocytes that express high levels of antiviral genes—barely budge in response to an actual COVID-19 infection. But the Pfizer vaccine induced them.

This special group of monocytes, which are part of the innate museum, constituted only 0.01% of all circulating blood cells prior to vaccination. But after the second Pfizer-vaccine shot, their numbers expanded 100-fold to account for a full 1% of all blood cells. In addition, their disposition became less inflammatory but more intensely antiviral. They seem uniquely capable of providing broad protection against diverse viral infections, Pulendran said.

"The extraordinary increase in the frequency of these cells, just a day following booster immunization, is surprising," Pulendran said.

"It's possible that these cells may be able to mount a holding action against not only SARS-CoV-2 but against other viruses as well."

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For decades, doctors have warned folks suffering from heart rhythm problems to avoid coffee, out of concern that a caffeine jolt might prompt a herky-jerky heartbeat.

But a large new study has found that most people can enjoy their morning joe or afternoon diet cola free from worry—caffeine doesn't seem to increase most people's risk of arrhythmias.

"We see no evidence for this broad-based recommendation to avoid coffee or caffeine," said study co-author Dr. Gregory Marcus, associate chief of cardiology for research at the University of California, San Francisco. "There could be some individuals where caffeine is their trigger, but I think the growing evidence is those cases are actually quite rare."

In fact, results indicate that every additional cup of coffee a person drinks daily might lower their risk of arrhythmia by about 3% on average, according to the study published July 19 in JAMA Internal Medicine.

"The majority of people, even those with arrhythmias, should be able to enjoy their cup of coffee, and maybe there are some people for whom caffeine or coffee may actually help reduce their risk," Marcus said.

Coffee is one of the most widely consumed beverages worldwide, but its properties as a stimulant have prompted many doctors to warn heart patients against drinking java, Marcus said.

To see whether caffeine really can cause the heart to race or beat abnormally, Marcus and his colleagues analyzed data from more than 386,000 people participating in a long-term British health study.

Of that large group, about 17,000 developed a heart rhythm problem during an average follow-up of 4.5 years, researchers said.

All participants were asked about their coffee consumption when they entered the study. Researchers compared their response to their likelihood of developing an abnormal heart rhythm down the line.

The result: There was no link at all between caffeine and heart rhythm disturbances, even when researchers took into account genetic factors that might influence the way individuals metabolize caffeine.

"We could find no evidence on a population level that those who consumed more coffee or those exposed to more caffeine experienced a heightened risk for arrhythmias," Marcus said.

The study results show "there is absolutely some unsubstantiated dogma that coffee can cause arrhythmias," said Dr. Zachary Goldberger, an associate professor of cardiovascular medicine at the University of Wisconsin-Madison.

However, Goldberger cautioned against reading too much into what the study observed about caffeine's potential protective benefits, given that the effect was so small.

"I think the bottom line, based on these findings, is that coffee may not cause arrhythmias, but it doesn't necessarily protect against them either," said Goldberger, co-author of a commentary accompanying the study.

Further research is needed to suss out exactly how coffee affects the heart, and why it might protect against arrhythmias, Marcus said.

Coffee has anti-inflammatory effects, and it's well-known that inflammation can contribute to heart rhythm problems, Marcus said. It also might be that caffeine motivates some people to be more physically active, which reduces the risk of arrhythmia.

"We are probably not fully aware of the various mechanisms that may be relevant" to the relationship between caffeine and heart health, Marcus said.

Marcus said that he encourages his own heart rhythm patients to experiment with coffee.

"In many cases anecdotally, it doesn't make a difference," Marcus said. "For most, I have not found that it's an important trigger. They are very happy to receive this good news, especially those who enjoy coffee."

Both Marcus and Goldberger acknowledge there are probably some individuals who don't respond well to coffee, and their concerns should continue to be taken seriously.

"If a patient comes to clinic with palpitations, or symptoms of an arrhythmia, and asks whether caffeine or coffee plays a role, that is a personalized discussion," Goldberger said. "If a patient reports having palpitations that seem correlated with coffee or caffeinated beverages, these data don't give us the license to tell them not to try to limit coffee. But I think we could tell our patient that coffee doesn't place people at higher risk of heart rhythm disturbances."

Source

Genealogists say Leonardo da Vinci has 14 living relatives

The Renaissance artist and scientist's youngest living relative is 1 year old.

A recently assembled Leonardo da Vinci family tree, spanning 21 generations from 1331 to the present, could pave the way for DNA testing that might confirm whether the bones interred in da Vinci’s grave are actually his. Two art historians’ hopes of uncovering a genetic explanation for the Renaissance artist’s brilliance, however, will probably be doomed by scientific reality.

Da Vinci’s modern family

To construct the family tree, art historians Alessandro Vezzosi and Agnese Sabato dug through birth, death, and property records spanning the last 690 years. They also interviewed surviving relatives to learn more about the famous artist, scientist, and inventor’s modern extended family. In the end, they traced da Vinci’s family from his grandfather, born in 1331, to the 14 relatives living today. Leonardo da Vinci himself had no children, and his modern relatives all descend from his 22 (!) half-siblings.

 

The present family played an essential role in the new study. “Many of them have collaborated, together with their relatives, to the collection and verification of information,” wrote Vezzosi and Sabato, “helping enthusiastically to contact other family members and retrieve new documents and images.” Those many-times-great nieces and nephews include several office workers (one of whom served as a naval gunner in the 1960s), a retired upholsterer, a surveyor, and a state employee who is “passionate about motorcycling and music.” The oldest is now 85 years old, and the youngest is just one year old.

 

For some interesting historical perspective, the artist’s grandfather, Michele da Vinci, would have been a teenager when the Black Death arrived in Italy; his latest 20-times-great niece or nephew was born during the Covid-19 pandemic.

Who is buried in da Vinci’s grave?

Vezzosi and Sabato were especially interested in the male line of descent from da Vinci’s father, a notary named Ser Piero da Vinci, to today’s generations. That’s partly because the male line is easier to trace in historical documents from a time where women’s lives—and sometimes their whole existence—seldom got written down in official records. But it’s mostly because of the Y chromosome, the only part of the human genome that gets passed down directly from father to son. Aside from some small changes that happen over time, the Y-chromosomes of da Vinci’s modern nephews should be extremely similar to those of Michele, Ser Piero, and Leonardo himself.

 

That means that by comparing the Y chromosome DNA of modern relatives to ancient DNA from the skeleton buried in da Vinci’s grave, it may be possible to solve a 158-year-old mystery: who is buried in da Vinci’s grave in the Chapel of Saint-Hubert?

 

Leonardo da Vinci spent the last four years of his life in France, working as a scientist and engineer in the court of King Francis I. He lived and worked in the town of Amboise, a stone’s throw from the king’s summer palace, and when he died in 1519, he was buried in the nearby church of St. Florentine, about 1,200 km (750 miles) from the rest of his family. (By all accounts, Leonardo had little contact with his half-brothers; several were more than a decade younger, and historical documents suggest some conflicts over inheritance.)

 

And there the great Renaissance scholar lay for the next 275 years or so, until revolution came to his adopted country. During the French Revolution, the church of St. Florentine was mostly demolished; Napoleon Bonaparte finished the job a few years later. In the process, da Vinci’s tomb, and his bones, disappeared.

 

Workers at the site found a skeleton in 1863, buried along with some fragments of stone carved with letters: “EO,” “AR,” “DUS,” and “VINC,” which the finders read as broken pieces of an inscription that once said “Leonardus da Vinci.” The skeleton’s teeth looked worn enough to fit da Vinci’s age when he died, and a silver shield etched with an image of King Francis I suggested the right time period. Today, the skeleton resides in a tomb at the nearby Chapel of Saint-Hubert, but DNA testing could help confirm whether it’s really Leonardo.

 

Of course, such testing would require permission—possibly from the church, from surviving relatives, from cultural heritage officials, or some combination of those. It’s unclear whether anyone would be keen on destructive sampling from what is widely believed to be the skeleton of Leonardo da Vinci. However, it’s interesting that ownership of the skeleton is a testable hypothesis now, even if only technically.

Da Vinci’s missing family

Most of Leonardo’s late medieval and Renaissance-era family members were buried in the church of Santa Croce in Vinci, a town about 20 miles from Florence, Italy, from which the family gets its name. Later generations changed the family name from "da Vinci" to just "Vinci." But the family tomb, in which at least six of the artist’s male relatives are buried, has been lost to time and several renovations of the church building. That means the bodies of Leonardo’s grandfather Antonio, his uncle Francesco, and his half-brother Domenico di Matteo, among others, are technically missing, although they're almost certainly still somewhere under the modern church floor.

 

Vezzosi and Sabato and their colleagues at the International Leonardo da Vinci DNA Project are interested in finding those graves because they hope to sample DNA from several generations of da Vinci’s male family line. That, they claim, would help confirm that the family tree recorded in nearly 700 years of documents matches the actual genetic relationships between people.

 

A recent ground-penetrating radar survey looked for traces of forgotten tombs under the church floor. Historical records say the old da Vinci tomb lay near the center of the building, opposite its main door; by comparing historical floor plans to modern ones, Vezzosi and Sabato managed to find the area of the church that would once have been the center, opposite the main door. And in about the right spot, their radar survey detected two anomalies—places where the radio waves reflect differently than in the surrounding soil.

 

It’s unlikely that church officials would grant permission to dig up the floor in front of the altar to look for Leonardo da Vinci’s relatives. Exhuming several sets of remains to get DNA samples would likely require significant resources and raise serious ethical concerns. Researchers typically have to show that they’re asking very compelling scientific questions in order to get permission and funding to undertake that kind of project, and ground-truthing a historical figure’s family tree probably falls short of the standard.

No such thing as a Da Vinci Code

Many of Vezzosi and Sabato's plans for da Vinci’s DNA—if it’s ever sequenced—don’t actually make scientific sense. They’re largely based on some outdated ideas about heredity, intelligence, and even race.

 

Sequencing Leonardo da Vinci's DNA, Vezzosi and Sabato wrote, “will make available useful elements to scientifically explore the roots of his genius, to find information on his physical prowess and on his possibly precocious aging, on his being left-handed and his health and possible hereditary sicknesses, and to explain certain peculiar sensory perceptions, like his extraordinary visual quality and synesthesia.”

 

A few specific traits, like left-handedness and some hereditary health problems, might be at least partially written in da Vinci’s genes. Others, like synesthesia, may have a genetic basis since it tends to run in families, but geneticists haven’t yet pinpointed one. But there’s no known genetic marker for intelligence or creativity. The deeply harmful eugenics movement of the early 20^th century was based on the idea that intelligence and morality were traits that people simply inherited from their parents, an idea that persists today.  But science tells a very different story, with environmental influences mixing with the input of hundreds of genes, each having a tiny effect.

 

“We further deem significant and fascinating the hypothesis that Leonardo was born from a genetic interaction of two different haplotypes, that is, from the characteristics of two different populations,” Vezzosi and Sabato wrote. Some historians have suggested that da Vinci’s mother Caterina may have been an enslaved woman from Caffa or Constantinople, but Vezzosi and Sabato speculate by asking, “Could this be the origin of Leonardo’s genius?”

 

The idea sounds like something out of the 19^th century.

 

All in all, the idea of studying Leonardo’s DNA to learn what made him tick offers a great example of why researchers shouldn’t just blindly charge off to work outside their own fields. Multidisciplinary research is important, but it works best when experts in different fields work together.

 

Human Evolution, 2021 DOI: 10.14673/HE2021121077  (About DOIs).

Genealogists say Leonardo da Vinci has 14 living relatives