"It takes only small-to-moderate amounts of vitamin D to have optimal cardiovascular function," said JoAnn E. Manson M.D., Dr.P.H., a study author and chief of the division of preventive medicine at Brigham and Women's Hospital and Harvard Medical School. "More is not better," she explained.

Through ongoing research, Manson has found that adults who take either moderate or high-dose daily vitamin D supplements of at least 1,000 IU haven't had a reduced risk for having a heart attack, stroke, or cardiovascular-related death compared to adults taking a placebo without vitamin D.

This research, which has been supported by the Vitamin D and Omega-3 Trial (VITAL), aligns with recommendations released in June by the U.S. Preventive Services Task Force, which cited insufficient evidence to recommend adults take vitamin D or any other supplement to prevent cardiovascular disease.

These findings also add to mounting evidence that vitamin D supplements are not the panacea many thought they were for a host of health problems.

VITAL and other randomized trials have found, for example, that higher intakes haven't prevented cancer, bone fractures, or falls, nor have they alleviated knee pain, cognitive decline, or atrial fibrillation—among other conditions.

It is why researchers have begun shifting their focus to other more nuanced questions about the vitamin. For example, why do some people benefit from it more than others? Could supplements benefit specific populations, such as those with increased risks for heart disease? And given that VITAL showed high-dose vitamin D supplements reduced risks for autoimmune conditions, could they also help reduce the severity of COVID-19?

Vitamin D Get enough, but not too much

While researchers sort through these questions, the guidelines that have been in place for years still apply.

The National Academy of Medicine recommends a daily intake of 600 IU of vitamin D (mostly from foods) for people ages 1–70 and 800 IU for adults ages 71 and older. However, Manson notes it is reasonable for adults concerned about not getting enough vitamin D to take a daily supplement of 1,000–2,000 IU during the pandemic. She cautions against taking more. Consuming more than 4,000 IU daily, the upper daily limit, is considered mega-dosing and could lead to adverse effects, including high calcium levels in the blood or kidney stones.

So what's the best way to get vitamin D?

Getting incidental sun exposure, such as by being physically active outdoors, and eating vitamin D-rich foods, including fatty fish, fortified dairy products and cereals, and certain mushrooms, such as those exposed to ultraviolet light, are good places to start, Manson explained. Reading nutrition labels can also help people assess how much vitamin D they consume through food.

After that, supplements can provide a boost for people concerned about getting too little. Or directly exposing the skin to sunlight for 15 minutes a few times each week will get you there, too, Manson said.

But when it comes to vitamin D and the prevention of heart disease, Manson said "all you need is to get into that middle range where you're not deficient."

Understanding vitamin D and heart health

The idea that higher vitamin D intake could improve heart health emerged years ago when observational studies found people with higher blood levels of vitamin D had lower rates of cardiovascular disease.

To see if vitamin D drove this effect or was just a marker of risk, researchers conducted randomized, controlled trials, including VITAL. In 2011–2013, more than 25,000 adults enrolled in VITAL, which found that high-dose vitamin D supplements did not prevent cardiovascular events. And Manson, a study director for VITAL, also conducted a meta-analysis about this topic. After reviewing 21 randomized trials related to vitamin D and cardiovascular disease, she found that "not a single one showed clear benefits of vitamin D supplements in preventing heart disease or stroke."

"In observational research, correlation does not prove causation," she explained, underscoring the need for randomized, controlled trials.

Multiple factors could explain why adults with higher vitamin D levels have been less likely to have cardiovascular disease in observational studies,

Manson said. Exercise is one. People who spend more time outdoors engaged in physical activity, which supports heart and vascular health, may have higher vitamin D levels from incidental sun exposure. Diet is another. Fish and other nutrient-dense meals support heart health and tend to be higher in vitamin D.

Inflammation is a third, she said. Levels of inflammation can serve as signals of disease. And since vitamin D can bind to a protein that's more likely to be depleted from inflammation, lower levels may be a marker, as opposed to a causal factor, for chronic conditions like heart disease.

However, once adults have sufficient vitamin D levels, the benefits plateau, Manson explained. "You don't have further cardiovascular disease risk reductions with higher intake or blood levels of vitamin D."

The future of vitamin D research

Researchers, including those leading VITAL, are now turning their attention to how vitamin D supplements may help people in other ways.

Some are looking at how high-dose vitamin D supplements may support immune function in people with autoimmune conditions, including rheumatoid arthritis, lupus, and psoriasis. In this case, the results appear promising. Adults who took a high-dose vitamin D supplement for five years had a 22% reduced risk for having an autoimmune condition. Other researchers, including Manson, are studying if vitamin D can reduce the severity of COVID-19 infections, shorten recovery, and lower the risk of long COVID.

Looking at how vitamin D may help people living with type 2 diabetes and cancer are the anchors of other studies. While vitamin D supplementation hasn't prevented cancer, Manson and other VITAL researchers are studying if higher intake may slow its progression and reduce cancer-related deaths.

Alvin A. Chandra, M.D., a VITAL researcher and assistant professor in the division of cardiology at the University of Texas Southwestern Medical Center, is also curious if a parallel relationship exists with vitamin D and heart disease.

"There may be subgroups of patients who are at higher risk for adverse cardiovascular outcomes who may benefit from vitamin D supplementation," he said. This could include people who have had a heart attack, stroke, or heart failure. And if there are benefits, either for vitamin D and/or omega-3 supplements, Chandra said he wants to know what levels would provide a protective effect.

VITAL researchers are also studying mechanisms that may influence or indicate how easily vitamin D can be absorbed and used by the body. These variables may help explain why about one in every four to five Americans is at risk for having inadequate levels of vitamin D.

Darker skin color can affect skin synthesis of vitamin D from sun exposure, for instance. According to the 2011–2014 National Health and Nutrition Examination Survey, about one in six Black children or adults was at risk for having a vitamin D deficiency compared to one in 13 Asian Americans, one in 17 Hispanics, and one in 40 whites. Aging, allergies, and underlying conditions, including Crohn's disease and celiac disease, can also impair absorption and have other effects, as can limited sun exposure, dietary restrictions, and extended breastfeeding.

How vitamin D interacts with other nutrients, such as magnesium and vitamin K, and impacts its absorption and biological actions are topics of other studies, Manson added. Researchers are also studying genetic links that may explain differences in how the vitamin is metabolized and binds to receptors.

The result, she explained, could lead to personalized vitamin D requirements. Particular groups that benefit most from supplementation could also be identified and helped.

"This is all part of precision prevention," she explained.

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The study also showed the benefits linked to devolution on life expectancy were felt in the most deprived local authorities where there was poorer health, suggesting a narrowing of inequality.

The study, published in The Lancet Public Health, showed that between 2014/16 and 2017/19:

•     Life expectancy was 0.2 years higher in Greater Manchester compared to a comparable control group from the rest of England. The change in Greater Manchester was 2.2 times larger than the average change in life expectancy over the same period.

•     The change persisted throughout the period after the devolution deal and was larger for men (0.34 years) than for women (0.06 years).

•     Statistically significant increases in life expectancy were observed in eight out of the ten local authorities in Greater Manchester, with the exceptions of Rochdale (decrease) and Oldham (no change).

•     In the short-term, life expectancy remained constant in Greater Manchester but declined in comparable areas in England. In the longer-term, life expectancy increased at a faster rate in Greater Manchester than in the rest of the country.

•     Improvements in life expectancy were larger in the local authorities with the worst levels of income deprivation and lowest life expectancy prior to devolution, when compared to areas with equally high deprivation and low life expectancy in the rest of England.

The improvements, say the researchers, may have been a result of a combination of changes in response to the devolution deals in the region, including the health and social care devolution agreement, the devolution of powers over wider determinants of health (such as housing, employment, transport, adult education, policing, and economic development), and the election of a Greater Manchester mayor.

The study, which is the first of first kind, estimated the impact of devolution on the population stratified by sex, local authority, income deprivation, and life expectancy compared to the rest of England, excluding London.

The researchers used local authority data on life expectancy at birth published by the Office for National Statistics between 2006 and 2019 to calculate the relationship.

Lead author Dr. Philip Britteon Research Fellow at The University of Manchester said, "We provide the first robust evidence on the impact of devolution in England on population health, focusing on changes occurring in Greater Manchester.

"The study shows modest improvements in life expectancy in Greater Manchester compared to comparable areas in the rest of the country from the introduction of devolution until the start of the COVID-19 pandemic in 2020, using a robust statistical method.

"This finding may have been driven by combination of changes in response to the health and social care devolution agreement, the devolution of powers over wider public services, the election of a new mayor, or earlier steps to improve population health prior to devolution.

"The findings support the suggestion that devolved systems are able to more closely identify and address the needs of local populations. However, further research is required to understand the mechanisms behind the estimated effect."

Co-author Professor Matt Sutton from The University of Manchester and Deputy Director of the National Institute for Health and Care Research (NIHR) Applied Research Collaboration Greater Manchester (ARC-GM) said, "In Greater Manchester many more people die younger than in most other parts of the U.K.; many others suffer more from serious diseases.

"However, this study has shown that devolution in Greater Manchester could improve things for the better."

Following devolution, the Greater Manchester Health and Social Care Partnership (GMHSCP) was established to set strategy and oversee its delivery, including the delivery of Taking Charge, the region's five year plan.

And also part of the health and social care devolution settlement, NHS England granted the region control of its share of the national sustainability and transformation fund.

The GMHSCP policy priorities also formed components of The Greater Manchester Strategy; a plan produced by Greater Manchester Combined Authority on behalf of Greater Manchester partners, to transform and integrate public services within the conurbation.

Co-author Dr. Yiu-Shing Lau from The University of Manchester said, "These findings may provide clues to the potential success or failure of Integrated Care Systems in England.

"However, there are key differences that should be considered when drawing comparisons between the setup of the GMHSCP and the organization of Integrated Care Systems outlined in the Health and Care Act 2022.

"Similar improvements in population health may not be replicated in Integrated Care Systems without a comprehensive representation of councils on their board.

"The success of future devolution reforms may therefore depend on other factors beyond the types and strength of powers devolved to a health system, including the extent to which health and wider public services are aligned.

"Future research will seek to further investigate the findings of the study by evaluating the impact of devolution on a range of outcome measures and investigating the activities in Greater Manchester that may have contributed to the observed change in life expectancy"

The paper, "The effect of devolution on health: a generalised synthetic control analysis of Greater Manchester, England," is published in The Lancet Public Health.

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Denmark has topped the International Institute for Management Development's seventh annual World Digital Competitiveness Ranking – an assessment of 63 nations' "capacity and readiness to adopt and explore digital technologies as a key driver for economic transformation in business, government and wider society."

The Institute (IMD) with its World Competitiveness Center claim to be an independent academic institution that aims to develop leaders. The Digital Competitiveness Ranking assesses three main factors, listed below:

•     Knowledge – Know-how necessary to discover, understand and build new technologies;
•     Technology – Overall context that enables the development of digital technologies;
•     Future Readiness – Level of country preparedness to exploit digital transformation.

The IMD also considers additional nine sub-factors that mark nations against 54 criteria.

Up until this year, the USA is the only nation to have topped the Rankings. Denmark finally toppled the champ thanks to an exceptional rating on the Future Readiness factor.

The Ranking mentions plenty of problems in the USA, which ranked ninth in the world on the Technology factor but slipped from third to tenth in IT integration capacity. Fears that business is not handling cybersecurity well contributed to the nation's decline.

Among major Reg-reading nations, the UK dropped two places to 14th despite its Technology and Future Readiness scores improving. Other nations improved more markedly, with Israel jumping two places to thirteenth. Twelfth-placed Australia surged six spots up the chart.

India talks a good game about its many digital government services and IT services industry – but was ranked 44th.

Canada jumped three spots to 10th, while Germany dipped to 18th after placing 16th in the last Ranking.

Taiwan's 11th place handily beat China's 17th ranking, though both nations went backwards over the last year.

European nations – Denmark, Sweden, Switzerland, Netherlands and Finland – occupied five of the top ten positions. Three Asian nations – Singapore, South Korea and Hong Kong – made the top ten.

Hong Kong, however, fell seven places to ninth. The sudden shutdown of democracy can do that to a country.

Croatia made the biggest jump, with a 12-slot surge taking it to 43rd place.

Japan's efforts to end its reliance on floppy disks and faxes appear not yet to have seen its digital capacity increase – the nation dropped one place to 29th. Italy is the worst-ranked of the G7 group of very rich and well-developed nations, at 39th place.

Argentina, Colombia, Botswana, Mongolia and Venezuela took the final five slots in the rankings.

The full rankings can be found here. ®

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WASHINGTON — The United States and Russia are tussling over control of a United Nations organization that sets standards for new technologies, part of a global battle between democracies and authoritarian nations over the direction of the internet.

American officials are pushing more than 190 other member countries of the International Telecommunication Union, a U.N. agency that develops technical standards for technology like cellphone networks and video streaming, to vote on Thursday for Doreen Bogdan-Martin, a longtime American employee, to lead the organization. She is running against Rashid Ismailov, a former Russian government official.

The American campaign has been especially intense. President Biden endorsed Ms. Bogdan-Martin last week, capping months of public and private lobbying on her behalf by top administration figures and major U.S. corporate groups.

Whoever leads the I.T.U. will have power to influence the rules by which new technologies are developed around the world. While the organization is not well known, it has set key guidelines in recent years for how video streaming works and coordinates the global use of the radio frequencies that power cellphone networks.

The election has become a symbol of the growing global fight between a democratic approach to the internet, which is lightly regulated and interconnected around the world, and authoritarian countries that want to control their citizens’ access to the web. Russia has built a system that allows it to do just that, monitoring what Russians say online about topics like the invasion of Ukraine, while the United States largely does not regulate the content on social networks like Facebook and Twitter.

Some worry that Russia and China, which also has closed off its internet, could use the I.T.U. to reshape the web in their images. The two countries put out a joint statement last year calling for preserving “the sovereign right of states to regulate the national segment of the internet.” They said they were emphasizing “the need to enhance the role of the International Telecommunication Union and strengthen the representation of the two countries in its governing bodies.”

Erica Barks-Ruggles, a State Department official and former ambassador to Rwanda who is representing the United States at an I.T.U. conference this week, said the organization would help determine if people around the world could have affordable access to new technology and communicate across borders, and “whether their governments are able to disconnect them from the internet or not.”

“That’s why we’re putting time, money, energy into this,” she said.

The I.T.U. was founded in 1865 to tackle issues involving telegraph machines. It traditionally focused on physical networks rather than the internet, but has become involved in setting standards for everything from smart home devices to connected cars. The agency’s plenipotentiary conference, which takes place every four years, began on Monday in Bucharest, Romania.

Last week, Mr. Biden said Ms. Bogdan-Martin “possesses the integrity, experience and vision necessary to transform the digital landscape.” Secretary of State Antony Blinken, Commerce Secretary Gina Raimondo and other senior administration officials have also backed her candidacy.

At a recent conference in Kigali, Rwanda, the United States hosted a reception at the city’s conference center where attendees heard a pitch from Ms. Bogdan-Martin, saw a video endorsement from Vice President Kamala Harris and listened to music from a local band.

In response to emailed questions, Ms. Bogdan-Martin said she hoped her leadership of the I.T.U. could expand global access to the internet and improve transparency at the organization. She said she hoped to lead in “bringing an open, secure, reliable and interoperable internet to all people around the world.”

Moscow is supporting Mr. Ismailov, a former deputy minister for telecom and mass communications for the Russian government and a former executive at Huawei, the Chinese telecommunications company that American officials worry could leak data from its products to Beijing.

The Russian Embassy in Washington did not respond to a request for comment.

The proxy battle of the election may be the first of many more.

“I see the U.S. really engaged in a new kind of foreign policy attack, where they see our adversaries and our competitors are wanting to change the rules of the game to shut off access,” said Karen Kornbluh, a senior fellow at the German Marshall Fund.

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As a meteorologist, Hurricane Ian is the nightmare storm I worry about most

It was a political stumble that turned into a policy two-step. In a 60 Minutes interview, US President Joe Biden declared the Covid pandemic over. Within 12 hours, public health officials, including in his own administration, weighed in to say “No, it’s not.” And within 12 hours after that, the White House—somewhat—walked his comments back.

Chalk it up to exuberance—the updated boosters were just rolling out—or to pandemic fatigue. But look past the immediate messaging failure, and the episode poses an important question: If the pandemic isn’t over yet, how will we know when it is?

It’s a question that can be countered with layers of answers. Official pronouncements for instance: The World Health Organization says “We are not there yet, but the end is in sight,” while the Department of Health and Human Services notes that the US remains in a public health emergency that could be redeclared next month. Or metrics, for example: According to data from the Centers for Disease Control and Prevention, cases, hospitalizations, and deaths are all declining—but at the same time, Covid has been ranked the third-leading cause of death in the US. Meanwhile, only a third of US residents who are over 50, and thus considered at higher risk of illness, have taken the full four-shot vaccine protocol. As of last week, only 4.4 million people—1.5 percent of those eligible—had received the newest bivalent booster.

Look past that mess of contradictions, and beyond them lies a difficult reality: We might never achieve a benchmark that lets us declare the pandemic is behind us. The best “over” we may be able to hope for is that it settles into an endemic state, present but no longer overwhelming. Worst case: It persists, but we cease to care.

“There’s no exact point at which we can say, ‘OK, we’re done,’” says Jennifer Kates, a health policy analyst and senior vice president at the Kaiser Family Foundation. “And that’s hard, because people want certainty. Where we are today is very different than where we were a year and a half ago, when the vaccines were new. But we are still at a place where there is an unacceptably high number of deaths—almost 400 a day, three or four times higher than a really bad flu year.”

Humans live by stories, and we especially like stories that end happily; it’s alluring to think of the pandemic as a storm that shakes your house but then blows through and reveals blue sky. But the more accurate narrative may be a storm that cracks a seawall holding back the ocean—and ever after, your tap water tastes the tiniest bit like salt.

“There’s no going back to 2019,” says Abraar Karan, a physician and infectious-disease researcher at Stanford University who studies the role of air filtration in reducing infection. “The dead aren’t coming back. The long-term consequences won’t be fully appreciated until we have more time to analyze them. And the variants aren’t going away.”

When the pandemic began, we could imagine that the restoration of specific things we’d put on hold would signal life was returning to normal. Schools would reopen; masks would come off; offices would fill back up, and restaurants would buzz with diners. Thirty months on, we got all those things back—social mixing, return to office, bare faces—without vanquishing the virus. If their return was not the signal, it’s difficult to imagine what could be.

“There won’t be a single moment,” says Caitlin Rivers, an assistant professor at the Johns Hopkins Bloomberg School of Public Health and part of the founding leadership at the CDC’s new epidemic forecasting center. “We will recognize the transition only in retrospect.” But among possible milestones—interrupting transmission, suppressing hospitalizations and deaths, relaxing self-sequestering—she points out that we’ve only achieved the third one. “The last dimension that I think about in moving from emergency to routine is when people live their lives in the way that they wish to,” she says. “And I think on that point, we may be close to there.”

That makes moving on from the pandemic a sociopolitical decision rather than an epidemiological one. While it’s not clear whether SARS-CoV-2 can settle into a steady state alongside humanity, we can be pretty confident it hasn’t done that yet. On the same weekend that Biden was declaring the pandemic over, Swedish researchers announced in a preprint (not yet peer-reviewed) that they had identified yet another viral variant, dubbed BA.2.75.2. Ben Murrell, the preprint’s senior author, said on Twitter that it “exhibits more extreme antibody escape than any variant we’ve seen so far,” meaning that existing vaccines—possibly including the brand-new Omicron bivalents—might not successfully suppress it.

It’s unnerving to recognize that we might be done with Covid, but Covid might not be done with us. It evokes the Groundhog Day feeling of making yet another exhausting circuit through a series of identical events. Except, of course, the moral of Groundhog Day is that sincere intention can change the future. There are lessons within the pandemic that we could leverage. We just haven’t taken advantage of most of them.

“In 2020, as awful as it was, I thought: This is finally the time that we’re going to end the cycle of boom and bust—because this event is so profound that we are not going to want to come out of it and just head right back into another one,” says Jennifer Nuzzo, an epidemiologist and director of the Pandemic Center at Brown University School of Public Health.

But in fact, though the US spent trillions on Covid—in stimulus funds, business rescues, health care subsidies, and vaccine research—things that could make a difference to the next pandemic have yet to be created. Those include funding state and local health departments so they can build back permanent workforces, and reconsidering the health care cost-cutting that left understaffed hospitals so vulnerable to Covid overcrowding. It also includes fixing the collection of disease data in the US. The pipeline is so leaky thanks to incompatible forms and platforms that a coalition of public health organizations estimate it would take almost $8 billion to repair. One recent example of the system’s ineffectiveness: In many states, men who believed themselves at risk for monkeypox, but who also thought they might have been protected by childhood smallpox vaccinations, discovered their paper vaccination records had never been added to digital systems.

Another way to ascertain when the pandemic is over is to ask whether we’re ready for the next one. About that: We’re not. “That is not one of my indicators, because I don’t think we’re ready for the next pandemic,” Kates says. “And I don’t think we’ll be ready for a long time.”

Which might sound defeatist. But another way to think about getting to “over” is to imagine what actions it would take to suppress Covid as much as possible, and then make them milestones that lead us to the pandemic’s end. “To me, it will be ‘over’ when there’s little left that we can do,” Karan says. “But there are very doable things we can do right now, between closing the booster gap for severe disease and death, to air filtration to reduce super-spreading. And they’re not going to get done if the political will is not behind it.”

When Will the Pandemic Truly Be ‘Over’?

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Ship that warned Titanic of icebergs has been found at bottom of Irish Sea

In 2001, Marcus Raichle, a neurologist at Washington University, ran such an experiment—and he noticed an odd consistency in the brain states of participants in his study. The fact that they were exhibiting similar brain states was not unusual by itself. After all, performing specific tasks means similar regions of the brain will be engaged for each person. However, the unusual thing was that the overlap occurred when participants weren’t really doing anything at all. While establishing a baseline resting state in the scanner, the participant’s brains showed a surprising amount of similarity. It was like discovering that a bunch of random computers all featured a very similar screensaver.

Subsequent studies revealed that the default mode network, as it came to be known, was involved in thoughts about one’s identity, replaying memories, theorizing about the intentions of other people, and thinking about the future. This is your mind when you’re spacing out or daydreaming. In short, when we are not doing much of anything at all, we tend to be weaving the story of our lives.

 Your brain’s default mode network engages when your mind is in its resting state. Wikimedia Commons

© Provided by The Daily Beast

This has significant evolutionary implications. Our ability to conceive of ourselves in relation to others and the world allows us to strategize, predict, and plan against the circumstances that may lead to our downfall, whether that is our social status within the tribe or our actual death. In the book Buddha’s Brain, psychologist Rick Hanson and neuroscientist Richard Mendius explained how one’s ability to construct a self “has been stitched into human DNA by reproductive advantages slowly accumulating across a hundred thousand generations.”

Yet our ability to engage in self-absorbed daydreaming has drawbacks. For one, thinking about preserving who we are can manifest as anxiety. A 2011 study by Harvard researchers Matthew Killingsworth and Daniel Gilbert found that people engage in mind wandering about 47 percent of the time, and it’s also correlated with unhappiness. The study essentially pinged 2250 people at random throughout the day on their phone and asked them what they were doing, how they were feeling, and whether they were thinking about what they were doing or thinking about something else. Regardless of the activity, people reported being less happy when their minds were wandering than when they were not. Further research found that meditation interrupted the default mode network—as do psychedelics. Meanwhile walking in nature was found to interrupt the kind of depressive rumination that is a hallmark of this network.

All this conspired to give the default mode a bad rap. When left to our own devices, the research suggested, we activate our internal worry monsters, creating a fortified wall between ourselves and our experience.

As is often the case when studying the brain, however, other research revealed alternative perspectives. Humanity wouldn’t quite have thrived to this extent if not for its unique ability to engage in selfish mentation. Knowing ourselves allows us to know others.

In The War for Kindness, Stanford psychologist Jamil Zaki described the default mode as the “untethered mind”—the state in which our brains take a mental trip to the past or future. “The more you engage the brain’s untethering system,” wrote Zaki, ”the deeper you can go, and the better you understand what other people think or feel.”

The journalist Michael Easter described another useful feature of the default mode in The Comfort Crisis. He labeled it “unfocused mode,” and explained how the boredom that produces mind wandering is crucial to creativity, a potential survival benefit that prevents us from repeating the same tasks in the same ways all the time. If you’ve ever had a great idea in the shower, this might ring true.

But all this begs the question: Is the default mode the home of neurotic self-obsession or creative and empathic expression?

Easter points to the modern crush of technology as a trap for our attention—and that’s a big part of the problem. We don’t allow ourselves to unplug, to be bored, and to mind wander. “We spend twelve-ish hours a day using digital media,” he told The Daily Beast. “By persisting through boredom, resisting the pull of the attention, and seeing where our mind takes us, we can come to some deeper insights. And I think there are plenty of anecdotes from creatives supporting this.”

There is research that supports this as well. “Twenty percent of the creative ideas of writers and physicists that we studied happened not while they were at work, or even while they were actively pursuing the problem, but when they were doing something else, and their mind naturally wandered to some sort of solution,” Jonathan Schooler, a neuroscientist at UCSB, told The Daily Beast. His research into the link between mind-wandering and creativity suggests that focusing less might ironically contribute to a widening of the potential scope of the solution.

Schooler’s lab also conducted a follow-up study of the link between mind wandering and unhappiness—and discovered a fascinating distinction. On average, they found that people were less happy when mind wandering. However, there’s a catch. “We found that when people were mind wandering about something that they found especially interesting, they were actually happier,” he said. This has led Schooler to distinguish between mind wandering and what he calls “mind wondering.”

“When you’re mind wandering about negative worries and ruminations, that is going to bring you down,” he explained. “But when you’re mind wondering about curious things that you're fascinated about, that actually can be stimulating for you.”

Judson Brewer, director of research and innovation at the Brown University Mindfulness Center, has researched the link between the default mode, addiction, anxiety, and meditation. He isn’t convinced by this rosier portrayal of the brain’s default mode.

Brewer describes activating the default mode as a tendency to get caught up in a contracted state of mind—meaning a mind that is narrowly focused on something while ignoring the sensory information around it. For example, when you have a creative idea your mind often recognizes that brilliance and the default mode is activated. “But that’s not actually about the creative idea itself,” Brewer told The Daily Beast. It’s about you getting caught up in your own ego. You start to claim the creative idea, defend it, doubt it, get paranoid about someone stealing it, etc. The ego actually becomes a hindrance.

From Brewer’s perspective, happiness, curiosity, and creativity all come from a more expansive state of mind, one in which the default mode is quieted, ego is reduced, and we cease to impede the flow of experience with the dam of identity.

Ultimately, the default mode is simply a network of brain regions that lights up and quiets down depending on a vast range of stimuli. Categorizing it as healthy or harmful might be the wrong way to look at it. We’ve all experienced moments of feeling open, immersed, and elated, as well as closed off, removed, and depressed. We’ve all experienced both stimulating curiosity and abject boredom. Despite their different views, Schooler and Brewer would agree that understanding how the default mode works can be key to understanding how these states arise—and, therefore, understanding what really makes us happy.

Read more at The Daily Beast.

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The four-yearly State of the World's Birds report, which provides a snapshot of the plight of species globally and more broadly a barometer for biodiversity, comes as the United Nations steers an international process to protect nature.

"One in eight bird species is threatened with extinction, and the status of the world's birds continues to deteriorate: species are moving ever faster towards extinction," said the report released this week by BirdLife International.

Using data from the International Union for Conservation of Nature (IUCN), the report said 49 percent of bird species worldwide have declining populations, with populations falling even in species not normally rare or at risk.

Roughly 13 percent are considered threatened.

The main threats include the growth of unsustainable agriculture, logging, invasive species, over-exploitation and climate change.

Most bird populations face a combination of human-caused threats.

"The natural world is in trouble. Human actions are driving species rapidly towards extinction, undermining ecosystem functions and services vital to our own survival," the report said.

BirdLife International, which has decades of survey data, said there are now 2.9 billion fewer individual birds in North America than there were in 1970, an estimated drop of 29 percent.

The European Union has seen a net loss of around 600 million birds, roughly 18 percent since 1980.

In both cases, the losses are most acute among long-distance migrants and farmland birds.

Birdlife said many key bird preservation zones were in a poor state and called for a global push to protect and restore habitats.

In December, nations gather to finalise a treaty to halt the decline of biodiversity and set humanity on a path to "live in harmony with nature" by mid-century.

BirdLife International chief Patricia Zurita said the framework under negotiation was "the world's best and perhaps last chance to halt the loss of nature" and restore biodiversity.

"The birds and the rest of nature are depending on us. And we are depending on them," she said.

© 2022 AFP

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Chromosomes, incredibly long DNA molecules, were pictured as knotted up like stray balls of yarn resembling a gel. But a new study by scientists from CNRS, Institut Curie, and Sorbonne Université suggests that Chromosomes are fluid – almost liquid – outside their division phases.

For the first time, scientists managed to manipulate chromosomes in the nucleus of living cells physically. The observations offer a very different image. Chromosomes are flexible and able to move freely; they are not constrained by other components of the nucleus and can reorganize themselves.

This work was done in collaboration with the Nuclear Dynamics, Physical Chemistry and Cell Biology, and Cancer1 laboratories and scientists from MIT. They attached magnetic nanoparticles to a small portion of a chromosome in a living cell.

Then, using a small magnet outside the cell, they stretched the chromosome to varying degrees of tension. Scientists could determine a chromosome’s response to outside pressures by utilizing this method for the first time in a living cell.

Through these experiments, the scientists demonstrated that a chromosome’s conformation could be significantly changed by the range of forces normally present in the nucleus, such as those exerted by enzymes that replicate DNA.

Scientists noted, “This significant finding at the interface between physics and biology changes the conventional understanding of chromosomes. It also offers new information to our understanding of chromosome biophysics, the structure of the genome, and biological activities.”

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Ever felt your phone buzz in your pocket, then pulled it out to find no text, no call, no notification? You might be experiencing ‘phantom vibration syndrome’– and you’re not alone. According to one study, 9 out of 10 undergraduates said they had experienced the phenomenon in the last week or month.

Scientists aren’t exactly sure why these tactile hallucinations happen to so many of us. One leading theory is that our excessive smartphone use, and our creeping sense that we should be constantly available, have conditioned our brains to overinterpret sensations such as clothing moving against our skin. On the plus side, most people don’t find the phantom signals bothersome.

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During adolescence, important structural and functional changes occur in the brain, especially in the prefrontal area, which plays a major role in controlling attention. On the other hand, omega-3 unsaturated fatty acids are known to be critical for proper brain development and function. The most abundant fatty acid in the brain, particularly in the prefrontal area, is DHA, which is mostly supplied by eating fatty fish.

"Despite the established importance of DHA in brain development, few studies have evaluated whether it plays a role in the attention performance of healthy adolescents," says Jordi Júlvez, IISPV researcher, ISGlobal research associate and coordinator of the study. "In addition, the possible role of alpha-linoleic acid (ALA), another omega-3 but of plant origin, has not been as extensively studied." This is relevant, given the low fish consumption in Western societies.

The purpose of this study was to determine whether a higher intake of DHA and ALA was associated with an increased attention performance in a group of 332 adolescents from different schools in Barcelona. The participants underwent computerized tests that measure reaction times in order to determine selective and sustained attention capacity, inhibition capacity in the face of distracting stimuli, and impulsivity. The adolescents also answered a series of questions on dietary habits and gave blood samples to measure red blood cell levels of DHA and ALA—an objective and valid indication of long-term dietary intake of these fats.

The results show that higher levels of DHA are associated with greater selective and sustained attention and inhibitory attention. In contrast, ALA was not associated with attention performance, but was associated with lower impulsivity. "The role of ALA in attention control is still unclear, but this finding may be clinically relevant, as impulsivity is a feature of several psychiatric conditions, such as ADHD," explains Ariadna Pinar-Martí, first author of the study.

"Our study indicates that dietary DHA most likely plays a role in attention-requiring tasks, but further studies are needed to confirm a cause-effect, as well as to understand the role of ALA," concludes Júlvez. In any case, the findings add to the already existing evidence on the benefit of consuming fatty fish (the main source of DHA) at a time when the brain is developing in its highest sophistication before reaching adulthood.

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Unusual Ebola strain kills 23 in Uganda; no vaccines, treatments available

Physicist Ranga Dias at the University of Rochester in New York State and his collaborators stirred interest but also caution with a 2020 Nature paper1 that reported the creation of a superconductor that worked at an unprecedented temperature of 15 ˚C. The material was a mix of carbon, hydrogen and sulfur, but to conduct electricity without resistance it had to be squeezed between two diamond tips to 2.6 million times greater than atmospheric pressure.

Superconductors can carry large electric currents without producing any waste heat, and are key to many scientific and medical applications, as well as potentially to future energy-saving technologies. But most superconductors work only at temperatures approaching absolute zero (–273 ˚C). Only in recent years have physicists managed to get some to work above 0 ˚C using high-pressure anvils.

Dias’s team “used a non-standard, user-defined procedure” in subtracting noise from experimental data shown in two figures, according to the retraction notice published2 on 26 September. “The details of the procedure were not specified in the paper and the validity of the background subtraction has subsequently been called into question.”

Through a spokesperson, Dias said that he and his colleagues disagree with the retraction and stand by their results. They will resubmit the paper to Nature with the raw-data plots of the figures. “The retraction request does not question the observed physical superconductivity state of the [carbon-sulfur-hydrogen] material,” says Dias’s statement. He pointed to an arXiv preprint posted4 in 2021 that responds to researchers’ concerns and presented the raw data, and added that three teams had replicated elements of the results.

The retraction follows the publication in Nature of a response4 to the original paper by physicists Jorge Hirsch of the University of California, San Diego, and Frank Marsiglio at the University of Alberta in Edmonton, Canada. The two had raised multiple questions about the study, in particular regarding the two figures mentioned in the retraction notice. These reported a drop in a feature called magnetic susceptibility when the material was cooled below a critical temperature — which is supposed to be a tell-tale sign of superconductivity. Several other publications had also questioned the claim, as did other physicists who pointed out some of these same issues in interviews with Nature’s news team at the time of the original publication.

“The retraction is dramatic but the correct decision,” says Mikhail Eremets, a physicist at the Max Planck Institute for Chemistry in Mainz, Germany, of the retraction. The field will now be able to move on from what has been a two-year-long controversy, he adds. “Scientists will have more time to work on real stuff.” Eremets’s laboratory has tried, unsuccessfully, to reproduce the results by Dias’s team, and he and his co-authors had already decided to stop citing the now-retracted paper.

doi: https://doi.org/10.1038/d41586-022-03066-z

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On September 7, 1674, Antonie Van Leeuwenhoek, a fabric seller living just south of The Hague, Netherlands, burst forth from scientific obscurity with a letter to London’s Royal Society detailing an astonishing discovery. While he was examining algae from a nearby lake through his homemade microscope, a creature “with green and very glittering little scales,” which he estimated to be a thousand times smaller than a mite, had darted across his vision.

Two years later, on October 9, 1676, he followed up with another report so extraordinary that microbiologists today refer to it simply as “Letter 18”: Van Leeuwenhoek (lay-u-when-hoke) had looked everywhere and found what he called animalcules (Latin for “little animals”) in everything.

He found them in the bellies of other animals, his food, his own mouth, and other people’s mouths. When he noticed a set of remarkably rancid teeth, he asked the owner for a sample of his plaque, put it beneath his lens, and witnessed “an inconceivably great number of little animalcules” moving “so nimbly among one another, that the whole stuff seemed alive.” After a particularly uncomfortable evening, which he blamed on a fatty meal of hot smoked beef, he examined his own stool beneath his lens and saw animalcules that were “somewhat longer than broad, and their belly, which was flat-like, furnished with sundry little paws”—a clear description of what we now know as the parasite giardia.

With his observations of these fast, fat, and sundry-pawed creatures, Van Leeuwenhoek became the first person to ever see a microorganism—a discovery of almost incalculable significance to human health and our understanding of life on this planet.

Microorganisms are the second most abundant life-forms on Earth. Two of the types that Van Leeuwenhoek identified—protozoa and bacteria—are by some estimates responsible for more than half the deaths of every human who has ever lived, and yet until he observed them their existence had hardly been seriously postulated, much less proven. Of course, he had no idea about the pivotal role his little animals played, but his revelation provided the foundation for germ theory—the greatest leap forward in the history of medicine. Even more surprising, this monumental discovery was not made by one of the 17th century’s great scientific minds such as Galileo or Isaac Newton. Instead, a secretive, obsessive, self-taught Dutchman of little renown did it by handcrafting a lens 10 times more powerful than anything built before it. His design wouldn’t be bested for another 150 years.

Yet even as scientists steadily unlocked the secrets of Van Leeuwenhoek’s microworld over the past 350 years, one great mystery eluded them: How the hell did he do it? How did a shopkeeper working during his off hours build a microscopic lens that surpassed the world’s greatest by an order of magnitude?

While Leeuwenhoek shared nearly everything he saw through his microscope in exactingly detailed letters, he zealously guarded how he made his revolutionary lens. When asked, he declined or obfuscated. Even as his discoveries made him so famous that the King of England requested to see his animalcules and Peter the Great stopped in Delft to see his lenses, the Dutchman never revealed his secrets.

Van Leeuwenhoek crafted more than 500 microscopes, but only 11 of his instruments survive today—and only one that produces the 270X magnification he used to make his greatest discovery. Because that lens remains sandwiched between brass plates, determining its mode of manufacture would require disassembling the microscope—an affront tantamount to scraping paint off the Mona Lisa to determine the sequence of Leonardo’s brush strokes.

Most of Van Leeuwenhoek’s contemporaries believed he had invented a new glassblowing technique. Clifford Dobell, who wrote the brilliant 1960 biography Antony Van Leeuwenhoek and His Little Animals, postulated that he created his best lenses by simply grinding and polishing them better than anyone else. But in three centuries of speculation, no one could say for sure.

Tiemen Cocquyt’s interest in Van Leeuwenhoek’s secrets began in the late 2000s, soon after first seeing one of his microscopes, which was then locked away in the basement of the University Museum Utrecht. “How could this toy open up the microworld?” Cocquyt remembers thinking.

Cocquyt is a curator in the National Museum Boerhaave in Leiden, Netherlands, which houses an array of early optical instruments, including several of the microscopes. He has spent much of his career investigating the origins of Europe’s 17th-century optical revolution, when visual instruments suddenly leaped from simple magnifiers to the great telescopes of Galileo and Christiaan Huygens. (That revolution was inadvertently sparked, Cocquyt says, by Italian advances in making ultra-clear glass.)

Over Zoom, Cocquyt shows me a replica of a Van Leeuwenhoek microscope, and it does look like a toy—a doll’s hand mirror, to be exact. It’s barely 3 inches tall, with a thin handle leading to a square brass plate. The lens sits beneath a pinhole in the plate’s center, and on the back side a pin for holding samples is connected to a set of screws for focal adjustment.

When Cocquyt first examined the exposed glass of the lens, he believed its smooth surface indicated it could only have been created by heat. Thus, like many of Van Leeuwenhoek’s contemporaries, he suspected the Dutchman had invented a new glassblowing technique. But without looking inside, he could only speculate.

The definitive answer, he hoped, might be found with the help of a nuclear reactor.

At its simplest, a magnifying lens is nothing more than a curved piece of transparent material—usually glass. As light passes through that angled glass, it decelerates, and its path is redirected, or refracted. Depending on its design, a lens can manipulate light in any number of ways, but magnifying lenses like Van Leeuwenhoek’s are spherical—technically called bi-convex—and refract light into a single focal point. “In essence, it serves as a light funnel,” says Steve Ruzin, curator of the Golub Collection of antique microscopes at UC Berkeley. Place your eye at the narrow end of the funnel, and an enormous amount of light arriving from the lens’s focal point crams through your pupil.

This has two effects. First, the more light your eye receives from an object, the more detail it can perceive. Second, by funneling all the light hitting the lens through the width of your pupil, the image consumes your entire field of view. An object that once projected onto your retina as an undetectable speck now appears in Imax.

Of course, not all spherical lenses magnify equally. A big lens with a gentle curve refracts the light traveling through it only slightly, and thus barely enlarges the image. A small lens with a sharp curve refracts the light more, enlarging the image a great deal. Moderately powered spherical lenses of the 17th century were about the size of a pea. Van Leeuwenhoek’s greatest lenses were smaller than a sixth that size. At that diameter, construction becomes exceptionally difficult. Even the smallest manufacturing defect—a bubble, scuff, or scratch—could project an enormously disfiguring visual aberration. Larger, less powerful lenses are far more forgiving. They are simple enough to create that they’ve been found among remnants of the oldest civilizations. The earliest-known handcrafted lens is a piece of ground rock crystal capable of 3X magnification that archeologists discovered in a nearly 3,000-year-old Assyrian palace. But because glass occurs naturally, its magnifying power has probably been independently discovered and harnessed many times throughout history.

Nevertheless, lenses never exceeded much beyond the power of typical modern reading glasses until the early 1590s, when a Dutch lens maker named Hans Janssen built a microscope capable of 9X magnification. Janssen’s contraption inspired many copycats, one of which intrigued Galileo, who modified one of his own telescopes to produce a microscope that one witness claimed could show “flies which appear large as a lamb.”

In 1665—only a few years before Van Leeuwenhoek peered through his first lens—microscopes emerged into the public consciousness when the polymath Robert Hooke published his surprise bestseller Micrographia. The book included Hooke’s observations, interpretations, illustrations, and even simple instructions on how anyone could make their own lenses: Hold a thin hair of glass over a flame until a bead forms, “which will hang at the end of the thread,” writes Hooke. Snap off the bead, and the result is a spherical magnifier.

But despite the prodigious genius of Galileo and Hooke, neither produced lenses with anything close to the magnifying power of Van Leeuwenhoek’s. “Leeuwenhoek took an opportunity that lay somehow undeveloped in the 1660s and pushed it into the best result that was possible,” Cocquyt says.

He did so by first eschewing Hooke’s and Galileo’s preference for using multiple lenses arranged in sequence. This design is common in modern microscopes—it’s a bit like projecting an image into another projector—but achieving that magnifying effect without producing huge distortions requires extreme precision. Until that challenge was solved in the early 19th century, single-lens microscopes like Van Leeuwenhoek’s could achieve far superior results.

Hooke was aware of this shortcoming in his design, yet he still preferred multiple lenses, thanks in part to their ease of use. High-powered lenses have such an extremely short focal point that with just one, the viewer has to place their eye incredibly close to the lens, making blinking difficult. Hooke wrote that he found single-lens microscopes “offensive to my eye.” Ruzin told me that looking through one of Van Leeuwenhoek’s surviving devices is “terribly uncomfortable.”

Van Leeuwenhoek’s design may have been torture to use, but it was also brilliant—and that brilliance extended beyond his super-powered lenses. Because his device was handheld, he could backlight his sample by holding it up against sunlight or a flame, while his contemporaries’ desk-bound microscopes could only be lit from above. Top-down lighting works well for opaque objects, such as a bee’s stinger, but not for pond water and other translucent samples, where it’s far easier to see microorganisms. To observe these liquids, Van Leeuwenhoek filled a small glass capsule, glued it to the microscope’s pin, and held the instrument up to light.

“It almost seems as if Van Leeuwenhoek knew that a new microworld was to unfold,” Cocquyt told me. One of his scientific rivals, Johannes Hudde, later said, “isn't it surprising that we never had the creativity to use these ball lenses to observe little things against the daylight, and that an uneducated and ignorant man such as Van Leeuwenhoek had to be the one to teach this to us.”

Van Leeuwenhoek was the fifth son of a basket maker, born in the Delft—a small port city in South Holland known for its picturesque waterways, pottery, and beer. At 16 he departed for an apprenticeship as a dry goods seller in Amsterdam, but six years later he returned home, married the daughter of a well-regarded local brewer, and purchased his own fabric shop.

He spent his twenties growing a successful business but suffered immense personal tragedy. Of the five children he and his wife Barbara had in their 12 years of marriage, four died in infancy; Barbara would soon follow. Few biographical details have survived from his first decade back in Delft, but he held a number of odd jobs in addition to running his draper shop, including working as chief custodian of the local courthouse. A stint as town surveyor offers one clue to Van Leeuwenhoek’s budding scientific potential: proof he had learned geometry.

His obsession with magnifying lenses began sometime in his mid-thirties. How he came upon it isn’t known. His writings never touch on its origins. Perhaps, as many have speculated, he started using lenses to inspect the quality of his cloth. Or maybe he got caught up in the public mania for microscopes following the publication of Hooke’s Micrographia. Van Leeuwenhoek never mentions the book in any of his letters, but the timing aligns, and he clearly read it: Some of his experiments replicate Hooke’s too closely to be a coincidence. But regardless of how Van Leeuwenhoek got into microscopy, by 1668 he had begun pursuing it with an unusual tenacity. While traveling in England that year, he saw the white cliffs of Dover and felt compelled to examine their chalky slopes beneath his lens: “I observed that chalk consisteth of very small transparent particles; and these transparent particles lying one upon another, is, methinks now, the reason why chalk is white.”

By 1673, though still operating in complete obscurity, he was already making the world’s most powerful lenses. His obscurity might very well have continued, and the momentous discovery of microorganisms might well have served only to satisfy this curious individual’s psychological compulsion, were it not for a Delft physician named Renier de Graaf.

De Graaf had come to some renown through his experiments using dyes to determine organ function, and in 1673 he introduced Van Leeuwenhoek to the Royal Society with a note calling him a “most ingenious person … who has devised microscopes which far surpass those which we have hitherto seen.” Following that preamble, Van Leeuwenhoek described the body parts of a louse in his precise-yet-meandering writing style that is, as one biographer notes, “distinguished with a certain business formality, but an almost total lack of coherence.” Over the next year, he sent five more letters to the Royal Society conveying interesting but not particularly controversial observations about the globules in milk and the structure of his fingernails. Then, on September 7, 1674, he sent the letter reporting his shocking discovery: Within an otherwise unremarkable drop of pond water he had seen “glittering” creatures a thousand times smaller than any animal he had previously observed.

The Society’s secretary, Henry Oldenburg, replied to Van Leeuwenhoek with understandable restraint: “This phenomenon, and some of the following ones seeming to be very extraordinary, the author hath been desired to acquaint us with his method of observing, that others may confirm such observations as these.” Van Leeuwenhoek quickly responded, providing eyewitness accounts of a few local dignitaries who had looked through his lenses—but refused to disclose the secrets of his techniques. “My method for seeing the very smallest animalcules and minute eels, I do not impart to others; nor how to see very many animalcules at one time. That I keep for myself alone,” he wrote. Even when Hooke himself, who learned to speak Dutch just so he could communicate with Van Leeuwenhoek without translation, specifically asked how he made his observations, the stubborn scientist refused for reasons that were, as Hooke later wrote, “best known to himself.”

Three years later, after a few failed attempts by others, Hooke finally managed to re-create Van Leeuwenhoek’s experiment well enough to prove his observations at a gathering of the Royal Society. The confirmation made the Dutch draper famous, but despite repeated inquiry he took his secrets to the grave.

In 2018, Cocquyt and his team of researchers set out to reveal them without taking Van Leeuwenhoek’s 350-year-old microscope apart. That’s where the nuclear reactor comes in.

Neutron tomography is a scanning technique that is as remarkable as it is completely insane. It involves blasting neutrons generated by atomic collisions through a large-caliber barrel—which sticks out of a reactor’s nuclear chamber like the devil’s cannon—and into whatever object needs scanning. Neutrons, beyond irradiating everything they hit, pass right through metals but slam into most low-mass elements, including those in glass. Sensors behind the object detect the neutrons, producing an image that reveals their inner structure. Recent scans have led to the discovery of a dinosaur inside another dinosaur's belly and the remnants of ice in martian meteorites.

A nuclear reactor in Van Leeuwenhoek’s hometown of Delft had recently installed a neutron tomography instrument, and Cocquyt used it to examine the Dutchman’s lenses in their birthplace. He first placed a replica microscope in front of the neutron scanner—a test to ensure he didn’t render a priceless piece of scientific history radioactive for 1,000 years. When he next scanned the inventor’s less-powerful microscopes, the images clearly showed the glass to have hard edges and a slight lentil shape. “Exactly what you would expect for a ground lens,” Cocquyt says.

But on his most powerful lens, neutron tomography revealed that Van Leeuwenhoek used another technique entirely. It was almost perfectly spherical and completely smooth, without the sharp rim inevitably created by a traditional grinding cup. Even more tellingly, the lens retained the faint remnants of a snapped stem, concealed by the brass plates since the day Van Leeuwenhoek had placed it there.

The stem is a smoking gun. It’s the unavoidable result of forming a lens by melting a thread of glass until a bead forms on its end and then snapping it off. In other words, to make his greatest lens, Van Leeuwenhoek copied Hooke’s simple recipe from the book that likely inspired him. Cocquyt believes this may explain why he was so circumspect when Hooke asked about his methods; he wanted to avoid giving credit to Hooke himself.

Published in Science Advances last year, Cocquyt’s discovery that Van Leeuwenhoek used a well-known technique reveals a deeper truth about the state of microscopy in the 17th century. It suggests that for all the crafting genius required to make his tiny, super-powered lens, Van Leeuwenhoek’s greatest insight may have been that there was something new to see by making one.

This seems intuitive and incredibly obvious to a modern reader. What kind of scientist wouldn’t want to see in greater detail? But before Van Leeuwenhoek, most microscopists used their lenses to reveal greater detail about the visible world—things they could already see to some degree with the naked eye. Their drawings of bee stingers and ant legs do not lose their resemblance to the creatures readers were familiar with. Had they used Van Leeuwenhoek’s high-powered lenses, their depictions would not have been recognizable to anyone.

Leeuwenhoek had no inkling that minuscule, alien-like creatures awaited him, but his obsession with the microworld drove him to leave the visible world behind and discover a vast new microbial one living under—and inside—our noses.

The Secret Microscope That Sparked a Scientific Revolution

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Ian reaches major hurricane status, will be a historic storm for Florida

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If you have trouble keeping up with the latest particle physics, we don't blame you. The buzzy field has exploded in recent years, with a vast string of highly experimental studies — and a lot of highly inconclusive literature — spawning as a result. You'd be forgiven for assuming that if this much time, money, and effort and is going into one particular realm of study, it must be worth it. Right?

According to former particle physicist Sabine Hossenfelder, the answer, sadly, is wrong.

"It has become common among physicists to invent new particles for which there is no evidence, publish papers about them, write more papers about these particles' properties, and demand the hypothesis be experimentally tested," Hossenfelder, who now works as an astrophysicist, argued in an excoriating essay for The Guardian. "It is wasting time and money."

Big Grain Time

Hossenfelder's case rests on several criticisms of the field, the first being social. Basically, she says, everyone is following the leader. If your peers are receiving grants in the name of far-flung, conceptual, unproven particles, why would anyone opt out? Science isn't cheap, and going against the grain is by nature a far more difficult sell.

But that issue aside, the astrophysicist believes there to be a deeper problem with the race for particle discovery: that particle physicists have "misconstrued" Karl Popper's philosophy of falsifiability, incorrectly interpreting it to mean, as she writes, that "any falsifiable idea is also good science."

In other words, many of her peers have used falsifiability to justify a heft chunk of dead end research, rather than using it as a guideline. And this, in her opinion, has led to the use and study of misinterpreted-and-or-probably-not-real particles as convenient plugs for statistical holes in a number of other theories. A troubling observation, given that, if true, it would mean that a lot of research out there is being held up by nonexistent glue.

"I believe there are breakthroughs waiting to be made in the foundations of physics; the world needs technological advances more than ever before," the astrophysicist explains, "now is not the time to idle around inventing particles, arguing that even a blind chicken sometimes finds a grain."

"It saddens me," she added, "to see that the field has become a factory for useless academic papers."

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The city of skyscrapers soaring above the desert, which imports almost all of its food, has been impacted by rapidly rising consumer prices, a global trend exacerbated by Russia's invasion of Ukraine.

Ten vending machines were installed last week in supermarkets, with a computer touch screen allowing people to select different types: loaves for sandwiches, pitta bread or flat Indian-style chapatis.

The machine has a credit card reader -- for donations not payment.

"A friend told me there was free bread, so I came," said Bigandar, a young man from Nepal who works at a car wash, not wanting to give his full name.

Like millions of Asian migrants, he dreamt of making a fortune in the United Arab Emirates.

He headed for Dubai, a city that has earned a reputation for conspicuous consumption and excess.

According to government figures from the Dubai Statistics Center, the food price index, which tracks the monthly change in the cost of a basket of food commodities, rose by 8.75 percent in July, year on year.

The cost of transport has jumped by more than 38 percent.

'Disadvantaged'

The bread machines are the initiative of a foundation set up by the ruler of Dubai, Sheikh Mohammed bin Rashid Al-Maktoum.

"The idea is to go to disadvantaged families and workers before they come to us," said the foundation's director, Zeinab Joumaa al-Tamimi.
 

Anyone in need can now get hot bread just "by pressing a button", she said.

The oil-rich UAE has a population of nearly 10 million people, 90 percent of them foreigners, many labourers from Asia and Africa.

Dubai, the commercial heart of the UAE, relies on this army of workers to build skyscrapers and for the service sector, from real estate to luxury tourism, on which it has built its reputation.

Bigandar, who has worked there for the past three years, says that for each vehicle he cleans he earns three dirhams, or 81 US cents.

Working hard and with tips from customers, he can earn between 700 and 1,000 dirhams a month ($190-270).

"My employer covers housing and transportation, but not food," he said.

In a sign of the growing difficulties faced by migrant workers, a rare strike was led in May by delivery men demanding better wages in the face of rising fuel prices.

In July, the authorities announced the doubling of social aid, but only for the handful of Emirati families with incomes below 25,000 dirhams per month ($6,800), considered to be disadvantaged households.

This aid programme does not include foreigners.

"Because of inflation and rising interest rates, there are many people whose wages are low and who, with the rising cost of living, can no longer meet all their needs," said Fadi Alrasheed, a Jordanian businessman who has lived in Dubai for 20 years.

According to the UN World Migration Report, the UAE is home to nearly 8.7 million migrants, mainly from India, Bangladesh and Pakistan.

Henley and Partners, a London-based investment migration consultancy, estimates there are more than 68,000 millionaires and 13 billionaires in Dubai, ranking the city the 23rd richest in the world.

© 2022 AFP

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It’s DART’s big day: Asteroid collision just hours away

Report pushes ‘big-tent’ approach for the future of batteries

Asteroid Ryugu was once part of a much larger parent body, new results find

In 2015, Steffanie Strathdee, distinguished professor of medicine and associate dean of global health sciences at the University of California, San Diego (UCSD), was confronted with an antimicrobial-resistant infection the likes of which she had never come across. The patient involved was a man who had developed pancreatitis, an inflammation of the pancreas, but further investigation revealed this was just the tip of the iceberg. A CT scan revealed a large pseudocyst—a sac inside the man’s abdomen—that had likely been there for months. The pseudocyst had offered a perfect environment to harbor bacteria, and it had become home to a particularly nasty bug: a multidrug-resistant strain of Acinetobacter baumannii, a bacterium that tops the World Health Organization’s priority list of pathogens for which new antibiotics are critically needed. 

In this case, the infection was resistant to almost all antibiotics, with just partial sensitivity to a few “last-resort” drugs that are reserved for the most serious resistant infections and come with the risk of hefty side effects. Faced with an infection that was rapidly getting worse, Strathdee was desperate to find a solution that might save the man’s life. It was particularly crucial to her because this wasn’t just any patient. It was her husband.

Strathdee and her husband, Thomas Patterson, had been on holiday in Egypt when things had started to go wrong. They’d just enjoyed a final dinner on their trip, a romantic meal under the stars aboard a cruise ship on its way to Luxor, when Patterson had begun to feel unwell. He then vomited through the night. “I just thought he had food poisoning, and I was a bit annoyed because he was keeping me up,” Strathdee says. But as the night turned to morning and Patterson’s condition worsened, a trip to the local clinic resulted in the diagnosis of acute pancreatitis. Patterson was medevaced to Germany, where the pseudocyst was discovered—about the size of a football and full of murky brown liquid, indicative of a microbial infection. A sample was cultured, and the results were even more worrying: A. baumannii.

For Strathdee, the implications of the test results were not immediately apparent. An epidemiologist rather than a medical doctor, she recalled studying A. baumannii during her undergraduate microbiology training decades previously. Back then, she says, it was seen as a “really wimpy organism.” But with antimicrobial resistance on the rise, A. baumannii has evolved into a much more dangerous threat. In the US, it has gained the nickname “Iraqibacter” because of its prevalence among wounded soldiers who have picked up infections while serving in Iraq and other Middle Eastern countries. The reason it is such an urgent threat is because it is particularly adept at gaining resistance via multiple mechanisms—including through plasmids, DNA molecules that bacteria pass between one another—meaning many infections are multidrug-resistant or even pandrug-resistant. “I consider it something of a bacterial kleptomaniac,” Strathdee says. “It’s really great at stealing antimicrobial resistance genes from other bacteria and the environment.”

An antibiotic sensitivity test revealed that Patterson’s infection was indeed highly drug-resistant. Patterson was ultimately medevaced back to San Diego, where he took up residence in the intensive care unit. In one sense, Strathdee and Patterson had everything on their side: They were back on home turf, and the leading experts treating Patterson’s infection were not just colleagues but friends. Robert “Chip” Schooley, head of infectious diseases at UCSD, had been offering advice from the onset of Patterson’s illness, first over the phone and then in person on their return. Yet with the infection becoming resistant to all antibiotics, there was not much to be optimistic about. The pseudocyst was still there, and Patterson was now so frail that surgery was not an option; without any drugs in their arsenal, there was too great a risk that the infection could get into the bloodstream.

Over the course of several months, he kept getting sicker. One of the drains placed in his abdomen to remove infected fluid slipped, and the bacteria spread to his bloodstream, causing him to go into septic shock. After that, the bacteria were everywhere; he was fully colonized. His organs began to fail and he was in a coma. Strathdee could barely believe it: Not so long ago he’d been climbing into pyramids and jumping onto boats, and now he was fighting for his life. “I’m an infectious disease epidemiologist, so it was really like God’s cruel joke,” she says.

With antibiotics offering no solution, Strathdee resolved to leave no stone unturned in trying to find a cure for her husband. “I did what anybody would do,” she says. “I hit the internet.”

It was while browsing results from the biomedical search engine PubMed that Strathdee came across an unconventional idea: bacteriophages. A bacteriophage (often just known as a phage) is a type of virus that infects bacteria but doesn’t infect human cells. Once a phage has infected a bacterial cell, it effectively hijacks the cell’s mechanisms to turn it into a phage-producing machine. The resulting phages eventually burst out of the cell, destroying it, in an action called lysis.

It’s an attractively simple idea: Use a virus to infect the bacteria that are infecting a person. And it’s by no means new. Bacteriophages were discovered in the early 20th century and were even used to treat bacterial infections in the 1920s and 1930s, especially in the former USSR. But with the discovery of antibiotics, bacteriophage research became largely forgotten, at least in the West. Antibiotics were so good at treating bacterial infections, and the early research around phages was not enough to convince many researchers to pursue them as a potential therapy. There was perhaps an element of geopolitical stigma that put off Western researchers, too: Phages were still being used in the USSR, particularly in Georgia, where the Eliava Institute, an influential center for bacteriophage therapy, was opened in 1923.

Strathdee found a paper referencing phage therapy in relation to A. baumannii, but she couldn’t find any record of it being used in humans. Nevertheless, she decided it had to be worth a shot.

One of the difficulties of phage therapy is that you need to match the right phage with the right microbe. Phages are found in the same places as the bacteria they feed on: in the environment and inside our own bodies. To find ones that might be effective against particularly nasty bugs, you need to look where you might also find those particularly nasty bugs—like in a festering swamp, or a sewage system. But phages can be picky: The team treating Patterson would not just need to find phages that worked against A. baumannii in general but ones that worked against the exact bacteria taken from his sample—his “bacterial isolate.” And one phage wouldn’t be enough; as with antibiotics, bacteria can evolve to defend themselves against phages, so it would be more effective to use a cocktail of different phages attacking from multiple angles. “If you only have one phage, you’re giving the bacteria a leg up to develop resistance to the phage,” Strathdee explains. Thus began a search for laboratories with phage libraries that might have one active against Patterson’s infection.

Testing a phage is quite straightforward in principle. First, you take a sample of the bacteria from the infected person and grow it in the lab. Researchers then use something called a plaque assay: They take a Petri dish of agar and spread the bacteria over it, then add small drops of different phage solutions and let the whole thing incubate. The bacteria grow, forming an opaque layer. But in some places, it may appear to have small holes, like a slice of Emmental cheese. Here, the bacteria have been killed, leaving a small clearing or “plaque”—and indicating that the phages placed on that spot have succeeded in infecting the bacteria. Researchers then test these promising phages further against the bacterial isolate.

With the assistance of many helpers, the UCSD team managed to identify several phages that showed promise. The full story, which involves several laboratories around the world, assistance from the US Navy, and a race to get permission to apply the phages under compassionate use, is detailed in Strathdee and Patterson’s book, The Perfect Predator: A Scientist’s Race to Save Her Husband from a Deadly Superbug.

Just as difficult as finding the phages was then figuring out how to purify and administer them. Phages aren’t a standard therapy by any means; there was no handy guide. The team had little to go on in terms of dosage or how to apply them, but with Patterson by that point facing almost certain death without any intervention, they pushed ahead with the best regimen they could think of. “We injected a billion phages per dose every two hours in his body, and it was the scariest day of my life when we did that because it could have cured or killed him, nobody knew,” Strathdee says. (This dose was later reduced.)

A couple of days after treatment started, Patterson woke up from his coma. Against almost all expectations, the phage therapy had worked. “One of the doctors described it as a Hail Mary pass in the last quarter of the football game, where the quarterback is blindfolded, throwing the ball over 100 yards down the field and hoping that somebody will catch it,” Strathdee recalls. “And they did.”

Engineered Phages

Patterson is a member of a very small club of people who have been treated with bacteriophages in this way. But since his recovery, there has been more interest in using phages when patients are out of other options.

Graham Hatfull, a professor of biological sciences at the University of Pittsburgh in Pennsylvania who studies phages, says he had never really been involved in therapeutic applications. He’s not a physician or a clinician, but a “nerdy basic biologist.” He is interested in characterizing the genetic diversity of phages and works with thousands of students to isolate and catalog them, with a focus on phages that infect a group of bacteria called mycobacteria. The Mycobacterium genus includes Mycobacterium tuberculosis, which causes TB, as well as many other species that are important to human health.

But in 2017 Hatfull was contacted by James Soothill, a consultant microbiologist at Great Ormond Street Hospital in London, about a patient who was in a bad condition. The patient was a 15-year-old girl with cystic fibrosis who had been fighting an infection caused by drug-resistant Mycobacterium abscessus, which got worse after she had a double lung transplant (likely aided by the immunosuppressive medication needed to support the transplant). The wound from the transplant turned red and infected, and her body was covered in infected sores and nodules. Standard treatments weren’t working.

Prompted by the girl’s mother, Soothill was considering the idea of phages. Might Hatfull have something in his catalog of phages that could work against this patient’s M. abscessus?

Hatfull and his team tested the girl’s isolate against their collection and came up with a few potential matches—“but not very many, and we had to look really hard to find them amongst our collection,” he says. There’s another step to finding effective phages, however. For phages to kill bacteria, they need to be “lytic,” causing lysis of the cell by rupturing the cell membrane. But some phages, known as temperate phages, don’t always do this. They may kill bacterial cells most of the time, but sometimes they are instead “lysogenic,” which means they enter the bacterial cell but then become incorporated within it, allowing the bacteria to survive. “A phage that only kills 90 percent of the time isn’t going to be very good therapeutically, because 10 percent of quite a lot of bacteria is still a lot of bacteria,” Hatfull says.

Not only do you need to find the right phages for a particular bacterial infection, then—they must also be lytic ones. But many phages in Hatfull and his team’s collection are temperate, including two of the three they wanted to combine into a cocktail to treat this patient.

Their solution? Genome editing. They engineered the genomes of the phages such that they would always be lytic, by removing the genes needed for lysogeny. By doing this, Hatfull explains, “We’ve essentially converted a naturally occurring temperate phage into one that’s now lytic, and essentially moved it from the ‘can’t use’ category into the ‘potential use’ category.” He credits the basic biology his lab has been doing for the fact that they had such tools at their disposal; only by studying the genetics of phages did they have the knowledge and ability to do this engineering.

To decide on the details of how to administer the phages, Hatfull and his colleagues worked with Chip Schooley, who had been instrumental in Patterson’s treatment. Again, they had very little to go on; there is no real known optimal dose for intravenous phage therapy. They decided on a dose of a billion phage particles, twice a day. Giving such an experimental treatment, says Hatfull, is scary: “You spend a lot of time thinking about all the things that could go wrong, and then worrying about all the things that [you’re] not smart enough to think about.”

The treatment, as Hatfull and colleagues reported in Nature Medicine, was well tolerated, and the girl’s condition improved. It took a few weeks, but there was a reduction in bacterial load, the wound from her lung transplant closed, and her skin cleared up. Since this experience, Hatfull has been approached by many physicians—he estimates more than 200—who are interested in exploring phage therapy for their patients. But at the moment, in the US at least, phage therapy is still very experimental, permitted only on a case-by-case basis when there is no alternative.

For his part, Hatfull says he remains skeptical about whether phages will ever become a common therapy. In their paper on the M. abscessus case, the researchers noted that the patient’s condition might have improved anyway—it’s hard to draw solid conclusions from a one-off attempt. Clinical trials will be needed to see if phages could have widespread application.

One particular challenge with using phages on a larger scale is their specificity—the fact that they need to be tailored to a particular bacterial isolate rather than just a species of bacteria. This, Hatfull says, is “the critical factor that has complicated the advancement of phage therapy in the big picture.” Tailoring a treatment to an individual is expensive and time-consuming, and would make it difficult to adopt phage therapy as a straightforward alternative to antibiotics.

Perhaps, Hatfull suggests, phages could be a boutique treatment for certain infections where patients have little other recourse. Or they could be useful as an adjunct to antibiotics to treat specific infections if clinical trials show that combining the two therapies leads to better results. A future approach to phage therapy could be to design and make them synthetically, engineering them to be maximally effective. This could potentially help with the problem of specificity: If you could engineer a phage so that it works against more bacterial strains, maybe it would be possible to deploy it more broadly.

All of this is a long way off—there are regulatory and commercial hurdles, as well as scientific ones to overcome—but research groups and companies are starting to study phage therapy with renewed interest. Strathdee is now codirector of UCSD’s Center for Innovative Phage Applications and Therapeutics, which she founded with Chip Schooley in 2018 and which treats patients with phages on a case-by-case basis, according to the US Food and Drug Administration’s compassionate use program.

She also sees phages as a potential adjunct to, rather than replacement for, antibiotics. In her husband’s case, the bacteria mutated to stop the phages from working but in doing so made themselves more vulnerable for one of the antibiotics to attack. “So that kind of synergy where phages and antibiotics can be used together can be very powerful,” she says.

She hopes that phage therapy will allow us to use fewer antibiotics—crucial for keeping resistance at bay. As well as being used in medicine, perhaps they could find applications in veterinary care, agriculture, or aquaculture. It’s early days. But based on her experience, she is keen to act as an advocate for phage therapy. She recognizes that she and Patterson were incredibly privileged to have access to the resources they did. “The majority of people dying from superbug infections are in low-resource settings that don’t have access,” she says.

Vicki Turk is the author of Superbugs: How to Prevent the Next Global Health Threat. Find out more and order your copy of the book.

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Viruses to Fight Superbugs? Scientists Are Working on It

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The glossy leaves and branching roots of mangroves are downright eye-catching, and now a study finds that the moon plays a special role in the vigor of these trees.

Long-term tidal cycles set in motion by the moon drive, in large part, the expansion and contraction of mangrove forests in Australia, researchers report in the Sept. 16 Science Advances. This discovery is key to predicting when stands of mangroves, which are good at sequestering carbon and could help fight climate change, are most likely to proliferate (SN: 11/18/21). Such knowledge could inform efforts to protect and restore the forests.

Mangroves are coastal trees that provide habitat for fish and buffer against erosion (SN: 9/14/22). But in some places, the forests face a range of threats, including coastal development, pollution and land clearing for agriculture. To get a bird’s-eye view of these forests, Neil Saintilan, an environmental scientist at Macquarie University in Sydney, and his colleagues turned to satellite imagery. Using NASA and U.S. Geological Survey Landsat data from 1987 to 2020, the researchers calculated how the size and density of mangrove forests across Australia changed over time.

After accounting for persistent increases in these trees’ growth — probably due to rising carbon dioxide levels, higher sea levels and increasing air temperatures — Saintilan and his colleagues noticed a curious pattern. Mangrove forests tended to expand and contract in both extent and canopy cover in a predictable manner. “I saw this 18-year oscillation,” Saintilan says.

That regularity got the researchers thinking about the moon. Earth’s nearest celestial neighbor has long been known to help drive the tides, which deliver water and necessary nutrients to mangroves. A rhythm called the lunar nodal cycle could explain the mangroves’ growth pattern, the team hypothesized.

Over the course of 18.6 years, the plane of the moon’s orbit around Earth slowly tips. When the moon’s orbit is the least tilted relative to our planet’s equator, semidiurnal tides — which consist of two high and two low tides each day — tend to have a larger range. That means that in areas that experience semidiurnal tides, higher high tides and lower low tides are generally more likely. The effect is caused by the angle at which the moon tugs gravitationally on the Earth.  

Saintilan and his colleagues found that mangrove forests experiencing semidiurnal tides tended to be larger and denser precisely when higher high tides were expected based on the moon’s orbit. The effect even seemed to outweigh other climatic drivers of mangrove growth, such as El Niño conditions.

Other regions with mangroves, such as Vietnam and Indonesia, probably experience the same long-term trends, the team suggests.

Having access to data stretching back decades was key to this discovery, Saintilan says. “We’ve never really picked up before some of these longer-term drivers of vegetation dynamics.”

It’s important to recognize this effect on mangrove populations, says Octavio Aburto-Oropeza, a marine ecologist at the Scripps Institution of Oceanography in La Jolla, Calif., who was not involved in the research.

Scientists now know when some mangroves are particularly likely to flourish and should make an extra effort at those times to promote the growth of these carbon-sequestering trees, Aburto-Oropeza says. That might look like added limitations on human activity nearby that could harm the forests, he says. “We should be more proactive.”

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The ABRACADABRA (ABRA) and Reading and Understanding in Key Stage 1 (RUKS) program involved more than 4,000 Year 1 pupils (age 5–6) from 157 schools across the West Midlands, East Midlands, Newcastle, Teesside and Manchester.

Schools took part in a 20-week trial in which two versions of the ABRA-based RUKS program were tested: an ICT-based model and a paper-based model, while some participating schools were assigned to a control group and carried on their usual approach to teaching literacy.

The content for both forms of the program came from the ABRACADABRA software developed by a team at Concordia and McGill University in Canada. The resources for the paper-based version were adapted by a team from Nottingham Trent University (NTU) and Coventry University, who also developed the 20-week RUKS program for both versions using the ABRA content.

Using a train-the-trainer model, the team trained teachers and teaching assistants to deliver four reading-based sessions per week to small groups of four to five pupils, and then monitored the delivery.

These fifteen-minute sessions consisted of decoding (including phonics), fluency and comprehension activities drawn from age-appropriate texts.

An independent evaluation by the York Trials Unit, University of York, and Durham University—released in an EEF report—found that children who received either version of the program made some additional progress on measures of decoding and phonics compared with pupils in the control group.

However, of the two models of delivery, the paper-based approach proved to be the most effective—children who received this version made up to two months' additional progress in reading.

The program was well-received by delivery schools, with staff reporting that they felt well supported to implement the program.

Both versions of the ABRA-based RUKS program first showed promise when tested in a smaller scale trial completed in January 2015, involving 1884 pupils from 60 English schools.

Janet Vousden, principal investigator on the project and senior lecturer in Psychology at NTU's School of Social Sciences, said, "It is very encouraging to see the results of this trial. They suggest that the program can be scaled up as a train-the-trainer model with similar positive outcomes for children."

Professor Becky Francis, Chief Executive of the Education Endowment Foundation, said, "We have so much to gain from education research and rigorously examining the impact of teaching and learning programs.

"These findings are a prime example—offering practitioners a tried and tested option to consider when looking to develop their approach to reading provision for Key Stage 1 pupils.

"However, it is of the utmost importance that educators have the means to implement evidence-informed programs and maximize the impact of their practice.

"As school energy and food costs increase, it is vital that they are not forced to direct resources away from the things which the evidence shows are likely to make the biggest difference."

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Hints are mounting that at least part of the problem lies with a principle at the center of quantum mechanics, an assumption about how the world works that seems so obvious it’s barely worth stating, much less questioning.

Unitarity, as the principle is called, says that something always happens. When particles interact, the probability of all possible outcomes must sum to 100%. Unitarity severely limits how atoms and subatomic particles might evolve from moment to moment. It also ensures that change is a two-way street: Any imaginable event at the quantum scale can be undone, at least on paper. These requirements have long guided physicists as they derive valid quantum formulas. “It’s a very restrictive condition, even though it might seem a little bit trivial at first glance,” said Yonatan Kahn, an assistant professor at the University of Illinois.

But what once seemed an essential scaffold may have become a stifling straitjacket preventing physicists from reconciling quantum mechanics and gravity. “Unitarity in quantum gravity is a very open question,” said Bianca Dittrich, a theorist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.

The main problem is that the universe is expanding. This expansion is well described by general relativity. But it means that the future of the cosmos looks totally different from its past, while unitarity demands a tidy symmetry between past and future on the quantum level. “There is a tension there, and it’s something quite puzzling if you think about it,” said Steve Giddings, a quantum gravity theorist at the University of California, Santa Barbara.

Concern over this conflict has been in the air for years. But recently, two quantum gravity theorists may have found a way to loosen unitarity’s buckles to better fit our growing cosmos. Andrew Strominger and Jordan Cotler of Harvard University argue that a more relaxed principle called isometry can accommodate an expanding universe while still satisfying the stringent requirements that first made unitary a guiding light.

“You don’t need unitarity,” said Strominger. “Unitarity is too strong of a condition.”

While many physicists are receptive to the isometry proposal — some have even come to similar conclusions independently — opinions vary as to whether the update is too radical or not radical enough.

A Fixed Sum

In everyday life, events can’t help but play out in a unitary way. A coin toss, for instance, has a 100% chance of coming up heads or tails.

But a century ago, the pioneers of quantum mechanics made a surprising discovery — one that elevated unitarity from common sense to a hallowed principle. The surprise was that, mathematically, the quantum world operates not by probabilities but by more complicated numbers known as amplitudes. An amplitude is essentially the degree to which a particle is in a certain state; it can be a positive, negative or imaginary number. To calculate the probability of actually observing a particle in a certain state, physicists square the amplitude, which gets rid of the imaginary and negative bits and produces a positive probability. Unitarity says the sum of these probabilities (really, the squares of all the amplitudes) must equal 1.

It’s this twist — the squaring of hidden amplitudes to calculate the outcomes we actually see — that gives unitarity teeth. As a particle’s state changes (as it flies through a magnetic field, say, or collides with another particle), its amplitudes change too. In working out how a particle is allowed to evolve or interact, physicists use the fact that amplitudes never change in a way that disrupts the fixed sum of their squares. In the 1920s, for instance, this unitarity requirement guided the British physicist Paul Dirac to discover an equation that implied the existence of antimatter. “I was not interested in considering any theory which would not fit in with my darling,” Dirac wrote, referring to unitarity.

Physicists keep probabilities and amplitudes in line by tracking how the quantum state of a particle moves around in Hilbert space — an abstract space representing all possible states available to the particle. The particle’s amplitudes correspond to its coordinates in Hilbert space, and physicists capture changes to the particle with mathematical objects called matrices, which transform its coordinates. Unitarity dictates that a physically allowed change must correspond to a special “unitary” matrix that rotates the particle’s state in Hilbert space without changing that the sum of the squares of its coordinates equals 1.

It’s a mathematical fact with philosophical consequences: If you know the specific unitary matrix corresponding to some change over time, any quantum state can be swiveled into the future or unswiveled into the past. It will always land on another viable state in the Hilbert space, which never grows or shrinks. “The past completely determines the future, and the future completely determines the past,” said Cotler. “It’s related to the statement that information is neither created nor destroyed.”

And yet, this bedrock assumption seems to conflict with the universe that surrounds us.

A Cosmic Clash

Galaxies are flying ever farther apart. While our expanding universe is a perfectly valid solution to the equations of general relativity, physicists have increasingly realized that its growth spells trouble for quantum mechanics, by presenting particles with an expanding smorgasbord of options for where to be and how to behave. As space grows, how can the Hilbert space of possibilities not grow with it? “It’s definitely true that there are more degrees of freedom in the universe now than in the early universe,” said Nima Arkani-Hamed, a theoretical physicist at the Institute for Advanced Study in Princeton, New Jersey.

“I’ve felt for many years [that] it was the elephant in the room,” said Strominger.

Giddings sharpens the issue with a paradoxical thought experiment set in a universe that’s both unitary and expanding. Imagine taking the current state of the universe, said Giddings, and adding “one innocuous photon” — perhaps lodged in newly created space halfway between here and the Andromeda galaxy. Unitarity insists that we must be able to calculate what this universe looked like in the past, unswiveling its quantum state as much as we wish.

But rewinding the state of the universe plus an extra photon creates a glitch. Going into the past, the universe gets smaller, and the wavelength of photons will shrink too. In our real universe, this isn’t a problem: A photon shrinks only until the moment of its creation through some subatomic process; the reversal of that process will make it disappear. But the extra photon wasn’t created by that special process, so instead of disappearing when you turn back time, its wavelength will eventually get impossibly small, concentrating its energy so greatly that the photon collapses into a black hole. This creates a paradox, absurdly implying that — in this fictional, expanding universe — microscopic black holes convert into photons. The thought experiment suggests that a naïve mashup of unitarity and cosmic expansion doesn’t work.

Dittrich thinks unitarity smells fishy on more general grounds. Quantum mechanics treats time as absolute, but general relativity messes with the ticking of clocks, complicating the notion of change from one moment to the next. “I personally never relied so much on unitarity,” she said.

The question is: What sort of alternative framework could accommodate both cosmic expansion and the rigid mathematics of quantum theory?

Unitarity 2.0

Last year, Strominger struck up a collaboration with Cotler, who splits his time between quantum gravity research and quantum information theory — the study of information stored in quantum states. The duo realized that there is a well-studied scheme in quantum information theory that resembles the expanding universe: quantum error correction, a scheme where a small message made from quantum states is redundantly encoded inside a bigger system. Perhaps, they thought, the contents of the young universe are similarly stitched into the modern cosmos’s swollen form.

“In hindsight, the obvious answer is this is exactly what people doing quantum encoding have been doing,” Strominger said.

In a paper earlier this year, the two homed in on a class of transformations that quantum error-correcting codes belong to, known as isometries. An isometric change resembles a unitary one with added flexibility.

Bianca Dittrich, of the Perimeter Institute for Theoretical Physics, struck upon isometry a decade ago while formulating a toy quantum theory of space-time.
Gabriela Secara/Perimeter Institute

Think of an electron that can occupy two possible locations. Its Hilbert space consists of all possible combinations of amplitudes in the two locations.

These possibilities can be imagined as the points on a circle — every point has some value in both the horizontal and vertical directions. Unitary changes rotate states around the circle but do not expand or shrink the set of possibilities.

To visualize an isometric change, though, let the universe of this electron swell just enough to allow a third position. The electron’s Hilbert space grows, but in a special way: It gains another dimension. The circle becomes a sphere, on which the particle’s quantum state can swivel around to accommodate mixtures of all three locations. The distance between any two states on the circle holds steady under the change — another requirement of unitarity. In short, the options increase, but without unphysical consequences.

“Working with isometries is sort of a generalization” of unitarity, said Giddings. “It keeps some of the essence.”

Our universe would have a Hilbert space with a huge number of dimensions that proliferate continuously as real space expands. As a simpler proof of concept, Strominger and Cotler studied the expansion of a toy universe consisting of a line ending in a receding mirror. They calculated the probability that the universe would grow from one length to another.

For such calculations, quantum practitioners often use the Schrödinger equation, which predicts how a quantum system evolves in time. But changes dictated by the Schrödinger equation are perfectly reversible; its “literal purpose in life is to enforce unitarity,” Arkani-Hamed said. So instead, Strominger and Cotler used an alternative version of quantum mechanics dreamed up by Richard Feynman, called the path integral. This method, which involves tallying up all the paths a quantum system can take from some starting point to an endpoint, has no trouble accommodating the creation of new states (which appear as branching paths leading to multiple endpoints). In the end, Strominger and Cotler’s path integral spit out a matrix encapsulating the growth of the toy cosmos, and it was indeed an isometric matrix rather than a unitary one.

“If you want to describe an expanding universe, the Schrödinger equation as it stands just won’t work,” Cotler said. “But in the Feynman formulation, it keeps on working on its own volition.” Cotler concludes that this alternative way of doing quantum mechanics based on isometry “will be more useful to us in understanding an expanding universe.”

A Mirage of Possibilities

Relaxing unitarity could resolve the glitches in the thought experiment that has troubled Giddings and others. It would do so through a conceptual change to how we think about the relationship between the past and the future, and which states of the universe are really possible.

To see why isometry solves the problem, Cotler describes a toy universe, one born in one of two possible initial states, 0 or 1 (a two-dimensional Hilbert space). He makes up an isometric rule to govern this universe’s expansion: At every successive moment, each 0 becomes 01, and each 1 becomes 10. If the universe starts at 0, its first three moments will see it grow as follows: 0 → 01 → 0110 → 01101001 (an 8D Hilbert space). If it starts at 1, it will become 10010110. The string captures everything about this universe — all its particles’ positions, for instance. A considerably longer string made from superpositions of 0s and 1s presumably describes the real universe.

At any given time, the toy universe has two possible states: one arising from 0 and another arising from 1. The initial one-digit configuration has been “encoded” in a larger, eight-digit state. That evolution resembles a unitary one, in that there are two possibilities at the beginning and two at the end. But the isometric evolution provides a more capable framework for describing the expanding universe. Crucially, it does so without creating the freedom to add, say, an extra photon between here and Andromeda, which would spell trouble when you turn back the clock. Imagine, for instance, that the universe is in the 01101001 state. Flip the first 0 to a 1 — representing a minor, local tweak, such as the extra photon — and you’ll get a state that looks fine on paper (11101001), with a seemingly valid set of coordinates in the larger Hilbert space. But knowing the specific isometric rule, you can see that such a state has no parent state. This imaginary universe could never have arisen.

“There are some configurations of the future that don’t correspond to anything in the past,” Cotler said. “There’s nothing in the past that would evolve into them.”

Giddings has proposed a similar principle for ruling out paradoxical states he encountered while studying black holes last year. He calls it “history matters,” and it holds that a given state of the universe is only physically possible if it can evolve backward without generating contradictions. “This has been kind of a lingering puzzle,” he said. Strominger and Cotler “are taking that puzzle and using it to try to motivate possibly a new way of thinking about things.”

Giddings thinks the approach deserves further development. So does Dittrich, who came to similar realizations about isometry a decade ago while attempting to formulate a toy quantum theory of space-time with her collaborator Philipp Höhn. One hope is that such work could eventually lead to the specific isometric rule that might govern our universe — a rather more complicated prescription than “0 goes to 01.” A true cosmological isometry, Cotler speculates, could be verified by calculating which specific patterns in the distribution of the matter in the sky are possible and which aren’t, and then testing those predictions against observational data. “If you look closer at it, you’ll find this but not this,” he said. “That could be really useful.”

 To Isometry and Beyond

While such experimental evidence could accrue in the future, in the near term, evidence for isometry is more likely to come from theoretical studies and thought experiments showing that it helps combine the malleability of space-time with the amplitudes of quantum theory.

One thought experiment where unitarity looks creaky involves black holes, intense concentrations of matter that warp space-time into a dead end. Stephen Hawking calculated in 1974 that black holes evaporate over time, erasing the quantum state of anything that fell in — a seemingly blatant unitarity violation known as the black hole information paradox. If black holes have Hilbert spaces that mature isometrically, as Cotler and Strominger hypothesize, physicists may face a somewhat different puzzle than they thought. “I don’t think there can be a solution that doesn’t take this into account,” Strominger said.

Another prize would be a detailed quantum theory that described not just how the cosmos grows, but where everything came from in the first place. “We have no universe, and all of a sudden we have a universe,” Arkani-Hamed said. “What the hell kind of unitary evolution is that?”

For his part, however, Arkani-Hamed doubts that swapping in isometry for unitarity goes far enough. He is one of the leaders of a research program that is trying to break free of many fundamental assumptions in quantum theory and general relativity, not just unitarity.

Whatever theory comes next, he suspects, will take a completely novel form, just as quantum mechanics was a clean break from Isaac Newton’s laws of motion. As an illustrative example of what a new form might look like, he points to a research program stemming from a 2014 discovery he made together with Jaroslav Trnka, his student at the time. They showed that when certain particles collide, the amplitude of each possible outcome equals the volume of a geometric object, dubbed the amplituhedron. Calculating the object’s volume is much easier than using standard methods for computing the amplitudes, which laboriously reconstruct all the ways a particle collision might play out, moment by moment.

Intriguingly, while the amplituhedron gives answers that obey unitarity, the principle isn’t used to construct the shape itself. Neither are any assumptions about how particles move in space and time. The success of this purely geometric formulation of particle physics raises the possibility of a fresh perspective on reality, one free from the cherished principles that currently conflict. Researchers have gradually been generalizing the approach to explore related geometric shapes pertaining to different particles and quantum theories.

“[It] may be a different way to organize unitarity,” Cotler said, “and perhaps it has the seeds to transcend it.”

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