NASA’s new powerful space observatory, the James Webb Space Telescope, got pelted by a larger than expected micrometeoroid at the end of May, causing some detectable damage to one of the spacecraft’s 18 primary mirror segments. The impact means that the mission team will have to correct for the distortion created by the strike, but NASA says that the telescope is “still performing at a level that exceeds all mission requirements.”

NASA’s James Webb Space Telescope, or JWST, is the agency’s incredibly powerful next-generation space telescope, designed to look into the farthest reaches of the Universe and see back in time to the stars and galaxies that formed just after the Big Bang. It cost NASA nearly $10 billion to build and more than two decades to complete. But, on Christmas Day 2021, the telescope finally launched to space, where it underwent an extremely complex unfolding process before reaching its final destination roughly 1 million miles from Earth.

Since its launch, JWST has already been hit by at least four different micrometeoroids, according to a NASA blog post, but all of those were small and about the size of what NASA expected the observatory to encounter. A micrometeoroid is typically a small fragment of an asteroid, usually smaller than a grain of sand. The one that hit JWST in May, however, was larger than what the agency had prepared for, though the agency didn’t specify its exact size. NASA admits that the strike, which occurred between May 23rd and May 25th, has caused a “marginally detectable effect in the data” and that engineers are continuing to analyze the effects of the impact.

NASA expected JWST to get hit by tiny space particles during its lifetime; fast-moving specks of space rock are just an inescapable feature of the deep space environment. In fact, NASA designed the telescope’s gold-coated mirrors to withstand strikes by tiny space debris over time. The space agency also did a combination of simulations and ground testing with mirror samples to determine how to best strengthen the mirrors to withstand micrometeoroid impacts. However, NASA says that the models they used for these simulations didn’t have a micrometeoroid this large, and it was “beyond what the team could have tested on the ground.”

Still, this doesn’t come as a total surprise. “We always knew that Webb would have to weather the space environment, which includes harsh ultraviolet light and charged particles from the Sun, cosmic rays from exotic sources in the galaxy, and occasional strikes by micrometeoroids within our solar system,” Paul Geithner, technical deputy project manager at NASA’s Goddard Space Flight Center, said in a statement.

The primary mirror of JWST undergoing testing on Earth Image: NASA

Engineers do have the capability to also maneuver JWST’s mirror and instruments away from showers of space debris, if NASA can see them coming. The problem, though, was that this micrometeoroid was not part of a shower, so NASA considers it an “unavoidable chance event.” Still, the agency is forming an engineering team to come up with ways to potentially avoid or lessen the effects of micrometeoroid strikes of this size. And since JWST is so sensitive, the telescope will also help NASA get a better understanding of just how many micrometeoroids there are in the deep space environment.

Despite the strike, NASA remained optimistic in its post about JWST’s future. “Webb’s beginning-of-life performance is still well above expectations, and the observatory is fully capable of performing the science it was designed to achieve,” according to the blog. Engineers can also adjust the impacted mirror to help cancel out the data distortion. The mission team has done this already and will continue to tinker with the mirror over time to get the best results. It’s a process that will be ongoing throughout JWST’s planned five to 10 years of life as new observations are made and events unfold. At the same time, NASA warns that the engineers will not be able to completely cancel out the impact of the strike.

NASA engineers had to build JWST to be incredibly robust since the telescope is on its own out in space. Unlike its predecessor, the Hubble Space Telescope, which is currently in orbit around Earth, JWST was not designed to be serviceable. That means if something significant breaks on the spacecraft, engineers will have to troubleshoot a way to fix it from the ground. There’s no capability at the moment to send humans or a robotic spacecraft to give JWST a tune-up. That means JWST will have to live with its slightly damaged mirror until the end of its mission, and NASA expects the spacecraft to get hit by even more debris over time.

In the meantime, the strike doesn’t appear to be impacting JWST’s schedule. In fact, the news of this micrometeoroid comes just a month before a huge milestone for the mission. After spending the last few months finely calibrating JWST’s instruments and delicately aligning the spacecraft’s mirrors, the mission team is set to unveil the first full-color images from JWST on July 12th. NASA won’t say what the images will be, but they should be spectacular.

NASA’s new powerful space telescope gets hit by larger than expected micrometeoroid

This plasma ignition system can increase engine efficiency by 20%

British researchers have developed a biodegradable gel to repair damage caused by a heart attack in a breakthrough that could improve the health of millions of survivors worldwide.

There are more than 100,000 hospital admissions every year due to heart attacks in the UK alone – one every five minutes. Medical advances mean more people than ever before survive, with 1.4 million Britons alive today after experiencing a heart attack. But hearts have a very limited ability to regenerate, meaning survivors are left at risk of heart failure and other health problems.

Now after years of efforts searching for solutions to help the heart repair itself, researchers at the University of Manchester have created a gel that can be injected directly into the beating heart – effectively working as a scaffold to help injected cells grow new tissue.

Until now, when cells have been injected into the heart to reduce the risk of heart failure, only 1% have stayed in place and survived. But the gel can hold them in place as they graft on to the heart.

“While it’s still early days, the potential this new technology has in helping to repair failing hearts after a heart attack is huge,” said Katharine King, who led the research backed by the British Heart Foundation (BHF). “We’re confident that this gel will be an effective option for future cell-based therapies to help the damaged heart to regenerate.

To prove the technology could work, researchers showed the gel can support growth of normal heart muscle tissue. When they added human cells reprogrammed to become heart muscle cells into the gel, they were able to grow in a dish for three weeks and the cells started to spontaneously beat.

Echocardiograms (ultrasounds of the heart) and electrocardiograms (ECGs, which measure the electrical activity of the heart) on mice confirmed the safety of the gel. To gain more knowledge, researchers will test the gel after mice have a heart attack to show they develop new muscle tissue.

The study is being presented at the British Cardiovascular Society conference in Manchester.

Prof James Leiper, an associate medical director at the BHF, said: “We’ve come so far in our ability to treat heart attacks and today more people than ever survive. However, this also means that more people are surviving with damaged hearts and are at risk of developing heart failure.

“This new injectable technology harnesses the natural properties of peptides to potentially solve one of the problems that has hindered this type of therapy for years. If the benefits are replicated in further research and then in patients, these gels could become a significant component of future treatments to repair the damage caused by heart attacks.”

Separate research being presented at the same conference found that obesity can drive hearts to fail and weaken their structure.

The largest study of its kind on 490,000 people found that those with a higher body mass index (BMI) and waist-to-hip ratio had about a 30% increased risk of heart failure. This risk occurred regardless of other risks for heart failure such as diabetes, high blood pressure and high cholesterol.

Dr Zahra Raisi-Estabragh, from Queen Mary University of London, who supervised the study, said: “We already know that obesity increases the risk of heart and circulatory diseases that can go on to cause heart failure. But now we have revealed that obesity itself could be a driver of hearts starting to fail.”

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Most people see Antarctica as a pristine, relatively untouched place, but a new study published today (8 June) has revealed the presence of microplastics—plastic pieces much smaller than a grain of rice—in freshly fallen Antarctic snow for the first time.

These findings, "First evidence of microplastics in Antarctic snow" published in the scientific journal The Cryosphere, bring light to a serious threat to the Antarctic. Research has found that microplastics have negative impacts on environmental health (limiting growth, reproduction, and general biological functions in organisms, as well as negative implications for humans). On a wider scale, the presence of microplastic particles in the air has the potential to influence the climate by accelerating melting of snow and ice.

University of Canterbury Ph.D. student Alex Aves collected snow samples from the Ross Ice Shelf in Antarctica in late 2019 as part of Gateway Antarctica's Postgraduate Certificate of Antarctic Studies. (Gateway Antarctica is the Centre for Antarctic Studies and Research at the University of Canterbury.) At the time, there had been few studies investigating the presence of microplastics in the air, and it was unknown how widespread this problem was.

"When Alex traveled to Antarctica in 2019, we were optimistic that she wouldn't find any microplastics in such a pristine and remote location," Associate Professor in Environmental Physics Dr. Laura Revell says. In addition to more remote sites, "we asked her to collect snow off the Scott Base and McMurdo Station roadways, so she'd have at least some microplastics to study."

Once back in the lab, it quickly became obvious there were plastic particles in every sample from the remote sites on the Ross Ice Shelf too, and that the findings would be of global significance.

Aves, who recently graduated with a Master of Antarctic Studies degree with Distinction, says she was shocked by her findings.

"It's incredibly sad but finding microplastics in fresh Antarctic snow highlights the extent of plastic pollution into even the most remote regions of the world," she says. "We collected snow samples from 19 sites across the Ross Island region of Antarctica and found microplastics in all of these."

"Looking back now, I'm not at all surprised," Associate Professor Revell says. "From the studies published in the last few years we've learned that everywhere we look for airborne microplastics, we find them."

Aves analyzed snow samples using a chemical analysis technique (micro-Fourier transform infrared spectroscopy) to identify the type of plastic particles present. The plastic particles were also looked at under a microscope to identify their color, size and shape—all important observational information for future work.

The paper found an average of 29 microplastic particles per liter of melted snow, which is higher than marine concentrations reported previously from the surrounding Ross Sea and in Antarctic sea ice.

Immediately next to the scientific bases on Ross Island, Scott Base, and McMurdo Station, the largest station in Antarctica, the density of microplastics was nearly 3-times higher, with similar concentrations to those found in Italian glacier debris. There were 13 different types of plastic found, with the most common being PET, commonly used to make soft drink bottles and clothing.

The possible sources of microplastics were examined. "Atmospheric modeling suggested microplastics may have traveled thousands of kilometers through the air, however it is equally likely the presence of humans in Antarctica has established a microplastic 'footprint,'" the researchers say.

Antarctica New Zealand environmental advisor Natasha Gardiner has described this UC research as "of huge value."

"Alex and her colleagues' research enables Antarctic Treaty Parties to make evidence-based decisions regarding the urgent need to reduce plastic pollution in the future. It improves our understanding of the extent of plastic pollution near to Scott Base and where it's coming from. We can use this information to reduce plastic pollution at its source and inform our broader environmental management practices," she says.

"Importantly, this research project also informs policy at the international level, and we have submitted a paper on the findings to the forthcoming Antarctic Treaty Consultative Meeting."

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Today, the Redmond tech giant has announced that it is significantly downsizing its operations in Russia, with over 400 employees being affected. In a statement to Bloomberg, Microsoft noted that:

As a result of the changes to the economic outlook and the impact on our business in Russia, we have made the decision to significantly scale down our operations in Russia. We will continue to fulfill our existing contractual obligations with Russian customers while the suspension of new sales remains in effect.

We are working closely with impacted employees to ensure they are treated with respect and have our full support during this difficult time.

Given that Microsoft already halted new sales of services and products in Russia in March, it's natural - but unfortunate for affected employees - that the company is downscaling its operations in the country in terms of headcount too. While existing contractual obligations will be honored, its clear that the firm does not want to invest its efforts in Russia until political and economic stability is reached.

Source: Bloomberg

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FDA advisors overwhelmingly endorse Novavax COVID-19 vaccine

NASA and SpaceX stand down on Dragon launch to study hydrazine issue

Headaches can be painful and disabling.

Some people get headaches due to stress. Other headaches result from overusing medications like painkillers.

Researchers reviewed 357 articles

A research team has arrived at the findings through a large-scale review of several hundred publications. The review highlights just how common headache struggles are.

"Headaches are a real and extremely frequent disorder. The condition is widespread in countries everywhere—although there can be differences," says Lars Jacob Stovner, a professor at NTNU.

Stovner and his colleagues identified 357 articles published between 1961 and the end of 2020.

The articles covered different countries and time periods, and varied in their analytical approaches. Nevertheless, the research team was able to analyze the data to explore the prevalence of headache disorders around the world.

The results published in The Journal of Headache and Pain indicate that more than half of the world's population has an active headache disorder.

Confirms previous findings on headaches

Headache prevalence is described as having experienced some type of headache over the past year. Further analyses revealed that just under 16 percent of people around the world had a headache on any given day.

While many of the studies did not report specific headache types, those that did suggest that approximately seven percent of the global population experience migraines on any given day, and almost nine percent experience a tension headache.

The review also highlighted that the incidence of headaches varied by gender, with 17 percent of women suffering from migraines in a given year, compared with 8.6 percent of men.

Getting headaches for 15 or more days a month was also much more common in women.

Stovner says the general findings are consistent with previous estimates of the incidence of headaches, including the Global Burden of Disease Study.

Working age adults are hardest hit

Stovner and his colleagues have previously found that migraines are the leading cause of disability for people under the age of 50.

"A lot of other bodily pains increase as we approach retirement age. Migraines and headaches are most prevalent in the most active years of our life," says Stovner, who also works with the Global Campaign against Headache.

He adds that headaches can have multiple causes—from an individual's genetics to stress, sleep problems and overuse of medication.

Stovner emphasizes that many options exist for preventing headache disorders or treating them when they occur.

"Headache woes are something the health service needs to take seriously. We have to inform the public, decision-makers and health services about this huge public health problem. We need to put a good system into place that gives everyone with these ailments access to good treatment, as well as to knowledge that enables them to reduce the negative impact as much as possible," he says.

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Barichivich is well acquainted with the tree. He grew up in and around the park, as both his parents worked as park rangers there. It was only recently that he began a serious study of the tree. His work involved taking a non-destructive core sample to count the tree's growth rings—the gold standard for determining a tree's age. Unfortunately, the drilling device was too short to penetrate all the way to the center of the tree. Thus, he only got a partial count.

Undaunted, he collected core samples from other, younger trees of the same type growing in the vicinity. He then used statistical modeling to make a guess at the tree's age. Information for the modeling came from core data from the Alerce Milenario and from the other core samples, along with environmental data. The model was then used to estimate the number of rings that likely formed in the inner parts of the core that were missing. The model suggests that the tree is likely 5,484 years old, which breaks the record for oldest tree by over 600 years. The old record was held by a bristlecone pine growing in California—testing had shown it to be 4,853 years old.

Barichivich refers to the tree as Gran Abuelo and plans to continue studying its features. He acknowledges that more work is required to confirm its age, including getting a full core sample. In the meantime, he has been pressuring the government to put stronger protections in place for the tree, suggesting it represents a truly historical specimen.

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The dangerous consequences of prolonged inactivity in humans are widely known. Too much sitting leads to an increased risk of heart disease, Type 2 diabetes, and other chronic illnesses, including depression. To offset the severe side effects of a sedentary lifestyle, doctors recommend adults complete at least 150 minutes of moderate to vigorous aerobic exercise a week.

However, a new study from San Diego State University, published in JAMA Network Open, found that doing lighter intensity daily activities such as household chores can significantly reduce the risk of stroke.

"Light-intensity physical activity can include vacuuming, sweeping the floor, washing the car, leisure strolling, stretching, or playing catch," said Steven Hooker, dean of SDSU's College of Health and Human Services and lead researcher of the cohort study.

"We observed that both physical activity and being sedentary independently impacted stroke risk. Our research demonstrates that strategies for stroke prevention should focus on both."

Hooker and his research colleagues measured both the amount of time participants were sedentary and the duration and intensity of physical activity in 7,600 adults ages 45 and older and then compared the data to the incidence of strokes in participants over seven years.

They found those who were sedentary for 13 hours or more a day had a 44% increased risk of having a stroke.

"The findings are more potent because the activity and sedentary behaviors were measured with an accelerometer, providing substantially more accurate data than previous studies that relied on self-reported measures," said Hooker, a former coordinator of the California Active Aging Project with a history of research into healthy lifestyles for older adults.

Study participants wore a hip-mounted accelerometer, a sensitive motion detector that precisely recorded physical activity and the duration of sitting and inactivity.

Even though smartphones and smartwatches valiantly attempt to motivate Americans to move more, a shocking percentage of adults don't exercise enough. The CDC reports only 23% of U.S. adults meet the weekly recommendations for aerobic and muscle-strengthening activity.

But, if 10,0000 steps a day or closing an exercise ring on your watch seem out of reach, Hooker said getting up and doing even ten minutes of light to moderate physical activity a few times throughout the day is an effective strategy in reducing the likelihood of having a stroke.

"For overall heart and brain health, move more within your capacity, and sit less," said Hooker.

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The Mars Ingenuity helicopter is in need of a patch to work around a failed sensor before another flight can be attempted.

The helicopter's inclinometer failed during a recommissioning effort ahead of the 29th flight. The sensor is critical as it will reposition the craft nearer to the Perseverance rover for communication purposes.

Although not required during flight, the inclinometer (which consists of two accelerometers) is used to measure gravity prior to spin-up and takeoff. "The direction of the sensed gravity is used to determine how Ingenuity is oriented relative to the downward direction," said Håvard Grip, Ingenuity Mars Helicopter chief pilot.

Despite the experimental nature of Ingenuity, the helicopter has redundancies. It has accelerometers which, while not designed for sensing static orientation, can be used to estimate the initial attitude of the vehicle.

"We believe," wrote Grip, "an IMU-based initial attitude estimate will allow us to take off safely and thus provides an acceptable fallback that will allow Ingenuity to resume flying."

IMU stands for inertial measurement unit.

However, a patch is needed. Engineers anticipated this and the code is waiting for its time to shine. "The patch," according to Grip, "inserts a small code snippet into the software running on Ingenuity's flight computer, intercepting incoming garbage packets from the inclinometer and injecting replacement packets constructed from IMU data."

The process of uplinking it to the helicopter is already under way and time is of the essence. Ingenuity has endured far beyond expectations, but with shorter days and dropping power levels engineers are having to work around the helicopter shutting down overnight and exposing its electronics to lower temperatures than they were designed to survive.

The uplinking of the software patch is expected to be completed within the next few sols and commissioning shortly after. Once done, Ingenuity will be able to take to the skies once more for that crucial repositioning flight. ®

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Up to 30% of people with depression don't respond to treatment with antidepressants. This may be down to differences in biology between patients and the fact that it often takes a long time to respond to the drugs – with some people giving up after a while. So there is an urgent need to expand the repertoire of drugs available to people with depression.

In recent years, attention has turned to psychedelics such as psilocybin, the active compound in "magic mushrooms". Despite a number of clinical trials showing that psilocybin can rapidly treat depression, including for cancer-related anxiety and depression, little is known about how psilocybin actually works to relieve depression in the brain.

Now two recent studies, published in The New England Journal of Medicine and Nature Medicine, have shed some light on this mysterious process.

Psilocybin is a hallucinogen that changes the brain's response to a chemical called serotonin. When broken down by the liver (into "psilocin"), it causes an altered state of consciousness and perception in users.

Previous studies, using functional MRI (fMRI) brain scanning, have shown that psilocybin seems to reduce activity in the medial prefrontal cortex, an area of the brain that helps regulate a number of cognitive functions, including attention, inhibitory control, habits and memory. The compound also decreases connections between this area and the posterior cingulate cortex, an area that may play a role in regulating memory and emotions.

An active connection between these two brain areas is normally a feature of the brain's "default mode network". This network is active when we rest and focus internally, perhaps reminiscing about the past, envisioning the future or thinking about ourselves or others. By reducing the activity of the network, psilocybin may well be removing the constraints of the internal "self" – with users reporting an "opened mind" with increased perception of the world around them.

Interestingly, rumination, a state of being "stuck" in negative thoughts, particularly about oneself, is a hallmark of depression. And we know that patients with higher levels of negative rumination tend to show increased activity of the default mode network compared with other networks at rest – literally becoming less responsive to the world around them. It remains to be seen, however, if the symptoms of depression cause this altered activity, or if those with a more active default mode network are more prone to depression.

The key to psilocybin's effectiveness might lie in how it changes our "default mode network" (Credit: Getty Images)

The most compelling evidence of how psilocybin works comes from a double-blind randomised controlled trial (the gold-standard of clinical studies) that compared a group of depressed people taking psilocybin with those taking the existing antidepressant drug escitalopram – something that's never been done before. The trial was further analysed using fMRI brain scans, and the results were compared with other fMRI findings from another recent clinical trial.

Just one day after the first dose of psilocybin, fMRI measures revealed an overall increase in connectivity between the brain's various networks, which are typically reduced in those with severe depression. The default mode network was simultaneously reduced, while connectivity between it and other networks was increased – backing up previous, smaller studies.

The dose increased connectivity more in some people than others. But the studies showed that the people who had the biggest boost in connection between networks also had the greatest improvement in their symptoms six months later.

The brains of people taking escitalopram, on the other hand, showed no change in connectivity between the default mode and other brain networks six weeks after treatment started. It is possible that escitalopram may bring about changes at a later time point. But the rapid onset of psilocybin's antidepressant effect means it may be ideal for people who don't respond to existing antidepressants.

The study proposes that the observed effect may be due to psilocybin having more concentrated action on receptors in the brain called "serotonergic 5-HT2A receptors" than escitalopram. These receptors are activated by serotonin and are active throughout network brain areas, including the default mode network. We already know that the level of binding by psilocybin to these receptors leads to psychedelic effects. Exactly how their activation leads to changes in network connectivity is still to be explored though.

The end of traditional antidepressants?

This does raise the question of whether altered activity of the brain's networks is required for treating depression. Many people taking traditional antidepressants still report an improvement in their symptoms without it. In fact, the study showed that, six weeks after commencing treatment, both groups reported improvement in their symptoms.

According to some depression rating scales, however, psilocybin had the greatest effect on overall mental wellbeing. And a greater proportion of patients treated with psilocybin showed a clinical response compared with those treated with escitalopram (70% versus 48%). More patients in the psilocybin group were also still in remission at six weeks (57% versus 28%). The fact that some patients still do not respond to psilocybin, or relapse after treatment, shows just how difficult it can be to treat depression.

What's more, mental health professionals supported both treatment groups during and after the trial. The success of psilocybin is heavily dependent on the environment in which it is taken. This means it is a bad idea to use it for self-medicating. Also, patients were carefully selected for psilocybin-assisted therapy based on their history to avoid the risk of psychosis and other adverse effects.

Regardless of the caveats, these studies are incredibly promising and move us closer to expanding the available treatment options for patients with depression. What's more, internalised negative thought processes are not specific to depression. In due course, other disorders, such as addiction or anxiety, may also benefit from psilocybin-assisted therapy.

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With BA.2.12.1 now dominant in US, experts eye new subvariants BA.4 and BA.5

The medication given, called dostarlimab and sold under the brand name Jemperli, is an immunotherapy drug used in the treatment of endometrial cancer, but this was the first clinical investigation of whether it was also effective against rectal cancer tumors.

The early results reported so far suggest it is surprisingly effective, with the research team saying the successful cancer remission seen in every trial patient may be unprecedented for a cancer drug intervention.

"I believe this is the first time this has happened in the history of cancer," medical oncologist Luis Diaz Jr. from Memorial Sloan Kettering Cancer Center (MSK), the senior author of a new paper reporting the results, told The New York Times.

It's worth noting that the positive results have only been seen in 12 patients so far (the trial is ongoing), all of whom had tumors with genetic mutations called mismatch repair deficiency (MMRd), seen in a subset of approximately 5–10 percent of rectal cancer patients.

Patients with such tumors tend to be less responsive to chemotherapy and radiation treatments, which increases the need for surgical removal of their tumors.

However, MMRd mutations can also make cancer cells more vulnerable to immune response, especially it's bolstered by an immunotherapy agent – in this case, a checkpoint inhibitor, which unleashes restrictions on immune cells so they can more effectively kill cancer cells.

"When those mutations accumulate in the tumor, they stimulate the immune system, which attacks the mutation-ridden cancer cells," Diaz says. "We thought, 'Let's try it before cancer metastasizes as a first line of treatment'."

Ordinarily, patients with these kinds of rectal tumors might expect to undergo chemotherapy and radiation therapy prior to surgical removal of the cancer. Unfortunately, for many patients this gamut of treatments comes with long-lasting consequences that can last the rest of their life.

"The standard treatment for rectal cancer with surgery, radiation, and chemotherapy can be particularly hard on people because of the location of the tumor," says MSK medical oncologist Andrea Cercek, the first author of the study.

"They can suffer life-altering bowel and bladder dysfunction, incontinence, infertility, sexual dysfunction, and more."

In an amazing turn of luck, the patients who enrolled in this trial have so far completely avoided both these procedures and their associated side effects.
In the phase 2 study, patients were given dostarlimab every three weeks for six months, with standard chemoradiotherapy and surgery set to follow if tumors returned. They didn't.

After six months of follow-up, all 12 patients in the trial showed a "clinical complete response", with no evidence of tumors to be seen via MRI scans, PET scans, endoscopy, and biopsy, among other tests.

"Dr. Cercek told me a team of doctors examined my tests," explains Sascha Roth, the first patient enrolled in the trial. "And since they couldn't find any signs of cancer, Dr. Cercek said there was no reason to make me endure radiation therapy."

It's worth nothing that the research – funded by numerous organizations, including the pharmaceutical company GlaxoSmithKline, which manufactures Jemperli – isn't over yet, and these are only preliminary results being reported so far.

At present, a total of 12 patients have completed the treatment and undergone at least six months of follow-up.

About three-quarters of patients so far have experienced mild or moderate side effects, including rash, itching, fatigue, and nausea – but none have so far seen a regrowth in cancer, with the median follow-up being at one year, and some patients, like Roth, being cancer-free for two years.

Ultimately, the trial is expected to include about 30 patients. When we have data on the whole group, we'll have a fuller picture of how safe and effective dostarlimab is in patients with rectal cancer, although much more study is yet needed in broader groups of patients.

Until such time, we need to treat the current results with both optimism and caution, says oncologist Hanna K. Sanoff from the University of North Carolina at Chapel Hill, who has written a commentary on the findings.

According to Sanoff, a clinical complete response to the treatment is not a surrogate for long-term cancer control, as even though checkpoint inhibitors like dostarlimab can have effects lasting years, cancer regrowth is generally expected to still occur in a minority of patients where tumors are managed non-operatively, let alone with an experimental treatment like this.

"Very little is known about the duration of time needed to find out whether a clinical complete response to dostarlimab equates to cure," Sanoff explains, noting that we also need larger-scale replication of the results to be sure of the drug's benefits, which so far have only been seen in a minority of patients with MMRd tumors.

"Whether the results of this small study conducted at Memorial Sloan Kettering Cancer Center will be generalizable to a broader population of patients with rectal cancer is also not known."

Bearing these caveats in mind, there's a lot to be hopeful for here; the researchers are already investigating whether their singular immunotherapy approach could also help patients with other tumors that have MMRd, such as some types of stomach, prostate, and pancreatic cancer.

It's early days, and there's still a lot we don't know, but if further research can replicate the bright promise hinted at here, we might be witnessing the development of a new kind of cancer therapy, Sanoff says.

"Despite these uncertainties, Cercek and colleagues and their patients who agreed to forgo standard treatment for a promising but unknown future with immunotherapy have provided what may be an early glimpse of a revolutionary treatment shift," Sanoff writes.

"If immunotherapy can be a curative treatment for rectal cancer, eligible patients may no longer have to accept functional compromise in order to be cured."

The findings are reported in The New England Journal of Medicine.

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In recent months, startups working on solid-state batteries have made steady progress towards those goals. Little battery cells that once sputtered after being charged are growing up into bigger ones that go much longer. There’s still a ways to go until those cells are road-ready, but progress is setting up the next challenge: Once you’ve built a good-enough battery under painstaking lab conditions, how do you build millions of them quickly? “These companies are going to have to have a massive mindset change, going from being R&D companies to manufacturing companies,” says Venkat Srinivasan, director of the Argonne Collaborative Center for Energy Storage Science. “It’s not going to be simple.”

In recent weeks, Solid Power, among the more lavishly funded of those solid-state companies, has fired up a pilot line in Colorado that it hopes will address that question. At full capacity, it will produce 300 cells per week, or about 15,000 per year. That’s a trickle compared with the millions of cells produced each year by gigafactories, and getting there will still take months of finessing tools and processes. But the goal, according to CEO Doug Campbell, is to start delivering cells to car makers like BMW and Ford for automotive testing by the end of the year.

Once the automakers are happy with how the batteries do on the road, the company plans to pass the baton to one of its gigafactory-owning battery partners, like the Korean battery behemoth SK Innovation. According to Campbell, that should be relatively simple. Solid Power has designed what he describes as a uniquely manufacturable “flavor” of solid-state design that allows battery makers to reuse existing processes and equipment designed for lithium-ion batteries. “In an ideal world, this is the last cell production line that’s operated by Solid Power,” he says of the Colorado facility.

In principle, that makes sense. A battery is a battery. Like their liquid-filled cousins, solid-state batteries require an anode, a cathode, and some way for ions to migrate between the two. That’s where the electrolyte comes in. But it’s not easy to make something that’s porous to ions, yet solid enough not to crack. Researchers have spent years looking for the right materials, eventually settling on a range of ideas that include ceramics and plasticky polymers. But not all of them are easy to make. Some are incredibly brittle, liable to fall apart when they’re made or when they’re slotted between the electrodes; others are softer and more pliant, but can’t be exposed to moisture. Plus, battery scientists don’t have a lot of practice producing the kinds of precursor materials that are required to make them. The history just isn’t there.

The second problem is the anode. The holy grail for solid-state involves changing up the anode from the typical graphite to lithium metal. Couple that with a solid electrolyte and it’s a recipe for immense amounts of energy. The trouble is the form that lithium metal takes. Battery makers are used to working with powdered materials for the anode and cathode that can be rolled out as a slurry. But lithium works best as a thin, free-standing foil—in the case of Solid Power’s, it’s 35 microns thick. “It has the consistency of wet tissue paper,” Campbell says. “And so you can imagine when you're making literally kilometers of material, it gets very tricky.”

Lithium offers other kinds of trouble. Over time, and especially when the battery is forced to charge up fast, lithium ions can form dendrites—tendrils of metal that wind their way between the electrodes and eventually cause the battery to short. It sounds scary—and in an old-school lithium-ion battery it could be a recipe for a fire. But in lab tests of solid-state batteries, it hasn’t proven dangerous because the solid electrolyte isn’t flammable. Mostly, it’s just inconvenient, because it affects how many times the battery can be charged.

A few years ago, Solid Power set aside lithium in favor of an anode that’s mostly made of silicon. It was a practical move, Campbell says. No more messy foil, no more short circuits. Luckily for Solid Power, the sulfide that they chose starts off in a powder form too. For battery makers, it’s familiar stuff.

Those choices have trade-offs. Swapping out the lithium anode for silicon means adding more weight to the battery, putting a limit on how much energy it can pack. The design is still poised to be a big improvement over lithium-ion. But, well … it could be better. Campbell says the company is still working on a lithium design, though it will lag a year or two behind the silicon version. In the meantime, lithium metal manufacturing can catch up.

That kind of incremental approach is likely a smart idea, says Shirley Meng, a battery scientist at the University of Chicago. Large battery makers have gotten immensely better at making lithium-ion batteries over the past 30 years, she points out, designing massive factories and better automation that has driven down costs. “We don’t want to reinvent all the machines,” she says. “We want to drop in the solid-state and only make small tweaks. That’s the most ideal situation.”

But there’s a risk of being leap-frogged. Solid State’s archrival, Quantumscape, uses a different kind of proprietary ceramic and a lithium-based design that requires a distinct set of manufacturing processes. The company has suggested it plans to build its own factories, rather than try to retool or replicate ones already out there. The company, which is currently building out a pre-pilot production line in California, told investors in an earnings call last month that it hopes to deliver batteries to automakers for testing sometime next year.

Both companies—and a slew of competitors—are still likely years away from putting their batteries in vehicles that are for sale. As the size of the batteries increases—measured in layers—tiny imperfections compound, which poses a particular problem for scaling up. A lithium-ion battery maker that’s really good at what it does might find that only 80 to 90 percent of its cells are actually usable. They’re constantly fighting to inch that number upwards. For solid-state batteries, expect that number to start off way lower. “This is probably the biggest challenge that everybody will be dealing with,” Srinivasan says.

For Solid Power, the current EV-size cells don’t do as well as they should in cold temperatures, and battery life declines too fast when the cells are repeatedly fast-charged. But Campbell says that working out the kinks in smaller versions of the battery gives him optimism. “It gives us the confidence that the chemistry is right,” he says. “This is not a chemistry problem. This is an engineering problem.”

The Next Challenge for Solid-State Batteries? Making Lots of Them

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Epigenetics is the study of the chemical changes that happen to DNA throughout a lifetime, which in turn affect the expression of genes. These changes can occur as a result of a person’s behavior (such as through diet or smoking) or environmental exposures (such as to toxins or ultraviolet rays). Epigenetics is a kind of molecular memory that reflects the experiences that we’ve encountered over many years. It’s the reason why, among identical twins who share the same DNA code, one may develop cancer while the other remains healthy.

While gene editing relies on changing the DNA code itself, epigenetic editing involves dialing the expression of individual genes up or down. Genes contain instructions to make vital proteins, and their expression is the process by which a gene gets switched “on” to make them. If you think of your genes as volume knobs on a soundboard, epigenetic editing controls how “loud” or “soft” their settings are.

Experimenting with those volume controls is a new field, but a study published in May in the journal Science Advances offers an intriguing peek at one possible application: countering the way early alcohol use modifies how genes work. In previous research, scientists had found that binge drinking during adolescence alters brain chemistry in the amygdala—the small, almond-shaped part of the brain that controls fear and pleasure responses. In both rodents and in people, they found that exposure to alcohol early in life seems to decrease the expression of a gene called Arc. This gene is a major regulator of plasticity, or the brain’s ability to adapt based on experience. When Arc’s expression is turned down, the change is associated with a predisposition to anxiety and alcohol use disorder in adulthood.

For the new study, a team led by Subhash Pandey, a psychiatry professor and director of the Center for Alcohol Research in Epigenetics at the University of Illinois Chicago, wanted to see if they could reverse this change—in rats—by epigenetically editing Arc in their amygdalas. They built a modified form of Crispr that, instead of editing or deleting the gene, turns up its expression. They then injected it into the brains of adult rats that had been exposed to alcohol during their adolescence—the equivalent of ages 10 to 18 for a human. That early exposure meant Arc’s expression was already depressed in the adult animals. “We targeted the central nucleus of the amygdala, because this is a critical hub for processing the information coming to the brain and is also a center for anxiety, fear, and drinking behavior,” says Pandey.

The Crispr injection brought Arc expression back up to baseline levels, what Pandey refers to as a “factory reset” for the brain. Afterward, these rodents consumed less alcohol and were less anxious—something the researchers measured through behavioral testing, including how the rats behaved in what’s known as an “elevated plus maze.” The cross-shaped maze consists of two arms that are exposed to the open air and two arms that are enclosed. The more stressed the rodents are, the less time they like to spend in the open-air parts of the maze.

“We didn't see any indication of their drinking coming back to baseline, so we think that maybe this epigenetic editing will produce a long-lasting effect,” Pandey says. “I think a lot more work needs to be done in terms of how this can be translated into humans for a therapy, but I have high hopes.”

To test that the Arc gene was truly responsible for this outcome, the researchers also designed a Crispr injection meant to decrease its expression. They tested it in rats that weren’t exposed to alcohol in adolescence. Following the injection, the rats had more anxiety and consumed more alcohol than they did before.

The study raises the possibility that our molecular memory could be revised—or even erased. “I'm struck deeply by this work showcasing the feasibility of changing a gene's memory of its experience,” says Fyodor Urnov, a professor of genetics at the UC Berkeley and scientific director at the Innovative Genomics Institute of UC Berkeley and UC San Francisco. But, he continues, rats aren’t humans, and we shouldn’t leap to conclusions. “The distance between curing a rat and injecting a human being with addiction to alcohol with an epigenetic editor is a formidable one,” says Urnov. “I think that we are quite a ways away from somebody who has developed a mild drinking problem becoming eligible for a quick injection into their amygdala.”

That said, Urnov, who is also the cofounder of Tune Therapeutics, an epigenetic editing company, could see an experimental therapy like this being tested among people with alcohol addiction who have relapsed from treatment several times and have no other therapeutic options left.

Yet, as with directly editing genes, there could be unintended consequences of tweaking their expression. Because Arc is a regulator gene involved in brain plasticity, modifying its expression could have effects beyond alcohol addiction. “We don't know what other behaviors are altered by this change,” says Betsy Ferguson, a professor of genetics at Oregon Health and Science University who studies epigenetic mechanisms in addiction and other psychiatric disorders. “It’s a balance between finding something that's effective and something that's not disruptive to everyday life.”

Another complicating factor is that the expression of dozens, perhaps hundreds, of genes are altered by alcohol use over time. In people, it may not be as simple as turning up the expression of Arc, which is only one of them. While it may seem like the solution would be to tweak all of those genes, manipulating the expression of many at once could cause problems. “Knowing that behaviors, including alcohol use behaviors, are regulated by a number of genes, it's really a challenging problem to solve,” Ferguson says.

And it’s not clear how long the effects of such editing might last. Epigenetic changes that occur naturally can be temporary or permanent, says Ferguson. Some can even be passed onto future generations. Overall, she finds the idea of using epigenetic editing to treat alcohol addiction fascinating, but she’d want to see the results replicated and the Crispr treatment tried in larger animals that more closely mimic humans. 

That day may not be too far off, as a handful of companies have recently launched to commercialize epigenetic editing. At Navega Therapeutics, which is based in San Diego, researchers are studying how to treat chronic pain by turning down the expression of a gene called SCN9A. When it’s highly expressed, it sends out lots of pain signals. But it would be a bad idea to simply delete this gene, because some amount of pain is useful; it signals when something is going wrong within the body. (In rare cases, people with an SCN9A mutation that effectively renders it inactive are immune to pain, which makes them vulnerable to injuries they aren’t able to sense.) In experiments at Navega, epigenetic editing in mice seemed to repress pain for several months.

Urnov’s Tune Therapeutics, meanwhile, plans to use epigenetic editing for a broad range of conditions, including cancer and genetic diseases. Though Urnov doesn’t see epigenetic editing as the antidote to binge drinking, he thinks this proof-of-concept study shows that it may be possible to rewire our genes’ experiences to reverse some of the damage of early alcohol abuse. “It is empowering, frankly, to consider the fact that we now have genome editing to fight a drug’s pernicious action right at the venue where the drug inscribes its memories onto the brain,” he says.

A New Kind of Genome Editing Is Here to Fine-Tune DNA

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Gut check: Fossil finds give us a history of life—and what it ate

Anne Ellis, chair of Queen's Division of Allergy and Immunology and clinical scientist at Kingston Health Sciences Center (KHSC), is paying close attention to how seasonal allergies have changed in the past decade. She has some disconcerting news: it is still hard to distinguish patterns and make assertive predictions.

"Every year is different," she says. "This year's tree pollen season actually started on time compared to 10 years ago, but in more recent past we've had a very late start to tree pollen season, owing to much longer winters."

Changing cycles

While 2021 saw record-breaking levels of birch pollen, so far 2022 has been more typical in terms of overall counts for Southern Ontario. In April, however, warmer days followed by cold nights and even snow brought pollination to a halt.

"Expect the unexpected when it comes to your allergies," is Dr. Ellis' main advice for those reaching for their antihistamines each spring.

But Dr. Ellis believes shortening spring and fall seasons—with longer winter and summer—make a big difference, at least in how people perceive their allergy symptoms.

"We wind up with a longer winter and more time to 'forget' how bad our seasonal allergies can be, so they affect us more dramatically when they come back," she says.

North America is also seeing hotter summers with higher humidity, which can be a challenge for people with asthma. Because humidity fuels dust mite growth, even staying indoors doesn't always provide relief—at least if one doesn't have air conditioning or a dehumidifier.

Some practical tips

Dr. Ellis recommends that people suffering from seasonal allergies keep their windows closed and the air conditioning on when possible, and to avoid hanging clothes on clotheslines outside to prevent pollen capture. Rinsing the nose with a saline solution might help, too.

At local pharmacies, people can look for non-sedating, second generation antihistamines such as cetirizine or loratadine—Dr. Ellis says it's better to avoid older, sedating antihistamines that might have unintended side effects and are not as effective as the new ones. If over the counter medicines are not enough to provide relief, she suggests seeing a doctor for prescription medications such as new antihistamines and intranasal corticosteroids, which reduce swelling and mucus in the nose.

In case these tips don't do the trick, seeing a specialist might be the best option.

"Ask your doctor for a referral to an allergist to be skin tested and find out what you are allergic to specifically," advises Dr. Ellis. "An allergist can offer customized immunotherapy options based on these results that actually treat the underlying allergy, rather than just masking symptoms."

From a public health perspective, Dr. Ellis says urban planning can make a difference, for example, in planting female trees that don't pollinate—while they drop nuts and fruits, which can be messy, they don't cause increases in pollen counts.

Research in action

Dr. Ellis leads the Kingston Environmental Exposure Unit at KHSC. In this facility, she and her team have a meticulously controlled environment that allows them to study the impact of allergens in health at any time of the year.

"The highly controlled indoor environment eliminates the variables of weather, participant environment, and the changing characteristics of seasonal allergens," explains Dr. Ellis. "A proprietary computer-controlled delivery system and stringent monitoring ensure that the levels of allergen maintained in the unity remain within specific requirements."

Since the 1980s, the unit has been used to advance our knowledge of how effective different anti-allergic treatments can be, including antihistamines, nasal corticosteroids and other medications.

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Illness from C. diff typically occurs after using antibiotics. It most commonly affects older adults in hospitals or long-term care facilities. About 200,000 people in the U.S. are infected annually with C. diff in a hospital or long-term care setting. These numbers are lower than in previous years because of improved prevention measures.

Signs and symptoms of C. diff infection usually develop within five to 10 days after starting a course of antibiotics. However, they may occur as soon as the first day or up to three months later.

The most common signs and symptoms of mild to moderate C. diff infection are watery diarrhea and mild abdominal cramps. Additional signs and symptoms of severe infection include rapid heart rate, dehydration, fever and nausea.

Complications of C. diff infection include dehydration, kidney failure, colon damage and death.

A person is treated only when showing signs or symptoms of infection. Treatments can include antibiotics and surgery to remove the diseased portion of the colon. People who carry the bacteria but are not sick are not treated.

Approximately 25% of people treated for C. diff infection get sick again, either because the initial infection never went away or because they've been reinfected with a different strain of the bacteria. The risk increases with each C. diff infection episode, with the risk of getting sick again exceeding 50% after three or more infections. Additional treatment options for recurrent disease may include fecal microbiota transplant.

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It's been known for centuries that noble metals like platinum, gold, ruthenium, and palladium make excellent catalysts for chemical reactions, because they help break the chemical bonds between atoms more efficiently than other metals.

But noble metals are rare and expensive, so large-scale industrial manufacturers generally opt for cheaper, less effective alternatives like iron. (Iron is used as a catalyst in the mass production of fertilizer, for instance.)

The downside to using poorer quality catalysts is that chemical reactions must be heated up to high temperatures, which increases the carbon footprint for many industrial processes.

In a record-breaking achievement, researchers from UNSW Sydney and RMIT in Australia have dissolved platinum in liquid gallium, splitting the platinum atoms up so that there was more catalytic potential in a smaller amount of platinum.

Platinum normally has a melting temperature of 1,700 °C (3,092 Fahrenheit), which means it is usually a solid when used as a catalyst.

By infusing platinum into a gallium matrix, it adopts the melting point of gallium – a soft, silvery and non-toxic metal that melts basically at room temperature of 29.8 °C. One useful characteristic of liquid gallium is that it dissolves metals (like water dissolves salt and sugar) by separating the individual atoms in each molecule.

The invention has the potential to save on energy costs and lower emissions in industrial manufacturing, the researchers say.

"A range of important chemical reactions could be performed at relatively low temperature with the use of a more efficient catalyst like liquid platinum," lead author and chemical engineer Md. Arifur Rahim from UNSW Sydney told ScienceAlert.

Scientists have been trying to make expensive noble metal catalysts more affordable through a process of "miniaturization" since 2011, explains Rahim.

When metals are solid, only the atoms on the outside can be used in reactions, so there's a lot of waste. If you break this solid down into smaller and smaller clumps (think nanoparticles), you get a more efficient reaction as more metal atoms can muscle in – many hands make light work.

The most efficient and tiniest system would make each individual atom available to do the work of a catalyst.

"When you miniaturize the system, you're maximizing the surface-to-volume ratio and the atom utilization efficiency so that your overall consumption of the catalyst is smaller over time, and that can possibly make your product affordable," says Rahim.

"Theoretically, you get the maximum efficiency of that catalytic metal when it is at the atomic scale, because you cannot go beyond that."

In single-atom catalysts, the bonds holding the catalyst together are split and each atom is individually anchored in a substance called a matrix.

So, Rahim and colleagues tested gallium as their matrix. Once dissolved in gallium, they found that every platinum atom was split from every other platinum atom, making it a perfect miniature catalyst.

"When dissolved, platinum atoms are spatially dispersed in the liquid gallium matrix without atomic clustering (i.e., the absence of platinum-platinum bonding) that can drive different catalytic reactions with remarkable mass activity," the researchers write in their paper.

Platinum is mobile when it's in a liquid matrix, and much less prone to the problem of coking, where solid catalysts get covered in carbon and need to be cleaned before they can be reused.

Gallium isn't as cheap as iron. But it can be used again and again for the same reactions. This is because, like platinum, gallium doesn't get deactivated or degrade during the reaction.

The process of dissolving platinum in gallium requires raising the temperature to about 400 °C for a few hours. But it's a one-time investment of energy that saves further temperature hikes later during the chemical manufacturing process, the researchers say.

The team hopes their technique will lead to much cleaner and cheaper products, from fertilizer to green fuel cells.

The study was published in the journal Nature Chemistry.

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As the atoms of arithmetic, prime numbers have always occupied a special place on the number line. Now, Jared Duker Lichtman, a 26-year-old graduate student at the University of Oxford, has resolved a well-known conjecture, establishing another facet of what makes the primes special — and, in some sense, even optimal. “It gives you a larger context to see in what ways the primes are unique, and in what ways they relate to the larger universe of sets of numbers,” he said.

The conjecture deals with primitive sets — sequences in which no number divides any other. Since each prime number can only be divided by 1 and itself, the set of all prime numbers is one example of a primitive set. So is the set of all numbers that have exactly two or three or 100 prime factors.
Primitive sets were introduced by the mathematician Paul Erdős in the 1930s. At the time, they were simply a tool that made it easier for him to prove something about a certain class of numbers (called perfect numbers) with roots in ancient Greece. But they quickly became objects of interest in their own right — ones that Erdős would return to time and again throughout his career.

That’s because, though their definition is straightforward enough, primitive sets turned out to be strange beasts indeed. That strangeness could be captured by simply asking how big a primitive set can get. Consider the set of all integers up to 1,000. All the numbers from 501 to 1,000 — half of the set — form a primitive set, as no number is divisible by any other. In this way, primitive sets might comprise a hefty chunk of the number line. But other primitive sets, like the sequence of all primes, are incredibly sparse. “It tells you that primitive sets are really a very broad class that’s hard to get your hands on directly,” Lichtman said.

To capture interesting properties of sets, mathematicians study various notions of size. For example, rather than counting how many numbers are in a set, they might do the following: For every number n in the set, plug it into the expression 1/(n log n), then add up all the results. The size of the set {2, 3, 55}, for instance, becomes 1/(2 log 2) + 1/(3 log 3) + 1/(55 log 55).

Erdős found that for any primitive set, including infinite ones, that sum — the “Erdős sum” — is always finite. No matter what a primitive set might look like, its Erdős sum will always be less than or equal to some number. And so while that sum “looks, at least on the face of it, completely alien and vague,” Lichtman said, it’s in some ways “controlling some of the chaos of primitive sets,” making it the right measuring stick to use.

With this stick in hand, a natural next question to ask is what the maximum possible Erdős sum might be. Erdős conjectured that it would be the one for the prime numbers, which comes out to about 1.64. Through this lens, the primes constitute a kind of extreme.

Over the decades, mathematicians made partial progress toward a proof. They showed, for instance, that the conjecture was true for particular types of primitive sets.

Still, “it felt like we weren’t really all that close to it before Jared started working on it,” said Greg Martin, a mathematician at the University of British Columbia who has worked on related problems. András Sárközy, a mathematician at Eötvös Loránd University in Hungary and a frequent collaborator of Erdős, concurred. “It certainly seemed beyond reach,” he said.

Lichtman started working on the primitive set conjecture in 2018, during his last year as an undergraduate at Dartmouth College. “I was immediately fascinated with this question. It was just very mysterious how anything like this would be true,” he said. “It’s been my constant companion for the past four years.”

In 2019, he and Carl Pomerance, his adviser at Dartmouth — who, according to Lola Thompson, a mathematician at Utrecht University and a former student of Pomerance, essentially “came out of retirement to work with him” — found that a primitive set’s Erdős sum could be no greater than around 1.78. “It’s not too far off,” Martin said. “Only about 10% bigger than the conjecture for the primes.”

Lichtman and Pomerance obtained this constant by associating a new sequence of multiples to each number in a given primitive set. Consider again the primitive set {2, 3, 55}. Associated to the number 2 would be the sequence of all even numbers. Associated to the number 3 would be all multiples of 3 that are not also multiples of 2. And associated to the number 55 (5 × 11) would be all multiples of 55 whose smallest prime factor is 11 (therefore excluding all multiples of 2, 3, 5 and 7). Lichtman likens it to how words are indexed in a dictionary — only with primes used instead of letters to organize each sequence.

Merrill Sherman/Quanta Magazine

He and Pomerance then thought about how “dense” these sequences of multiples were — that is, how much of the number line they occupied. (For instance, the sequence of all even numbers has a density of 1/2, since even numbers make up half of all numbers.) They observed that if the original set was primitive, then its associated sequences of multiples wouldn’t overlap, and therefore their combined density was at most 1 — the density of all the whole numbers.

This observation was relevant because a 19th-century theorem by the mathematician Franz Mertens essentially allowed Lichtman and Pomerance to reinterpret the Erdős sum of a primitive set in terms of these densities. According to Mertens’ theorem, a special constant (roughly equal to 1.78), when multiplied by a term equivalent to the combined densities of these multiples, gave a maximal value for what the Erdős sum of a primitive set could be. And since the combined density was at most 1, Lichtman and Pomerance proved that the Erdős sum of a primitive set was at most around 1.78.

“It was a variation of Erdős’ original ideas, but it was a very slick, neat way … of getting a not-tight but not-too-bad upper bound,” said James Maynard, a mathematician at Oxford.

And for a few years, that seemed like the best mathematicians could do. It wasn’t clear how to drive that maximum down to 1.64. In the meantime, Lichtman graduated and moved to Oxford to do his doctorate with Maynard, where he’s mainly been working on other problems related to the primes.
“I knew he’d been thinking about this problem quite a lot on the side,” Maynard said, “but it was a complete shock when he suddenly, seemingly out of the blue, came up with a complete proof.”

Lichtman first realized that for numbers with relatively small prime factors, his earlier argument with Pomerance could still work: It was relatively straightforward to show that in this case, the constant 1.78 could be driven down to well below 1.64.

But numbers with relatively large prime factors — which are “close” to the primes in some sense — were another story. To deal with them, Lichtman found a way to associate not just one sequence of multiples to each number, but several sequences. As before, the combined density of all those sequences was at most 1. But this time, “these other multiples will kind of grow like weeds and take over some of the space,” Lichtman said.

Take the number 618 (2 × 3 × 103). Typically, you might associate to it all multiples of 618 whose smallest prime factor is 103. But sequences could instead be constructed using some of the smaller prime factors that were omitted. For instance, a sequence might consist of all the original multiples, while also permitting multiples of 618 that are divisible by 5. (Some constraints dictate which smaller prime factors can be used.)

The presence of these additional multiples meant that the combined density of the original multiples — the quantity that gets used in Mertens’ theorem — was actually less than 1. Lichtman found a way to put a more precise bound on what that density might be.

He then carefully determined what the worst-case scenario for a primitive set might look like: what balance it would strike between numbers with large prime factors and numbers with small prime factors. By patching together the two parts of his proof, he was able to show that the Erdős sum for such a scenario comes out to a value that’s less than 1.64.

“There’s this numerical moment of truth,” Maynard said. “I don’t know if it’s luck or what, that this is numerically just enough.”

Lichtman posted his proof online in February. Mathematicians noted that the work is particularly striking because it relies entirely on elementary arguments. “It wasn’t like he was waiting for all this crazy machinery to develop,” Thompson said. “He just had some really clever ideas.”

Those ideas have now cemented the primes as exceptional among the primitive sets: Their Erdős sum reigns supreme. “We all think of the primes as special,” Pomerance said. “And this just adds to their luster.”

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This tracked data helps the likes of Google and Facebook earn billions and billions of dollars a year in advertising revenue, as they use the information to target adverts at us.

For example, if you are browsing online fashion retailers to potentially buy a new pair of jeans, you should very soon see adverts for the denim trousers appearing elsewhere on your computer screen. We have all seen this happen regarding whatever we were thinking of purchasing.

The level to which we are being tracked online in this way is somewhat unnerving. The average European has data about his or her internet usage shared 376 times a day, according to one recent study. For US surfers this almost doubles to 747.

But what if you could not only have more control over how much of your data is shared, but actually make money from it?

That is the promise is of a Canadian tech firm called Surf, which last year launched a browser extension of the same name. It rewards people for surfing the internet.

Surf wants to be "the frequent flyer rewards of internet browsing"

Still in its beta or limited release stage, it works by bypassing the likes of Google, and instead sells your data directly to retail brands. In return Surf gives you points that can be saved up and then redeemed for shop gift cards and discounts.

Firms signed up so far include Foot Locker, The Body Shop, Crocs, and Dyson.

Surf points out that all the data is anonymous - your email addresses and telephone numbers are not shared, and you don't have to give your name when you sign up. It does however ask for your age, gender and approximate address, but these are not compulsory.

The idea is that brands can use the data that Surf provides to, for example, see what are the most popular websites among 18 to 24-year-old men in Los Angeles. Then can then target their adverts accordingly.

Surf hasn't released details of how much people can earn, but so far it says it has enabled users to collectively earn more than $97,000 (£77,000).
People can also use Surf to limit what data they share, such as blocking information about certain websites they visit.

One Surf user is York University student Aminah Al-Noor, who says she feels that the extension has given her "the control back" over her online data.

Aminah Al-Noor is able to earn points that can be redeemed for shopping vouchers from a number of retailers

"You can pick what you want to give Surf," adds the 21-year-old. "And other times I forget that I have it on, and a week later I will check, and my points just keep going up.

"All tech companies are going to collect our information, but the point is to make our experiences using the technology better, right," adds the 21-year-old.

New Tech Economy is a series exploring how technological innovation is set to shape the new emerging economic landscape.

Surf's founder and chief executive Swish Goswamo says the firm wants to be "the frequent flyer rewards of internet browsing".

He adds: "From day one we have been clear with users on what we share and don't share, and we give them the ability to control their data as well.

"I think if you are upfront with people, and letting them know you are sharing data with brands, and you are doing it in an anonymised way - i.e. it cannot come back to them because we don't have their first or last name, then people are more comfortable to say 'yes' and share more with us."

Surf is part of a growing movement that some commentators have dubbed "responsible technology", part of which is to give people more control over their data.

Another tech firm in this space is fellow Canadian start-up Waverly, which allows people to compile their own news feeds rather than rely on Google News and Apple News' tracker and advertising-based algorithms.

With Waverly, you fill out the topics you are interested in, and its AI software finds articles it thinks you'd like to read. The Montreal-based firm is the brainchild of founder Philippe Beaudoin who was formerly a Google engineer.

Philippe Beaudoin wants people to pick what comes up in their new feeds

Users of the app can change their preferences regularly and send feedback on what articles are being recommended to them.

Mr Beaudoin says that users have to make a bit of effort, in that they have to tell the app the stuff they are interested in, but that in return they are freed from being "being trapped by advertisements".

"Responsible tech should empower users, but it also shouldn't shy from asking them to do some work on their behalf," he says.

"[In return] our AI reads thousands of articles a day, and places them in an index [for users]."

Rob Shavell's US firm Abine, makes two apps that enable the user to increase his or her privacy - Blur and Delete Me. The former ensures that your passwords and payment details cannot be tracked, while the later removes your personal information from search engines.

Mr Shavell says his view is that the surfing the internet should come with "privacy by design".

Carissa Veliz, an associate professor at Oxford University's Institute for Ethics in AI, says that tech firms need to be "incentivised to develop business models that do not depend on the exploitation of personal data".

Carissa Veliz wonders if regulators should take a closer look at the internet giants' algorithms

"It is worrisome that most of the algorithms that are ruling our lives are being produced by private companies without any kind of supervisions or guidance to make sure those algorithms are supportive of our public goods and values," she adds.

"I don't think transparency is a panacea, or even half of the solution, but policymakers in particular should have access to the algorithms."

Google points to its new "Privacy Sandbox" initiative, which has "the goal of introducing new, more private advertising solutions".

A Google spokesperson says: "That's why we're collaborating with regulators and the web community to create technologies, through the Privacy Sandbox, that will protect people's privacy online while helping keep online content and services free for all.

"Later this year, we'll launch My Ad Center, which expands our privacy controls to give people more direct control over the information used to show them ads."

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What is the Tiangong space station?

Last year, China put into orbit the first module of its Tiangong or "Heavenly Palace" space station. It plans to add more modules, such as Mengtian science lab, by the end of the year.

Next year, it will launch a space telescope, called Xuntian. This will fly close to the space station, and dock with it for servicing and refuelling.

Tiangong will have its own power, propulsion, life support systems and living quarters.

China is only the third country in history to have put both astronauts into space and to build a space station, after the Soviet Union (and now Russia) and the US.

It has big ambitions for Tiangong and hopes it will replace the International Space Station (ISS), which is due to be decommissioned in 2031.

Chinese astronauts are excluded from the ISS because US law bans its space agency, Nasa, from sharing its data with China.

China's plans to reach the Moon and Mars

China's ambitions do not end there.

A few years from now it wants to take samples from asteroids near the Earth.

By 2030, it aims to have put its first astronauts on the Moon, and to have sent probes to collect samples from Mars and Jupiter.

What are other countries doing?

As China expands its role in space, several other countries are also aiming to get to the Moon.

Nasa plans to return to the Moon with astronauts from the US and other countries from 2025 onwards and has already rolled its new giant SLS rocket at the Kennedy Space Center,

Japan, South Korea, Russia, India, the United Arab Emirates are also working on their own lunar missions.

India has launched its second major Moon mission already and wants to have its own space station by 2030.

Meanwhile, the European Space Agency, which is working with Nasa on Moon missions, is also planning a network of lunar satellites to make it easier for astronauts to communicate with Earth.

Who makes the rules for space?

•  The UN Outer Space Treaty of 1967 says nowhere in space can be claimed by any one nation

•  The UN Moon Agreement of 1979 says space should not be commercially exploited, but the US, China and Russia have refused to sign

•  Now, the US is promoting its Artemis Accords, spelling out how nations can exploit the Moon's minerals in a co-operative way

•  Russia and China won't sign the Accords, saying the US has no right to make the rules for space

What is China's history in space?

China put its first satellite into orbit in 1970 - as it went through massive disruptions caused by the Cultural Revolution.

The only other powers to have gone into space by that stage were the US, the Soviet Union, France and Japan.

In the past 10 years, China has launched more than 200 rockets.

It has already sent an unmanned mission to the Moon, called Chang'e 5, to collect and return rock samples. It planted a Chinese flag on the lunar surface - which was deliberately bigger than previous US flags.

With the launch of Shenzhou 14, China has now put 14 astronauts into space, compared with 340 by the US and more than 130 by the Soviet Union (and now Russia).

But there have been setbacks. In 2021, part of a Chinese rocket tumbled out of orbit and crashed into the Atlantic Ocean and two launches failed in 2020.

Who is paying for China's space programme?

Chinese state media Xinhua said at least 300,000 people have worked on China's space projects - almost 18 times as many as currently work for Nasa.
The Chinese National Space Administration was set up in 2003 with an initial annual budget of two billion yuan ($300m, £240m).

However, in 2016 China opened its space industry to private companies, and these are now investing more than 10 billion yuan ($1.5bn, £1.2bn) a year, according to Chinese media.

Why is China going into space?

China is keen to develop its satellite technology, for telecommunications, air traffic management, weather forecasting and navigation and more.
But many of its satellites also have military purposes. They can help it spy on rival powers, and guide long-range missiles.

Lucinda King, space project manager at Portsmouth University, says China is not just focussing on high-profile space missions: "They are prolific in all aspects of space. They have the political motivation and the resources to fund their planned programmes."

China's Moon missions are partly motivated by the opportunities to extract rare earth metals from its surface.

However, Prof Sa'id Mosteshar, director of the London Institute of Space Policy and Law at the University of London, says it probably would not pay for China to send repeated mining missions to the Moon.

Instead, he says China's space programme is driven more by a desire to impress the rest of the world. "It's a projection of power and a demonstration of technological advancement."

Additional reporting by Jeremy Howell and Tim Bowler

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In the early 2000s, Souza and colleagues came to understand that 90 percent of deforestation occurs within 5 kilometers of newly created roads. While satellites have long been able to track road expansion, the old way of doing things required people to label those findings by hand, amassing what would eventually become training data. Those years of labor paid off last fall with the release of an AI system that Imazon says reveals 13 times more roadway than the previous method, with an accuracy rate of between 70 and 90 percent.

Proponents of satellite imagery and machine learning have ambitious plans to solve big problems at scale. The technology can play a role in anti-poverty campaigns, protect the environment, help billions of people obtain street addresses, and increase crop yields in the face of intensifying climate change. A UNESCO report published this spring highlights 100 AI models with the potential to transform the world for the better. But despite recent advances in deep learning and the quality of satellite imagery, as well as the record number of satellites expected to enter orbit over the next few years, ambitious efforts to use AI to solve big problems at scale still encounter traditional hurdles, like government bureaucracy or a lack of political will or resources.

Stopping deforestation, for instance, requires more than spotting the problem from space. A Brazilian federal government program helped reduce deforestation from 2004 to 2012 by 80 percent compared to previous years, but then federal support waned. In keeping with an election promise, President Jair Bolsonaro weakened enforcement and encouraged opening the rainforest to industry and cattle ranch settlers. As a result, deforestation in the Amazon reached the highest levels seen in more than a decade.

Other AI-focused conservation groups have run into similar issues. Global Fishing Watch uses machine learning models to identify vessels that turn off GPS systems to avoid detection; they’re able to predict the type of ship, the kind of fishing gear it carries, and where it’s heading. Ideally that information helps authorities around the world target illegal fishing and inform decisions to board boats for inspection at sea, but policing large swaths of the ocean is difficult. Global Fishing Watch’s tech spotted hundreds of boats engaged in illegal squid fishing in 2020, data that head of research David Kroodsma credits with increasing cooperation between China and South Korea, but it didn’t lead to any particular prosecution. Enforcement in ports, he says, is “key to making deterrence scalable and affordable.”

Back on land, the consulting company Capgemini is working with The Nature Conservancy, a nonprofit environmental group, to track trails in the Mojave Desert and protect endangered animal habitats from human activity. In a pilot program last year, the initiative mapped trails created by off-road vehicles in hundreds of square miles of satellite imagery in Clark County, Nevada, to create an AI model that can automatically identify newly created roads. Based on that work, The Nature Conservancy intends to expand the project to monitor the entirety of the desert, which stretches more than 47,000 square miles across four US states.

However, as in the Amazon, identifying problem areas only gets you so far if there aren’t enough resources to act on those findings. The Nature Conservancy uses its AI model to inform conversations with land managers about potential threats to wildlife or biodiversity. Conservation enforcement in the Mojave Desert is overseen by the US Bureau of Land Management, which only has about 270 rangers and special agents on duty.

In northern Europe, the company Iceye got its start monitoring ice buildup in the waters near Finland with microsatellites and machine learning. But in the past two years, the company began to predict flood damage using microwave wavelength imagery that can see through clouds at any time of day. The biggest challenge now, says Iceye’s VP of analytics, Shay Strong, isn’t engineering spacecraft, data processing, or refining machine learning models that have become commonplace. It’s dealing with institutions stuck in centuries-old ways of doing things.

“We can more or less understand where things are going to happen, we can acquire imagery, we can produce an analysis. But the piece we have the biggest challenge with now is still working with insurance companies or governments,” she says.

“It’s that next step of local coordination and implementation that it takes to come up with action,” says Hamed Alemohammad, chief data scientist at the nonprofit Radiant Earth Foundation, which uses satellite imagery to tackle sustainable development goals like ending poverty and hunger. “That’s where I think the industry needs to put more emphasis and effort. It’s not just about a fancy blog post and deep learning model.”

It’s often not only about getting policymakers on board. In a 2020 analysis, a cross-section of academic, government, and industry researchers highlighted the fact that the African continent has a majority of the world’s uncultivated arable land and is expected to account for a large part of global population growth in the coming decades. Satellite imagery and machine learning could reduce reliance on food imports and turn Africa into a breadbasket for the world. But, they said, lasting change will necessitate a buildup of professional talent with technical knowledge and government support so Africans can make technology to meet the continent’s needs instead of importing solutions from elsewhere. “The path from satellite images to public policy decisions is not straightforward,” they wrote.

Labaly Toure is a coauthor of that paper and head of the geospatial department at an agricultural university in Senegal. In that capacity and as founder of Geomatica, a company providing automated satellite imagery solutions for farmers in West Africa, he’s seen satellite imagery and machine learning help decision-makers recognize how the flow of salt can impact irrigation and influence crop yields. He’s also seen it help settle questions of how long a family has been on a farm and assist with land management issues.

Sometimes free satellite images from services like NASA’s LandSat or the European Space Agency’s Sentinel program suffice, but some projects require high-resolution photos from commercial providers, and cost can present a challenge.

“If decision-makers know [the value] it can be easy, but if they don’t know, it’s not always easy,” Toure said.

Back in Brazil, in the absence of federal support, Imazon is now forging ties with more policymakers at the state level. “Right now, there’s no evidence the federal government will lead conservation or deforestation efforts in the Amazon,” says Souza. In October 2022, Imazon signed cooperation agreements with public prosecutors gathering evidence of environmental crimes in four Brazilian states on the border of the Amazon rainforest to share information that can help prioritize enforcement resources.

When you prosecute people who deforest protected lands, the damage has already been done. Now Imazon wants to use AI to stop deforestation before it happens, interweaving that road-detection model with one designed to predict which communities bordering the Amazon are at the highest risk of deforestation within the next year.

Deforestation continued at historic rates in early 2022, but Souza is hopeful that through work with nonprofit partners, Imazon can expand its deforestation AI to the other seven South American countries that touch the Amazon rainforest.

And Brazil will hold a presidential election this fall. The current leader in the polls, former president Luiz Inácio Lula da Silva, is expected to strengthen enforcement agencies weakened by Bolsonaro and to reestablish the Amazon Fund for foreign reforestation investments. Lula’s environmental plan isn’t expected out for a few months, but environmental ministers from his previous term in office predict he will make reforestation a cornerstone of his platform.

Satellites and AI Can Help Solve Big Problems—If Given the Chance

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The Shenzhou 14 crew will spend six months on the Tiangong station, during which they will oversee the addition of two laboratory modules to join the main Tianhe living space that was launched in April 2021.

Their spaceship is due to blast off from the Jiuquan Satellite Launch Center on the edge of the Gobi Desert at 10:44 a.m. Sunday (0244 GMT), the agency said. The crewed space flight program’s workhorse Long March 2F rocket will provide propulsion.

Commander Chen Dong and fellow astronauts Liu Yang and Cai Xuzhe will assemble the three-module structure joining the existing Tianhe with Wentian and Mengtian, due to arrive in July and October. Another cargo craft, the Tianzhou-3, remains docked with the station.

The arrival of the new modules will “provide more stability, more powerful functions, more complete equipment,” said Chen, 43, who was a member of the Shenzhou 11 mission in 2016.

Liu, 43, is also a space veteran and was China’s first female astronaut to reach space aboard the Shenzhou 9 mission in 2012. Cai, 46, is making his first space trip.

China’s space program launched its first astronaut into orbit in 2003, making it only the third country to do so on its own after the former Soviet Union and the U.S.

It has landed robot rovers on the moon and placed one on Mars last year. China has also returned lunar samples and officials have discussed a possible crewed mission to the moon.

China’s space program is run by the ruling Communist Party’s military wing, the People’s Liberation Army, prompting the U.S. to exclude it from the International Space Station.

Chen, Liu and Cai will be joined at the end of their mission for three to five days by the crew of the upcoming Shenzhou 15, marking the first time the station will have had six people aboard.

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