But our new study, published today in the Lancet medical journal, found opioids do not relieve "acute" low back or neck pain (lasting up to 12 weeks) and can result in worse pain.

Prescribing opioids for low back and neck pain can also cause harms ranging from common side effects – such as nausea, constipation and dizziness – to misuse, dependency, poisoning, and death.

Our findings show opioids should not be recommended for acute low back pain or neck pain. A change in prescribing for low back pain and neck pain is urgently needed in Australia and globally to reduce opioid-related harms.

Comparing opioids to a placebo

In our trial, we randomly allocated 347 people with acute low back pain and neck pain to take either an opioid (oxycodone plus naloxone) or placebo (a tablet that looked the same but had no active ingredients).

Oxycodone is an opioid pain medicine which can be given orally. Naloxone, an opioid-reversal drug, reduces the severity of constipation while not disrupting the pain relieving effects of oxycodone.

Participants took the opioid or placebo for a maximum of six weeks.

People in the both groups also received education and advice from their treating doctor. This could be, for example, advice on returning to their normal activities and avoiding bed rest.

We assessed their outcomes over a one-year period.

What did we find?

After six weeks of treatment, taking opioids did not result in better pain relief compared to the placebo.

Nor were there benefits to other outcomes such as physical function, quality of life, recovery time, or work absenteeism.

More people in the group treated with opioids experienced nausea, constipation, and dizziness than in the placebo group.

Results at one year highlight the potential long-term harm of opioids even with short-term use. Compared to the placebo group, people in the opioid group experienced slightly worse pain, and reported a higher risk of opioid misuse (problems with their thinking, mood or behavior, or using opioids differently from how the medicines were prescribed).

More people in the opioid group reported pain at one year: 66 people compared to 50 in the placebo group.

What will this mean for opioid prescribing?

In recent years, international low back pain guidelines have shifted the focus of treatment from drug to non-drug treatment due to evidence of limited treatment benefits and concern of medication-related harm.

For acute low back pain, guidelines recommend patient education and advice, and if required, anti-inflammatory pain medicines such as ibuprofen. Opioids are recommended only when other treatments haven't worked or aren't appropriate.

Guidelines for neck pain similarly discourage the use of opioids.

Our latest research clearly demonstrates the benefits of opioids do not outweigh possible harms in people with acute low back pain and neck pain.

Instead of advising opioid use for these conditions in selected circumstances, opioids should be discouraged without qualification.
Change is possible

Complex problems such as opioid use need smart solutions, and another study we recently conducted provides convincing data opioid prescribing can be successfully reduced.

The study involved four hospital emergency departments, 269 clinicians and 4,625 patients with low back pain. The intervention comprised of:

•     clinician education about evidence-based management of low back pain

•     patient education using posters and handouts to highlight the benefits and harms of opioids

•     providing heat packs and anti-inflammatory pain medicines as alternative pain-management treatments

•     fast-tracking referrals to outpatient clinics to avoid long waiting lists

•     audits and feedback to clinicians on information about opioid prescribing rates.

This intervention reduced opioid prescribing from 63 percent to 51 percent of low back pain presentations. The reduction was sustained for 30 months.

Key to this successful approach is that we worked with clinicians to develop suitable pain-management treatments without opioids that were feasible in their setting.

More work is needed to evaluate this and other interventions aimed at reducing opioid prescribing in other settings including GP clinics.

A nuanced approach is often necessary to avoid causing unintended consequences in reducing opioid use.

If people with low back pain or neck pain are using opioids, especially at higher doses over an extended period of time, it's important they seek advice from their doctor or pharmacist before stopping these medicines to avoid unwanted effects when the medicines are abruptly stopped.

Our research provides compelling evidence opioids have a limited role in the management of acute low back and neck pain. The challenge is getting this new information to clinicians and the general public, and to implement this evidence into practice.

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It tells the true story of Hachiko, the faithful dog that continued to wait for its master at a train station in Japan long after his death.

The cream white Akita Inu, born 100 years ago, has been memorialised in everything from books to movies to the cult science fiction sitcom Futurama. And the Chinese iteration - the third after a Japanese version in 1987, and the Richard Gere-starrer in 2009 - is a hit at the box office.

There have been tales of other devoted hounds such as Greyfriars Bobby, but none with the global impact of Hachiko.

A bronze statue of him has stood outside Shibuya Station in Tokyo, where he waited in vain for a decade, since 1948. The statue was first erected in 1934 before being recycled for the war effort during World War Two. Japanese schoolchildren are taught the story of Chuken Hachiko - or loyal dog Hachiko - as an example of devotion and fidelity.

Hachiko represents the "ideal Japanese citizen" with his "unquestioning devotion", says Professor Christine Yano of the University of Hawaii - "loyal, reliable, obedient to a master, understanding, without relying upon rationality, their place in the larger scheme of things".

The story of Hachiko

Hachiko was born in November 1923 in the city of Odate in Akita prefecture, the original home of Akitas.

A large-sized Japanese dog, the Akita is one of the country's oldest and most popular breeds. Designated by the Japanese government as a national icon in 1931, they were once trained to hunt animals like wild boar and elk.

"Akita dogs are calm, sincere, intelligent, and brave [and] obedient to their masters," said Eietsu Sakuraba, author of an English language children's book about Hachiko. "On the other hand, it also has a stubborn personality and is wary of anyone other than its master."

The year Hachiko was born, Hidesaburo Ueno, a renowned agricultural professor and a dog lover, asked a student to find him an Akita puppy.

Hachiko became nationally known in Japan after a newspaper article in 1932

After a gruelling train journey, the puppy arrived at the Ueno residence in Shibuya district on 15 January 1924, where it was initially thought dead. According to Hachiko's biographer, Prof Mayumi Itoh, Ueno and his wife Yae nursed him back to health over the next six months.

Ueno named him Hachi, or eight in Japanese. Ko is an honorific bestowed by Ueno's students.

The long wait

Ueno took a train to work several times a week. He was accompanied to Shibuya station by his three dogs, including Hachiko. The trio would then wait there for his return in the evening.

On 21 May 1925, Ueno, then 53, died of a cerebral hemorrhage. Hachiko had been with him for just 16 months.

"While people were attending the wake, Hachi smelled Dr Ueno from the house and went inside the living room. He crawled under the coffin and refused to move," writes Prof Itoh.

Hachiko spent the next few months with different families outside Shibuya but eventually, in the summer of 1925, he ended up with Ueno's gardener Kikusaburo Kobayashi.

Having returned to the area where his late master lived, Hachiko soon resumed his daily commute to the station, rain or shine.

"In the evening, Hachi stood on four legs at the ticket gate and looked at each passenger as if he were looking for someone," writes Prof Itoh.

Station employees initially saw him as a nuisance. Yakitori vendors would pour water on him and little boys bullied and hit him.

However, he gained nationwide fame after Japanese daily Tokyo Asahi Shimbun wrote about him in October 1932.

The station received donations of food for Hachiko each day, while visitors came from far and wide to see him. Poems and haikus were written about him. A fundraising event in 1934 to make a statue of him reportedly drew a crowd of 3,000.

Hachiko's eventual death on 8 March 1935 made the front page of many newspapers. At his funeral, Buddhist monks offered prayers for him and dignitaries read eulogies. Thousands visited his statue in the following days.

Hachiko;s statue is a popular spot and often a place for political protests

In impoverished post-war Japan, a fundraising drive for a new statue of Hachiko even managed to raise 800,000 yen, an enormous sum at the time, worth about 4bn yen (£22m; $28m) today.

"In retrospect, I feel that he knew that Dr Ueno would not come back, but he kept waiting - Hachiko taught us the value of keeping faith in someone," wrote Takeshi Okamoto in a newspaper article in 1982. As a high school student, he had seen Hachiko at the station daily.

Remembering Hachiko

Every year on 8 April, a memorial service for Hachiko is held outside Shibuya Station. His statue is often decorated with scarves, Santa hats and, most recently, a surgical mask.

His mount is on display at the National Museum of Nature and Science in Tokyo. Some of his remains are interred at the Aoyama Cemetery, alongside Ueno and Yae. Statues of him have also been cast in Odate, Ueno's hometown Hisai, the University of Tokyo and Rhode Island, the American setting for the 2009 movie.

Odate also has a series of events lined up this year for his 100th birthday.

Will the world's most loyal dog still be celebrated a century from now? Prof Yano says yes because she believes the "heroism of Hachiko" is not defined by any particular period - rather it is timeless.

Mr Sakuraba is equally optimistic. "Even 100 years from now, this unconditional, devoted love will remain unchanged, and the story of Hachiko will live on forever."

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Researchers,” writes Giorgio Parisi, recipient of the 2021 Nobel Prize in Physics, “often pass by great discoveries without being able to grasp them.” A friend’s grandfather identified and then ignored a mould that killed bacteria, and so missed out on the discovery of penicillin. This story was told to Parisi in an attempt to comfort him for the morning in 1970 he’d spent with another hot-shot physicist, Gerard ’t Hooft, dancing around what in hindsight was a perfectly obvious application of some particle-accelerator findings. Having teetered on the edges of quantum chromodynamics, they walked on by; decades would pass before either man got another stab at the Nobel. “Ideas are often like boomerangs,” Parisi explains, and you can hear the sigh in his voice, “they start out moving in one direction but end up going in another.”

In a Flight of Starlings is the latest addition to an evergreen genre: the scientific confessional. Read this, and you will get at least a frisson of what a top-flight career in physics might feel like. There’s much here that is charming and comfortable: an eminent man sharing tales of a bygone era. Parisi began his first year of undergraduate physics in November 1966, at Sapienza University, in Rome, when computer analysis involved lugging about (and sometimes dropping) yard-long drawers of punched cards.

The book’s title refers to Parisi’s efforts to compute the murmurations of starlings. He’s also trying to work out how many solid spheres of different sizes will fit into a box. There’s a goofiness to these pet projects that belies their significance. The techniques developed to follow thousands of starlings through three dimensions of space and one of time bear a close resemblance to those used to solve statistical physics problems. And fitting marbles in a box? That’s a classic problem in information theory.

The implications of Parisi’s work emerge slowly. The reader, who might, in all honesty, be touched now and again by boredom, sits up straighter once the threads begin to braid. Physics for the longest time could not handle complexity. Galileo’s model of the physical world did not include friction, not because friction was any sort of mystery, but because the mathematics of his day couldn’t handle it.

Armed with better mathematics and computational tools, physics can now study phenomena that Galileo could never have imagined would be part of physics. For instance, the melting of ice, and the boiling of water: phenomena that, from the point of view of physics, are very strange indeed. Coming up with models that explain the phase transitions of more complex and disordered materials, such as glass and pitch, is something Parisi has been working on, on and off, since the middle of the 1990s.

Efforts to model more and more of the world are nothing new, but once rare successes now tumble in upon the field at a dizzying rate, almost as though physics has undergone its own phase transition. This, Parisi says, is because once two systems in different fields of physics can be described by the same mathematical structure, “a rapid advancement of knowledge takes place in which the two fields cross-fertilise”.

This has clearly happened in Parisi’s own specialism. The mathematics of disorder apply whether you’re describing why some particles try to spin in opposite directions, or why certain people sell shares that others are buying, or what happens when some dinner guests want to sit as far away from other guests as possible. Phase transitions eloquently connect the visible and quantum worlds. Not that such connections are particularly hard to make. Once you know the physics, quantum phenomena are easy to spot. Ever wondered at a rainbow?

“Much becomes obvious in ­hindsight,” Parisi writes. “Yet it is striking how in both physics and mathematics there is a lack of ­proportion between the effort needed to understand something for the first time and the simplicity and naturalness of the solution once all the required stages have been completed.” The murmurations of airborne starlings are ­created when each bird in the flock pays attention to the movements of its nearest neighbour. Obvious, no? But as Parisi in his charming way makes clear, whenever something in this world seems obvious to us, it is likely because we are perched, knowingly or not, on the shoulders of giants.

In a Flight of Starlings: The Wonder of Complex Systems is published by Allen Lane at £20. To order your copy for £16.99 call 0844 871 1514 or visit books.telegraph.co.uk

Simon Ings is the author of Stalin and the Scientists: A History of Triumph and Tragedy, 1905-1953 (Faber, £12.99)

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The suicide rates among young people aged 10-29 and elderly people aged 70-79 were particularly concerning, the prevention center Samaritans of Singapore (SOS) said in its annual press release containing statistics on the issue.

A total of 476 individuals killed themselves in 2022, "the highest recorded suicide deaths since 2000", up from 378 the year before, the SOS release said.

"Seeing the unprecedented rise in suicide numbers in Singapore is profoundly heartbreaking," veteran psychiatrist and mental health consultant Jared Ng was quoted as saying.

"This increase paints a picture of the unseen mental distress permeating our society, especially among our youths and the elderly.

"It is crucial that we remain vigilant to the pressing issues that continue to heavily impact mental health, such as social isolation and loneliness."

Suicide "remained the leading cause of death for youths aged 10-29 for the fourth consecutive year", accounting for 33.6 percent of all deaths within the age group, the release said.

A total of 125 individuals from that age bracket took their own lives in 2022, up 11.6 percent from 112 the previous year.

Globally, suicide is the fourth leading cause of death among those aged 15-29, according to the World Health Organization (WHO).

In Singapore, the number of people aged 70-79 who took their own lives surged to 48 last year, a 60 percent increase from 30 in 2021, according to SOS.

The city-state, which has one of the world's lowest fertility rates, has a rapidly aging population, with one in four Singaporeans projected to be 65 or older by 2030, up from one in six three years ago.

SOS chief executive Gasper Tan said suicide was a "complex issue influenced by various factors, including mental health challenges, social pressures, and economic uncertainties".

"We recognize the urgency of the situation, and are committed to continue taking proactive steps to address the rising suicide numbers and provide support to those in need," he added.

More than 700,000 people around the world die by suicide every year, the WHO says.

© 2023 AFP

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This is the conclusion of studies on COVID-19 presented at the 9th BRAINN Congress organized by the Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), a Research, Innovation and Dissemination Center (RIDC), held April 17–19 in São Paulo, Brazil.

"Before the pandemic, Brazil was already considered one of the most anxious countries in the world, with 9% of the population reporting symptoms. Now we find higher levels of anxiety and depression in people who test positive for COVID-19," said Clarissa Yasuda, a professor at UNICAMP's Medical School (FCM) and a researcher affiliated with BRAINN.

One of the presentations at the conference reported the findings of an analysis of MRI scans performed three months after infection and showing gray matter atrophy and cerebral hyperconnectivity in patients with long COVID.

The duration of these alterations and their significance from the biological standpoint are unknown, but the results suggest cognitive dysfunction, which the scientific literature shows to be highly affected by anxiety and depression, according to an article on the study published in a special supplement of the journal Neurology by Beatriz Amorim da Costa, an undergraduate at FCM-UNICAMP, and collaborators.

"Our findings serve as an alert to the extent of the pandemic's possible consequences," said Yasuda, last author of the article.

Gray matter atrophy appeared in MRI scans of the brains of patients infected by four different strains of SARS-CoV-2 (alpha, delta, gamma and zeta), according to Lucas Scárdua Silva in another article published in the same issue of Neurology. This study, which Yasuda also supervised, detected frontal lobe and limbic system gray matter atrophy in subjects infected by all four strains.

Ítalo Karmann Aventurato presented the results of a study showing verbal memory impairment in patients infected by all four strains. The study was also led by Yasuda and reported in the same journal.

Economic impact

The impact of long COVID on work capacity was the focus of a presentation by Gabriel Monteiro Salvador, who had a scientific initiation scholarship from FAPESP. Persistent neuropsychiatric symptoms such as somnolence, fatigue, anxiety and depression correlated directly with impaired work capacity in COVID-19 survivors, he said. The study, also overseen by Yasuda, is available in the same issue of Neurology.

Initially, a group of bank workers with similar characteristics in terms of job description, routine and schooling answered a questionnaire called the Work Ability Index (WAI), designed to arrive at an assessment of problems relating mainly to memory and cognition. In a follow-up assessment some months later, 62.5% of the participants still had reduced WAI scores.

"The economic impact of these people's health problems is evident, underscoring the urgent need for specific treatment to reduce the loss to both the individuals concerned and society as a whole," Salvador said.

Quantifying fatigue in practice

Fatigue is one of the symptoms most frequently reported by patients with long COVID, but the term is typically generic and lacks a clear definition. To quantify fatigue, researchers at UNICAMP's Center for Biomedical Engineering (CEB) led by Leonardo Elias, a professor at the School of Electrical and Computer Engineering (FEEC-UNICAMP), developed a set of tests to measure muscle contraction and force, neuromuscular function, hand muscle fatigability and manual dexterity.

The participants in the experiment were asked to perform a number of tasks, during which index finger abduction force and first interosseous dorsal muscle contraction force were measured with sensors and electromyography, a technique for recording the electrical activity produced by skeletal muscles. They were also submitted to the Nine Hole Peg Test, a standardized assessment used to measure finger dexterity.

Despite limitations such as the small number of participants and the possible influence of anxiety and depression symptoms, the study showed that motor skills may be impaired in patients with symptoms of fatigue due to long COVID. For example, motor unit force-frequency relationships were abnormal in reaction tasks, although reaction time was preserved. In the Nine Hole Peg Test, the patients underperformed with the dominant hand compared with the control group.

"The possible explanations for these results include increased intercortical inhibition [a neurophysiological process in which the activity of neurons in the cortex is reduced] and GABAergic pathway dysfunction [impairing regulation of cognitive and emotional processing], alterations in executive functions [cognitive skills relating to control of actions, emotions and thoughts] and greater perceived fatigue," Elias said.

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Like regular flies, muscae volitantes are rather pesky, so it's not surprising that people want to banish them. A recent article in the Mirror, Eye floaters: What causes them and how to get rid of them naturally, claims to have a solution.

Sarah Brewer, a GP, is quoted in the article as saying that a supplement called Clearer, made by Theia Bio, is "a natural but effective solution to address annoying floaters." Despite the promise in the headline, Dr. Brewer does not talk about getting rid of floaters.

The Theia Bio website uses more precise language. It says, "Clearer contains a blend of antioxidants and antiglycation micronutrients that has been scientifically proven to reduce eye floater size and visual discomfort in around 70% of test subjects over six months."

Before we look at the feasibility of a supplement to "address" annoying floaters or reduce their size, let's look at what floaters are and why they occur.

The main reason floaters occur is age. With age, the vitreous—a clear, gel-like substance inside the eye—starts to thicken and shrink. Vitreous consists mostly of water, collagens and an acid called hyaluronan. Over time, the vitreous degenerates slightly and little clumps of collagen begin to form. Floaters are the shadows these clumps cast on the retina.

With age, it's normal for the vitreous to pull away from the back of the eye, a process called posterior vitreous detachment, and this causes more floaters.

Is it possible that vitamin supplements could affect the clumps and strands of collagen, to improve the vitreous? In 2022, researchers in Taiwan reported that taking high-dose mixed fruit enzyme supplements could reduce floaters, but it's not clear how they measured the number of floaters, so it is difficult to judge this study properly without more information.

Theia Bio, the company that Dr. Brewer was speaking in partnership with, shares a link to a study on its website as scientific proof that the Clearer supplement can "reduce eye floater size and visual discomfort." But floaters are tricky to measure because the vitreous is mobile. Every time you move your eyes, the vitreous opacities (the floating objects in the vitreous) move, and the floaters—the shadows the vitreous opacities cast—move too.

The vitreous clumps are 3D, not 2D, so catching them from different angles affects the measure you take and floaters appear bigger when they're closer to the front of your eye. The reduction in opacity size in the study is based on just 26 people who took the formulation, and opacity sizes were reported in a 2D measure (cm²).

This small trial does not convince me that floater size can be reduced with this dietary supplement.

What about other solutions?

There are a couple of medical ways to get rid of floaters. The most accepted is a procedure called vitrectomy, which surgically removes the vitreous. But this surgery poses risks to a person's vision far more significant than the floaters themselves.

Zapping floaters with a laser (known as a YAG laser) is another option, but not all experts agree that this is safe. Worryingly, several private companies offer this treatment as a good solution, even though there are reports of damage to various eye structures and glaucoma as a result.

Other "solutions" suggested online include intermittent fasting, temple massage and acupressure, as well as eye exercises. But there is no credible evidence for these.

There is some evidence that lifestyle factors can accelerate or decelerate aging in the eye more generally, which might affect the age you first notice floaters, or how large or troublesome they are. For example, eating lots of vegetables rich in carotenoids (spinach, broccoli, watermelon, pink grapefruit) and fatty fish containing omega-3, may help people at risk of age-related macular degeneration.

Emerging evidence also suggests that excessive exposure to blue light from mobile phones, tablet computers and LCD screens might also accelerate age-related eye changes. But while slowing aging in the eye would be great, it's not proof that it will stop people from getting floaters.

So what should you do if you find yourself troubled by floaters? Mostly, the best thing to do is ignore them. Over time, the brain adapts and we notice them much less.

You're more likely to get floaters if you are shortsighted, had cataract surgery, or if you've had eye inflammation (swelling). And you might have more floaters if you have diabetes, so glucose and diabetic control are important.

Occasionally, floaters can be signs of a serious condition. If you suddenly notice a lot of new floaters or flashes, or if a shadow or gray curtain comes down over your vision, this could indicate a retinal tear needing urgent surgery.

The verdict

Can supplements "address" collagen clumps in the vitreous? There is little evidence to support this at present.

Can supplements and lifestyle changes slow the aging process in the eye, delaying the onset of these age-related floaters? Possibly.

Dr. Brewer makes excellent recommendations about nutritious food, hydration and sleep—all great ways to maintain your health. It's doubtful that it will have a direct impact on floaters, but it's great health advice generally and might delay the aging processes in the eye by which they arrive.

Kawa Wong, the founder of Theia Bio, told The Conversation that his company "does not promise a cure for eye floaters; rather, it offers the best nutritional support for eye floater patients based on available scientific evidence."

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Diet-related disease—which includes obesity, heart attack, strokes, cancer, and dementia—is the leading cause of early death in the UK. Driving it is a set of industrially processed products that are sold as food, known formally as ultra-processed food (UPF).

This type of food is usually wrapped in plastic and has additives that you won’t find in a typical kitchen. In the US and the UK, we get on average 60 percent of our calories from UPF products like pizza, bread, breakfast cereals, biscuits, and nutritional drinks. They’re often sold as healthy options, but it’s just a way of turning our ill health into money. UPF is a byproduct of a complicated financial system that involves repurposing waste from animal food into human food.

To solve this problem, the first thing we need to do is include in the official UK guidance about nutrition the information that ultra-processed foods are associated with weight gain and diet-related diseases, and that the recommendation for people is to avoid these foods. Many countries like Brazil and France already do this.

Limiting the marketing of ultra-processed foods is essential. We need to learn the lessons from regulating the tobacco industry and stop predatory companies selling this food to people.

We also need to change the ultra-processed institutional food that we serve in hospitals, schools, and prisons. There is very good evidence that when feeding patients and staff in hospitals, real food is hugely beneficial.

There are also misconceptions we need to address. For instance, people who live with diet-related diseases, especially obesity, usually have a strong feeling of guilt, thinking they are the problem due to their own lack of willpower. Researchers now know this isn’t true. This food has been engineered to be addictive. We need to shift the blame away from the population.

Normally, we would blame the food companies and demand change from them. But when you speak to people in any of those companies it’s very clear that they are unable to change. Danone is the best example of this. Its previous CEO, Emmanuel Faber, tried to turn the company into a social enterprise by stopping the sale of ultra-processed food and increasing the environmental portfolio. The share price tanked, activist investors threw him out, and Danone had no option but to go back to its previous business model. All the big transnational food corporations are answerable to their owners. If we don’t understand this financial loop, we will keep shouting at companies that cannot change their business model. What we have to understand is that the responsibility lies with governments. They need a mandate from their population to change the regulations.

Another group of people whom we don’t criticize enough are the doctors, who have a very long history of partnering with transnational food corporations and supplement providers to mislead people. Most nutrition research is funded by the food industry and that’s clearly wrong.

Anyone who’s struggling with this as an individual should take their guilt and shame and transfer it outwardly to the corporations that are feeding us these addictive substances, to the governments doing nothing about it, and to the physicians and the social media personalities who keep telling us that this stuff is healthy. We need to end the conflict of interest between the industry and politicians, doctors and scientists. Only then can we really tackle the problem.

This article appears in the July/August 2023 edition of WIRED UK magazine.

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According to books, articles and social media posts, our urge for a quick dopamine hit is why we crave cookies and spend too much time on Instagram. If we keep giving in to these desires, the rationale goes, we’ll never be able to stop ourselves.

“We’ve transformed the world from a place of scarcity to a place of overwhelming abundance,” Dr. Anna Lembke, a Stanford psychiatrist, wrote in her best-selling book “Dopamine Nation.” Consequently, we’re all at risk for “compulsive overconsumption.”

A self-improvement trend often called “dopamine fasting” that emerged in 2019 revolves around abstaining from anything that causes the release of the chemical. The premise is that modern-day entertainments rewire the brain so that slower-paced pastimes are no longer pleasurable.

Videos tagged #dopamine, many claiming to teach viewers how to manipulate the brain chemical, have more than 700 million views on TikTok.

One influencer offers a “free list of things that numb dopamine” so that you can “reclaim control over your life!”

Parents are even advised to prevent children from experiencing spikes in dopamine (meaning not to let them play video games or eat junk food) lest the insatiable need for the neurotransmitter increase bad behavior.

Scientists who study dopamine say these concerns have been blown out of proportion. They “are not necessarily based on actual science of what we know about dopamine,” said Vijay Namboodiri, an assistant professor of neurology at the University of California, San Francisco.

Before you swear off dopamine — and the prospect of any joy in life — it’s important to understand the biggest misconceptions about the neurotransmitter and what the research shows.

Dopamine is not inherently good or bad.

The idea that dopamine produces feelings of pleasure came from early experiments in rodents, and later humans, that found the dopamine system was activated when animals encountered a reward. Food, sex, drugs and social interactions all set off releases of dopamine in the brain, suggesting the neurochemical is linked to any feel-good outcome.

But upon further study in the 1990s, scientists realized that dopamine is more closely related to the anticipation of a reward than to its receipt. Dopamine causes the wanting of something and the motivation to go and get it, not the enjoyment of it.

“What we think it maybe does is something like desire,” said Talia N. Lerner, an assistant professor of neuroscience at Northwestern University. “It teaches your brain how to predict your needs and try to align your behaviors with those needs.”

A neurochemical that controls desire can sound sinister, but pursuing rewards is not inherently a problem; it all depends on the context. Animals from honeybees to humans developed dopamine systems to motivate them to seek out food and sex in order to survive and procreate.

“It’s an important part of why we’re here today,” said Kent C. Berridge, a professor of psychology and neuroscience at the University of Michigan. “We wouldn’t have evolved and we wouldn’t have survived, our ancestors, without dopamine.”

Dopamine is also essential for learning. In this context, the key element that causes dopamine neurons to fire is surprise, regardless of whether the outcome is rewarding or disappointing.

“Dopamine tells you not when something is good or bad, per se, but when it’s better or worse than you expected it to be,” Dr. Lerner said. That surge of dopamine helps you update your expectations and potentially modify your behavior for the future.

A normal hit of dopamine isn’t going to rewire your brain.

Because of dopamine’s role in motivation and learning, the worry is that highly stimulating activities will hijack the neurotransmitter system, such that it no longer works for smaller, everyday rewards. For someone hooked on video games, the thinking goes, Monopoly might be less rewarding.

This concern is partly based in science. Prolonged use of drugs that cause huge surges in dopamine, like cocaine and amphetamine, can cause the brain to shut off some of the receptors that the neurochemical acts on. This so-called tolerance means that more of the drug is required to achieve the same high.

Because video games and pornography can be habit-forming, some researchers — including Dr. Lembke — have hypothesized that they might cause similar signs of tolerance in the brain. However, in an interview with The New York Times, she admitted that this theory is inferred from studies of stimulant drugs and that there isn’t currently evidence to back it up.

As a result, Dr. Berridge and others have critiqued the idea. One reason is that the amount of dopamine released in response to video games, pornography, social media and junk food is substantially lower than that released in response to addictive drugs.

And while, for some people, video games cause a greater dopamine response than board games do, that doesn’t mean the board game causes a smaller dopamine release than it used to, and it isn’t because of an inherent change in the dopamine system, Dr. Namboodiri said. It also doesn’t mean that video game lovers will never want to play board games again. The same goes for eating candy versus eating fruit or watching YouTube versus reading a book.

Taking a break from video games or social media can be a good idea if you want to spend more time on other pursuits. But that’s not because you need to reset your dopamine system, Dr. Namboodiri said. (There is reason to believe that our digital lives have shortened our attention spans, but that’s a different story.)

“If the advice that someone’s giving you about what you should do holds regardless of whether dopamine is in play, it’s probably useful advice,” Dr. Namboodiri said. But he noted that “as a field we are still pretty far from having a complete understanding” of dopamine and how to manipulate it in daily life.

Addiction is about more than dopamine.

Some rewarding behaviors can cause problems in people’s lives. Although activities like gambling, watching pornography and playing video games don’t stimulate as much dopamine release as drugs do, they can lead to patterns of behavior similar to those seen in substance use disorder — namely, continuing the activity despite severe negative consequences.

But that is the exception, not the rule. Most people are not losing their jobs or relationships or experiencing negative health impacts because of these activities. Roughly 2 to 3 percent of people who watch pornography report being addicted to the behavior. Similarly, 2 to 3 percent of people who play online games qualify as having internet gaming disorder.

“For some people, yes, this is a problem,” Dr. Berridge said. “It’s not a problem for most people. We can function in the world and enjoy this reward-rich world.” As with most things related to health, the key is moderation. You don’t have to deny yourself pleasure to be a good or healthy person.

And while dopamine is involved in addiction, compulsions to use drugs or masturbate are more complicated than a single neurotransmitter. “To say that it’s only dopamine is an oversimplification,” Dr. Lembke said.

In fact, experimental attempts to treat addiction by altering dopamine activity in the brain haven’t worked. These types of compulsive behaviors are also often accompanied by other mental illnesses or extreme stress during childhood.

“Unless you’re using a drug like cocaine, which is probably blanketly unhealthy, there’s not necessarily a healthy or unhealthy way to use dopamine,” Dr. Lerner said. “It’s just about learning. And you can always learn something good, you can always learn something bad.”

Or, as Dr. Berridge put it, “dopamine is our friend, not just our enemy.”

The post We Have a Dopamine Problem appeared first on New York Times.

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Scientists armed with a new computer model have taken a step closer to unlocking the mind-bending secrets of optical illusions that trick the brain into seeing the wrong colors when it's processing images.

"Simultaneous contrast illusions" are a wide-ranging group of deceptive illustrations that trick people into thinking specific parts of an image are different colors from one another, when in reality, they're the same color. The effect rests on the illustrator altering the brightness or color in the background, in order to alter our perception of objects in the foreground. For example, in the image above, the smaller bar in the middle of the image is a single gray color but appears to be a gradient of varying shades because the background is brighter at one end and darker at the other. Another example is the Munker-White illusion, displayed in the image below, in which 12 spheres appear red, purple and green but are actually the same shade of beige.

Scientists have broadly known why these illusions work for more than a century, but in all that time, experts haven't been able to agree on exactly how they trick the brain. There are two possible explanations. The first is that the illusion is created from the bottom up, starting with low-level neural activity that requires no previous exposure to this type of illusion. The second is top-down, meaning it requires higher brain functions and plays off what your brain has previously learned about the brightness and color of light over time.

In a new study, published June 15 in the journal Computational Biology, a pair of researchers used a new computer model that mimics human vision to try to settle the debate once and for all.

In this illusions, the spheres appear to be different colors but they are actually all the same shade of beige. (Image credit: David Novick)

The model, known as the "spatiochromatic bandwidth limited model," uses computer code to mimic how the network of brain cells, or neurons, that first receive data from the eyes starts to decipher an image before that data is sent to other, "higher-level" regions of the brain to be fully processed. The model breaks down the image into sections, measures each section's brightness and then coalesces those assessments into a single report that can be sent to the brain, similar to what happens with human vision.

The beauty of this model is that the code allows the individual sections to be processed only at the same speed as human neurons could feasibly assess them, so the model is restricted to match our own visual limitations, study co-author Jolyon Troscianko, a visual ecologist at the University of Exeter in the U.K., told Live Science. "This aspect of the model is particularly novel — no one seems to have considered the effect that limited bandwidth might have on visual processing," he added. Specifically, the new model takes into account how quickly neurons can "fire," or shoot a message to other neurons in their network.

The two smaller gray bars in this image are the same shade of gray but appear different because of where they are positioned between he white and black lines.

(Image credit: Jolyon Troscianko)

The researchers used their new model to analyze more than 50 simultaneous contrast illusions to see if the program would also mistakenly identify specific parts of the images as being different colors, as a human being would. (It is unclear exactly how many simultaneous contrast illusions exist, but there are likely hundreds, the report authors noted.)

During these experiments, the model was consistently fooled into identifying the wrong colors, Troscianko said. "My collaborator [Daniel Osorio] kept emailing me new illusions, saying that he didn't think it would work with this one," he added. "But to our surprise and delight, it generally predicted the illusion in almost all cases."

In this illusion, the yellow tiles on the left cube and the navy tiles on the right cube are actually the exact same shade of gray. (Image credit: Jolyon Troscianko)

Because the model is also "tricked" by these illusions without the equivalent complex processing power of the human brain, it suggests that neither higher-order visual processing nor past experiences are required for these illusions to work. This seems to confirm the bottom-up hypothesis that says only basic-level neural processing is responsible for the images' deception, the authors concluded.

"In essence, many illusions that were previously thought to rely on complex visual processing, or at least visual processing that requires feedback loops, can actually be explained with something as simple as a single layer of neurons," Troscianko said.

The results support similar findings from a 2020 study in the journal Vision Research. In that study, children who were born with cataracts but underwent successful cataract removal were fooled by the images shortly after regaining their sight, despite having no past visual experiences to provide context for the images.

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Perhaps no name is more recognizable in connection with The Manhattan Project than Robert Oppenheimer. Oppenheimer, a genius theoretical physicist, was the director of the Los Alamos Lab, where the first atomic bomb was developed.

(Credit:Jeffrey M. Frank/Shutterstock) replica nuclear weapon

With a high level of intelligence and curiosity that started in childhood, Oppenheimer was a polymath. His breadth of knowledge exceeded the realm of physics and included history, the arts, language and writing — among other areas.

1. Who Was Robert Oppenheimer?

Many people are familiar with Oppenheimer’s scientific achievements, but there are several interesting things about his life you may not know.
Young Oppenheimer

Oppenheimer came from an affluent family and grew up in Manhattan’s Upper West Side. His parents recognized his high level of intelligence and provided opportunities to advance his learning. One of the areas he took an interest in was the study of minerals, and at only 11 years old, Oppenheimer became the youngest member of the New York Mineralogical Club. He’d present his first scientific findings to this group a year later.

Later, while a student at Cambridge, he attempted to poison his tutor with a toxic laced apple. Oppenheimer became distressed when he perceived physicist Patrick Blackett as too demanding — pressuring him to devote more time to the lab and less to theoretical physics. Blackett did not eat the apple, and the matter was not pursued.

Oppenheimer in the McCarthy Era

Although there is no denying Oppenheimer’s service to the U.S. government, in 1954, the Atomic Energy Commission (AEC) held a hearing against him. Because some of his friends had communist leanings and his own outspoken opposition to the development of a hydrogen bomb, he wound up on the wrong side of the same agency he had previously advised.

His loyalty to the U.S. was questioned, and there were even suspicions that he was a spy for the Soviets. Eventually, he was declared not guilty of treason, but his security clearance was revoked, and his name was tarnished. In December 2022, the ruling was overturned, and he was completely exonerated.

2. Did Oppenheimer Win A Nobel Prize?

Although 18 Los Alamos scientists were awarded Nobel prizes, Oppenheimer was not one of them — despite being nominated three times, in 1946, 1951, and 1967. Nobody knows for sure why he was not selected for the Nobel Prize, although there are several theories. His published work may not have been considered important enough, as he never proved any noteworthy theory or made any major discovery.

Some scholars and scientists believe that the award committee did not want to select someone who helped create the atomic bomb. Lastly, Oppenheimer’s shifting scientific research interests resulted in a lack of focus and accomplishments in one area in which significant accomplishments would warrant a Nobel Prize.

3. Was Oppenheimer An Adulterer?

When Robert Oppenheimer met Kitty Harrison, she was still married to her third husband. She and Oppenheimer started an affair, and when she became pregnant, she temporarily moved to Nevada in order to obtain a quick divorce. The day after she was granted the divorce, she married Oppenheimer in 1940.

While married to Kitty, he reignited a relationship with his former girlfriend, psychiatrist and Communist party member, Jean Tatlock. His affair with her led to suspicions about his political loyalty. In 1944, She was found dead with her head submerged in her bathtub. While the official cause of death was suicide, there has been speculation that she may have been assassinated by intelligence agents connected to The Manhattan Project.

It is believed that he also had an affair with Ruth Tolman, the wife of a fellow Manhattan Project scientist. Tolman, who was 10 years older than Oppenheimer, was an accomplished psychologist.

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Now, research reveals it can stop transmission of a deadly disease spreading in the U.S. for the first time in 20 years: malaria.

A team from FIU's Herbert Wertheim College of Medicine developed arsinothricin (AST) to combat the rise of antibiotic-resistant bacteria. Lab tests proved AST effectively defeated the most notorious, including E. coli and Mycobacteria, which cause tuberculosis.

Collaborating with malaria researchers in the College of Arts, Sciences & Education, they've recently also found AST prevents Plasmodium falciparum, the parasite that causes malaria, from infecting mosquitoes—unlike other current antimalarial drugs. The discovery, recently published in Microorganisms, paves the way for AST to one day be developed into a more effective antimalarial drug for humans.

"Current antimalarials don't completely stop transmission, meaning patients can continue to infect mosquitoes before they recover," said lead author of the study Masafumi Yoshinaga, associate professor of Cellular Biology & Pharmacology. "Developing new potent multi-stage drugs is imperative to ensure malaria elimination and eradication. We found AST is a promising lead compound for developing a new class of potent multi-stage antimalarials."

While AST contains arsenic—an incredibly toxic, deadly poison—it is not pure arsenic. In fact, since the early 1900s, arsenic-based medications have been used to safely treat and prevent many diseases. When FIU researchers tested AST on liver, kidney and intestinal cells, AST targeted the malaria parasite lurking in human cells but didn't damage the cells themselves.

An estimated 240 million malaria cases are reported worldwide every year. While the majority occur in Africa, malaria can still happen in the U.S. Recently, the U.S. Centers for Disease Control and Prevention issued a health alert about several locally acquired malaria infections in Florida and Texas, marking the first time it has spread in the United States since 2003.

Only mosquitoes transmit malaria. According to Jun Li, associate professor of biological sciences, Biomolecular Sciences Institute researcher and one of the study's authors, malaria spreads when a mosquito bites someone with malaria, and the parasites in the blood infect the mosquitoes. Ten days later, infected mosquitoes can bite another person and transmit the disease to them. Using AST to prevent parasites from spreading to mosquitoes breaks the malaria life cycle.

The team has received a U.S. patent for the chemical synthesis of, and methods of using AST. But before AST can become a drug—a sometimes lengthy, expensive process—the team will continue their research investigating how it enters human red blood cells, where it can be even more effective against the parasite.

"What's exciting about our research is it demonstrates how chemically different AST is from other drugs and that gets us even closer to drugs that are more effective," said Barry P. Rosen, distinguished university professor and a member of the research team. "We have a long way to go before we have a drug that goes to market, but this foundational work paves the way toward that goal."

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Some people who sought jobs at billionaire Bill Gates’s private office described going through an extensive screening process that included being questioned by a security firm about their sexual histories, past drug use and other parts of their private lives that might indicate they were vulnerable to blackmail.

Some female job candidates were asked whether they ever had extramarital affairs, what kind of pornography they preferred or if they had nude photographs of themselves on their phones, according to the candidates and people familiar with the hiring process. While it couldn’t be determined whether any men were asked such questions, none who spoke to The Wall Street Journal said they had.  

Female candidates sometimes were asked whether they had ever “danced for dollars,” some of the people said. One of the candidates was asked whether she had ever contracted a sexually transmitted disease, according to the candidate.

A spokeswoman for Gates said his private office, Gates Ventures, hasn’t heard about such questions being asked during background checks done by third-party contractors. “This line of questioning would be unacceptable and a violation of Gates Ventures’ agreement with the contractor” who must comply with pre-employment screening laws, she said.

The people said the screenings were conducted in recent years by a security consulting firm called Concentric Advisors, and the interviewers were ultimately trying to find any information that had the potential to be used to compromise or blackmail individuals who would be working closely with one of the world’s richest men.

Concentric said its protocols comply with applicable laws.

Gates himself also has had multiple extramarital affairs and had meetings with Jeffrey Epstein, a convicted sex offender, the Journal has reported. Gates has said it was a mistake to associate with Epstein.

Employment lawyers and security consultants said the process these people described could run afoul of state and federal employment discrimination laws. For certain high-security government roles, such questions may be more acceptable, they said.

Carol Miaskoff, legal counsel of the federal Equal Employment Opportunity Commission, said any questions about a candidate’s health or psychiatric history before a job offer “is just flat out prohibited by the federal Americans With Disabilities Act” regardless of who does the questioning during the application process.

Questions related to past illegal drug use could violate the same law since they may reveal an addiction, which is considered a disability, she said. Instead, Miaskoff said an employer can ask if a candidate is currently using drugs illegally or get consent for a drug test.

“There’s not a black letter law prohibition on asking questions related to sex,” Miaskoff said, but “getting the information and taking some adverse action with that information” such as rejecting the candidate could lay the basis for a legal challenge.

The Gates spokeswoman said Gates Ventures, which was previously known as bgC3, follows careful due diligence when hiring staff and that it works with contractors to perform industry-standard pre-employment screenings for men and women. She said it requires all vendors to operate in compliance with state and federal laws and regulations.

“We have never received information from any vendor or interviewee in our 15+ year history that inappropriate questions were asked during the screening process,” she said in a statement. “We can confirm, that after a comprehensive review of our records, no employment offer has ever been rescinded based on information of this nature.”

Concentric CEO Mike LeFever said that the company provides industry-standard background checks for hundreds of companies and its pre-employment interview protocol, which is identical for men and women, is compliant with laws in each state and nation where it provides services.

Asked how questions about sexual or medical histories comply with laws, a spokesman for Concentric denied it initiated such questions and said such information can be volunteered by job candidates when asked about public records. The Concentric spokesman said the company doesn’t provide hiring recommendations as part of its security-screening business.

The security screening involves “assessing a candidate’s truthfulness and vulnerability to blackmail, which often starts with voluntary statements by the candidate with follow-up questions by company interviewers,” the spokesman said. Not all information discussed in a Concentric security screening is included in the reports it provides to clients, he said.

Job candidates disputed Concentric’s characterization, saying they were asked about sensitive information and didn’t volunteer it. They also said they were informed that their job offers were conditional on passing the assessments. Documents also are at odds with the contention that the screening process wasn’t for employment purposes.

Concentric says on its website it has worked with private family offices for almost two decades. It cites work including pre-employment background checks and due-diligence investigations.

A consent form, reviewed by the Journal, said a behavioral assessment by a Concentric professional would be used to “assess suitability for employment” by Gates’s private office and would include drug and alcohol history as well as past medical and psychiatric history as it relates to the job.

The form, requiring a signature from the job candidate, gave permission to disclose the results from the assessment to Gates’s private office, including “highly sensitive information,” and “does not allow for the re-disclosure of sexually transmitted diseases,” the document shows.

Some people who worked for Gates’s private office said they didn’t undergo such questioning.

Gates himself was investigated in 2019 by Microsoft board members over allegations of a past sexual relationship with a Microsoft employee. Epstein appeared to attempt to blackmail Gates in 2017 over a different affair with a Russian bridge player, the Journal has reported. Gates’s spokespeople have said that he had a consensual relationship with the Microsoft employee about two decades ago, and that Epstein tried unsuccessfully to leverage the past relationship with the Russian woman.

The Microsoft co-founder has hundreds of people who work for several entities he controls, including Gates Ventures, private aircraft, horse stables and a company that oversees household staff and security. These workers are hired directly for these entities and they aren’t employees of the Bill & Melinda Gates Foundation or Microsoft.

Concentric’s headquarters are in the same lakefront office park in Kirkland, Wash., as Gates Ventures. Photo: Pictometry

Concentric describes itself as a risk-management firm that has several former Central Intelligence Agency and Federal Bureau of Investigation officials on its staff. It has worked with private family offices for almost two decades, providing pre-employment checks and mitigating risks posed by individuals with “potentially nefarious motives,” according to its website.

Concentric’s headquarters are in the same lakefront office park in Kirkland, Wash., as Gates Ventures.

Informally, Gates employees would warn job candidates that a “former CIA agent” would be drilling into medical information, past drug use and relationships, including former sexual partners, some people said.

Employment lawyers said questions about a job candidate’s medical or psychiatric history are illegal, even if part of a security screening for a private office. If a job candidate signs a consent form, it doesn’t make the questions legal, they said.

Questions about a candidate’s sexual history or preferences are “deeply offensive and it has nothing I can conceive of whether a person can do a job,” said Lindsay Halm, a Seattle-based employment lawyer. “I suppose if you’re working at a sex toy store or an adult film store where you might conceivably have a job-related question about that.”

A typical pre-employment background investigation includes an examination of public records and databases, confirmation of resume content and reference checks in addition to an interview confirming job qualification details, the applicant’s background and whether the candidate would be a good fit for the company, said Daniel Karson, a security industry veteran and former executive for business investigations firm Kroll Associates.

“I have never encountered that kind of questioning in a pre-employment background investigation in the private sector,” he said, referring to the questions related to sexual or medical history.

Write to Khadeeja Safdar at khadeeja.safdar@wsj.com and Emily Glazer at Emily.Glazer@wsj.com

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Study authors stress that the absolute risk difference was small, but at the same time, this was the largest trial of its kind to date. Further evaluations are no doubt necessary, especially among those taking statins or other cardiovascular disease drugs.

Cardiovascular disease (CVD) is a general term encompassing all conditions affecting the heart or blood vessels and is one of the main causes of death globally. CVD events like heart attacks and strokes are projected to increase as populations continue to live longer and chronic diseases become more and more common.

Prior observational studies have consistently noted a link connecting vitamin D levels and CVD risk, but thus far randomized controlled trials have yielded no evidence that vitamin D supplements prevent cardiovascular events — possibly because of the differences in trial design that can influence results.

To address this, the research team in Australia assessed if supplementing older adults with monthly doses of vitamin D would alter the rate of major cardiovascular events. This D-Health Trial was carried out between 2014 and 2020 and included 21,315 Australians (ages 60-84). Participants received one capsule of either 60,000 IU vitamin D (10,662 people) or a placebo (10,653 people) to take orally at the beginning of each month for up to five years.

Those with a history of high calcium levels (hypercalcemia), overactive thyroid (hyperparathyroidism), kidney stones, soft bones (osteomalacia), sarcoidosis, an inflammatory disease, or anyone already taking more than 500 IU/day vitamin D were excluded from the experiment.

Next, the research team made use of data covering hospital admissions and deaths to identify major cardiovascular events like heart attacks, strokes, and coronary revascularization (a treatment to restore normal blood flow to the heart).

Average treatment duration lasted five years, with over 80 percent reporting taking at least 80 percent of their tablets. Over the course of the trial, 1,336 participants experienced a major cardiovascular event (6.6% in the placebo group, 6% in the vitamin D group). Meanwhile, rate of major cardiovascular events was nine percent lower in the vitamin D cohort compared to the placebo group (equivalent to 5.8 fewer events per 1,000 people).

Heart attack (-19%) and coronary revascularization (-11%) rates were lower in the vitamin D group, but the team did not note any differences in the rate of stroke between the two cohorts. Notably, there was some indication of a stronger effect on those using statins or other cardiovascular drugs at the beginning of the trial. However, researchers clarify those findings were not statistically significant.

All in all, it is estimated that 172 people would need to take monthly vitamin D supplements to stop one major cardiovascular event from occurring.

In conclusion, study authors acknowledge a small underestimation of events may have occurred, and these findings may not apply to other populations, especially populations in which a higher proportion of people are vitamin D deficient. However, this project was still a very large trial with extremely high retention and adherence, as well as a near-complete dataset covering cardiovascular events and mortality outcomes. Researchers believe their findings suggest vitamin D supplementation may reduce the risk of major cardiovascular events.

“This protective effect could be more marked in those taking statins or other cardiovascular drugs at baseline,” researchers add in a media release, suggesting further evaluation is warranted to help to clarify this issue.

“In the meantime, these findings suggest that conclusions that vitamin D supplementation does not alter risk of cardiovascular disease are premature,” the study authors conclude.

The study is published in The BMJ.

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There’s much that we take for granted in our modern world. For example, have you ever considered the history of lenses, and how they have extended our view of the universe? The development of this subtle technology not only allows us to examine the very small or to peer into the vastness of space, but they also play an important role in our everyday lives, such as in our cameras, on cinema projectors, or simply as the glass in our spectacles. Lenses are extremely valuable, and they have played an important role in the History of Science, not least in the development of modern telescopes.

The birth of the telescope

Telescopes are arguably one of the most iconic scientific instruments ever invented. Few other objects are so easily identifiable, both in appearance and in terms of their intended use. Telescopes – those wondrous optical tubes – have changed the way we understand our world and its place in the cosmos. To be sure, their development would not have been possible without far older advances in lens technologies and accompanying theories of optics, but this deeply fascinating and detailed history is too expansive to be captured here. Nevertheless, we can start to think about the story of telescopes, an instrument brought into existence by this history, as starting in the late 16th and early 17th centuries. 

As with other early technologies involving lenses, we are not certain who their first inventor was, but we do know that in 1608, a Dutch spectacle maker called Hans Lipperhey announced a new instrument that used lenses to make distant objects appear closer. This seems to be the first evidence of a telescope in historical record. Lipperhey applied for a patent for his new device, which circulated across Europe allowing other early “scientists” to experiment with their own versions. One such experimenter was the Italian polymath Galileo Galilei who heard about Lipperhey’s invention while in Venice in June 1609.

The early history of the telescope is tightly bound with the career of Galileo, whose work had lasting consequences for our understanding of the universe. Often remembered as a heroic figure who challenged the established worldview of his day, Galileo’s story is actually an important example of how concurrent developments in scientific thinking, technological development, and networks of knowledge come together. 

Following Lipperhey’s example, Galileo decided to make his own telescope and to turn its vision-enhancing powers to the heavens. Although he was not the only astronomer to do this at the time, the success of his telescope won him a lifetime lectureship. He then set about refining his instrument. The original telescope, like Lipperhey’s, offered three times magnification, but his subsequent versions first offered eight times and eventually 30 times magnification. This provided unprecedented views of celestial objects and changed everything. Ultimately, Galileo was not alone in utilizing telescopes for this purpose, but he was very quick at publishing his results and understanding their implications.

 His most crucial observations included the revelation that, contrary to Aristotelian principles, the Moon was not a smooth sphere but a rough textured object like the Earth, with its own depressions and mountains. He also identified the existence of four previously unknown moons orbiting Jupiter, which was the first-time objects had ever been seen to orbit another body besides the Earth or Sun. Then there were the phases of Venus, which could not be accommodated by the traditional Earth-centric model of the universe. 

This led Galileo to champion the Copernican heliocentric model, which had been published by the Polish polymath in 1543. Like a few others at the time, Galileo also observed sunspots on the surface of the Sun and interpreted them as blemishes that moved due to its rotation – this was another nail in the coffin for the Aristotelian view of a perfect unchanging cosmos.  

 Refining things   

In 1611, Johannes Kepler, inspired by Lipperhey and Galileo’s work, designed and built his own telescope – the famous Keplerian Telescope. This device was developed independently of its predecessor’s designs and used convex lenses that allowed viewers to see far larger fields of view (though it also inverted the image). Kepler’s telescope is noteworthy because it achieved a much greater level of magnification than Galileo’s versions, which enabled him to not only confirm many of the Italian’s observations but to make his own. He recorded these in his Conversation with the Starry Messenger. 

Today, Kepler is remembered for his contributions to astronomy, but he was also extremely influential in the field of optics. In fact, his groundbreaking Astronomiae Pars Optica has earned him the title of “Father of Modern Optics”. His work would go on to have important implications for subsequent discoveries by individuals like Isaac Newton, who continued to develop and improve these early telescopes as well as the laws of optics that underpinned them. 

 Bigger is better, right?

One of Newton’s important contributions to the development of telescopes had significant implications for traditional refraction devices. Instead of using lenses, Newtonian Telescopes (the first of which was built in 1668) relied on mirrors instead. Essentially, a large concave mirror would focus light onto a smaller one, which then projected the image onto an eyepiece on the side of the instrument. This alteration overcame a persistent issue that occurred in traditional refraction telescopes, what is known as chromatic aberration – an effect that occurs when a lens cannot correctly refract all the wavelengths of color in the same point.  

To be sure, Newton was not the first person to consider reflective telescopes, but his version had some important advantages. It was cheaper, did not produce the chromatic aberration, and was both easier to put together and to carry. However, Newton’s view that reflective telescopes were the only way around the aberration issues was soon proven wrong by Chester Moore Hall, who, in 1729, developed a new lens that consisted of two types of glass that were cemented together. This modification overcame the same issue and proved that refraction telescopes were still viable. 

Now, a kind of arms race kicked off within astronomy and telescope manufacturing communities, where individuals competed to create bigger and bigger versions of these devices. One of the most famous was William Herschel’s 12-meter (40-foot) reflector telescope that was built in 1789. Over the next century, other larger devices were built until 1897, when the Yerkes Observatory in Wisconsin, US, opened with a massive 100-centimeter (40-inch) refractive lens that was, at the time, the largest of its kind in the world. This telescope is very much still in use today, but eventually, as we moved into the 20th century, the race for bigger and better telescopes was largely won by reflective versions. 

Today, most telescopes used within observatories or on space stations rely on mirrors rather than lenses and the race to build the biggest devices is very much over. Nevertheless, the significant advances made in optics and accompanying lens-making practices that were developed and honed in previous centuries have provided the grounds upon which our current efforts to explore the universe rest.  

All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.

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In 2008, a fruit fly known as the spotted-wing drosophila made its way from Southeast Asia to the continental US, likely hitching a ride on fruit shipments. First detected in California raspberry fields, the insect rapidly spread to other states.

Unlike the common fruit fly, which is attracted to rotting food, spotted-wing drosophila prefers ripening, healthy fruit. Using a serrated, tubelike organ, the females slice through fruit skin and deposit their eggs inside. When the eggs hatch, the emerging larvae destroy the crop. The invasive pests cause hundreds of millions of dollars in damage each year. To control them, growers rely on pesticides that kill insects indiscriminately, including both pests and helpful bugs. But scientists are working on new solutions that could one day replace—or at least limit—the need for spraying chemicals.

In greenhouses in Oregon last month, researchers with the US Department of Agriculture began testing one such approach: sterilized male flies. The gene-edited bugs, made by St. Louis–based biotech company Agragene, are meant to suppress wild fly populations. The idea is that if they were to be released into the environment, the sterilized males would mate with wild females, resulting in a fertility dead end. “We see this technology as being able to provide healthier fruit and vegetables without doing a lot of harm to the environment,” says Agragene CEO Bryan Witherbee.

Scientists at the company used the DNA editing tool Crispr to knock out two essential genes in fly embryos—one involved in male reproduction and another with female development. As a result, only sterile males hatch while the females die. “You don’t want to release females into the population, because those are the ones that are doing the damage,” says Stephanie Gamez, director of research and development at Agragene.

But before the company can release any gene-edited insects into the open, it first has to test them in contained greenhouses. Working with government researchers, and with permission from the USDA, the company is testing how well the edited males can bring down the populations of unedited flies in greenhouse conditions and prevent damage to blueberries being grown there. The experiments will last two to three months.

The company is now applying to the agency to do field tests next year. Eventually, Agragene’s plan is to sell small cardboard boxes containing sterile male pupae—the stage right before flies turn into adults. At this phase, the pupae are cocooned and immobile, making them easy to transport to farms. (Witherbee says the company tried shipping live adult flies, but some insects died in the process.) Boxes would be placed in fields, and when the adult flies emerge, they’ll seek out females.

Witherbee thinks a ratio of four or five sterilized males to every wild one will be needed to quash a population, and the severity of a field’s infestation will determine how many insects to release. Since the males are sterile, no offspring are produced when they mate with females. Spotted-wing drosophila only live a few weeks, so once the first generation dies, repeated releases of edited males would be needed to keep populations down. Witherbee says the company will start with weekly releases in the greenhouse experiments, but in the field, multiple releases in a shorter period of time may be needed.

“If you release enough males over a long enough period of time, you can eliminate the pest,” says Omar Akbari, a professor of cell and developmental biology at the University of California, San Diego, who originally developed the gene-editing technique for flies and licensed it to Agragene.

Using sterilization as a way to control insect pests isn’t a new idea. Since the 1950s, the US government has used it to tamp down screwworms, parasitic flies that feed on the flesh of livestock. Sterilized male screwworms are released to mate with females, which lay eggs that don’t hatch. This technique has led to their eradication in North and Central America. But those male insects are made sterile with radiation rather than genetic engineering. The downside is that high levels of radiation impair their ability to reproduce, meaning dozens of insects are often released for every wild one.

Meanwhile, researchers at North Carolina State University are developing an alternative control method that wouldn’t require repeated releases. In the lab, they used a technique called a gene drive to make female offspring unable to reproduce. Gene drives are designed to preferentially spread or “drive” certain genetic traits throughout a population, overruling the rules of heredity. 

In a paper published earlier this month, entomologist Max Scott and his team described using Crispr to inactivate a region of the doublesex gene, which is required for female sexual development. The researchers injected Crispr into fly embryos, along with a fluorescent protein so they could track which flies ended up with the desired change.

When the flies matured, the researchers mated the engineered insects with wild ones that didn’t have the mutated doublesex gene. Normally, about 50 percent of offspring would be expected to inherit the change. But with the gene drive, 94 to 99 percent of the flies’ offspring ended up with it. Females that inherited the mutated gene were sterile and unable to lay eggs. But male offspring, which also carry the change, remain fertile. Unlike Agragene’s approach, the males go on to breed and pass on the trait to subsequent generations. This allows the gene to continue spreading—and knocking out future generations of flies—without the need to release more insects.

“If we're trying to do population control, you really want to target a gene that's required for female reproduction, because it's the female that is producing the next generation,” Scott says.

The researchers used mathematical modeling to predict how well the gene drive system would suppress populations of flies kept in laboratory cages, and found that releasing one modified fly for every four wild ones could tank populations within eight to 10 generations. (Each generation lasts about two weeks, so crashing a lab population could take around 20 weeks.) Now the team is conducting experiments using cages of real gene-edited flies to learn whether the gene drive will suppress their numbers as the modeling predicts.

Researchers elsewhere are developing gene drives as a way to control disease-carrying mosquitoes, but none of these insects have been released yet in the wild. “There are a lot of risks associated with it, because it’s a technology that you can’t control once you release it,” says Akbari, whose lab has also worked on gene drives for spotted-wing drosophila. One risk is the possibility of spillover: If the target species mates with a closely related one, it could transfer the gene drive to a native or valued species.

And there’s a chance that the gene drive could stop working. Crispr works by recognizing a specific site in the genome. Any flies in the wild that have natural variations at this site wouldn’t be affected by the gene drive. “It’s one thing to work in a lab where there’s probably not a lot of genetic variation within your lab population,” Scott says. “But if you go out into the field, you’re dealing with huge populations and a lot of genetic variation.”

Hannah Burrack, an ecologist at Michigan State University who works on pest management, says the gene drive work is promising, but it’s far from being deployed by farmers. US regulations on gene drives are unclear, and scientists agree that work in this area should proceed cautiously. Still, she sees certain advantages: “The promise that Crispr has is that instead of having to overwhelm the population, you could potentially release small numbers of flies and rely on the deleterious gene to move through the population.”

She says the sterilized male approach would likely require large numbers of released flies, so it may not be practical for an individual farmer to do. Instead, she thinks repeated releases of gene-edited males will probably need to be done by a large group of growers or a government.

One concern with both approaches is how eradicating the fly might affect other species in their surrounding environment. For example, would getting rid of these flies deprive another animal of a food source or allow for the rise of other nuisance species?

Since the spotted-wing drosophila is invasive and arrived in the US fairly recently, Burrack thinks the ecological impact of wiping them out would be minimal. “It becomes a risk-benefit comparison,” she says. “We’d be comparing the presumably small risks associated with reducing the abundance of this invasive species from the environment with the risks associated with the status quo management right now, which is more pesticide use.”

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