MIT News has an announcement: The boiling of water or other fluids is an energy-intensive step at the heart of a wide range of industrial processes, including most electricity generating plants, many chemical production systems, and even cooling systems for electronics. Improving the efficiency of systems that heat and evaporate water could significantly reduce their energy use. Now, researchers at MIT have found a way to do just that, with a specially tailored surface treatment for the materials used in these systems. The improved efficiency comes from a combination of three different kinds of surface modifications, at different size scales. The new findings are described in the journal Advanced Materials in a paper by recent MIT graduate Youngsup Song PhD '21, Ford Professor of Engineering Evelyn Wang, and four others at MIT..... "If we have lots of bubbles on the boiling surface, that means boiling is very efficient, but if we have too many bubbles on the surface, they can coalesce together, which can form a vapor film over the boiling surface," Song says. That film introduces resistance to the heat transfer from the hot surface to the water. "If we have vapor in between the surface and water, that prevents the heat transfer efficiency and lowers the critical heat flux value," he says.... Adding a series of microscale cavities, or dents, to a surface is a way of controlling the way bubbles form on that surface, keeping them effectively pinned to the locations of the dents and preventing them from spreading out into a heat-resisting film... In these experiments, the cavities were made in the centers of a series of pillars on the material's surface. These pillars, combined with nanostructures, promote wicking of liquid from the base to their tops, and this enhances the boiling process by providing more surface area exposed to the water. In combination, the three "tiers" of the surface texture — the cavity separation, the posts, and the nanoscale texturing — provide a greatly enhanced efficiency for the boiling process, Song says... The nanostructures promote evaporation under the bubbles, and the capillary action induced by the pillars supplies liquid to the bubble base. That maintains a layer of liquid water between the boiling surface and the bubbles of vapor, which enhances the maximum heat flux.
While the article stresses it's still a laboratory-scale process (needing more work to become a practical "industry-scale" process), "There may be some significant small-scale applications that could use this process in its present form, such as the thermal management of electronic devices, an area that is becoming more important as semiconductor devices get smaller and managing their heat output becomes ever more important." Wang says in the announcement, "There's definitely a space there where this is really important." The article includes a bizarre-looking video showing how water now boils on their specially treated surface.

Thanks to Slashdot reader joshuark for sharing the link!

Haider Warraich, a cardiologist, writing for the New York Times: An intriguing new study from Germany offers a glimpse into how SARS-CoV-2 affects the heart. Researchers studied 100 individuals, with a median age of just 49, who had recovered from Covid-19. Most were asymptomatic or had mild symptoms. An average of two months after they received the diagnosis, the researchers performed M.R.I. scans of their hearts and made some alarming discoveries: Nearly 80 percent had persistent abnormalities and 60 percent had evidence of myocarditis. The degree of myocarditis was not explained by the severity of the initial illness.

Though the study has some flaws, and the generalizability and significance of its findings not fully known, it makes clear that in young patients who had seemingly overcome SARS-CoV-2 it's fairly common for the heart to be affected. We may be seeing only the beginning of the damage. Researchers are still figuring out how SARS-CoV-2 causes myocarditis -- whether it's through the virus directly injuring the heart or whether it's from the virulent immune reaction that it stimulates. It's possible that part of the success of immunosuppressant medications such as the steroid dexamethasone in treating sick Covid-19 patients comes from their preventing inflammatory damage to the heart. Such steroids are commonly used to treat cases of myocarditis. Despite treatment, more severe forms of Covid-19-associated myocarditis can lead to permanent damage of the heart -- which, in turn, can lead to heart failure.

"Light-to-moderate" alcohol consumption can help reduce your risk of Alzheimer's disease.

An anonymous reader quotes the Washington Post: A study presented Sunday at the Alzheimer's Association International Conference in Los Angeles found that combining five lifestyle habits -- including eating healthier, exercising regularly and refraining from smoking -- can reduce the risk of Alzheimer's by 60 percent. A separate study showed that lifestyle choices can lower risk even for those who are genetically prelifestyle disposed to the disease...

Over the last decade, studies have increasingly pointed to controllable lifestyle factors as critical compenents to reducing the risk of cognitive decline. Researchers say that, as with heart disease, combating dementia will probably require a "cocktail" approach combining drugs and lifestyle changes. And as recent efforts to develop a cure or more effective drug treatments for dementia have proven disappointing, the fact that people can exert some control in preventing the disease through their own choices is encouraging news, they say.

While the new study's authors expected to see that leading a healther life decreases the chance of dementia, they were floored by the "magnitude of the effect," said Klodian Dhana, a Rush University professor and co-author. "This demonstrates the potential of lifestyle behaviors to reduce risk as we age," said Heather Snyder, senior director of medical and scientific operations at the Alzheimer's Association. "The fact that four or five lifestyle habits put together can have that kind of benefit for your brain is incredibly powerful."
The fifth lifestyle habit is "engaging in mentally stimulating activities like reading the newspaper, visiting the library or playing games such as chess and checkers."

Time reports that even following just two or three of the healthy lifestyle factors reduced the risk of developing Alzheimer's dementia in the study by at least 39%.

"Deep, non-REM sleep helps people's brains to wash away toxic proteins and waste, a new study found, reinforcing the link between sleep deprivation, aging and Alzheimer's disease," reports U.S. News & World Report.

Or, as Discover magazine puts it, "Getting enough deep sleep might be the key to preventing dementia." The discovery reinforces how critical quality sleep is for brain health and suggests sleep therapies might curb the advance of memory-robbing ailments, like Alzheimer's disease... Cerebrospinal fluid (CSF) churns through a system of brain tunnels piped in the spaces between brain cells and blood vessels. Scientists call it the glymphatic system. This system circulates nutrients like glucose, the brain's primary energy source, and washes away potentially toxic waste. And it may be the reason why animals even need sleep. The system takes out the brain's trash when we're asleep, and it shuts down when we're awake.

Maiken Nedergaard, a neurologist at the University of Rochester Medical Center in New York, who led the new research, and her team were curious if the system works best and clears more waste -- like Alzheimer's causing beta amyloid plaque -- when animals are in deep sleep. To find out, the researchers used six different anesthetics to put mice into deep sleep. Then they tracked cerebrospinal fluid as it flowed into the brain. As the mice slept, the researchers watched the rodents' brain activity on an electroencephalograph, or EEG, and recorded the animals' blood pressures and heart and respiratory rates. Mice anesthetized with a combination of two drugs, ketamine and xylazine, showed the strongest deep sleep brain waves and these brain waves predicted CSF flow into the brain, the researchers found.
The lead researcher now argues that focusing on sleep in the early stages of dementia "might be able to slow progression of the disease."

An anonymous reader quotes a report from The Guardian: Children are increasingly finding it hard to hold pens and pencils because of an excessive use of technology, senior pediatric doctors have warned. An overuse of touchscreen phones and tablets is preventing children's finger muscles from developing sufficiently to enable them to hold a pencil correctly, they say. "Children are not coming into school with the hand strength and dexterity they had 10 years ago," said Sally Payne, the head pediatric occupational therapist at the Heart of England foundation NHS Trust. "Children coming into school are being given a pencil but are increasingly not be able to hold it because they don't have the fundamental movement skills. "To be able to grip a pencil and move it, you need strong control of the fine muscles in your fingers,. Children need lots of opportunity to develop those skills." Payne said the nature of play had changed. "It's easier to give a child an iPad than encouraging them to do muscle-building play such as building blocks, cutting and sticking, or pulling toys and ropes. Because of this, they're not developing the underlying foundation skills they need to grip and hold a pencil."

Artem Tashkinov shares a report from Medical Xpress: Antidepressant medications, most commonly prescribed to reduce depression and anxiety, increase the risk of death, according to new findings by a McMaster-led team of researchers. It's widely known that brain serotonin affects mood, and that most commonly used antidepressant treatment for depression blocks the absorption of serotonin by neurons. It is less widely known, though, that all the major organs of the body -- the heart, kidneys, lungs, liver -- use serotonin from the bloodstream. Antidepressants block the absorption of serotonin in these organs as well, and the researchers warn that antidepressants could increase the risk of death by preventing multiple organs from functioning properly.

Interestingly, the news about antidepressants is not all bad. The researchers found that antidepressants are not harmful for people with cardiovascular diseases such as heart disease and diabetes. This makes sense since these antidepressants have blood-thinning effects that are useful in treating such disorders. Unfortunately, this also means that for most people who are in otherwise good cardiovascular health, antidepressants tend to be harmful. The study has been published in the journal Psychotherapy and Psychosomatics.

An anonymous reader writes: "A bug in the iOS WebView component allows an attacker to force someone's iPhone to dial any number, while also locking the user's interface for a few moments, preventing him to cancel the outgoing call," reports BleepingComputer. "The bug was at the heart of the recent accidental DDoS of 911 call centers across the U.S." At the heart of the issue is a Safari bug reported in 2008, which was fixed in iOS 3.0. The same bug also exists in the WebView component used by app makers to show web pages inside other apps. The researcher that found the bug writes in a blog post: "If you think automatically dialing a phone number after clicking a link in an app is not a big issue think again. DoSing 911 is pretty terrible but there are other examples such as expensive 900 numbers where the attacker can actually make money. A stalker can make his victim dial his phone number so he gets his victim's number. Altogether things you don't want to happen. [...] Apple should change the default behavior of WebViews to exclude execution of TEL URIs and make it an explicit feature to avoid this kind of issues in the future."

An anonymous reader writes: A research team led by scientists at the UNC School of Medicine and the National Institutes of Health has unearthed more evidence that casts doubt on the traditional "heart healthy" practice of replacing butter and other saturated fats with corn oil and other vegetable oils high in linoleic acid. The findings, reported today in the British Medical Journal, suggest that using vegetable oils high in linoleic acid might be worse than using butter when it comes to preventing heart disease, though more research needs to be done on that front. This latest evidence comes from an analysis of previously unpublished data of a large controlled trial conducted in Minnesota nearly 50 years ago, as well as a broader analysis of published data from all similar trials of this dietary intervention. The analyses show that interventions using linoleic acid-rich oils failed to reduce heart disease and overall mortality even though the intervention reduced cholesterol levels. In the Minnesota study, participants who had greater reduction in serum cholesterol had higher rather than lower risk of death. Two things to note about the study: 75% of the participants left in less than a year (perhaps not uncommon, the study doesn't explain why these people left); the vegetable oils mentioned in the article are not necessarily the most commonly used (which are oils made of olive, sunflower, coconut, and palm).

Recently you had a chance to ask John McAfee about his presidential run under the newly-formed Cyber Party. John covers a wide variety of topics from education and infrastructure, to gun control and drug legalization. Read below for his answers to your questions.

HonorPoncaCityDotCom writes "For all the wonders of fresh broccoli, in most parts of the country it is only available from local growers during the cooler weeks at either end of the growing season, nowhere near long enough to become a fixture in grocery stores or kitchens. But now Michael Moss writes in the NY Times that Thomas Bjorkman is out to change all that by creating a new version of the plant that can thrive in hot, steamy summers like those in New York, South Carolina or Iowa and is easy and inexpensive enough to grow in large volumes. And Bjorkman's quest doesn't stop there: His crucifer is also crisp, subtly sweet and utterly tender when eaten fresh-picked and aims to maximize the concentration of glucoraphanin, a mildly toxic compound used by plants to fight insects that in humans may stimulate our bodies' natural chemical defenses to aid in preventing cancer and warding off heart disease. The Eastern Broccoli Project's goal is to create a regional food network for an increasingly important and nutritious vegetable that may serve as a model network for other specialty crops to help shift American attitudes toward fruits and vegetables by increasing their allure and usefulness in cooking, while increasing their nutritional loads. 'If you've had really fresh broccoli, you know it's an entirely different thing,' says Bjorkman, a plant scientist at Cornell University. 'And if the health-policy goal is to vastly increase the consumption of broccoli, then we need a ready supply, at an attractive price.'"

Hugh Pickens writes in about the detrimental effects of mandatory helmet laws (at least as applied to adults): "Elisabeth Rosenthal writes that in the United States the notion that bike helmets promote health and safety by preventing head injuries is taken as pretty near God's truth but many European health experts have taken a very different view. 'Yes, there are studies that show that if you fall off a bicycle at a certain speed and hit your head, a helmet can reduce your risk of serious head injury,' writes Rosenthal. 'But such falls off bikes are rare — exceedingly so in mature urban cycling systems.' On the other hand, many researchers say, if you force people to wear helmets, you discourage them from riding bicycles causing more health problems like obesity, heart disease, and diabetes. Bicycling advocates say that the problem with pushing helmets isn't practicality but that helmets make a basically safe activity seem really dangerous, which makes it harder to develop a safe bicycling network like the one in New York City, where a bike-sharing program is to open next year. The safest biking cities are places like Amsterdam and Copenhagen, where middle-aged commuters are mainstay riders and the fraction of adults in helmets is minuscule. 'Pushing helmets really kills cycling and bike-sharing in particular because it promotes a sense of danger that just isn't justified — in fact, cycling has many health benefits,' says Piet de Jong. 'Statistically, if we wear helmets for cycling, maybe we should wear helmets when we climb ladders or get into a bath, because there are lots more injuries during those activities.'"

New submitter daleallan writes "Triclosan, which is widely used in consumer handsoaps, toothpaste, clothes, carpets and trash bags, impairs muscle function in animal studies, say researchers at UC Davis (abstract). It slows swimming in fish and reduces muscle strength in mice. It may even impair the ability of heart muscle cells to contract. The chemical is in everyone's home and pervasive in the environment, the lead researcher says. One million pounds of Triclosan is produced in the U.S. annually and it's found in waterways, fish, dolphins, human urine, blood and breast milk. The researchers say their findings 'Call for a dramatic reduction in use.' It's in my Colgate Total toothpaste, and in fact, preventing gingivitis is the only use that may be worthwhile, although this makes me think twice about continuing to brush with it." This isn't the first time Triclosan has been in the news over safety concerns.

THE_WELL_HUNG_OYSTER writes "The curative effects of coffee continue to be discovered as the Harvard School of Public Health and Boston's Brigham & Women's Hospital published a new study today that links caffeine consumption with reduced skin cancer rates. Quoting: 'The study of nearly 113,000 men and women found those who drank three or more cups of coffee a day had a 20 percent lower risk of basal cell carcinoma than those who said no to Joe. Caffeine in non-coffee substances was found equally effective. The cause is speculated to be related to caffeine's ability to "kill off damaged skin cells," said Dr. Josh Zeichner, assistant professor of dermatology at Mount Sinai Medical Center in New York. "If you get rid of these cells that are damaged, then they don't have the opportunity to grow and form cancers."'"

kkleiner writes "For years, research has shown that aspirin is beneficial in preventing heart attacks. Now new studies support its ability to prevent cancer as well. The studies, involving tens of thousands of participants over many decades, show reductions of cancer incidence (both short- and long-term) and mortality rate as well as a decrease in metastatic cancer. It still is not known exactly how aspirin and cancer are connected, but those between the ages of 45-50 will now likely consider taking low-dose aspirin daily for the remainder of their lives."

Slashdot readers both contributed and helped moderate questions for the New Voters Project Presidential Youth Debate. You can read the answers below, but if you'd like to see an expanded introduction, thumbnails of the candidates, and different formatting, go to the Youth Debate page. And that's not all: We're supposed to get candidates' rebuttals on or about October 17, so don't touch that dial!

Paul Kocher, president of Cryptography Research, Inc. and one of the architects of SSL 3.0, said, "The questions were great -- definitely one of the most fun interviews I've ever done." His answers score high on the 'informative' scale, too. Thanks to everyone who submitted such fine questions, and thanks to Paul for putting some real time and effort into his answers.

cpfeifer writes with the review below of O'Reilly's 802.11 Wireless Networks: The Definitive Guide; he warns that this is not a book for everyone setting up a casual home wireless network, but says it's excellent for its intended audience. Read on for his complete review.

Two more presidential aspirants have sent answers to Slashdot questions: Republican Party candidate George W. Bush and Natural Law Party candidate John Hagelin. Not surprisingly, there are many issues on which they don't agree.

Thursday, I flew to Charlotte to ask executives of the Pinkerton Special Services Group to scrap or modify WAVE America, a "school safety" Web site that encourages schoolkids to anonymously turn in classmates they consider dangerous. We brawled politely for hours over chicken salad, iced tea and fries about school safety, oddball profiling, privacy and reality. Although righteously armed with some amazing and eloquent e-mailed screeds, reports, quotes, studies and pleas from Slashdotters, my expectations were low. I returned with a penetrating glimpse into the corporatist soul. (Read more).

kerouac points out a Boston Globe story about a man charged with civil rights violations for his Web site, after a slow two-year investigation. He writes: "Okay... I don't want to start a race flame-war, but it looks like the courts are starting to regulate 'hate speech'. I take pride in the fact that my bleeding-heart liberalism makes me hate what this guy's site is all about, but the U.S. courts are regulating/censoring this person's right to be a jerk." As described, the Web page sounds like a death threat, which would not be protected speech. A Wired story has more detail. For some reason the DoJ has not filed criminal charges for the alleged threat, so the man is being charged under the Fair Housing Act for preventing someone from making use of the FHA.