For centuries, civilizations have harnessed energy from water. However, hydropower often requires large bodies of water to move heavy machinery, confining its use to rivers. But what if the electricity needed to light up your house could be generated from raindrops hitting its roof? 

To achieve this, scientists rely on electrical charges created when materials come into contact and then separate, a phenomenon called the triboelectric effect. As an example, rubbing a balloon against your hair gives them opposite charges, causing your hair to stand up and stick to the balloon. Scientists apply the same principle to make droplet-based triboelectric nanogenerators, or D-TENGS, where raindrops slide across negatively charged surfaces. As the droplets move, their positive charges gather near the surface, freeing up their negative charges. When the droplets reach a metal strip called an electrode, these negative charges flow into a circuit, generating electricity. However, water often remains on D-TENG electrode surfaces, blocking subsequent droplets and corroding the device.

Researchers at the China Three Gorges University and the Chinese Academy of Sciences approached this problem by modifying the shape of the electrodes used in D-TENGs. They proposed that a needle rather than a strip would help droplets detach quickly, allowing charge to flow into a device that uses inexpensive components. They called this design a needle electrode droplet-based triboelectric nanogenerator, or NED-TENG.

To build the NED-TENG, the researchers prepared a plastic film using a water-repellent polymer called polytetrafluoroethylene as the negatively charged surface. They inserted a copper wire through the center of the plastic film, protruding 3 millimeters (0.1 inches) from the front side to form the needle-shaped electrode exposed to raindrops. Meanwhile, they attached copper foil to the plastic film’s backside as a second electrode, completing the circuit. The team connected both electrodes to an instrument that measures electrical performance and mounted the components on an acrylic sheet, sealing it with waterproof tape.

To simulate raindrops, the team inclined the NED-TENG at 50° from a table and dispensed tap water drop by drop from 30 centimeters (12 inches) above its plastic film. Like conventional D-TENGs, the device generated electricity as droplets slid across the film and contacted the needle electrode. However, because the water touched only a small area of the needle, it easily slid off the NED-TENG, preventing the water from building up like in D-TENGs.

The researchers then evaluated and optimized the device using 2 metrics: the force driving charges through its circuit, or voltage, and how fast its charges transfer, or current. First, they compared the NED-TENG with a conventional D-TENG. The NED-TENG generated about 564 Volts (V) and 5 milliamperes (mA) of current, nearly twice the voltage and 3 times the current of the D-TENG, and enough to power small electronics like indicator lights.

Next, they varied the droplets’ release height to maximize electricity production. They found that increasing the release height from 10 to 30 centimeters (4 to 12 inches) increased both voltage and current, peaking at about 543 V and 4 mA. At greater heights, droplets splashed hard on impact, scattering the water and disrupting the charging process they observed in sliding droplets. 

Similarly, the researchers tested different device inclination angles, ranging from 10° to 70°. Their tests revealed that the device’s electrical performance increased at steeper angles and peaked at 50°, reaching 521 V and 3 mA. At steeper angles, droplets spent less time in contact with the surface, reducing electrical output. They explained that because triboelectric materials are highly sensitive, results can vary slightly between experiments, leading to individual peak values that are lower than the highest overall outputs. 

The researchers then explored how the technology might perform in a simulated rooftop installation. To reduce power fluctuations during real-world applications, they connected multiple NED-TENGs. They observed that 10 connected devices could fill a small energy-storage component within 2 minutes and power 200 LED lights.

Overall, the NED-TENGs shed water efficiently and generated more electricity than D-TENGs, while remaining simple to build. The team noted that future upscaled studies should examine how rooftop systems can direct rainwater onto the devices at optimal heights, and how droplets interact with their surfaces to improve long-term performance. With further development, these low-cost systems could turn rooftops into practical generators powered by everyday rainfall. 

The post Needles turn rain into electricity appeared first on Sciworthy.

Our sweets cravings may have set the stage for the human brain to become big and powerful. That’s the finding of a new study.

The brains of our upright-walking ancestors, some 4 million years ago, weighed only around 300 grams (11 ounces). That’s about equal to a medium apple. Today, the human brain averages 1,500 grams (3.3 pounds). That’s about equal to 1.5 liters of water. Much of this brain expansion took place before early humans mastered both fire and cooking. That’s a point that marked when they could start regularly dining on energy-dense starches.

Carbohydrates come in two main classes. Sugars tend to be relatively simple molecules. Starches tend to be bigger and more complex. A new analysis of existing data from human ancestors, as well as chimps, suggests that a large share of their energy probably came from sugary carbs, such as those in fruits and honey.

Simple sugars may have played an overlooked — but important — role in human evolution, researchers now conclude. They describe why in the August 6 Science.

Until now, much of how diet affected human evolution has centered on meat. Around 2.5 million years ago, our early upright-walking ancestors began eating more meat — raw at first, then eventually cooked. Meat is rich in protein and fat. And that appeared to play a big role in fueling our ancestors’ ever-expanding brains.

But Jennie Brand-Miller thought there might be more to the story. A nutrition scientist at the University of Sydney, in Australia, she wondered how sugars might have affected the evolution of our brains.

A 2017 study had shown that fruit-eating primates had bigger brains than leaf-eating ones. Eating fruit boosts demands on various thought processes, other researchers had suggested two decades earlier. Might this have kickstarted the evolution of big brains in humans?

Explains Brand-Miller, “You need to remember when various species of ripe fruit begin to ripen, then you need to remember where it is in the forest.” And, she adds, “Your memory is associated with a bigger brain.”

Fossil primates and later hominids, such as Homo erectus, showed signs of tooth decay, Brand-Miller notes. This suggests a diet containing soft, sugary foods. (Homo erectus was the first of our ancient cousins to venture outside Africa; that was 2 million years ago).

“All these things kept adding pieces to this lovely tapestry, this puzzle that said fruit-containing sugars must be important [in human evolution],” she says.

Still, what about meat?

Brand-Miller is part of a team that has now calculated the dietary needs of chimps, humans and three early species of human ancestors. To do this, the researchers combined data from fossils, teeth, the species’ metabolism and the biology of bodily processes.

Our earliest chimp-like ancestors from around 4 million years ago were largely vegetarians, they found. Fruit likely provided more than two-thirds of their food energy. And it played a big role as hominid brains grew over the next few million years, the data also suggest.

Clever foraging skills would have helped fuel their energy-sapping brains. These would have included hunting, cracking nuts, grinding seeds or extracting bone marrow. Later, once cooking became common, humans could have turned to starches (such as grains, beans and tubers). But a constant need for sugary foods appears to have been a key player in our evolution. And it didn’t disappear after a shift to foods high in proteins and fat, such as meats.

Meat and sugars? “I see them as parallel stories, not one replacing the other,” Brand-Miller now says. “Animal foods were clearly important. They’re very nutrient dense.”

A past focus on meat-eating may have missed some food trends that helped build the human brain, agrees Julie Lee-Thorp. She’s an archaeologist at the University of Oxford in England. She did not take part in the new study.

Focusing on meat’s role may reflect a modern bias, she adds. “Meat is a high-status food today,” notes Lee-Thorp. “And that has perhaps been carried over into the way we think about the past.”

But Brian Wood largely dismisses that. The study of human evolution has not been obsessed with meat-eating, he says. A biological anthropologist, Wood works at the University of California, Los Angeles. A diverse range of foods fueled our evolution, he says. And they were made possible by our growing “ability to capture and harvest high-quality, difficult-to-acquire foods.” This included hunting, sure. But, he adds, foraging for fruit, honey, nuts and the underground parts of plants was also part of it.

The transplanted cells formed circuits, reached the spinal cord and responded to injury.

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Although the famous Carrington Event of 1859 is often described as the first major space weather event to affect technology, earlier incidents did occur. Historical records show that telegraph systems were disrupted by geomagnetic storms as early as the late 1840s.

The post Study: Famous ‘Space Weather’ Train Delay Actually Happened Seven Years Later appeared first on Sci.News: Breaking Science News.

The animals may help reveal the causes of brain disease in people and point the way to treatments. But researchers already are calling for new ethical guidelines.

Experts say that after childbirth, intrusive thoughts are common and mostly benign. Lindsay Clancy’s story provides a disturbing exception.

Scientists have uncovered two surprising forces that help guide how the human brain forms before birth. Before birth, the human brain is shaped in large part by an unusual class of stem cells known as radial glia. These cells help determine which brain cells are produced, when they appear, and how the cerebral cortex, the [...]

Models of the insect’s nervous system have been trained to solve a Rubik’s Cube, play video games and even parallel park a car.

Models of the insect’s nervous system have been trained to solve a Rubik’s Cube, play video games and even parallel park a car.

The evolutionary part of this paper relies on wishful thinking. What “could” or “might” happen occurs only in their evolutionary imaginations.

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Alzheimer’s may begin to unravel the brain when a small group of neurons switches on a receptor it was never meant to use, triggering damage that spreads from synapses to memories. Alzheimer’s disease is often defined by amyloid plaques and tau tangles, but those hallmarks are part of a much wider breakdown. Neurons become overactive, [...]

Children with ADHD showed more erratic pupil responses, a pattern that shifted with medication.

Scientists simulated what happens when the pipes and tunnels that divert rainwater fail. In one scenario, 30 percent of local residents couldn’t reach an E.R.

The device made by Flow Neuroscience is approved by the FDA and could help people get off antidepressants—but it costs $2,200.

As far as completely pointless ways to kill time on your phone, this is certainly one of the weirdest on record.

Behold the all-new invention of so-called “dopamine sites” — digital domains where you can browse and hunt for deals on nonexistent wares and services. Clothes, food delivery, you name it: you can pretend-shop for it all. 

You don’t actually buy anything, crucially. You’re just pretending to have money to buy the things you want. It’s window-shopping reimagined for the age of doomscrolling.

But it’s also a little more than that. These cleverly-built sites simulate the experience down to checking out and “tracking” your shipment or delivery, and their absurdly realistic rituals can help people become more conscious of their spending habits. Supposedly. 

The trend, according to the New York Times, originated in South Korea this spring, when Park Seohyun, a 21-year-old mechanical engineering student in Seoul, created a fake food-delivery site called “Food Never Arrives.” (It’s now an app).

Originally intended as a joke, she says, it lets you not only order nonexistent food, but provides you an estimate of the money and calories you saved by skipping on the real thing. 

In a wintry economic climate, it became an unexpected hit.

“People began sharing it online and discussing whether it actually helped them resist ordering food,” Park told the NYT.

A wave of imitators followed. This summer marked the launch of “FakeHaul,” a dopamine site built by a Microsoft engineer that convincingly imitates shopping on Temu. Two developers in India inspired by Park’s site, Purvansh Parmar and Anshul Sharma, created “Food Never Comes,” which simulates food deliveries but provides real recipes for the food you didn’t actually order. Parmar and Sharma told the newspaper that their site had more than 2.7 million views since launching in June.

Whether these dopamine sites provide anything more than fleeting, empty pleasures is something experts are more skeptical about. Ravi Dhar, director of the Yale Center for Customer Insights, told the NYT that the “element of looking forward brings a lot of the pleasure, and we often crash after an event or feel let down.” Lingguo Xu, a behavioral economist studying anticipatory utility, warned that the dopamine tricks could quickly get old. And by simulating consumption, you risk developing “stronger cravings.”

Some take the original idea beyond getting high on simulated shopping. Ko Seojin, another South Korean developer, created a website for taking virtual smoke breaks called Damta World. You click to start smoking an animated cigarette, which starts burning on screen. You can “whisper” disappearing messages to other smokers on break, while a counter keeps track of the number of cigarette butts that have been tossed on the office rooftop each day.

Ko told the NYT that 150,000 people visit each month, and she says that some users have become real-life friends after meeting on the website. Those friendships, we hope, are something that’ll last longer than any fake-shopping dopamine hit.

More on your brain on tech: Psychologist Says AI Is Causing Never-Before-Seen Types of Mental Disorder

The post Bizarre New Websites Are Designed Specifically to Spark Dopamine in Your Brain appeared first on Futurism.

The US government has been sharing more information about UFOs. That's fueling excitement over the possibility of the president announcing that humans are not alone.

The US government has been sharing more information about UFOs. That's fueling excitement over the possibility of the president announcing that humans are not alone.

It’s easy to see why people might latch onto the idea of a reptilian brain as an explainer, or an explainaway, for complex topics.

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For the 25th anniversary of 9/11 you may be wondering what to read or watch for the occasion. I have a few suggestions.

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After nearly two decades of work, scientists have completed a wiring diagram of the central nervous system of an adult male fruit fly (Drosophila melanogaster).

The post Researchers Unveil Complete Fruit Fly Connectome appeared first on Sci.News: Breaking Science News.