A pulsar orbited by a white dwarf star, which are both orbited by another white dwarf, provide confirmation of the principle of universality of free fall



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RELATED: NASA’s Curiosity Rover Detects Methane and Organic Material on Mars

Dust storms are a fairly frequent event on Mars, but scientists struggle to forecast their severity. Sometimes these storms are more localized, and sometimes they blanket the entire planet — as the Mariner 9 mission witnessed when it arrived in 1971. Back then, only the peaks of some volcanoes were visible above the dust.

NASA said it will need better forecasts of dust storms before sending human crews to Mars, which the agency may do after returning to the moon in the 2020s.

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Thu, 14 Jun 2018 16:28:29 -0500
Physical states appear to shape emotions and cognition. Here’s why — along with a few steps on how to avoid becoming hangry.no-reply@thrillist.com Jennifer MacCormack, The ConversationJennifer MacCormack, The Conversationhttp://www.seeker.com/culture/heres-how-a-hungry-person-becomes-a-hangry-person?utm_medium=RSS&utm_source=feeds Credit: Image Source via Getty Images
Have you ever been grumpy, only to realize that you’re hungry?

Many people feel more irritable, annoyed, or negative when hungry — an experience colloquially called being “hangry.” The idea that hunger affects our feelings and behaviors is widespread — from advertisements to memes and merchandise. But surprisingly little research investigates how feeling hungry transforms into feeling hangry.

Psychologists have traditionally thought of hunger and emotions as separate, with hunger and other physical states as basic drives with different physiological and neural underpinnings from emotions. But growing scientific evidence suggests that your physical states can shape your emotions and cognition in surprising ways.

Prior studies show that hunger itself can influence mood, likely because it activates many of the same bodily systems, like the autonomic nervous system and hormones, that are involved in emotion. For example, when you’re hungry, your body releases a host of hormones including cortisol and adrenaline, often associated with stress. The result is that hunger, especially at greater intensity, can make you feel more tense, unpleasant, and primed for action — due to how these hormones make you feel.

But is feeling hangry just these hunger-induced feelings or is there more to it? This question inspired the studies that psychologist Kristen Lindquist and I conducted at UNC-Chapel Hill. We wanted to know whether hunger-induced feelings can transform how people experience their emotions and the world around them.

Negative situations set the scene for hanger
An idea in psychology known as affect-as-information theory holds that your mood can temporarily shape how you see the world. In this way, when you’re hungry, you may view things in a more negative light than when you’re not hungry. But here’s the twist.

People are most likely to be guided by their feelings when they’re not paying attention to them. This suggests that people may become hangry when they aren’t actively focused on their internal feelings, but instead wrapped up in the world around them, such as that terrible driver or that customer’s rude comment.

To test whether hungry people are more likely to become hangry in negative situations when they aren’t focused on their feelings, we designed three different studies. In the first two, run online with US adults, we asked people — some hungry, some full — to look at negative, positive, and neutral emotional images. Then they saw an ambiguous figure: a Chinese character or pictograph they’d never seen before. We asked participants whether they thought the pictograph meant something pleasant or unpleasant.


Credit: Jennifer MacCormack, CC BY-ND
Hungry people who saw negative images thought the pictographs meant something more unpleasant. However, hungry people’s ratings after positive or neutral emotional pictures were no different than the not-hungry people.

This suggests that the hangry bias doesn’t occur when people experience positive or even neutral situations. Instead, hunger only becomes relevant when people confront negative stimuli or situations. But why would hunger only matter in negative situations?

Affect-as-information theory also suggests that people are more likely to use their feelings as information about the world around them when those feelings match the situation they’re in. Hunger likely only becomes relevant in negative situations because hunger itself produces unpleasant feelings — making it easier to mistake the cause of those feelings to be the negative things around you, rather than your hunger.

Tuning in to your feelings
In the final study, we recreated in the laboratory a frustrating situation to test how hunger and awareness — or lack thereof — might cause hanger.

We assigned two random groups of undergraduate students to fast for at least five hours or eat a full meal before coming to our lab. There we assigned them to write a story that was meant either to direct their attention to emotional information, or to not focus on emotions at all. Then everyone did a long, tedious computer task. At the end of the task, we secretly programmed the computer to “crash.” The researcher blamed the participant for the computer malfunction and told them they’d have to redo the task once it was fixed.

It turned out that hungry people who hadn’t focused on feelings beforehand exhibited more signs of being hangry. They reported feeling more stressed, hateful, and other negative emotions and rated the researcher as being more “judgmental,” compared to full individuals and the hungry people who did write about emotions earlier.

These findings suggest that feeling hangry occurs when your hunger-induced negativity gets blamed on the external world around you. You think that person who cut you off on the road is the one who made you angry — not the fact that you’re ravenous. This seems to be a fairly unconscious process: People don’t even realize they’re making these attributions.

Our data suggest that paying attention to feelings may short circuit the hangry bias — and even help reduce hanger once you notice it.


Credit: Snickers
Although these studies provide a valuable glimpse into the ways that physical states, like hunger, can temporarily shape our feelings and behaviors, they are only a first step. For example, our studies only address hunger effects in healthy populations where individuals eat regularly. It would be interesting to look at how feeling hangry could change with long-term dieting or conditions like diabetes or eating disorders.

These studies alongside other emerging science suggest that our bodies can deeply shape how we think, feel and act — whether we realize it or not. We’re generally aware that emotions like feeling stressed can influence our health, but the reverse direction is also true. Our bodies and physical health have the power to shape our mental lives, coloring who we are and the way we experience the world around us.



Warding off hanger
Here are three pro tips to help keep your hunger from going full-blown hangry.

First, it may seem obvious, but pay more attention to your hunger. People vary a lot in how sensitive they are to hunger and other bodily cues. Maybe you don’t notice you’re hungry until you’re already ravenous. Plan ahead — carry healthy snacks, eat a protein-filled breakfast or lunch to give you lasting energy — and set yourself reminders to eat regularly. These basic precautions help prevent you from becoming overly hungry in the first place.

But what if you’re already super hungry and can’t eat right away? Our findings suggest people are more likely to be biased by hunger in negative situations. Maybe you’re stuck in bad traffic or you have a stressful deadline. In these cases, try to make your environment more pleasant. Listen to an amusing podcast while you drive. Put on pleasant music while you work. Do something to inject positivity into your experience.

Most importantly, your awareness can make all the difference. Yes, maybe you’re hungry and starting to feel road rage, overwhelmed with your task deadline, or wounded by your partner’s words. But amid the heat of those feelings, if you can, step back for a moment and notice your growling stomach. This could help you recognize that hunger is part of why you feel particularly upset. This awareness then gives you the power to still be you, even when you’re hungry.



Originally published at The Conversation. 

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Wed, 13 Jun 2018 15:47:14 -0500
Seeker's Bad Science podcast tackles the director’s eye-popping space epic.no-reply@thrillist.com Glenn McDonaldGlenn McDonaldhttp://www.seeker.com/space/black-holes-and-time-travel-the-science-behind-christopher-nolans-interstellar?utm_medium=RSS&utm_source=feeds
In 2014, director Christopher Nolan (The Dark Knight, Inception) released the hugely hyped space epic Interstellar. Set on (and off) a near-future Earth, the film imagines a scenario in which ecological degradation has turned the planet into a dying dustbowl that can no longer sustain human life.

In an effort to find a new home world for our species, what's left of NASA dispatches a team of astronauts to pilot their ship through a wormhole just past Saturn. After that, things get weird. Nolan's film is certainly ambitious. At nearly three hours running time, it takes viewers on an epic celestial scouting mission featuring interdimensional time warps and planet-spanning tsunamis. But how does the film hold up in regard to the actual science of space travel?



Interstellar gets a thorough cosmic dissection in the latest episode of Bad Science, Seeker's podcast dedicated to exploring the real scientific principles behind popular speculative fiction films. In this week's show, host Ethan Edenburg is joined by comedian Dan Levy and Varoujan Gorjian, research astronomer with NASA's Jet Propulsion Laboratory.

While it's generally acknowledged that the film's plot holes are bigger that its wormholes, Interstellar nevertheless takes its hard science seriously. The film covers a lot of territory, and the filmmakers famously collaborated with top researchers and astrophysicists on script details. All of which makes for one of the most delightfully nerdy Bad Science episodes so far.

“We've talked about Pacific Rim, we've talked about Harry and the Hendersons, these movies that are pretty simple as far as science is concerned,” says Edenburg.  â€œAnd then there's this, which feels like a behemoth that we could spend nine episodes on.”

Focusing on the core astrophysics behind the film's premise, guest scientist Gorjian provides a breakdown of the cosmic phenomenon known as the black hole.

“A black hole occurs when you have a lot of mass and a very little volume,” he says. “There are many ways to make a black hole, but the most common cause in our part of the universe is exploding stars.”

As Gorjian explains, the escape velocity required to pull away from a black hole is so titanic that it exceeds the speed of light.

“No light escapes it, it's black,” he says “If we could wave a wand and compress our sun to a sufficiently small size, it would become a black hole.”

RELATED: Robots Versus Monsters: The Real Science Behind Pacific Rim

Understanding the basics on black holes can help viewers appreciate the film's central premise of a wormhole, Gorjian says. In science fiction — and certain arcane branches of theoretical physics — wormholes are cosmic portals that fling matter and energy across vast distance of time and space.

“Wormholes, that was something that was conjectured by Einstein, originally,” Gorjian says. “He and another scientist named Rosen came up with the idea and it's technically called an Einstein-Rosen bridge.”

Tune in for this week's episode for more details on escape velocity, time dilation, and gravity wells. The knowledge may come in handy soon, too. In the last scenes of Interstellar, Nolan follows his blockbuster instincts and sets us up for a potential sequel. Might we suggest: Interstellar 2: Interstellarer. That thing will write itself!

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Tue, 12 Jun 2018 16:22:59 -0500
Feelings of disgust serve an evolutionary purpose, protecting us from potential health threats.no-reply@thrillist.com Jen ViegasJen Viegashttp://www.seeker.com/culture/disgust-helps-humans-avoid-infectious-diseases-but-the-emotion-isnt-perfect?utm_medium=RSS&utm_source=feeds Credit: fhm via Getty Images
Val Curtis arguably has one of the world's most stomach-churning jobs. As director of the  Environmental Health Group at the London School of Hygiene and Tropical Medicine, she investigates the emotion of disgust. Filthy bathrooms, urine-soaked city alleyways, and closeups of oozing lesions are all part of a typical day's work.

"I'm pretty inured to disgust," Curtis, who is the author of the book "Don't Look, Don't Touch, Don't Eat" (Chicago University Press, 2013), admitted to Seeker. "But like most people, I find excreta and bodily emanations pretty revolting."

Feelings of disgust turn out to facilitate infectious disease avoidance, according to new research conducted by Curtis and co-author Mícheál de Barra of Brunel University London. Their study, published in the Royal Society journal Philosophical Transactions B, strongly supports a theory holding that disgust functions to reduce contact with pathogens and parasites.

The scientists began their investigation by selecting a number of infectious diseases at random from a commonly referenced handbook concerning communicable disease epidemiology and control. Among those diseases, they extracted information about forms of transmission, such as via direct skin contact or airborne germs.

The researchers then generated a series of 75 scenarios that could, to varying degrees, mirror actual cues for those modes of disease transition. For example, exposure to bodily waste and other excretions was one of the identified infectious disease transmission routes. Their scenarios then included everything from seeing un-flushed excrement in a toilet to sitting next to someone on an airplane who is vomiting into a paper bag.

They also included some scenarios that might not seem so obviously off-putting. Since animals can be disease vectors, scenarios included imagining holding a "fat wriggling worm in your bare hands for 60 seconds," having a stray dog lick your face, and feeling a "hairless old cat" rubbing against your leg.

RELATED: Babies Appear to Understand Human Emotions at a Very Early Age

Still others concerned having "a woman with unkempt hair and disheveled clothes" sit beside you on a bus, "seeing an obese woman sunbathe" and "shaking hands with someone missing a thumb."

All of these scenarios were loaded into an online survey that was fully completed by 2,679 participants who were mostly from the US, UK, and Canada. For each survey entry, the participants were required to rate it on a spectrum with "no disgust" at one end and "extreme disgust" on the other.

The ratings showed that the scenarios most associated with sensorial cues for disease transmission routes were more often rated as being disgusting. The researchers further identified six basic types of disgust, based on the survey responses. They are disgust related to: hygiene, animals, sex, atypical appearances, lesions, and food.

Women were more likely than men to rate scenarios tied to all of these types as being disgusting. Women were also more often rated sex-related scenarios, such as seeing blisters or red dots on a partner's genitals, as being disgusting.

The survey respondents had to consciously consider each scenario, but if they were to have experienced these imagined instances in real life, their reactions would have occurred at both subconscious and conscious levels, Curtis suspects.

"All behavior is, to some extent, genetically programmed," she explained. "Our genetic makeup makes us enjoy the taste of sweetness and reject bitterness — somewhat modulated in later life by experience — for example. So, the sight or smell of feces produces a reaction that may happen before we are even conscious of it."

Disgust and fear can be interconnected, since both are adaptive systems that have evolved to enable avoidance of potential dangers.

"The point of these emotions is that they drive behavior, hence there is a physical and behavioral reaction," Curtis said. "There is also often a bodily reaction: The stomach churns in the expectation that it might need to eject something; the skin ‘crawls’ in expectation that one might need to scratch off a flea, for example."

Fleas themselves likely have their own evolved hygiene standards. Prior research has found that numerous animals behave in ways that may reduce their contact with harmful agents. Lobsters and mice, for example, avoid infected others. Nematodes and kangaroos steer clear of waste material. Birds and ants exhibit multiple hygienic behaviors.

Curtis, however, thinks it is unlikely that many non-human animals experience disgust as people do. She suspects that most of their disgust-related responses happen at a subconscious level.

A problem for humans is that our hardwiring for disease transmission cues may not always match real threats. Shaking hands with a person missing a thumb and viewing an obese individual sunbathing present no danger. Nevertheless, some people link such moments to feelings of disgust.

"In our evolutionary past, someone obese might be swollen up because of a disease, like filariasis," Curtis said. Filariasis is a parasitic disease caused by an infection with certain roundworms.

Nowadays, few people are overweight because of infectious illnesses, yet the past association may somehow be part of our genetic programming. "Disheveled" people, in turn, may be physically healthy, yet could elicit negative reactions for similar reasons.



RELATED: Storytelling Promoted Egalitarian Values Before the Advent of Religion

Humans may also view some perfectly fit animals as disgusting, simply because of similar long-held associations. A worm, for instance, "is a cue, looking a lot like a parasitic worm," Curtis said.

These mismatches between feelings of disgust and actual threats grow ever more complex when moral disgust is considered. The researchers did not tackle that loaded topic but theorize that moral disgust may have arisen as an extension of "hygiene disgust." Both forms can be affected by cultural factors.

The disgust system in humans is clearly imperfect, but it is at least useful to scientists in all of its respects.

"We need to understand how people respond to disease threats so that we can design programs to help people behave in ways that keep them safe from disease," Curtis said.

"So, for example, in another prior study where we wired up wash basins in public toilets in the UK, we found that people responded to messages such as ‘don’t take the toilet with you’ by washing their hands with soap more often," she continued. "In India the government very successfully uses disgust-based messaging to get people to build toilets."

She said that the disgust system also provides a great model for investigating other emotions with particular behavioral functions. Curtis shared that she and de Barra are now conducting these additional studies using similar methods in order to "pick these emotions apart."

A key to that ongoing effort, she said, is to consider what frequent related challenges early humans encountered.

"Evolution actually selects brains based on the behavior that helped our ancestors to survive and reproduce,” she said. Emotions are for behavior."

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Tue, 12 Jun 2018 15:23:29 -0500
Two new methods for harvesting water offer potential solutions for addressing the commodity’s scarcity — even in a desert.no-reply@thrillist.com Tracy StaedterTracy Staedterhttp://www.seeker.com/tech/these-technologies-can-harvest-water-from-thin-air?utm_medium=RSS&utm_source=feeds Credit: Tao Zhang/Getty Images
As the planet warms and global populations boom, water is becoming a scarce commodity.

Now, two separate projects demonstrate new technology to more efficiently harvest water from air than previous attempts. One shows a low-tech method for squeezing droplets from dry, desert air, while the other uses an electrostatic charge to drastically improve the amount of water collected from humid air. Both aim to create low-cost sources of freshwater that could slack the thirst of humans, crops, and even power plants.

The first water harvester comes from a team at UC Berkeley that has devised a simple box-in-a-box system that works using ambient air temperature without the need for refrigeration. In experiments, the system was able to produce between 2 and 3 1/2 ounces of water per day. That may sound small, but this is bone-dry desert air with a relative humidity that ranges from 40 percent at night to 8 percent in the daytime. The researchers report their findings in journal Science Advances.

A critical component of this system is a kind of powder that consists of metal-organic frameworks, also called MOFs. These tiny, synthetic crystalline grains can be made from a variety of metal ions bound to short organic molecules. MOFs, which were invented decades ago by the research team’s leader, Omar Yaghi, are incredibly porous and have surface structures so intricate that if a gram of them were laid out flat, they would cover several football fields.

For this water harvester, the researchers tested two different MOFs — those made from zirconium and others made from aluminum. For the inner box, a two-foot-tall plastic container, the researchers arranged an inch-deep layer of MOFs near the very top. They placed that box inside a larger, plastic box that has a transparent top and sides.  

At night, the lid to the outer box was left open to allow air to permeate the bed of MOFs and their porous structure. During the day, the lid to the outer box was closed, trapping heat inside, which released water vapor trapped inside the MOF. The vapor clung to the inside of the large box, condensed and dripped to the bottom, where it was collected.

“It doesn’t require much energy to get the water out,” graduate student Eugene Kapustin told Seeker.

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