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Wen Su
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Red sprites

Far above a thunderstorm in the English Channel, red sprites are dancing in the upper atmosphere.

You can't usually see them from the ground - they happen 50 to 90 kilometers up. People usually photograph them from satellites or high-flying planes. But this particular bunch was videotaped from a distant mountain range in France by Stephane Vetter, on May 28th.

Sprites are quite different from lightning. They're not electric discharges moving through hot plasma. They involve cold plasma - more like a fluorescent light.

They're quite mysterious. People with high speed cameras have found that a sprite consists of balls of cold plasma, 10 to 100 meters across, shooting downward at speeds up to 10% the speed of light... followed a few milliseconds later by a separate set of upward moving balls!

Sprites usually happen shortly after a lightning bolt. And about 1 millisecond before a sprite, people often see a sprite halo: a faint pancake-shaped burst of light approximately 50 kilometres across 10 kilometres thick.

Don't mix up sprites and ELVES - those are something else, for another day:

https://en.wikipedia.org/wiki/Sprite_(lightning)

https://en.wikipedia.org/wiki/Upper-atmospheric_lightning#ELVES

You also shouldn't confuse sprites with terrestrial gamma-ray flashes. Those are also associated to thunderstorms, but they actually involve antimatter:

https://en.wikipedia.org/wiki/Terrestrial_gamma-ray_flash

A lot of weird stuff is happening up there!

The photo is from here:

https://apod.nasa.gov/apod/ap170615.html

#physics
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So many QTIIPS around...

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Heartbreaking...
A MUST READ. PERIOD

I had a family, a career, a house in the suburbs—the American dream. And then I had a slave.

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Cycles.
The saltier your diet, the higher your energy expenditure

Excerpt:
«The body relies on this essential mineral for a variety of functions, including blood pressure and the transmission of nerve impulses. Sodium levels in the blood must be carefully maintained.
[…]
New studies of Russian cosmonauts, held in isolation to simulate space travel, show that eating more salt made them less thirsty but somehow hungrier. Subsequent experiments found that mice burned more calories when they got more salt, eating 25 percent more just to maintain their weight.

The research, published recently in two dense papers in The Journal of Clinical Investigation, contradicts much of the conventional wisdom about how the body handles salt and suggests that high levels may play a role in weight loss.
[…]
Dr. Titze noticed something puzzling in the crew members’ data: Their urine volumes went up and down in a seven-day cycle. That contradicted all he’d been taught in medical school: There should be no such temporal cycle.

In 1994, the Russian space program decided to do a 135-day simulation of life on the Mir space station. Dr. Titze arranged to go to Russia to study urine patterns among the crew members and how these were affected by salt in the diet.

A striking finding emerged: a 28-day rhythm in the amount of sodium the cosmonauts’ bodies retained that was not linked to the amount of urine they produced. And the sodium rhythms were much more pronounced than the urine patterns.

The sodium levels should have been rising and falling with the volume of urine.
[…]
The real shocker came when Dr. Titze measured the amount of sodium excreted in the crew’s urine, the volume of their urine, and the amount of sodium in their blood.

The mysterious patterns in urine volume persisted, but everything seemed to proceed according to the textbooks. When the crew ate more salt, they excreted more salt; the amount of sodium in their blood remained constant, and their urine volume increased.

“But then we had a look at fluid intake, and were more than surprised,” he said.

Instead of drinking more, the crew were drinking less in the long run when getting more salt. So where was the excreted water coming from?

“There was only one way to explain this phenomenon,” Dr. Titze said. “The body most likely had generated or produced water when salt intake was high.”

Another puzzle: The crew complained that they were always hungry on the high-salt diet. Dr. Titze assured them that they were getting exactly enough food to maintain their weights, and were eating the same amount on the lower-salt diets, when hunger did not seem to be problem.

But urine tests suggested another explanation. The crew members were increasing production of glucocorticoid hormones, which influence both metabolism and immune function.

To get further insight, Dr. Titze began a study of mice in the laboratory. Sure enough, the more salt he added to the animals’ diet, the less water they drank. And he saw why.

The animals were getting water — but not by drinking it. The increased levels of glucocorticoid hormones broke down fat and muscle in their own bodies. This freed up water for the body to use.

But that process requires energy, Dr. Titze also found, which is why the mice ate 25 percent more food on a high-salt diet. The hormones also may be a cause of the strange long-term fluctuations in urine volume.

Scientists knew that a starving body will burn its own fat and muscle for sustenance. But the realization that something similar happens on a salty diet has come as a revelation.

People do what camels do, noted Dr. Mark Zeidel, a nephrologist at Harvard Medical School who wrote an editorial accompanying Dr. Titze’s studies. A camel traveling through the desert that has no water to drink gets water instead by breaking down the fat in its hump.

One of the many implications of this finding is that salt may be involved in weight loss. Generally, scientists have assumed that a high-salt diet encourages a greater intake of fluids, which increases weight.

But if balancing a higher salt intake requires the body to break down tissue, it may also increase energy expenditure.»

— Gina Kolata. "Why Everything We Know About Salt May Be Wrong." The New York Times (May 8, 2017)
https://www.nytimes.com/2017/05/08/health/salt-health-effects.html

References:

• Kitada K et al. "High salt intake reprioritizes osmolyte and energy metabolism for body fluid conservation." J Clin Invest (2017 May 1) vol. 127 (5) pp. 1944-1959 DOI: 10.1172/JCI88532
https://www.jci.org/articles/view/88532
https://www.ncbi.nlm.nih.gov/pubmed/28414295

• Rakova N et al. "Increased salt consumption induces body water conservation and decreases fluid intake." J Clin Invest (2017 May 1) vol. 127 (5) pp. 1932-1943 DOI: 10.1172/JCI88530
https://www.jci.org/articles/view/88530
https://www.ncbi.nlm.nih.gov/pubmed/28414302

Comment:
When you fast for several days, you also lose a lot of water, and apparently also sodium.
I lost almost a kilogram of weight daily over an 8-day period.
I didn't feel thirsty so I didn't drink much, but the volume of urine was also notably smaller than usual. I don't think I was producing nearly 1 L of urine, so I guess I lost much of that water in my breath and through perspiration.
I have to add that by Western standards I am on a very low-sodium diet (when I'm eating), much lower than those "cosmonauts".

URL G+ post source comment:
plus.google.com/+EstherWojcicki/posts/ioe67Tjontq

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"So let’s start with empathy. Politically, empathy is akin to solidarity, born of the understanding that we are all in this together. In what together? For starters, we are in the uncertainty together."

https://charleseisenstein.net/essays/hategriefandanewstory/

"We are entering a space between stories. After various retrograde versions of a new story rise and fall and we enter a period of true unknowing, an authentic next story will emerge. What would it take for it to embody love, compassion, and interbeing?...All of them source from empathy, the result of the compassionate inquiry: What is it like to be you?"

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Finding higher purpose is hard. Is there such a thing for everyone?

Not sure if I agree with everything in this article, but one thing that caught my eye:
"What most people don’t understand is that passion is the result of action, not the cause of it."

If you want to find your higher purpose, let everything you do become part of the searching. One's higher purpose may not be something glamorous or inspiring, it may just be the thing that makes him/her content.

http://www.upworthy.com/how-i-found-my-lifes-passion-by-asking-myself-these-ridiculous-questions

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Some of the greatest romances of my life have been friendships. And these friendships have been, in many ways, more mysterious than erotic love: more subtle, less selfish, more attuned to kindness.
This, I have come to understand, is a love story.

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