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Daily briefing: Top tips for undergraduates looking to break into the lab

Daily briefing: Top tips for undergraduates looking to break into the lab

Daily briefing: Top tips for undergraduates looking to break into the lab, Published online: 18 March 2019; doi:10.1038/d41586-019-00940-1

How to find research work and make the most of it, stem-cell therapy for corneas and controversial deep-sea mining is about to be put to the test http://feeds.nature.com/nature/rss/current via https://www.nature.com/articles/d41586-019-00940-1

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Attosecond angular streaking and tunnelling time in atomic hydrogen

Attosecond angular streaking and tunnelling time in atomic hydrogen

Attosecond angular streaking and tunnelling time in atomic hydrogen, Published online: 18 March 2019; doi:10.1038/s41586-019-1028-3

Simulation and measurement of the photoionization of atomic hydrogen at attosecond resolution confirm that the tunnelling of the ejected electron is instantaneous. http://feeds.nature.com/nature/rss/current via https://www.nature.com/articles/s41586-019-1028-3

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Visualizing DNA folding and RNA in embryos at single-cell resolution

Visualizing DNA folding and RNA in embryos at single-cell resolution

Visualizing DNA folding and RNA in embryos at single-cell resolution, Published online: 18 March 2019; doi:10.1038/s41586-019-1035-4

Optical reconstruction of chromatin architecture and multiplex RNA labelling traces the DNA path in single cells and its relationship to transcription. http://feeds.nature.com/nature/rss/current via https://www.nature.com/articles/s41586-019-1035-4

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Art and the Nocturnal Imagination: Painter, Poet, and Philosopher Etel Adnan on Dreaming and Creativity

“The logic of dreams is superior to the one we exercise while awake. In dreams the mind at last finds its courage: it dares what we do not dare.”


Art and the Nocturnal Imagination: Painter, Poet, and Philosopher Etel Adnan on Dreaming and Creativity

Nietzsche saw dreams as an evolutionary time machine for the human mind. Dostoyevsky discovered the meaning of life in one. Mendeleev invented his periodic table in another. Neil Gaiman dreamt his way to a philosophical parable of identity. We are born dreaming. As we go through life, dream-sleep plays plays a major role in regulating our negative emotions.

When we dream, we are our most essential and sovereign selves — our shadows the starkest, our creativity the wildest, and all of it, crucially, ours alone. We build and unravel entire worlds, answering to no one but ourselves — and even that, only hazily. Graham Greene celebrated this sovereignty when he observed in his dream diary that “it can be a comfort sometimes to know that there is a world which is purely one’s own — the experience in that world, of travel, danger, happiness, is shared with no one else.”

Illustration by Tom Seidmann-Freud from a philosophical 1922 children’s book about dreaming

We still don’t know exactly why the human animal needs to sleep, much less to dream. But we do know that the mechanism churning our nocturnal fancies is closely related to the faculty we call creativity. Dreams may be the most populist art there is and the wellspring of our most visionary masterpieces.

That is what the Lebanese-American poet, painter, and philosopher Etel Adnan (b. February 24, 1925) explores in a few meditative passages from Journey to Mount Tamalpais (public library) — the 1986 treasure that gave us Adnan on time, self, impermanence, and transcendence.

Adnan writes:

I always thought that dreaming was the honor of the human species. The logic of dreams is superior to the one we exercise while awake. In dreams the mind at last finds its courage: it dares what we do not dare. It also creates: from nightmares to fantastic calculations… and it perceives reality beyond our fuzzy interpretations. In dreams we swim and fly and we are not surprised.

[…]

Dreams spill over on our days. For some people they never stop spilling: the visionaries, the hobos, and all those who speak to themselves, aloud, in the big cities.

Illustration by Judith Clay from Thea’s Tree

Adnan considers the parallels between dreaming and creative work:

Sometimes, while painting, something wild gets unleashed. Something of the process of dreams recurs… but with a special kind of violence: a painting is like a territory. All kinds of things happen within its boundary, equal to the discoveries of the murders or the creations we have in the world outside.

We translate our dreams on paper and cloth, subduing them, most of the time, fearing that moment of truth which has energy enough to blow up the world.

Couple with Adnan on the self and the universe, then revisit Mark Strand’s stunning poem about dreams and Billy Hayes on the science of sleep and sleeplessness.


donating = loving

Bringing you (ad-free) Brain Pickings takes me hundreds of hours each month. If you find any joy and stimulation here, please consider becoming a Supporting Member with a recurring monthly donation of your choosing, between a cup of tea and a good dinner.


newsletter

Brain Pickings has a free weekly newsletter. It comes out on Sundays and offers the week’s most unmissable reads. Here’s what to expect. Like? Sign up.

from Brain Pickings https://www.brainpickings.org/2019/03/18/etel-adnan-journey-to-mount-tamalpais-dreaming/

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Art and the Nocturnal Imagination: Painter, Poet, and Philosopher Etel Adnan on Dreaming and Creativity

“The logic of dreams is superior to the one we exercise while awake. In dreams the mind at last finds its courage: it dares what we do not dare.”


Art and the Nocturnal Imagination: Painter, Poet, and Philosopher Etel Adnan on Dreaming and Creativity

Nietzsche saw dreams as an evolutionary time machine for the human mind. Dostoyevsky discovered the meaning of life in one. Mendeleev invented his periodic table in another. Neil Gaiman dreamt his way to a philosophical parable of identity. We are born dreaming. As we go through life, dream-sleep plays plays a major role in regulating our negative emotions.

When we dream, we are our most essential and sovereign selves — our shadows the starkest, our creativity the wildest, and all of it, crucially, ours alone. We build and unravel entire worlds, answering to no one but ourselves — and even that, only hazily. Graham Greene celebrated this sovereignty when he observed in his dream diary that “it can be a comfort sometimes to know that there is a world which is purely one’s own — the experience in that world, of travel, danger, happiness, is shared with no one else.”

Illustration by Tom Seidmann-Freud from a philosophical 1922 children’s book about dreaming

We still don’t know exactly why the human animal needs to sleep, much less to dream. But we do know that the mechanism churning our nocturnal fancies is closely related to the faculty we call creativity. Dreams may be the most populist art there is and the wellspring of our most visionary masterpieces.

That is what the Lebanese-American poet, painter, and philosopher Etel Adnan (b. February 24, 1925) explores in a few meditative passages from Journey to Mount Tamalpais (public library) — the 1986 treasure that gave us Adnan on time, self, impermanence, and transcendence.

Adnan writes:

I always thought that dreaming was the honor of the human species. The logic of dreams is superior to the one we exercise while awake. In dreams the mind at last finds its courage: it dares what we do not dare. It also creates: from nightmares to fantastic calculations… and it perceives reality beyond our fuzzy interpretations. In dreams we swim and fly and we are not surprised.

[…]

Dreams spill over on our days. For some people they never stop spilling: the visionaries, the hobos, and all those who speak to themselves, aloud, in the big cities.

Illustration by Judith Clay from Thea’s Tree

Adnan considers the parallels between dreaming and creative work:

Sometimes, while painting, something wild gets unleashed. Something of the process of dreams recurs… but with a special kind of violence: a painting is like a territory. All kinds of things happen within its boundary, equal to the discoveries of the murders or the creations we have in the world outside.

We translate our dreams on paper and cloth, subduing them, most of the time, fearing that moment of truth which has energy enough to blow up the world.

Couple with Adnan on the self and the universe, then revisit Mark Strand’s stunning poem about dreams and Billy Hayes on the science of sleep and sleeplessness.


donating = loving

Bringing you (ad-free) Brain Pickings takes me hundreds of hours each month. If you find any joy and stimulation here, please consider becoming a Supporting Member with a recurring monthly donation of your choosing, between a cup of tea and a good dinner.


newsletter

Brain Pickings has a free weekly newsletter. It comes out on Sundays and offers the week’s most unmissable reads. Here’s what to expect. Like? Sign up.

from Brain Pickings https://www.brainpickings.org/2019/03/18/etel-adnan-journey-to-mount-tamalpais-dreaming/

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CoreStretch

I have chronic back pain and osteoporosis and use a CoreStretch ($75) (in conjunction with a Spine-Worx) to reduce spinal compression and decrease pain. I’ve used it for about 8 years and it seems to be working beautifully; I have much less pain and haven’t needed to visit a chiropractor since using it.

I’m a pharmacist and researched other options thoroughly before choosing this. An inversion table may be a superior device for stretching the spine…but it’s also huge, ugly, unwieldy, and expensive. This costs less than a chiro visit, and I can easily tuck it behind my bedroom door. I’m also not fond of that “full head” feeling you get with an inversion table when the blood pressure increases in the brain. This is just bending over; your cranial blood pressure is largely unaffected.

It’s well built, and there really isn’t much that could go wrong with it. It still looks like new after years of use. It’s simple to use: sit down (I use the edge of my bed) and put the padded bar on your lap, tucked up next to your torso. Adjust the length of the handles so that your arms are comfortably stretched when you grasp them. Grab hold and gently lean forward; your whole spine will get a nice stretch. I usually stretch gently from one side to another, making a shallow “U” that’s only about a foot wide, trying to go just slightly deeper with each pass.

There is a whole range of suggested positions you can use to stretch different areas and muscle groups. I only use it for a minute or two, then move onto the Spine-Worx for a few minutes. This regimen works well, as evidenced by much less pain, and the fact that my spine has stopped shrinking (a potential problem with osteoporosis). When I use it, I generally have a pain-free day. Your mileage may vary, of course…but if you’re looking for a spinal stretcher that won’t break the bank, this is worth a try. If you’ve wondered whether an inversion table might help you, but haven’t got the room or money for one, you might give this a try!

— Barbara Dace

CoreStretch ($75)

Available from Amazon

via https://kk.org/cooltools/corestretch/

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The rise and fall of scientific authority — and how to bring it back

The rise and fall of scientific authority — and how to bring it back

The rise and fall of scientific authority — and how to bring it back, Published online: 18 March 2019; doi:10.1038/d41586-019-00872-w

Robert P. Crease harks back to the shapers of our scientific infrastructure and what they can tell us about how to handle the threat we now face. http://feeds.nature.com/nature/rss/current via https://www.nature.com/articles/d41586-019-00872-w

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Podcast Episode 241: A Case of Scientific Self-Deception

https://commons.wikimedia.org/wiki/File:Prosper_Ren%C3%A9_Blondlot.jpg

//html5-player.libsyn.com/embed/episode/id/9034367/height/90/theme/custom/thumbnail/no/direction/backward/render-playlist/no/custom-color/000000/

In 1903, French physicist Prosper-René Blondlot decided he had discovered a new form of radiation. But the mysterious rays had some exceedingly odd properties, and scientists in other countries had trouble seeing them at all. In this week’s episode of the Futility Closet podcast we’ll tell the story of N-rays, a cautionary tale of self-deception.

We’ll also recount another appalling marathon and puzzle over a worthless package.

Intro:

In the 1960s, two dolphins at Hawaii’s Sea Life Park were inadvertently switched and performed each other’s acts.

Franz Bibfeldt is an invisible scholar at the University of Chicago divinity school.

Sources for our feature on Prosper-René Blondlot and the N-rays:

René Blondlot, Julien François, and William Garcin, “N” Rays: A Collection of Papers Communicated to the Academy of Sciences, With Additional Notes and Instructions for the Construction of Phosphorescent Screens, 1905.

William Seabrook, Doctor Wood, 1941.

Walter Gratzer, The Undergrowth of Science: Delusion, Self-Deception, and Human Frailty, 2001.

Terence Hines, Pseudoscience and the Paranormal, 2003.

Richard C. Brown, Are Science and Mathematics Socially Constructed?, 2009.

Robert W. Proctor and E.J. Capaldi, Psychology of Science: Implicit and Explicit Processes, 2012.

Paul Collins, Banvard’s Folly, 2015.

Roelf Bolt, The Encyclopaedia of Liars and Deceivers, 2014.

Walter Gratzer and Walter Bruno Gratzer, Eurekas and Euphorias: The Oxford Book of Scientific Anecdotes, 2004.

Robert W. Wood, How to Tell the Birds From the Flowers, 1907.

Robert W. Wood, “The n-Rays,” Nature 70:1822 (1904), 530-531.

Mary Jo Nye, “N-Rays: An Episode in the History and Psychology of Science,” Historical Studies in the Physical Sciences 11:1 (1980), 125-156.

Robert T. Lagemann, “New Light on Old rays: N Rays,” American Journal of Physics 45:281 (1977), 281-284.

Irving M. Klotz, “The N-ray Affair,” Scientific American 242:5 (1980), 168-175.

John Butler Burke, “The Blondlot n-Rays,” Nature 70 (June 30, 1904), 198.

John Butler Burke, “The Blondlot n-Rays,” Nature 69 (Feb. 18, 1904), 365.

Jeffrey Kovac, “Reverence and Ethics in Science,” Science and Engineering Ethics 19:3 (September 2013), 745-56.

Nancy S. Hall, “The Key Role of Replication in Science,” Chronicle of Higher Education 47:11 (Nov. 10, 2000), B14.

“The Blondlot Rays,” British Medical Journal 1:2245 (Jan. 9, 1904), 90.

“The Romance of the Blondlot Rays,” British Medical Journal 1:2244 (Jan. 2, 1904), 35-36.

“Blondlot and Prof. Wood on the N-Rays,” Scientific American 91:25 (Dec. 17, 1904), 426.

Malcolm Ashmore, “The Theatre of the Blind: Starring a Promethean Prankster, a Phoney Phenomenon, a Prism, a Pocket, and a Piece of Wood,” Social Studies of Science 23:1 (1993), 67-106.

Luis Campos, “The Birth of Living Radium,” Representations 97:1 (Winter 2007), 1-27.

“The Latest Wonder of Science,” Public Opinion 4:36 (Jan. 28, 1904), 115-116.

J.J. Stewart, “The N-Rays of Blondlot,” Knowledge & Scientific News 2:10 (September 1905), 218-219.

“Science and Invention: Radio-Activity,” Current Literature 38:3 (March 1905), 258.

J.R. Whitehead, “Radioactivity and Radiation,” Electrical World and Engineer 43:7, 310.

Mark Pilkington, “N-Rays Exposed,” Guardian, Sept. 1, 2004.

“Latest Scientific Discovery,” Leavenworth [Wash.] Echo, April 8, 1910, 4.

Listener mail:

Karen Abbott, “The 1904 Olympic Marathon May Have Been the Strangest Ever,” Smithsonian.com, Aug. 7, 2012.

Wikipedia, “1904 Summer Olympics” (accessed March 7, 2019).

Wikipedia, “Athletics at the 1904 Summer Olympics – Men’s Marathon” (accessed March 7, 2019).

Brian Cronin, “Sports Legend Revealed: A Marathon Runner Nearly Died Because of Drugs He Took to Help Him Win,” Los Angeles Times, Aug. 10, 2010.

Wikipedia, “George Eyser” (accessed March 9, 2019).

Wikipedia, “Andarín Carvajal” (accessed March 9, 2019).

“1956 Olympic Long Jump Champion Krzesinska Dies,” IAAF News, Dec. 30, 2015.

This week’s lateral thinking puzzle was contributed by listener Murli Ravi. Here are two corroborating links (warning — these spoil the puzzle).

You can listen using the player above, download this episode directly, or subscribe on Google Podcasts, on Apple Podcasts, or via the RSS feed at https://futilitycloset.libsyn.com/rss.

Please consider becoming a patron of Futility Closet — you can choose the amount you want to pledge, and we’ve set up some rewards to help thank you for your support. You can also make a one-time donation on the Support Us page of the Futility Closet website.

Many thanks to Doug Ross for the music in this episode.

If you have any questions or comments you can reach us at podcast@futilitycloset.com. Thanks for listening!

from Futility Closet https://www.futilitycloset.com/2019/03/18/podcast-episode-241-a-case-of-scientific-self-deception/

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Podcast Episode 241: A Case of Scientific Self-Deception

https://commons.wikimedia.org/wiki/File:Prosper_Ren%C3%A9_Blondlot.jpg

//html5-player.libsyn.com/embed/episode/id/9034367/height/90/theme/custom/thumbnail/no/direction/backward/render-playlist/no/custom-color/000000/

In 1903, French physicist Prosper-René Blondlot decided he had discovered a new form of radiation. But the mysterious rays had some exceedingly odd properties, and scientists in other countries had trouble seeing them at all. In this week’s episode of the Futility Closet podcast we’ll tell the story of N-rays, a cautionary tale of self-deception.

We’ll also recount another appalling marathon and puzzle over a worthless package.

Intro:

In the 1960s, two dolphins at Hawaii’s Sea Life Park were inadvertently switched and performed each other’s acts.

Franz Bibfeldt is an invisible scholar at the University of Chicago divinity school.

Sources for our feature on Prosper-René Blondlot and the N-rays:

René Blondlot, Julien François, and William Garcin, “N” Rays: A Collection of Papers Communicated to the Academy of Sciences, With Additional Notes and Instructions for the Construction of Phosphorescent Screens, 1905.

William Seabrook, Doctor Wood, 1941.

Walter Gratzer, The Undergrowth of Science: Delusion, Self-Deception, and Human Frailty, 2001.

Terence Hines, Pseudoscience and the Paranormal, 2003.

Richard C. Brown, Are Science and Mathematics Socially Constructed?, 2009.

Robert W. Proctor and E.J. Capaldi, Psychology of Science: Implicit and Explicit Processes, 2012.

Paul Collins, Banvard’s Folly, 2015.

Roelf Bolt, The Encyclopaedia of Liars and Deceivers, 2014.

Walter Gratzer and Walter Bruno Gratzer, Eurekas and Euphorias: The Oxford Book of Scientific Anecdotes, 2004.

Robert W. Wood, How to Tell the Birds From the Flowers, 1907.

Robert W. Wood, “The n-Rays,” Nature 70:1822 (1904), 530-531.

Mary Jo Nye, “N-Rays: An Episode in the History and Psychology of Science,” Historical Studies in the Physical Sciences 11:1 (1980), 125-156.

Robert T. Lagemann, “New Light on Old rays: N Rays,” American Journal of Physics 45:281 (1977), 281-284.

Irving M. Klotz, “The N-ray Affair,” Scientific American 242:5 (1980), 168-175.

John Butler Burke, “The Blondlot n-Rays,” Nature 70 (June 30, 1904), 198.

John Butler Burke, “The Blondlot n-Rays,” Nature 69 (Feb. 18, 1904), 365.

Jeffrey Kovac, “Reverence and Ethics in Science,” Science and Engineering Ethics 19:3 (September 2013), 745-56.

Nancy S. Hall, “The Key Role of Replication in Science,” Chronicle of Higher Education 47:11 (Nov. 10, 2000), B14.

“The Blondlot Rays,” British Medical Journal 1:2245 (Jan. 9, 1904), 90.

“The Romance of the Blondlot Rays,” British Medical Journal 1:2244 (Jan. 2, 1904), 35-36.

“Blondlot and Prof. Wood on the N-Rays,” Scientific American 91:25 (Dec. 17, 1904), 426.

Malcolm Ashmore, “The Theatre of the Blind: Starring a Promethean Prankster, a Phoney Phenomenon, a Prism, a Pocket, and a Piece of Wood,” Social Studies of Science 23:1 (1993), 67-106.

Luis Campos, “The Birth of Living Radium,” Representations 97:1 (Winter 2007), 1-27.

“The Latest Wonder of Science,” Public Opinion 4:36 (Jan. 28, 1904), 115-116.

J.J. Stewart, “The N-Rays of Blondlot,” Knowledge & Scientific News 2:10 (September 1905), 218-219.

“Science and Invention: Radio-Activity,” Current Literature 38:3 (March 1905), 258.

J.R. Whitehead, “Radioactivity and Radiation,” Electrical World and Engineer 43:7, 310.

Mark Pilkington, “N-Rays Exposed,” Guardian, Sept. 1, 2004.

“Latest Scientific Discovery,” Leavenworth [Wash.] Echo, April 8, 1910, 4.

Listener mail:

Karen Abbott, “The 1904 Olympic Marathon May Have Been the Strangest Ever,” Smithsonian.com, Aug. 7, 2012.

Wikipedia, “1904 Summer Olympics” (accessed March 7, 2019).

Wikipedia, “Athletics at the 1904 Summer Olympics – Men’s Marathon” (accessed March 7, 2019).

Brian Cronin, “Sports Legend Revealed: A Marathon Runner Nearly Died Because of Drugs He Took to Help Him Win,” Los Angeles Times, Aug. 10, 2010.

Wikipedia, “George Eyser” (accessed March 9, 2019).

Wikipedia, “Andarín Carvajal” (accessed March 9, 2019).

“1956 Olympic Long Jump Champion Krzesinska Dies,” IAAF News, Dec. 30, 2015.

This week’s lateral thinking puzzle was contributed by listener Murli Ravi. Here are two corroborating links (warning — these spoil the puzzle).

You can listen using the player above, download this episode directly, or subscribe on Google Podcasts, on Apple Podcasts, or via the RSS feed at https://futilitycloset.libsyn.com/rss.

Please consider becoming a patron of Futility Closet — you can choose the amount you want to pledge, and we’ve set up some rewards to help thank you for your support. You can also make a one-time donation on the Support Us page of the Futility Closet website.

Many thanks to Doug Ross for the music in this episode.

If you have any questions or comments you can reach us at podcast@futilitycloset.com. Thanks for listening!

from Futility Closet https://www.futilitycloset.com/2019/03/18/podcast-episode-241-a-case-of-scientific-self-deception/

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The Cognitive Reflection Test

Answer these questions:

  1. A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost? _____ cents
  2. If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets? _____ minutes
  3. In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half of the lake? _____ days

The correct answers are 5 cents, 5 minutes, and 47 days, but each question also invites a quick, intuitive response that’s wrong. In order to succeed, you have to suppress your “gut” response and reflect on your cognition deeply enough to see the error. Psychologist Shane Frederick devised the test in 2005 to illustrate these two modes of thought, unreflective and reflective, which he called System 1 and System 2.

Scores on the CRT correlate with various measures of intelligence, patience, and deliberation, but cognitive ability alone isn’t strongly correlated with CRT scores: If you’re not prone to answering impulsively then the problems aren’t hard, and if you do answer impulsively then cognitive ability won’t help you. A sample of students at MIT averaged 2.18 correct answers, Princeton 1.63, Carnegie Mellon 1.51, Harvard 1.43; see the link below for more.

(Shane Frederick, “Cognitive Reflection and Decision Making,” Journal of Economic Perspectives 19:4 [2005], 25-42.) (Thanks, Drake.)

from Futility Closet https://www.futilitycloset.com/2019/03/17/the-cognitive-reflection-test/

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Bad Blood/Free Solo/Sunday Soother

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Bad Blood
My wife and I tore through John Carreyrou’s Bad Blood. It’s the story of Theranos, the fraudulent Silicon Valley startup that promised to revolutionize health but instead perpetrated a potentially murderous scam. The founder surrounded herself with ultrarich powerful people who were blind to obvious warning signs because they were so enamored with the idea that they were going to make billions of dollars. This real-life tale beats any fictional corporate thriller. — MF

Maniacal performance
The fantastic documentary Free Solo deserves all praise it has received, including its recent Oscar. The film follows one guy’s attempt to climb the vertical face of Yosemite’s El Capitan without ropes. A single slip he dies. I could barely watch it, it was that crazy good. As the climber’s friend put it: this demands an Olympic gold medal performance, except here, if you don’t get the gold, you die. The film has suspense, drama, emotion, and explores maniacal obsession and perfection. Five stars. Now streamable. — KK

Sunday Soother
I love reading The Sunday Soother by Catherine Andrews — a newsletter about practical spirituality. Each week she shares her thoughts and processes for slowing down and creating more meaning in life, as well as articles, books, beauty products, recipes and more. It’s like getting an intimate letter from a friend. Each email is a tool for self-reflection. Her last two issues were dedicated to grief and ambiguous loss — which I learned is a particular type of loss that lacks a definition and closure. She solicited stories from her readers and here is what was shared.

Narwhal for Reddit
If you have an iPhone, Narwhal is the best app to access Reddit. It’s snappy, and highly customizable and much easier to use than Reddit’s own app. — MF

Happiness practices around the world
I’ve stumbled upon these ten little drawings of happiness practices all over the internet, and they still make me happy. I like learning untranslatable words that stretch the imagination. My favorite from this set is the idea of forest bathing. — CD

Smallest, cheapest flashlight
This ThorFire is the brightest, cheapest ($15), smallest, lightest LED flashlight that runs on a single AA (rechargeable) battery. Rugged, made of metal, it will stand up on its end. I have them everywhere. — KK

— Kevin Kelly, Mark Frauenfelder, Claudia Dawson

via https://kk.org/cooltools/33224/

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Slitherlink

https://commons.wikimedia.org/wiki/File:SurizaL%C3%B6sung.png
Image: Wikimedia Commons

In this original logic puzzle by the Japanese publisher Nikoli, the goal is to connect lattice points to draw a closed loop so that each number in the grid denotes the number of sides on which the finished loop bounds its cell, as above: Each cell bearing a “1” is bounded on 1 side, a “2” on 2 sides, and so on.

Here’s a moderately difficult puzzle. Can you solve it? (A loop that merely touches a cell’s corner point without passing along any side is not considered to bound it.)

https://commons.wikimedia.org/wiki/File:Slitherlink-example.png
Image: Wikimedia Commons

from Futility Closet https://www.futilitycloset.com/2019/03/16/slitherlink/