Does anyone know where I can get 2 inch rollers with standard 7/16 bore, but without the shaft for garage doors. Everywhere I look they come with a shaft. My doors are old (antique) and the rollers are able to slide on the shaft rather than the shaft sliding in the hinge. I'm too cheap to buy new do
Interact With 12 Scientific Game Changers [Science]
Scientific American put together an interactive piece on 12 events that could drastically change the world, from nuclear exchange to cold fusion to the discovery of other dimensions. Pretty much all the stuff Lost totally prepared us for. More »
DC Power Supply
I'm trying to make a simple dc power supply w/ a full bridge rectifier, 2 caps, a pot, and a lm317. my transformer is a 120v to 25.2 v. I'm using this typical schematic and I know it works, but every time I turn the pot down to around 17v from a max of about 28v, the pot starts smoking, has any one
Discover Your Inner Godwit | The Loom
On March 29, 1912, Robert Scott and two fellow explorers huddled in a tent during a fierce Antarctic blizzard. They had landed on the edge of Antarctica five months earlier, hoping to be the first people in history to reach the South Pole. They succeeded in reaching the Pole, but it was a bitter success. They discovered that another team, led by Roald Amundsen, had gotten there first. So Scott and his team turned back and began the 800-mile journey back to the sea. They hauled sledges themselves, without the help of dogs. The plunging temperatures increased the friction of the snow, so that they had to put in as much effort as they would to haul the sledges through sand. On February 4, Edgar Evans dropped dead. On March 16, Laurence Oates, barely able to walk, simply left the camp and never came back. A blizzard on March 20 left them unable to leave their tent.
“I do not think we can hope for any better things now,” Scott wrote in his diary nine days later. “We shall stick it out to the end, but we are getting weaker, of course, and the end cannot be far.” And indeed he likely died that day. Scott and his crew were finally discovered eight months later.
Scott may not have been the first person to reach the South Pole, but he did earn a different kind of distinction: “the greatest human performances of sustained physical endurance of all time,” in the words of University of Cape Town sports scientist Timothy Noakes. All told, Scott probably burned about million calories. Each day he and his fellow explorers burned around 7,000 calories, about four times the rate of a man at rest.
Scott’s accomplishment was exceptional not just for a human, but for any animal. Animals rarely push their metabolism beyond about four times their resting rate for any length of time. A cheetah may explode into a sixty-mile-an-hour sprint, but for only a few seconds. Most animals that push themselves hard–birds racing around to find food for their chicks for days on end, for example–only push themselves about four times above their resting metabolic rate.
In 2007, however, a small bird left Scott in the dust. Scientists discovered that bar-tailed godwits could fly from Alaska to New Zealand, non-stop. Their metabolism, scientists found, rose to about eight times their resting rate. And it stayed there, 24 hours a day, for nine days. And while Scott could refuel on his journey by eating horse meat and pemmican, the bar-tailed godwits fasted for their entire 7,000 miles journey.
As I report in the lead story of the Science Times in tomorrow’s New York Times, research now shows that the bar-tailed godwit has some company. Using sophisticated new location-tracking devices, scientists have discovered other species several travel several thousand miles without a break.
I also write about the deeper significance of these new results. How do these birds achieve these awesome treks. And why? In a new paper, the Swedish biologist Anders Hederstrom argues that birds like bar-tailed godwits aren’t all that unusual. Lots of birds that go on much shorter migrations have many of the same adaptations as the champions–the ability to store up fat, an ability to navigate long distances, an efficient body shape, and so on.
Theunis Piersma, a Dutch biologist, offered up a provocative idea for the evolution of ultramarathoning birds. Their migrations may be able to shift quickly from short to long. Birds have a huge potential to work hard, without the need for long-term physical evolutionary changes coming first. All they need is a change in behavior, and their bodies will meet the challenge. Once they shift their behavior, natural selection may well favor physical changes that help them go long distances. (Piersma will write about this at length in his upcoming book, The Flexible Phenotype.)
For Piersma, what’s really interesting is why godwits and some other birds push so hard, while most other animals don’t. Piersma thinks that laziness is, for the most part, adaptive. If animals push themselves beyond about four times their resting metabolic rate, they usually have to pay dearly. They become vulnerable to predators and disease, for example. When scientists have added extra chicks to the nests of kestrel hawks, for example, the parents have to work harder to feed them. As a result, the scientists found, the parents became more likely to die. When scientists add little weights to bees that are buzzing around gathering nectar, the bees are also more likely to die. And Scott himself is a grisly illustration of Piersma’s tradeoff. His foot became infected so badly, he wrote, that “amputation is the best I can hope for.”
Flying over open seas, however, may allow some birds to escape this trade-off. Predators and parasites can’t catch them when they’re hundreds of miles from the nearest land. When bar-tailed godwits land after flying 7,000 miles, they can just take a long nap without worrying about being eaten. The very things that might make exhaustion more dangerous are missing from their migration.
For more, check out my story.
Update: And be sure to check out the great interactive maps.
[Images: Scott, Wikipedia/Godwits, Robert E. Gill]
NCBI ROFL: A long time ago in a galaxy far, far away, Jar Jar Binks had a fungal infection. | Discoblog
It's BMJ week (again) on NCBI ROFL! After the success of our first BMJ week, we decided to devote another week to fun articles from holiday issues of the British Medical Journal. Enjoy! Tokelau on Naboo "Tinea imbricata, a superficial fungal infection of man, has an ornate appearance composed of concentric circles and polycyclic or serpiginous scaly plaques. The condition is common in several humid tropical regions, especially in parts of Polynesia and Melanesia. It is also reported occasionally in the Amazon basin and other tropical areas in both hemispheres. The precise distribution of tinea imbricata, however, has been poorly defined ever since the disease was named by Sir Patrick Manson, the father of tropical medicine. I report the possible presence of tinea imbricata outside its previously known geographic and taxonomic distribution. Several Gungan inhabitants of Naboo, a planet of the Galactic Republic depicted in Star Wars Episode 1: The Phantom Menace, have skin with the distinctive annular and polycyclic pattern of tinea imbricata. Jar Jar Binks, a Gungan who figures prominently in this movie, shows this eruption in figure ?2. Manson wrote of the infection, “Again, tinea imbricata, if it has been in existence any length of time, involves a very large surface, as ...
Free Adobe Reader App Now Available for Android Devices [Android Apps]
The newest addition to the Android Marketplace is a free Adobe Reader app. It looks good, but keep in mind that it requires Android 2.1 or above and is currently only supported on some Android devices: More »
Does a Dose of Testosterone Make Trusting Women More Skeptical? | 80beats
All it takes for some people to be a little less trusting of their fellow humans is a little more testosterone, according to a new study in the Proceedings of the National Academy of Sciences.
Researchers led by Jack van Honk of the Netherlands used a sample of 24 women in their study. The team showed photos of 150 strangers’ faces to the women and asked them to rate the faces for trustworthiness, using a scale from -100 to +100. The scores women gave after receiving a placebo became their “baseline” score. The women also completed a trustworthiness survey after being given an increase in testosterone instead of placebo (they weren’t told when they received which).
Scientists found that women were not so easily taken in by a stranger’s face after receiving a dose of the hormone…. Women who appeared the most trusting after receiving the “dummy” placebo reduced their scores by an average of 10 points when their testosterone was boosted [Press Association].
Why? The researchers point to the social advantages testosterone can confer:
The study also adds support to the idea that testosterone influences human behavior, not necessarily by increasing aggression, but by motivating people to raise their status in the social hierarchy or become more socially dominant. Testosterone might boost social watchfulness, making those who are most trusting a little more vigilant and better prepared for competition over rank and resources, the researchers say [LiveScience].
This sample size isn’t terribly large and the explanation is something of a just-so story, but it’s at least a plausible one. The study authors say that testosterone’s effects specifically could balance out those of oxytocin, the “love hormone,” which previous studies have suggested could increase feelings of trust, or make men want to cuddle.
One curious detail of this study, though, is that the skepticism effect showed up only in the most trusting women. The ones who scored as the least trusting after the placebo test didn’t drop their scores lower and become extremely distrusting after a testosterone dose; they just stayed the same. Why should they stand pat instead of descending into testosterone-induced misanthropy?
Related Content:
80beats: Does Testosterone Cause Greedy Behavior? Or Do We Just Think It Does?
80beats: Men With High Testosterone Levels Make Riskier Financial Decisions
Discoblog: Turn a Man Into Mush with a Nasal Spray of Pure Oxytocin
Not Exactly Rocket Science: Can a Sniff of Oxytocin Improve the Social Skills of Autistic People?
Image: flickr / luc legay
Question of the Day: Is Mobile Flash Worth It to You? [Qotd]
So today we saw some tests that suggest that having Flash running on your smartphone will almost definitely hurt performance. But hey, it's up to you whether or not it's worth it. So...is it? More »
Why Google Is So Incredibly Rich [Google]
What SS Screw Can Achieve 500 Hour Salt Chamber Test
Hello, guys
Any of you are familiar with stainless steel screw who can pass 500 hours in salt chamber?
I NEED the UNS number designation like 321 (UNS S32100), 316L OR 347 (S34700)
kind regards
Mauricio
Cripes. Another rambling interview. | Bad Astronomy
I met Ken Plume last year at Dragon*Con. Our mutual Close Personal Friend Adam Savage™ introduced us, of all things. He runs a site called ASiteCalledFred and has lots of podcast interviews with interesting people, and he decided to break that streak and talk to me.
His chats are pretty free-form; he asks questions but lets things go where they may. He learned a lesson with me, no doubt. He let me ramble about The Monkees, my daughter’s first word, NASA, constellations, NASA, and I think NASA. We really did bop around from topic to topic, making it a Faulkneresque rapids ride of skepticism and science and some mild stabs at humor (on my part). I do talk at length about where I think NASA is, was, will be, and should be, so you might get a kick out of that. Give it a listen.
He does have a long list of interviews with some pretty cool people (Stephen Colbert! Tom Kenny! Julie Gardner! John Hodgman! Dave Foley! Olivia Wilde!), so check those out as well.
A Brief and Glorious History of Pixel Art [Documentaries]
Space Exploration Workshop Charts Online
NASA Announces Posting of Space Exploration Workshop Charts
"Presentation charts for the opening-day briefings of NASA's Exploration Enterprise Workshop in Galveston, Texas, will be posted online at noon EDT, Monday, May 24. The two-day workshop brings together a broad community of space exploration stakeholders from government, industry and academia. The Exploration Systems Mission Directorate's plans for human and robotic space exploration and the administration's fiscal year 2011 budget request for the agency will be discussed."
PLH Air Conditioning Unit (Mitsubushi)
Dose any body have an operating manual for a PLH-3GKLH-UK air conditioning unit. Drawing number BG7R519H01.
This unit is coming up with an error code of, EO. The unit is no longer listed by the manufacturer. The current problem came when it had water running out of it.
This unit must h
Classic Mac Paper Trashcan for Trash, Cans, Paper [Crafts]
After successfully following these instructions to make a paper classic Macintosh trashcan, please don't use the resulting paper classic Macintosh trashcan to trash any failed paper classic Macintosh trashcans. The paradox can destroy the Universe. Thank you. [Codeco via Designboom] More »
Photo: Heart and Soul Nebulae Reveal Star Birth in the Cold Dust | 80beats
What do you see in this image?
“One is a Valentine’s Day heart, and the other is a surgical heart that you have in your body,” said Ned Wright of the University of California, Los Angeles, who presented the image May 24 at a meeting of the American Astronomical Society. [Wired]
This infrared image is from WISE, more technically known as the Wide-field Infrared Survey Explorer, a NASA space telescope launched on December 14, 2009. Orbiting Earth at an altitude of 326 miles, WISE snaps an infrared picture every eleven seconds. This one, of the so-called Heart and Soul nebulae, is made from 1,147 of these images stitched together.
The Heart and Soul nebulae are over 6,000 light years away, in the constellation Cassiopeia. To capture beauties like these, WISE needs to stay cool enough that its own heat doesn’t distort the infrared images. For this reason, it carries a chunk of solid hydrogen, cryogen, that keeps the on-board telescope at about 17 degrees Kelvin (minus 429 degrees Fahrenheit). With its sensitive infrared vision, WISE can see the cool and dusty crevices of nebulae, where gas and dust are beginning to clump together to form new stars.
Having already taken about 960,000 images, the mission promises more pics like these for about four more months, until its cryogen supply runs out. Though this isn’t the first time we’ve seen these nebulae, WISE certainly has a unique perspective.
“WISE is the first survey capable of observing the two clouds in a uniform way, and this will provide valuable insight into the early solar system,” said astronomer Tommy Grav of Johns Hopkins University in Baltimore, Md., who presented the information at today’s meeting. [SPACE.com]
Related content:
80beats: A Hot Piece of Hardware: NASA’s New Orbiter Will Map the Entire Sky in Infrared
Bad Astronomy: A WISE flower blooms in space
Bad Astronomy: When a star struggles to be free of its chrysalis
Bad Astronomy: What does a nebula look like up close?
Image: NASA/JPL-Caltech/UCLA
Twitter, Twitter, Little Star (Chart) [Infographics]
Cosmic 140 is the star chart of the Twitter universe, its 140 most influential people. At its center, Evan Williams and Jack Dorsey. In the outer systems, much less important people, like Bill Gates, Tim Berners-Lee, and Conan O'Brien. More »
Solid State Drives – the Eventual Solution?
At last, new Silicon Disk Drives are on the market, with capacities to rival old-school Hard Disks, and speeds to greatly exceed those. They are cool, literally emit no heat, and virtually silent.
Oh yes... And they are virtually indestructible. Made of solid-state monoliths, they are shock
Should Dolphins and Whales Have “Human Rights”? | Discoblog
From the heroic Flipper to the charismatic Willy, dolphins and whales have made some splashy supporting actors. And since they often seem almost as smart and interesting as their human costars, perhaps it's not surprising that a new movement is afoot to grant these animals "human rights." Research on everything from whale communication to “trans-species psychology” hints that the glowing portrayals of these fictional animal friends have some basis in reality. If cetaceans—marine mammals including whales, dolphins, and porpoises—can act like humans, even using tools and recognizing themselves in a mirror, shouldn’t they have the same basic rights as people? That’s what attendees of a meeting organized by the Whale and Dolphin Conservation Society (WDCS) said yesterday, where a multidisciplinary panel agreed on a “Declaration of Rights for Cetaceans: Whales and Dolphins.” “We affirm that all cetaceans as persons have the right to life, liberty and well being,” says the Declaration, meant in part to stop current whaling practices. Thomas White, director of the Center for Ethics and Business at Loyola Marymount University in California, told Reuters:
"Whaling is ethically unacceptable.... They have a sense of self that we used to think that only human beings have."
This declaration conflicts with ongoing negotiations within the International Whaling ...
A Rifle’s Third Eye Helps Shoot Around Corners [Guns]
"Fifty percent of kills happen on the corners," according to SmartSight inventor Matthew Hagerty. And his creation—a rifle sight camera that wirelessly transmits real-time video back to its soldier—will help ensure that our soldiers win those battles. More »
