चीनी, नमक और पानी का घोल. किचन से वास्ता रखने वालों को ये नुस्खा तो शायद कई सौ साल पहले से ही पता होगा, लेकिन इस घोल में किस अनुपात में क्या हो, यह बताने में डॉक्टर नॉर्बर्ट हिर्सहॉर्न की अहम भूमिका रही. डॉक्टर नॉर्बर्ट के इस नुस्खे ने लगभग पाँच करोड़ ज़िंदगियाँ बचाई हैं.

मिस्र में एक तीन महीने का बच्चा दो दिन से डायरिया का शिकार है इस कदर कमज़ोर हो गया है कि वह दूध पीने के लिए मां के स्तन पर अपना सिर तक नहीं टिका पाता. अलेक्सांद्र के उपचार केंद्र में जब इस बच्चे को लाया गया तो एकबारगी डॉक्टर भी घबरा गए थे.

लेकिन उपचार के चार घंटे बाद ही वह मां का दूध पीने लगा और यह सब संभव हुआ चीनी, नमक और पानी के घोल से.
डॉक्टर नॉर्बर्ट का कहना है कि ओरल रिहाइड्रेशन थेरेपी के परिणाम अविश्वसनीय रहे हैं.

संतुलन की प्यास

डॉक्टर नॉर्बर्ट 1964 से ओरल रिहाइड्रेशन थेरेपी से जुड़े. वह अमरीका की सैन्य स्वास्थ्य सेवा में थे.
बांग्लादेश (तब पूर्वी पाकिस्तान) में हैजा गंभीर रूप ले चुका था. ऐसे वक़्त डॉक्टर नॉर्बर्ट को वहाँ भेजा गया. हैजा होने से मरीज के शरीर में पानी की भारी कमी हो जाती है और वह कुछ ही घंटों में दम तोड़ सकता है.

मिस्र में महिलाएं अपने बच्चों को नमक-चीनी का घोल पिलाते हुए

पूर्वी पाकिस्तान के लगभग 40 प्रतिशत गांवों में लोग हैज़े का इलाज न होने से मर रहे थे.
तब रिहाइड्रेशन का उपचार अस्पताल में नस के माध्यम से होता था. यह महंगा था और उनको नहीं मिल पाता था जिन्हें इसकी सबसे ज़्यादा ज़रूरत होती थी.

असाधारण नतीजे

इसलिए मुंह के रास्ते दिए जाने वाले उपचार पाने की कोशिशें की गई ताकि अधिक से अधिक लोगों की मदद की जा सके.
नमक, चीनी और पानी के सही अनुपात पर कई प्रयोग पहले भी हो चुके थे, लेकिन ये नाकामयाब रहे थे और कई मरीजों की मौत हुई थी.

डायरिया से पीड़ित इस व्यक्ति को एक हफ्ते में 100 से अधिक ग्लूगोज की बोतलें चढ़ानीं पड़ीं

डॉक्टर नॉर्बर्ट कहते हैं, "ताइवान और फिलीपींस में नौसेना के साथ तैनाती के दौरान भी मैंने सही नुस्खा बनाने की कोशिश की, लेकिन यह कुछ ज़्यादा ही गाढ़ा बन गया और चीज़ें और ख़राब हो गईं."
डॉक्टर नॉर्बर्ट ने बताया, "इस नुस्खे का आसान होना की इसका दुश्मन था. शिशुरोग विशेषज्ञों को यह समझाने में लंबा समय लग गया कि यह सुरक्षित है."
ब्रिटेन की स्वास्थ्य पत्रिका लांसेट और यूनिसेफ़ ने इसे स्वास्थ्य क्षेत्र में बीसवीं सदी की सबसे उम्दा खोज बताया है, जिसने बेहद सस्ती होने के बावजूद हर साल लाखों जीवन बचाई है.

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How does a fluorescent starter work?

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A fluorescent light does not have the usual glowing filament of an incandescent bulb, but instead contains a mercury vapor that gives off ultraviolet light when ionized. The ultraviolet light makes particles that coat the inside of the tube, and these particles glow or fluoresce (see How Fluorescent Lamps Work for details).
Fluorescent starters are used in several types of fluorescent lights. The starter is there to help the lamp light. When voltage is applied to the fluorescent lamp, here's what happens:

1. The starter (which is simply a timed switch) allows current to flow through the filaments at the ends of the tube.
2. The current causes the starter's contacts to heat up and open, thus interrupting the flow of current. The tube lights.
3. Since the lighted fluorescent tube has a low resistance, the ballast now serves as a current limiter.

When you turn on a fluorescent tube, the starter is a closed switch. The filaments at the ends of the tube are heated by electricity, and they create a cloud of electrons inside the tube. The fluorescent starter is a time-delay switch that opens after a second or two. When it opens, the voltage across the tube allows a stream of electrons to flow across the tube and ionize the mercury vapor.
Without the starter, a steady stream of electrons is never created between the two filaments, and the lamp flickers. Without the ballast, the arc is a short circuit between the filaments, and this short circuit contains a lot of current. The current either vaporizes the filaments or causes the bulb to explode.
According to Sam's F-Lamp FAQ:

The most common fluorescent starter is called a "glow tube starter" (or just starter) and contains a small gas (neon, etc.) filled tube and an optional radio frequency interference (RFI) suppression capacitor in a cylindrical aluminum can with a 2 pin base. While all starters are physically interchangeable, the wattage rating of the starter should be matched to the wattage rating of the fluorescent tubes for reliable operation and long life.

The glow tube incorporates a switch which is normally open. When power is applied, a glow discharge takes place which heats a bimetal contact. A second or so later, the contacts close and provide current to the fluorescent filaments. Since the glow is extinguished, there is no longer any heating of the bimetal and the contacts open. The inductive kick generated at the instant of opening triggers the main discharge in the fluorescent tube. If the contacts open at a bad time, there isn't enough inductive kick and the process repeats.

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Absurd Creature of the Week: This Goofy Fish Poops Out White-Sand Beaches

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The parrotfish may or may not feed exclusively on algae. Probably does though. John Johnson

Ah, Hawaii. The resplendent luaus and awe-inspiring volcanoes. Tom Selleck and his mustache running around private-investigating stuff. The beautiful white-sand beaches made of fish poop.

More absurd creatures:

10-Foot Bobbit Worm Is Ocean’s Most Disturbing Predator

The Ferocious Bug That Sucks Prey Dry and Wears Their Corpses

This Marsupial Has Marathon Sex Until It Goes Blind and Drops Dead

Oh, that’s right. Your precious Hawaiian beach vacation was actually a frolic through epic amounts of doody. Specifically, the doody from a very special kind of critter: the parrotfish. You see, parrotfish are quite partial to the algae that grow on coral, and they gnaw it off with two impressive rows of fused, beak-like teeth (hence their name). Simply by chewing on reefs, a large Hawaiian parrotfish can ingest a coral’s calcium carbonate and poop out up to 800 pounds of sand each year, according to marine biologist Ling Ong of Hawaii’s SWCA Environmental Consultants. One Australian species, she notes, produces up to one ton per year.
And the parrotfish isn’t alone here. “In places like Hawaii, where we have very little terrestrial input of sand, almost all of our sand is of biological origin,” Ong said. “So I like to tell people that the sand you’re standing on in Hawaii has probably gone through the gut of something. It’ll have gone through the gut of a parrotfish, a sea urchin, some kind of worm.”

Parrotfish come in staggeringly beautiful colors, unless you’re color blind. In which case, you’ll have to just take my word for it. John Johnson

Parrotfish, though, serve a far more important purpose in their grazing. Algae is a major threat to corals, positively smothering them and stealing their precious light. Parrotfish play a huge role in keeping algae in check, though they can get a bit carried away. Some species have evolved to not only skim the algae off the top, but gnaw a few millimeters down to reach algae that has penetrated the coral. Overall, though, they’re the reef’s benevolent and indispensable gardeners.
Now, if you’re anything like me, you considered eating chalk at some point in your childhood. Luckily I never did—which isn’t to say I didn’t come close—because blackboard chalk used to be made of calcium carbonate, exactly what coral is made of. And when calcium carbonate mixes with acid, it fizzes like crazy. “It creates carbon dioxide,” said Ong. “So if you’re a regular animal and you had acid in your stomach and you ate a chunk of chalk, you would get fizzy quickly. It would be generating a lot of gas.”
So why aren’t parrotfish spontaneously exploding all over the reef? Well, they don’t have stomachs. They simply gnaw off the algae and calcium carbonate and grind it up with teeth at the back of their throat known as pharyngeal jaws (the same jaws, by the way, that the moray eel has evolved into horrifying forward-thrusting chompers like those in the queen from Alien). Their digestive systems then take up the nutritious algae while firing out the calcium carbonate as sand.

Mucus Sleeping Bags and Polychromatic Sex Changes

All of this beach-building is exhausting work, and indeed the parrotfish is a strangely heavy sleeper. Like, dangerously heavy. “They don’t wake up easily at all, which makes them fairly easy to catch,” said Ong, “because you can go down and shine a light at them and they’ll be sound asleep. And the ones you do catch, you put them in a dark bag and they go back to sleep.”
Ong isn’t sure why exactly they need such deep sleep, though it wouldn’t seem to make much evolutionary sense. Why leave yourself so vulnerable?
Well, younger, smaller parrotfish, which are of course more susceptible to predation, have a brilliant little trick. They tuck themselves into a crevice or under a ledge and secrete mucus to build a translucent, semi-solid sleeping bag, which balloons to encase the parrotfish in a water-filled bubble. It’s likely a measure to mask their scent from predators, or a kind of proximity sensor to detect when something is closing in. And when they wake up in the morning, they’ll recycle the cocoon by eating it for breakfast. Try doing that with your sleeping bag the next time you go camping.

A parrotfish demonstrates the world’s most ineffective force field. John Johnson

But their heavy sleep makes the larger individuals extremely vulnerable to spearfishers, who target the easy prey at night. And while losing an individual parrotfish every once in a while to fishing may not seem like a huge deal, the way parrotfish societies are set up makes this kind of hunting a serious threat.
You see, most parrotfish species are sex-changers. Individuals are born female and form into schools. Once they’ve matured, the largest female will change into a male, assuming rule over the school, which essentially becomes his harem. He begins managing territory, chasing away rival males, and transforms his drab skin into the gaudy colors in the photos above.
Yet this color shift doesn’t happen every time. Some males eschew the lovely new outfit in favor of a more sneaky strategy: They pretend to still be female. “So when it comes to spawning, they can sneak in,” said Ong. “When the males and females spawn—either in the territory, or some of them actually congregate in a place and they group-spawn—the sneaker males can insert themselves in there. And there are a fair number, so it’s a reproductive strategy that must work.” (The giant Australian cuttlefish actually does the same, with males manipulating their arms to look like females, sneaking under dominant males to steal a kiss with their mates, and by steal a kiss I mean hand her bundles of sperm.)

If you’re going to sleep like a rock, you may as well look like one too. John Johnson

Now, it’s great being the big man on campus—until a bigger bully shows up. “This is a fish that a lot of Pacific Islanders like to eat,” said Ong. “And normally they target the biggest fish, and that causes a problem for these kinds of sex changes, because you’re taking a lot of the males out of the population. And you’re also taking a lot of the big females out of the population, and they’re the ones that are creating the most young.”
Indeed, the creatures are overfished in most parts of the world, setting off a domino effect that leaves coral, already struggling to survive climate change, at the mercy of algae. And interestingly, according to Ong, parrotfish seem to be getting smaller. Could we be artificially selecting against the largest individuals by removing them from the gene pool? After all, we seem to have done the same with elephant tusks, poaching individuals with the most ivory and keeping them from passing along their genes for such size.
Really, it’s no way to treat such a wonderfully bizarre fish, much less a creature that’s building our beaches free of charge. So the next time you’re lounging in the sands of Hawaii, take a moment to appreciate the parrotfish, which only ever wanted to gnaw on coral and sleep in its own snot, and maybe, if it’s lucky, undergo a sex change. And if that’s not one hell of an iconoclastic life, I don’t know what is.

(got on bbc)

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Fantastically Wrong: Why the Guy Who Discovered Uranus Thought There’s Life on the Sun

You can’t live on the sun. Well, you can try if you want. I’m not your mother. NASA

There are a whole lot of places in the universe that aren’t exactly conducive to the proliferation of life: the vacuum of space, for instance, or the poisonous, boiling atmosphere of Venus, or anywhere Chuck Norris goes. But surely the most brutal are the unimaginably hot surfaces of stars like our sun, furnaces so powerful that they fling energy billions of miles.

Fantastically Wrong

It's OK to be wrong, even fantastically so. Because when it comes to understanding our world, mistakes mean progress. From folklore to pure science, these are history’s most bizarre theories.

Browse the full archive here.

Sure, we know that now. But in 1795, prominent astronomer William Herschel, who had discovered Uranus 14 years previous, took the opposite view. In the essay “On the Nature and Construction of the Sun and Fixed Stars,” he argued that the sun is simply an enormous planet, and because all other planets in our solar system contain life (a popular opinion in his day), so too must our star. It sounds mad, but he put forth sophisticated arguments to bolster his theory.
But first, a bit of background on the years leading up to Herschel’s bold claim. The telescope was invented in the early 1600s, and was first turned skyward not by its inventors, who were concerned with more terrestrial applications (“seeing faraway things as though nearby,” as one patent application read), but by Galileo. Observations of the sun began almost immediately, and what followed was a sort of stargazing gold rush, as inventors developed ever more powerful devices, while of course remaining cautious not to burn their eyeballs out of their heads.

William Herschel, the discoverer of Uranus, believer of life on the sun, disapprover of paragraphs above and to the left of his person. Wikimedia

By the 1700s, astronomers observing sunspots hit upon an idea: The sun was a regular old terrestrial planet like ours that just happened to be covered with a luminous atmosphere. One Englishman figured that such sunspots were volcanoes belching smoke through glowing gas, while another reckoned they were towering mountains peeking through, according to Steven Kawaler and J. Veverka in their essay “The Habitable Sun: One of William Herschel’s Stranger Ideas.” Another figured the bright, hot matter wasn’t an atmosphere but an ocean, and that sunspots were instead mountains exposed by ebbing tides.
In reality, sunspots are areas where the star’s magnetic field becomes highly concentrated, inhibiting convective motion and therefore the transport of heat, dropping the temperature inside to thousands of degrees cooler than the rest of the surface. It’s still quite bright (if you could pull one out of the sun it’d glow brighter than a full moon), but in contrast to the surrounding hotter areas it appears dark. And that apparent ebbing tide exposing and enveloping mountains? It’s actually the sun’s shifting magnetic field opening up and closing new spots willy-nilly.
Anyway, along comes Herschel, who subscribes to the idea that sunspots can be either openings in the atmosphere exposing land or mountains rising above the luminosity. Scaling up the potential size of mountains on the sun using a mountain on Earth with a height of 3 miles, he gets a potential height of 334 miles, adding that “there can be no doubt but that a mountain much higher would stand very firmly”—unlike his theory as a whole, appropriately enough.

Sunspots utilize the time-tested buddy system, opening up in pairs as the sun’s magnetic field comes out of one and dives back into another. NASA

As to how the atmosphere formed in the first place, Herschel invokes the formation of clouds on Earth, “but with this difference, that the continual and very extensive decompositions of the elastic fluids of the sun, are of a phosphoric nature, and attended with lucid appearances, by giving out light.” But why hasn’t the sun exhausted its supply of “elastic fluids” that throw so much energy into space? Just as clouds rain water back down to Earth, “in decomposition of phosphoric fluids every other ingredient but light may also return to the body of the sun.” I mean, could you imagine it raining light? That’d just be silly.
According to Kawaler and Veverka in their essay, “it is clear that what especially attracted Herschel to this model of the sun were its philosophical implications,” since it brought the sun in league with other planetary bodies. “Clearly,” they add, “it is a product of Herschel’s prejudice that all planets are inhabited.”

It’s Getting Hot in Here, So Take Off All Your Preconceived Notions of Where Life Can Potentially Exist

It was prejudice that of course came with problems, both scientifically and existentially. While Herschel believed the sun to be inhabited “by beings whose organs are adapted to the peculiar circumstances of that vast globe,” at the same time he pointed out that “angry moralists” thought the star to be “a fit place for the punishment of the wicked,” while “fanciful poets” reckoned it was home to blessed spirits. Clearly not all parties could inhabit the same world without stepping on each other’s toes.
And then there was the question of how the luminous atmosphere wouldn’t simply cook any life on the sun. Herschel argued that “heat is produced by the sun’s rays only when they act upon a calorific medium.” Substances that can be heated, you see, contain the “matter of fire,” as a flint can ignite gunpowder that already contains such fire. If light alone could cause heat, he reasoned, then you’d expect the top of our highest mountains, where light’s course is the least interrupted, to be quite hot indeed, when in fact they’re frigid. And because the sun emits such an incredible amount of light, it stands to reason that little of it is acting upon such a “calorific medium” to produce heat on the surface. There must be something chemically different about the surface and atmosphere of the sun.
According to Kawaler and Veverka, six years after he proposed this theory, Herschel returned with another reasoning of how life on the sun would keep from bursting into flames. The sun must have not just a luminous atmosphere, but an underlying layer of clouds so opaque that they bounce the light into space, protecting the inhabitants below.

Hans Bernhard/Wikimedia

The scientific community, however, wasn’t buying it. The polymath Thomas Young reckoned that not only would the cloud layer be totally worthless at reflecting heat, no matter how dense it was, but there also was the rather glaring problem of gravity. Living beings on such a large body would be flattened like Wile E. Coyote beneath an anvil—my words, not his. And in 1821, David Brewster, also a polymath (Europe was lousy with them back then), instead attacked the very core of Herschel’s reasoning: He’d based his theory on the assumption that the sun was like any other planet and would therefore harbor life, when the sun was in fact unique in our solar system.
And in 1801, the collapse of a building in Germany led humanity to see the sun in a totally new light. Joseph von Fraunhofer, an orphan and decidedly not a polymath, was trapped when the mirror and glass shop he apprenticed in crumbled. The crowd that gathered to witness the ensuing rescue included Prince Elector Maximilian Joseph IV, who took pity on von Fraunhofer, providing him cash and books to further his studies. Von Fraunhofer eventually made huge advances in lens-making and, more importantly for astronomy, invented the spectroscope, which was later used to determine the chemical makeup of the sun by analyzing its light.
What we then began to understand is that instead of featuring a surface for life to amble around upon, the sun is in fact comprised of hydrogen and helium gas. And later on in the early 20th century, scientists finally solved the mystery of the sun’s power: It is, as They Might Be Giants noted, a gigantic nuclear furnace. Specifically, it’s a nuclear fusion furnace, in which hydrogen atoms collide to produce not only helium, but astounding amounts of energy and sunburns on Earth.

Joseph von Fraunhofer shows off his fancy spectroscope to—if you can believe it—old white men.
Wikimedia

So our sun never has been and never will be home to life. But Herschel’s rather far-fetched theorizing ignited a debate that furthered our understanding of the star. And his kind of thinking—imagining what it would take for beings to proliferate on other worlds—echoes today in our quest to find life elsewhere in our solar system and beyond. While not as fanciful as Herschel’s thinking, scientists have proposed, for instance, that methane-based life could find a home on a planetary body like Saturn’s moon Titan.
There’s also vast clouds of alcohol in space, by the way. Could life be floating around drunk in there? We’ll never know until someone foots the bill for putting me in a rocket to go and investigate. So please. Please someone put me in a rocket so I can go investigate.
References:
Herschel, W. (1795) On the Nature and Construction of the Sun and Fixed Stars. Philosophical Transactions of the Royal Society of London. 1795-01-01. 85:46–72
Kawaler, S. and Veverka, J. (1981) The Habitable Sun: One of William Herschel’s Stranger Ideas. Journal of the Royal Astronomical Society of Canada. Vol. 75, P. 46
(got on bbc )

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शीशे की तरह दिखेंगे शरीर के अंग

वैज्ञानिकों ने एक ऐसी तकनीकी विकसित की है जिससे पूरा शरीर शीशे की तरह पारदर्शी हो सकता है.

'सेल' नाम की विज्ञान पत्रिका में प्रकाशित रिपोर्ट में वैज्ञानिकों ने इस तकनीक की जानकारी दी है.

वैज्ञानिकों का कहना है कि इस तकनीक से शरीर को कोई नुक़सान नहीं पहुँचता है लेकिन शरीर के सभी  अंगों को देखा जा सकता है.
इससे यह जानने में मदद मिलेगी कि शरीर के विभिन्न  अंग काम कैसे करते हैं.

पढ़ें पूरी रिपोर्ट

अभी तक चूहों और गिलहरी जैसे स्तनपायी जानवरों पर इसका प्रयोग किया गया है लेकिन इसका प्रयोग मानव शरीर में विषाणुओं के प्रसार और कैंसर का पता लगाने में भी किया जा सकता है.
क़रीब एक सदी से वैज्ञानिक शरीर को पारदर्शी रूप से देखने का प्रयास कर रहे थे लेकिन अधिकांश तकनीकें उत्तकों को नुक़सान पहुंचा सकती हैं.
कोशिकाओं में मौज़ूद लिपिड (वसा) के मोटे कण प्रकाश किरणों को विकृत कर उत्तकों को अपारदर्शी बना सकते हैं लेकिन उन्हें विघटित करने में प्रयोग होने वाली प्रक्रिया से  अंग कमज़ोर हो सकते हैं और उनका आकार बिगड़ सकता है.

कैलिफ़ोर्निया इंस्टीट्यूट ऑफ़ टेक्नोलॉजी के वैज्ञानिकों ने पूर्व के वैज्ञानिक कामों के आधार पर एक तीन स्तरीय तकनीक विकसित की है.

• एक नरम प्लास्टिक की झिल्ली उत्तकों को सहारा देती है.
• ख़ून के प्रवाह के ज़रिए आनुवांशिक डिटर्जेंट (साफ़ करने वाले पदार्थ) को लगातार डाला जाता है. यह लिपिड को घोलता जाता है और अंगों को पारदर्शी बनाता जाता है.
• महत्वपूर्ण जोड़ों को पहचानने के लिए इस मिश्रण में पहचान करने वाले रंगों और अणुओं को मिलाया जा सकता है.

इस विधि का चूहों और गिलहरियों में प्रयोग कर वैज्ञानिक उनकी  किडनी, दिल, फेफड़ों और आंतों को तीन दिन में देखने में सफल रहे. उन्होंने दो हफ़्ते में उनके पूरे शरीर को पारदर्शी रूप से देख लिया.

वैज्ञानिकों का सपना

रिपोर्ट के प्रमुख लेखक डॉक्टर विवियाना गार्डिनारू कहते हैं कि यह जीव वैज्ञानिकों के सपनों को सच करने जैसा है.
वो कहते हैं कि स्कैनिंग तकनीक की मदद से डॉक्टरों को शरीर को देखने में मदद मिल रही है. लेकिन वो यह नहीं जान पा रहे है कि कोई कोशिका या उत्तक कर क्या रहे हैं. मगर इस तकनीक के ज़रिए शरीर के उन अंगों की पहचान और उनके काम की प्रामाणिक जानकारी जुटाई जा सकती है, जिसके बारे में हम जानकारी हासिल करना चाहते हैं.

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कुदरत के बनाए पांच असाधारण इंद्रधनुष

कल्पना कीजिए उस दुनिया की जहां रंग-बिरंगे पहाड़ मौजूद हैं.
चीन में उत्तर-पश्चिमी गंसू प्रांत ऐसी ही जगह है जहां 2.4 करोड़ वर्ष से खड़े हैं ऐसे ही पहाड़ जो अपने भीतर छिपाए हुए हैं कई तरह के खनिज पदार्थ.

क्या इन पहाड़ों को देखकर ऐसा नहीं लगता कि इन्हें किसी ने बाक़ायदा कूची लेकर रंगा है!
इन्हें रंगा तो गया है लेकिन ये किसी इंसान का नहीं बल्कि कुदरत का कमाल है. जगह है अमरीका का ओरेगन राज्य.

ये है ज़मीन के भीतर मौजूद पानी, सल्फर, आयरन ऑक्साइड, नमक और अन्य लवणों से मिलकर बनी दिलकश झील जो दरअसल एक ज्वालामुखी का क्रेटर यानी उद्गम है.
जगह है अफ्रीका का इथियोपिया देश.

ये है अमरीका में गर्म पानी का सबसे बड़ा सोता जहां पानी का तापमान ही तय करता है रंगों की चटक जो हर साल लाखों पर्यटकों को अपनी ओर आकर्षित करती है.

इस नज़ारे को देखने के लिए आपको आइसलैंड तक जाने की ज़रूरत नहीं है.
विज्ञान ने इन आसमानी रंगों को समझने की बहुत कोशिश की है लेकिन कुछ रहस्य अभी तक रहस्य ही हैं.

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चाँद का मुँह टेढ़ा क्यों है?

वैज्ञानिकों ने इस बात का पता लगाया है कि हमारे चाँद का आकार बिगड़ा हुआ-सा क्यों है.

एक अमरीकी रिसर्च टीम ने इस बात की गणना की है कि ज्वार-भाटा और उसकी धुरी पर घूमने की गति ने चंद्रमा के आकार को प्रभावित किया है.

 नेचर पत्रिका में छपे लेख में उन्होंने कहा है कि चंद्रमा की अपनी ही धुरी पर घूमने की रफ्तार और ज्वार-भाटा के कारण हमारे उपग्रह का आकार नींबू की तरह हो गया है.
रिसर्च टीम के लीडर और यूनिवर्सिटी ऑफ़ कैलिफ़ोर्निया सांता क्रूज़ से जुड़े प्रोफ़ेसर गैरिक बेथेल ने बताया कि चाँद के आकार ने तब स्वरूप लेना शुरू किया जब उसका अधिकतर हिस्सा तरल था.
इस तरल हिस्से के चारों तरफ बाहर से चट्टानों की एक पतली सी सतह थी.

धरती के प्रभाव के कारण ही चाँद अपनी धुरी पर थोड़ा सा झुका हुआ है.
उन्होंने बताया, "पृथ्वी, मंगल और ऐसी ही अन्य खगोलीय चीजों के बारे में हम जानते हैं कि इनका आकार इनकी इसी रफ्तार की वजह से है."
"अगर आप पानी से भरे किसी बैलून को घुमाना शुरू करते हैं तो यह भूमध्य रेखा की ओर उभर जाएगा और धरती पर भी ऐसा ही कुछ होता है."

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ExoMars’ Organic Sniffing Spectrometer

An artist’s rendering of the ExoMars rover.  European Space Agency

Lewis Dartnell spent the better part of two years researching and field-testing methods to reboot society in his best-selling book The Knowledge. But his day job is arguably even cooler: as an astrobiologist at the University of Leicester, he’s developing ways to look for life on Mars through the European Space Agency’s ExoMars mission. Here, Dartnell provides an update on the frequently delayed, yet scientifically promising mission.
Wired: In The Knowledge, you incorporate ideas and methods from many different branches of science. How does this kind of interconnectedness show up in your own work?
Dartnell: Drawing from lots of different sources is what I do in my own research in astrobiology, and not just knowledge, but the methods and techniques you could use. It’s not just biology, but engineering, and robotics and instruments as well as physics and planetary science, and you’re constantly outside of your comfort zone having to learn new things. It keeps you on your toes, but that’s what I enjoy about astrobiology.
Wired: What is your role with the ExoMars mission?
Dartnell: The exciting thing about ExoMars is that, not only will it for the first time have a drill so it can get properly underground on Mars and find stuff that has been protected from the surface environment, but it’s also going to use experiments like Raman spectroscopy, which is the one that I’m directly involved in at the University of Leicester. The reason Raman’s exciting is that it’s very sensitive and very competent and capable of picking up organic molecules or bio signatures of life, and we want to try this new technique on Mars.
Wired: What are your expectations for ExoMars?

Dartnell: We don’t know, and that’s the point of exploration; you don’t always know what you’re going to try and find. You know what you’re hoping for, and what might be realistic to expect. So what we hope to find on Mars are organic molecules – the basic Lego pieces or building blocks or chemistry kit for life; amino acids and sugars that should exist on Mars but we have yet to discover. Hopefully either NASA’s Curiosity or ESA’s ExoMars will discover those, and maybe beyond that they’ll find not just the building blocks for life but signs of life itself – biosignatures.
Wired: What kinds of biosignatures would be convincing as a sign of past life?
Dartnell: A biosignature is any sign or any evidence of life, and this might be something like a fossilised shape that looks a bit like a cell, it might be things as complex as DNA. It might be more subtle things like isotopic ratios in rocks, which on Earth are used to show early cases of life. Or if we do find things like amino acids, we can tell if they are made by life or through non-living processes like pre-biotic chemistry by their molecular handedness. So there are various quirks or various signs of organic molecules we can look for that would point to biology, rather than geochemical processes.
Wired: What is the likelihood that you will find biosignatures on Mars?
Dartnell: Unfortunately, you basically can’t answer that question. It’s somewhere between 0 and 1, but we don’t know because whenever you’re trying to do something in science you’re trying to do something new that you don’t already know the answer to,
However, for all we know about life on Earth, it seems to have arisen pretty rapidly. It seems like it might be a probable thing to happen, if you’ve got the right kind of environment. So the big question is whether Mars ever have the right kind of environment, and if so, did that basic pre-biotic chemistry ever get far enough down the line to produce cells? And if that happened, what might be the best way of looking for that life and trying to detect these biosignatures? Which biosignatures would still remain after all this time? This is the kind of thing we’re trying to do with ExoMars.

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The Oculus Rift Made Me Believe I Could Fly

Birdly is a full-body flight simulator integrating the Oculus Rift.  Joshua Batson/WIRED

Yesterday, I flew over downtown San Francisco. I swooped past the Transamerica Pyramid, taking care not to get speared, and winged it out towards the water. A heavy fog covered the bay, as usual, so I decided to head back into the city. I dove sharply, and the wind started whipping across my face. I slipped under the Bay Bridge, banked hard and promptly slammed into a warehouse. The wind died, and my screen went black.
I was strapped into Birdly, a full-body flight simulator designed to make you forget you’re not a bird. “Press the red buttons and pump your arms to start soaring again,” said Max Rheiner, the Swiss artist responsible for my in-flight experience this week at Swissnex. (Birdly flew here from its birthplace at the Zurich University of the Arts.) The reason that Rheiner could make this simulator now, and not 20 years ago when he first dreamed of helping humans feel like birds, is the arrival of the Oculus Rift. The Rift is the first virtual reality headset with two key features: It’s cheap, and it doesn’t make you want to vomit. Now that there’s a way to provide accurate head-tracking at low enough latency to prevent motion sickness, people who were raised on the promise of virtual reality are starting to experiment.
Humans dreamed of flying like a bird for centuries before hot air balloons finally took people into the skies. At first the designers of Birdly took the dream a bit too literally and used a physics engine to model airflow around virtual wings. But it turns out to be hard for humans to fly like an actual bird, learning to flap their wings at the right angle and catch thermals to spiral up. To simulate the effortlessness of dream flight, Rheiner made the interface more metaphorical and intuitive. By twisting your arm you control the pitch of the wing: Tip up to soar higher, and tip down to dive. Catch the air with one hand to bank. To climb faster, you can vigorously pump both wings. Pistons provide realistic resistance, and a fan is calibrated to make the windspeed match your virtual velocity.

Climb on! Joshua Batson/WIRED

It’s admittedly a bit awkward to climb onto Birdly. You bend over a padded frame, strap on a tight headset and headphones, then hook your hands into wooden wings. But then the screen flips on and you find yourself floating above the city, watching your bird-shadow drifting across the rooftops. If you crane your neck, you can see your brown feathers ruffling in the breeze. After a few seconds, flying feels natural.
The individual components of the system are still a bit rough, but together they provide an amazing experience. The screen on the Rift was more pixellated than my smartphone, and I had to move my head slowly to keep the landscape in sync. If this were only a visual tour of the San Francisco skyline, I might have gotten a bit nauseated. But just like the driver of a car almost never feels nauseated even when the passengers in the backseat are clutching their stomachs, I felt comfortable because of the tactile control and physical feedback. I feel like Birdly managed to just get past some threshold of pleasurability and plausibility, so that I wanted to keep flying all night. It also made me impatient to race around faster, diving and swooping and barrel rolling. I wanted to fly over the rest of California, and to see it all with perfect resolution.
Given that Birdly was made by a team of just three people working part-time since receiving a Rift development kit in November, I expect that progress will be swift. For example, the experience will soon include smells. Rheiner, working with a Dutch fragrance designer, built a rig to emit little pumps of scented alcohol as you fly. But a realistic cityscape has to include hot asphalt and car exhaust, and it’s tricky to deliver a whiff of those that won’t knock you out of the sky.
While Rheiner’s team was aiming for art, there might also be a future in travel and fitness. Imagine spending an afternoon flying through the Grand Canyon—a beautiful trip, and if you need to flap your wings the whole time to stay aloft, a serious work out. Before a walk to your basement can replace a helicopter ride in Hawaii, though, a compendium of detailed 3-D maps would be required. Promisingly, Google Earth sent 20 people to visit Birdly last week.
An interface like Birdly’s could some day be used to fly a real drone in realtime, says Rheiner. You could fly wherever you want and see what’s happening there right now, no mapping necessary. You could take a trip to check out the forest fires raging in Northern California, or circle a friend’s outdoor BBQ like a (creepy) vulture. Using your body to control a drone would also obviously be more fun than using a joystick, and might be safer too. The more you identify with the drone, the more you feel its body as your own, the better your reflexes could be. If a plane zooms into your peripheral vision, you’ll flap your wings instead of dropping the controller.
Today there is only one Birdly prototype. If you want to ride it, you have to catch the machine next week in San Francisco (at Swissnex or the Exploratorium) or at the SIGGRAPH conference in Vancouver from August 10-14. But don’t worry too much if you miss it. Birdly is less a definitive experience than an argument that, at last, we have all the pieces necessary to make an engaging full-body simulation. So if you would rather swim like a dolphin or squirm like a snake than fly like a bird, just wait a bit. The consumer version of the Rift should be out in about a year. Meanwhile, In companies and universities and studios around the world, designers are starting to make your dream a (virtual) reality.

 

content is picked from wired.com

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पेपर की तरह मोड़ सकेंगे टीवी को?

इलेक्ट्रॉनिक उत्पाद बनाने वाली कंपनी एलजी ने पेपर जैसे पतले दो नए टीवी स्क्रीन लॉन्च किए हैं जिनमें से एक इतना लचीला है कि उसे तीन सेंटीमीटर की गोलाई में मोड़ा जा सकता है.

 कंपनी का कहना है कि इसके ज़रिए अब टीवी को नई तरह से इस्तेमाल किया जा सकेगा.

इस नए टीवी स्क्रीन का रेज़ोल्यूशन 1,200x810 है जिसकी वजह से इसे मोड़ने के बाद भी तस्वीरें बिगड़ती नहीं.
कंपनी को विश्वास है कि 2017 तक वो इसके ज़रिए 60 इंच का मुड़ने वाला टीवी बनाने में कामयाब होंगे.

स्टफ़ टीवी के संपादक स्टीफ़न ग्रेव्स के मुताबिक, "मुड़ने वाली स्क्रीन एक बेहतरीन तकनीक है जो नए रास्ते खोलती है. ये परंपरागत स्क्रीन से ज्यादा टिकाऊ होगी. इसका मतलब है कि हम हवाई जहाज़ जैसी जगहों पर बड़ी और बेहतर स्क्रीन की उम्मीद कर सकते हैं."
कंपनी ने इस साल की शुरूआत में अपने पहले 'लचीले टीवी' की घोषणा एक इलेक्ट्रॉनिक्स ट्रेड शो में की थी.

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दवा प्रतिरोधी मलेरिया का ख़तरा

दक्षिण पूर्वी एशिया में दवा-प्रतिरोधी मलेरिया का तेज़ी से प्रसार हो रहा है और अब यह कंबोडिया-थाईलैंड सीमा तक पहुंच गया है.

वैज्ञानिकों का कहना है कि दवा-प्रतिरोधी मलेरिया को रोकने के लिए "कड़े कदम" उठाने की ज़रूरत है.

वैज्ञानिकों ने  'न्यू इंग्लैंड जर्नल ऑफ़ मेडिसिन' में बताया है कि मलेरिया के बढ़ते मामलों से मलेरिया नियंत्रण के प्रयासों को गहरा झटका लगा है.

प्रतिरोधक क्षमता

एक अध्ययन में एशिया और अफ़्रीका के 10 देशों के 1000 मलेरिया मरीजों के खून के नमूनों का परीक्षण किया गया था.
इसमें पाया गया कि पश्चिमी और उत्तरी कम्बोडिया, थाईलैंड, वियतनाम और पूर्वी म्यांमार में परजीवियों ने मलेरिया के सबसे प्रभावकारी दवा अर्टीमिज़ीनिन्स के ख़िलाफ़ प्रतिरोधक क्षमता विकसित कर ली है.
हालांकि अफ्रीका के तीन देशों केन्या, नाइजीरिया और कांगो में प्रतिरोधी मलेरिया के साक्ष्य नहीं मिले.

यूनिवर्सिटी ऑफ़ ऑक्सफ़ोर्ड के प्रोफेसर निकोलस व्हाईट ने कहा, "प्रतिरोधक मलेरिया का असर दक्षिण पूर्वी एशिया के अधिकांश हिस्से में है. हम जितना उम्मीद करते थे, यह उससे भी बदतर है. इस दिशा में कुछ करना है तो हमें जल्दी कार्रवाई करनी होगी.''
उन्होंने कहा, ''आगे इसके प्रसार को रोकना बहुत हद तक संभव है, लेकिन मलेरिया नियंत्रण के परंपरागत तरीके पर्याप्त नहीं होंगे. हमें और अधिक कड़े कदम उठाने की ज़रूरत है और बिना देरी किए इसे दुनिया भर में सार्वजनिक स्वास्थ्य के क्षेत्र में तरजीह देने की ज़रूरत है."

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क्या हमें भविष्य के रोबोट से डरना चाहिए?

तकनीकी विषयों की दुनिया की सबसे पुरानी पत्रिका एमआईटी टेक्नॉलॉजी रिव्यू ने 2011 में विज्ञान की काल्पनिक कहानियों पर आधारित एक अंक निकाला था.

पत्रिका के मुताबिक़ इस अंक का उद्देश्य नई तकनीकों की पहचान करना और उन तकनीकों का हमारे जीवन पर पड़ने वाले प्रभावों की पड़ताल करना था.

इससे पहले भी विज्ञान गल्प या सांइस फ़िक्शन की कहानियों में इस तरह की उल्लेखनीय काम की परंपरा रही है.

1937 में एमआईटी ग्रेजुएट ने जॉन कैंपबेल ने एसटॉउंडींग स्टोरीज़ मैगज़ीन का संपादन किया था और उसका नाम बदलकर एसटॉउंडींग साइंस फ़िक्शन कर दिया था.
इसमें विश्वसनीय लगने वाले पात्रों और विज्ञान की कल्पनाओं पर ज़ोर दिया गया था.
ऐसी ही चौंका देने वाली एक कहानी हिरोशिमा बम विस्फोट की घटना से एक साल पहले की है जिसमें परमाणु बम बनाने की बात का उल्लेख हैं.

भविष्य का सामाजिक संवाद

लेकिन भविष्य का आकलन करना मुश्किल है और अक्सर यह ग़लत साबित होता है. इसका यह मतलब नहीं कि यह एक बेकार काम है.
साइंस फ़िक्शन लेखक रॉबर्ट सेवयर 2003 में साइंस फ़िक्शन के सबसे बड़े पुरस्कार ह्यूगो अवार्ड के विजेता है.
उनका कहना है कि उनका काम भविष्य के सामाजिक संवादों की पड़ताल करना है.
राबर्ट सेवयर कुछ ऐसी बातों को लेकर बहुत आशान्वित हो जो लोगों के लिए चिंता का विषय है मसलन भविष्य की ऊर्जा संबंधी ज़रूरतें भी इनमें से एक हैं. वह अपने विज्ञान गल्प के लेखनीय दृष्टि से ऊर्जा के सतत स्रोतों का भविष्य में इतना विस्तार होते हुए देखते हैं कि ऊर्जा संसाधनों की क़ीमत लगभग शून्य हो जाएगी.

इसबीच अमरीका के साइंस फ़िक्शन लेखक रे कुर्जवेल 2050 की स्थिति का आकलन करते हैं जब कृत्रिम बुद्धिमता मानवीय बुद्धिमता की जगह ले लेगा.
सेवयर कहते हैं, "जब हमारे पास हमारी बुद्धिमता के बराबर और दोगुनी बुद्धिमता का मशीन होगा तो कोई कारण नहीं है कि मशीन और इंसान के बीच का यह रिश्ता सहक्रियाशिलता के बदले विरोधाभासी हो जाए."
वह आगे कहते हैं कि लोगों के लिए डर का सबसे बड़ा कारण है कि भविष्य में उसका सामना एक ऐसे बुद्धिमान रोबोट से होने वाला है जो विलक्षण बुद्धिमता वाला होगा और वह इंसान नहीं होगा लेकिन इंसानी आकांक्षाओं वाला होगा.

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