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Hidden life of the cell
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Researchers at the Salk Institute have discovered a toggle switch for aging cells. By controlling the growth of telomeres, it may eventually be possible to coax healthy cells to keep dividing and generating even in old age.
The cells in our bodies are constantly dividing, replenishing our lungs, skin, liver, and other organs. Regrettably, most human cells can’t keep on dividing forever. Each time a cell divides, a cellular “timekeeper” at the ends of the chromosomes shortens. These timekeepers, called telomeres, are like the aglets at the end of your shoelaces — those important bits of plastic that prevent the lace ends from fraying. But in the case of shortened telomeres, cells are no longer able to divide, resulting in a host of aging-related complications, including organ and tissue degeneration.
Patching the Ends – Back in 1973, Soviet biologist Alexey Olovnikov predicted the existence of a “fix” or compensatory mechanism for this process. Scientists Carol Greider and Elizabeth Blackburn were awarded the Nobel Prize in 1984 by proving him right. Their team discovered that some cells produce an enzyme called telomerase, which rebuilds telomeres and allows cells to divide indefinitely. This enzyme — which carries its own template (in the form of an RNA molecule) to elongate the telomeres — adds DNA sequence repeats to the end of DNA strands in the telomere regions. Think of them as disposable buffers that block the ends of chromosomes.
Aging, therefore, was thought to arise from a lack of telomerase — but it now appears that telomerase activity is a bit more complicated than that.
The new research shows that telomerase has a kind of toggle switch, and if the switch happens to be flipped to the “off” position, merely having adequate levels of telomerase in our cells may simply not be enough. The research team of Vicki Lundblad and Timothy Tucey discovered that telomerase — even when present — can be turned off, or disassembled. That’s a huge deal because an understanding of how this “off” switch can be manipulated — thereby slowing down the telomere shortening process — could eventually lead to treatments for an assortment of aging-related diseases. For example, the regeneration of vital organs later in life. More here Cellular Toggle Switch Could Herald An Anti-Aging Breakthrough.
In the quantum world, there’s no such thing as just a “particle”. Each particle is also a wave, and can interfere with itself. In this latest episode of The Quantum Around You Associate Professor Andrea Morello, describes why quantum mechanics has more of an impact on your daily life than you think. – Deskarati
Alan Mason tells us an interesting story of Michael Faraday’s early history.
It is not widely known that Faraday’s career rests on the outcome of a drunken brawl. He was an apprentice bookbinder and sometimes served in the bookshop attached. A customer saw he was a bright lad and gave him tickets for a series of lectures by Davy on science. Faraday attended all the lectures, took notes and bound the notes into a small book. He wrote to Davy, enclosing the notes as an indication of his interest and enthusiasm, asking if there were any jobs available at the Royal Institution presided over by Davy. As it happened, Davy already had a lab technician, but he was off work with a broken arm, as a result of a Saturday night brawl when he was drunk. Davy invited Faraday to come and see him, and the rest is history.
There was little need, before, to know exactly how much dust peppers outer space, far from the plane of the Milky Way. Scientists understood that the dimly radiating grains aligned with our galaxy’s magnetic field and that the field’s twists and turns gave a subtle swirl to the dust glow. But those swirls were too faint to see. Only since March, when researchers claimed to have glimpsed the edge of space and time with a fantastically sensitive telescope, has the dust demanded a reckoning. For, like a cuckoo egg masquerading in a warbler’s nest, its pattern mimics a predicted signal from the Big Bang.
Now, scientists have shown that the swirl pattern touted as evidence of primordial gravitational waves — ripples in space and time dating to the universe’s explosive birth — could instead all come from magnetically aligned dust. A new analysis of data from the Planck space telescope has concluded that the tiny silicate and carbonate particles spewed into interstellar space by dying stars could account for as much as 100 percent of the signal detected by the BICEP2 telescope and announced to great fanfare this spring. More here ‘Big Bang Signal’ Could All Be Caused by Dust, Planck Team Says
It’s the birthday of Michael Faraday, who was born in 1791 in Newtington Butts, a village that is now part of south London. Faraday gained his scientific education as an apprentice to the chemist, Humphrey Davy – and went on the surpass his mentor in both chemistry and physics. Among his achievements in chemistry are the discovery of benzene and the formulation of laws of electrolysis. In physics, he discovered electromagnetic induction, diamagnetism and introduced the concept of lines of force. Faraday was also a devout Christian. He declined a knighthood and refused to help the British government develop chemical weapons during the Crimean War. On 19 March 1849 he wrote in his laboratory journal, “ALL THIS IS A DREAM. Still examine it by a few experiments. Nothing is too wonderful to be true, if it be consistent with the laws of nature; and in such things as these experiment is the best test of such consistency.” Via Facebook.
Eating artificial sweeteners may spur the very health problems that dieters try to avoid. A new multipronged study of mice and a small number of people finds that saccharin meddles with the gut’s microbial community, setting in motion metabolic changes that are associated with obesity and diabetes. Other zero-calorie sweeteners may cause the same problems, researchers say September 17 in Nature. Though the finding is preliminary, four of seven human volunteers eating a diet high in saccharin developed impaired glucose metabolism, a warning sign for type 2 diabetes.
“This is very interesting and scary if it really does hold for humans,” says Robert Margolskee of the Monell Chemical Senses Center in Philadelphia, who was not involved with the work. “There could be unintended consequences of these artificial sweeteners.”
Until recently, most sugar substitutes were thought to pass through the gut undigested, exerting little to no effect on intestinal cells. As ingredients in diet soda, sugar-free desserts and a panoply of other foods, the sweeteners are touted as a way for people with diabetes and weight problems to enjoy a varied diet. But the new study, led by computational biologist Eran Segal and immunologist Eran Elinav of the Weizmann Institute of Science in Rehovot, Israel, suggests that rather than helping people, the sweeteners may promote problems.After 11 weeks of drinking water doped with the sweeteners saccharin, sucralose or aspartame, mice had abnormally high glucose levels in their blood after eating. Digested food gets broken down into glucose, the most common carbohydrate, which then enters the bloodstream to be used as fuel or stored, often as fat. When glucose metabolism is impaired, high blood glucose levels — a hallmark of diabetes — can result. Via Artificial sweeteners may tip scales toward metabolic problems
A new simulation illustrates the explosiveness of the volcano that lurks beneath Yellowstone National Park in Wyoming. Around 640,000 years ago, the volcano blew its top and coated North America with roughly 1,000 cubic kilometers of ash, enough to fill Lake Erie twice over. A simulation of the eruption described August 27 in Geochemistry, Geophysics, Geosystems reveals that a similar outburst today would bury Billings, Mont., in more than a meter (about 40 inches) of volcanic glass shards and pulverized rock. Even New York and Atlanta would receive dustings several millimeters thick as winds whisked ash through the darkened atmosphere for days.
Researchers used simulation software called Ash3d that forecasts ash fall by applying global wind patterns to data from historical eruptions. Ash3d churns out results several times faster than previous simulators and is the first program to incorporate the physics of how ash particles clump within a cloud. While geologists say Yellowstone will likely never erupt again, scientists around the world use Ash3d daily to predict the potential fallout from restless volcanoes — including Bárðarbunga, the Icelandic volcano that began erupting in late August. Via Supervolcano blast would blanket U.S. in ash
In his new book, Scottish History For Dummies, Dr William Knox from the University of St Andrews explores the story of Scotland and its place within the historical narratives of Britain, Europe and the rest of the world. The book charts Scotland’s turbulent past to the present day, and explains the impact of key historical figures such as William Wallace, Robert the Bruce and philosopher David Hume. Here, writing for History Extra, Dr Knox reveals 10 things you (probably) didn’t know about Scottish history.
1) There is no genetically pure or original Scot – There is no common ancestral or genetic heritage that links the peoples of Scotland. The country was a patchwork quilt of various peoples grouped together in tribes who certainly never thought of themselves as Scottish. They owed allegiance only to their kith and kin, but in the campaigns against Roman imperialism they built federations that laid the basis of kingdoms.
Ancient Scotland was made up of four separate groups: Angles, Britons, Picts and Gaels (or Scoti), who each spoke a different language. Latin became the common language of the whole country only after the Christianisation of Scotland in the 6th century AD.
2) Kenneth McAlpin (810–858) was not, as is popularly claimed, the first king of Scotland – What McAlpin did was in 842 take advantage of the Picts who had been severely weakened militarily by punitive Viking raids, and unite the kingdom of the Gaels with that of Pictavia. But while he ruled over the whole of Scotland north of the river Forth, large parts of the country were still in the hands of the Vikings in the north and Islands, and in the south the Anglo-Saxons ruled. But McAlpin was referred to as king of the Picts – a title conferred on him at his coronation on Moot Hill at Scone, Perthshire, in 843 AD. It was not until the reign of Donald II (889–900) that the monarch became known as the ri Alban (king of Alba).
McAlpin’s achievement was to create a long-lasting dynasty that gradually extended the territorial borders of Scotland both north and south, but it was not until 1469 that what we know as Scotland today was established. See the next 8 facts here History Extra.
A NASA spacecraft that aims to study the upper atmosphere of Mars and reveal how its climate changed over time is poised to begin orbiting the Red Planet on Sunday. After a 10-month journey, the Mars Atmosphere and Volatile Evolution (MAVEN) probe is making its final approach to Mars and will begin circling Earth’s neighbor after 9:30 pm Sunday (0130 GMT Monday). MAVEN’s findings are expected to help pave the way for a future visit by humans to the Red Planet, perhaps as early as 2030. MAVEN, an unmanned spacecraft, has traveled 442 million miles (711 million kilometers) since it launched late last year.
NASA television coverage of the orbital insertion begins at 9:30 pm (0130 GMT). The process will start with the brief firing of six small thruster engines to steady the spacecraft, NASA said. “The engines will ignite and burn for 33 minutes to slow the craft, allowing it to be pulled into an elliptical orbit with a period of 35 hours,” the US space agency said. Once MAVEN begins circling Mars, it will enter a six-week phase for tests. Then, it begins a one-year mission of studying the gases in Mars’ upper atmosphere and how it interacts with the sun and solar wind.
Much of MAVEN’s year-long mission will be spent circling the planet 3,730 miles above the surface. However, it will execute five deep dips to a distance of just 78 miles above the Martian landscape to get readings of the atmosphere at various levels.
“The MAVEN science mission focuses on answering questions about what happened to the water and carbon dioxide present in the Mars system several billion years ago,” said Bruce Jakosky, MAVEN principal investigator from Colorado University-Boulder’s Laboratory for Atmospheric and Space Physics. “These are important questions for understanding the history of Mars, its climate and its potential to support at least microbial life.” Via MAVEN Mars spacecraft to begin orbit of Red Planet.
Thanks to Phil Krause for advising us of this interesting article
Scientists have greeted with skepticism (and in some cases derision) the claim that Jack the Ripper has been identified from DNA as an immigrant Polish barber named Aaron Kosminski. It was reassuring to see, for a change, that a good deal of the media coverage reflected that. Is it possible that defense attorneys on TV have taught people — including reporters — to look at claims for evidence more dispassionately?
Jack the Ripper, of course, is the near-mythical late-19th Century London serial killer, never firmly identified. He is believed to have brutally murdered and mutilated at least five women in 1888, perhaps as many as 11 all told. I say “he” because that seems most likely — the mutilation featured removing bits of a uterus and vagina — even though one of the many candidates endorsed by amateur detectives over the years was a woman. At the heart of the skepticism is provenance. When judging the worth of a piece of information, consider from whence it came. Continue reading
It’s the birthday of James Dewar, who was born in 1842 in Kincardine-on-Forth, Scotland. Dewar studied at the universities of Edinburgh and Cambridge. His research ranged over a wide range of topics in biology, chemistry and physics, but he is best known as a pioneer in low-temperature physics. He designed and built equipment that liquified and solidified gases, including hydrogen and oxygen, which had previously been considered permanently gaseous. Dewar also invented the vacuum flask – for use in determining the specific heat of palladium. He neglected to patent his invention, which was commercialized as a storage vessel for hot and cold drinks by two German glassblowers. They named the flask Thermos. Via Physicstoday
This beautiful photograph of the aurora borealis lighting up a glacial lagoon in Iceland has won James Woodend the top prize in the 2014 Astronomy Photographer of the Year competition. Via Facebook.
The Jökulsá á Fjöllum glacial river drains to the north of the Vatnajökull icecap in central Iceland, to the east of the Holuhraun rift zone eruption. Lava from this eruption has been migrating to the northeast as a stream and has finally reached the river.
Lava + water is a volatile mixture. When lava hits water, it flashes to steam and expands, causing small explosions and sending superheated debris into the air. The lava is continuing to migrate east and eventually may divert or dam the flow of this river, setting up the possibility for flash flooding (and potentially altering the Skínandi waterfall about 5 km past this location). Via Facebook.
Your brain doesn’t shut down when you go to sleep, in fact, a recent study has shown that it remains quietly active, and can process information to help you make decisions, just like when you’re awake.
A new study led by senior research scientist Sid Kouider and PhD student Thomas Andrillon at the Ecole Normale Supérieure de Paris in France has investigated how active our brains are when we’re asleep, and the results could have implications for the Holy Grail of humanity’s quest to become ever-smarter – learning in our sleep.
Previous studies have shown that rather than switching off from our environment when we sleep, our brains ‘keep one eye open’, so they can catch important information that’s relevent to us. This means we’re more likely to wake up when we hear someone say our names, or when our alarms go off in the morning, than to the less-pressing sounds of an ally cat scratching around the bins outside, cars driving past, or the periodic chime of a cuckoo clock.
Kouider and Andrillon wanted to take this finding a step further and found that complex stimuli from our environment can not only be processed by our brains when we sleep, but can actually be used to make decisions. It’s just like what’s going on in your brain when you’re driving your car home every day – you have to process so much information all at once and very quickly in order to safely operate your vehicle, but you’re so used to it, you barely even notice it happening. The same concept appears to apply to our decision-making processes when we’re asleep. Via Our brains can make decisions while we’re sleeping.
Diatoms are single-celled organisms found in oceans all over the world. There are estimated to be 100,000 species of these micron-sized creatures in existence, and they play a crucial role as one of the main food sources for marine organisms, including fish, molluscs and tunicates, such as sea squirts.
Once you get them under the microscope, the diatoms will reveal the incredible glass shells that contain their tiny bodies. During the Victorian era – the second half of the 19th century – scientists would pop them under their microscopes and lay them out in complex and beautiful arrangements, and UK-based biologist Klaus Kemp is one of the last remaining scientists on Earth to keep the practice alive.
Filmographer Matthew Killip made a documentary about Kemp, as the master of diatom art, and these stunning images were the result. More here Gallery: The otherworldly beauty of microscopic organisms.
The most spectacular artistic rivalry in British history will be revived this month when blockbuster exhibitions by two of the nation’s most renowned painters pitch them into direct competition, just as they were in their lifetimes two centuries ago. The simultaneous shows unavoidably provoke the question asked ever since the artists were showing side by side in the Romantic age: who is the greatest British painter ever?
Is it Joseph Mallord William Turner, whose glowing, occasionally abstract, visions of sea and sky and the violent elements are celebrated at Tate Britain from 10 September? Or is it his contemporary John Constable, whose acute observations of the clouds, trees and changing light of his native Suffolk are examined at the V&A 10 days later?
Pedigree – Constable was the son of a well-to-do middle-class mill owner and Suffolk corn merchant, while Turner was a self-made success, born above a Covent Garden barber’s shop. And while Constable was well-dressed and renowned for his good looks, Turner was famously ugly, labelled “uncouth” by his contemporaries.
Love life – Constable was a respectable married man, while the promiscuous Turner was a outspoken critic of wedlock. “I hate all married men,” he was once reported to have said, apparently a dig at Constable.
Rivalry – While Constable publicly praised his rival, in private he criticised his work as being “just steam and light”. It didn’t seem to do much to dent Turner’s confidence. “I am the great lion of the day,” he proclaimed.
Admirers – Ruskin said Turner while being a “hating humbug of all sorts” was “the painter and poet of the day”. But Lucian Freud insisted Constable was the greater painter. “You can admire Turner enormously, but never be moved by him really,” he said. “For me, Constable is so much more moving than Turner because you feel, for him, it’s truth-telling.” Edited from Turner and Constable exhibitions revive Britain’s greatest art rivalry
For future astronauts, the process of suiting up may go something like this: Instead of climbing into a conventional, bulky, gas-pressurized suit, an astronaut may don a lightweight, stretchy garment, lined with tiny, musclelike coils. She would then plug in to a spacecraft’s power supply, triggering the coils to contract and essentially shrink-wrap the garment around her body. The skintight, pressurized suit would not only support the astronaut, but would give her much more freedom to move during planetary exploration. To take the suit off, she would only have to apply modest force, returning the suit to its looser form.
Now MIT researchers are one step closer to engineering such an active, “second-skin” spacesuit: Dava Newman, a professor of aeronautics and astronautics and engineering systems at MIT, and her colleagues have engineered active compression garments that incorporate small, springlike coils that contract in response to heat. The coils are made from a shape-memory alloy (SMA)—a type of material that “remembers” an engineered shape and, when bent or deformed, can spring back to this shape when heated. Via Spacesuits of the future may resemble a streamlined second skin.