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Hayabusa-2: Japan’s rovers send pictures from asteroid

A picture of the asteroid taken by a robot rover and tweeted by a JAXA account.

Japan’s space agency (JAXA) has made history by successfully landing two robotic explorers on the surface of an asteroid.

The two small “rovers”, which were despatched from the Hayabusa-2 spacecraft on Friday, will move around the 1km-wide space rock known as Ryugu.

The asteroid’s low gravity means they can hop across it, capturing temperatures and images of the surface.

“Both rovers are in good condition,” the agency confirmed on Saturday. Source: BBC

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‘Gut sense’ is hardwired, not hormonal

If you’ve ever felt nauseous before an important presentation, or foggy after a big meal, then you know the power of the gut-brain connection.

Scientists now believe that a surprising array of conditions, from appetite disorders and obesity to arthritis and depression, may get their start in the gut. But it hasn’t been clear how messages in this so-called “second brain” spread from our stomachs to our cerebrum. For decades, researchers believed that hormones in the bloodstream were the indirect channel between the gut and the brain.

Recent research suggests the lines of communication behind that “gut feeling” is more direct and speedy than a diffusion of hormones. Using a rabies virus jacked up with green fluorescence, Duke researchers traced a signal as it traveled from the intestines to the brainstem of mice. They were shocked to see the signal cross a single synapse in under 100 milliseconds—that’s faster than the blink of an eye.

“Scientists talk about appetite in terms of minutes to hours. Here we are talking about seconds,” said Diego Bohórquez, Ph.D., senior author of the study and assistant professor of medicine at Duke University School of Medicine. “That has profound implications for our understanding of appetite. Many of the appetite suppressants that have been developed target slow-acting hormones, not fast-acting synapses. And that’s probably why most of them have failed.” The research appears Sept. 21 in the journal Science.

Your brain takes in information from all five senses—touch, sight, hearing, smell and taste—through electrical signals, which travel along long nerve fibers that lie beneath your skin and muscle like fiber optic cables. These signals move fast, which is why the scent of freshly baked cookies seems to hit you the moment you open a door.

Though the gut is just as important a sensory organ as your eyes and ears—after all, knowing when your stomach is in need of a fill-up is key to survival—scientists thought it delivered its messages by a multi-step, somewhat indirect process. Nutrients in your gut, the thinking went, stimulated the release of hormones, which entered the bloodstream minutes to hours after eating, eventually exerting their effects on the brain. Source: MedicalExpress

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NASA’s Dawn spacecraft will soon end its 11-year mission

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Hayabusa-2: Japan’s rovers ready for touchdown on asteroid

Minerva robotsJapan’s space agency is preparing to deploy two robotic explorers to the surface of an asteroid.

On Friday, the Hayabusa-2 spacecraft will despatch a pair of “rovers” to the 1km-wide space rock known as Ryugu.

Rover 1A and Rover 1B will move around by hopping in Ryugu’s low gravity; they will capture images of the surface and measure temperatures.

Hayabusa-2 reached the asteroid Ryugu in June this year after a three-and-a-half-year journey.

If all goes well, Hayabusa-2 will be the first spacecraft to successfully place robot rovers on the surface of an asteroid.

The 1km-wide space rock known formally as 162173 Ryugu belongs to a particularly primitive type of asteroid, and is therefore a relic left over from the early days of our Solar System. Studying it could shed light on the origin and evolution of our own planet.

The rovers are stored in drum-shaped container at the base of the Hayabusa-2 “mothership”. Collectively, they form a 3.3kg science package known as Minerva II-1. Source: BBC

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The Great Green Wall

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FEATURED ARTWORKS“L’EMBARQUEMENT POUR CYTHERE” – “THE PILGRIMAGE TO KYTHERA” BY JEAN-ANTOINE WATTEAU, 1717, CHARLOTTENBERG PALACE, BERLIN

Thank you to Alan Mason for this new post.

PART A- THE PAINTINGS IN CONTEXT

(i) Elitist Art

Readers of deskarati are offered here, a very different kind of artwork, from what is often presented. It comes from a period in art history which is no longer fashionable. This is elitist art. It is intended for aristocratic viewers with a classical education in the mythologies of the Gods and Goddesses of Classical Greece. Surprisingly, given the theme, the artist, Jean-Antoine Watteau, came from a humble French working-class background.

More importantly, the painting speaks of a love of, and yearning for the Greek Islands, of the Aegean Sea, which ran, as an undercurrent, in the culture of north-western Europe, for several centuries. It finally blossomed in the mid-twentieth century, with the development of regular colour cine-photography, colour television, and cheap air flights, to the Mediterranean countries, as exemplified by the holiday promotion picture. (2).


(ii) Spelling and Pronunciation

There is always a problem about transliterating Greek names into English, because there is no exact correspondence between the Greek alphabet, and the roman alphabet. (Here, “roman” with a small “r” is a typographical term, not an historical one.)

The Greek island of the painting, is spelled, “Κυθηρα”, and “Kythera” is accurate roman rendering, and is pronounced kee ther a. The French version is Cythère, and pronounced see tair. It is a pity that the Greek letter, kappa (Κ), a hard “k”, is so usually rendered as a soft “c” in both English and French, so that there is a tendency to call the island sith er a. I have chosen, without apology, to always use the spelling “Kythera” as it is closest to the actual Greek name.

(iii) The Goddess of Love

It is not immediately obvious, as to what is going on in the picture, and it requires some explanation. Like many of the most interesting paintings, opinions vary among experts as to the precise meaning of the work. The artist wisely offered no explanations to guide us. The Greek island of Kythera was thought to be the birthplace of Venus, the Goddess of Love, and was sacred to her worship. The various couples, who have paired off, in the painting, are going down to the beach, to “embark” or get aboard the vessel waiting in the bay. Hence, the painting may be interpreted as human beings in search of love.

(iv) Two Versions

Watteau painted two versions of this subject, and I have chosen the one which is in the Charlottenberg Palace, in Berlin, to head this essay, because the mast and sails of the ship are clearly shown on the left of the composition, and the quality of the graphics is better.

The other version is perhaps more famous, because it is in the Louvre Museum, in Paris, but the ship, though visible, is not so readily identifiable. Watteau gave both paintings the same title, in French, but English-speaking art historians call the Charlottenberg version, “The Pilgrimage to Cythera”, while the Louvre version is called, The Embarkation for Cythera”.


(v) “Fetes Champetres”

A popular conceit of the 1700s, among the wealthy and the aristocratic French, was the pursuit of a supposed country life. In reality, the life of most French peasants was hard and brutal, involving long hours of labouring in the fields, for men, women and children. They earned very little money for essentials, let alone luxuries, and were severely affected by regular crop failures and famines.

When the aristocracy came to play at being shepherds, or milkmaids, they were accompanied by retinues of servants, and carried all the luxuries of their wealthy lifestyle.


The name for these popular games (4) were “Fetes Champetres” (country feasts), or “Fetes Galants” (feasts of gallantry). The inspiration for these events, came not from their own poor French peasantry, but was provided by Classical authors, like the Latin poet, Virgil (70-19 BC) or the Greek writer Longus, (2 century AD). Virgil wrote a series of poems known as “The Eclogues” or “Pastoral Poems”, and an English prose translation of the first verse of the first poem is given below.

“THE DISPOSSESSED”

“Tityrus, while you lie there, at ease under the awning of a spreading beech, and practise country songs on a light shepherd’s pipe, I have to bid goodbye to the home fields and the ploughlands that I love. Exile for me, Tityrus — and you lie sprawling in the shade, teaching the woods to echo back the charms of Amaryllis (the girl friend of Tityrus).” (Ref B)

This is an impression of pastoral Greek country life, in Classical times, by a member the educated and leisured classes. Perhaps the poor country people of those days would tell us a different story. The life of the Greek peasant woman on her donkey (5) is probably much the same today as it would have been in Virgil’s time. Many of us who have visited Greek-speaking regions have seen elderly women in black, “widow’s weeds” toiling in the fields.


(vi) A French Regency (Régence)

These social activities or “Fetes Champetres” began after the death of King Louis XIV, in 1715. The king (6) had been an absolutist monarch, concentrating all the power of the French state in his person, and involving France in a series of costly foreign wars, paid for by heavy taxation. “When Louis XIV died, he was succeeded by Louis XV, his great grandson, who was only five years old. Because of the new king’s youth, a Regency was indispensible. The Regency was taken by Philippe II, Duke of Orléans, who was both nephew and son-in-law of Louis XIV. Orléans was a highly intelligent, undeniably charming, and very subtle man, but these assets were diminished by his well-deserved reputation for debauchery.” (Ref D)


The period, following Louis XIV, was “enjoyed by the aristocracy of France during the Régence, which is generally seen as a period of dissipation and pleasure, and peace, after the sombre last years of the previous reign. The work, by Watteau, The Embarkation for Kythera”, celebrates love, with many cupids flying around the couples, and pushing (8) them closer together.” (Reference A) These “cupids” are usually termed, “putti”, small naked boys, a regular feature in classical paintings. The two versions also feature statues of Venus, the Goddess of Love (9).

A more positive view of the Regent, Philippe II, Duke of Orléans, is given in Reference E. “Philippe disapproved of the hypocrisy of Louis XIV’s reign and opposed censorship, ordering the reprinting of books previously banned. During this time, he opened up diplomatic channels with Russia, which resulted in a state visit by Tsar Peter the Great. He acted in the plays of Molière and Racine, composed an opera, and was a gifted painter and engraver.”
Continue reading

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The Column of Marcus Aurelius

The Column of Marcus Aurelius and Faustina which stands in Piazza Colonna in Rome is thought to have been erected by Commodus in memory of his father and mother sometime around 180 CE. The column was inspired by its more famous predecessor Trajan’s Column which was set up, also in Rome, in 113 CE. The column carries representations carved in high relief of the emperor’s successful military campaigns against the Quadi across the Danube between 172 and 175 CE. Source Time team

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Book Binding

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Spinning Sphere of Molten Sodium


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Team develops ground-breaking flexible X-ray detector

Thanks to Jacki Thomas for suggesting this post. –

x-ray

Detectors that are presently used for mammograms and for dose measurements in radiotherapy are often rigid, causing errors in screening, or dose delivery to surrounding healthy tissue. This has raised concerns of additional tissue damage or the growth of secondary tumours. While flexible X-ray films such as those used in dentistry or chest x-rays bypass this issue, they are not able to achieve real-time imaging. Similarly, high-speed monitoring of people and vehicles over large geographical areas, which is important in border security, is impeded with the current technology.

In a study published in Nature Communications, researchers from the University of Surrey’s Advanced Technology Institute (ATI) detail how they have developed an X-ray detector by embedding oxide nanoparticles in a bulk organic structure that allows for large area detectors to be produced inexpensively. The detectors created by ATI researchers are able to achieve high sensitivity levels that strongly compete with current technologies, while still operating at low voltages, as well as over the whole X-ray energy range spectrum .

The team also proved that it is possible to create a device that conforms to the subject—something that is not possible with current X-ray detectors. This means that it could be possible for breast cancer screenings to be carried out by adapting the X-ray detector arrays to the specification of different patients. A new start-up company to further develop this technology and bring it to market—looking specifically at the health, food monitoring and pharmaceuticals sectors—has been formed.

Hashini Thirimanne, lead author of the study and Ph.D. student at the University of Surrey, said: “Our new technology has the potential to transform many industries that rely on X-ray detectors. We believe that this innovation could help save lives, and keep our borders more secure, and make sure that the food we eat is as safe as it could possibily be.”

Read more at: phys.org

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‘Killer’ kidney cancers identified by studying their evolution



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Life and Death of a Neutron

Experiments that measure the lifetime of neutrons reveal a perplexing and unresolved discrepancy. While this lifetime has been measured to a precision within 1 percent using different techniques, apparent conflicts in the measurements offer the exciting possibility of learning about as-yet undiscovered physics.

Now, a team led by scientists in the Nuclear Science Division at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has enlisted powerful supercomputers to calculate a quantity known as the “nucleon axial coupling,” or gA – which is central to our understanding of a neutron’s lifetime – with an unprecedented precision. Their method offers a clear path to further improvements that may help to resolve the experimental discrepancy.

To achieve their results, the researchers created a microscopic slice of a simulated universe to provide a window into the subatomic world. Their study was published online May 30 in the journal Nature.

The nucleon axial coupling is more exactly defined as the strength at which one component (known as the axial component) of the “weak current” of the Standard Model of particle physics couples to the neutron. The weak current is given by one of the four known fundamental forces of the universe and is responsible for radioactive beta decay – the process by which a neutron decays to a proton, an electron, and a neutrino.

In addition to measurements of the neutron lifetime, precise measurements of neutron beta decay are also used to probe new physics beyond the Standard Model. Nuclear physicists seek to resolve the lifetime discrepancy and augment with experimental results by determining gA more precisely.

The researchers turned to quantum chromodynamics (QCD), a cornerstone of the Standard Model that describes how quarks and gluons interact with each other. Quarks and gluons are the fundamental building blocks for larger particles, such as neutrons and protons. The dynamics of these interactions determine the mass of the neutron and proton, and also the value of gA.

But sorting through QCD’s inherent complexity to produce these quantities requires the aid of massive supercomputers. In the latest study, researchers applied a numeric simulation known as lattice QCD, which represents QCD on a finite grid.

While a type of mirror-flip symmetry in particle interactions called parity (like swapping your right and left hands) is respected by the interactions of QCD, and the axial component of the weak current flips parity – parity is not respected by nature (analogously, most of us are right-handed). And because nature breaks this symmetry, the value of gA can only be determined through experimental measurements or theoretical predictions with lattice QCD.

The team’s new theoretical determination of gA is based on a simulation of a tiny piece of the universe – the size of a few neutrons in each direction. They simulated a neutron transitioning to a proton inside this tiny section of the universe, in order to predict what happens in nature.

The model universe contains one neutron amid a sea of quark-antiquark pairs that are bustling under the surface of the apparent emptiness of free space.

“Calculating gA was supposed to be one of the simple benchmark calculations that could be used to demonstrate that lattice QCD can be utilized for basic nuclear physics research, and for precision tests that look for new physics in nuclear physics backgrounds,” said André Walker-Loud, a staff scientist in Berkeley Lab’s Nuclear Science Division who led the new study. “It turned out to be an exceptionally difficult quantity to determine.”

This is because lattice QCD calculations are complicated by exceptionally noisy statistical results that had thwarted major progress in reducing uncertainties in previous gA calculations. Some researchers had previously estimated that it would require the next generation of the nation’s most advanced supercomputers to achieve a 2 percent precision for gA by around 2020. More Here: PhysLink

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Carl Sagan – Cosmos – Eratosthenes

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Electric car breakthrough – New technology could recharge vehicles in seconds

Leveraging on the innovation for a new generation of Li-ion cell design, the electric vehicle has a pack comprising of hundreds of EV flash battery cells that can store enough energy for up to 300 miles (480 km) range on a 5-minute charge. This translates to 60 miles of travel on a 1-minute charge.

StoreDot’s core technology incorporates chemically synthesized organic molecules of non-biological origin. These innovative molecules demonstrate uniquely tunable optical and electrochemical properties, which allow for enhanced performance of energy storage devices.

LiBs (Lithium-ion batteries) power today both portable devices and EVs. While exhibiting relatively slow charging and discharging capabilities, over time, the internal chemical reactions inside the battery reduce their ability to retain energy. Yet, StoreDot has succeeded in maximizing the charge transfer rate, and has enhanced it to heighten the superior characteristics of FlashBattery.

LiBs contain inorganic compounds in the battery’s cathode, typically comprising metal oxides or polyanions which are continuously recharged by the insertion of lithium ions. This process limits ionic conductivity, thereby reducing the power density and shortening the battery’s life expectancy. Moreover, the electrolyte used in LiBs is highly volatile and flammable, posing a severe safety risk to consumers, critical especially in electric cars.

Using a unique multifunction electrode (MFE), StoreDot’s FlashBattery combines two benefits of energy storage solutions, incorporating the high-power rapid-charging rate capability with the high-energy storage ability.

This optimized charging ability is achieved through an innovative electrode structure containing proprietary organic polymers with Metal Oxide compounds of the cathode that trigger the redox reactions. This solution enables ions to flow from a modified anode to a modified cathode at a speed that is much faster than existing technologies. Together with a proprietary separator and electrolyte, this new architecture delivers a high current and low internal resistance, with enhanced energy density and a prolonged battery life.

While some battery manufacturers were able to improve only one of the following properties – either increased capacity, fast-charging or extended battery-life – StoreDot’s novel technology has optimized these three parameters simultaneously. Source: Express

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Stealth Spheres

A trick used by viruses to make us sick – “stealth spheres” – has been discovered by scientists.

It had been thought viruses were all lone wolves, each on a solo campaign of infection.

Instead they can form “packs” of up to 40 viruses and surround themselves with a fatty sphere that makes them invisible to our body’s defences.

The team at the US National Institutes of Health say their findings rewrite the textbooks of infection.

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Too hot? In 1858 a heatwave turned London into a stinking sewer

Illustration skeleton rows boat up Thames

Suffering in the hot weather? Spare a thought then for the population of London back in 1858, a year of sky-high temperatures and the Great Stink.

That year, the London Standard reported temperatures of over 30C by the middle of June and the weather stayed hot for several weeks. There was no air conditioning, no refrigeration, it was really hard to keep food fresh and there was no proper sewerage system, according to Museum of London curator Beverley Cook.

Everything you didn’t want ended up in the River Thames, from the contents of people’s chamber pots and the new-fangled flush lavatories, to dead dogs, decomposing food and industrial waste, including animal parts from abattoirs and chemicals from leather tanning factories along the river.

The Thames embankment had not yet been built, accidental drownings and river suicides were common and bodies were rarely recovered from the water.

On top of this, everything was horse-drawn – so the streets were full of massive piles of manure, says Ms Cook. “Flies were swarming down on this and of course transmitting disease such as diarrhoea and typhoid.” It was a nauseating mix and the heat made it worse – standing close to the river was enough to make you retch.

It was dubbed the Great Stink and it was no joke. Source – BBC

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New Electric Surfboard

 

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The Peculiar Math That Could Underlie the Laws of Nature

In 2014, a graduate student at the University of Waterloo, Canada, named Cohl Furey rented a car and drove six hours south to Pennsylvania State University, eager to talk to a physics professor there named Murat Günaydin. Furey had figured out how to build on a finding of Günaydin’s from 40 years earlier—a largely forgotten result that supported a powerful suspicion about fundamental physics and its relationship to pure math.

Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

The suspicion, harbored by many physicists and mathematicians over the decades but rarely actively pursued, is that the peculiar panoply of forces and particles that comprise reality spring logically from the properties of eight-dimensional numbers called “octonions.”

As numbers go, the familiar real numbers—those found on the number line, like 1, π and -83.777—just get things started. Real numbers can be paired up in a particular way to form “complex numbers,” first studied in 16th-century Italy, that behave like coordinates on a 2-D plane. Adding, subtracting, multiplying and dividing is like translating and rotating positions around the plane. Complex numbers, suitably paired, form 4-D “quaternions,” discovered in 1843 by the Irish mathematician William Rowan Hamilton, who on the spot ecstatically chiseled the formula into Dublin’s Broome Bridge. John Graves, a lawyer friend of Hamilton’s, subsequently showed that pairs of quaternions make octonions: numbers that define coordinates in an abstract 8-D space.

John Graves, the Irish lawyer and mathematician who discovered the octonions in 1843. MacTutor History of Mathematics

There the game stops. Proof surfaced in 1898 that the reals, complex numbers, quaternions and octonions are the only kinds of numbers that can be added, subtracted, multiplied and divided. The first three of these “division algebras” would soon lay the mathematical foundation for 20th-century physics, with real numbers appearing ubiquitously, complex numbers providing the math of quantum mechanics, and quaternions underlying Albert Einstein’s special theory of relativity. This has led many researchers to wonder about the last and least-understood division algebra. Might the octonions hold secrets of the universe?

“Octonions are to physics what the Sirens were to Ulysses,” Pierre Ramond, a particle physicist and string theorist at the University of Florida, said in an email. Continue reading

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Miles of Water Found on Mars. Could It Support Life?

A team of scientists announced today that they found a large body of liquid water beneath the southern ice caps of Mars. The discovery is the result of a decade-long effort to find liquid water on Mars and one that may rewrite the odds of finding life on the Red Planet.

The body of water is about 12.5 miles across and sequestered beneath nearly a mile of ice at the south pole. Its waters are likely so salty that they remain liquid despite the frigid -90˚ F conditions at the bottom. The discovery was reported in the journal Science.

The Mars Express spacecraft discovered the body of water beneath the southern ice cap.

If confirmed, this would be the most significant body of liquid water found on Mars to date. The only other evidence of liquid water on Mars has been of ancient bodies of water and transient seasonal flows. Finding a current stable of body of water, similar to the subglacial lakes found under Antartica, sparks hope that we may be closer than ever to discovering life on our planetary cousin.

“This lake on Mars, even if salty, is now the best site for finding extant life on Mars,” said Chris McKay, a senior scientist at NASA.

John Priscu, a microbiologist at Montana State University, says that liquid water may be the missing ingredient for life on Mars. “We can show that there’s enough energy to drive chemotrophic life—life that doesn’t need sun, but lives on chemistry,” he said. “There’s enough energy, but the problem we ran into is we didn’t have a hydraulic system to keep it going.”

Not everyone is convinced, however. A NASA spacecraft with the same mission and similar technology hasn’t detected the body of water, suggesting that it may be transient and not the permanent source that life would need to survive.

“It’s exciting and has super interesting implications if it’s validated,” says Jack Holt, a professor at the University of Arizona’s Lunar and Planetary Laboratory and an expert in the radar technology used to detect the liquid water. But, he cautions, “I’d say it’s not quite the smoking gun.” Source: PBS

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Royal Palaces at Nineveh

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The mighty Assyrian empire began as the small city-state of Ashur in what is now the north-eastern region of Iraq. It first asserted control over a large area in the 14th century BC, with peaks and troughs in power until it reached its greatest extent in the 7th century BC under the rule of the last great Assyrian king – Ashurbanipal. The empire spanned from the shores of the eastern Mediterranean to the mountains of western Iran and was ruled from large cities – this artist’s impression shows lavish royal palaces at Nineveh.

From libraries, letters and lion hunting to military campaigns and monuments, here’s everything you need to know about the Assyrians: http://ow.ly/gIZO30l2xLh

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