3-in-1 device offers alternative to Moore’s law

In the semiconductor industry, there is currently one main strategy for improving the speed and efficiency of devices: scale down the device dimensions in order to fit more transistors onto a computer chip, in accordance with Moore’s law. However, the number of transistors on a computer chip cannot exponentially increase forever, and this is motivating researchers to look for other ways to improve semiconductor technologies.

In a new study published in Nanotechnology, a team of researchers at SUNY-Polytechnic Institute in Albany, New York, has suggested that combining multiple functions in a single semiconductor device can improve device functionality and reduce fabrication complexity, thereby providing an alternative to scaling down the device’s dimensions as the only method to improve functionality.

To demonstrate, the researchers designed and fabricated a reconfigurable device that can morph into three fundamental semiconductor devices: a p-n diode (which functions as a rectifier, for converting alternating current to direct current), a MOSFET (for switching), and a bipolar junction transistor (or BJT, for current amplification).

“We are able to demonstrate the three most important semiconductor devices (p-n diode, MOSFET, and BJT) using a single reconfigurable device,” coauthor Ji Ung Lee at the SUNY-Polytechnic Institute told Phys.org. “While these devices can be fabricated individually in modern semiconductor fabrication facilities, often requiring complex integration schemes if they are to be combined, we can form a single device that can perform the functions of all three devices.” Source: 3-in-1 device offers alternative to Moore’s law

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A Billion Degrees of Separation

Source – BBC

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The Phaistos Disk

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The oldest living thing on Earth

Mayflies live a day, humans live a century, if we’re lucky, but what is the oldest living organism on the planet? For scientists, accurately proving the age of any long-lived species is a hard task.

Under the boughs of a 300-year-old sweet chestnut tree in the Royal Botanic Gardens in Kew, Tony Kirkham, head of the arboretum, confirms that trees are capable of outliving animals. Proving this can involve some traditional detective work, as he explains: “First of all we can look at previous records, to find out if a tree was growing there at a set date. Then we look at paintings and artwork, to look to see if that tree was present. And old ordinance survey maps quite clearly show ancient trees, especially important ones.”

A well-known way of measuring the age of a tree is by counting the rings in its trunk: one ring per year of growth. It’s a process known as dendrochronology and only works for certain types of tree that have an annual growth spurt. The obvious problem is that counting rings normally involves cutting down the tree. Arboriculturalists get around this by using an increment borer, a drill that allows them to take out a core, and count the rings without fatally damaging the tree. It’s a delicate art, and, Tony says, back in the 1960s, one scientist’s drill broke off inside the bristlecone pine tree he was sampling. The kit is expensive, and to help him recover the lost instrument, a forester helpfully cut down the tree. Once felled, the tree could be easily aged, and was found to be 5000 years old.

“It was terrible but so much science came out of that opportunity, and since then, we’ve found trees that are as old, if not older,” admits Tony.

A team of researchers in the US keeps a list, called the Old List, of officially dated ancient trees. They’ve found a sacred fig tree in Sri Lanka that is at least 2,222 years old. There’s a Patagonian cypress tree in Chile which, at 3,627 years old, is as old as Stonehenge. A Great Basin bristlecone pine in California’s White Mountains named Methuselah comes in at 4,850 years old.

But the oldest tree on the list, an unnamed bristlecone pine from the same location, has a core suggesting it is 5,067 years old.This time-worn tree has lived through the rise and fall of the Roman Empire. It was already established when the Ancient Egyptians started building pyramids. Source: The oldest living thing on Earth – BBC News

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JANE AUSTEN’S ENGLAND (G)


This essay is number seven in a series of twelve, about places associated with Jane Austen, although it does not claim to be a comprehensive gazetteer.

G. RETURN TO HAMPSHIRE

Jane Austen was born in rural Hampshire, in the village of Steventon, and spent the first twenty-five years of her life there (Essay A). Following her father’s retirement from the position of Rector in 1800, the family moved from Steventon to Bath. Jane was a dutiful daughter and accepted the move despite her grave misgivings. The family, Jane, her widowed mother, and sister Cassandra, had a rather nomadic existence after her father’s death n 1805, as they travelled around England on extended visits to relations.


(i) Portsmouth and Southampton

The map (2) is based on the twentieth century geography, and shows the two biggest towns, Portsmouth and Southampton as large grey areas of modern residential, commercial and industrial development. In Jane Austen’s day, there was a much greater contrast between the two towns. Portsmouth, with its great naval dockyard, was a scene of bustle and continual activity, as food and drink; together with equipment and materials; were taken aboard the great warships from the ships’ chandlers and provision merchants of the town.


The scene is admirably captured in the cartoon (3), by Thomas Rowlandson, a painter, portraitist and caricaturist, (Ref B) who was a contemporary of Jane Austen. As she mocked Georgian social manners in novels, he mocked it in pictures. As one art form influences another, so Rowlandson’s cartoon inspired the English composer, William Walton, (1902-1983) to write, in 1925, a short musical sketch, entitled, “Portsmouth Point”. It was the music which I encountered first, and some time later I saw the print.

Apparently, in the ships’ logs (formal accounts of the voyages) Portsmouth Point was abbreviated to “Po’m. P.” and in speech became “Pompey”, the sailors’ nickname for the naval base, and then the town, from the eighteenth into the twentieth century. (Ref C)


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Margaret Hamilton

Margaret Heafield Hamilton (born August 17, 1936) is an American computer scientist, systems engineer, and business owner. She was Director of the Software Engineering Division of the MIT Instrumentation Laboratory, which developed on-board flight software for the Apollo space program. In 1986, she became the founder and CEO of Hamilton Technologies, Inc., in Cambridge, Massachusetts. The company was developed around the Universal Systems Language based on her paradigm of Development Before the Fact (DBTF) for systems and software design.

Hamilton has published over 130 papers, proceedings, and reports about the 60 projects and six major programs in which she has been involved.

On November 22, 2016, she was awarded the Presidential Medal of Freedom by U.S. President Barack Obama for her work leading the development of on-board flight software for NASA’s Apollo Moon missions.

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Scientists discover 300,000 year old Homo sapiens fossils

An international research team led by Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany) and Abdelouahed Ben-Ncer of the National Institute for Archaeology and Heritage (INSAP, Rabat, Morocco) uncovered fossil bones of Homo sapiens along with stone tools and animal bones at Jebel Irhoud, Morocco. The finds are dated to about 300 thousand years ago and represent the oldest securely dated fossil evidence of our own species. This date is 100 thousand years earlier than the previous oldest Homo sapiens fossils. The discoveries reported in two papers in the June 8th issue of the journal Nature by Hublin et al. and by Richter et al. reveal a complex evolutionary history of mankind that likely involved the entire African continent.

The Moroccan site of Jebel Irhoud has been well known since the 1960s for its human fossils and for its Middle Stone Age artefacts. However, the interpretation of the Irhoud hominins has long been complicated by persistent uncertainties surrounding their geological age. The new excavation project, which began in 2004, resulted in the discovery of new Homo sapiens fossils in situ, increasing their number from six to 22. These finds confirm the importance of Jebel Irhoud as the oldest and richest African Middle Stone Age hominin site documenting an early stage of our species. The fossil remains from Jebel Irhoud comprise skulls, teeth, and long bones of at least five individuals. To provide a precise chronology for these finds, researchers used the thermoluminescence dating method on heated flints found in the same deposits. These flints yielded an age of approximately 300 thousand years ago and, therefore, push back the origins of our species by one hundred thousand years. Source: physorg

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Historians Draw Closer to the Tomb of the Legendary King Arthur

The deceased King Arthur before being taken to the Isle of Avalon

For many decades, researchers have tried to confirm the existence of King Arthur of Camelot, the legendary ruler that was said to have led the defense of Britain against the Saxons in the 5th century AD, and to find his final resting place. After years of speculations, the British researcher and writer Graham Philips believes he is closer than ever before.

According to the legend, King Arthur, after the battle with his enemy Mordred, was transported to the Isle of Avalon. Now, new research suggests that location may lie in a field in Shropshire, England.

Graham Phillips has been researching the life of King Arthur for many years. According to the Daily Mail , Phillips believes he has discovered evidence confirming that the medieval ruler was buried outside the village of Baschurch in Shropshire. In his latest book The Lost Tomb of King Arthur , he suggests that the most probable location of the tomb is outside the village in the old fort, dubbed ”The Berth” or at the site of the former chapel.

Phillips is calling on English Heritage for permission to start archeological works at The Berth, and in the former chapel nearby the Baschurch village. Phillips has already located a pit containing a large piece of metal, which Phillips believes may be remnants of King Arthur’s shield.

Phillips told the Daily Mail :

”In the Oxford University Library there is a poem from the Dark Ages which refers to the kings from Wroxeter who were buried at the Churches of Bassa – and when you think about anywhere in Shropshire that sounds similar, you think of Baschurch. There is a place that matches the description just outside the village, an earthworks known as The Berth, which were two islands in a lake, though obviously the lake has now gone.”

According to Phillip’s previous book, King Arthur lived in the Roman fortress at Wroxeter, a small village in Shropshire. Historical texts state that Arthur was born at Tintagel Castle in Cornwall, and later became a famous character of many legends, related to for example his sword – the Excalibur. However, Phillips believes that a lot of the legends about Arthur are wrong, including his place of birth, which Phillips says was Shropshire, and not South West England.

Apart from the sites nearby the Baschurch, Phillips claims that King Arthur could also be buried in a country lane in Birch Grove village . In the 1930s, archeologists discovered part of a gravestone there with the inscription in Latin ”Here Lies…”.

At the same time as Phillips is searching for the grave of Arthur, archeologist Dr Richard Brunning, from South West Heritage, started excavations at Beckery Chapel , near Glastonbury in Somerset. The aim of the work is to accurately date an early Christian chapel. It is hoped that the investigations may shed new light on King Arthur, who is said to have visited this place, and according to the legend had a vision of Mary Magdalene and the baby Jesus there. It is the first time since 1968 that archeologists have investigated the site. Moreover, the place is also famous as a part of the stories related to the Irish saint Bridget, who visited the site in 488 AD. Previous works suggested that before the chapel, a Saxon mastery had been present on the site. The most recent works will allow the precise dating of the monastic cemetery. Source – Ancient Origins

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National Geographic Tesla Motors Documentary

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SolarCity and Tesla Tau Microgrid

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This New Study Might Actually Explain The Weirdness That Is Déjà Vu

In French, déjà vu literally translates to “already seen”, and describes the phenomenon of having the strong feeling that the experience you’re having right now has already been experienced by you in the past. It’s clearly not a glitch in the Matrix, but scientists have been struggling for centuries to explain what prompts a feeling of déjà vu – and why. But now a team of neuroscientists just might have an answer.

Led by Akira O’Connor from the University of St Andrews in the UK, the team figured out how to trigger a feeling of déjà vu in a lab setting – making something that’s spontaneous, fleeting, and unpredictable a little bit easier to nail down. They did this by slightly tweaking a neat trick used by neuroscientists to implant false memories in the minds of their participants.

As Jessica Hamzelou explains for New Scientist, this involves reciting a list of related words, such as bed, pillow, night, and dream, but deliberately leaving out the single, most obvious word that links them all – in this case, sleep.

The participants are later asked about all the words they were told, and more often than not, will swear they heard “sleep”, along with the others.  So that’s how you implant a false memory, but it’s not quite the same thing as déjà vu. So O’Connor and his team added a step.  In the first part of the experiment, where the participants were hearing the related words, the researchers asked them if they’d heard a word starting with “S”. Of course, they hadn’t, so the participants replied “No.” Later, when the participants were asked to recall all the words they’d heard, they knew from earlier that they hadn’t heard a word starting with “S”, but at the same time, the false memory of sleep had been implanted, so it somehow felt familiar. “They report having this strange experience of déjà vu,” O’Connor told Hamzelou.

Trying this technique out on 21 participants, the researchers observed what was happening in their brains as they experienced the feeling of déjà vu. Interestingly, even though the technique involved a memory exercise and the participants were given a false memory, the parts of the brain related to memory weren’t the ones that lit up in the fMRI scans.

At the International Conference on Memory in Budapest, Hungary, last month, O’Connor told his peers that during the experience of déjà vu, frontal areas of the brain associated with decision-making were activated.

So what does decision-making have to do with the feeling that you’ve experienced something before? O’Connor told New Scientist that he suspects the feeling is caused by the brain sifting through its memory bank, and signalling that there’s some kind of error – I feel like I’ve experienced this before, but have no memory of it.

Just like sitting in a car makes our brains freak out because part of us thinks we’re moving and part of us thinks we’re staying still – a conflict that can often result in a very physical (and sometimes messy) response – the conflict in thinking you have a specific memory but don’t results in a very distinct feeling.

“It suggests there may be some conflict resolution going on in the brain during déjà vu,” Stefan Köhler from the University of Western Ontario in Canada, who wasn’t involved in the study, told New Scientist. Source: This new study might actually explain the weirdness that is déjà vu

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JANE AUSTEN’S ENGLAND (F)


This is essay is number six, in a series of twelve, about places associated with Jane Austen, although it does not claim to be a definitive gazeteer.

F. THE WARWICKSHIRE AVON AND THE COTSWOLDS

Given that Jane Austen (1775 – 1817) lived in the pre-railway age, she managed to visit quite a large number of places in England, travelling by horse-drawn coaches and carriages. However, the farthest north that she managed to reach was the village of Hamstall Ridware in Staffordshire (2).


Maggie Lane, (Ref B) in describing Blaise Castle, (Essay E) and discussing Catherine Morland, the naïve heroine of Northanger
Abbey, speculates on the possible whereabouts of this imaginary Abbey. “From the distances and directions given, Northanger must lie within the triangle bounded by Tetbury Cirencester Stroud,” (Ref B). This triangle is shown on the map of the Cotswolds (2).

I seem to recall that Henry Tilney, son of the Northanger Abbey family, said that it was near Swindon, which is something one would rather keep quiet about, nowadays. In Jane Austen’s day Swindon was just a sleepy market town. By the middle of the nineteenth century, Swindon had become an industrial town with a railway works, manufacturing locomotives for the Great Western Railway Company.

(ii) Adlestrop

“From Clifton, in July 1806, Jane Austen, her mother and sister proceeded to Adlestrop, where they stayed not at Adlestrop Park (3), but at the Rectory. This was unlikely to have been Jane’s first visit. Adlestrop Park was, so to speak, Mrs Austen’s ancestral home. It had belonged to her branch of the Leigh family since the Reformation; her father had been born there, and during her lifetime it had passed successively to her uncle, her cousin, and her cousin’s son.” (Ref B)


“Jane Austen rarely praised the older generation of her relations; with affection, so the summer visit of 1806 must have been very agreeable. In terms of their surroundings, there, was everything to make it so. The Cotswold countryside has a claim to be among the loveliest in England, its golden stone buildings most in harmony with nature. From the Rectory there is a superb view of the rolling landscape of Gloucestershire and Oxfordshire.” (Ref B)

The name, “Adlestrop” is better-known to most English readers through the poem, written in the summer of 1914, by Edward Thomas. When I visited Adlestrop, in the 1990s, it was because of the poem, which I find intensely moving, rather than for the association with Jane Austen, of which I was unaware at the time.

The poem is of four stanzas, but only the first one is quoted here. (Ref C)

“Yes, I remember Adlestrop–

The name, because one afternoon

Of heat the express train drew up there

Unwontedly. It was late June”

The poem speaks of days that are now over; the railway line is still there, but the station has gone, closed in 1966 as a result of the “Beeching Axe” on supposedly uneconomic branch lines and stations. Today the old railway station’s sign is mounted on the bench at the village bus stop (4).


Although the old Rectory of Adlestrop, at which Jane Austen and her family stayed, (5) is still in existence, as Adlestrop House, it seems that the much grander Adlestrop Park has not survived. I could find no reference to it, and the detailed satellite images show no large building in the village, despite the church and rectory showing clearly at the end of Main Street.


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When a star meets a black hole

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Survival of the fittest

Herbert Spencer coined the phrase “survival of the fittest”.

“Survival of the fittest” is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. The biological concept of fitness is defined as reproductive success. In Darwinian terms, the phrase is best understood as “Survival of the form that will leave the most copies of itself in successive generations.”

Herbert Spencer first used the phrase, after reading Charles Darwin’s On the Origin of Species, in his Principles of Biology (1864), in which he drew parallels between his own economic theories and Darwin’s biological ones: “This survival of the fittest, which I have here sought to express in mechanical terms, is that which Mr. Darwin has called ‘natural selection’, or the preservation of favoured races in the struggle for life.”

Darwin responded positively to Alfred Russel Wallace’s suggestion of using Spencer’s new phrase “survival of the fittest” as an alternative to “natural selection”, and adopted the phrase in The Variation of Animals and Plants under Domestication published in 1868. In On the Origin of Species, he introduced the phrase in the fifth edition published in 1869, intending it to mean “better designed for an immediate, local environment”. Via Wiki

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The Top Five Misconceptions About Evolution

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Here’s the difference between a Sports car, a Supercar, and a Formula 1 car

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Photographer Converted a Box Trailer Into a Giant Mobile Camera obscura

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Armed with the skills of a carpenter and obsessed with all things visual, Austin photographer Ian Kasnoff has created a mobile lab for his unique brand of artistic alchemy. His Trailer Camera was born in 2014, when Kasnoff decided to turn an 8-foot box trailer he owned into a camera obscura—a dark room with a small hole in one wall. Light passes through the opening and projects the outside world onto the walls and ceiling. After replacing the hole with a lens, Kasnoff began using light-sensitive photographic paper to capture large-format images. Now in its third incarnation—a 16-foot cargo trailer complete with built-in darkroom—the Trailer Camera has evolved into a sophisticated mobile device.

Source: Ian Kasnoff Converted a Box Trailer Into a Giant Mobile Camera

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JANE AUSTEN’S ENGLAND (E)


This is the fifth, in a series of twelve essays about some of the places in England associated with the life of Jane Austen. It is about a collection of places visited personally, with Jane Austen clearly in mind, but it is not a comprehensive gazeteer.

E. THE BRISTOL AVON

Jane Austen was quite familiar with the River Avon, from her time spent in Bath, where the river forms an attractive feature of the city. (Essay C) It is called the “Bristol Avon” to distinguish it from the “Warwickshire Avon”, and the “Wiltshire Avon” which are not far away, in adjoining counties. There are several other “Avons” in England, because the name is derived from the Welsh word, “afon”, pronounced “avvon” which simply means “river”.

As the map (2) shows, the Bristol Avon is a rather short river, rising in the southern Cotswold Hills, and flowing westwards to enter the sea at Avonmouth, on the Bristol Channel. At the end of the last Ice Age, around 12,000 years ago, the Bristol Avon, swollen by glacial meltwater, cut a 250 foot (76 m) deep channel, down into the softer rocks. This is the Avon Gorge.


The sudden decision, by Rev. George Austen, to retire from his position of Rector of Steventon, in Hampshire, and take his family to live in Bath, came as such a shock to his daughter, Jane, that she fainted away at the news. They left Steventon in December, 1800, and lived in Bath until the death of George Austen in January 1805. His widow and daughters were left in a precarious financial condition, and depended on allowances made to them by George’s far more affluent sons.

(i) Bristol and Clifton

Maggie Lane explains Jane Austen’s reactions to the situation in which she found herself,

“When Mrs Austen and her daughters left Bath for ever in July 1806, they had an entirely new home in view; but before settling down, they planned to spend the summer travelling and visiting relations. Their first stop was Clifton. For five years Jane had lived obediently but reluctantly in Bath, trying not to be discontented, but unable to write: the sense of release was immense, and Clifton came in for some of its afterglow.

Now part of the city of Bristol, Clifton (2) then lay just outside the ancient city boundary, a Gloucestershire village rapidly growing into a salubrious suburb and a fashionable resort to rival Bath. Why then should Jane have preferred it so decidedly?” (Ref B)


As explained, the Bristol Avon flows past Clifton in a deep gorge, and at the time of Jane’s visit, the river could only be crossed by boat (3), but by 1864 a suspension bridge (4) was completed to cross it. It was made to an 1831 design by the renowned engineer, Isambard Kingdom Brunel, who died before the work was completed. The span is 702 feet (214 m) between the piers, and it is 245 feet (75 m) above high tide. (Ref A).


Earlier, Maggie Lane poses the question as to why Jane Austen much preferred Clifton to Bath, and says, “Its attraction had a great deal to do with its airy clifftop situation, its elevation several hundred feet above the smelly, workaday centre of the city, and its proximity to the open green plateau of the Downs.” (Ref B) She points out the association of Clifton with health in her novels, from the juvenile production, “Lesley Castle”, to both “Persuasion” and “Emma”.
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FEATURED ARTWORKS “THE FIGHTING TEMERAIRE” BY J M W TURNER 1838 IN THE NATIONAL GALLERY, TRAFALGAR SQUARE, LONDON

This painting has been immensely popular with the ignorant, unlettered and uncultured members of the British public, as well as the rest, ever since it was first displayed in 1839. The artist, Turner would have altogether have approved of this. He called the painting, “my darling”, and only once, having loaned it for an exhibition, never did so again, and kept it safe in his own possession, until the day he died, when he bequeathed it to the nation in 1851. Turner gave it a longer title, few of us remember; “The Fighting Temeraire tugged to her last berth to be broken up, 1838”. Although the word “tugged” is still in use today, we would normally say “towed” about a vessel. The name, “Temeraire” is French and means, “Reckless or rash”.

A. THE PAINTING

(i) Popularity

In 2005 it was voted the nation’s favourite painting, in a poll organised by the BBC Radio 4 “Today” programme. Despite being reproduced on biscuit tins, chocolate boxes, postcards, and prints, the painting is treasured, because everyone knows these commercial mementoes are but a pale shade of the real thing. Many people might find it difficult to put into words the reasons why they find the painting so appealing. This is because it draws on deep and emotional popular feelings for the history and culture of Britain. Turner was in a long line of artists who had depicted the exploits of British seagoing men (2). The illustration below, (2) was one of many incidents in the Napoleonic wars. The “Nymph” is the nearer ship, and “La Cleopatra” is a French ship, now flying British colours after its capture.


“The Fighting Temeraire” painting speaks to us about the long and proud maritime history of the nation. It calls to mind, “England’s Darling”, Admiral Nelson, and the Battle of Trafalgar in 1805 against the maritime forces of the Napoleonic dictator. It recollects the sheer beauty of the square rigged sailing ship, as an example of the marine technology of the eighteenth and early nineteenth centuries. It also mourns the passing of an era, when beautiful sailing ships, dependent upon unreliable winds, were beginning to be replaced by dirty, noisy, ugly but more reliable steam vessels.

(ii) Turner’s Style

When Turner painted the picture, he was one of the nation’s best known artists having been an exhibitor at the Royal Academy for over forty years. Some have called him “the first Impressionist” in relation to the late nineteenth century artistic movement in France, because many of his paintings are distinctly “atmospheric”, or “impressionistic”. They sometimes create a ghostly or ethereal scene, from what might otherwise be a simple literal record of a rural landscape, or an historic building. One of the best examples of this is his painting of Norham Castle, in Northumberland, just one of many studies he made of it. (3)


“He spent much of his life near the River Thames and did many paintings of ships and waterside scenes, both in watercolour and in oils. Turner frequently made small sketches and then worked them into finished paintings in the studio. He almost certainly did not witness the actual towing of “Temeraire”, and used considerable licence in the painting which had a symbolic meaning for him, that his first audience immediately appreciated.” (Ref C, quoting Judy Egerton of the National Gallery, London,)
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Circle of Willis

The circle of Willis (circulus arteriosus cerebri) is an collection of arteries that are located at the base of the brain. The “circle” was named after Thomas Willis (1621-1675) by his student, Richard Lower. Willis authored Cerebri Anatome which described and depicted this vascular ring of arteries. The circle of Willis encircles the stalk of the pituitary gland and provides a connection between the internal carotid (the internal carotid is cut in this image) and the vertebrobasilar arterial brain supply systems. The circle of Willis is formed when each internal carotid artery divides into the anterior cerebral artery and middle cerebral artery. The anterior cerebral arteries are then united by an anterior communicating artery. Posteriorly, the basilar artery branches into a left and right posterior cerebral artery, forming the posterior circulation. The circle of Willis is completed by the posterior communicating arteries which join the posterior and internal carotid arteries. This arrangement potentially allows blood supply to the brain when there is occlusion of one of the internal carotid arteries, or vertebral arteries. However, the collateral circulation provided by this circle is typically insufficient to fully compensate for such an occlusion.

Image courtesy of Drs. Suárez-Quian and Vilensky.
Suárez-Quian, C.a. and Vilensky, J.A. 2016 All-in-One Anatomy Exam Review. Image-Based Questions and Answers. Volume 6: The Head. Apple iBooks.

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