Thursday, February 28, 2013

Crick and Watson decipher the DNA

Detailed DNA structure
On February 28, 1953,  American molecular biologist James D. Watson and English biophysicist Francis Crick announced to friends that they succeeded to determine the chemical structure of DNA.

Already in the 19th century biochemists were able to isolate DNA and RNA from the cell nuclei mixed together. They later found out that DNA and RNA had to be distincted from each other. The nuclein was identified by Friedrich Miescher in 1869 and he later on isolated the pure DNA from a salmon's sperm. The term 'nucleic acid' was then coined by Richard Altmann and it was only found in the chromosomes. The Lithuanian-American biochemist Phoebus Levene at Rockefeller Institute made further achievements concerning the DNA's structure, showing that its components, the sugar and phosphate chain were linked in the order phosphate-sugar-base. Each of these was named nucleotide and the scientist assumed that the DNA molecule consisted of a string of nucleotide units, which were linked together through phosphate groups. In his understanding however, the chain was short and its bases repeated in a fixed order, the theory that the DNA was a polymer was later suggested by Torbjorn Caspersson and Einar Hammersten.

Further efforts on the DNA's structure were made in the 1950's, and three known groups worked on the topic. Rosalind Franklin and Maurice Wilkins of King's College London belonged to the first group, Francis Crick and James Watson from Cambridge formed the second group and Linus Pauling and his team at Caltech depicted the third. Crick and Watson were able to build physical models of metal rods and balls, incorporating the chemical structured of the nucleotides. In the late 1940's, Pauling and his team discovered many proteins included helical shapes and also Wilkins found out that in the DNA's structure, helix' were somehow involved. Watson and Crick then began answering questions like whether the bases pointed toward the helical axis or away or what the angles and coordinated of all atoms and bonds were.

Due to an inspiration by Erwin Chargaff, Watson and Crick used X-ray diffraction and added several data by Rosalind Franklin, which resulted in the accurate model of the DNA's molecular structure. The extraordinary discovery was announced on February 28, 1953 and the news spread quickly. A new milestone was set in molecular biology.

At yovisto you may enjoy the video lecture 'You say you want a revolution: DNA analysis methods' by Prof. Dr. Qiang Zhou from Berkeley University.



References and Further Reading:


Wednesday, February 27, 2013

James Chadwick and the Discovery of the Neutron

James Chadwick
(1891 – 1974)
On February 27, 1932, English physicist and Nobel Laureate Sir James Chadwick published an article in the scienticic journal 'Nature' about the discovery of the neutron, a previously unknown particle in the atomic nucleus.

James Chadwick was born and raised in Bollington, England and later studied at Manchester and Cambridge University. Just before the start of World War I, Chadwick moved to Berlin, studying at the city's Technical University under Ernest Rutherford and Hans Geiger. During the war, Chadwick was detained to the 'Ruhleben internment camp' near Berlin, where he was allowed to put up a little laboratory. In these years he worked on the ionization of phosphorus and on the reaction of chlorine and carbon monoxide.

Returned to Cambridge, James Chadwick discovered an until then missing piece in the atomic nucleus in 1932, which was later known as the neutron. The search for the particle began around 1920, when Ernest Rutherford published his ideas on its possible existence. In his understanding, the neutron was to be a neutral double consisting of an electron that orbited a proton. About a decade later, Viktor and Dmitri Ivaneko however proved that the nucleus could never consist of protons and electrons and in the following year, German scientists found out that in case of alpha particles being emitted from polonium and falling on beryllium, boron or lithium, radiation was produced, which they took for gamma rays. Iréne Joliot-Curie (daughter of Marie Curie) and Frédéric Joliot proved that the previously discovered radiation ejected protons of high energy, when falling on a hydrogen containing compound.

The next person known to have been experimenting on the gamma ray theory was James Chadwick himself. He performed many experiments, stating that the radiation his German colleagues talked about contained uncharged particles of about the mass of a proton. The particles were called neutrons and his theory spread quickly, earning a great reputation amongst other scientists all over the world.

Chadwick's discovery was critical in the sense of general physics and especially in concerns of nuclear fission. The Italian scientist Enrico Fermi was through Chadwick's achievements motivated to investigate various nuclear reactions which led to Otto Hahn and Fritz Strassman discovering the first nuclear fission...but this is already another story. Chadwick became aware of the possibility building a nuclear bomb and joined the 'Manhattan Project' .

James Chadwick passed away on July 24, 1974 in Cambridge.

At yovisto, you may enjoy a short video lecture by Tyler DeWitt on the 'Atomic Structure: Discovery of the Neutron'



References and Further Reading:
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Tuesday, February 26, 2013

Thomas Newcomen and the Steam Engine

Newcomen atmospheric engine
On February 26 (or maybe also 24), 1664, English inventor Thomas Newcomen was born, who created the first practical steam engine for pumping water, the Newcomen steam engine.

As we know from a previous article on James Watt and the Steam Age Revolution, Watt was the one improving Newcomen's engine in the 18th and 19th century. Since the knowledge about the power of working with steam had been around for a while it is to be assumed that Newcomen was not the first to come up with the idea, building a steam engine. And indeed previous engineers working on a similar engine were for instance the Italian physicist Giambattista della Porta around 1600 and, more importantly, the French physicist Denis Papin during the end of the 17th century and the English innovator Thomas Savery. Papin constructed a model arrangement of cylinder and piston in which steam was admitted beneath the piston to move it up. [1] Savery patented his idea for using vacuum to draw water in 1698. He created the so far most efficient engine, but the pipes ruptured often and the force available for applying and raising water to the vessels was very limited.

Coming to Thomas Newcomen himself, why was he so motivated to build a steam engine, pumping water out of mines? Newcomen was born in Dartmouth, Devon in the early 1660's. He established himself as a well known ironmonger and to his big customer base belonged several mine owners, who repeatedly complained about the water flooding mines and endangering or even killing their workers as they made their way deeper and deeper into the mountains. Back then, workers were occupied with constantly removing the water with buckets, horses and roped, which was just too slow and expensive.

The common engines at that time used the condensed steam to create a vacuum, Thomas Savery's engine however used the vacuum to pull the water up. When suggested that Newcomen was to build a system against the flooding of mines, he instantly began experimenting, which took almost a whole decade. Newcomen combined the advantages of previous engines, especially from Savery's and Papin's devices and added his own, creating an engine that developed five horespower. Newcomen's engine, the most efficient of that time, was going to commercialize his idea but had to take Savery into partnership, since he used some of his technology. Newcomen's engine spread widely, but he experienced only little profit and after Watt's improved machine was distributed, Newcomen's became increasingly rare through the years. However, Newcomen was the first to create a successful steam engine, pumping water out of the dangerous minds and setting important standards for future engineering during the industrial revolution.

At yovisto, you may enjoy a video lecture by John Merriman from Yale University talking about the Industrial Revolution as part of his series on the European Civilization of 1648-1945.



References and Further Reading:

Monday, February 25, 2013

Friedrich Spee and the Cautio Criminalis

Friedrich Spee (1591-1635)
On February 25, 1591, German Jesuit and poet Friedrich Spee was born, who is best known for his book Cautio Criminalis, in which he argued publicly against the trials for witchcraft and against torture in general. He was one of the noblest and most attractive figures of the awful era of the Thirty Years' War.

Friedrich Spee von Langenfeld was born to a noble family at Kaiserswerth near Dusseldorf on the Rhine in Germany. On finishing his early education at Cologne, he entered the Society of Jesus in 1610. After prolonged studies and activity as a teacher at Trier, Fulda, Würzburg (a centre of the witchcraft persecutions), Speyer, Worms, and Mainz, was ordained priest in 1622. Two years later he became professor of moral theology at the University of Paderborn. His original wish to become a missionary in India was never granted by the Society. By this time Germany had entered into the turbulent times of the Thirty Years' War, a series of conflicts lasting from 1618 to 1648 caused mainly by Protestant and Roman Catholic factions during the Reformation. Starting from 1626 he taught at Speyer, Wesel, Trier, and Cologne, and was preacher at Paderborn, Cologne, and Hildesheim. While working in Peine on the 20th April 1629, Spee was a target of an attempted assassination and was seriously wounded. He resumed his activity as professor and priest at Paderborn and later at Cologne, and in 1633 removed to Trier. During the storming of Trier by the imperial forces in the course of the Thirty Years' War in March, 1635, he distinguished himself in the care of the suffering, and died soon afterwards from the results of an infection contracted in a hospital.

During the early 17th century at the height of some of the worst atrocities being perpetrated against witches in Germany, Friedrich von Spee was one of the first people in that country to effectively speak out against the witchcraft delusion. Following two bad harvests in 1626 and 1628 the population of Germany sought to release their frustrations with increased persecutions against witches. In the following years 600 witches were condemned in nearby Bamberg and a further 900 witches burned alive in Würzburg, places where the Prince Bishops of both were particularly zealous about hunting down and burning witches. The publication of Cautio Criminalis (Precautions for Prosecutors), written in admirable Latin, in 1631 put Spee's relations with the Jesuit hierarchy under considerable strain, even jeopardizing for a time his membership of the Society.

The book is an arraignment of trial for witchcraft, based upon his own awful experiences probably made in Westphalia. It is thought that Spee acted for a long time as "witch confessor" in Würzburg, as he seems to have knowledge of what could be considered the private thoughts of the condemned. The work was printed in 1631 at Rinteln without Spee's name or permission, although he was doubtlessly widely known as its author.
Many people who incite the Inquisition so vehemently against sorcerers in their towns and villages are not at all aware and do not notice or foresee that once they have begun to clamor for torture, every person tortured must denounce several more. The trials will continue, so eventually the denunciations will inevitably reach them and their families, since, as I warned above, no end will be found until everyone has been burned. (Cautio Criminalis, question 15)
Goldenes Tugendbuch (Golden Book of Virtues), a book of devotion, and the Trutznachtigall, a collection more than fifty sacred songs, which take a prominent place among religious lyrics of the seventeenth century.

On August 7, 1635, he died of the plague while tending the sick at Trier. He was only 44 years of age.

At yovisto you can learn more about the dark age of the witch hunt in Europe in Prof. Teofilo Ruiz lecture 'The Terror of History: The Witch Hunt in Early Modern Europe'.

References and Further Reading:
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Sunday, February 24, 2013

Jacques de Vaucanson and his Miraculous Automata

Jacques de Vaucanson
(1709 - 1782)
On February 24, 1709, French inventor and artist Jacques Vaucanson was born, who is best known for the creation of impressive and innovative automata and machines such as the first completely automated loom.

Jacques de Vaucanson grew up in a poor family, his father was occupied as a glove maker and Jacques himself wanted to become a clockmaker. He was educated by Jesuits but even though his interest in religious studies grew he always preferred working on mechanical devices. A big influence to Vaucanson depicted the medical surgeon Le Cat, who taught him in anatomy, wherefore it became easier constructing devices that would mimic biological functions.

But Vaucanson was not the first, interested in building automata. Constructions of these kind are known to have exist in the ancient Greece, like the Antikthera mechanism, which was designed to work out astronomical positions. In the 8th century, some wind powered automata were built and polymath Al-Jazari constructed several devices automatically playing music or automatic hand washing devices still in use today (for flush toilets). In the Renaissance, many clockwork automata were designed and built and France depicted the most important area for mechanical toys. Jacques de Vaucanson opened his first workshop in Lyon at the age of 18 and was therefore at the right location to improve his skills and find sympathizers. His duty in Lyon was to build various machines for a nobleman, but unfortunately, his efforts were not appreciated by everyone. When a group of governmental officials came to the city, he built several androids that would serve dinner and perform other helping tasks through the evening, but after that night his machines were declared foolish and were to be destroyed.

Still, the talented Vaucanson did not give up and created what has until then become the most successful biomechanical automation, 'The Flute Player' in 1737. After his presentation of the device at the Académie des Sciences the year after, his machine was considered a toy but still a revolutionary of its kind. In the following years he created further devices like the 'Tambourine Player' or his most famous 'Digesting Duck'. It consisted of more than 400 moving parts in only one wing and could do almost everything that a real duck could do, move its wings, drink water, digest, and defecate. His invention experienced a great positive impact. Voltaire even said that "without...the duck of Vaucanson, you will have nothing to remind you of the glory of France."

In the early 1740's, Vaucanson began his duties for the French government and created the world's first automated loom in 1745. Vaucanson designed further machines to automate the textile industry and more machine tools helping production processes, wherefore he became a member of the Académie des Sciences.

At yovisto, you may enjoy a prophetic talk from 2003 by roboticist Rodney Brooks, who talks about how robots are working their way into our lives.



References and Further Reading:

Saturday, February 23, 2013

The Amazing Diary of Samuel Pepys, Esq.

Samuel Pepys (1633-1703),
Painting by John Hayls, 1666
On February 23, 1633, English naval administrator and Member of Parliament Samuel Pepys was born, who is now most famous for the diary he kept for a decade while still a relatively young man. The detailed private diary Pepys kept from 1660 until 1669 was first published in the 19th century, and is one of the most important primary sources for the English Restoration period.
Blessed be God, at the end of the last year I was in very good health, without any sense of my old pain, but upon taking of cold. (Jan 1, 1660)
In this harmless and relaxed manner, one of the most important primary sources of English history in the 17th century begins. Samuel Pepys was born on February 23rd 1633 in Salisbury Court off Fleet Street. His father, John, was a tailor, his mother Margaret Kite was sister of a Whitechapel butcher and Samuel was fifth in a line of eleven children. In 1642, Samuel was sent to Huntingdonshire to live with his uncle, because of his health and fears of the Plague, from which several of his brothers died. There, he attended Grammar school, followed by St Paul's School after his return to London. After graduating at Cambridge University, Pepys was employed as secretary to Edward Montagu, a distant relative who was a councillor of state during the Cromwellian protectorate and later served Charles II. In 1655, Pepys married 15-year-old Elizabeth Marchant de Saint-Michel, daughter of a Huguenot exile, and became a clerk of the Exchequer. In 1658, he underwent a dangerous operation for the removal of a bladder stone. This cannot have been an easy option, as the operation was known to be especially painful and hazardous. Every year on the anniversary of the operation, he celebrated his recovery. In 1660, Pepys was made Clerk of the King's Ships to the Navy Board.
Up; and put on my coloured silk suit very fine, and my new periwigg, bought a good while since, but durst not wear, because the plague was in Westminster when I bought it; and it is a wonder what will be the fashion after the plague is done, as to periwiggs, for nobody will dare to buy any haire, for fear of the infection, that it had been cut off of the heads of people dead of the plague. (Sep 3, 1665, The Great Plague)
Pepys began writing his diary on 1 January 1660 at age 27. The diary is written in the shorthand system established by Thomas Shelton, with names in longhand. It ranges from private remarks, including revelations of infidelity - to detailed observations of events in 17th century England - such as the Great Plague of 1665, the Great Fire of London, the arrival of the Dutch fleet and the coronation of King Charles II - including some of the key figures of the era of Restoration, such as Sir Christopher Wren and Sir Isaac Newton. Pepys stopped writing his diary in the spring of 1669 - at the age of 36, his eyesight had gotten worse, and he feared losing his sight altogether. But, he never actually went blind.
Some of our maids sitting up late last night to get things ready against our feast today, Jane called up about three in the morning, to tell us of a great fire they saw in the City. So I rose, and slipped on my night-gown and went to her window, and thought it to be on the back side of Mark Lane at the farthest; but, being unused to such fires as followed, I thought it far enough off, and so went to bed again, and to sleep. (Sep 2, 1666, The Great Fire of London)
The following 34 years brought Samuel Pepys more appointments and acclaim. He became a Member of Parliament and Secretary of the Admiralty in 1673, and took part in organizing the navy during the war with the Dutch in 1672-74. In 1679, Pepys was accused of giving naval secrets to the French in the Popish Plot, and he was imprisoned in the Tower for six weeks. Howewer, he was soon cleared of charges and was reinstated as Secretary to the Admiralty in 1684. He served as President of the Royal Society from 1684-86. Isaac Newton's Principia Mathematica was published during this period and its title-page bears Pepys' name. In 1689, Pepys retired from public service at the accession of King William III.

In 1701, when his health began to fail, he moved out of London into the town of Clapham, where he completed the collection of his private library of 3,000 books, which was an amazing number of books by the time. When Pepys died on May 26, 1703, his library, including his Diary, was bequeathed to his nephew John Jackson, and subsequently to Magdalen College under the condition that the contents would never be altered. A century passed, however, before the shorthand diary was transcribed by the Reverend John Smith. He laboured at this task for three years, from 1819 to 1822, unaware that a key to the shorthand system was also stored in Pepys's library a few shelves above the diary volumes. Smith's transcription was the basis for the first published edition of the diary, edited by Lord Braybrooke, released in two volumes in 1825.

At yovisto you can learn more about the era of Restoration in England, about which Samuel Pepys was written his diary, in the lecture of Prof. Wrightson from Yale University.

References and Further Reading:

Friday, February 22, 2013

The World according to Arthur Schopenhauer

Arthur Schopenhauer (1788-1860)
On February 22, 1788, famous and most influential German philosopher Arthur Schopenhauer was born. He is best known for his book, The World as Will and Representation, in which he claimed that our world is driven by a continually dissatisfied will, continually seeking satisfaction.

Arthur Schopenhauer was born in Danzig (now Gdansk) on the 22nd of February 1788, as son of the merchant Heinrich Floris Schopenhauer, and Johanna Troisner. At age 17, his father placed him in a business school in Hamburg. Being apprenticed to merchants in Danzig in 1804 and afterwards in Hamburg, the expectation of his father was that Arthur should take over the family's business. But Arthur Schopenhauer had different plans for his life. After his father's death, he enrolled in a gymnasium in Gotha. He was a very gifted student and made so much progress that in two years he was able to read Greek and Latin with fluency. In October 1809 he entered the University of Göttingen as a student of medicine He later received the degree of doctor of philosophy from the University of Jena in 1813 in absentia, and in the same year the press at Rudolstadt published his first book, Über die vierfache Wurzel des Satzes vom zureichenden Grunde (On the Fourfold Root of the Principle of Sufficient Reason). In 1818 as lecturer at the University of Berlin Schopenhauer had the opportunity to visit Johann Gottlieb Fichte's famous philosophy lectures for two years, which he attended with a spirit of opposition.

Leaving Berlin in 1831 in light of a cholera epidemic that was entering Germany from Russia, Schopenhauer moved south and in June of 1833, he settled permanently in Frankfurt am Main, where he remained for the next twenty-seven years. There he entered on the life for which he has become famous: almost in a parody of Kant (who never got out of Königsberg), he dressed in an old-fashioned way and his daily life was defined by a deliberate routine: Schopenhauer would awake, wash, read and study during the morning hours, play his flute, lunch at the Englisher Hof, near city center Frankfurt, rest afterwards, read, take an afternoon walk in the company of his much-loved poodle Atma, check the world events as reported in The London Times, sometimes attend concerts in the evenings, and frequently read inspirational texts such as the Upanishads before going to sleep.

Schopenhauer's system of philosophy was based on that of Kant's. He did not believe that people had individual wills but were rather simply part of a vast and single will that pervades the universe: that the feeling of separateness that each of has is but an illusion. So far this sounds much like Baruch Spinoza's point of view or the Naturalistic School of philosophy's view. The problem with Schopenhauer, and certainly unlike Spinoza, is that, in his view, "the cosmic will is wicked ... and the source of all endless suffering." Schopenhauer saw the worst in life and as a result he was dour and glum. Believing that he had no individual will, man was therefore at the complete mercy of all that which is about him. His theories on aesthetics and ethics, pointing to the negation of the will as liberation, his "pessimistic" world-view that regarded nonbeing more highly than being, and his conception of music as the highest of the arts all exercised a powerful influence on both Wagner and Nietzsche.

In the intervening years he had written several works including On the Will in Nature (1836), The Freedom of the Will (1841), and On the Basis of Morality (1841). Although an Essay on the Freedom of the Will had been recognized through the awardance of a cultural prize in Norway in 1839 he was into his sixties when the publication of his collection of essays Parerga and Paralipomena (i.e. Additions and Omissions, in 1851) really brought public attention to his life's work. Schopenhauer had a robust constitution, but in 1860 his health began to deteriorate. On 21st September 1860,  Schopenhauer rose in the morning and sat down alone to breakfast; shortly afterwards his doctor called and found him dead in his chair.

At yovisto you can learn more about Arthur Schopenhauer and his work in the discussion between Bryan Magee (The Philosophy of Schopenhauer) and historian of philosophy Frederick Copleston, S.J.

References and Further Reading:




Thursday, February 21, 2013

Edwin Land - Father of the Polaroid Instant Camera

SX-70 Polaroid Camera
On February 21, 1947, American scientist and inventor Edwin Land introduced the very first instant camera together with an associated film. Land's new camera would allow people to produce a black and white photograph in about sixty seconds. The new film already contained the necessary chemicals to develop and fix the image directly on the photographic paper.

Edwin Land studied chemistry at Harvard University but dopped out in his freshman year, leaving for New York City, where he invented the filters able to polarize light. Unfortunately, Land was not associated with an educational institution, wherefore he had to work with rather unprofessional equipment. Rumors now say that the inventor secretly sneaked into the labs of Columbia University to perform his tests there at night.

Finding out, that he could build a film with millions of tiny polarizing crystals in an accurate alignment instead of growing one large crystal of the polarizing substance, depicted a great milestone for Land and in 1932 the Land-Wheelwright Laboratories were established. Wheelwright, Land's instructor at Harvard University, and Land himself were going to commercialize their ideas. Only a few years later, investors from the Wall Street put a great amount of money in the company that soon was renamed to Polaroid Corporation.

Their inventions were first applied at sunglasses, televisions, and during World War II used for military purposes as well. However, the first Polaroid camera was demonstrated for the first time in 1947, back then called the Land camera leading to an instant success for the company and their workaholic founder Land. Still, the instant camera only depicted a side product of the company. For instance in the 1950's they took part in designing the optics of the spy plane 'Lockheed U-2'.

Another breakthrough to Land and his instant camera happened in the 1970's when he released the famous SX-70 camera and film, the first edition to automatically eject and develop photos without further chemicals that needed to be applied. His demonstration was unique, he preferred dramatic showcases with live music, and professional art directed stage settings. This all reminds us of Steve Jobs and his dramatic presentations of the newest Apple products and indeed, Land was a great inspiration to Jobs. Steve Jobs and Edwin Land had much in common, they both depicted icons of their era, ready to surprise folks with their new ideas and Polaroid's instant camera had probably the same influence and influenced people's social status as certain Apple products might do today.

But coming back to Land, a great scientist, inventor, a man of ideas and a man with ideals who not only made decisions in financially favors of the company, but also considered doing what he felt was right as a humanist. He was one of the leaders of the affirmative action movement, hiring and training women not only as secretaries, but as scientists engineers with responsibility. Unfortunately, the company's investors often doubted his decisions and after the financial disaster of the 'Polavision' camera he resigned as Chairman, founding a science institute himself.

Edwin Land passed away on March 1, 1991 in Cambridge Massachussetts.

At yovisto, you may enjoy a video by Dan Armendariz explaining exposure techniques in photography as part of his lecture series Exposing Digital Photography.



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Wednesday, February 20, 2013

Ansel Adams and the Beauty of Black and White Photography

The Tetons and the Snake River (1942) Grand Teton National Park, Wyoming
by Ansel Adams. Source: http://www.archives.gov/research/ansel-adams/
On February 20, 1902, American photographer and environmentalist Ansel Easton Adams was born. He is best known for his black-and-white landscape photographs of the American West, especially Yosemite National Park. Together with Fred Archer, Adams developed the Zone System as a way to determine proper exposure and adjust the contrast of the final print.

Ansel Adams was born into a wealthy family in San Francisco. Despite the fact that the Panic of 1907 hit the Adams family hard, his father Charles always supported, encouraged and influenced his only son Ansel. His shyness, possible dyslexia and from the earthquake in early years damaged nose caused him problems at school, which he began compensating in the nature and the music. His early intentions to becoming a professional pianists taught him discipline and opened up the world of arts to the young Adams.

In 1916, Adams began spending an essential amount of his time at the Yosemite Sierra, which determined a great part of his life. At the national park, he began taking first photographs and after his first visit, he spent nearly every summer there in his beloved nature. Joining the Sierra Club depicted an important step to Adams, since they published his first imaged in their Bulletin and organized his first one man exhibition. Another dramatic influence was Albert Bender, who successfully supported Adams in any thinkable way causing him several deals, exhibitions and new contacts to conquer the world of arts as a professional photographer, not as a pianist. First publications of Adams were technical articles and his in 1935 distributed book 'Making a Photograph'.

Adams was not only a special photographer in the artistic sense, he was known for his great knowledge of camera and photographic techniques, which many colleagues consulted him for. His knowledge was essential to the technical development of Polaroid, Hasselblad and other related companies. The complex 'zone system' he developed concerned the controlling and relating exposure and development. To photographers it was then possible to creatively visualize an image and produce a photograph that matched and expressed that visualization. [1] His ten volumes of manuals on technical issues of photography are up to date the most influential ever produced.

Adams depicts a representative of 'straight photography' (as part of the f/64 group of fellow photographers), following the tradition of realistic art, rejecting the pictorialism often favored in Adams' times. Even though Adams dedicated his life to photography, he transferred his principles of musical composing to visual arts seeing the camera as his instrument. Ansel Adams is known as the extraordinary photographer of the 20th century and his works are characterized by his love for technical perfection and his passion for untouched places of nature in the Yosemite Sierra and beyond. He is one of America's most appreciated artists of all times, who was able to strengthen the photography's role in the world of visual arts.

At yovisto you may enjoy a video lecture by Dan Armendariz giving an introduction to the course
'Exposing Digital Photography' in which he explains various camera types and photography techniques.



References and Further Reading


Tuesday, February 19, 2013

Nikolaus Copernicus and the Heliocentric Model

Nicolaus Copernicus
(1473 - 1543)
On February 19, 1473, Renaissance mathematician and astronomer Nikolaus Copernicus, who established the heliocentric model, which placed the Sun, rather than the Earth, at the center of the universe, was born. With the publication of his research he started the so-called Copernican Recolution, which started a paradigm shift away from the former Ptolemaic model of the heavens, which postulated the Earth at the center of the galaxy, towards the heliocentric model with the Sun at the center of our Solar System. In 1543 Nicolaus Copernicus published his treatise De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres), which presented a heliocentric model view of the universe. It took about 200 years for a heliocentric model to replace the Ptolemaic model. But, Copernicus was not the first to propose a Heliocentric model. Actually, even the ancient Greek philosophers argued about, as e.g. Aristarchus of Samos in the 3rd century BCE, who had developed some theories of Heraclides Ponticus (speaking of a revolution by Earth on its axis) to propose what was, so far as is known, the first serious model of a heliocentric solar system.

Nikolaus Copernicus was born in Poland as the son of successful merchants. He was well educated, speaking Latin, German, and Polish fluently, wherefore most of his later publications were published in Latin. In 1491, Copernicus began his studies at the University of Krakow gathering the basic knowledge in mathematics and astronomy. Besides his astronomical interests, Copernicus evolved a great interest in the philosophical ideas of Aristotele, works by Euclid, or Johannes Regiomontanus' Tabulae directionum, gathering a great private library. Even though the time at Krakow University was important to his future career in concerns of his knowledge and experience, he left the institution without a degree. Copernicus then attended Bologna University where he was highly influenced by Domenico Maria de Novara, who supported the young scientists with the opportunity to observe and measure the sky.

The work on the heliocentric theory began during Copernicus' time as his uncles' secretary in Heilsberg. The first outline was written around 1540 and contained a description of the theory without mathematical explanations and was not intended to be published at any time. Only few fellow astronomers were supposed to read and contribute to his ideas. Tycho Brahe however published a few fragments of the manuscript in his own work 'Astronomiae instauratae progymnasmata'. Further studies by Copernicus included the observation of the planets Mars and Saturn as well as several studies on the Sun. Especially during the observations of the Sun, Copernicus began measuring the movements of the planets in relation to the Sun. Around 1532, he completed the famous manuscript 'De revolutionibus orbium coelestium' and in the following year, Pope Clement VII was told about it and encountered Copernicus with high interest. Still he refused to publish his book despite the fact thet his theory already spread throughout Europe. It is assumed that he feared criticism by fellow scientists as well as problems with the Church. However, he eventually agreed to have the book published in 1543, but unfortunately he passed away in the same year.

One of the first to neglect Copernicus' heliocentric theory was the Catholic Church's chief censor. Others rejected the thought of mathematical physics, unable to foresee that Copernicus' theory would change the field of physics back then critically. His thoughts were claimed to be unproven and irrational since they caused various conflicts with the Bible, especially the Battle of Gibeon in the book of Joshua in which Joshuas prayers cause the Sun and Moon to stand still. One of his greatest opponents depicted Martin Luther, but Philip Melanchthon eventually saw the theory's importance and the need to teach those wherefore the University of Wittenberg became a center where the heliocentric system was to be studied. Tycho Brahe, one of the greatest astronomers before the invention of the telescope appreciated Copernicus' efforts, but rejected his system, wherefore he developed his own called the ‘geoheliostatic’ system in which the two inner planets revolved around the sun and that system along with the rest of the planets revolved around the Earth.

On the long run, Copernicus' system was widely accepted and caused the so called 'Copernican Revolution', a now often used metaphor supporting modern developments. 

At yovisto, you can learn more about the scientific, social and religious impact of the Copernican Revolution with the lecture 'Mathematics, Motion, and Truth: The Earth goes round the Sun' by Jeremy Gray of Gresham University.

(We are currently running some maintenance, the video will be available very soon! We will keep you posted :-) )



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Monday, February 18, 2013

Sophie Scholl and the White Rose

Sophie Scholl (1921-1943)
On February 18, 1943, Sophie Scholl and her brother Hans brought a suitcase full of leaflets to the University of Munich, calling for passive resistance against the Nazis, and were arrested. Four days later, Sophie Scholl, her brother Hans and their friend Christoph Probst were found guilty of treason and condemned to death.

Sophie Scholl was born on 9th May, 1921 as the daughter of Robert Scholl, the mayor of the small village Forchtenberg am Kocher. In 1929, however, the U.S. stock market crashed, causing a worldwide economic depression. In Forchtenberg, Robert Scholl was up for re-election, but he lost. Fortunately for the family, he managed to find a job in Stuttgart and later in Ulm, where the Scholl family moved to in 1933, when Sophie like most others of her age joined the Bund Deutscher Mädel (BDM, League of German Girls), a branch of the Hitler Youth. At first she was enthusiastic but, influenced by the views of her father, she became increasingly critical of Adolf Hitler and his Nazi government. Sophie's brother, Hans Scholl, was also growing disillusioned with Nazi Germany and in 1937 he even was arrested and briefly jailed after being accused of subversive activities. In spring 1940, Sophie graduated from secondary school and became a kindergarten teacher at the Frobel Institute in Ulm-Soflingen. Next, she attended a six months auxiliary war service as a nursery teacher in Blumberg and in May 1942, she entered the University of Munich as a student of biology and philosophy. Later that year her father was imprisoned for making critical comments about Adolf Hitler to one of his employees. He was found guilty of saying: "this Hitler is God's scourge on mankind, and if this war doesn't end soon the Russians will be sitting in Berlin."

Sophie's brother Hans, who was studying medicine at Munich, introduced her to his friends. Although this group of friends was eventually known for their political views, they were initially drawn together by a shared love of art, music, literature, philosophy and theology. Several members of the group had witnessed Nazi brutality first hand and thus they adopted the strategy of passive resistance and formed the "White Rose" Resistance movement. Until this time, the group had only heard about the cruelty the Jews were suffering, but over the next few months, Hans and his former classmates from university Alexander Schmorell, Willi Graf, and Jürgen Wittenstein saw first hand the horrific treatment they were subjected to. Together, they witnessed the brutal operation of the Schutz Staffeinel (SS) in the Warsaw Ghetto in Poland as well as the horrors taking place in the Soviet Union.

When Hans Scholl returned to Germany in October, 1943, he and the White Rose had more than enough information and they began publishing leaflets en masse, going into detail about the murderous mission of the SS. While the leaflets were first sent to addresses simply taken randomly from telephone directories, they wanted to concentrate their efforts on mailing to university lecturers and the owners of bars. Contrary to popular belief, Sophie Scholl was not a co-author of these articles. Her brother had been initially keen to keep her unaware of these activities, but once she discovered them, she joined him and proved very valuable to the group: as a woman, her chances of being randomly stopped by the SS were much smaller. On 18 February 1943, Sophie Scholl and the rest of the White Rose were arrested for distributing the sixth leaflet at the University of Munich. In the People's Court before Judge Roland Freisler on 22 February 1943, Sophie Scholl was recorded as saying these words: Somebody, after all, had to make a start. What we wrote and said is also believed by many others. They just don't dare express themselves as we did.

Today, the square where the central hall of Munich University is located has been named Geschwister-Scholl-Platz after Hans and Sophie Scholl. Many schools, streets and places all over Germany are named in memory of the members of the White Rose. They are considered heroes by the people of Germany, and many young people today look to their example for inspiration.

At yovisto you can learn more about Sophie Scholl and the White Rose in the inaugural lecture of Prof. Frank McDonough from Liverpool John Moore's University: 'Sophie Scholl - A Woman for all seasons'.

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Sunday, February 17, 2013

Giordano Bruno and the Wonders of the Universe

Giordano Bruno at the Campo di Fiori in Rome
photo: ©Lysander07
On February 17, 1600, Domonican friar, philosopher, mathematician and astronomer Giordano Bruno was burned on the stake after the Roman Inquisition found him guilty of heresy. His cosmological theories went beyond the Copernican model in proposing that the Sun was essentially a star, and moreover, that the universe contained an infinite number of inhabited worlds populated by other intelligent beings.

Giordano Bruno was born as Filippo Bruno in Nola,  in the Kingdom of Naples, in 1548 as the son of Giovanni Bruno, a soldier, and Fraulissa Savolino. In his youth he was sent to Naples for education, where he was tutored privately at an Augustinian monastery and attended public lectures at the Studium Generale. At the age of 17, he entered the Dominican Order at the monastery of San Domenico Maggiore in Naples, taking the name Giordano. In 1572 he finished his novitiate and became ordained priest.

Giordano's exceptional expertise in the art of memory brought him to the attention of patrons, and he was brought to Rome to demonstrate his abilities to the Pope. His memory enhancement techniques, described in his book "The Art of Memory" are still used today. Though outspoken, and perhaps, not truly appreciated while in the Dominican Order, Giordano's troubles truly began around 1584 with the publication of his book "Dell Infinito, universo e mondi" ("Of Infinity, the Universe, and the World"). Being a philosopher and not an astronomer, Giordano Bruno would not have even warranted our attention if not for this book and the consequences of it. Hearing the ideas of Nikolaus Copernicus about the nature of the universe sent Giordano Bruno into a veritable frenzy of philosophical thought. If the Earth was not the center of the universe, and all those stars clearly seen in the night sky were also suns, then there must exist an infinite number of earths in the universe, inhabited with other beings like ourselves.

Of course Bruno was aware that this contradicted the Biblical version of the universe, but he put forward the same argument as Galileo Galilei would some years later, namely that the Bible should be seen as providing moral teaching, not the teaching of physics. In his writings Bruno also argues that Christianity is a religion which is held through faith, not through philosophical or scientific reasoning. Moreover, Bruno's teachings that different Christian Churches should be allowed to coexist and that they should respect each others views does not look to our eyes a major crime but it did not go down well in the religious climate which then prevailed. Bruno was invited to return to Italy and, thinking that the Catholic Church was now more tolerant following the death of the strict Pope Sixtus V, he accepted. Many believe that the invitation was a trick to bring him before the Inquisition, and Bruno fell for it.

Returning to Italy, Bruno went first to Padua, where he taught briefly, and applied unsuccessfully for the chair of mathematics, that was assigned instead to Galileo Galilei one year later. Accepting an invitation to Venice from the patrician Giovanni Mocenigo, Bruno moved to Venice in March 1592. For about two months he functioned as an in-house tutor to Mocenigo. When Bruno announced his plan to leave Venice to his host, the latter, who was unhappy with the teachings he had received and had apparently developed a personal rancour towards Bruno, denounced him to the Venetian Inquisition, that had Bruno arrested on May 22, 1592. Among the numerous charges of blasphemy and heresy brought against him in Venice, based on Mocenigo's denunciation, was his belief in the plurality of worlds, as well as accusations of personal misconduct. Bruno defended himself skillfully, stressing the philosophical character of some of his positions, denying others and admitting that he had had doubts on some matters of dogma.

The Roman Inquisition, however, asked for his transferal to Rome, where he was imprisoned for seven years during his lengthy trial, lastly in the Tower of Nona. Some important documents about the trial are lost, but others have been preserved, among them a summary of the proceedings that was rediscovered in 1940. The Pope expressed himself in favor of a guilty verdict. Consequently, Bruno was declared a heretic, handed over to secular authorities on February 8, 1600. At his trial he listened to the verdict on his knees, then stood up and said: "Perhaps you, my judges, pronounce this sentence against me with greater fear than I receive it." A month or so later he was brought to the Campo de' Fiori, a central Roman market square, his tongue in a gag, tied to a pole naked and burned at the stake, on February 17, 1600.

In history, science and christian religion had a difficult relationship. Unfortunately, the church was in position to claim the unquestionable truth, and everybody who tried to challenge the church, was in danger to be declared a heretic. But, also science was not always flawless. Learn more about 'Science's First Mistake' in the lecture of Prof. Ian Angell from Gresham College.


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Saturday, February 16, 2013

Sir Francis Galton - Polymath

Sir Francis Galton
(1822 - 1911)
On February 16, 1822, the cousin of Charles Darwin, Sir Francis Galton was born. Galton the polymath, was known for his fundamental contributions to anthropology, geographics, genetics, psychology, statistics, and eugenics.

Born in the near of Birmingham, the cousin of Charles Darwin grew up in a family of educated relatives and friends, since the family had close contact to the Royal Society. The child prodigy received a decent school education followed by the studies of medicine at London and mathematical studies at Cambridge. Next to his studies, Galton loved traveling and became a member of the Royal Geographical Society, where he was awarded several times for his writings on 'South West Africa'.

To the numerous studies in the various fields he has been active in belonged the masterpiece of Darwin, 'The Origin of Species'. He began researching on variations of species and the human population leading in fundamental results concerning psychological and physical traits of mankind. Through these studies he was able to lay the foundations of differential psychology and the design of psychological testing. Even though Galton admired his cousin's work on natural selection, he challenged some of his ideas, like the theory of pangenesis. Through transfusions of blood between similar breeds of rabbits, he was to disprove Darwin's ideas unsuccessfully.

His approaches in biology would later lead Galton to developing completely new statistical methods and ways to work with data. These laid the foundations for most operations in social sciences up to this day. He designed the method of standard derivation, discovered bivariate normal distribution and studied regression analysis.

But not only that Galton was a man highly appreciated in numerous scientific fields, he also began writing the novel 'Kantsaywhere' in 1910. He later gave the material to his niece, who unfortunately burned most of it since she was offended by certain love scenes in the book and it was never published.

For his achievements, Galton was knighted in his later years and honored after his passing with literary works, monuments and even the flowering plan genus Galtonia was named after him.

At yovisto, you may enjoy a video lecture on statistics by Hank Ibser at Berkeley.



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Friday, February 15, 2013

Nikolaus Wirth and PASCAL

Niklaus Wirth giving a lecture
On February 15, 1934, Swiss computer scientist Niklaus Emil Wirth was born. He is best known for designing several programming languages, including Pascal, and for pioneering several classic topics in software engineering. If there is (or better 'was') one programming language that I really loved in the same way I hated it, then it was Pascal. On the one hand it was a rather easy to understand beginners programming language, but when trying to build 'real world' software projects based on Pascal, most of them in my experience were doomed to fail. The largest project based on Pascal that I was involved with was a 2 mio lines of code near realtime application for the military back in the 1990s. Everybody knew, we better should have chosen Ada or C++, but it was not our decision to use Pascal. Believe me, you wouldn't like to maintain 2 mio lines of Pascal code. Nevertheless, the concept of the language designed by Niklaus Wirth was a great achievement for computer science!
“A good designer must rely on experience, on precise, logic thinking; and on pedantic exactness. No magic will do.” (Niklaus Wirth)
Niklaus Wirth was born in Winterthur, Switzerland, in 1934. In 1959 he earned a degree in Electronics Engineering from the Swiss Federal Institute of Technology Zürich (ETH Zürich), an M.SC. from Laval University (1960), and a Ph.D. in electrical engineering and computer science from UC Berkeley (1963). Upon graduation, Wirth became an assistant professor at the newly created computer science department at Stanford University. Then in 1968 he became Professor of Informatics at ETH Zürich, where he stayed until his retirement in 1999. It was at the ETH Zürich, where he developed the programming languages Pascal (1970), Modula-2 (1979), and also Oberon (1988). Pascal was by far the most popular of them and became a widely used programming language in computer-science education. It influenced a generation of students and professional programmers. The basis of the development of Pascal was the programming language Algol-W and the desire to have a language that would satisfy the requirements of system design.

The peculiar simplicity and beauty of a Pascal program can easily be demonstrated via 'Hello World':
program HelloWorld;
begin
  writeln('Hello World');
end.

The first Pascal compiler was designed in Zurich for the CDC 6000 computer family, and it became operational in 1970. Already in 1972 Pascal was used in introductory programming courses. Wirth has contributed to both hardware and software aspects of computer design and has written influential books on software engineering and structured programming. He received the ACM Turing Award for the development of these languages and in 1994 he was inducted as a Fellow of the ACM

Niklaus Wirth also popularized the so-called Wirth's law, a computing adage in 1995. It states a simple fact that should give us computer scientists a lot to think about:
"Software is getting slower more rapidly than hardware becomes faster." (Wirth's Law)



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Thursday, February 14, 2013

Christopher Latham Sholes invented the QWERTY Typewriter

Christopher Latham Sholes
(1819 - 1890)
On February 14, 1819,  American inventor Christopher Latham Sholes was born, who invented the first practical typewriter and is responsible for the  QWERTY keyboard layout still in use today.

Christopher Latham Sholes began working as an apprentice to a printer in his teenage years and later became a newspaper publisher and politician. He started a partnership Samuel W. Soule, Charles F. Kleinstuber, and Carlos Glidden to develop a printing device, focusing on numbers at first. Unfortunately, they were not the only ones, since numerous patents were applied for globally. The curious printers and inventors around Sholes however, found that all machines broke easily and could not maintain on the market.

Their recently built numbering machine became a somewhat great success and they decided to work on a further device, assisted by the German clock builder Matthias Schwalbach and by September of 1866, a model including the full alphabet, numbers and basic punctuation was completed. They immediately began typing letters to potential buyers of their idea and found in James Densmore a decent investor. The patent for the 'typewriter' was filed on June 23, 1868 and its manufacture began in Chicago with the financial help of Densmore.

The businessmen, inventors and engineers continued their development on the machine building on work of other typewriter engineers as well. The new machines were tested on people like James Clephane, who was occupied as a stenographer and destroyed numerous machines through his heavy use. After further versions and refinements, the typewriter entered the market on July 1, 1874.

Even though numerous tests were performed the machines still lacked of reliability and were only sold 400 times by the end of 1874. It was exhibited at the Centennial Exhibition two years later, but Alexander Graham Bell clearly focused the attention on himself demonstrating the telephone. However, Mark Twain was one of the first authors to buy and use the typewriter for his works. In a letter to his brother in 1875, he noted: "I am trying get the hang of this new fangled writing machine, but am not making a shining success of it. However this is the first attempt I have ever made, & yet I perceive that I shall soon & easily acquire a fine facility in its use. . . .The machine has several virtues. I believe it will print faster than I can write. One may lean back in his chair & work it. It piles an awful stack of words on one page. It don't muss things or scatter ink blots around. Of course it saves paper."

During the years of development, the QWERTY keyboard was invented. Early versions contained a total of two rows with alphabetically ordered letters. The problem with the arrangement was that the metal arms jammed into neighboring arms when pressed either at the same time or shortly after. Commonly used letter pairs were to be separated from each other, this way the speed of typing could also be increased. After years of rearranging the letters and numbers on the keyboard and the qwerty keyboard as we know it today was born.

At yovisto you may learn more about typewriters in a demonstration of various types used in 1944 by the US Navy.



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Wednesday, February 13, 2013

ENIAC - The First Computer Introduced Into Public

The ENIAC 
On February 13, 1946, J. Presper Eckert and John Mauchly introduced Electronic Numerical Integrator and Computer, or ENIAC, the first general purpose, electronic computer. ENIAC was a giant step forward in computing technology.

Actually, the research that lead to the development of ENIAC was sponsored by the US military. The army needed a computer for calculating artillery-firing tables, the settings used for different weapons under varied conditions for target accuracy. The Ballistics Research Laboratory (BRL), the branch of the military responsible for calculating these tables, heard about John Mauchly's research at the University of Pennsylvania, who had previously created several calculating machines, some with small electric motors inside. In 1942, Mauchly had begun designing an improved calculating machine based on the work of John Atanasoff that would use vacuum tubes to speed up calculations. Finally, on May 31, 1943, the military commission on the new computer began with 32 year old John Mauchly as chief consultant and 24 year old John Presper Eckert Jr., a genius graduate student from Moore School, as chief engineer. It took the team about one year to design the ENIAC and 18 months and US$ 500,000 to build it. Nevertheless, by the time they had finished construction, the war was over. But, the ENIAC was still put to work by the military doing calculations for, as e.g., the design of hydrogen bombs, weather prediction, cosmic-ray studies, but also wind-tunnel design.

 The ENIAC combined, for the first time, the high speed of electronics with the ability to be programmed for many complex problems. It could add or subtract 5000 times a second, a thousand times faster than any other machine. It also had modules to multiply, divide, and square root. High speed memory was limited to 20 words (about 80 bytes). Built under the direction of John Mauchly and J. Presper Eckert at the University of Pennsylvania, ENIAC's development and construction lasted from 1943 to full operation at the end of 1945. The machine was huge, weighing 30 tons, and contained over 18,000 vacuum tubes. One of the major engineering feats was to minimize tube burnout, which was a common problem at that time. The machine was in almost constant use for the next ten years. ENIAC employed paper card readers obtained from IBM, by the time a long established part of IBM's business accounting machines. During operation, the ENIAC was silent but you knew it was on as the 18,000 vacuum tubes each generated waste heat like a light bulb and 174,000 watts of heat meant that the computer could only be operated in a specially designed room with its own heavy duty air conditioning system. One of the most difficult problems to solve was that ENIAC's design would require 18,000 vacuum tubes to all work simultaneously. But, vacuum tubes were notoriously unreliable. The idea that 18,000 tubes could work together was considered so unlikely that the dominant vacuum tube supplier of the day, RCA, first refused to join the project. By the time ENIAC was working, about 2000 of the computer's vacuum tubes had to be replaced each month by a team of six technicians.

ENIAC was definitively a so-called 'Turing-complete' device, i.e. it was not restricted to special problems, but could compute any problem - well, of course only if this problem would fit in the considerably small memory. A "program" on the ENIAC, however, was defined by the states of its patch cables and switches, a far cry from the stored program electronic machines that came later. Once a program was written, it had to be mechanically set into the machine. Six women did most of the programming of ENIAC. Improvements completed in 1948 made it possible to execute stored programs set in function table memory, which made programming less a "one-off" effort, and more systematic.

About 10 percent of the historic computer lives on in the same basement room where it was created. ENIAC's 50th anniversary was celebrated in 1996 with a visit by Vice President Al Gore. What was left of the old computer was fired up one last time. Today, ENIAC is generally closed but special arrangement can be made to see it by contacting the University's electrical engineering school at 33rd and Walnut. Eckert and Mauchley eventually formed their own company, which was later bought by the Rand Corporation. They produced the Universal Automatic Computer (UNIVAC), which was the first commercially available computer, but this is a completely different story...

At yovisto, you may enjoy a short documentation on ENIAC.

 
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