Rosalind Franklin's 93rd Birthday

Rosalind Elsie Franklin (25 July 1920 – 16 April 1958) was a British biophysicist and X-ray crystallographer who made critical contributions to the understanding of the fine molecular structures of DNA, RNA, viruses, coal, and graphite. Her DNA work achieved the most fame because DNA (deoxyribonucleic acid) plays an essential role in cell metabolism and genetics, and the discovery of its structure helped her co-workers understand how genetic information is passed from parents to children.

Franklin is best known for her work on the X-ray diffraction images of DNA which led to the discovery of the DNA double helix. Her data, according to Francis Crick, were "the data we actually used" to formulate Crick and Watson's 1953 hypothesis regarding thestructure of DNA. Franklin's images of X-ray diffraction confirming the helical structure of DNA were shown to Watson without her approval or knowledge. Though this image and her accurate interpretation of the data provided valuable insight into the DNA structure, Franklin's scientific contributions to the discovery of the double helix are often overlooked. Unpublished drafts of her papers (written just as she was arranging to leave King's College London) show that she had independently determined the overall B-form of the DNA helix and the location of the phosphate groups on the outside of the structure. Moreover, Franklin personally told Crick and Watson that the backbones had to be on the outside, which was crucial since before this both they and Linus Pauling had independently generated non-illuminating models with the chains inside and the bases pointing outwards. However, her work was published third, in the series of three DNA Nature articles, led by the paper of Watson and Crick which only hinted at her contribution to their hypothesis.

After finishing her portion of the work on DNA, Franklin led pioneering work on the tobacco mosaic virus and the polio virus. She died in 1958 at the age of 37 of ovarian cancer.

Hari Anak Nasional 2013

Rembrandt van Rijn's 407th Birthday

Rembrandt Harmenszoon van Rijn (Dutch: [ˈrɛmbrɑnt ˈɦɑrmə(n)soːn vɑn ˈrɛin]  15 July 1606– 4 October 1669) was aDutch painter and etcher. He is generally considered one of the greatest painters and printmakers in European art history and the most important in Dutch history.^] His contributions to art came in a period of great wealth and cultural achievement that historians call theDutch Golden Age when Dutch Golden Age painting, although in many ways antithetical to the Baroque style that dominated Europe, was extremely prolific and innovative.

Having achieved youthful success as a portrait painter, Rembrandt's later years were marked by personal tragedy and financial hardships. Yet his etchings and paintings were popular throughout his lifetime, his reputation as an artist remained high, and for twenty years he taught many important Dutch painters. Rembrandt's greatest creative triumphs are exemplified especially in his portraits of his contemporaries, self-portraits and illustrations of scenes from the Bible. His self-portraits form a unique and intimate biography, in which the artist surveyed himself without vanity and with the utmost sincerity.

In his paintings and prints he exhibited knowledge of classical iconography, which he molded to fit the requirements of his own experience; thus, the depiction of a biblical scene was informed by Rembrandt's knowledge of the specific text, his assimilation of classical composition, and his observations of Amsterdam's Jewish population. Because of his empathy for the human condition, he has been called "one of the great prophets of civilization.