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F-Zero GX is a futuristic racing video game for the Nintendo GameCube console. The first video game collaboration between Nintendo and Sega, it was released in Japan, North America and Europe in 2003. F-Zero AX (pictured), the arcade counterpart of GX, uses hardware conceived from a business alliance between Nintendo, Namco and Sega. F-Zero GX runs on an enhanced version of the engine used in Super Monkey Ball. The game continues the difficult, high-speed racing style of the F-Zero series, retaining the basic gameplay and control system from the Nintendo 64 game. A heavy emphasis is placed on track memorization and reflexes, which aids in completing the game. GX introduces a "story mode" element, where the player assumes the role of F-Zero pilot Captain Falcon through nine chapters while completing various missions. The game received critical acclaim as one of the best racers of its time and the greatest racer on the GameCube platform. Overall, the game was well received by critics for its visuals, intense action, high sense of speed and track design. Complaints centered on its sharp increase in difficulty that may alienate players. (Full article...)
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F-ゼロGXは、任天堂ゲームキューブコンソールの未来レースゲームです。任天堂とセガの間に最初のビデオゲームのコラボレーションが、それは2003年に日本、北米、欧州で発売された。 F-ゼロAX(写真)、GXのアーケードカウンターパートは、任天堂、ナムコとセガの間で業務提携から構想のハードウェアを使用しています。 F-ゼロGXスーパーモンキーボールで使用されるエンジンの拡張バージョンで実行されます。ゲームは任天堂64のゲームからの基本的なゲームプレイと制御システムを維持し、F-ゼロシリーズの困難な、ハイスピードレーシングスタイルを続けています。重い重点は、ゲームを完成に役立つトラック暗記と反射神経、上に置かれている。 GXは、様々なミッションを完了しながらプレイヤーは9章をF-ゼロパイロットキャプテンファルコンの役割を想定して、 "ストーリーモード"要素を、紹介します。ゲームはその時間とゲームキューブのプラットフォーム上で最大のレーサーの最高のレーサーの一つとして、批評家の称賛を受けた。全体的に、ゲームはよく、そのビジュアル、激しいアクション、スピード、トラックデザインのハイセンスための批評家によって受信されました。苦情が選手を遠ざけることが困難で、その急激な増加を中心に。 (全記事...)
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生涯と学績[編集]
ロザリンド・フランクリンは、ロンドンのユダヤ人家系の銀行家の家庭に6人きょうだいの長女として生まれた。大叔父にハーバート・サミュエル、叔父にノーマン・ベントウィッチがいる。裕福な両親は、ロザリンド9歳のときから寄宿学校に入学させ、可能なかぎり最高の教育をうけさせた[1]。
寄宿学校卒業後はケンブリッジ大学のニューナム・カレッジで学んだ。当時、ケンブリッジ大学は女子とユダヤ人の入学を認めてからそれほど時間が経過しておらず、いまだ女性が自由に研究に没頭する環境になかった。しかしロザリンドは研究にいそしみ、大学をトップクラスで卒業し、さらに大学院に進んだ[1]。第二次世界大戦中は石炭の結晶構造に関する研究をおこない、1945年、25歳のときケンブリッジで物理化学の博士号を取得している。1947年には、ケンブリッジ時代に親しかったフランス人エイドリアン・ワイルの協力を得てパリの国立化学研究所に移った。ここでは黒鉛の結晶学的研究をおこなった。
フランス留学後の1950年、ロンドン大学のキングス・カレッジに研究職を得て、X線結晶学の研究に没頭した。X線結晶学とは、結晶へのX線照射による物質の散乱パターンを逆フーリエ解析を用いて解き、当該物質の分子構造を解明していこうというものである。彼女にあたえられた研究テーマは、X線によるDNA結晶の解析であった。
ロザリンドは順調に研究を進め、着手後およそ1年で、DNAには水分含量の差によって2タイプ(A型とB型)存在することを明らかにし、それを互いに区別して結晶化する方法を確立させた。また、そこにX線を照射して散乱パターンの写真撮影に成功していた。さらに、これらについてはデータを公表せず数学的解析を自力で進めていた。1953年には、DNAの二重らせん構造の解明につながるX線回折写真を撮影している[注釈 1]。
しかし、フランクリンはDNAの研究をめぐり、彼女が来る以前からDNAを研究していたモーリス・ウィルキンスとしばしば衝突していた。そして、ウィルキンスはケンブリッジ大学キャベンディッシュ研究所に在籍していたジェームズ・ワトソンとフランシス・クリックに彼女の撮影した写真を見せる。このことは、二重らせん構造解明の手がかりとなったものの、のちに大問題となった[1]。
この時の事情について、ワトソンとウィルキンスの言い分は異なっている。ワトソンは、著書『二重らせん』で、ウィルキンスがフランクリンと険悪な関係に陥ったために写真を自分たちにこっそり見せた、と述べている。しかし、ウィルキンスは著書『二重らせん 第3の男』で、あくまでフランクリンのデータを閲覧する権限が自分にあり、フランクリンもそれを認めていた、と釈明している[1]。
また、フランクリンは1952年に自分の非公開研究データをまとめたレポートを年次報告書として英国医学研究機構に提出しているが、その研究レポートは、英国医学研究機構の予算権限を持つメンバーの一人でありクリックの指導教官にあたる立場の研究者であるマックス・ペルーツが入手し、そこからクリックの手に渡った。この非公開レポートには、DNA結晶の生の解析データだけでなく、フランクリン自身の手による測定数値や解釈も書き込まれており、DNAの結晶構造を示唆するものであった。この件についてクリックは何も語っていない[2]。
1962年にワトソン、クリック、ウィルキンスがDNAの構造解明によりノーベル生理学・医学賞を受賞したが、フランクリンは1958年に37歳の若さで卵巣癌と巣状肺炎により死亡したため、受賞の栄誉は得られなかった。一説には、実験のため無防備に大量のX線を浴びたことが癌の原因だといわれている[2]。
フランクリンは、ワトソンの『二重らせん』で「気難しく、ヒステリックなダークレディ」と書かれるなど長い間否定的な評価をされてきたが、1980年代に入ってようやく彼女の業績が再評価されるようになった[注釈 2]。2008年には、コロンビア大学からホロウィッツ賞が遺贈された。
人物[編集]
若いころのロザリンドは登山を趣味としていた。結婚はしておらず、生涯独身であった。
脚注[編集]
注釈[編集]
1.^ 福岡伸一は、彼女はワトソンやクリックとは異なり、あくまでも「帰納的に」DNAの構造を解明していくことだけを考えていたと説明している。福岡(2007) 2.^ 福岡伸一は、DNAの二重らせん構造について、「"ワトソン・クリック・フランクリン構造”とよぶべき」と述べている。福岡(2007)
Rosalind Franklin
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Rosalind E. Franklin
Rosalind Franklin.jpg
Born Rosalind Elsie Franklin 25 July 1920 Notting Hill, London
Died 16 April 1958 (aged 37) Chelsea, London Ovarian cancer
Nationality British
Fields X-ray crystallography
Institutions British Coal Utilisation Research Association Laboratoire central des services chimiques de l'État King's College London Birkbeck College, London
Alma mater Newnham College, Cambridge
Known for Fine structure of coal and graphite, Structure of DNA, structure of viruses
Rosalind Elsie Franklin (25 July 1920 – 16 April 1958)[1] 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.[2] 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"[3] to formulate Crick and Watson's 1953 hypothesis regarding the structure of DNA.[4] 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.[5] 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.[6] 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.[7]
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
Rosalind Franklin
Scientist
Rosalind Elsie Franklin 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. Wikipedia
Born: July 25, 1920, Notting Hill, United Kingdom
Died: April 16, 1958, Chelsea, Royal Borough of Kensington and Chelsea, United Kingdom
Full name: Rosalind Elsie Franklin
Education: University of Cambridge (1945), More
Siblings: Colin Franklin, Jenifer Glynn, David Franklin, Roland Franklin
Parents: Ellis Arthur Franklin, Muriel Frances Waley
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Early life and education
Franklin was born in Notting Hill, London,[8] into an affluent and influential British Jewish family.[9] Her father was Ellis Arthur Franklin (1894–1964), a London merchant banker, and her mother was Muriel Frances Waley (1894–1976). Rosalind was the elder daughter, and the second child of the family of five children. Her father's uncle was Herbert Samuel (later Viscount Samuel) who was the Home Secretary in 1916 and the first practising Jew to serve in the British Cabinet.[10]
He was also the first High Commissioner (the effective governor) for the British Mandate of Palestine. As High Commissioner (and Zionist), he surreptitiously paved the way for developing Palestine into a Jewish Homeland and ultimately an independent Jewish state ("A Broken Trust: Herbert Samuel, Zionism and the Palestinians" by Sahar Huneidi). Her aunt Helen Carolin Franklin was married to Norman de Mattos Bentwich, who was the Attorney General in the British Mandate of Palestine.[11] She was active in trade union organisation and the women's suffrage movement, and was later a member of the London County Council.[12][13] Franklin herself later became an agnostic.[14][15]
From early childhood, Franklin showed exceptional scholastic abilities. She was educated at St Paul's Girls' School [16][17] where she excelled in science, Latin[18] and sports.[19] Her family was actively involved with a Working Men's College, where Ellis Franklin, her father, taught electricity, magnetism, and the history of the Great War in the evenings and later became the vice-principal.[20][21] Later Franklin's family helped settle Jewish refugees from Europe who had escaped the Nazis.[13]
Cambridge, Kingston and Paris
Franklin went up to Newnham College, Cambridge, in 1938 and studied chemistry within the Natural Sciences Tripos. One of the demonstrators who taught her was the spectroscopist W.C. Price. Later, he was one of her senior colleagues at King's College.[22] In 1941 she was awarded Second Class Honours in her Finals. This was accepted as a bachelor's degree in the qualifications for employment. Cambridge started to award the titular B.A. and M.A. to women in 1947, and the previous women graduates received these retroactively.[23]
Franklin was awarded a research fellowship and, according to an entry on the web site of the Dolan DNA Learning Center of the Cold Spring Harbor Laboratory, that is supported by the National Cancer Institute, "She spent a year in R.G.W. Norrish's lab without great success."[24] Later, he received a Nobel Prize for his contributions to chemical kinetics.
Franklin continued to meet the requirements of the National Service Act by working as an Assistant Research Officer at the British Coal Utilisation Research Association (BCURA). The BCURA was located on the Coombe Springs Estate, near Kingston upon Thames on the southwestern outskirts of London. Professor Norrish was a wartime advisor to BCURA. John G. Bennett was the Director. Marcello Pirani and Victor Goldschmidt, both refugees from the Nazis, were consultants and lectured at BCURA while Franklin was there.[2]
She studied the porosity of coal, comparing its density to that of helium. Through this, she discovered the relationship between the fine constrictions in the pores in coals and the permeability of the pore space. By concluding that substances were expelled in order of molecular size as temperature increased, Franklin helped classify coals and accurately predict their performance for fuel purposes and in the production of wartime devices (i.e. gas masks).[25] This work was the basis of her Ph.D. thesis The physical chemistry of solid organic colloids with special reference to coal for which Cambridge University awarded her a Ph.D. in 1945. It was also the basis of several papers.[2]
The French scientist Adrienne Weill was one of Franklin's tutors at Newnham. At the end of the war, according to Sayre, Franklin asked Weill to let her know of job openings for "a physical chemist who knows very little physical chemistry, but quite a lot about the holes in coal". At a conference in the fall of 1946, Weill introduced Franklin to Marcel Mathieu, a director of the Centre National de la Recherche Scientifique (CNRS), the network of institutes that comprise the major part of the scientific research laboratories supported by the French government. This led to Franklin's appointment with Jacques Mering at the Laboratoire Central des Services Chimiques de l'Etat in Paris.
Mering was an X-ray crystallographer who applied X-ray diffraction to the study of rayon and other amorphous substances, in contrast to the thousands of regular crystals that had been studied by this method for many years.[2] He taught her the practical aspects of applying X-ray crystallography to amorphous substances. This presented new challenges in the conduct of experiments and the interpretation of results. Franklin applied them to further problems related to coal, in particular the changes to the arrangement of atoms when it is converted to graphite.[2] Franklin published several further papers on this work. It became part of the mainstream of work on the physics and chemistry of coal, covered by a current monograph,[26] the annual[27] and other publications. Mering also continued the study of carbon in various forms, using X-ray diffraction and other methods.[28]
King's College London
Double Helix[hide]
Dna-split2.png
William Astbury
Oswald Avery
Francis Crick
Erwin Chargaff
Jerry Donohue
Rosalind Franklin
Raymond Gosling
Phoebus Levene
Friedrich Miescher
Sir John Randall
Alex Stokes
James Watson
Maurice Wilkins
Herbert Wilson
v·
t· e
In January 1951, Franklin started working as a research associate at King's College London in the Medical Research Council's (MRC) Biophysics Unit, directed by John Randall.[29] Although originally she was to have worked on X-ray diffraction of proteins and lipids in solution, Randall redirected her work to DNA fibres before she started working at King's since Franklin was to be the only experienced experimental diffraction researcher at King's in 1951.[30][31] He made this reassignment, even before she started working at King's, because of the following pioneering work by Maurice Wilkins and Raymond Gosling – a Ph.D. student assigned to help Franklin.[32][33]
Even using crude equipment, these two men had obtained an outstanding diffraction picture of DNA which sparked further interest in this molecule. Wilkins and Gosling had been carrying out X-ray diffraction analysis of DNA in the unit since May 1950, but Randall had not informed them that he had asked Franklin to take over both the DNA diffraction work and guidance of Gosling's thesis.[34] Randall's lack of communication about this reassignment significantly contributed to the well documented friction that developed between Wilkins and Franklin.[35]
Franklin, working with her student Raymond Gosling,[36] started to apply her expertise in X-ray diffraction techniques to the structure of DNA. She used a new fine focus X-ray tube and microcamera ordered by Wilkins, but which she refined, adjusted and focused carefully. Drawing upon her physical chemistry background, Franklin also skillfully manipulated the critical hydration of her specimens.[37] When Wilkins inquired about this improved technique, Franklin replied in terms which offended Wilkins as Franklin had "an air of cool superiority".[38]
Franklin's habit of intensely looking people in the eye while being concise, impatient and directly confrontational to the point of abrasiveness unnerved many of her colleagues. In stark contrast, Wilkins was very shy, and slowly calculating in speech while he avoided looking anyone directly in the eye.[39] In spite of the intense atmosphere, Franklin and Gosling discovered that there were two forms of DNA: at high humidity (when wet), the DNA fibre became long and thin; when it was dried it became short and fat.[40][41]
These forms were termed DNA "B" and "A" respectively. Because of the intense personality conflict developing between Franklin and Wilkins, Randall[42] divided the work on DNA. Franklin chose the data rich A form while Wilkins selected the "B" form[43][44] because his preliminary pictures had hinted it might be helical. He showed tremendous insight in this assessment of preliminary data. The X-ray diffraction pictures taken by Franklin at this time have been called, by J. D. Bernal, "amongst the most beautiful X-ray photographs of any substance ever taken".[40]
By the end of 1951 it was generally accepted at King's that the B form of DNA was a helix, but after she had recorded an asymmetrical image in 1952 May, Franklin became unconvinced that the A form of DNA was helical in structure.[45] In July 1952, as a practical joke on Wilkins (who frequently expressed his view that DNA was helical), Franklin and Gosling produced a death notice regretting the 'death' of helical crystalline DNA (A-DNA).[46] During 1952, Rosalind Franklin and Raymond Gosling worked at applying the Patterson function to the X-ray pictures of DNA they had produced.[47] This was a long and labour-intensive approach but would yield significant insight into the structure of the molecule.[48][49]
By January 1953, Franklin had reconciled her conflicting data, concluding that both DNA forms had two helices, and had started to write a series of three draft manuscripts, two of which included a double helical DNA backbone (see below). Her two A form manuscripts reached Acta Crystallographica in Copenhagen on 6 March 1953,[50] one day before Crick and Watson had completed their model.[51] Franklin must have mailed them while the Cambridge team was building their model, and certainly had written them before she knew of their work. On 8 July 1953 she modified one of these "in proof", Acta articles "in light of recent work" by the King's and Cambridge research teams.[52]
The third draft paper on the "B" form of DNA, dated 17 March 1953, was discovered years later amongst her papers, by Franklin's Birkbeck colleague, Aaron Klug. He then published an evaluation of the draft's close correlation with the third of the original trio of 25 April 1953 Nature DNA articles.[53] Klug designed this paper to complement the first article he had written defending Franklin's significant contribution to DNA structure.[54] He had written this first article in response to the incomplete picture of Franklin's work depicted in Watson's 1968 memoir, The Double Helix.
As vividly described in The Double Helix, on 30 January 1953, Watson travelled to King's carrying a preprint of Linus Pauling's incorrect proposal for DNA structure. Since Wilkins was not in his office, Watson went to Franklin's lab with his urgent message that they should all collaborate before Pauling discovered his error. The unimpressed Franklin became angry when Watson suggested she did not know how to interpret her own data. Watson hastily retreated, backing into Wilkins who had been attracted by the commotion. Wilkins commiserated with his harried friend and then changed the course of DNA history with the following disclosure. Without Franklin's permission or knowledge, Wilkins showed Watson Franklin's famous photograph 51. Watson, in turn, showed Wilkins a prepublication manuscript by Pauling and Corey.[55] Franklin and Gosling's photo 51 gave the Cambridge pair critical insights into the DNA structure, whereas Pauling and Corey's paper described a molecule remarkably like their first incorrect model.
DNA modelling
In February 1953, Francis Crick and James D. Watson of the Cavendish Laboratory in Cambridge University had started to build a model of the B form of DNA using similar data to that available to both teams at King's. Much of their data were derived directly from research done at King's by Wilkins and Franklin. Franklin's research was completed by February 1953, ahead of her move to Birkbeck, and her data were critical.[56] Model building had been applied successfully in the elucidation of the structure of the alpha helix by Linus Pauling in 1951,[43][57] but Franklin was opposed to prematurely building theoretical models, until sufficient data were obtained properly to guide the model building. She took the view that building a model was to be undertaken only after enough of the structure was known.[45][58]
Ever cautious she wanted to eliminate misleading possibilities. Photographs of her Birkbeck work table[59] show that she routinely used small molecular models, although certainly not ones on the grand scale successfully used at Cambridge for DNA. In the middle of February 1953, Crick's thesis advisor, Max Perutz gave Crick a copy of a report written for a Medical Research Council biophysics committee visit to King's in December 1952, containing many of Franklin's crystallographic calculations.[60]
Since Franklin had decided to transfer to Birkbeck College and Randall had insisted that all DNA work must stay at King's, Wilkins was given copies of Franklin's diffraction photographs by Gosling. By 28 February 1953 Watson and Crick felt they had solved the problem enough for Crick to proclaim (in the local pub) that they had "found the secret of life".[61] However they knew they must complete their model before they could be certain.[62]
Watson and Crick finished building their model on 7 March 1953, one day before they received a letter from Wilkins stating that Franklin was finally leaving and they could put "all hands to the pump".[63] This was also one day after Franklin's two A form papers had reached Acta Crystallographica. Wilkins came to see the model the following week, according to Maddox on 12 March, and allegedly informed Gosling on his return to King's.[64]
It is uncertain how long it took for Gosling to inform Franklin at Birkbeck, but her original 17 March B form manuscript does not reflect any knowledge of the Cambridge model. Franklin did modify this draft later before publishing it as the third in the trio of 25 April 1953 Nature articles. On 18 March,[65] in response to receiving a copy of their preliminary manuscript, Wilkins penned the following "I think you're a couple of old rogues, but you may well have something".[66]
Crick and Watson then published their model in Nature on 25 April 1953 in an article describing the double-helical structure of DNA with only a footnote acknowledging "having been stimulated by a general knowledge of" Franklin and Wilkin's 'unpublished' contribution.[67] Actually, although it was the bare minimum, they had just enough specific knowledge of Franklin and Gosling's data upon which to base their model. As a result of a deal struck by the two laboratory directors, articles by Wilkins and Franklin, which included their X-ray diffraction data, were modified and then published second and third in the same issue of Nature, seemingly only in support of the Crick and Watson theoretical paper which proposed a model for the B form of DNA.[68][69] Franklin left King's College London in March 1953 to move to Birkbeck College in a move that had been planned for some time.[47]
Weeks later, on 10 April, Franklin wrote to Crick for permission to see their model.[70] Franklin retained her scepticism for premature model building even after seeing the Crick–Watson model, and remained unimpressed. She is reported to have commented, "It's very pretty, but how are they going to prove it?" As an experimental scientist Franklin seems to have been interested in producing far greater evidence before publishing-as-proven a proposed model. As such her response to the Crick–Watson model was in keeping with her cautious approach to science.[71]
However, as documented above, she did not hesitate to publish preliminary ideas about DNA in Acta, even before they could be definitively proven. Most of the scientific community hesitated several years before accepting the double helix proposal. At first mainly geneticists embraced the model because of its obvious genetic implications.
Broader acceptance for the DNA double helix did not start until about 1960, and was not openly acknowledged until 1961 during the 1962 Nobel prize nominations. It took Wilkins and his colleagues about seven years to collect enough data to prove and refine the proposed DNA structure. According to the 1961 Crick–Monod letter cited above, this experimental proof, along with Wilkins having initiated the DNA diffraction work, were the reasons why Crick felt that Wilkins should be included in the DNA Nobel prize.
Birkbeck College
An electronmicrograph of tobacco mosaic virus.
Franklin's work in Birkbeck involved the use of x-ray crystallography to study the structure of the tobacco mosaic virus (TMV) as a senior scientist with her own research group, funded by the Agricultural Research Council (ARC).[72] She was recruited by physics department chair J. D. Bernal,[73] a brilliant crystallographer who happened to be an Irish communist, known for promoting women crystallographers. In 1954 Franklin began a longstanding and successful collaboration with Aaron Klug.[74] In 1955 Franklin had a paper published in the journal Nature, indicating that TMV virus particles were all of the same length.[75] This was in direct contradiction to the ideas of the eminent virologist Norman Pirie, though her observation ultimately proved correct.[76]
Franklin, and the research group she headed, focused on the structure of RNA, a molecule equally central to life as DNA. RNA actually constitutes the genome (central information molecule) of many viruses, including tobacco mosaic virus. She assigned the study of rod-like viruses such as TMV (tobacco mosaic virus) to her PhD student Kenneth Holmes, while her colleague Aaron Klug worked on spherical viruses with his student John Finch, with Franklin coordinating and overseeing the work.[77]
Franklin also had a research assistant, James Watt, subsidised by the National Coal Board and was now the Leader of the "ARC group at Birkbeck.[78] By the end of 1955 her team had completed a model of the TMV, to be exhibited at the upcoming Brussels World's fair. The Birkbeck team members were working on RNA viruses affecting several plants, including potato, turnip, tomato and pea.[79] Franklin and Donald Caspar produced a paper each in Nature that taken together demonstrated that the DNA in TMV is wound along the inner surface of the hollow virus.[80][81]
Her former colleagues at Birkbeck College, London Aaron Klug, John Finch and Kenneth Holmes moved to the Laboratory of Molecular Biology, Cambridge in 1962.
Illness and death
In mid-1956, while on a work-related trip to the United States, Franklin first began to suspect a health problem—she found she could no longer do up her skirt because of a lump around her abdomen.[82] An operation in September of the same year revealed two tumours in her abdomen.[83] After this period and other periods of hospitalization, Franklin spent time convalescing with various friends and family members. These included Anne Sayre, Francis Crick, his wife Odile, with whom Franklin had formed a strong friendship,[84] and finally with the Roland and Nina Franklin family where Rosalind's nieces and nephews bolstered her spirits.
Franklin chose not to stay with her parents because her mother's uncontrollable grief and crying upset her too much. Even while undergoing cancer treatment, Franklin continued to work, and her group continued to produce results – seven papers in 1956 and six more in 1957.[85] In 1957, the group was also working on the polio virus and had obtained funding from the Public Health Service of the National Institutes of Health in the United States for this.[86]
At the end of 1957, Franklin again fell ill and she was admitted to the Royal Marsden Hospital. She returned to work in January 1958, and she was given a promotion to Research Associate in Biophysics.[87] She fell ill again on March 30, and she died on April 16, 1958, in Chelsea, London,[88][89] of bronchopneumonia, secondary carcinomatosis, and ovarian cancer. Exposure to X-ray radiation is sometimes considered to be a possible factor in her illness.[90]
Other members of her family have died of cancer, and the incidence of gynaecological cancer is known to be disproportionately high among Ashkenazi Jews.[91] Her death certificate read: A Research Scientist, Spinster, Daughter of Ellis Arthur Franklin, a Banker.[92]
Controversies after death
Various controversies surrounding Rosalind Franklin came to light following her death.
Allegations of sexism
Sayre states "In 1951 ... King's College as an institution, was not distinguished for the welcome that it offered to women ... Rosalind ... was unused to purdah [a religious and social institution of female seclusion] ... there was one other woman scientist on the laboratory staff" (page 96, lines 8 to 10; page 97, line 4;page 99, footnote). Andrzej Stasiak states "Sayre's book became widely cited in feminist circles for exposing rampant sexism in science."[93] Farooq Hussain states "there were seven women in the biophysics department ... Jean Hanson became an FRS, Dame Honor B. Fell, Director of Strangeways Laboratory, supervised the biologists".[94] Maddox states, (page 134, final paragraph) "Randall ... did have many women on his staff ... they found him ... sympathetic and helpful."
Sayre states "that while the male staff at King's lunched in a large, comfortable, rather clubby dining room" the female staff of all ranks "lunched in the student's hall or away from the premises".[95][96] Elkin states that most of the MRC group typically ate lunch together (including Franklin) in the mixed dining room discussed below.[97] And Maddox states, of Randall, "He liked to see his flock, men and women, come together for morning coffee, and at lunch in the joint dining room, where he ate with them nearly every day."
Claustrophobia has been cited as an unrecognised confound to some interpersonal issues attributed to sexism.[94][98] Nevertheless, sexism is said to pervade the memoir of one peer, James Watson, in his book The Double Helix published 10 years after Franklin's death and after Watson had returned from Cambridge to Harvard.[99] In this, he denigrates her work and frequently refers to her in patronizing terms as "Rosy", a name she never used. Much later, at Cambridge, Francis Crick acknowledges, "I'm afraid we always used to adopt – let's say, a patronizing attitude towards her." And another Cambridge colleague, Peter Cavendish, wrote in a letter, "Wilkins is supposed to be doing this work; Miss Franklin is evidently a fool."
Franklin herself is said to have been "not immune to the sexism rampant in these circles." In a letter to her parents in January 1939, she called one lecturer "very good, though female."[100][dubious – discuss]
Contribution to the model of DNA
One of Rosalind Franklin's important contributions to the Crick and Watson model was her lecture at the seminar in November 1951, where she presented to those present, among them Watson, the two forms of the molecule, type A and type B, and her position whereby the phosphate units are located in the external part of the molecule. She also specified the amount of water to be found in the molecule in accordance with other parts of it, data that have considerable importance in terms of the stability of the molecule. Franklin was the first to discover and formulate these facts, which in fact constituted the basis for all later attempts to build a model of the molecule.
The other contribution included an X-ray photograph of B-DNA (called photograph 51),[101] that was briefly shown to James Watson by Maurice Wilkins in January 1953,[102][103] and a report written for an MRC biophysics committee visit to King's in December 1952 which was shown by Dr. Max Perutz at the Cavendish Laboratory to both Crick and Watson. This MRC report contained data from the King's group, including some of Rosalind Franklin's and Raymond Gosling's work, and was given to Francis Crick — who was working on his thesis on haemoglobin structure — by his thesis supervisor Max Perutz, a member of the visiting committee.[104][105]
Maurice Wilkins had been given photograph 51 by Rosalind Franklin's Ph.D. student Raymond Gosling, because she was leaving King's to work at Birkbeck. There was allegedly nothing untoward in this transfer of data to Wilkins,[106][107] since the Director Sir John Randall had insisted that all DNA work belonged exclusively to King's and had instructed Franklin in a letter to even stop thinking about it.[108] Also it was implied by Horace Freeland Judson, incorrectly, that Maurice Wilkins had taken the photograph out of Rosalind Franklin's drawer.[109] However, the B-DNA X-ray pattern photograph in question was shown to Watson by Wilkins — without Franklin's permission.
Likewise Max Perutz saw "no harm" in showing an MRC report containing the conclusions of Franklin and Gosling's X-ray data analysis to Crick, since it had not been marked as confidential, although – in the customary British manner in which everything official is considered secret until it is deliberately made public – "The report was not expected to reach outside eyes".[110] Indeed, after the publication of Watson's The Double Helix exposed Perutz's act, he received so many letters questioning his judgment that he felt the need to both answer them all[111] and to post a general statement in Science excusing himself on the basis of being "inexperienced and casual in administrative matters".[112]
Perutz also claimed that the MRC information was already made available to the Cambridge team when Watson had attended Franklin's seminar in November 1951. A preliminary version of much of the important material contained in the 1952 December MRC report had been presented by Franklin in a talk she had given in November 1951, which Dr. Watson had attended but not understood.[113][114] This seems to be a rather tenuous claim. There is a significant difference between the results Franklin achieved at the end of 1951 (at the time of the seminar) and those she held when editing the report – at the end of 1952. It was a year in which her knowledge substantially increased. This and more, Watson and Crick received the report from Perutz during February, 1953, a short time after Watson received Franklin’s type B photograph, no. 51. Thus, there is no doubt that the report helped them to analyze Franklin’s correct data, which explain this and other photographs.
The Perutz letter was as said one of three letters, published with letters by Wilkins and Watson, which discussed their various contributions. Watson clarified the importance of the data obtained from the MRC report as he had not recorded these data while attending Franklin's lecture in 1951. The upshot of all this was that when Crick and Watson started to build their model in February 1953 they were working with critical parameters that had been determined by Franklin in 1951, and which she and Gosling had significantly refined in 1952, as well as with published data and other very similar data to those available at King's. Rosalind Franklin was probably never aware that her work had been used during construction of the model,[115] but Maurice Wilkins was.
Recognition of her contribution to the model of DNA
Upon the completion of their model, Francis Crick and James Watson had invited Maurice Wilkins to be a co-author of their paper describing the structure.[116][117] Wilkins turned down this offer, as he had taken no part in building the model.[118] Maurice Wilkins later expressed regret that greater discussion of co-authorship had not taken place as this might have helped to clarify the contribution the work at King's had made to the discovery.[119] There is no doubt that Franklin's experimental data were used by Crick and Watson to build their model of DNA in 1953 (see above). Some, including Maddox as cited next, have explained this citation omission by suggesting that it may be a question of circumstance, because it would have been very difficult to cite the unpublished work from the MRC report they had seen.[120]
Indeed a clear timely acknowledgment would have been awkward, given the unorthodox manner in which data were transferred from King's to Cambridge. However, methods were available. Watson and Crick could have cited the MRC report as a personal communication or else cited the Acta articles in press, or most easily, the third Nature paper that they knew was in press. One of the most important accomplishments of Maddox's widely acclaimed biography is that Maddox made a well-received case for inadequate acknowledgement. "Such acknowledgement as they gave her was very muted and always coupled with the name of Wilkins".[121]
Twenty five years after the fact, the first clear recitation of Franklin's contribution appeared as it permeated Watson's account, The Double Helix, although it was buried under descriptions of Watson's (often quite negative) regard towards Franklin during the period of their work on DNA. This attitude is epitomized in the confrontation between Watson and Franklin over a preprint of Pauling's mistaken DNA manuscript.[122] Watson's words impelled Sayre to write her rebuttal, in which the entire chapter nine, "Winner Take All" has the structure of a legal brief dissecting and analyzing the topic of acknowledgement.[123]
Sayre's early analysis was often ignored because of perceived feminist overtones in her book. It should be noted that in their original paper, Watson and Crick do cite the X-ray diffraction work of both Wilkins and Franklin. In addition, they admit their, "having been stimulated by a knowledge of the general nature of the unpublished experimental work of [groups led by both Wilkins and Franklin]".[124] Franklin and Raymond Gosling's own publication in the same issue of Nature was the first publication of this more clarified X-ray image of DNA.[125]
Franklin's part in the discovery of the nature of DNA was shown in the 1987 TV Movie Life Story, starring Tim Pigott-Smith as Francis Crick, Alan Howard as Maurice Wilkins, Jeff Goldblum as James Watson, and Juliet Stevenson as Rosalind. This movie portrayed Franklin as somewhat stern, but also alleged that Watson and Crick did use a lot of her work to do theirs.
A play entitled 'Rosalind: A Question of Life' was written by Deborah Gearing to mark the work of Rosalind, and was first published by Faber in 2006. Another play, Photograph 51 by Anna Ziegler, has been produced at several places in the USA. Ziegler's version of the 1951–53 'race' for the structure of DNA sometimes emphasizes the pivotal role of Franklin's research and her personality. Although sometimes altering history for dramatic effect, the play nevertheless illuminates many of the key issues of how science was and is conducted. False Assumptions by Lawrence Aronovitch is a play about the life of Marie Curie in which Franklin is portrayed as frustrated and angry at the lack of recognition for her scientific contributions.[126]
Nobel Prize
Franklin was never nominated for a Nobel Prize.[127] She had died in 1958 and was ineligible for nomination to the Nobel Prize in 1962 which was subsequently awarded to Crick, Watson, and Wilkins in 1962.[128][129] The award was for their body of work on nucleic acids and not exclusively for the discovery of the structure of DNA.[130] By the time of the award Wilkins had been working on the structure of DNA for more than 10 years, and had done much to confirm the Watson–Crick model.[131] Crick had been working on the genetic code at Cambridge and Watson had worked on RNA for some years.[132]
Posthumous recognition
Rosalind Franklin University of Medicine and Science1982, Iota Sigma Pi designated Franklin a National Honorary Member.[133] 1992, English Heritage placed a blue plaque on the house that Rosalind Franklin grew up in.[134] 1993, King's College London renamed the Orchard Residence at their Hampstead Campus on Kidderpore Avenue Rosalind Franklin Hall. 1995, Newnham College dedicated a residence in her name and put a bust of her in its garden.[134] 1997, Birkbeck, University of London School of Crystallography opened the Rosalind Franklin Laboratory.[135] 1997,The asteroid 9241 Rosfranklin, discovered in 1997, was named in her honour. 1998, National Portrait Gallery in London added Rosalind Franklin's portrait next to those of Francis Crick, James Watson and Maurice Wilkins.[134][136] 2000, King's College London opened the Franklin–Wilkins Building in honour of Dr. Franklin's and Professor Wilkins's work at the college.[137] King's had earlier, in 1994, also named one of the Halls in Hampstead Campus residences in memory of Rosalind Franklin. 2001, The American National Cancer Institute established the Rosalind E. Franklin Award for Women in Science.[138] 2003, the Royal Society established the Rosalind Franklin Award, for an outstanding contribution to any area of natural science, engineering or technology.[139] 2004, Finch University of Health Sciences/The Chicago Medical School, located in North Chicago, Illinois, changed its name to the Rosalind Franklin University of Medicine and Science.[140] 2004, University of Groningen in the Netherlands started the Rosalind Franklin Fellowships to promote the hiring of young, promising, female researchers. 2005, the wording on the DNA sculpture (which was donated by James Watson) outside Clare College, Cambridge's Thirkill Court is a) on the base: i) "These strands unravel during cell reproduction. Genes are encoded in the sequence of bases." and ii) "The double helix model was supported by the work of Rosalind Franklin and Maurice Wilkins.", as well as b) on the helices: i) "The structure of DNA was discovered in 1953 by Francis Crick and James Watson while Watson lived here at Clare." and ii) "The molecule of DNA has two helical strands that are linked by base pairs Adenine – Thymine or Guanine – Cytosine."[141] 2008, Columbia University awarded an Honorary Horwitz Prize to Rosalind Franklin, Ph.D., posthumously, "for her seminal contributions to the discovery of the structure of DNA".[142] 2012, Rosalind Franklin honored as namesake of Rosalind, an online project teaching programming via molecular biology. 2013, Google honoured Rosalind Franklin with a doodle showing her gazing at a double helix structure of DNA with an X ray of Photo 51 beyond it.[143]
Publications
Rosalind Franklin produced a number of publications, some cited a number of times. A representative sample is listed below. The last two publications in this list were published posthumously. ロザリンド・フランクリン
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ロザリンド・フランクリン (Rosalind Elsie Franklin)
人物情報
誕生
Rosalind Elsie Franklin
1920年7月25日
イギリスの旗 ロンドン
死没 1958年4月16日(満37歳没) イギリスの旗 ロンドン
居住 イギリスの旗 イギリス フランスの旗 フランス
国籍 イギリスの旗 イギリス
学問
研究分野
化学
研究機関 国立化学研究所 ロンドン大学
母校 ケンブリッジ大学卒業 ケンブリッジ大学大学院修了
主な業績 X線によるデオキシリボ核酸の 結晶構造の解析
影響を与えた者 ジェームズ・ワトソン フランシス・クリック
主な受賞歴 名誉ホロウィッツ賞(2008年) テンプレートを表示
ロザリンド・エルシー・フランクリン(Rosalind Elsie Franklin、1920年7月25日 - 1958年4月16日)は、イギリスの物理化学者、結晶学者である。石炭やグラファイト、DNA、タバコモザイクウイルスの化学構造の解明に貢献した。
目次
1 来歴 1.1 生い立ち
1.2 研究者として 1.3 没後
2 人物 3 家族・親族 4 脚注 4.1 注釈 4.2 参照
5 参考文献 6 評伝 7 外部リンク
来歴[編集]
生い立ち[編集]
ロザリンド・フランクリンは、ロンドンのユダヤ人家系の銀行家の家庭に6人きょうだいの長女として生まれた。大叔父にハーバート・サミュエル、叔父にノーマン・ベントウィッチがいる。裕福な両親は、ロザリンド9歳のときから寄宿学校に入学させ、可能なかぎり最高の教育をうけさせた[1]。
寄宿学校卒業後はケンブリッジ大学のニューナム・カレッジで学んだ。当時、ケンブリッジ大学は女子とユダヤ人の入学を認めてからそれほど時間が経過しておらず、いまだ女性が自由に研究に没頭する環境になかった。しかしロザリンドは研究にいそしみ、大学をトップクラスで卒業し、さらに大学院に進んだ[1]。第二次世界大戦中は石炭の結晶構造に関する研究をおこない、1945年、25歳のときケンブリッジで物理化学の博士号を取得している。1947年には、ケンブリッジ時代に親しかったフランス人エイドリアン・ワイルの協力を得てパリの国立化学研究所に移った。ここでは黒鉛の結晶学的研究をおこなった。
研究者として[編集]
フランス留学後の1950年、ロンドン大学のキングス・カレッジに研究職を得て、X線結晶学の研究に没頭した。X線結晶学とは、結晶へのX線照射による物質の散乱パターンを逆フーリエ解析を用いて解き、当該物質の分子構造を解明していこうというものである。彼女にあたえられた研究テーマは、X線によるDNA結晶の解析であった。
ロザリンドは順調に研究を進め、着手後およそ1年で、DNAには水分含量の差によって2タイプ(A型とB型)存在することを明らかにし、それを互いに区別して結晶化する方法を確立させた。また、そこにX線を照射して散乱パターンの写真撮影に成功していた。さらに、これらについてはデータを公表せず数学的解析を自力で進めていた。1953年には、DNAの二重らせん構造の解明につながるX線回折写真を撮影している[注釈 1]。
しかし、フランクリンはDNAの研究をめぐり、彼女が来る以前からDNAを研究していたモーリス・ウィルキンスとしばしば衝突していた。そして、ウィルキンスはケンブリッジ大学キャベンディッシュ研究所に在籍していたジェームズ・ワトソンとフランシス・クリックに彼女の撮影した写真を見せる。このことは、二重らせん構造解明の手がかりとなったものの、のちに大問題となった[1]。
この時の事情について、ワトソンとウィルキンスの言い分は異なっている。ワトソンは、著書『二重らせん』で、ウィルキンスがフランクリンと険悪な関係に陥ったために写真を自分たちにこっそり見せた、と述べている。しかし、ウィルキンスは著書『二重らせん 第3の男』で、あくまでフランクリンのデータを閲覧する権限が自分にあり、フランクリンもそれを認めていた、と釈明している[1]。
また、フランクリンは1952年に自分の非公開研究データをまとめたレポートを年次報告書として英国医学研究機構に提出しているが、その研究レポートは、英国医学研究機構の予算権限を持つメンバーの一人でありクリックの指導教官にあたる立場の研究者であるマックス・ペルーツが入手し、そこからクリックの手に渡った。この非公開レポートには、DNA結晶の生の解析データだけでなく、フランクリン自身の手による測定数値や解釈も書き込まれており、DNAの結晶構造を示唆するものであった。この件についてクリックは何も語っていない[2]。
没後[編集]
1962年にワトソン、クリック、ウィルキンスがDNAの構造解明によりノーベル生理学・医学賞を受賞したが、フランクリンは1958年に37歳の若さで卵巣癌と巣状肺炎により死亡したため、受賞の栄誉は得られなかった。一説には、実験のため無防備に大量のX線を浴びたことが癌の原因だといわれている[2]。
フランクリンは、ワトソンの『二重らせん』で「気難しく、ヒステリックなダークレディ」と書かれるなど長い間否定的な評価をされてきたが、1980年代に入ってようやく彼女の業績が再評価されるようになった[注釈 2]。2008年には、コロンビア大学からホロウィッツ賞が遺贈された。
人物[編集]
若いころのロザリンドは登山を趣味としていた。結婚はしておらず、生涯独身であった。
家族・親族[編集] ハーバート・サミュエル(大叔父) ノーマン・ベントウィッチ(叔父)
脚注[編集]
注釈[編集]
1.^ 福岡伸一は、彼女はワトソンやクリックとは異なり、あくまでも「帰納的に」DNAの構造を解明していくことだけを考えていたと説明している。福岡(2007) 2.^ 福岡伸一は、DNAの二重らせん構造について、「"ワトソン・クリック・フランクリン構造”とよぶべき」と述べている。福岡(2007)
参照[編集]
[ヘルプ]
1.^ a b c d 福岡(2007)pp.108-116 2.^ a b 福岡(2007)pp.117-130
参考文献[編集] 福岡伸一『生物と無生物のあいだ』講談社<講談社現代新書>、2007年5月。ISBN 978-4-06-149891-4
評伝[編集] 『ロザリンド・フランクリンとDNA―ぬすまれた栄光』:アン・セイヤー著/深町 眞理子訳(草思社、1979年/1月) ISBN-10: 4794200986 ISBN-13: 978-4794200983 (絶版) 『ダークレディと呼ばれて-二重らせん発見とロザリンド・フランクリンの真実』:ブレンダ・マドックス著 /福岡伸一訳(化学同人、2005年)ISBN 978-4759810363
外部リンク[編集] Rosalind Elsie Franklin - Find A Grave 隠された科学者-ロザリンド・フランクリン- (福岡伸一) (PDF)-数研出版サイエンスネット(2007年11月号)
執筆の途中です この項目は、化学に関連した書きかけの項目です。この項目を加筆・訂正などしてくださる協力者を求めています(プロジェクト:化学/Portal:化学)。
カテゴリ: イギリスの化学者
生物物理学者
分子生物学者
キングス・カレッジ・ロンドンの教員
ユダヤ系イギリス人
ロンドン出身の人物
1920年生
1958年没