The A-DNA double helix molecular model of Crick and Watson ( consistent with their X-ray data ) for which they, with M . H . F . Wilkins, received a Nobel Prize.
32.
Structural information is generated from X-ray diffraction studies of oriented DNA fibers with the help of molecular models of DNA that are combined with crystallographic and mathematical analysis of the X-ray patterns.
33.
In 1951, the chemist Linus Pauling in California published his model of the amino acid alpha helix, a result that grew out of Pauling's efforts in X-ray crystallography and molecular model building.
34.
In 1865, German chemist August Wilhelm von Hofmann was the first to make stick-and-ball molecular models, which he used in lecture at the Royal Institution of Great Britain, such as methane shown below:
35.
"' Molecular models of DNA structures "'are representations of the molecular geometry and CPK models ) made of plastic, metal wires for " skeletal models ", graphic computations and animations by computers, artistic rendering.
36.
B-DNA X-ray patterns also supported the presence " in vivo " of the double-helical DNA configurations as proposed by Crick and Watson for their double-helix molecular model of DNA in the prior two pages of " Nature ".
37.
Crick described what he saw as the failure of Wilkins and Franklin to cooperate and work towards finding a molecular model of DNA as a major reason why he and Watson eventually made a second attempt to do so.
38.
The PS3's high speed and efficiency introduced other opportunities for worthwhile optimizations according to Amdahl's law, and significantly changed the tradeoff between computing efficiency and overall accuracy, allowing the use of more complex molecular models at little added computing cost.
39.
The development of the first correct double helix molecular model of DNA by Crick and Watson may not have been possible without the biochemical evidence for the nucleotide base-pairing ( [ A---T ]; [ C---G ] ), or Chargaff's rules.
40.
For large molecules, the R-factor usually ranges between 0.6 ( when computed for a random model and against an experimental data set ) and 0.2 ( for example for a well refined macro-molecular model at a resolution of 2.5 �ngstr�m ).
