MOLECULAR
A
REVOLUTION 1877-1955
very was born in Halifax, Nova Scotia 1877. Despite a promising career in the church, offered to him through his father, he desired greater intellectual stimulation. His frustration in his inability to help some of his patients motivated him to devote his career to the systematic effort to understand the biological activities of bacteria. This could only be attained by knowing their chemical composition.
Avery made his legacy along with a fellow colleague at the institute. McCarty and Avery concentrated on the phenomenon of pneumococcal transformation, in which R-form (non virulent) bacteria changed into the S-form (virulent) when killed S-form bacteria were added to the culture. The changed bacteria were identical in virulence and type to the killed bacteria and the changes were permanent and inheritable.
Avery’s early work came to the attention of the director of the Hospital of the Rockefeller Institute for Medical Research. In 1913 he focused most of his research for the next thirty-five years on a single species of pneumonia-creating bacteria, Diplococcus pneumoniae. There he worked along some of the elite in their fields, including Rene Dubos, Maclyn McCarty, Colin MacLeod and Alphonse R Dochez. However it was in 1944 that
Soon after this discovery, Avery and McCarty soon isolated this transforming substance from their samples of the pneumococci and discovered the substance to be deoxyribnonucleic acid. Or DNA. The paper proved that the transforming principle or heredity material, was DNA and not protein as most scientists had assumed. Avery played an early and critical role in the molecular revolution in biology.
B
orn into an esteemed academic background in 1885, Bohr already had a deep seeded interest in physics. While he was still a student he won the Academy of Sciences in Copenhagen’s prize for his experimental and theoretical investigation into oscillating fluid jets. This genius carried on in his early years, where in 1912 whilst working with Rutherford in his Manchester lab. Using Rutherford’s discovery of the atomic nucleus and Quantum Theory as established by Planck, he succeeded in working out and presenting a picture of atomic structure that still serves as an elucidation of the physical and chemical properties of the elements. He introduced the theory that electrons travelling in orbits around the atom’s nucleus. The chemical properties of each element being largely determined
by the number of electrons in the outer orbits of atoms. Bohr also intriduced the idea that an electron could drop from a higher energy orbit to a lower one, in the process emitting a photon. This became the new basis for Quantum Theory. During the Nazi occupation of Denmark in World War II, Bohr escaped to Sweden and spent the last two years of the war in England and America. When he went further west to America, he became associated with the Atomic Energy Project. He opposed the use of nuclear energy for destructive means and was awarded for his relentless papers, letters and essays on the subject. Without Bohr’s incredible intellect, moral standing or inquisitive mind, the knowledge we have now in regards to technology and materials would not even be. Bohr-illiant.
D
arwin was born into a wealthy and sophisticated family, his paternal grandfather was the well known physician and savant Erasmus Darwin. His story is an odd one, considering he started his career in medicine at Edinburgh, then dropped out in preperation to become a clergyman in Cambridge. After graduating in 1831, the young Darwin was taken aboard the HMS Beagle as an unpaid naturalist on a scientific expedition around the world. On his travels, he began fitting many of his observations into Lyell’s uniformitarian view. Lyell was a geologist who maintained that the earth’s surface is undergoing constant change, the result of natural forces operating uniformly over long periods. Darwin however, realised that some of his own observations of fossils, living plants and animals
cast doubt on the Lyell supported views that species were specifically created. For example, certain fossils of supposedly extinct species closely resembled living species in the same geographical area. In the Galapogos Islands he also observed that each island supported its own form of tortoise, mockingbird and finch. The various forms were closely related but differed in structure and eating habits from island to island. This formed the basis for Darwin’s vast conceptual scheme. This included the theory of evolution by natural selection where the young born to any species intensely compete for survival, any favourable traits are passed on to the next generation. As well as the concept that all related organims are descended from common ancestors. He also provided additional support to the earth is not static, but evolving.
H
opper came from a family with military traditions and was incredibly competent in the field of mathematics. She married a professor in 1930 and had begun teaching at Vassar in 1931, achieving the rank of associative professor. In 1943 she resigned her post to join the Navy WAVES (Women Accepted for Voluntary Emergency Service) where she soon rose to the rank of lieutenant. She reported to the Bureau of Ordnance Computation Project at Harvard University where Howard H. Aiken famously greeted her: “Here, complete the coefficients of the arc tangent series by next Thursday�. She did, compiling a 500 page manual of operations for the Automatic Sequence Controlled Calculator. At the end of WWII she was already working on the MK II version of the machine.
By the time UNIVAC-1, the first commercially available computer in 1956, she had already contributed to the complex construction of primary and advanced computer programming. Her best known contribution to computing was the invention of the compiler, the intermediate program that translates English language instructions into the language of the target computer. Her work foreshadowed enormous amounts of developments that are now the bones of digital computing: subroutines, formula translation, relative addressing, the linking loader, code optimization and even symbolic manipulation. The new discipline of computing and the sciences that depend upon it have led the way in making space for women’s participation on an equal basis, all down to Grace Hopper.
B
orn in Croatia to an Orthodox priest and a household appliance inventor, Tesla studied at the Realschule, Karlstadt in 1873.
He began his career as an electrical enginer with a phone company in Budapest. It was there that Tesla was walking through the city park that the elusive solution to the rotating magnetic field flashed through his mind. With a stick he drew a diagram in the sand explaining to his friend the principle of the induction motor. Unable to impress anyone with his radical device, he accepted an offer to work for Thomas Edison in New York. This soon turned into a bitter rivalry though, as Tesla had developed a polyphase alternating current system as opposed to Edisons direct current system. The AC/DC war came to a swift close, as AC was the superior technology.
Soon after, Tesla invented the Tesla coil, which is widely used today in radio, television and various other electronic equipment. Although it is held in high regard that his alternating current induction motor is considered one of the ten greatest discoveries of all time. Among his discoveries and patents are the flourescent light, laser beam, wireless transmission of electrical energy,r remote control, robotics, Tesla’s turbines and vertical take-off aircraft. He is considered to be the father of the radio and modern electrical transmissions systems, registered over 700 patents worldwide and was known to be an eccentric and inquisitive individual. His vision foresaw solar energy, hydroelectricity, interplanetary communications and satellites.