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Gustav Hertz

Known for his collaborations with fellow colleague James Franck at the University of Berlin, German scientist Gustav Hertz (1887-1975) achieved fame and success early in life when he and Franck documented the changes in energy that occur when an electron strikes an atom. The information the two men discovered confirmed the quantum theory put forth by physicist Neils Bohr regarding the amount of energy that can be absorbed by an atom. For their work Hertz and Franck received the Nobel Prize in Physics in 1925. Hertz was also involved in some of the Soviet Union's early research into atomic energy.

Hertz was born on July 27, 1887, in Hamburg, Germany to Auguste Arning and Gustav Hertz, an attorney. His uncle, Heinrich Rudolf Hertz, had studied electromagnetic waves in the 1880s and he is the man for whom the unit of frequency is now named. Hertz first attended the Johanneum Realgymnasium in Hamburg, and after graduating in 1906 he began his college education at the University of Göttingen, majoring in mathematics and physics. He later transferred to the University of Münich and eventually ended up at the University of Berlin where he completed his education. During his studies Hertz developed an interest in the field of experimental physics and ultimately finished his studies in this field. In 1911, he graduated from the University of Berlin with a Ph.D., his doctorate studies focusing on the infrared absorption spectrum of carbon dioxide with relation to pressure and partial pressure. Bombarded Metal with Electrons

In 1913 Hertz was offered the position of research assistant at the University of Berlin's Physical Institute. It was at this post that he first met Franck. Interested in the same questions of experimental physics, the two men decided to pursue their research collaboratively. The first assignment they resolved to concentrate on involved bombarding a metal surface with a stream of electrons and then studying the emission of electrons from the metal, thereby determining the effect the impact of electrons had on atoms. They were especially interested in the changes this bombardment would have on the atomic energy level. This kind of research was similar to past studies of the photoelectric effect, which occurs when a metal surface is exposed to light energy and is measured through the emission of electrons from the metal surface. A study of the photoelectric effect was undertaken in 1902 by German physicist Philipp E. A. von Lenard, and a short time later Albert Einstein figured out a theory to explain von Lenard's data and the photoelectric effect in general. Taking this kind of experiment one step further, Hertz and Franck attempted to glean the make-up of electrons given off by a metal surface when it was bombarded by electrons instead of light.

Hertz and Franck sped up electrons by heating up a wire by means of a positively charged metal gauze placed a short distance from the wire. They forced the electrons to pass through a vapor of mercury and then placed a second wire gauze to catch the electrons that had not bumped into the mercury atoms and had therefore not lost their energy; the electrons that had lost their energy would not hit the second gauze, but would be motionless. They discovered that the loss of energy was negligible at the temperature they started from and so they increased the charge on the metal gauze and continued to track the loss of energy for electrons reaching the screen. They still measured little loss of energy as they slowly increased the voltage. The measurements remained relatively constant until they reached 4.9 volts. At that point, the electron current reaching the detector plunged almost to zero.

For a while, Hertz and Franck were at a loss as to how to interpret their results. They soon found, however, that Bohr's recently announced theory on the quantum model of the atom fit their research perfectly. Hertz and Franck came to the realization that the 4.9 volt result they observed matched up with the change between the first two electron energy levels in the mercury atom. In fact, the number 4.9 matched exactly the energy difference Bohr had predicted in his theory. The results of Hertz and Franck's experiments offered up one of the first pieces of experimental confirmation for Bohr's revolutionary new theory. This research "demonstrated the quantitative relations between the series of spectra lines and the energy losses of electrons in collision with atoms corresponding to the stationary energy states of the atoms," according to Hertz's biography posted on the Nobel Prize Website. Bohr's theory, for which the physicist had won the Nobel Prize in 1922, was an early model of the structure of the atom that has since become common knowledge. In this model the electrons traveled around a nucleus in numerous orbits which could be determined by the theory of quantum conditions. A quantum is the smallest amount by which certain physical quantities can change, especially concerned with electromagnetic radiation. It is the way in which scientists can examine and understand movement at the atomic level. Awarded the Nobel Prize for Physics

Shortly after his groundbreaking experiment was completed, Hertz was drafted into the German army; the year was now 1914 and World War I had begun. He was gravely wounded in battle in 1915, and his wound was so severe that his recuperation took over a year. At the end of World War I Hertz moved back to Berlin where, in 1917, he was offered a position as a lecturer, or privatdozent. While this proved a good position from which to gain experience, the position was, unfortunately, unpaid.

In 1919 Hertz married Ellen Dihlmann. The couple eventually had two sons, Hellmuth and Johannes, and both boys eventually became involved in physics. Hellmuth Hertz became a professor at the Technical College in Lund, and Johannes Hertz went on to work at the Institute for Optics and Spectroscopy at the German Academy of Sciences in Berlin. Fortunately for Hertz and his growing family, in 1920 he was offered a position at the Philips Incandescent Lamp Works in Eindhoven, Netherlands, and he and his family moved to the Netherlands where they stayed for five years. The Philips Incandescent Lamp Works was one of the first major corporations to establish and run a full-time research laboratory. His new employment allowed Hertz freedom to continue with his research work.

In 1925 Hertz and his family again returned to Germany, where Hertz had been offered the position of professor of physics at the University of Hale. He also took over as the director of the Physical Institute at that university. In that same year, in recognition of his earlier work with Franck, the two men were jointly awarded the 1925 Nobel Prize for Physics for their work with atomic energy.

Hertz stayed at the University of Hale for three years before he once again moved back to Berlin. In 1928 he became a professor of physics at the Charlottenburg Technical University. He was also entrusted with the task of rebuilding the school's Physics Institute, a job that required much of his time. Still, Hertz also continued his work in physics, and discovered a method of separating neon isotopes using a diffusion cascade. Moved to Soviet Union

In the 1930s National Socialism gained strength in Germany through the growth of the Nazi Party. Hertz did not approve of the fascism that was the backbone of the Nazi party and he was unwilling to pledge his allegiance to this new government. Because of this, Nazi officials forced him to resign from his position at the Charlottenburg Technical University. Despite his refusal to back the Nazi party, however, and much to his surprise, Hertz was offered a position at the Siemens and Halske Company in Berlin in 1935. He remained at that position, continuing his research, throughout World War II. Tragically, his wife Ellen died in 1941, and two years later he remarried, to Charlotte Jollasse. At the close of World War II, with the German economy now in ruins, things became increasingly turbulent in Germany, and in 1945 Hertz and his family moved to the Soviet Union.

Although Hertz had hoped to contribute to Soviet physics, he and other German colleagues who had fled Germany with him were not allowed to participate to any great extent in government-sponsored science programs. Swept up in the fervor of communism, the Soviets moved these German scientists to a remote area in Sukhumi near the Black Sea that was separated from the rest of the country. More significantly, for Hertz, was the fact that Sukhumi was far removed from the Soviet scientists he had hoped to work with. However, because he had made a commitment to work in the Soviet Union for ten years, he stayed in the Soviet Union, working on supersonics, radar, and continuing his research into atomic energy. Although he was seemingly hidden away, Hertz's work did not go unnoticed. In 1951 he won the Stalin Prize for his work on atomic energy. Hertz stayed in the Soviet Union until he finished his term of employment in 1954. After living briefly in East Germany, he was offered and accepted the position of director at the Karl Marx University's Physics Institute, located in Leipzig, Germany.

Hertz retired from Karl Marx University in 1961, at which time he was made professor emeritus. He returned for the last time to his former home in what still then East Berlin, and died there on October 30, 1975.

Throughout his life Hertz published papers detailing the research he had done, and his work furthered the work of others in the study of atomic energy. He also published frequently with other scientists, including Franck and other colleagues he worked with along the way. His papers run the gamut from the quantitative exchange of energy between electrons and atoms to the measurement of ionization potentials. He also authored some papers concerning the separation of isotopes. Hertz was a member of several prestigious scientific organizations, including the German Academy of Sciences in Berlin, and the Göttingen Academy of Sciences. In addition to receiving the Max Planck Medal from the German Physical Society, he was also named an honorary member of the Hungarian Academy of Sciences, a member of the Czechoslovakian Academy of Sciences, and was a foreign member of the Academy of Sciences of the USSR.

Walter Gilbert'''

American scientist Walter Gilbert (born 1932), who shared the Nobel Prize for Chemistry in 1980, became world famous for his groundbreaking research in the field of molecular biology. Admired by both fellow scientists and laymen, his efforts substantially advanced the field of genetic engineering. Because of his work, scientists have been able to manufacture genetic material in laboratories. When receiving his Nobel award, he was cited for developing a method for determining the sequence of nucleotide links in the chainlike molecules of nucleic acids. Later, he formed several commercial biotechnology firms, and he became involved in helping map the human genetic blueprint.

Early Life

Walter Gilbert was born on March 21, 1932, in Boston, Massachusetts, to Richard V. Gilbert, an economist, and Emma Cohen, a child psychologist. His father worked for the Office of Price Administration during World War II as part of President Franklin D. Roosevelt's administration. His mother proved to be an intellectually stimulating influence in the two-child household. When Gilbert was a boy, she would administer intelligence tests to his sister and him, and she educated him at home during his earliest years, teaching him how to read. In 1939, the family moved to Washington, D.C., where Gilbert attended public schools.

As a boy, Gilbert took an active interest in science, joining mineralogical and astronomical clubs. Naturally curious, he began performing his own experiments, once with nearly catastrophic results: when he was 12 years old, while his family lived in Virginia, he attempted a chemistry experiment that ended in an explosion of shattered glass. He suffered a slashed wrist and his mother had to take him to the hospital. According to her account, Gilbert was only concerned with determining what went wrong with the experiment.

In high school, he became fascinated with inorganic chemistry and nuclear physics. A youth of advanced intelligence, he would often skip school to go to the Library of Congress so he could read about Van de Graaf generators and atom smashers. "I decided to try and find out about these subjects, but there was nothing available in school," he recalled. "My grades were still good enough that the school didn't object too much." He also maintained his interest in astronomy and, as a teenager, he won a regional science fair in Washington, D.C. by making a telescope that photographed sun spots.

After high school, he attended Harvard University, where he majored in chemistry and physics. While in college, his interests became focused on theoretical physics. As a graduate student, he studied the theory of elementary particles and the quantum theory of fields. After one year of graduate school at Harvard, he transferred to the University of Cambridge in England for two years and received a doctorate degree in physics in 1957. His thesis involved dispersion relations for elementary particle scattering. While at Cambridge, he met James Watson, a young American scientist who had established a name for himself in scientific circles—and imprinted his name in genetic textbooks forever—with his groundbreaking work with DNA. That same year he returned to Harvard for a year of postdoctorate study. He also married Celia Stone, a poet he first met in high school. They would have two children, John Richard and Kate. After that, he became an assistant professor of physics at Harvard University. In the late 1950s and early 1960s, he taught several courses in theoretical physics. Entered Molecular Biology Field

In 1960, Gilbert reached a turning point in his life when he worked with Watson and Francois Gros on an experiment that involved the identification of messenger RNA. (The experiment uncovered new information about messenger RNA—essentially, the "messenger that relayed information from DNA to the areas in the cell where proteins are manufactured.") Gilbert found experimental research exciting, and from that point on, he continued working in molecular biology, which was a new and exciting field at the time. In 1961, Gilbert gained a great deal of notoriety when he published his first paper on messenger RNA in Nature Magazine. He soon became a tenured biophysicist at Harvard.

Following his work with RNA, he did research into protein synthesis, again uncovering new information that would advance the field. In the mid-sixties, he worked with Benno Müller-Hill. Their collaboration resulted in the isolation of the lactose repressor, the first example of a genetic control element. Again, his research findings advanced the field as well extended his notoriety to the international level. Later in that decade, working with David Dressler, he helped invent the rolling circle model, which describes one of the two ways DNA molecules duplicate themselves.

The 1970s were also an active and fruitful period for Gilbert. In that decade, he developed a technique of using gel electrophoresis that read nucleotide sequences of DNA segments. Also, he isolated the DNA fragment to which the lactose repressor is bound, studied the interaction of the bacterial RNA polymerase and the lactose repressor with DNA, developed recombinant DNA techniques, and helped develop rapid chemical DNA sequencing. In 1974, he became an American Cancer Society Professor of Molecular Biology. Late in the decade, he worked with Lydia Villa Komaroff and Argiris Efstratiadis on the bacterial strains that expressed insulin. The work he started with DNA would eventually lead to the Nobel Prize in Chemistry in the next decade. Entered the Business Arena

In 1979, Gilbert formed an alliance with businessmen and other scientists to help found Biogen, a commercial genetic-engineering research corporation. Reportedly, he approached this enterprise with the same enthusiasm he brought to his academic and research pursuits, learning as much as he could about patent laws and exploring management issues. For several years, Gilbert served as chief executive officer. However, he was often at odds with the company's board of directors and he resigned in 1984. Later, he would lend a hand in starting several other biological companies, including Myriad Genetics. A few years after he left Biogen, he founded the Genome Corporation, a company involved in human genome research. But the company went out of business after the stock market crash of 1987. Despite the failed venture, Gilbert's interest in genome research never flagged. When he left Biogen, he went back to Harvard, where he became a major and very high profile supporter of the Human Genome Project, a government-funded enterprise looking to build a complete map of the gene sequences in human DNA. Won the Nobel Prize

The next decade started with Gilbert receiving the most prestigious honor a scientist can attain. His innovative work and long list of achievements up to that point culminated in 1980 when he received a share of that year's Nobel Prize in Chemistry. Still a Harvard professor at the time, he shared the award with Professor Frederick Sanger, of Cambridge University in Great Britain, and Paul Berg, of Stanford University in California. They were honored for independently developing a method for determining the sequence of nucleotide links in the chainlike molecules of the nucleic acids DNA and RNA. Their work added a great deal to the worlds knowledge about how DNA, as a carrier of the genetic traits, directs the chemical machinery of the cell. Working separately in their own labs, Gilbert and Sanger developed different methods to determine the exact sequence of the nucleotide building blocks in DNA. Together, their work resulted in the creation of effective tools that enabled continued investigations into the structure and function of the genetic material. Sought the Origin of Genes

After Gilbert resigned from Biotech in 1984, he returned to Harvard University. Beginning in 1985, he worked as a professor in the university's departments of physics, biophysics, biochemistry, and biology. Former students fondly recalled studying under him. Gilbert's labs and classrooms provided an exciting atmosphere where all were considered equals, including the world famous educator himself. Students enjoyed working with Gilbert, as they found that he encouraged camaraderie, demonstrated humor, and possessed an infectious personality.

Gilbert also worked in Harvard's Department of Molecular and Cellular Biology where, with fellow staff members, he became involved in research, discovery, and training in biological areas including cellular biology, biochemistry, neurobiology, genetics, and bioinformatics. This led him to research involving molecular evolution and the development of the theory of the intron/exon gene structure. Essentially, Gilbert set out to discover the origins of genes and how they evolved. It is believed that such a theory, if eventually proven correct, could impact drug design, as it may allow scientists to recognize and manipulate the working parts within proteins.

Essentially, the purpose of the research was to discover where genes may have come from and what the first genes were like. In the course of the work, Gilbert came up with terms for the interrupted pattern in which genes are stored. In the intron/exon theory, exons refer to the working parts, while introns refer to the regions in between where the cell has to splice out. If the theory is proven correct, some believe the history of life on earth could be deduced from the DNA of modern genes. The intron/exon theory is somewhat controversial and has not gained total acceptance. In response, Gilbert employed extensive computer and statistical analysis to try and support it. Fellow scientist Philip Sharp, a molecular biologist at the Massachusetts Institute of Technology, who first discovered the primordial introns, an accomplishment that won him a Nobel Prize in Physiology or Medicine in 1993, remarked that solving the mystery may be impossible, but he gave Gilbert a vote of confidence: "That won't stop Wally Gilbert, of course… . [He] captured the imagination of the field, and still has it, I think.

What Gilbert has tried to do is to find out how the first genes were assembled in the "organic soup oceans that once covered the entire world and gave rise to life." Obviously, this is a daunting task. Modern genes contain a great deal of information, and to determine precisely how they evolved by examining their structure would be a lengthy and complex process. However, Gilbert feels the first genetic elements were simple components that predate the modern exons. The early exons became mixed and matched and constructed into long chains that would make increasingly larger genes. He believes that by studying the structure of modern genes, we could see find the early components and then determine how the mixing and matching process occurred. In his theory, the introns would be the elements that could make the mixing and matching possible.

Kristine San Antonio I-St.Gertrude