Fellow of the Royal Society
Fellowship of the Royal Society is an award granted to individuals that the Royal Society of London judges to have made a'substantial contribution to the improvement of natural knowledge, including mathematics, engineering science and medical science'. Fellowship of the Society, the oldest scientific academy in continuous existence, is a significant honour, awarded to many eminent scientists from history including Isaac Newton, Charles Darwin, Michael Faraday, Ernest Rutherford, Srinivasa Ramanujan, Albert Einstein, Winston Churchill, Subrahmanyan Chandrasekhar, Dorothy Hodgkin, Alan Turing and Francis Crick. More fellowship has been awarded to Stephen Hawking, Tim Hunt, Elizabeth Blackburn, Tim Berners-Lee, Venkatraman Ramakrishnan, Atta-ur Rahman, Andre Geim, James Dyson, Ajay Kumar Sood, Subhash Khot, Elon Musk and around 8,000 others in total, including over 280 Nobel Laureates since 1900; as of October 2018, there are 1689 living Fellows and Honorary Members, of which over 60 are Nobel Laureates.
Fellowship of the Royal Society has been described by The Guardian newspaper as “the equivalent of a lifetime achievement Oscar” with several institutions celebrating their announcement each year. Up to 60 new Fellows and foreign members are elected annually in late April or early May, from a pool of around 700 proposed candidates each year. New Fellows can only be nominated by existing Fellows for one of the fellowships described below: Every year, up to 52 new Fellows are elected from the United Kingdom and the Commonwealth of Nations which make up around 90% of the society; each candidate is considered on their merits and can be proposed from any sector of the scientific community. Fellows are elected for life on the basis of excellence in science and are entitled to use the post-nominal letters FRS. See Category:Fellows of the Royal Society and Category:Female Fellows of the Royal Society; every year, Fellows elect up to ten new Foreign Members. Like Fellows, Foreign Members are elected for life through peer review on the basis of excellence in science.
As of 2016 there are around 165 Foreign Members, who are entitled to use the post-nominal ForMemRS. See Category:Foreign Members of the Royal Society. Honorary Fellowship is an honorary academic title awarded to candidates who have given distinguished service to the cause of science, but do not have the kind of scientific achievements required of Fellows or Foreign Members. Honorary Fellows include Bill Bryson, Melvyn Bragg, Robin Saxby, David Sainsbury, Baron Sainsbury of Turville and Onora O'Neill. Honorary Fellows are entitled to use the post nominal letters FRS. Others including John Maddox, Patrick Moore and Lisa Jardine were elected as honorary fellows, see Category:Honorary Fellows of the Royal Society. Statute 12 is a legacy mechanism for electing members before official honorary membership existed in 1997. Fellows elected under statute 12 include 4th Earl of Selborne. Prime Ministers of the United Kingdom such as Margaret Thatcher, Neville Chamberlain,Ramsay Macdonald and H. H. Asquith were elected under statute 12, see Category:Fellows of the Royal Society.
The Council of the Royal Society can recommend members of the British Royal Family for election as Royal Fellows of the Royal Society. As of 2016 there are five royal fellows: Charles, Prince of Wales elected 1978 Anne, Princess Royal elected 1987 Prince Edward, Duke of Kent elected 1990 Prince William, Duke of Cambridge elected 2009 Prince Andrew, Duke of York elected 2013Her Majesty the Queen, Elizabeth II is not a Royal Fellow, but provides her patronage to the Society as all reigning British monarchs have done since Charles II of England. Prince Philip, Duke of Edinburgh was elected under statute 12, not as a Royal Fellow; the election of new fellows is announced annually in May, after their nomination and a period of peer-reviewed selection. Each candidate for Fellowship or Foreign Membership is nominated by two Fellows of the Royal Society, who sign a certificate of proposal. Nominations required at least five fellows to support each nomination by the proposer, criticised for establishing an old-boy network and elitist gentlemen's club.
The certificate of election includes a statement of the principal grounds on which the proposal is being made. There is no limit on the number of nominations made each year. In 2015, there were 654 candidates for election as Fellows and 106 candidates for Foreign Membership; the Council of the Royal Society oversees the selection process and appoints 10 subject area committees, known as Sectional Committees, to recommend the strongest candidates for election to Fellowship. The final list of up to 52 Fellowship candidates and up to 10 Foreign Membership candidates is confirmed by the Council in April and a secret ballot of Fellows is held at a meeting in May. A candidate is elected if she secures two-thirds of votes of those Fellows present and voting. A maximum of 18 Fellowships can be allocated to candidates from Physical Sciences and Biological Sciences. A further maximum of 6 can be ‘Honorary’, ‘General’ or ‘Royal’ Fellows. Nominations for Fellowship are peer reviewed by sectional committees, each with 15 members and a chair.
Members of the 10 sectional committees change every 3 years to mitigate in-group bias, each group covers different
California Institute of Technology
The California Institute of Technology is a private doctorate-granting research university in Pasadena, California. Known for its strength in natural science and engineering, Caltech is ranked as one of the world's top-ten universities. Although founded as a preparatory and vocational school by Amos G. Throop in 1891, the college attracted influential scientists such as George Ellery Hale, Arthur Amos Noyes and Robert Andrews Millikan in the early 20th century; the vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1921. In 1934, Caltech was elected to the Association of American Universities and the antecedents of NASA's Jet Propulsion Laboratory, which Caltech continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán; the university is one among a small group of institutes of technology in the United States, devoted to the instruction of pure and applied sciences. Caltech has six academic divisions with strong emphasis on science and engineering, managing $332 million in 2011 in sponsored research.
Its 124-acre primary campus is located 11 mi northeast of downtown Los Angeles. First-year students are required to live on campus and 95% of undergraduates remain in the on-campus House System at Caltech. Although Caltech has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations; the Caltech Beavers compete in 13 intercollegiate sports in the NCAA Division III's Southern California Intercollegiate Athletic Conference. As of October 2018, Caltech alumni and researchers include 73 Nobel Laureates, 4 Fields Medalists, 6 Turing Award winners. In addition, there are 53 non-emeritus faculty members who have been elected to one of the United States National Academies, 4 Chief Scientists of the U. S. Air Force and 71 have won the United States National Medal of Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as NASA. According to a 2015 Pomona College study, Caltech ranked number one in the U.
S. for the percentage of its graduates who go on to earn a PhD. Caltech started as a vocational school founded in Pasadena in 1891 by local businessman and politician Amos G. Throop; the school was known successively as Throop University, Throop Polytechnic Institute and Throop College of Technology before acquiring its current name in 1920. The vocational school was disbanded and the preparatory program was split off to form an independent Polytechnic School in 1907. At a time when scientific research in the United States was still in its infancy, George Ellery Hale, a solar astronomer from the University of Chicago, founded the Mount Wilson Observatory in 1904, he joined Throop's board of trustees in 1907, soon began developing it and the whole of Pasadena into a major scientific and cultural destination. He engineered the appointment of James A. B. Scherer, a literary scholar untutored in science but a capable administrator and fund raiser, to Throop's presidency in 1908. Scherer persuaded retired businessman and trustee Charles W. Gates to donate $25,000 in seed money to build Gates Laboratory, the first science building on campus.
In 1910, Throop moved to its current site. Arthur Fleming donated the land for the permanent campus site. Theodore Roosevelt delivered an address at Throop Institute on March 21, 1911, he declared: I want to see institutions like Throop turn out ninety-nine of every hundred students as men who are to do given pieces of industrial work better than any one else can do them. In the same year, a bill was introduced in the California Legislature calling for the establishment of a publicly funded "California Institute of Technology", with an initial budget of a million dollars, ten times the budget of Throop at the time; the board of trustees offered to turn Throop over to the state, but the presidents of Stanford University and the University of California lobbied to defeat the bill, which allowed Throop to develop as the only scientific research-oriented education institute in southern California, public or private, until the onset of the World War II necessitated the broader development of research-based science education.
The promise of Throop attracted physical chemist Arthur Amos Noyes from MIT to develop the institution and assist in establishing it as a center for science and technology. With the onset of World War I, Hale organized the National Research Council to coordinate and support scientific work on military problems. While he supported the idea of federal appropriations for science, he took exception to a federal bill that would have funded engineering research at land-grant colleges, instead sought to raise a $1 million national research fund from private sources. To that end, as Hale wrote in The New York Times: Throop College of Technology, in Pasadena California has afforded a striking illustration of one way in which the Research Council can secure co-operation and advance scientific investigation; this institution, with its able investigators and excellent research laboratories, could be of great service in any broad scheme of cooperation. President S
In biology, a mutation is the permanent alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements. Mutations result from errors during DNA replication or other types of damage to DNA, which may undergo error-prone repair, or cause an error during other forms of repair, or else may cause an error during replication. Mutations may result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce discernible changes in the observable characteristics of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution and the development of the immune system, including junctional diversity; the genomes of RNA viruses are based on RNA rather than DNA. The RNA viral genome can be double single stranded. In some of these viruses replication occurs and there are no mechanisms to check the genome for accuracy; this error-prone process results in mutations.
Mutation can result in many different types of change in sequences. Mutations in genes can either have no effect, alter the product of a gene, or prevent the gene from functioning properly or completely. Mutations can occur in nongenic regions. One study on genetic variations between different species of Drosophila suggests that, if a mutation changes a protein produced by a gene, the result is to be harmful, with an estimated 70 percent of amino acid polymorphisms that have damaging effects, the remainder being either neutral or marginally beneficial. Due to the damaging effects that mutations can have on genes, organisms have mechanisms such as DNA repair to prevent or correct mutations by reverting the mutated sequence back to its original state. Mutations can involve the duplication of large sections of DNA through genetic recombination; these duplications are a major source of raw material for evolving new genes, with tens to hundreds of genes duplicated in animal genomes every million years.
Most genes belong to larger gene families of shared ancestry. Novel genes are produced by several methods through the duplication and mutation of an ancestral gene, or by recombining parts of different genes to form new combinations with new functions. Here, protein domains act as modules, each with a particular and independent function, that can be mixed together to produce genes encoding new proteins with novel properties. For example, the human eye uses four genes to make structures that sense light: three for cone cell or color vision and one for rod cell or night vision. Another advantage of duplicating a gene is. Other types of mutation create new genes from noncoding DNA. Changes in chromosome number may involve larger mutations, where segments of the DNA within chromosomes break and rearrange. For example, in the Homininae, two chromosomes fused to produce human chromosome 2. In evolution, the most important role of such chromosomal rearrangements may be to accelerate the divergence of a population into new species by making populations less to interbreed, thereby preserving genetic differences between these populations.
Sequences of DNA that can move about the genome, such as transposons, make up a major fraction of the genetic material of plants and animals, may have been important in the evolution of genomes. For example, more than a million copies of the Alu sequence are present in the human genome, these sequences have now been recruited to perform functions such as regulating gene expression. Another effect of these mobile DNA sequences is that when they move within a genome, they can mutate or delete existing genes and thereby produce genetic diversity. Nonlethal mutations increase the amount of genetic variation; the abundance of some genetic changes within the gene pool can be reduced by natural selection, while other "more favorable" mutations may accumulate and result in adaptive changes. For example, a butterfly may produce offspring with new mutations; the majority of these mutations will have no effect. If this color change is advantageous, the chances of this butterfly's surviving and producing its own offspring are a little better, over time the number of butterflies with this mutation may form a larger percentage of the population.
Neutral mutations are defined as mutations whose effects do not influence the fitness of an individual. These can increase in frequency over time due to genetic drift, it is believed that the overwhelming majority of mutations have no significant effect on an organism's fitness. DNA repair mechanisms are able to mend most changes before they become permanent mutations, many organisms have mechanisms for eliminating otherwise-permanently mutated somatic cells. Beneficial mutations can improve reproductive success. Mutationism is one of several alternatives to evolution by natural selection that have existed both before and after the publication of Charles Darwin's 1859 book, On the Origin of Species. In the theory, mutation was the source of novelty
University of Nebraska–Lincoln
The University of Nebraska–Lincoln referred to as Nebraska, UNL or NU, is a public research university in the city of Lincoln, in the state of Nebraska in the Midwestern United States. It is the state's oldest university, the largest in the University of Nebraska system; the state legislature chartered the university in 1869 as a land-grant university under the 1862 Morrill Act, two years after Nebraska's statehood into the United States. Around the turn of the 20th century, the university began to expand hiring professors from eastern schools to teach in the newly organized professional colleges while producing groundbreaking research in agricultural sciences; the "Nebraska method" of ecological study developed here during this time pioneered grassland ecology and laid the foundation for research in theoretical ecology for the rest of the 20th century. The university is organized into eight colleges on two campuses in Lincoln with over 100 classroom buildings and research facilities, its athletic program, called the Cornhuskers, is a member of the Big Ten Conference.
The Nebraska football team has won 46 conference championships since 1970 and five national championships. The women's volleyball team has won five national championships along with nine other appearances in the Final Four; the Husker football team plays its home games at Memorial Stadium, selling out every game since 1962. The stadium's capacity is about 92,000 people, larger than the population of Nebraska's third-largest city; the University of Nebraska was created by an act of the Nebraska state legislature in 1869, two years after the State of Nebraska was admitted into the U. S; the law passed in 1869 creating the university described its aims: "The object of such institution shall be to afford to the inhabitants of the state the means of acquiring a thorough knowledge of the various branches of literature and the arts." The school received an initial land grant of about 130,000 acres and the campus construction began with the building of University Hall in its first year. By 1873, the University of Nebraska had offered its first two degrees to its first graduating class.
The school remained small and suffered from a lack of funds until about 20 years after its founding, when its high school programs were taken over by a new state education system. From 1890 to 1895 enrollment rose from 384 to about 1,500. A law school and a graduate school were created at about this time period, making it the first school west of the Mississippi to establish a graduate school. By 1897, the school was 15th in the nation in total enrollment. Through the turn of the 20th century, the school struggled to find an identity as both a pragmatic, frontier establishment and an academic, intellectual institution, it developed a competitive spirit in the form of a debate team, a football team, the arrival of fraternities and sororities. In 1913–14, a fierce debate ensued over whether to keep the University in downtown Lincoln or to move it out of town; the issue was not resolved until a statewide referendum sided with the downtown plan. After purchasing property downtown, the school experienced a building boom, both on the new property and on the farming campus.
The school would not experience another boom until the late 1940s, when the sudden arrival of thousands of soldiers returning from the war for an education forced the school to seek further expansion. In 1908, Nebraska was inducted as a member of the Association of American Universities, an organization of research universities. In recent years, Nebraska had been at or near the bottom of the AAU's statistical criteria for members, a ranking attributed in part to the university's extensive agricultural research funded by the U. S. Department of Agriculture, not included in the AAU's rankings because it is not awarded by peer-reviewed grants. Nebraska retained its AAU membership after a 2000 challenge; this provided Nebraska with an advantage when the Big Ten was looking to expand in 2010, as all of its members at that time were AAU members. Nebraska Chancellor Harvey Perlman said. "I doubt that our application would've been accepted had we not been a member of the." However, in 2011, after an extended campaign to retain its membership and a close, contentious vote, Nebraska became the only institution to be removed from the AAU membership by a vote of the membership In June 2018, the American Association of University Professors voted to censure the university for violations of academic freedom.
In 2017, an adjunct instructor was filmed by a student as the instructor expressed a political opinion about the student's activist activities. State lawmakers demanded that the university hold the instructor accountable and the university subsequently fired her, a move the AAUP contends was a violation of her academic freedom. University of Nebraska is governed by the Board of Regents; the board consists of eight voting members elected by district for six-year terms, four non-voting student Regents, one from each campus, who serve during their tenure as student body president. The board supervises the general operations of the university, the control and direction of all expenditures; the university today has nine colleges which offers more than 150 undergraduate majors, 20 pre-professional programs, 100 graduate programs and 275 programs of study. College of Agricultural Sciences and Natural Resources College of Architecture College of Arts and Sciences College of Business College of Education and Human Sciences College of Engineering Hixson-Lied College of Fine and Performing Arts Co
Albert Lasker Award for Basic Medical Research
The Albert Lasker Award for Basic Medical Research is one of the prizes awarded by the Lasker Foundation for the outstanding discovery and achievement in the field of medicine and Human Physiology. The award precedes a Nobel Prize in Medicine: 50% of the winners have gone on to win one
Neurospora crassa is a type of red bread mold of the phylum Ascomycota. The genus name, meaning "nerve spore" in Greek, refers to the characteristic striations on the spores; the first published account of this fungus was from an infestation of French bakeries in 1843. N. Crassa is used as a model organism because it is easy to grow and has a haploid life cycle that makes genetic analysis simple since recessive traits will show up in the offspring. Analysis of genetic recombination is facilitated by the ordered arrangement of the products of meiosis in Neurospora ascospores, its entire genome of seven chromosomes has been sequenced. Neurospora was used by Edward Tatum and George Wells Beadle in their experiments for which they won the Nobel Prize in Physiology or Medicine in 1958. Beadle and Tatum exposed N. crassa to x-rays. They observed failures in metabolic pathways caused by errors in specific enzymes; this led them to propose the "one gene, one enzyme" hypothesis that specific genes code for specific proteins.
Their hypothesis was elaborated to enzyme pathways by Norman Horowitz working on Neurospora. As Norman Horowitz reminisced in 2004, "These experiments founded the science of what Beadle and Tatum called'biochemical genetics'. In actuality, they proved to be the opening gun in what became molecular genetics and all developments that have followed from that." In the 24 April 2003 issue of Nature, the genome of N. crassa was reported as sequenced. The genome is about 43 megabases long and includes 10,000 genes. There is a project underway to produce strains containing knockout mutants of every N. crassa gene. In its natural environment, N. crassa lives in tropical and sub-tropical regions. It can be found growing on dead plant matter after fires. Neurospora is used in research around the world, it is important in the elucidation of molecular events involved in circadian rhythms and gene silencing, cell polarity, cell fusion, development, as well as many aspects of cell biology and biochemistry. Sexual fruiting bodies can only be formed.
Like other Ascomycetes, N. crassa has two mating types that, in this case, are symbolized by A and a. There is no evident morphological difference between a mating type strains. Both can form the female reproductive structure. Protoperithecia are formed most in the laboratory when growth occurs on solid synthetic medium with a low source of nitrogen. Nitrogen starvation appears to be necessary for expression of genes involved in sexual development; the protoperithecium consists of an ascogonium, a coiled multicellular hypha, enclosed in a knot-like aggregation of hyphae. A branched system of slender hyphae, called the trichogyne, extends from the tip of the ascogonium projecting beyond the sheathing hyphae into the air; the sexual cycle is initiated. Such contact can be followed by cell fusion leading to one or more nuclei from the fertilizing cell migrating down the trichogyne into the ascogonium. Since both A and a strains have the same sexual structures, neither strain can be regarded as male or female.
However, as a recipient, the protoperithecium of both the A and a strains can be thought of as the female structure, the fertilizing conidium can be thought of as the male participant. The subsequent steps following fusion of A and a haploid cells, have been outlined by Fincham and Day and Wagner and Mitchell. After fusion of the cells, the further fusion of their nuclei is delayed. Instead, a nucleus from the fertilizing cell and a nucleus from the ascogonium become associated and begin to divide synchronously; the products of these nuclear divisions migrate into numerous ascogenous hyphae, which begin to grow out of the ascogonium. Each of these ascogenous hypha bends to form a hook at its tip and the A and a pair of haploid nuclei within the crozier divide synchronously. Next, septa form to divide the crozier into three cells; the central cell in the curve of the hook contains one a nucleus. This binuclear cell is called an "ascus-initial" cell. Next the two uninucleate cells on either side of the first ascus-forming cell fuse with each other to form a binucleate cell that can grow to form a further crozier that can form its own ascus-initial cell.
This process can be repeated multiple times. After formation of the ascus-initial cell, the A and a nucleus fuse with each other to form a diploid nucleus; this nucleus is the only diploid nucleus in the entire life cycle of N. crassa. The diploid nucleus has 14 chromosomes formed from the two fused haploid nuclei that had 7 chromosomes each. Formation of the diploid nucleus is followed by meiosis; the two sequential divisions of meiosis lead to four haploid nuclei, two of the A mating type and two of the a mating type. One further mitotic division leads to four a nucleus in each ascus. Meiosis is an essential part of the life cycle of all sexually reproducing organisms, in its main features, meiosis in N. crassa seems typical of meiosis generally. As the above events are occurring, the mycelial sheath that had enveloped the ascogonium develops as the wall of the perithecium, becomes impregnated with melanin, blackens; the mature perithecium has a flask-shaped structure. A mature perithecium may contain as many as 300 asci, each derived from identical fusion diploid nuclei.
Ordinarily, in nature, when the
X-rays make up X-radiation, a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after the German scientist Wilhelm Röntgen who discovered these on November 8, 1895, credited as its discoverer, who named it X-radiation to signify an unknown type of radiation. Spelling of X-ray in the English language includes the variants x-ray, X ray. Before their discovery in 1895 X-rays were just a type of unidentified radiation emanating from experimental discharge tubes, they were noticed by scientists investigating cathode rays produced by such tubes, which are energetic electron beams that were first observed in 1869. Many of the early Crookes tubes undoubtedly radiated X-rays, because early researchers noticed effects that were attributable to them, as detailed below.
Crookes tubes created free electrons by ionization of the residual air in the tube by a high DC voltage of anywhere between a few kilovolts and 100 kV. This voltage accelerated the electrons coming from the cathode to a high enough velocity that they created X-rays when they struck the anode or the glass wall of the tube; the earliest experimenter thought to have produced. In 1785 he presented a paper to the Royal Society of London describing the effects of passing electrical currents through a evacuated glass tube, producing a glow created by X-rays; this work was further explored by his assistant Michael Faraday. When Stanford University physics professor Fernando Sanford created his "electric photography" he unknowingly generated and detected X-rays. From 1886 to 1888 he had studied in the Hermann Helmholtz laboratory in Berlin, where he became familiar with the cathode rays generated in vacuum tubes when a voltage was applied across separate electrodes, as studied by Heinrich Hertz and Philipp Lenard.
His letter of January 6, 1893 to The Physical Review was duly published and an article entitled Without Lens or Light, Photographs Taken With Plate and Object in Darkness appeared in the San Francisco Examiner. Starting in 1888, Philipp Lenard, a student of Heinrich Hertz, conducted experiments to see whether cathode rays could pass out of the Crookes tube into the air, he built a Crookes tube with a "window" in the end made of thin aluminum, facing the cathode so the cathode rays would strike it. He found that something came through, that would cause fluorescence, he measured the penetrating power of these rays through various materials. It has been suggested that at least some of these "Lenard rays" were X-rays. In 1889 Ukrainian-born Ivan Pulyui, a lecturer in experimental physics at the Prague Polytechnic who since 1877 had been constructing various designs of gas-filled tubes to investigate their properties, published a paper on how sealed photographic plates became dark when exposed to the emanations from the tubes.
Hermann von Helmholtz formulated mathematical equations for X-rays. He postulated a dispersion theory before Röntgen made his announcement, it was formed on the basis of the electromagnetic theory of light. However, he did not work with actual X-rays. In 1894 Nikola Tesla noticed damaged film in his lab that seemed to be associated with Crookes tube experiments and began investigating this radiant energy of "invisible" kinds. After Röntgen identified the X-ray, Tesla began making X-ray images of his own using high voltages and tubes of his own design, as well as Crookes tubes. On November 8, 1895, German physics professor Wilhelm Röntgen stumbled on X-rays while experimenting with Lenard tubes and Crookes tubes and began studying them, he wrote an initial report "On a new kind of ray: A preliminary communication" and on December 28, 1895 submitted it to Würzburg's Physical-Medical Society journal. This was the first paper written on X-rays. Röntgen referred to the radiation as "X"; the name stuck.
They are still referred to as such in many languages, including German, Danish, Swedish, Estonian, Japanese, Georgian and Norwegian. Röntgen received the first Nobel Prize in Physics for his discovery. There are conflicting accounts of his discovery because Röntgen had his lab notes burned after his death, but this is a reconstruction by his biographers: Röntgen was investigating cathode rays from a Crookes tube which he had wrapped in black cardboard so that the visible light from the tube would not interfere, using a fluorescent screen painted with barium platinocyanide, he noticed a faint green glow from the screen, about 1 meter away. Röntgen realized some invisible rays coming from the tube were passing through the cardboard to make the screen glow, he found they could pass through books and papers on his desk. Röntgen threw himself into investigating these unknown rays systematically. Two months after his initial discovery, he published his paper. Röntgen discovered their medical use when he made a picture of his wife's hand on a photographic plate formed due to X-rays.
The photograph of his wife's hand was the first photograph of a human body part using X-rays. When she saw the picture, she said "I have seen my death."The discovery of X-rays stimul