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1.
《Annales de Paléontologie》2019,105(3):173-190
This article relates the long scientific life of the French catholic missionary, Father/Doctor Henri Fontaine. He is also a geologist, a palaeontologist, an expert on Paleozoic corals and an archeologist. The year 2018 marked his 94th birthday, 70th sacerdotal year and 64 years of his scientific career. He has devoted most of his life to scientific activities in East and Southeast Asia: from 1954 to late 1975 in Viet Nam as geologist-expert, from 1978 to 2013 in Cambodia, China, Indonesia, Korea, Laos, Malaysia, the Philippines, Singapore, Thailand and Viet Nam, within the framework of the Coordinating Committee for Coastal and Offshore Geoscience Programmes in East and Southeast Asia (CCOP) and afterwards as a volunteer once he had retired. Until 2018, he published nearly 300 articles about geology, palaeontology and prehistory, mostly as sole author or main author. Although he initially intended to be priest living among villagers somewhere in Asia, his life evolved, in spite of himself, following spiritual, political and scientific events.  相似文献   

2.
A 29 year old white homosexual man presented with a two and a half week history of severe sore throat, fever, and extreme fatigue. His symptoms did not respond to antibiotics. He had mild bilateral conjunctivitis, a rash over his chest and back, and enlarged lymph nodes, but examination of the nervous system yielded normal results. He had low total white cell and platelet counts. The results of enzyme linked immunosorbent assay for human immunodeficiency virus (HIV) were equivocal when HIV IgM was detected in serum. Despite treatment with ampicillin his temperature remained high and he developed abnormal neurological signs, including a paraparesis and hyperreflexia of the arms. HIV was isolated from lymphocytes from blood and cerebrospinal fluid. Over the next six weeks the patient improved and was discharged. Two months later abnormal neurological signs persisted in his legs. Although various neurological syndromes associated with seroconversion to HIV have been described, this is probably the first report of a patient with myelopathy at the time of seroconversion.  相似文献   

3.
In many biological and other scientific journals, a reader's understanding of a paper to the argument of which statistical methods and analyses are important is often impeded by confusions of terminology and ambiguities of symbols. This is not solely because statistics is a difficult subject for biologists! If an editor were to formulate and make known a code of statistical symbols, abbreviations, and technical terms that in his journal will be regarded as part of the normal language of science, an author could use these without need for explanation each time. Every author would remain free to depart from the code, provided that he defined clearly his own usages. Such a policy, supported by the journal's referees, would do much to remove the frequent necessity for a reader to guess an author's meaning. Similarly considerations apply to the use of statistical software packages, where there is an evident need for an author to declare what software (if any) he has used, in much the same way as, by established custom, he will carefully specify his experimental materials and methods where these in any respect differ from the obvious. The present paper is written to stimulate constructive debate, and in no way to dogmatize on the merits or faults of particular statistical methods. Its underlying spirit is that the author of a scientific communication has a duty to describe the making of his observations, the conduct of his computations, and the performance of his computations with a clarity that would permit their repetition by another scientist who has access to the appropriate facilities and resources.  相似文献   

4.
It was my good fortune to meet personally the three invertebrate cell culture pioneers,Richard Goldschmidt,Zan-Yin Gaw,and Thomas D.C.Grace (Fig.1).In 1951 I met Goldschmidt at a symposium in Cold Spring Harbor,but I only knew that he was a prominent geneticist.I had no idea about his insect cell culture work at Yale University and daily contacts with Ross G.Harrison.In 1959 Zan Yin Gaw in Wuhan successfully cultured monolayers of silkworm cells for more than one year.I reported his breakthrough achievement at the 11th International Congress of Entomology in Vienna in 1960,but his work was completely ignored outside China.In 1982 Gaw invited me to Wuhan where he told me that he studied in the United States in the 1930s,working as postdoctoral scientist at the Rockefeller Institute,where he was daily meeting William Trager,and later at Yale University in the Osborn Laboratory,where he was inspired by Harrison.T.D.C.Grace worked in my laboratory at Rockefeller University during 1957 and 1958,then returned to CSIRO in Canberra,Australia.  相似文献   

5.
The author examined the thyroid glands of 52 aged (18 to 30 months old) and 14 young (6 months old) male rats with histophysiological methods. By means of light-microscopical examinations he observed laminated colloid, i.e. psammom bodies which contained calcium and iron, in the follicles of the thyroid glands of the old rats. Founding himself upon data of the literature, he deals with the questions of the occurrence and origin of the psammom bodies. Relying on his own examinations he is of the opinion that in the case of animals involution and dystrophic of a certain degree connected with senescence calls forth on oedema which and besides also the adenomas occurring in greater numbers means a disorder of the metabolic processes taking place in the thyroid gland and a possibility of the formation of psammom bodies. Eventually, in the authors opinion it cannot be stated with certainty -- at least in the case of animals -- that there is a close relationship between the occurrence of psammom bodies and the neoplasma.  相似文献   

6.
《Marine Micropaleontology》2004,50(1-2):149-159
Alcide Dessalines d’Orbigny was born on 6 September 1802 in Couëron (near Nantes), France. In his early youth, he developed a life interest in the study of a group of microscopic animals that he named ‘Foraminifera’. In his first scientific work, devoted to this group, he established the basis of a new science, micropaleontology. All his life, he worked on foraminifera, but his concern in natural sciences widely exceeded the domain of micropaleontology. Impressed by his first work on foraminifera, published at the age of 23, the scientists of the Muséum National d’Histoire Naturelle (MNHN) chose him as the naturalist explorer for an expedition to South America. Alcide d’Orbigny explored Brazil, Argentina, Uruguay, Chile, Bolivia, and Peru from 1826 to 1833. He was a great humanist and applied the view of an ethnologist and historian to the communities with which he shared his daily life in South America. A precursor in biogeography and ecology, he contributed greatly to the advancement of knowledge of the animal and vegetal kingdoms by describing several thousand living species in the nine volumes of his ‘Voyage dans l’Amérique Méridionale’ (1835–1847). Back in France, he turned his research towards paleontology and stratigraphy. He undertook the immense task of describing all species of fossil invertebrates found in France in the eight volumes of ‘La Paléontologie française’ (1840–1860). He arranged 18 000 species in stratigraphic order in the three volumes of ‘Prodrome de Paléontologie stratigraphique’ (1850–1852), and published three volumes entitled ‘Cours élémentaire de paléontologie et de géologie stratigraphiques’ (1849–1852). These important works led him to create the first geological and stratigraphical scale. Many of the 27 stages established are still used in the standard chronostratigraphic scale. The Chair of Paleontology of the MNHN in Paris was created for him in 1853. He died on 30 June 1857 at the age of 55, in Pierrefitte (France), leaving behind him a huge scientific and cultural heritage. Alcide d’Orbigny bequeathed to posterity a collection of more than 100 000 vegetable and animal specimens. This exceptionally rich heritage, deposited in the MNHN, is an international reference collection, and it is actively consulted by specialists from around the world. The application of his work extends to various fields of academic research (such as earth history, paleoceanography and paleoclimatology), to economics and practical applications in stratigraphy and micropaleontology that greatly contribute to oil and other resource exploration as well as major earth construction. The bicentennial of the birth of Alcide d’Orbigny was celebrated in France during the year 2002 under the patronage of the highest authorities of the state, along with scientific and cultural institutions. A traveling exhibition presented the different facets of his life’s work and international congresses were held in the three places dearest to Alcide d’Orbigny: Santa Cruz (Bolivia), La Rochelle (France) and Paris (France). This year (2003) marks the 150th anniversary of his appointment to the Chair of Paleontology of the MNHN.  相似文献   

7.
Play behavior and stress-associated behavior of a captive juvenile gorilla were observed before and after his transfer to a larger and more natural environment. The gorilla was observed for 4 months after the transfer and at 1 and 4 years after the transfer. Throughout his first month in the new environment play decreased dramatically. Although play subsequently increased again 2 months and 1 year after the transfer, it never reached the levels of play in the old environment. Four years after the move his play had decreased again to the low level of his first month in the new environment. Two of his stress-associated behaviors, coprophagy and regurgitation/reingestion, decreased after the transfer. Self-clasping behavior increased initially in the new environment and remained at high levels 1 year after the move. Four years after the move his self-clasping behavior was significantly less than at 1 year after the move; however, it continued to be significantly greater than in the old environment. These findings suggest that larger and more natural environments do not necessarily result in more play activity or a reduction in all stress-associated behavior.  相似文献   

8.
ABSTRACT: BackgoundGranulomatosis with polyangitis (Wegener's) is a vasculitic disease predominantly affecting the lungs, skin, kidneys, ears, nose and throat. Mycobacterium abscessus is an uncommon rapidly growing mycobacterium causing sporadic lung disease. This is the first report of both GPA and Mycobacterium abscessus pulmonary disease reported in the literature.Case PresentationWe present a case report of a 33 year old Caucasian man with relapsing disease complicated by pulmonary infection with Mycobacterium abscessus. He subsequently required bilateral cochlear implantation for progressive sensori-neural hearing loss. His M. abscessus was treated successfully with a prolonged course of antimicrobial therapy. His Granulomatosis with polyangitis (Wegener's) relapsed towards the end of antimicrobial therapy and required treatment. Shortly after completing his antimicrobial therapy and relapse, he developed progressive dyspnea due to pulmonary fibrosis. CONCLUSION: The potential causes of his progressive dyspnoea are discussed including the potential role of his underlying disease and treatment.  相似文献   

9.
10.
Synopsis Bill Ricker’s career went through many twists in his academic years. He had taken botany in his senior matriculation year at high school and he had collected over 100 species of flora before commencement of university life. At the conclusion of his first university year, he set out over the summer to collect a much larger sample of species, primarily from the Great Lakes-St. Lawrence ecoregion, to fulfil a requirement for a second year botany course (spermatophytes). He identified about 390 species, and some 254 were collected and pooled with those from previous years to make a final submission of 354 spermatophyte species. Field plant identification continued in each academic year thereafter, in concert with collections and identifications of aquatic invertebrates in his summer projects while under the employment of the Ontario Fisheries Research Laboratory. At the conclusion of his undergraduate years, Bill had taken more courses in botany than in zoology, and it was the summer employment that had really prepared him for postgraduate work in fisheries biology, which was ecologically oriented. When Bill left Ontario in the autumn of 1931 he had identified over 600 species of plants, excluding lower cryptogams, but including many aquatic species of higher plants. In western North America Bill’s botanical career began at Cultus Lake in 1931. He again studied all aspects of the basin while employed with the federal government, and from the work he assembled a Ph.D. thesis. At the time of thesis completion he had identified over 300 species of flora, including alpine plants at timberline, 1500 – 1800 m above lake level, and planktonic algae in its water column. In 1939, after more field fisheries work in the Fraser River basin of British Columbia, Bill accepted a position with the biological staff at Indiana University. In this period which concluded in 1950 he identified another 50 – 110 species of flora, all in the Carolinian ecoregion, and hitherto not seen by him. Considering all floral classes, Bill’s eastern North American repertoire had by then added up to 791 species, representative of more than 112 families of plants. Returning west for the remainder of his life, new identifications elsewhere added to his Cultus Lake list which slowly added up to about 1000 species for the west coastal region of North America. Flora was also identified elsewhere in the mid-continental region of North America, in Eurasia where the Abisko region of Lappland was a highlight, and in South America and New Zealand. Records of his botanical prowess, were kept primarily in his diaries, which began in 1923 and were maintained consistently to the end of 1934, and thereafter intermittently to 1949. The diaries reveal that his career as a budding botanist was subtly hijacked by a wily Professor W.H.K. Harkness in the rival Biology Department who out-manoeuvred Drs. R.B. Thompson and R.A. Sifton in the Botany Department. The former always managed to employ Bill in summer and keep him occupied in the department’s labs during the autumn and winter and spring, tying up any free time when the botanist had approached him on lab work. Certainly, the botany courses taken and which he excelled at were more appropriate for his aquatic ecological pursuits. Salesmanship won the day for the zoologists, but Bill was a life-long botanist regardless of whatever else he studied or managed throughout his professional career. The last days of his life had a botanical conclusion.  相似文献   

11.
Believe it or not, as a boy Carlo Croce liked to hang out in art museums, to his mother’s chagrin. There are a lot of art museums in Italy, so his mother started dropping him off and going off to the coffee bar to find more interesting company. He bought his first painting, an old master, at age 12 and that used all his savings. He didn't resume his old master collection until he was in his 30s and had saved some money from his job at the Wistar Institute in Philadelphia. He now has an exciting and growing collection.In the meantime, he received his MD degree from the University of Rome “La Sapienza” while reading textbooks and journals in English to supplement the old style medical education. He planned to join Karl Habel at Scripps Clinic in 1970 for a research fellowship just as Dr. Habel was struck in his prime by a monkey B virus infection, so Carlo was diverted from California to Philadelphia to join Hilary Koprowski's internationally known Wistar Institute of Anatomy and Biology. I was a Ph.D. student at Wistar at the time and witnessed the arrival of the quiet 25 yr. old Italian who was too shy to try out his textbook English.He began his work in somatic cell genetics and virology in a large laboratory where a number of us worked on related projects, including Barbara Knowles (now Associate Director for Research at Jackson Laboratory) and Davor Solter (now Director of Developmental Biology, Max Planck Institute, Freiburg, Germany).One of his first accomplishments was to map the very first viral integration site on chromosome 7q in an SV40 transformed fibroblast cell line, using human-mouse somatic cell hybrids that retained human chromosome 7, the SV40 T-antigen and the SV40 genome. Very recently, one of his hybrid clones was used by others to clone the SV40 genome integration site and to show that the SV40 genome had integrated into a common fragile site.Still using somatic cell hybrids, Carlo Croce and his laboratory began in the late 70s and early 80s to map genes important in cancer, such as the immunoglobulin genes that are rearranged in lymphomas, along with the MYC and BCL2 genes among others. These experiments took advantage of the leukemia/lymphoma specific translocation to walk from immunoglobulin loci, and later TCR loci, into the oncogene loci juxtaposed by translocation, the beginning of positional cloning of translocation breakpoints. These studies involved collaborations with valued colleagues, including Peter Nowell, the co-discoverer with David Hungerford, of the Philadelphia chromosome, the first reported cancer specific chromosome alteration. In the exciting decode of the 1980s, the Croce laboratory published 23 reports in Science, including the discovery of the BCL2 gene with Yoshiide Tsujimoto (now University of Osaka). They also observed that mistakes by immunoglobulin family rearrangement/recombination machinery was responsible for the type of chromosome translocations that involved the IG and TCR genes.Carlo Croce has been not only an outstanding laboratory scientist with numerous important discoveries to his credit; he has also been the Director of an NCI designated Cancer Center, first at the Fels Institute for Cancer Research, where he built a first class basic cancer research faculty from the ground up. In 1991, he moved his cancer research faculty to Jefferson Medical College, where it took the name of its benefactor, Sidney Kimmel, and became the Kimmel Cancer Center. At KCI the Croce laboratory continued to find and study genes involved in cancer development: oncogenes activated by translocation such as ALL1, involved in biphenotypic leukemias, discovered with another important collaborator, Eli Canaani and TCL1 (with Gianni Russo’s lab) activated by translocation to the TCRa locus in lymphomas of ataxia telangiectasia patients; or tumor suppressor genes, lost usually through deletions in epithelial cancers, such as FEZ1/LZTS1 at 8p22 lost in prostate, breast and other cancers and the FHIT gene at the 3p14.2 common fragile site (discovered in a collaboration with my laboratory), confirming a long held hypothesis that genes at chromosome fragile sites could contribute to cancer development through frequent chromosomal rearrangements. At the same time, Carlo Croce was living the nearly always tumultuous life of a Director of a Cancer Center, involving recruitment of faculty, constant bargaining with Deans, department chairman, University administrators, but he still manages to fit in a few skiing meetings, gossip sessions with colleagues like Web Cavenee, visits for good coffee, good food and TV appearances in his beloved Italy and most of all, he still manages to study, examine, buy, transport, restore, reframe and admire his old master paintings. I think he loves it as much as science because discovering a beautiful but misattributed painting at an obscure or even well known auction house, buying it and then proving that it is actually a painting by a Gentileschi or a Cavallino is as thrilling and elegant as discovering the connection between a specific gene alteration and its cancer.  相似文献   

12.
This article firstly summarizes the process of study of an old collection, which had not been considered since the excavations at the site Les Vachons, started before 1914 and completed around 1939. The studied collection of J. Coiffard, both excavator and inventor of this site, includes four-fifths of the artefacts because, in 1940, he donated approximately one fifth to the Eyzies Museum. For his part, J. Bouyssonie who participated in the excavations for 3 years gave the major part of his own collection to the Archaeological Society of Charentes Angouleme where its condition makes it difficult to analyze. Despite these restrictions, based on statistical comparisons with counts many other sites, I came to the conclusion that the top three layers of Les Vachons are a confirmation of the Gravettian model, developed by B. Bosselin and F. Djindjian through their factor analysis. This model seems much better suited to the stratigraphy of Les Vachons, than all assumptions made by previous analysts in their attempt to bring the industries from the three layers in what remains from the Peyrony model.  相似文献   

13.
The year 2011 marked the centenary of the death of one of the founders of British neurology, John Hughlings-Jackson (1835-1911). By common consent he was a great clinician. But he was more. He endeavored to use clinical observations to throw light on one of the great problems of the modern world, the problem of mind. Hughlings-Jackson's daily contact with mentalities warped by neurological disease caused him to ponder deeply the nature of the mind-brain relationship, nowadays often known simply as the "hard problem." In particular, he saw the danger of conflating mind and brain, a danger that has grown greater with the spectacular growth of neuroscientific knowledge during the last century. Although Hughlings-Jackson's neuroscientific thought is long outdated, his philosophic endeavors remain highly instructive.  相似文献   

14.
Ole Christensen, a PhD scholar in the Department of Prehistory in the Research School of Pacific Studies at the Australian National University, was killed in a car accident on his way to work on 16 December last year. Ole was a Canadian citizen of Danish birth, whose parents settled in rural Alberta. He took his BA(Hons) in 1970 and his MA in 1972, both in the Department of Archaeology at the University of Calgary. His MA thesis, ‘Banff Prehistory: prehistoric subsistence and settlement in Banff National Park, Alberta’, is evidence of an early interest in economically and ecologically oriented archaeology, which he furthered by taking courses and laboratory work in pollen analysis. A visit to South America in 1970 with an archaeological team investigating early farming settlements in the Cauca Valley, Colombia, combined with a long standing interest in Polynesian anthropology to encourage him to seek to do graduate work on tropical agricultural systems somewhere in the Pacific. When he subsequently applied for the ANU scholarship which he took up in early 1972, he seemed a highly suitable person to work in association with the Department of Prehistory's project into New Guinea Highlands' agricultural history then about to start at Kuk in the upper Wahgi valley (see Mankind, 3:177–83). The proposition put to Ole was that he should undertake a study of the hydraulic technology and agrarian organization of one of the large scale agricultural systems operating in drained swamp that still flourish in Irian Jaya at the Paniai (Wissel) Lakes and in the Baliem valley, to supplement the archaeological work in the Wahgi where such systems had once but no longer existed. He felt, however, that his ethnographic background was too slim and he chose instead to do work for which he was better trained, the study of resource utilization over time in a side valley off the Wahgi close to the site of the Department's swamp excavations. The beautifully designed project that he carried out is described in the following article by him. It is based on a seminar he gave at ANU shortly before his death. I should like to make two points about this project that the article does not stress. One is the wealth of plant materials recovered from the excavations by wet sieving every ounce of excavated soil, when the nearest water source was sometimes some hundreds of precipitous yards away. The abundant pandanus seeds found in all levels of the excavated sites and their change over time from thick-walled, allegedly wild, to thin-walled, allegedly cultivated, varieties may hold important evidence for the chronology of horticulture in New Guinea and the question of whether an independent development of plant domestication took place there. The second point I want to make is that against his expectations he found himself to be a born and insatiable ethnographic fieldworker. With his Wurup friends he surveyed and recorded all the resource zones in terms of which his selection of sites for excavation was made and took part in all the activities of food procurement and processing that were responsible for the archaeological evidence that he set out to recover and interpret. A practical man of quiet and simple tastes, he was as settled in his bush house at Wurup as in his rural retreat near Canberra. He was unassertive, tolerant and deeply sympathetic and made undemanding and unobtrusive friendships with people in both homes. He is a loss to them and to his profession. His colleagues at the University of Calgary are establishing an academic prize in his memory. To his colleagues at ANU falls the responsibility of ensuring that the important work of this promising young scholar is brought to completion.  相似文献   

15.
D J Doyle 《CMAJ》1996,154(3):382-384
Dr. John Doyle, a Toronto anesthetist, shares some recent experiences on the Internet. He explains how he became involved and how electronic mail and computer resources help in his daily clinical practice. He also explains how he and other clinicians share opinions, expertise and advice through an Internet-based discussion group devoted to his specialty.  相似文献   

16.
Given the predominance of brachiation and other forms of suspension in gibbon locomotion, we compared the locomotor, postural, and manipulative behaviors of a captive, juvenile, one‐armed gibbon to the behavioral profiles of his family members. We expected Kien Nahn, whose arm was amputated in response to an untreatable injury approximately 1 year before observations began, to avoid suspensory locomotion, to spend more time immobile, and to be less likely to exhibit postures involving forelimb suspension. Data were collected using scan sampling to record the behaviors and postures of Kien Nahn, his younger brother, and his parents. Additional postural and manipulative behaviors were recorded ad lib. Kien Nahn and his younger sibling had similar activity levels, and although differences in postural profiles existed, they were surprisingly few. Specifically, Kien Nahn spent significantly less time in motion and in non‐suspensory forms of locomotion than his brother. When compared to his parents, Kien Nahn was found to be both active and in motion more often, but was less likely to exhibit the forelimb suspension posture. Despite the increased energetic demands associated with one‐armed brachiation, Kien Nahn preferred suspensory locomotion to other forms of locomotion. Furthermore, he found unique solutions for foraging and locomoting, often making use of his feet and teeth, and he was generally the first to approach and manipulate enrichment objects. We found no evidence to suggest that Kien Nahn's injury has altered his activity levels. Although the one‐armed gibbon displayed slightly different locomotor, postural, and manipulative behaviors than his family members, he seems to have adapted well to his injury. Zoo Biol 0:1–8, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

17.
Boundaries play an important role in Richard Alba’s articulation of new assimilation theory, as is evident in the major works he has produced during the past two decades. This article traces his interest in boundaries to “The Twilight of Ethnicity among Americans of European Ancestry: The Case of Italians”, an article he published in ERS in 1985. It is in this article and a related book published the same year that one can begin to trace the evolution of his thinking on both ethnic boundaries and the cultural content contained within those boundaries.  相似文献   

18.
On 27 March 2000 Shigeru Nakano was lost in the Sea of Cortez off Bahia de Los Angeles in Baja California, when the research vessel that he and eight others were using to return from nearby islands capsized in an unexpected storm. Shigeru Nakano, Takuya Abe, and Masahiko Higashi, all faculty of the Center for Ecological Research (CER) at Kyoto University in Japan were visiting island research sites where Gary Polis of the University of California-Davis was studying food webs, and were accompanied by five other researchers and students. Nakano and his two Japanese colleagues, Polis, and Michael Rose, a postgraduate researcher, drowned. Survivors reported that Shigeru Nakano repeatedly pulled others back to the capsized boat when they were washed away by the raging sea, and strapped his own life jacket onto one of his colleagues who could not swim, literally giving his own life to save the lives of others. Nakano was a superb diver and field biologist, the best I have ever known, but I know from personal experiences during grueling field work in the mountains of Japan and Montana that he would never have left his friends to swim to the nearest island more than a kilometer away and save himself. Nakano's body was not recovered despite an extensive search effort. He was 37 years old and is survived by his wife and three children, and his parents and brother.  相似文献   

19.
Enzymatic Carboxyl Activation of Amino Acids(Hoagland, M. B., Keller, E. B., and Zamecnik, P. C. (1956) J. Biol. Chem. 218, 345–358)Mahlon Bush Hoagland was born in Boston, Massachusetts in 1921. He attended Harvard University and graduated in 1943. Knowing that he wanted to be a surgeon, Hoagland then enrolled at Harvard Medical School. However, he was diagnosed with tuberculosis, and his poor health prevented him from becoming a surgeon when he received his M.D. in 1948. Instead, he accepted a research position at Massachusetts General Hospital. In 1953, he became a postdoctoral fellow with Journal of Biological Chemistry (JBC) Classic author Fritz Lipmann (1) at Huntington Laboratories (also at Massachusetts General Hospital), and a year later, he moved to an adjoining laboratory to work on protein synthesis with JBC Classic author Paul Zamecnik (2).Open in a separate windowMahlon HoaglandInspired by Lipmann''s insights into acyl activation mechanisms, Hoagland used a cell-free system created by Zamecnik that carried out net peptide bond formation using 14C-amino acids (3) to uncover the mechanism of amino acid activation. As reported in the JBC Classic reprinted here, he isolated an enzyme fraction that, in the presence of ATP and amino acids, catalyzed the first step in protein synthesis: the formation of aminoacyl adenylates or activated amino acids. Using data from analysis of this fraction, Hoagland presented a scheme for amino acid activation in his Classic paper.A few years later, Zamecnik and Hoagland discovered a molecule that is essential for protein synthesis: tRNA. This discovery is the subject of the Zamecnik Classic (2).After the discovery of tRNA, Hoagland spent the next year (1957–1958) at Cambridge University''s Cavendish laboratories working with Francis Crick. During that year he traveled to France to visit the Institute Pasteur in Paris. Experiments begun at the Institute would, by 1960, lead to the discovery of messenger RNA (mRNA).When he returned to the United States, Hoagland was appointed associate professor of microbiology at Harvard Medical School. He remained there until 1967 when he accepted a position as professor at Dartmouth Medical School. In 1970, he became the director of the Worcester Foundation for Experimental Biology, a Massachusetts research institute founded by his father. He retired in 1985 and currently lives in Thetford, Vermont.Hoagland has received several awards and honors in recognition of his contributions to science. These include the 1976 Franklin Medal, the 1982 and 1996 Book Awards from the American Medical Writers Association, and membership in the American Academy of Arts and Sciences and the National Academy of Sciences.  相似文献   

20.
Moshe Shokeid 《Ethnos》2013,78(3-4):233-244
Anthropologists who have worked in recent decades experienced the breakdown of a dominant methodological and theoretical ethos. The author relates his pains and delights as he moved away from the Jerusalem “modernization” grand theory sociological paradigm of the 1960s to the Manchester School compelling fieldwork doctrine. And he relates his later attraction to the Geertzian genre and the more recent encounters with the mixed blessing of reflexivity and “post‐modernism”. The latter have opened new fields for exploration and liberated the anthropologist from strict disciplinarian borders and ideological taboos. But the new genres seem also to jeopardize the raison d'être of the ethnographic project. The author associates his changing loyalties and tastes with his choice of ethnographic fields.  相似文献   

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