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Mary Orr 《Annals of science》2014,71(2):206-240
Since first appearance, reviews and accounts of The Fresh-Water Fishes of Great Britain (1828–1838) have been surprisingly few. All agree that this rare work is remarkable for its illustrations. Its importance as a whole in the history of ichthyology, however, is largely unknown, or ignored. This article therefore constitutes the first study of the textual and contextual significance of The Fresh-Water Fishes of Great Britain. By examining in chronological order where, and by whom, the work was first reviewed and referenced until the 1860s, the extraordinary contributions that its author, Sarah Bowdich, made to ichthyology at the forefront of the field in the late 1820s can better be appreciated. Indeed, this multiple evidence demonstrates Sarah Bowdich's merits as an ichthyologist of the first order, and as the first woman ichthyologist. But establishing the significance of The Fresh-Water Fishes of Great Britain for the history of ichthyology then raises a further question. Why has it and its author been so ignored or forgotten? By returning for answers to the fields of ichthyology already considered, the article proposes that Sarah Bowdich's different angles on fish offer lines of investigation that are still important for the field today.  相似文献   

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An early example is von Neumann's and Charney's Princeton Meteorological Project in the period 1946–53 which ended with daily numerical prediction in less than 2 hours. After this stage, the questions of long-range forecasting and general circulation of the atmosphere became of greater importance. The late 1950s saw the emergence of an alternative: were atmospheric models used mainly for prediction or understanding? This controversial debate in particular occurred during an important colloquium in Tokyo in 1960 which gathered together J. Charney, E. Lorenz, A. Eliassen, and B. Saltzman, among others, and witnessed discussions on statistical methods for predictions and/or maximum simplification of dynamic equations. This phase ended in 1963 with Lorenzs seminal paper on “Deterministic non periodic flows.” (Received February 11, 2000)  相似文献   

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Konjac glucomannan beads have been investigated as metal biosorbent for Pb(Ⅱ)from aqueous solutions.The effect of contact time,solution pH,initial metal concentration,and desorption were studied in batch experiments at 20°C±2°C. Maximum mental sorption was found to occur at initial pH 4.0-5.5.Kinetic studies revealed that the initial uptake was rapid and equilibrium was established in 3 h and that the data followed the prseudo-second order reaction.The equilibrium sorption data at initial pH 4.0 were descri...  相似文献   

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Alzheimer’s disease (AD) is a neurodegenerative disorder occurring in the elderly. It is widely accepted that the amyloid beta peptide (Aβ) aggregation and especially the oligomeric states rather than fibrils are involved in AD onset. We used infrared spectroscopy to provide structural information on the entire aggregation pathway of Aβ(1–40), starting from monomeric Aβ to the end of the process, fibrils. Our structural study suggests that conversion of oligomers into fibrils results from a transition from antiparallel to parallel β-sheet. These structural changes are described in terms of H-bonding rupture/formation, β-strands reorientation and β-sheet elongation. As antiparallel β-sheet structure is also observed for other amyloidogenic proteins forming oligomers, reorganization of the β-sheet implicating a reorientation of β-strands could be a generic mechanism determining the kinetics of protein misfolding. Elucidation of the process driving aggregation, including structural transitions, could be essential in a search for therapies inhibiting aggregation or disrupting aggregates.  相似文献   

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Summary A strain ofClaviceps purpurea, labelled 231 F.I., produced in submerged culture 1200 /ml of a mixture of peptidic alkaloids composed for 30% by -ergokryptine. Cultural media, conditions of culture and development features of a typic fermentation are reported.  相似文献   

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Lithium iron phosphate(LiFePO4)was synthesized from LiOH,FeSO4 and H3PO4 by a hydrothermal process at 180℃.The samples were characterized by X-ray diffraction,scanning electron microscopy and chemical analysis.Electrochemical performance of the samples was tested in terms of charge-discharge capacity and cycling behavior.The results indicated that Fe(Ⅲ) impurity had obviously effect on the electrochemical properties of LiFePO4,and the formation of Fe 3+ was caused by the oxidation of Fe 2+ in the dissolving...  相似文献   

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Summary A -glucosidase (linamarase) was purified 52-fold with a recovery of 27% from the haemolymph of the larvae ofZygaena trifolii, ESPER, 1783 (Lepidoptera, Zygaenidae). The final enzyme preparation was found to be nearly homogeneous on both disc polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was determined to be about 130 kDa; it consisted of two subunits of about 66 kDa. The enzyme showed an optimum between pH 4.5 and 5 with linamarin and a broad optimum between pH 3.5 and 6.5 for p-nitrophenyl--D-glucoside; the temperature optimum was 40°C. The -glucosidase showed a high specificity for its endogenous substrates linamarin and lotaustralin. Among the other natural and artificial substrates tested, only prunasin and p-nitrophenyl--D-glucoside were hydrolyzed by the enzyme, whereas linustatin, salicin, cellobiose and trehalose were not. The enzyme is strongly inhibited by -glucosylpiperidine.  相似文献   

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Summary N-(5-Phosphopyridoxyl)-4-aminobutyric acid, a stable adduct of pyridoxal phosphate and 4-aminobutyric acid, has been shown to be a potent inhibitor of rat brain 4-aminobutyric acid aminotransferase (GABA-T) with a Ki of 1.4 M.Acknowledgments. This work was supported in part by the United Parkinson Foundation, l'Association Canadienne l'Ataxie de Friedreich, and the Medical Research Council of Canada.  相似文献   

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Scrutinizing the main activities of the Sociedad Astronómica de Barcelona (SAB), a scientific society that was founded in 1910 and lasted until 1921, this paper analyses how and why its members disseminated astronomy to society at large. Inspired by Camille Flammarion (1842–1925), and with a strong amateur character, the programme of the SAB raised interest among academic scientists, politicians, priests, navy officers, educated audiences, and positivist anticlerical writers. It rapidly conquered the public sphere through well-attended lectures, exhibitions, observations, and publications. In the context of an industrial city, which at that time was suffering serious social tensions, the popularization of astronomy transcended social and cultural boundaries. It created common ground between expert and lay knowledge, science and art, the ‘natural’ and the ‘social’, and between science and religion. In addition, it was considered as one of the only possible ways to raise the scientific level of a country such as Spain, which at that time perceived itself as peripheral, even backward, in terms of mainstream innovations in science and technology.  相似文献   

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Science Policy News

Portugal: Recent Information from the Department of International Relations of the Instituto Nacional de Investigação Cientifica, Lisboa (INIC)  相似文献   

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Summary Cyanidin-3--glucoside was shown to be an important factor of resistance in cottonGossypium hirsutum L. leaves to the tobacco budwormHeliothis virescens (Fab.). This provides a potential basis for achieving insect resistance in non-glanded cotton and other crops infested byHeliothis.In cooperation with the Mississippi Agriculture and Forestry Experiment Station, Mississippi State. Mention of a trademark, proprietary product or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable.  相似文献   

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C.F Gauss’s computational work in number theory attracted renewed interest in the twentieth century due to, on the one hand, the edition of Gauss’s Werke, and, on the other hand, the birth of the digital electronic computer. The involvement of the U.S. American mathematicians Derrick Henry Lehmer and Daniel Shanks with Gauss’s work is analysed, especially their continuation of work on topics as arccotangents, factors of n 2 + a 2, composition of binary quadratic forms. In general, this strand in Gauss’s reception is part of a more general phenomenon, i.e. the influence of the computer on mathematics and one of its effects, the reappraisal of mathematical exploration. I would like to thank the Alexander-von-Humboldt-Stiftung for funding this research. For their comments I would like to thank Catherine Goldstein, Norbert Schappacher and especially John Brillhart.  相似文献   

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As soon as he was appointed Minister of Public Instruction in 1863, Victor Duruy embarked on a major reform of French education. One of his most important initiatives was the creation of a new secondary curriculum (l'enseignement spécial) designed to prepare for careers in industry, trade, and agriculture. Edme Fremy, professor at the Muséum d'histoire naturelle, took the opportunity of proposing a course of instruction in practical chemistry that would be offered at the Muséum for young men intending to work in industry. Duruy approved the proposal, and funds were immediately made available. In contrast, Charles-Adolphe Wurtz, who led an internationally recognized research laboratory in organic chemistry in the Paris Faculty of Medicine, had difficulty in securing either administrative recognition or financial support. This article draws on the correspondence that Fremy and Wurtz exchanged with Duruy and senior officials in the Ministry between 1863 and 1869 to bring out the significance of the divergent ministerial responses to the two laboratories.  相似文献   

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