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E.J. Aiton M.Sc. Ph.D. 《Annals of science》2013,70(1):31-41
By the middle of the nineteenth century science was developing into a profession demanding advanced training and devotion to research. American institutions, however, were still better suited to an earlier stage of popular science. Many of the difficulties and frustrations for would-be scientists created by the time lag in institutional change are illustrated in the career of Cleveland Abbe. In the fifteen years between 1856 and 1871 his attempts to become an astronomer touched upon many significant aspects of American science as a profession, including the American observatory movement, the creation of graduate education, government support for science, and the tension between the joint goals of the increase and the diffusion of knowledge. 相似文献
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In 1793 Lord Macartney arrived in China as ambassador of King George III. The aims of his embassy were largely directed towards the enlargement of British trade with the far east, and especially with China. The embassy also had a diplomatic and cultural mission, to impress the Chinese with British achievements. They were to do so largely by distributing presents of British manufactures, chief among them being scientific instruments. The Chinese refused the embassy's requests, and clearly regarded the gifts of instruments as merely ingenious toys. This paper describes the role of instruments in the embassy, and contrasts British expectations with Chinese attitudes to scientific instruments. The embassy's failure is shown to reveal fundamental differences in British and Chinese eighteenth-century responses to science, and has wide cultural implications. 相似文献
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W. Fuller L. B. Tulloch M. J. Shattock S. C. Calaghan J. Howie K. J. Wypijewski 《Cellular and molecular life sciences : CMLS》2013,70(8):1357-1380
In cardiac muscle, the sarcolemmal sodium/potassium ATPase is the principal quantitative means of active transport at the myocyte cell surface, and its activity is essential for maintaining the trans-sarcolemmal sodium gradient that drives ion exchange and transport processes that are critical for cardiac function. The 72-residue phosphoprotein phospholemman regulates the sodium pump in the heart: unphosphorylated phospholemman inhibits the pump, and phospholemman phosphorylation increases pump activity. Phospholemman is subject to a remarkable plethora of post-translational modifications for such a small protein: the combination of three phosphorylation sites, two palmitoylation sites, and one glutathionylation site means that phospholemman integrates multiple signaling events to control the cardiac sodium pump. Since misregulation of cytosolic sodium contributes to contractile and metabolic dysfunction during cardiac failure, a complete understanding of the mechanisms that control the cardiac sodium pump is vital. This review explores our current understanding of these mechanisms. 相似文献
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J.M. Dubbey M.Sc. 《Annals of science》2013,70(1):37-48
In the history of chemistry, the Danish chemist Julius Thomsen (1826–1909) is best known for his contributions to thermochemistry. Throughout his life, he was a pronounced atomist and a tireless advocate of neo-Proutian views as to the constitution of matter. On many occasions, especially in his later years, he engaged in speculations concerning the unity of matter and the complexity of atoms. In this engagement, Thomsen was alone in Danish chemistry, but his works were representative of a large number of 19th-century chemists, particularly in England and Germany. Thomsen's ideas as to the constitution of matter, the periodic system and the noble gases, may be seen as typical of this vigorous trend in fin de siècle chemistry. 相似文献
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Jennifer J. Smith Volker Herzig Glenn F. King Paul F. Alewood 《Cellular and molecular life sciences : CMLS》2013,70(19):3665-3693
Pest insect species are a burden to humans as they destroy crops and serve as vectors for a wide range of diseases including malaria and dengue. Chemical insecticides are currently the dominant approach for combating these pests. However, the de-registration of key classes of chemical insecticides due to their perceived ecological and human health risks in combination with the development of insecticide resistance in many pest insect populations has created an urgent need for improved methods of insect pest control. The venoms of arthropod predators such as spiders and scorpions are a promising source of novel insecticidal peptides that often have different modes of action to extant chemical insecticides. These peptides have been optimized via a prey–predator arms race spanning hundreds of millions of years to target specific types of insect ion channels and receptors. Here we review the current literature on insecticidal venom peptides, with a particular focus on their structural and pharmacological diversity, and discuss their potential for deployment as insecticides. 相似文献