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1.
Brian Young 《Studies in history and philosophy of science》2004,35(3):645-663
The career of John Jackson (1686-1763), Arian theologian and controversialist, provides a key to unlocking the early reception and quick collapse of a Newtonian natural apologetic originally developed by Samuel Clarke. The importance of friendship and discipleship in eighteenth-century intellectual enquiry is emphasised, and the links between Newton and his followers are traced alongside those of a group of Cambridge Lockeans, led by Jackson’s direct contemporary Daniel Waterland, who proved instrumental in the initial dismantling of Clarke’s brand of Newtonian apologetic. The controversial context of this engagement is shown to have been largely provided by the religiously compromising rise of freethinking, and Tindal’s Christianity as old as the creation (1731) signalled the dangers to proponents of natural religion as an adjunct of Christian apologetic in such a heated atmosphere. Religious division of the sort that resulted paradoxically played into the hands of the freethinkers in the anticlerical atmosphere of the 1730s, and accusations were exchanged between Newtonians and Lockeans accordingly. The dynamic of England’s Enlightenment experience is, then, a complicated one, and, as the career and writings of Jackson and William Whiston demonstrate, it was one which absorbed as well as repudiated ‘enthusiasm’. 相似文献
2.
Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa tic transfer equipments. This paper proposes a new approach for the shape design and manufacturing of the cylindrical cam. The design approach uses the relative velocity concept and the manufacturing approach uses the inverse kinematics concept. For the shape desig n, the contact points betw... 相似文献
3.
High-frequency generalised transduction by bacteriophage T4 总被引:30,自引:0,他引:30
4.
Jinwon Lim Hyo-Jung Lee Bonglee Kim Jeong-Un Choi Yoeok Shin Eun Jung Sohn Sung-Hoon Kim 《科学通报(英文版)》2014,59(25):3127-3133
Though Hongbaekjeong(HBJ),a hebal mixture of three medicinal plants,has been traditionally used for arthritis and muscular pain,its scientific evidence still remains unclear.Thus,in the present study,analgesic and anti-inflammatory mechanism of HBJ was evaluated in vitro and in vivo.HBJ significantly reduced NO production and prostaglandin E2(PGE2)release and also attenuated the expression of cyclooxygenase 2(COX-2)in lipopolysaccharides(LPS)and interferon(IFN)-c treated RAW 264.7 cells.Furthermore,HBJ abrogated the production of proinflammatory cytokines such as interleukin(IL)1b,IL-6,IL-8 and monocyte chemoattractant protein-1(MCP-1)in LPS and IFN-c treated RAW 264.7 cells.In addition,HBJ significantly decreased the number of writhing syndrome induced by acetic acid,and also increased latency in hot-plate method and tail flick test in mice.Consistently,HBJ significantly reduced the edema volume in the hind paw of the rats with arthritis induced by Freund’s complete adjuvant(FCA)compared to untreated control.Collectively,our findings demonstrate the antiinflammatory and analgesic potential of HBJ via inhibition of proinflammatory cytokines and PGE2 release for treatment of arthritis and muscular pain. 相似文献
5.
The motion of domain walls is critical to many applications involving ferroelectric materials, such as fast high-density non-volatile random access memory. In memories of this sort, storing a data bit means increasing the size of one polar region at the expense of another, and hence the movement of a domain wall separating these regions. Experimental measurements of domain growth rates in the well-established ferroelectrics PbTiO3 and BaTiO3 have been performed, but the development of new materials has been hampered by a lack of microscopic understanding of how domain walls move. Despite some success in interpreting domain-wall motion in terms of classical nucleation and growth models, these models were formulated without insight from first-principles-based calculations, and they portray a picture of a large, triangular nucleus that leads to unrealistically large depolarization and nucleation energies. Here we use atomistic molecular dynamics and coarse-grained Monte Carlo simulations to analyse these processes, and demonstrate that the prevailing models are incorrect. Our multi-scale simulations reproduce experimental domain growth rates in PbTiO3 and reveal small, square critical nuclei with a diffuse interface. A simple analytic model is also proposed, relating bulk polarization and gradient energies to wall nucleation and growth, and thus rationalizing all experimental rate measurements in PbTiO3 and BaTiO3. 相似文献
6.
Identification of the transforming EML4-ALK fusion gene in non-small-cell lung cancer 总被引:1,自引:0,他引:1
7.
8.
Kasahara M Naruse K Sasaki S Nakatani Y Qu W Ahsan B Yamada T Nagayasu Y Doi K Kasai Y Jindo T Kobayashi D Shimada A Toyoda A Kuroki Y Fujiyama A Sasaki T Shimizu A Asakawa S Shimizu N Hashimoto S Yang J Lee Y Matsushima K Sugano S Sakaizumi M Narita T Ohishi K Haga S Ohta F Nomoto H Nogata K Morishita T Endo T Shin-I T Takeda H Morishita S Kohara Y 《Nature》2007,447(7145):714-719
Teleosts comprise more than half of all vertebrate species and have adapted to a variety of marine and freshwater habitats. Their genome evolution and diversification are important subjects for the understanding of vertebrate evolution. Although draft genome sequences of two pufferfishes have been published, analysis of more fish genomes is desirable. Here we report a high-quality draft genome sequence of a small egg-laying freshwater teleost, medaka (Oryzias latipes). Medaka is native to East Asia and an excellent model system for a wide range of biology, including ecotoxicology, carcinogenesis, sex determination and developmental genetics. In the assembled medaka genome (700 megabases), which is less than half of the zebrafish genome, we predicted 20,141 genes, including approximately 2,900 new genes, using 5'-end serial analysis of gene expression tag information. We found single nucleotide polymorphisms (SNPs) at an average rate of 3.42% between the two inbred strains derived from two regional populations; this is the highest SNP rate seen in any vertebrate species. Analyses based on the dense SNP information show a strict genetic separation of 4 million years (Myr) between the two populations, and suggest that differential selective pressures acted on specific gene categories. Four-way comparisons with the human, pufferfish (Tetraodon), zebrafish and medaka genomes revealed that eight major interchromosomal rearrangements took place in a remarkably short period of approximately 50 Myr after the whole-genome duplication event in the teleost ancestor and afterwards, intriguingly, the medaka genome preserved its ancestral karyotype for more than 300 Myr. 相似文献
9.
Young DA Wright AP Roberts JL Warner RC Young NW Greenbaum JS Schroeder DM Holt JW Sugden DE Blankenship DD van Ommen TD Siegert MJ 《Nature》2011,474(7349):72-75
The first Cenozoic ice sheets initiated in Antarctica from the Gamburtsev Subglacial Mountains and other highlands as a result of rapid global cooling ~34 million years ago. In the subsequent 20 million years, at a time of declining atmospheric carbon dioxide concentrations and an evolving Antarctic circumpolar current, sedimentary sequence interpretation and numerical modelling suggest that cyclical periods of ice-sheet expansion to the continental margin, followed by retreat to the subglacial highlands, occurred up to thirty times. These fluctuations were paced by orbital changes and were a major influence on global sea levels. Ice-sheet models show that the nature of such oscillations is critically dependent on the pattern and extent of Antarctic topographic lowlands. Here we show that the basal topography of the Aurora Subglacial Basin of East Antarctica, at present overlain by 2-4.5?km of ice, is characterized by a series of well-defined topographic channels within a mountain block landscape. The identification of this fjord landscape, based on new data from ice-penetrating radar, provides an improved understanding of the topography of the Aurora Subglacial Basin and its surroundings, and reveals a complex surface sculpted by a succession of ice-sheet configurations substantially different from today's. At different stages during its fluctuations, the edge of the East Antarctic Ice Sheet lay pinned along the margins of the Aurora Subglacial Basin, the upland boundaries of which are currently above sea level and the deepest parts of which are more than 1?km below sea level. Although the timing of the channel incision remains uncertain, our results suggest that the fjord landscape was carved by at least two iceflow regimes of different scales and directions, each of which would have over-deepened existing topographic depressions, reversing valley floor slopes. 相似文献
10.