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51.
This article examines the place of racial ideas in the constitution of political science as an academic discipline in the USA. For the Gilded Age generation that built the first PhD-granting departments in political science in the country, ‘race’ was the source of sovereignty, the basis of democratic legitimacy and a tool for delineating democracy's borders. It was also an important element of that cohort's aspiration to a ‘science’ of politics, distinct from what they viewed as the ‘abstract and formal’ theorizing of the eighteenth and early nineteenth centuries. Moreover, while the brand of racialism that characterized this founding moment came to seem outmoded within a few decades, in the 1920s political scientists seeking once again to claim an empirical, scientific basis for their discipline – and for American democracy – turned to new accounts and sciences of race.  相似文献   
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Ovarian maturity, egg development and brood size were analysed for three isolated populations (Madeira, the Canary Islands and Cape Verde Islands) of Plesionika edwardsii (Decapoda, Pandalidae) in the eastern Atlantic. Multiple colour patterns were observed at the same ovarian maturity stage, which was verified histologically, invalidating the extensive use of ovarian colour as a maturity stage criterion. The physiological size at sexual maturity, based on the maturity of the ovaries, was higher in Madeira (carapace length of 19.73?mm) and decreased to the Cape Verdes (16.39?mm). Synchronic ovarian maturation was observed during the embryo incubation process, and ovigerous females bearing embryos at the final stage of development were found throughout the year. Females are multiple spawners during the reproductive season, after which the reproductive process ends and a rest period begins. The absence of females larger than the size at sexual maturity with ovaries in Stage 1, the incubation of embryos in the final developmental stages, suggests that the resting period begins with a process that reabsorbs the energy located in the ovaries and that the resting period occurs asynchronously in females in each of the studied populations. Embryo size was independent of female body size in the three populations studied, but increased with the developmental stage. A power equation was used to describe the relationship between brood size and female body size in the three areas studied. The mean number of external Stage I embryos carried by females decreased from Madeira (n?=?7868) to the Cape Verdes (n?=?3781), where less energy, in terms of the number of embryos and the size of the eggs, was invested in reproduction. Although female size decreases from north to south, the egg number was higher in Madeira than in the Cape Verdes for the same size range.  相似文献   
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Microbially induced sedimentary structures (MISS) are an important facet of recent paleoichnological work because of their taphonomic implications. MISS are extensively studied in terms of their formation processes, recognition in the ancient record, and their diverse morphologies. Classification and terminology schemes are based on their appearance and mode of formation; however, the taxonomic treatment of MISS remains debated. Traditionally MISS have been considered sedimentary structures, and arguments have been made that they cannot be treated as trace fossils under the International Code of Zoological Nomenclature (ICZN) due to MISS being formed by communities of microbiota including algae, cyanobacteria, and others, rather than a single tracemaker. Here, we reexamine MISS using an ichnotaxonomic approach and apply ichnologic terminology and binomial names. Upon reexamining the holotype of Kinneyia Walcott, a genus commonly used to describe some MISS, we argue it cannot be used to correctly describe wrinkle or ripple-like features seen in MISS, and we agree with previous authors that Kinneyia is likely not biogenic in origin. We here assign a new ichnogenus and ichnospecies, Rugalichnus matthewii, to ripple-like sedimentary wrinkle marks known as MISS, separating them from the nomen dubium genus Kinneyia.  相似文献   
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The Dodo Raphus cucullatus, a giant flightless pigeon endemic to Mauritius, became extinct in the late seventeenth century, and so rapid was the birds’ disappearance, that by the beginning of the nineteenth century even its very existence was questioned. Only four specimens were then recorded in European museums, of which the most famous was the Tradescant or Oxford Dodo, now in the Oxford University Museum of Natural History. It comprised the head and one foot, and unique soft tissue in the form of skin and traces of feathers. The history of this specimen is reviewed, including the still unresolved question of how it came to Britain, and we provide evidence to show that it was stuffed but probably never mounted. The changes of ownership, and its cataloguing and curation in the different museums are also described, along with its varying roles in entertainment, education and research from the earliest years until the nineteenth century. This is part one of a two-part article; the second deals with the Tradescant Dodo from its dissection in the 1840s until the present day.  相似文献   
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Henry Charlton Bastian's support for spontaneous generation is shown to have developed from his commitment to the new evolutionary science of Darwin, Spencer, Huxley and Tyndall. Tracing Bastian's early career development shows that he was one of the most talented rising young stars among the Darwinians in the 1860s. His argument for a logically necessary link between evolution and spontaneous generation was widely believed among those sympathetic to Darwin's ideas. Spontaneous generation implied materialism to many, however, and it had associations in Britain with radical politics and amateur science. Huxley and the X Club were trying to create a public posture of Darwinism that kept it at arm's length from those negative associations. Thus, the conflict that developed when Huxley and the X Club opposed Bastian was at least as much about factional in-fighting among the Darwinians as it was about the experiments under dispute. Huxley's strategy to defeat Bastian and define his position as “non-Darwinian” contributed significantly to the shaping of Huxley's famous address “Biogenesis and Abiogenesis.” Rhetorically separating Darwinism from Bastian was thus responsible for Huxley's first clear public statement that a naturalistic origin of life was compatible with Darwin's ideas, but only in the earth's distant past. The final separation of the discourse on the meaning of Brownian movement and “active molecules” from any possible link with spontaneous generation also grew out of Huxley's strategy to defeat Bastian. Clashes between Bastian and the X Club are described at the BAAS, the Royal Society, and in the pages of Nature and other journals. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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This minireview traces the photosynthesis genes, their structure, function and expression in Rhodobacter sphaeroides 2.4.1, as applied to our understanding of the inducible photosynthetic intracytoplasmic membrane system or ICM. This focus has represented the research interests of this laboratory from the late 1960s to the present. This opportunity has been used to highlight the contributions of students and postdoctorals to this research effort. The work described here took place in a much greater and much broader context than what can be conveyed here. The ‘timeline’ begins with a clear acknowledgment of the work of June Lascelles and William Sistrom, whose foresight intuitively recognized the necessity of a ‘genetic’ approach to the study of photosynthesis in R. sphaeroides. The ‘timeline’ concludes with the completed genome sequence of R. sphaeroides 2.4.1. However, it is hoped the reader will recognize this event as not just a new beginning, but also as another hallmark describing this continuum. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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中国传统道家生态智慧从哲学层面建立了人地关系的至高至善的标准,对从根源指导生态规划设计具有重要价值。在西方科学理性和技术理性的背景下,约翰·莱尔提出了“道家方式是人文生态系统设计的正确方式”的观点,并认为伊恩·麦克哈格设计的伍德兰兹社区正是西方人充分借鉴吸收道家智慧和道家方式的集中体现。从土地利用与空间布局、自然排水系统、调蓄机制和后期管理4部分探讨伍德兰兹社区现代生态适宜性分析技术与传统道家生态思想的契合,并探索道家思想与现代生态规划设计思想的融合的特征与规律,为生态规划设计提供一种具有创造性实践意义的新思路。  相似文献   
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