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71.
In the collection of Watt's papers at Doldowlod, home of Lord Gibson-Watt, there are seven previously unpublished letters from James Hutton to James Watt, and four letters from Watt to Hutton, also unpublished. The letters were written between 1774 and 1795. Very little of Hutton's other correspondence survives, so these letters add significantly to our knowledge. The earliest letters, together with two letters to George Clerk-Maxwell (in the Scottish Record Office), describe geological tours that Hutton made through Wales, the Midlands, and the south-west of England in 1774. The correspondence after 1774, which will appear in a later edition of Annals of Science, reveals Watt's expertise in geology, and also discusses meteorology, varnish making, Symington's steam engines, the first experiments with steam navigation, pneumatic medicine, and other topics. 相似文献
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73.
Eric Schliesser 《Foundations of Science》2013,18(3):449-466
The first two sections of this paper investigate what Newton could have meant in a now famous passage from “De Graviatione” (hereafter “DeGrav”) that “space is as it were an emanative effect of God.” First it offers a careful examination of the four key passages within DeGrav that bear on this. The paper shows that the internal logic of Newton’s argument permits several interpretations. In doing so, the paper calls attention to a Spinozistic strain in Newton’s thought. Second it sketches four interpretive options: (i) one approach is generic neo-Platonic; (ii) another approach is associated with the Cambridge Platonist, Henry More; a variant on this (ii*) emphasizes that Newton mixes Platonist and Epicurean themes; (iii) a necessitarian approach; (iv) an approach connected with Bacon’s efforts to reformulate a useful notion of form and laws of nature. Hitherto only the second and third options have received scholarly attention in scholarship on DeGrav. The paper offers new arguments to treat Newtonian emanation as a species of Baconian formal causation as articulated, especially, in the first few aphorisms of part two of Bacon’s New Organon. If we treat Newtonian emanation as a species of formal causation then the necessitarian reading can be combined with most of the Platonist elements that others have discerned in DeGrav, especially Newton’s commitment to doctrines of different degrees of reality as well as the manner in which the first existing being ‘transfers’ its qualities to space (as a kind of causa-sui). This can clarify the conceptual relationship between space and its formal cause in Newton as well as Newton’s commitment to the spatial extended-ness of all existing beings. While the first two sections of this paper engage with existing scholarly controversies, in the final section the paper argues that the recent focus on emanation has obscured the importance of Newton’s very interesting claims about existence and measurement in “DeGrav”. The paper argues that according to Newton God and other entities have the same kind of quantities of existence; Newton is concerned with how measurement clarifies the way of being of entities. Newton is not claiming that measurement reveals all aspects of an entity. But if we measure something then it exists as a magnitude in space and as a magnitude in time. This is why in DeGrav Newton’s conception of existence really helps to “lay truer foundations of the mechanical sciences.” 相似文献
74.
From April to July 2008, we surveyed for breeding plovers at 32 sites in the semiarid highlands of Jalisco, Aguascalientes, Zacatecas, and San Luis Potosí, in the Central Mexican High Plateau. We documented evidence or presumption of breeding Snowy Plovers ( Charadrius alexandrinus ) at 3 sites, Killdeer ( C. vociferus ) at 15 sites, and Mountain Plovers ( C. montanus ) at 1 site. Our surveys showed that the region is important breeding ground for only the Killdeer. We documented an apparent breeding range extension of the Mountain Plover to slightly more than 200 km south of its previously known breeding range. 相似文献
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76.
We critically assess deep-seated assumptions and images of an information infrastructure, namely, that it needs to be uniform, tidy, and nonfragmented. This is necessary because our perception of order is socially constructed and, more importantly, because it has implications. Based on an historical reconstruction of the establishment of a Lotus Notes-based infrastructure in an internationally oriented oil company with 17,000 employees, we describe and analyze the productive role that appeals to an orderly infrastructure play. We trace its sources and describe how it operates. We also identify the implications in terms of choice of technological solution, delegation of organizational roles, and making organizational actors (in)visible. 相似文献
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78.
Kerkel K Spadola A Yuan E Kosek J Jiang L Hod E Li K Murty VV Schupf N Vilain E Morris M Haghighi F Tycko B 《Nature genetics》2008,40(7):904-908
Allele-specific DNA methylation (ASM) is a hallmark of imprinted genes, but ASM in the larger nonimprinted fraction of the genome is less well characterized. Using methylation-sensitive SNP analysis (MSNP), we surveyed the human genome at 50K and 250K resolution, identifying ASM as recurrent genotype call conversions from heterozygosity to homozygosity when genomic DNAs were predigested with the methylation-sensitive restriction enzyme HpaII. Using independent assays, we confirmed ASM at 16 SNP-tagged loci distributed across various chromosomes. At 12 of these loci (75%), the ASM tracked strongly with the sequence of adjacent SNPs. Further analysis showed allele-specific mRNA expression at two loci from this methylation-based screen--the vanin and CYP2A6-CYP2A7 gene clusters--both implicated in traits of medical importance. This recurrent phenomenon of sequence-dependent ASM has practical implications for mapping and interpreting associations of noncoding SNPs and haplotypes with human phenotypes. 相似文献
79.
Recent experience with several high-profile drugs demonstrates the great challenges in developing effective and safe therapeutics. A complementary approach to the popular paradigm of disease genetics is based on inherited factors that reduce the incidence and severity of disease among individuals who are genetically predisposed to disease. We propose testing specifically for modifier genes and protective alleles among at-risk individuals and studying the efficacy of therapeutics based on the genetics of health. 相似文献
80.
Robin Hendry has recently argued that although the term ‘element’ has traditionally been used in two different senses (basic substance and simple substance), there has nonetheless been a continuity of reference. The present article examines this author’s historical and philosophical claims and suggests that he has misdiagnosed the situation in several respects. In particular it is claimed that Hendry’s arguments for the nature of one particular element, oxygen, do not generalize to all elements as he implies. The second main objection is to Hendry’s view that the qua problem can be illuminated by appeal to the intention of scientists. 相似文献