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1.
Stephen Kemp 《Studies in history and philosophy of science》2005,36(4):707-720
This article critically appraises David Bloor’s recent attempts to refute criticisms levelled at the Strong Programme’s social constructionist approach to scientific knowledge. Bloor has tried to argue, contrary to some critics, that the Strong Programme is not idealist in character, and it does not involve a challenge to the credibility of scientific knowledge. I argue that Bloor’s attempt to deflect the charge of idealism, which calls on the self-referential theory of social institutions, is partially successful. However, I suggest that although the Strong Programme should not be accused of ‘strong idealism’, it is still vulnerable to the criticism that it entails a form of ‘weak idealism’. The article moves on to argue that, contrary to Bloor, constructionist approaches do challenge the credibility of the scientific knowledge that they analyse. I conclude the article by arguing that sociological analyses of scientific knowledge can be conducted without the weak idealism and the credibility-challenging assumptions of the Strong Programme approach. 相似文献
2.
Budiansky S 《Nature》1983,301(5896):101
Joseph Cort, a researcher at Mount Sinai Medical School in New York City from 1976 to 1980, has admitted fabricating data on the synthesis of hormone analogues. Cort's research at Mount Sinai was supported principally by a contract from Vega Biochemicals, though he received a small amount of support under a National Institutes of Health grant to his department. 相似文献
3.
Budiansky S 《Nature》1983,304(5927):572
The Environmental Protection Agency is asserting regulatory control over the commercial production of genetically-engineered microorganisms, such as oil-eating bacteria, intended for release into the environment. EPA's legally-complex claim that such organisms are "new chemical substances," and thus subject to the Toxic Substances Control Act (TSCA), raises a challenge to the adequacy of regulation by the National Institute of Health's Recombinant DNA Advisory Committee (RAC) over the commercial and ecological implications of environmental release. Industry, which has been voluntarily adhering to the RAC guidelines, is reluctant to challenge application of the relatively lenient TSCA requirements but eager to see the legal uncertainties resolved. 相似文献
4.
Budiansky S 《Nature》1982,300(5888):95-96
An attorney for Stanford and the University of California has conceded that there is a serious error in the second Cohen-Boyer genetic engineering patent, but he argues that the patent is still valid. In an August decision to reject the patent, the U.S. Patent Office cited the error as one of several potential flaws. The same potential flaws are found in the original Cohen-Boyer patent, as well. Also in question is whether Robert Helling of the University of Michigan should be included as a co-inventor. Further appeals could delay a final decision until the summer of 1984 or beyond. 相似文献
5.
该文用完全线形分析法、磁化强度迁移法和自选锁定技术等三种具体的DNMR法对含有不同取代基的金属烯烃有机化合物中因碳碳键转动引起的分子内质子的化学交换的动力学行为进行了较为详细的研究。结果表明,测得的化学交换的速率常数是合理的。它们满足Eyring 和Ar-rehenuius 关系式;由此获得的化学交换的活化能参数和活化自由能的变化与化合物中的取代基的Hammett 常数6存在很好的一致关系。 相似文献
6.
7.
How People Use Rich Pictures to Help Them Think and Act 总被引:1,自引:1,他引:0
Groups of all kinds are complex organisations. To understand them and to facilitate them in process terms is a matter of rich and diverse discourse in varied fields from sustainable development to coastal ecology; from bandwidth in rural communities to health service provision. How to allow groups to discourse, problem solve and review their own issues and concerns? Diagrams in general and rich pictures in particular can be great means to allow groups to explore their subconscious, their occult sentiments and conflicted understandings. This paper explores and explains diverse use of pictures and shows how they can be applied and understood in group processes of all kinds. 相似文献
8.
Non-volcanic tremor driven by large transient shear stresses 总被引:2,自引:0,他引:2
Non-impulsive seismic radiation or 'tremor' has long been observed at volcanoes and more recently around subduction zones. Although the number of observations of non-volcanic tremor is steadily increasing, the causative mechanism remains unclear. Some have attributed non-volcanic tremor to the movement of fluids, while its coincidence with geodetically observed slow-slip events at regular intervals has led others to consider slip on the plate interface as its cause. Low-frequency earthquakes in Japan, which are believed to make up at least part of non-volcanic tremor, have focal mechanisms and locations that are consistent with tremor being generated by shear slip on the subduction interface. In Cascadia, however, tremor locations appear to be more distributed in depth than in Japan, making them harder to reconcile with a plate interface shear-slip model. Here we identify bursts of tremor that radiated from the Cascadia subduction zone near Vancouver Island, Canada, during the strongest shaking from the moment magnitude M(w) = 7.8, 2002 Denali, Alaska, earthquake. Tremor occurs when the Love wave displacements are to the southwest (the direction of plate convergence of the overriding plate), implying that the Love waves trigger the tremor. We show that these displacements correspond to shear stresses of approximately 40 kPa on the plate interface, which suggests that the effective stress on the plate interface is very low. These observations indicate that tremor and possibly slow slip can be instantaneously induced by shear stress increases on the subduction interface-effectively a frictional failure response to the driving stress. 相似文献
9.
Northen TR Yanes O Northen MT Marrinucci D Uritboonthai W Apon J Golledge SL Nordström A Siuzdak G 《Nature》2007,449(7165):1033-1036
The ability of mass spectrometry to generate intact biomolecular ions efficiently in the gas phase has led to its widespread application in metabolomics, proteomics, biological imaging, biomarker discovery and clinical assays (namely neonatal screens). Matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization have been at the forefront of these developments. However, matrix application complicates the use of MALDI for cellular, tissue, biofluid and microarray analysis and can limit the spatial resolution because of the matrix crystal size (typically more than 10 mum), sensitivity and detection of small compounds (less than 500 Da). Secondary-ion mass spectrometry has extremely high lateral resolution (100 nm) and has found biological applications although the energetic desorption/ionization is a limitation owing to molecular fragmentation. Here we introduce nanostructure-initiator mass spectrometry (NIMS), a tool for spatially defined mass analysis. NIMS uses 'initiator' molecules trapped in nanostructured surfaces or 'clathrates' to release and ionize intact molecules adsorbed on the surface. This surface responds to both ion and laser irradiation. The lateral resolution (ion-NIMS about 150 nm), sensitivity, matrix-free and reduced fragmentation of NIMS allows direct characterization of peptide microarrays, direct mass analysis of single cells, tissue imaging, and direct characterization of blood and urine. 相似文献
10.
Human CtIP promotes DNA end resection 总被引:3,自引:0,他引:3
Sartori AA Lukas C Coates J Mistrik M Fu S Bartek J Baer R Lukas J Jackson SP 《Nature》2007,450(7169):509-514
In the S and G2 phases of the cell cycle, DNA double-strand breaks (DSBs) are processed into single-stranded DNA, triggering ATR-dependent checkpoint signalling and DSB repair by homologous recombination. Previous work has implicated the MRE11 complex in such DSB-processing events. Here, we show that the human CtIP (RBBP8) protein confers resistance to DSB-inducing agents and is recruited to DSBs exclusively in the S and G2 cell-cycle phases. Moreover, we reveal that CtIP is required for DSB resection, and thereby for recruitment of replication protein A (RPA) and the protein kinase ATR to DSBs, and for the ensuing ATR activation. Furthermore, we establish that CtIP physically and functionally interacts with the MRE11 complex, and that both CtIP and MRE11 are required for efficient homologous recombination. Finally, we reveal that CtIP has sequence homology with Sae2, which is involved in MRE11-dependent DSB processing in yeast. These findings establish evolutionarily conserved roles for CtIP-like proteins in controlling DSB resection, checkpoint signalling and homologous recombination. 相似文献