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181.
Renée van de Vall 《Foundations of Science》2013,18(1):169-172
My review of Ike Kamphof’s “Webcams to Save Nature: Online Space as Affective and Ethical Space” focuses on the question how the engagement of the spectator of the described websites is temporally structured and how the discrepancy between the instantaneity of affective response and the duration of moral engagement is solved. I propose to draw on Alexander Nehamas’ philosophy of beauty as an in-between, bringing affect and ethics closer together. 相似文献
182.
Massimiliano Sassoli de Bianchi 《Foundations of Science》2013,18(2):213-243
Founding our analysis on the Geneva-Brussels approach to the foundations of physics, we provide a clarification and classification of the key concept of observation. An entity can be observed with or without a scope. In the second case, the observation is a purely non-invasive discovery process; in the first case, it is a purely invasive process, which can involve either creation or destruction aspects. An entity can also be observed with or without a full control over the observational process. In the latter case, the observation can be described by a symmetry breaking mechanism, through which a specific deterministic observational process is selected among a number of potential ones, as explained in Aerts’ hidden measurement approach. This is what is called a product test, or product observation, whose consequences are that outcomes can only be predicted in probabilistic terms, as it is the case in typical quantum measurements. We also show that observations can be about intrinsic (stable) properties of the observed entity, or about relational (ephemeral) properties between the observer and observed entities; also, they can be about intermediate properties, neither purely classical, nor purely quantum. Our analysis allows us to propose a general conceptual characterization of quantum measurements, as observational processes involving three aspects: (1) product observations, (2) pure creation aspects and (3) ephemeral relational properties. We also discuss the important concept of non-spatiality and emphasize some of the differences and similarities between quantum and classical/relativistic observations. 相似文献
183.
Kemal de Soysa 《Studies in history and philosophy of science》2009,(4):421-430
An unusual silver celestial planisphere is held in the collection of the Whipple Museum of the History of Science (Wh.1762); little information about this object is recorded in the museum’s documentation. A comparison of this silver example with celestial planispheres printed on paper, coupled with the consideration of other aspects of the lives and work of the cartographers and instrument-makers involved in producing such objects, suggests some possibilities regarding its production. Through this individual case study, I aim to demonstrate that the careful examination of an individual instrument, coupled with an understanding of the class of instruments to which it belongs and the milieu in which it was produced, can result in a deeper understanding of any given artefact, its circumstances of design and manufacture, and its intended use and users. 相似文献
184.
重组葡激酶(r-Sak)工程菌发酵工艺的研究 总被引:2,自引:0,他引:2
通过对影响重组葡激酶表达的几个主要因素的研究,建立了较为适宜的发酵条件:接种量4%;初始pH7.2;在A600nm=2.5时加20%蔗糖诱导,诱导后4~5h收获,发酵液上清r-Sak含量可达到250mg/L以上,酶活力可达到6500RU/ml以上。 相似文献
185.
张文德 《贵州师范大学学报(社会科学版)》2001,(3):33-38
论述9至13世纪苏非主义在中亚形成和发展,阐述这一时期中亚苏非的主要思想及其与孙派信仰调和的过程以及苏非的精神功修,探讨了中亚苏非由松散的小团体演变成有严格规章制度的教团的三种宗教因素。 相似文献
186.
187.
Enhancement of LFA-1-mediated cell adhesion by triggering through CD2 or CD3 on T lymphocytes 总被引:61,自引:0,他引:61
Y van Kooyk P van de Wiel-van Kemenade P Weder T W Kuijpers C G Figdor 《Nature》1989,342(6251):811-813
The lymphocyte function-associated molecule LFA-1 (CD11a/CD18) plays a key part in lymphocyte adhesion. Lymphocytes do not adhere spontaneously; activation of protein kinase C (PKC) by phorbol esters, however, gives rise to strong LFA-1-dependent adhesion, indicating that activation of LFA-1 is required to induce cell adhesion. We have now investigated whether the functionally important CD2 and CD3 surface structures on T lymphocytes are involved in the activation of LFA-1. The stimulation of these molecules, which causes activation of PKC, strongly promoted LFA-1-dependent adhesion. Furthermore, we demonstrate by using cells from an LFA-1-deficient patient that this enhanced lymphocyte adhesion is caused by activation of the LFA-1 molecule and not by activation of its ligands. LFA-1 was persistently activated by triggering through CD2 but only transiently by triggering through CD3. We postulate that CD2 and CD3 can differentially regulate the affinity of LFA-1 for its ligands by modulating its molecular conformation through PKC-dependent mechanisms. 相似文献
188.
郭玉德 《科技情报开发与经济》2004,14(2):80-82
简要介绍了连续性缺口与非连续性缺口的概念及特征,阐述了缺口理论在证券投资技术分析中的指导意义,指出运用缺口理论指导投资操作是非常重要的一环,投资者可以利用缺口理论趋利避害:捕捉牛股、抛弃熊股,从而增加获利的概率。 相似文献
189.
张文德 《贵州师范大学学报(社会科学版)》2002,(2):68-71
明太祖即位不久,中亚帖木儿主动遣使来贡,明太祖采取了遣回撒马儿罕人,与之友好通商的政策,并接连派使臣回访,后来由于帖木儿扣留明使,并企图东侵中国,使双方关系处于不稳定状态。 相似文献
190.
桥梁智能CAD是计算机技术与桥梁设计知识高度综合的结果。规范知识的表达和推理是CAD系统的一个重要部分。在桥梁CAD系统中规范知识表达和应用将直接影响知识存储,推理机制和用户的接口形式。 相似文献