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1.
Since he proved his theorem in 1982, Fine has been challenging the traditional interpretation of the experimental violation of the Bell Inequalities (BI). A natural interpretation of Fine's theorem is that it provides us with an alternative set of assumptions on which to place blame for the failure of the BI, and opens to a new interpretation of the violation of the BI. Fine has a stronger interpretation for his theorem. He claims that his result undermines the traditional interpretation in terms of local realism. The aim of this paper is to understand and to assess Fine's claim. We distinguish three different strategies that Fine uses in order to support his view. We show that none of these strategies is successful. Fine fails to prove that local realism is not at stake in the violation of the BI by quantum phenomena.  相似文献   

2.
韩国利用外商R&D投资的经验及启示   总被引:5,自引:0,他引:5  
韩国在利用外商研发投资中存在诸多值得我们借鉴的地方,如鼓励本国企业与跨国公司研发机构合作、着力增强本国企业的技术吸收消化能力、为本国企业与跨国公司搭建合作平台、合理引导跨国公司的研发投资活动、鼓励本国企业到海外建立研发机构等。我国在利用外商研发投资过程中,应积极借鉴韩国经验,大力优化人才培养与任用机制、健全和完善知识产权保护的法律体系、保护生态环境、优化和完善服务环境、加强本土企业R&D能力培养。  相似文献   

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We call attention to the historical fact that the meaning of symmetry in antiquity—as it appears in Vitruvius’s De architectura—is entirely different from the modern concept. This leads us to the question, what is the evidence for the changes in the meaning of the term symmetry, and what were the different meanings attached to it? We show that the meaning of the term in an aesthetic sense gradually shifted in the context of architecture before the image of the balance was attached to the term in the middle of the 18th century and well before the first modern scientific usage by Legendre in 1794.  相似文献   

5.
The endothelium provides a strong barrier separating circulating blood from tissue. It also provides a significant challenge for immune cells in the bloodstream to access potential sites of infection. To mount an effective immune response, leukocytes traverse the endothelial layer in a process known as transendothelial migration. Decades of work have allowed dissection of the mechanisms through which immune cells gain access into peripheral tissues, and subsequently to inflammatory foci. However, an often under-appreciated or potentially ignored question is whether transmigrated leukocytes can leave these inflammatory sites, and perhaps even return across the endothelium and re-enter circulation. Although evidence has existed to support “reverse” transendothelial migration for a number of years, it is only recently that mechanisms associated with this process have been described. Here we review the evidence that supports both reverse transendothelial migration and reverse interstitial migration within tissues, with particular emphasis on some of the more recent studies that finally hint at potential mechanisms. Additionally, we postulate the biological significance of retrograde migration, and whether it serves as an additional mechanism to limit pathology, or provides a basis for the dissemination of systemic inflammation.  相似文献   

6.
A decrease in the levels of the desmosomal plaque protein, plakophilin3 (PKP3), leads to a decrease in desmosome size and cell-cell adhesion. To test the hypothesis that PKP3 is required for desmosome formation, the recruitment of desmosomal components to the cell surface was studied in the PKP3 knockdown clones. The PKP3 knockdown clones showed decreased cell border staining for multiple desmosomal proteins, when compared to vector controls, and did not form desmosomes in a calcium switch assay. Further analysis demonstrated that PKP3, plakoglobin (PG) and E-cadherin are present at the cell border at low concentrations of calcium. Loss of either PG or E-cadherin led to a decrease in the levels of PKP3 and other desmosomal proteins at the cell border. The results reported here are consistent with the model that PG and E-cadherin recruit PKP3 to the cell border to initiate desmosome formation.  相似文献   

7.
The use of metabolomics to dissect plant responses to abiotic stresses   总被引:1,自引:0,他引:1  
Plant metabolism is perturbed by various abiotic stresses. As such the metabolic network of plants must be reconfigured under stress conditions in order to allow both the maintenance of metabolic homeostasis and the production of compounds that ameliorate the stress. The recent development and adoption of metabolomics and systems biology approaches enable us not only to gain a comprehensive overview, but also a detailed analysis of crucial components of the plant metabolic response to abiotic stresses. In this review we introduce the analytical methods used for plant metabolomics and describe their use in studies related to the metabolic response to water, temperature, light, nutrient limitation, ion and oxidative stresses. Both similarity and specificity of the metabolic responses against diverse abiotic stress are evaluated using data available in the literature. Classically discussed stress compounds such as proline, γ-amino butyrate and polyamines are reviewed, and the widespread importance of branched chain amino acid metabolism under stress condition is discussed. Finally, where possible, mechanistic insights into metabolic regulatory processes are discussed.  相似文献   

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A strong version of scientism, such as that of Alex Rosenberg, says, roughly, that natural science reliably delivers rational belief or knowledge, whereas common sense sources of belief, such as moral intuition, memory, and introspection, do not. In this paper I discuss ten reasons that adherents of scientism have or might put forward in defence of scientism. The aim is to show which considerations could plausibly count in favour of scientism and what this implies for the way scientism ought to be formulated. I argue that only three out of these ten reasons potentially hold water and that the evidential weight is, therefore, on their shoulders. These three reasons for embracing scientism are, respectively, particular empirical arguments to the effect that there are good debunking explanations for certain common sense beliefs, that there are incoherences and biases in the doxastic outputs of certain common sense sources of belief, and that beliefs that issue from certain common sense doxastic sources are illusory. From what I argue, it follows that only a version of scientism that is significantly weaker than many versions of scientism that we find in the literature is potentially tenable. I conclude the paper by stating what such a significantly weaker version of scientism could amount to.  相似文献   

10.
Mononuclear phagocytes in distinct differentiation stages and cultured under different conditions were tested for their sensitivity towards lipopolysaccharide (LPS), using procoagulant activity (PCA) expression and tumor necrosis factor (TNF) production as indices. The response of mature monocyte-derived macrophages differed from that of freshly isolated monocytes 1) by higher levels of constititive PCA, 2) by responding to approximately 1,000-fold lower concentrations of LPS with PCA and TNF production, and 3) by a faster rise in PCA and TNF production. Due to the high constitutive level of PCA expression, the PCA stimulation index for LPS was low in macrophages when compared with that in monocytes. Thus, during differentiation to macrophages, human monocytes acquire increased sensitivity to LPS (2 orders of magnitude more sensitive than a sensitive turbidimetricLimulus amoebocyte lysate assay). This exquisite sensitivity to LPS is expressed regardless of whether LPS is offered in the presence or absence of lipopolysaccharide binding protein-containing serum. This points to as yet uncharacterized pathways of high affinity interaction between LPS and macrophages.  相似文献   

11.
Summary Through their catalytic abilities microbes can increase rates of chemical reactions which would take a very long time to reach equilibrium under abiotic conditions. Microbes also alter the concentration and composition of chemicals in the environment, thereby creating new conditions for further biological and chemical reactions. Rates of degradation and possible indirect consequences on leaching rates in waste repositories are a function of the presence or absence of microbes and of the conditions which allow them to become catalytically active.Microbially mediated reactions are no exception to the rule that all chemical processes are basically governed by thermodynamic laws. Naturally occurring processes proceed in the direction that leads to the minimal potential energy level attained when equilibrium is reached. A continuous supply of energy to an ecosystem in the form of biochemically unstable compounds maintains non-equilibrium conditions, a prerequisite for all chemotrophic life. Energy is released as a chemical reaction progresses towards equilibrium. Microbes scavenge that portion of the free energy of reaction (Gr) which can be converted into biochemically usable forms during the chemical oxidation processes. As electrontransfer catalysts, the microorganisms mediate reactions which are thermodynamically possible thereby stimulating reaction rates. Decomposition and mineralization in systems without a continuous supply of substrates and oxidants will lead to equilibria with minimal free energy levels at which point further microbial action would cease. The differences in the free energy levels of reactions (Gr), represent the maximal energy which is available to microorganisms for maintenance and growth. How much of the released free energy will be conserved in energy-rich bonds, compounds (e.g. ATP), and chemical potentials (e.g. emf) useful for biosynthesis and biological work is characteristic for the microbes involved and the processes and metabolic routes employed.Materials whose elements are not present in the most oxidized form attainable in the oxic environment of our planet are potentially reactive. Microbial activities are associated only with chemical reactions whose free energy changes are exergonic. This should be kept in mind for all investigations related to the role of microbes in repositories or in the layout of proper waste storage conditions. Rigorous application of thermodynamic concepts to environmental microbiology allows one to develop models and design experiments which are often difficult to conceive of in complex natural systems from physiological information alone. Thermodynamic considerations also aid in selecting proper deposition conditions and in carrying out thoughtful experiments in areas related to microbial ecology of waste repositories.  相似文献   

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Summary Electrophysiological recordings from freely behaving rats, previously implanted stereotaxically with permanent electrodes in the pineal, ventromedial hypothalamus, caudate nucleus, lateral geniculate body and medial geniculate body were obtained. The pineal photic responses revealed 5 sequential components. Injection of a neuronal blocker at the level of the superior cervical ganglion did not alter the earlier photic responses, but did eliminate the late components (N2–P3) for 60–90 min after the injection. All of the other responses were unchanged during the experiment. The present experiments demonstrated that photic input travels to the pineal through two pathways.The author is grateful to Dr C.M. Prashad and Ms. Marjorie Brown for technical assistance. Supported in part by grant NS 16596.  相似文献   

14.
In this paper, I raise some worries with John D. Norton's application of his material theory of induction to the study of analogical inferences. Skeptical that these worries can be properly addressed, I propose a principle to guide the philosophical research on analogical inferences and argue for its usefulness.  相似文献   

15.
Is there a common model inherent in macroeconomic data? Macroeconomic theory suggests that market economies of various nations should share many similar dynamic patterns; as a result, individual country empirical models, for a wide variety of countries, often include the same variables. Yet, empirical studies often find important roles for idiosyncratic shocks in the differing macroeconomic performance of countries. We use forecasting criteria to examine the macrodynamic behaviour of 15 OECD countries in terms of a small set of familiar, widely used core economic variables, omitting country‐specific shocks. We find this small set of variables and a simple VAR ‘common model’ strongly support the hypothesis that many industrialized nations have similar macroeconomic dynamics. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

16.
Summary A mutant ofAspergillus nidulans resistant to ethidium bromide was isolated and the semi-dominant gene responsible for this resistance was allocated on linkage group II at 17.42±3.05 units of recombination from thewA3 gene. The gene also confers cross-resistance to acriflavin, malachite green and crystal violet. It was also shown that riboflavin is antagonistic to the toxic effect of ethidium bromide, at certain concentrations. The mechanisms which could be responsible for the toxic effect of this drug are discussed and compared with those of acriflavin. The use of theEtb 1 gene in genetical analysis through the parasexual cycle is suggested.Acknowledgements. The authors are thankful to the National Council for the Development of Science and Technology (CNPq) for financial support through PIG-SIP 04/053 FAPESP.  相似文献   

17.
Hypertensive renal disease occurs at increased frequency among the relatives of patients with this disease compared to individuals who lack a family history of disease. This suggests a heritable risk in which genetic variation may play a role. These observations have motivated a search for genetic variation contributing to this risk in both experimental animal models and in human populations. Studies of animal models indicate the capacity of natural genetic variants to contribute to disease risk and have produced a few insights into the disease mechanism. In its current phase, human population genetic studies have sought to associate genetic variation with disease in large populations by testing genotypes at a large number of common genetic variations in the genome, expecting that common genetic variants contributing to renal disease risk will be identified. These genome-wide association studies (GWAS) have been productive and are a clear technical success; they have also identified narrowly defined loci and genes containing variation contributing to disease risk. Further extension and refinement of these GWAS are likely to extend this success. However, it is also clear that few additional variants with substantial effects accounting for the greatest part of heritability will be uncovered by GWAS. This raises an interesting biological question regarding where the remaining unaccounted heritable risk may be located. At present, much consideration is being given to this question and to the challenge of testing hypotheses that lead from the various alternative mechanisms under consideration. One result of the progress of GWAS is likely to be a renewed interest in mechanisms by which related individuals can share and transmit traits independently of Mendelian inheritance. This paper reviews the current progress in this area and considers other mechanisms by which familial aggregation of risk for renal disease may arise.  相似文献   

18.
Philosophers of science continue to elaborate our understanding of the roles that values play in scientific reasoning, practice, and institutions. This special issue focuses on the environmental sciences, a mosaic of fields ranging from restoration ecology to forestry to climatology, unified by its attention to the relationships between humans and their habitats. It is a field that revolves around ameliorating environmental problems, aiming to support the provision of social goods and provide guidance to policymakers about how to regulate individuals and industries. Values abound in such judgments as setting the boundaries of an ecosystem, integrating the human dimensions of social-ecological systems, and collaborating with stakeholders. Since few in the field are likely to insist that these judgments can be made without reference to social values, environmental science can serve as fertile ground for exploring the ethical, social, and political terrain at the frontier of the science and values discourse.  相似文献   

19.
本文简要论述了我国建筑市场将面临的新的发展机遇,分析了我国加入世界贸易组织后对建筑业的有利与不利因素,讨论了我国建筑业进入国际市场的前景,建议了应对策略和政府的政策导向。  相似文献   

20.
The concept of interactional expertise – characterized by sociologists Harry Collins and Robert Evans as the ability to speak the language of a discipline without the corresponding ability to practice – can serve as a powerful way of breaking down expert/non-expert dichotomies and providing a role for new voices in specialist communities. However, in spite of the vast uptake of this concept and its potential to fruitfully address many important issues related to scientific expertise, there has been surprisingly little critical analysis of it. We seek to remedy this situation by considering potential benefits of interactional expertise and the ways in which the current conception can – and cannot – realize those benefits. In particular, we argue that interactional expertise hasn't reached its full potential for addressing who ought to be involved in scientific research and decision-making, largely owing to an unnecessarily restrictive way of operationalizing the concept. In its place, we offer a broader, more pluralistic account of interactional expertise – one that is in line with the original spirit of the concept, but also captures the diversity that we see as being an important aspect of interactional experts and the value they can bring to the table.  相似文献   

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