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161.
Wan-Bang Lo R. A. Jungmann J. S. Schweppe B. S. Berlin M. Grover 《Cellular and molecular life sciences : CMLS》1973,29(3):280-282
Zusammenfassung Das elektrophoretische Muster von Histonen und sauren Zellkernproteinen von Hühnerembryonen und deren primären und sekundären Fibroblastzellen wurde qualitativ und quantitativ verglichen. Die Zellkernproteine der verschiedenen Zelltypen erwiesen sich qualitativ als identisch, die relative quantitative Verteilung der Kernproteine war jedoch leicht verschieden. 相似文献
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163.
Organic–inorganic hybrid solar cells based on poly(3-hexylthiophene) and electrospun TiO2 nano bers were fabricated by solution process.The ef ciency of the device was improved by modifying CdS nanoparticles on the surface of TiO2 by electrochemical method.The CdS layer can lead to the increase of both open circuit voltage and short circuit current of the device,which are attributed to enhanced exciton dissociation and light absorption and suppressed carrier recombination by CdS at the heterojunction.However,too thick CdS layer led to increased series resistance and decreased ef ciency of the device.Therefore,the optimum condition of the CdS deposition was obtained,which increased the power conversion ef ciency of the device for about 50%.Our results indicate that the surface modi cation on the inorganic semiconductor layer is an effect way to improve the performance of the hybrid solar cells. 相似文献
164.
Yujing Gong Kung‐Cheng Ho Chia‐Chun Lo Andreas Karathanasopoulos I‐Ming Jiang 《Journal of forecasting》2019,38(4):354-373
This paper investigates the role of corporate social responsibility (CSR) performance in forecasting companys' stock prices and future returns. The forecasting analysis identifies a negative association between CSR performance and proxies of price delay. The negative CSR–delay association is weak for state‐owned enterprises (SOEs) because of their politically oriented motivation of CSR activities, but significantly strong for non‐SOEs. Furthermore, we find that forecasting delayed firms is expected to have higher future returns. In particular, the returns premium is most attributable to the CSR component of delay, compared with the non‐CSR component. Taken together, these results suggest that CSR performance plays a positive role in enhancing stock price efficiency, and a potential explanation is that CSR performance can be considered as additional information for equity predictions. 相似文献
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166.
Nobukazu Miyamoto Loc-Duyen D. Pham Ji Hae Seo Kyu-Won Kim Eng H. Lo Ken Arai 《Cellular and molecular life sciences : CMLS》2014,71(6):1055-1066
It is now relatively well accepted that the cerebrovascular system does not merely provide inert pipes for blood delivery to the brain. Cerebral endothelial cells may compose an embedded bunker of trophic factors that contribute to brain homeostasis and function. Recent findings suggest that soluble factors from cerebral endothelial cells nourish neighboring cells, such as neurons and astrocytes. Although data are strongest in supporting mechanisms of endothelial-neuron and/or endothelial-astrocyte trophic coupling, it is likely that similar interactions also exist between cerebral endothelial cells and oligodendrocyte lineage cells. In this mini-review, we summarize current advances in the field of endothelial-oligodendrocyte trophic coupling. These endothelial-oligodendrocyte interactions may comprise the oligovascular niche to maintain their cellular functions and sustain ongoing angiogenesis/oligodendrogenesis. Importantly, it should be noted that the cell–cell interactions are not static—the trophic coupling is disturbed under acute phase after brain injury, but would be recovered in the chronic phase to promote brain remodeling and repair. Oligodendrocyte lineage cells play critical roles in white matter function, and under pathological conditions, oligodendrocyte dysfunction lead to white matter damage. Therefore, a deeper understanding of the mechanisms of endothelial-oligodendrocyte trophic coupling may lead to new therapeutic approaches for white matter-related diseases, such as stroke or vascular dementia. 相似文献
167.
Alfred Nordmann 《Studies in history and philosophy of science》2012,43(1):38-46
Michael Friedman defines the scientific enterprise as an ongoing project with a dynamics of reason that persists through scientific revolutions: The coherence and continuity of science owes to a communicative rationality that is operative at all times. It assures us of our shared objective world by transforming subjective points of view into intersubjectively binding agreements. Though it takes a very broad approach epistemologically, this conception of science may yet be too narrow in respect to notions of objectivity. It excludes a prominent mode of knowledge production that might be called technoscientific. This exclusion becomes particularly evident in Friedman’s discussion of Heidegger as a critic of Cassirer and Carnap and as a critic of objectivity as “universal validity” of scientific propositions. If one tends to Heidegger’s own account of objectivity, one encounters a non-propositional notion of truth. Science is seen as a technology that brings forth phenomena and processes. Accordingly, even where modern physics appears to be concerned primarily with the formulation of theories and the testing of hypotheses, it uses mathematical and representational techniques to conceive and create the modern world. And more powerfully than intersubjective agreement, technologies assure us of the unity and objectivity of our simultaneously social as well as natural world. There may be good reasons to hold fast to the close affiliation of communicative rationality, science, and enlightenment. However, to the extent that it turns a blind eye to technoscientific knowledge production and the technological character of science, a philosophy of technoscience needs to develop an alternative perspective on questions of objectivity, explanation, inference, or validation. 相似文献