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11.
The societal impacts of nanotechnology have attracted growing attention in the United States and Europe in recent years. In Japan, the National Institute of Advanced Industrial Science and Technology (Technology Information Department) has played a central role in promoting discussions on this topic by collecting information from Japan and overseas, creating a network of the interested parties, and providing a forum for discussion. This paper presents a summary of recent activities in Japan relating to the societal impacts of nanotechnology, fro the launch of the “Nanotechnology and Society” open forum (August 2004) until the “Nanotechnology Debate” discussion forum (February 2007), and outlines the policy recommendations that came out of a project entitled “Research on Facilitation of Public Acceptance of Nanotechnology” (March 2006).  相似文献   
12.
Nanomaterials and their associated technologies hold promising opportunities for the development of new materials and applications in a wide variety of disciplines, including medicine, environmental remediation, waste treatment, and energy conservation. However, current information regarding the environmental effects and health risks associated with nanomaterials is limited and sometimes contradictory. This article summarizes the conclusions of a 2008 NATO workshop designed to evaluate the wide-scale implications (e.g., benefits, risks, and costs) of the use of nanomaterials on human health and the environment. A unique feature of this workshop was its interdisciplinary nature and focus on the practical needs of policy decision makers. Workshop presentations and discussion panels were structured along four main themes: technology and benefits, human health risk, environmental risk, and policy implications. Four corresponding working groups (WGs) were formed to develop detailed summaries of the state-of-the-science in their respective areas and to discuss emerging gaps and research needs. The WGs identified gaps between the rapid advances in the types and applications of nanomaterials and the slower pace of human health and environmental risk science, along with strategies to reduce the uncertainties associated with calculating these risks.  相似文献   
13.
Conditions are presented for the existence of increasing and Lipschitz continuous maximizers in a general one-stage optimization problem. This property results in substantial numerical savings in case of a discrete parameter space. The one-stage result and properties of concave functions lead to simple conditions for the existence of optimal policies, composed of increasing and Lipschitz continuous decision rules, for several dynamic programs with discrete state and action space, in which case discrete concavity plays a dominant role. One of the examples, a general multi-stage allocation problem, is considered in detail. Finally, some known results in the case of a continuous state and action space are generalized.  相似文献   
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15.
The interactions of 2-nitroaniline (2-NA), 3-nitroaniline (3-NA) and 4-nitroaniline (4-NA) with bovine serum albumin (BSA) have been investigated by means of fluorescence spectrometry, synchronous fluorescence spectrometry and UV absorption spectrometry under the simulative physiological conditions. Association constants (K A ) were estimated by the remarkable static quenching effect of 2-NA, 3-NA and 4-NA to the intrinsic fluorescence of BSA, and thermodynamic parameters such as enthalpy change (ΔH) and entropy change (ΔS) were calculated according to van’t Hoff equation. The results show that hydrophobic force plays a main role in the interaction of nitroanilines to BSA, nitroanilines have high affinity to BSA and the affinity order is as follows: 4-NA?>?2-NA?>?3-NA. On the basis of this study, it is found that percents of the binding of nitroanilines to BSA are almost no relative to the concentrations of nitroanilines, and correlation between K A and logK ow is disclosed. In the meantime, relationships between the combination of nitroanilines with BSA and toxicological implications were also discussed. In addition, synchronous fluorescence method was used to study the interaction mechanisms between nitroanilines and BSA, and energy transfer distances from BSA to nitroanilines were estimated based on the Förster’s non-radiation energy transfer theory. The results suggest that the binding site for nitroanilines on BSA is close to the sub-domain IIA where Trp 214 is located.  相似文献   
16.
重叠函数是一类特殊的非结合的二元聚类函数.利用重叠函数可以诱导出不同形式的模糊蕴涵.文[7]介绍了由重叠函数O和模糊否定N诱导出的模糊蕴涵—(O,N)-蕴涵,并对(O,N)-蕴涵的基本性质进行了研究,但尚存一些重要性质尚未得到研究.主要基于自同构φ和模糊否定N的相关性质对(O,N)-蕴涵进行深入研究,给出(O,N)-蕴...  相似文献   
17.
After an introduction of the theoretical framework and concepts of transition studies, this article gives an overview of how structural change in social systems has been studied from various disciplinary perspectives. This overview first leads to the conclusion that computational and mathematical approaches and their practical form, modeling, up till now, have been almost absent in the research and theorizing of structural change or transitions in social systems. Second, this review of the social science literature suggests numerous theoretical constructs relevant for transition modeling. Relevant concepts include the conceptualization of the micro-to-macro link, the importance of explaining both stability and change, quantitative and qualitative definitions of structural change, the use of dichotomies, synchronic and diachronic reasoning in explaining structural change, definitions of basic patterns of social change, the conceptualization of resistance to change and intentional and normative aspects of social change. This article employs these theoretical concepts to describe and discuss the models presented in this special issue in order to develop an understanding of what exactly entails a computational or mathematical approach to societal transitions.
Flaminio SquazzoniEmail: URL: http://www.unibs.it/on-line/dss/Home/Personale/PersonaleDocente/articolo1758.html
  相似文献   
18.
Volatile organic compounds (VOCs) play a major role in the physical and chemical process of the tropospheric chemical reactions in both polluted and remote environments. A theoretical work has been presented on the VOC of allyl alcohol with O3 molecule is investigated using density functional theory methods. The reaction profile is initiated through the cycloaddition of ozone which leads to the formation of primary ozonide with minimal relative energy barrier of 1.31 kcal/mol which decomposes to form carbonyl molecule and carbonyl oxide. Carbonyl oxide, i.e. criegee intermediates reacts with various atmospheric species to produce more hazardous and toxic end products to the environment. The condensed form of Fukui function was calculated to predict reactive sites of the primary and secondary reaction profile. The rate coefficient using CVT with SCT over the temperature range of 258–358K is analysed and also to study the atmospheric effects of allyl alcohol in the atmosphere. The predicted rate coefficient for the favourable reaction pathway of kp1 found to be 1.190 ×10?15 cm3/molecule/sec and comparable with the experimental result at 298 K. The atmospheric lifetime of allyl alcohol was found to be around 10 hours in addition to that global warming potentials are compared with the CO2.  相似文献   
19.
A multidimensional version of the Li–Yorke cycle coexisting theorem [Li, T.-Y. and Yorke, J.A. “Period three implies chaos”, Am. Math. Monthly, 82, 985–992] is established for certain (e.g. expansive) maps. The related fixed- and periodic-point theorems are developed in R n . Implications of 3-orbits are discussed.  相似文献   
20.
A January 2005 telephone survey of 1200 people in the U.S. and 2000 Canadians provides a snapshot of current North American opinion regarding nanotechnology at this crucial early point in its emergence from the laboratory to the arena of public discourse and public understanding. Using a typology of “publics” developed through analysis of a previous comparative survey (Priest, S., 2006) and subsequently tested against these newer data (Priest, S., 2005) this article describes the opinion climate for nanotechnology across North America. The comparison of key results from the two countries helps illustrate how social and cultural differences contribute to reactions to new technologies, including nanotech. The article also discusses implications for nanotechnology-related public outreach and risk communication efforts.  相似文献   
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