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General Point (general + point)
Selected AbstractsRadiochemical stability of 14C-compounds on storage: benefits of thioethersJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 3 2003Andreas Fredenhagen Abstract Storage of radiochemicals is a significant practical problem. Storage as a solution in various solvents was compared to the storage as a neat oil or solid over an extended period of time. Dichloromethane, a solvent previously not recommended for storage, was found to be a good choice in certain solvent mixtures. Addition of methylsulfide or 2-methyl-2-butene was shown to reduce the radiochemical decomposition by a factor of 1.7,3.2 in ethanol-free solvents. General points to consider for storage of radiochemicals are discussed. Radiochemical purity was determined by HPLC. Copyright © 2002 John Wiley & Sons, Ltd. [source] Design of an estimator of the kinematics of AC contactorsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 7 2009Jordi-Roger Riba Ruiz Abstract This paper develops an estimator of the kinematics of the movable parts of any AC powered contactor. This estimator uses easily measurable electrical variables such as the voltage across the coil terminals and the current flowing through the main coil of the contactor. Hence, a low cost microcontroller would be able to implement a control algorithm in order to reduce the undesirable phenomenon of contact bounce, which causes severe erosion of the contacts and dramatically reduces the electrical life and reliability of the contacts. To develop such an estimator is essential to have at our disposal a robust model of the contactor. Therefore, a rigorous parametric model that allows us to predict the dynamic response of the AC contactor is proposed. It solves the mechanic and electromagnetic coupled differential equations that govern the dynamics of the contactor by applying a Runge,Kutta-based solver. Several approaches have been described in the technical literature. Most of them are based on high cost computational finite elements method or on simplified parametric models. The parametric model presented here takes into account the fringing flux and deals with shading rings interaction from a general point of view, thus avoiding simplified assumptions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Regulation of Technology Transfer to Developing Countries: The Relevance of Institutional Capacity,LAW & POLICY, Issue 1 2005KEVIN E. DAVIS This article revisits the debate over appropriate approaches to the regulation of technology transfer to developing countries. It begins by contrasting two stylized approaches, labeled for convenience the "New International Economic Order" model and the "Globalization" model, which have historically struggled for acceptance. It then explores the implications for the choice between these or alternative models of the fact that many developing countries presently lack the institutional capacity required to provide optimal regulation of technology transfer. Existing discussions appear either to assume that developing countries possess sufficient institutional capacity to design and implement sophisticated regulatory regimes, or to take the opposite approach and assume a drastic shortage of institutional capacity. Both approaches ignore the intermediate category of countries that do face constraints upon institutional capacity but are striving to overcome them. The analysis here is intended to demonstrate the general point that a country's present and future institutional capacity ought to be considered highly relevant to the design of central aspects of the regime that it uses to regulate technology transfer. The analysis is also designed to highlight the specific need for attention to the distinctive questions of regulatory design which arise in countries that are in the process of enhancing their institutional capacity in this and other regulatory contexts. [source] CONTOURS OF AN ANTHROPOLOGY OF THE CHINESE STATE: POLITICAL STRUCTURE, AGENCY AND ECONOMIC DEVELOPMENT IN RURAL CHINATHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 3 2004Frank N. Pieke Anthropologists have long been inclined to view China from the perspective of a state-society dichotomy. In this model, the inevitable consequence of economic reform is that , especially at the local level , the state must yield more and more of its power to entrepreneurs, foreign investors, non-state organizations, and local communities. Not only does this approach distort the role of the state in society, but by placing the state above and outside society it also excludes it from the anthropological gaze. This article proposes an anthropology of the Chinese state which does not merely view the state in society, but also investigates the state itself as society. Drawing on fieldwork in northeastern Yunnan province, I illustrate this general point by investigating the changing role of the local state in economic development. This agenda for an anthropology of the Chinese state resonates both with the recent ,reinvention' of the subfield of political anthropology with its focus on governmentality, policy, and rights, and with recent calls by political scientists for the development of an interdisciplinary anthropology of the developmental state. [source] Regulatory Environment, Changing Incentives, and IPO Underpricing in the Korean Stock Market,ASIA-PACIFIC JOURNAL OF FINANCIAL STUDIES, Issue 2 2010Inseok Shin G24; G28; G32 Abstract I examine the importance of price support regulation in explaining IPO underpricing in the Korean stock market from 2001 through 2007. In contrast to the US practice where price support is provided effectively at the cost of the issuing firms, the price support in Korea resulted in direct costs to the underwriters. I construct a simple model to capture this feature of the regulation where IPO prices are determined through the interaction of the maximizing behaviors of underwriters and issuers. In the model, three variables, namely, the expected post-IPO price volatility, size of newly issued shares, and size of tradable shares, are specified to affect the opportunity costs of underpricing. When combined with the regulatory regime change in 2003, which lightened underwriters' obligations towards price support, the model implies that the magnitudes of the relationships between the three variables and underpricing have decreased since 2003. I test the hypotheses and find supportive empirical results: the relationship of underpricing with the expected price volatility has changed from positive to insignificant; those with sizes of newly issued and tradable shares from insignificant to negative. The findings contrast with existing Korean studies that do not find any evidence that price support regulation decreased the opportunity cost of underpricing for underwriters. The results also illustrate a more general point that to fully understand underpricing in a given stock market, it is crucial to take into account the regulatory environment that systematically influences agents' incentives to control or generate underpricing. [source] Climate change: a rational choice politics view,AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 3 2009Geoffrey Brennan Reduction in carbon dioxide emissions constitutes a global public good; and hence there will be strong incentives for countries to free ride in the provision of CO2 emission reductions. In the absence of more or less binding international agreements, we would expect carbon emissions to be seriously excessive, and climate change problems to be unsolvable. Against this obvious general point, we observe many countries acting unilaterally to introduce carbon emission policies. That is itself an explanatory puzzle, and a source of possible hope. Both aspects are matters of ,how politics works', i.e. ,public choice' problems are central. The object of this paper is to explain the phenomenon of unilateral policy action and to evaluate the grounds for ,hope'. One aspect of the explanation lies in the construction of policy instruments that redistribute strategically in favour of relevant interests. Another is the ,expressive' nature of voting and the expressive value of environmental concerns. Both elements , elite interests and popular (expressive) opinion , are quasi-constraints on politically viable policy. However, the nature of expressive concerns is such that significant reductions in real GDP are probably not sustainable in the long term , which suggests that much of the CO2 reduction action will be limited to modest reductions of a largely token character. In that sense, the grounds for hope are, although not non-existent, decidedly thin. [source] Musings on ADME Predictions and Structure,Activity RelationsCHEMISTRY & BIODIVERSITY, Issue 11 2005Bernard Testa The first part of the paper examines Structure,Activity Relations (SARs) and their components from a very general point of view. The various types of interpretation emerging from statistically valid relations will be examined, namely causal (mechanistic), contextual (empirical), fortuitous, and tautological correlations. Implications for ADME predictions will be seen when discussing the diversity of interactions between active compounds (e.g., drugs) and biological systems. The second part of the paper is more specific and presents the concept of molecular-property space, an all but neglected concept in SARs. Recent results from Molecular Dynamics (MD) simulations and Molecular Interaction Fields (MIF) computations of acetylcholine will be used to illustrate not only the well-known conformational space of this molecule, but also its property space as exemplified by its lipophilicity space. It will be seen that a molecule as small as acetylcholine is able to span a relatively broad property space. Most significantly in an ADME perspective, the molecule is able, within the limits of its property space, to adapt to the medium. This is equivalent to saying that the medium constrains the molecule to resemble it as much as feasible. [source] Detection, survival rates and dynamics of a cryptic plant, Asclepias meadii: applications of mark-recapture models to long-term monitoring studiesJOURNAL OF ECOLOGY, Issue 2 2009Helen M. Alexander Summary 1Analysis of population trajectories is central to assessing risk in populations of conservation concern. In animal studies, researchers realize that probabilities of detection of individuals are often less than one. Plants can also escape detection due to dormancy, herbivory, or observer error, but such information is rarely incorporated into population studies. 2We monitored a population of Asclepias meadii, a rare long-lived prairie perennial. Despite standardized methods, numbers of observed plants fluctuated greatly from 1992 to 2006. Individual plants often had periods of 1,5 years between initial and final sighting when no stems were found. To determine the actual population trajectories, we estimated rates of survival and population growth using mark-recapture models. We also estimated initial and resighting probabilities of detection. In 2007, we repeated surveys to identify reasons for low detection probabilities. 3We estimated 95% annual survival and a population growth rate of 1.023. Probabilities of initial detection were low (typically from 0.120 to 0.311 depending on prairie burn treatment), whereas average probability of detection for marked plants was 0.728. 4Comparisons of survival estimates from 15- and 8-year data sets revealed that survival estimates decline in the final years of a multi-year period, probably due to heterogeneity in encounter histories. 5By conducting three different surveys in 2007, we found that both herbivory over a multiple-week period and observer error contributed substantially to gaps in detection. 6Synthesis. Probabilities of detection that are less than one complicate interpretation of population dynamics, whether of mobile animals or inconspicuous plants. Our work illustrates three general points that could apply to many plant population studies: (i) mark-recapture models may provide insights on vital rates and population trajectories despite the extreme variability in count data that can arise because of low detectability, (ii) probabilities of initial detection can be quantified and can be considerably less than probabilities of resighting, and (iii) repeated surveys can help researchers determine the degree to which dormancy, herbivory, or observer error contribute to low probabilities of detection. Consideration of these points can improve the design and analysis of monitoring programs. [source] | |||||||||||||