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71.
The American Sociologist - Within the fields of anthropology and sociology, how do Democrats and Republicans compare in their opinions on issues of economic regulation, personal choice, and the...  相似文献   
72.
Louis Anthony Cox  Jr  . 《Risk analysis》2006,26(6):1581-1599
This article introduces an approach to estimating the uncertain potential effects on lung cancer risk of removing a particular constituent, cadmium (Cd), from cigarette smoke, given the useful but incomplete scientific information available about its modes of action. The approach considers normal cell proliferation; DNA repair inhibition in normal cells affected by initiating events; proliferation, promotion, and progression of initiated cells; and death or sparing of initiated and malignant cells as they are further transformed to become fully tumorigenic. Rather than estimating unmeasured model parameters by curve fitting to epidemiological or animal experimental tumor data, we attempt rough estimates of parameters based on their biological interpretations and comparison to corresponding genetic polymorphism data. The resulting parameter estimates are admittedly uncertain and approximate, but they suggest a portfolio approach to estimating impacts of removing Cd that gives usefully robust conclusions. This approach views Cd as creating a portfolio of uncertain health impacts that can be expressed as biologically independent relative risk factors having clear mechanistic interpretations. Because Cd can act through many distinct biological mechanisms, it appears likely (subjective probability greater than 40%) that removing Cd from cigarette smoke would reduce smoker risks of lung cancer by at least 10%, although it is possible (consistent with what is known) that the true effect could be much larger or smaller. Conservative estimates and assumptions made in this calculation suggest that the true impact could be greater for some smokers. This conclusion appears to be robust to many scientific uncertainties about Cd and smoking effects.  相似文献   
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WHY HOLD-UPS OCCUR: THE SELF-ENFORCING RANGE OF CONTRACTUAL RELATIONSHIPS   总被引:15,自引:0,他引:15  
Court enforcement and private enforcement are not alternative contract enforcement mechanisms, but are used jointly by transactors to define the self-enforcing range of a contractual relationship. Within this framework contract terms economize on the limited amounts of private enforcement capital possessed by transactors, either by directly controlling transactor behavior or by shifting private enforcement capital between transactors to coincide with likely future market conditions. Hold-ups occur when market conditions change sufficiently to place the relationship outside the self-enforcing range. This probabilistic view of hold-ups is contrasted with opportunism more generally and with moral hazard behavior.  相似文献   
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The purpose of this paper is to describe the various process deviations which can cause a runaway reaction to occur, and to discuss the experimental information necessary for risk assessment, the choice of a safe process, and the mitigation of the consequences of the runaway reaction. Ten typical hazardous process situations have been identified, considering various modes of initiation, homogeneous and heterogeneous, Arrhenius, and autocatalytic reactions. Each possible hazardous process deviation is illustrated by examples from the process industry and/or relevant experimental information obtained from laboratory experiments.  相似文献   
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The paper presents a comparative analysis of the relationship between rural-urban migration and fertility in Korea, Mexico, and Cameroon. Using an autoregressive model, the results show a significant rural-urban migration adaptation effect in Korea and Mexico, a reduction of 2.57 and 1.45 children during the entire childbearing period, respectively, when compared to a rural stayer, even after the effect of selection has been controlled. Rural-urban migration has a very small impact on fertility in Cameroon. The unexpected result for Cameroon is due to the fact that the fertility-increasing effect of urban residency on the improved supply conditions of births, such as reduced infertility, offsets the fertility-depressing effect of urban residency on the demand for births. As a result of the adaptation to urban fertility norms, the number of country-wide births was reduced significantly in Mexico and Korea over the time periods studied.  相似文献   
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