自然伽马能谱测井谱解析方法研究

自然伽马能谱测井是重要的核测井方法之一，其地面信息处理系统的关键是实测谱解析技术。低分辨率是自然伽马能谱测井仪的固有弱点，且测井过程中信噪比较低，造成测井置信度不高。从自然伽马能谱测井原理出发，通过中海油实验数据处理后获得的放射性核素的标准计数率谱，对自然伽马能谱测井4种传统数据处理方法的优劣进行了对比，初步探讨了将灵敏度高、空间分辨率好的直接解调方法移植到自然伽马能谱测井谱解析中，为自然伽马能谱测井谱解析方法的选择提供了依据。     

Improving Cancer Dose–Response Characterization by Using Physiologically Based Pharmacokinetic Modeling: An Analysis of Pooled Data for Acrylonitrile-Induced Brain Tumors to Assess Cancer Potency in the Rat

Historically, U.S. regulators have derived cancer slope factors by using applied dose and tumor response data from a single key bioassay or by averaging the cancer slope factors of several key bioassays. Recent changes in U.S. Environmental Protection Agency (EPA) guidelines for cancer risk assessment have acknowledged the value of better use of mechanistic data and better dose–response characterization. However, agency guidelines may benefit from additional considerations presented in this paper. An exploratory study was conducted by using rat brain tumor data for acrylonitrile (AN) to investigate the use of physiologically based pharmacokinetic (PBPK) modeling along with pooling of dose–response data across routes of exposure as a means for improving carcinogen risk assessment methods. In this study, two contrasting assessments were conducted for AN-induced brain tumors in the rat on the basis of (1) the EPA's approach, the dose–response relationship was characterized by using administered dose/concentration for each of the key studies assessed individually; and (2) an analysis of the pooled data, the dose–response relationship was characterized by using PBPK-derived internal dose measures for a combined database of ten bioassays. The cancer potencies predicted for AN by the contrasting assessments are remarkably different (i.e., risk-specific doses differ by as much as two to four orders of magnitude), with the pooled data assessments yielding lower values. This result suggests that current carcinogen risk assessment practices overestimate AN cancer potency. This methodology should be equally applicable to other data-rich chemicals in identifying (1) a useful dose measure, (2) an appropriate dose–response model, (3) an acceptable point of departure, and (4) an appropriate method of extrapolation from the range of observation to the range of prediction when a chemical's mode of action remains uncertain.     

The State and Civil Society in Disaster Response

Abstract

This paper, based on the report “The State and Civil Society in Disaster Response: An Analysis of the Tamil Nadu Tsunami Experience,” (Srinivasan, Nagaraj, & Venkatesh, 2005) is essentially an empirical analysis of state and civil society responses in Tamil Nadu (India) to the tsunami of December 26, 2004. It examines interventions by state and non-state agencies, as well as people's experiences in the relief and rehabilitation phases to identify factors influencing both positive and negative outcomes of the tsunami response. Issues related to vulnerability and exclusion, equity, transparency and accountability in different sectors of disaster intervention are explored to highlight themes revolving around reach and efficacy of relief and recovery processes. These analyses bring out some interesting lessons with regard to the importance of institutional autonomy, non-politicized decision-making, and synergetic state-civil society interfaces in fostering inclusive, transparent and accountable rehabilitation processes. The roles played by institutional responsiveness and flexibility in shaping an effective disaster response also emerge very clearly from this study of the Tamil Nadu experience. Another crucial finding points to the need for detailed, reliable and disaggregated geo-demographic and socioeconomic records as a resource base for informing relief and rehabilitation interventions. The study draws extensively from the experiences and insights of people affected by, and involved in tsunami response, and from secondary knowledge resources available on the disaster.     

Discrimination between the complementary log-log and logistic model for ordinal data

An assessment is made of the number of observations on ordinal data necessary for reasonable power in a significance test of the null hypothesis of a logit model versus an alternative of a complementary log-log and vice versa. The conclusion is that quite modest numbers of observations, e.g. 50-100, are adequate provided that the boundaries of the ordinal scale are suitably defined.     

Engendering Response: Professional Gesture and the Assessment of Eyesight in Optometry Consultations

Many of the procedures undertaken within healthcare require specialized forms of participation that may be unfamiliar, even disturbing, to patients or clients. The practitioner has to encourage and enable participation in the investigation in an appropriate fashion while preserving the structure and integrity of the procedure. In this article, we consider optometry and the deployment of a vision test, known as subject refraction, that provides data to help determine the characteristics of any corrective lens that may be required by clients. The procedure's ability to establish robust and reliable data relies upon the optometrist's ability to encourage the client to respond to a series of stimuli without consideration or reflection. That is, the client is required to produce an unwitting response—conduct that might be considered nonsymbolic rather than symbolic. In this article, we also consider the optometrist's talk and bodily comportment during subjective refraction and how it serves to shape and determine the quality of the client's response and participation, and in turn to produce reliable test results.     

Cutting Experimental Designs into Blocks

Most experimental material in agriculture and industry is heterogeneous in nature and therefore its statistical analysis benefits from blocking. Many experiments are restricted in time or space, and again blocking is useful. This paper adopts the idea of orthogonal blocking of Box & Hunter (1957) and applies it to optimal blocking designs. This approach is then compared with the determinant-based approach described in the literature for constructing block designs.     

Estimation of regression models with equi-correlated responses when some observations on the response variable are missing

The present article deals with the problem of estimation of parameters in a linear regression model when some data on response variable is missing and the responses are equi-correlated. The ordinary least squares and optimal homogeneous predictors are employed to find the imputed values of missing observations. Their efficiency properties are analyzed using the small disturbances asymptotic theory. The estimation of regression coefficients using these imputed values is also considered and a comparison of estimators is presented.     

Stages of Supply Chain Disruption Response: Direct,Constraining, and Mediating Factors for Impact Mitigation

It is well established that supply chain disruptions can have a severe negative impact on firms and general wisdom suggests that this impact can be mitigated by quick responses. Aside from a few anecdotes, however, little is known about the decision‐making process that leads to speedy responses and about its impeding and supporting antecedents. Using the organizational information‐processing perspective, this empirical study unravels the disruption management process along a sequence of four stages—disruption recognition, disruption diagnosis, response development, and response implementation—and hypothesizes constraining and mediating effects of these stages. The findings contribute to an improved understanding of the role that the decision stages play in mitigating supply chain disruptions, and confirm the prediction that the speed with which information is processed and the stages are worked through positively affects supply chain performance. In addition, the findings suggest that one of the stages, diagnosis, acts as a constraining factor to the other stages. The stages also play a mediating role between the impact that the disruption has and a firm's readiness (prior to a disruption), dependence on a key supplier, and supply chain complexity. This provides guidance to decision makers in the application of resources both prior to a negative event and during a disruption recovery.     

从银幕到文本解构《欲望号街车》的两重性

《欲望号街车》的两个电影版本对原著的创作内涵做了截然不同的诠释。从比较两个电影版本改编的逻辑性入手,应用接受美学理论、知觉概念,对文本的叙述结构、人物性格及心理特征进行了分析,从而解构作品的两重性,从一个新的视点展示了成就这部伟大作品的原因。