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61.
The effect of ethanol on the cigarette smoking of alcoholic subjects was studied in a residential laboratory. During daily 6-hr sessions, cigarettes were obtained either by request to the ward staff or by operation of a lever (fixed-ratio 5 or 10). In a mixed sequence across days, sessions involved ingestion of either vehicle (orange juice or vehicle plus ethanol (133.7 g). During ethanol sessions, the rate of cigarette smoking increased from 26% to 117% of vehicle levels. A series of control studies eliminated a number of potential behavorial mechanisms for the observed effect and indicated that the ethanol-induced increase in cigarette smoking occurred under a variety of experimental conditions: (1) when smoking could not occur concurrently with ethanol or vehicle consumption; (2) when subjects were not allowed to socialize; (3) when ingestion of ethanol or vehicle was scheduled for a number of consecutive days; (4) when various doses of ethanol were administered under blind conditions. In control experiments, weighing unsmoked tobacco and counting the number of puffs per cigarette indicated the effect was not due to smoking less of each cigarette. The effect was not limited to the experimental sessions alone, since total daily smoking was higher on ethanol days than vehicle days.  相似文献   
62.
A random effects probit model is developed for the case in which the same units are sampled repeatedly at each level of an independent variable. Because the observed proportions may be correlated under these conditions, estimating their trend with respect to the independent variable is no longer a standard problem for probit, logit or loglinear analysis. Using a qualitative analogue of a random regressions model, we employ instead marginal maximum likelihood to estimate the average latent trend line. Likelihood ratio tests of the hypothesis of no trend in the average line, and the hypothesis of no differences in average trend lines between experimental treatments, are proposed. We illustrate the model both with simulated data and with observed data from a clinical experiment in which psychiatric patients on two drug therapies are rated on five occasions for the presence or absence of symptoms.Supported by a grant from the MacArthur Foundation and National Science Foundation Grant BNS85-11774.The authors are indebted to James Heckman for calling our attention to the Clark algorithm.  相似文献   
63.
Proposed methods of assessing the statistical significance of interobserver agreements provide erroneous probability values when conducted on serially correlated data. Investigators who wish to evaluate interobserver agreements by means of statistical significance can do so by limiting the analysis to every k(th) interval of data, or by using Markovian techniques which accommodate serial correlations.  相似文献   
64.
为探讨学校归属感对青少年手机依赖的影响及其作用机制,基于阶段环境匹配理论,本研究采用问卷法对山东省青岛市65所中学3355名高二年级学生进行调查。结果表明:(1)在控制了性别和上网时间后,学校归属感对青少年手机依赖具有显著的负向预测作用;(2)学习焦虑在学校归属感与青少年手机依赖之间起部分中介作用;(3)学校归属感对青少年手机依赖的直接作用、学习焦虑的中介作用均受到同伴关系的调节,且相对于同伴关系水平低的个体,学校归属感对手机依赖、学校归属感对学习焦虑以及学习焦虑对手机依赖的作用都在同伴关系水平高的个体中更强。本研究有利于揭示学校归属感是如何影响青少年手机依赖的,以及在何种条件下对青少年手机依赖的影响更强/更弱,对移动互联网时代预防青少年手机依赖有一定启示意义。  相似文献   
65.
考察气质(意志控制、愤怒挫折、感觉寻求)对青少年烟酒使用的主效应,气质与教养方式(权威、专制、纵容)对烟酒使用的交互效应以及气质间的交互效应.采用随机整群抽样的方法,选取660名青少年为被试,匿名完成气质问卷、教养方式问卷和烟酒使用问卷.结果显示:(1)在控制了性别、年龄、社会经济地位后,气质对青少年烟酒使用具有预测作用,低意志控制、高愤怒挫折、高感觉寻求正向预测烟酒使用;(2)教养方式调节部分气质因素与烟酒使用的关系,具体为:权威和专制教养缓冲感觉寻求的风险作用,符合风险缓冲模型;纵容教养增强感觉寻求的风险作用,符合风险增强模型;(3)气质内部在影响青少年烟酒使用时也存在交互作用,愤怒挫折增强感觉寻求的风险作用,符合风险增强模型.因此,烟酒使用是气质与教养方式及气质间交互作用的产物.  相似文献   
66.
This is the first of three essays which use Edmund Husserl's dependence ontology to formulate a non-Diodorean and non-Kantian temporal semantics for two-valued, first-order predicate modal languages suitable for expressing ontologies of experience (like physics and cognitive science). This essay's primary desideratum is to formulate an adequate dependence-ontological account of order. To do so it uses primitive (proper) part and (weak) foundation relations to formulate seven axioms and 28 definitions as a basis for Husserl's dependence ontological theory of relating moments. The essay distinguishes between dependence v. independence, pieces v. moments, mediate v. immediate pieces and moments, maximal v. non-maximal pieces, founded v. unfounded qualities, integrative v. disintegrative dependence, and defines the concepts of the completion of an object, the adumbrational equivalence relation of objects, moments of unity which unify objects, and relating moments which relate objects. The eight theorems [CUT90]-[CUT97] show that relating moments of unity provide an adequate account of order in terms of primitive (proper) part and (weak) foundation relations.  相似文献   
67.
The authors asked how sport expertise modulates visual field dependence and sensory reweighting for controlling posture. Experienced soccer athletes, ballet dancers, and nonathletes performed (a) a Rod and Frame test and (b) a 100-s bipedal stance task during which vision and proprioception were successively or concurrently disrupted in 20-s blocks. Postural adaptation was assessed in the mean center of pressure displacement, root mean square of center of pressure velocity and ankle muscles integrated electromyography activity. Soccer athletes were more field dependent than were nonathletes. During standing, dancers were more destabilized by vibration and required more time to reweigh sensory information compared with the other 2 groups. These findings reveal a sport skill–specific bias in the reweighing of sensory inputs for spatial orientation and postural control.  相似文献   
68.
SUMMARY

This article looks at personal worth and identity, dependence, time and experience, change and loss, death, work and leisure from a distinctively Christian point of view that frees us from the distortions and dread of aging. We are called to embrace life as new creations through the years.  相似文献   
69.
Abstract

Direction dependence analysis (DDA) makes use of higher than second moment information of variables (x and y) to detect potential confounding and to probe the causal direction of linear variable relations (i.e., whether x?→?y or y?→?x better approximates the underlying causal mechanism). The “true” predictor is assumed to be a continuous nonnormal exogenous variable. Existing methods compatible with DDA, however, are of limited use when the relation of a focal predictor and an outcome is affected by a moderator. This study presents a conditional direction dependence analysis (CDDA) framework which enables researchers to evaluate the causal direction of conditional regression effects. Monte–Carlo simulations were used to evaluate two different moderation scenarios: Study 1 evaluates the performance of CDDA tests when a moderator affects the strength of the causal effect x?→?y. Study 2 evaluates cases in which the causal direction itself (x?→?y vs y?→?x) depends on moderator values. Study 3 evaluates the robustness of DDA tests in the presence of functional model misspecifications. Results suggest that significance tests compatible with CDDA are suitable in both moderation scenarios, i.e., CDDA allows one to discern regions of a moderator in which the causal direction is uniquely identifiable. An empirical example is provided to illustrate the approach.  相似文献   
70.
In a randomized controlled trial, we evaluated the efficacy of cognitive-behavioral treatment for insomnia to improve sleep and daytime symptoms, and to reduce relapse in recovering alcohol dependent (AD) participants. Seventeen abstinent AD patients with insomnia (6 women, mean age 46.2 ± 10.1 years) were randomized to 8 sessions of cognitive-behavioral treatment for insomnia for AD (CBTI-AD, n = 9) or to a behavioral placebo treatment (BPT, n = 8). Subjective measures of sleep, daytime consequences of insomnia and AD, alcohol use, and treatment fidelity were collected at baseline and post-treatment. Diary-rated sleep efficiency and wake after sleep onset, and daytime ratings of General Fatigue on the Multidimensional Fatigue Inventory improved more in the CBTI-AD compared to the BPT group. In addition, more subjects were classified as treatment responders following CBTI-AD. No group differences were found in the number of participants who relapsed to any drinking or who relapsed to heavy drinking. The findings suggest that cognitive-behavioral insomnia therapy benefits subjective sleep and daytime symptoms in recovering AD participants with insomnia more than placebo. The benefits of treating insomnia on drinking outcomes are less apparent.  相似文献   
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