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261.
In this paper I want to describe the use of a technique which I have termed the ‘Time Sphere’. The combination of a life cycle model with the chronological mapping of closeness–distance has allowed for useful consideration of various relational events not previously explored by the family or therapist. By sharing the information visually with the client family we are able to explore context, family of origin influences and life cycle transitions within an extended family model. Ultimately my hope is to develop this model further as a creative means of exploring how family patterns and relationships are repeated, and how context is ultimately the key to understanding. To preserve confidentiality, my ‘case’ is an amalgam of several real client families.  相似文献   
262.
飞机一进入非洲南部国家纳米比亚的首都温德和克,就像进入了一个自然保护区。由于温德和克位于中央高原上,并且以阿瓦斯山脉为天然屏障,游客一进入该市就能问或看见捻角羚和其他羚羊,这不是什么稀罕事。  相似文献   
263.
The system of full mobilisation and the modest effects of the World War II events on the civil population make Finland a highly useful case for exploring whether war veterans have elevated long-term mortality risks. Using data from the Human Mortality Database and a register-based micro sample with main causes of death, we study men in the cohorts who participated in the wars against the Soviet Union in 1939–1944. For these war cohorts, we find no indications of reduced survival after the early 1950s, as compared with male cohorts without combat experience. The absence of a long-term effect might be an artefact of mortality selection. In the first few years after war-end, death rates remained relatively high because of infectious diseases that killed off the weakest of the survivors. The results are in line with a series of other studies and illustrate that in the potential presence of cohort inversion there are no visible long-term effects of war experience on later-life survival.  相似文献   
264.
Using data for 555,038 pregnancies conceived in the Czech Republic in 1987-1990, we show that pronounced differences in fetal survival in the middle trimester of pregnancy by marital status, educational level, and labor force attachment become much smaller at full term; survival differences by age at conception and number of previous deliveries show relatively constant proportional hazards throughout gestation. Social inequalities in postpartum life chances have been documented previously, but we show that similar inequalities exist before birth.  相似文献   
265.
The food industry faces two paradoxical demands: on the one hand, foods need to be microbiologically safe for consumption and on the other hand, consumers want fresh, minimally processed foods. To meet these demands, more insight into the mechanisms of microbial growth is needed, which includes, among others, the microbial lag phase. This is the time needed by bacterial cells to adapt to a new environment (for example, after food product contamination) before starting an exponential growth regime. Since food products are often contaminated with low amounts of pathogenic microorganisms, it is important to know the distribution of these individual cell lag times to make accurate predictions concerning food safety. More precisely, cells with the shortest lag times (i.e., appearing in the left tail of the distribution) are largely decisive for the outgrowth of the population. In this study, an integrated modeling approach is proposed and applied to an existing data set of individual cell lag time measurements of Listeria monocytogenes. In a first step, a logistic modeling approach is applied to predict the fraction of zero-lag cells (which start growing immediately) as a function of temperature, pH, and water activity. For the nonzero-lag cells, the mean and variance of the lag time distribution are modeled with a hyperbolic-type model structure. This mean and variance allow identification of the parameters of a two-parameter Weibull distribution, representing the nonzero-lag cell lag time distribution. The integration of the developed models allows prediction of a global distribution of individual cell lag times for any combination of environmental conditions in the interpolation domain of the original temperature, pH, and water activity settings. The global fitting quality of the model is quantified using several measures indicating that the model gives accurate predictions, erring slightly on the fail-safe side when predicting the shortest lag times.  相似文献   
266.
Summary.  Previous research has proposed a design-based analysis procedure for experiments that are embedded in complex sampling designs in which the ultimate sampling units of an on-going sample survey are randomized over different treatments according to completely randomized designs or randomized block designs. Design-based Wald and t -statistics are applied to test whether sample means that are observed under various survey implementations are significantly different. This approach is generalized to experimental designs in which clusters of sampling units are randomized over the different treatments. Furthermore, test statistics are derived to test differences between ratios of two sample estimates that are observed under alternative survey implementations. The methods are illustrated with a simulation study and real life applications of experiments that are embedded in the Dutch Labour Force Survey. The functionality of a software package that was developed to conduct these analyses is described.  相似文献   
267.
The authors consider the linear model Yn = ψXn + ?n relating a functional response with explanatory variables. They propose a simple test of the nullity of ψ based on the principal component decomposition. The limiting distribution of their test statistic is chi‐squared, but this distribution is also an excellent approximation in finite samples. The authors illustrate their method using data from terrestrial magnetic observatories.  相似文献   
268.
This study investigates the effects of maternal education on child’s health and health behavior. We draw on a rich German panel data set containing information about three generations. This allows instrumenting maternal education by the number of her siblings while conditioning on grandparental characteristics. The instrumental variables approach has not yet been used in the intergenerational context and works for the sample sizes of common household panels. We find substantial effects on health behavior for adolescent daughters, but neither for adolescent sons nor for the health status of newborns. We show that possible concerns for the validity of the instrument are unlikely to compromise these results. We discuss mother’s health behavior, assortative mating, household income, and child’s schooling track as possible channels of the estimated effects. Maternal education seems to affect daughter’s smoking behavior through the higher likelihood of the daughter pursuing a higher secondary schooling track.  相似文献   
269.
电子类专业学生创新和实践能力培养模式探析   总被引:1,自引:0,他引:1  
本文针对电子科学技术相关专业,阐述了电子类专业学生的创新精神和实践能力培养模式的改革思路,指出了电子类专业教学内容和课程体系结构的更新和优化的特点以及学生创新精神和实践能力培养具体运行模式和方法等.  相似文献   
270.
This issue aims to demonstrate the practical value of studying a range of social problems in interpersonal, intragroup, and intergroup situations from a perspective of power and influence processes. In doing so, it extends the currently rapidly developing theoretical and experimental work on power and influence phenomena in a practical direction. This introductory article gives a brief historical overview of the area of social power and influence tactics by describing the core theoretical ideas.  相似文献   
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