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11.
I. M. Endresen B. Ellertsen C. Endresen A. M. Hjelmen R. Matre H. Ursin 《Work and stress》1991,5(3):217-227
This study concerned the immunological correlates of stress and work. Self reported stress, emotional state, ego-strength, and defensiveness were examined in relation to measures of cellular immunity (T-cell response to Con A and number of T4 and T8 cells) and humoral immunity (concentrations of immunoglobulins and complement components in plasma) in a group of 96 Norwegian female bank employees. The analyses showed that workload, the stress factor with the highest group mean, was associated with number of T-cells, while strain due to body posture during work was related to concentrations of IgM and C3. Further, depression was significantly correlated with IgM concentration and T-cell number, and anxiety with C3 concentration. T-cell activity was the immunological parameter most consistently associated with psychological well-being, showing positive correlations with defensiveness and ego-strength and negative correlations with anxiety and depression. In conclusion, T-cell number and concentrations of IgM and C3 were sensitive to both work-related stress experience and emotional distress. Coping abilities, indicated by the MMPI Ego-strength scale and emotional distress, were reflected in T-cell activity; insufficient coping was associated with low T-cell activity. 相似文献
12.
loveLife is the largest effort ever launched in South Africa to change adolescent sexual behaviour with the aim of reducing the rate of HIV infection among 15–20 year olds by 50%, reducing other STIs, and reducing the incidence of teenage pregnancy. loveLife combines high-powered media awareness and education, development of adolescent-friendly reproductive health services, and outreach and support programmes. The 5-year research and evaluation plan includes a multi-year comprehensive observational study, tracking change in a range of behavioural indicators and in sexual health outcomes. In its first 2 years, loveLife reached more than 4 million youth. Sixty-two percent of youth and 59% of their parents/guardians recognize the brand, while the vast majority of parents (97%) and youth (89%) exposed to loveLife, identified loveLife as being positive. Challenges in the next years are the continued roll out of the programme, and the development of institutional support and behaviour change. 相似文献
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The authors present a new conceptual framework for assessing and treating traumatized college students. The framework, constructivist self-development theory (CSDT), blends object relations, self-psychology, and social cognition theories. It is founded upon a constructivist view of trauma in which the individual's unique history shapes his or her experience of traumatic events and defines the adaptation to trauma. Within this theory, the authors suggest approaches to setting the frame for trauma therapy, including stabilizing acute symptoms and setting appropriate expectations for treatment. CSDT provides a framework for the systematic assessment and practical treatment of three aspects of the self that are affected by trauma. These include self-capacities, or the ability to tolerate strong affect and regulate self-esteem; cognitive schemas, or beliefs and expectations about self and others in the areas of frame of reference (or identity and world view), safety, trust, esteem, intimacy, power, and independence; and intrusive trauma memories and related distressing affect. Finally, the authors provide guidelines for assessing the need for longer term treatment. 相似文献
15.
Michael I. Miller Sarang Joshi David R. Maffitt James G. Mcnally Ulf Grenander 《Journal of applied statistics》1994,21(1):141-163
Most real-world shapes and images are characterized by high variability- they are not rigid, like crystals, for example—but they are strongly structured. Therefore, a fundamental task in the understanding and analysis of such image ensembles is the construction of models that incorporate both variability and structure in a mathematically precise way. The global shape models introduced in Grenander's general pattern theory are intended to do this. In this paper, we describe the representation of two-dimensional mitochondria and membranes in electron microscope photographs, and three-dimensional amoebae in optical sectioning microscopy. There are three kinds of variability to all of these patterns, which these representations accommodate. The first is the variability in shape and viewing orientation. For this, the typical structure is represented via linear, circular and spherical templates, with the variability accomodated via the application of transformations applied to the templates. The transformations form groups: scale, rotation and translation. They are locally applied throughout the continuum and of high dimension. The second is the textural variability; the inside and outside of these basic shapes are subject to random variation, as well as sensor noise. For this, statistical sensor models and Markov random field texture models are used to connect the constituent structures of the shapes to the measured data. The third variability type is associated with the fact that each scene is made up of a variable number of shapes; this number is not assumed to be known a priori. Each scene has a variable number of parameters encoding the transformations of the templates appropriate for that scene. For this, a single posterior distribution is defined over the countable union of spaces representing models of varying numbers of shapes. Bayesian inference is performed via computation of the conditional expectation of the parametrically defined shapes under the posterior. These conditional mean estimates are generated using jump-diffusion processes. Results for membranes, mitochondria and amoebae are shown. 相似文献
16.
Tommi Härkänen Hannu Hausen Jorma I. Virtanen Elja Arjas 《Scandinavian Journal of Statistics》2003,30(3):523-533
Abstract A model is introduced here for multivariate failure time data arising from heterogenous populations. In particular, we consider a situation in which the failure times of individual subjects are often temporally clustered, so that many failures occur during a relatively short age interval. The clustering is modelled by assuming that the subjects can be divided into ‘internally homogenous’ latent classes, each such class being then described by a time‐dependent frailty profile function. As an example, we reanalysed the dental caries data presented earlier in Härkänen et al. [Scand. J. Statist. 27 (2000) 577], as it turned out that our earlier model could not adequately describe the observed clustering. 相似文献
17.
Current rounds of economic restructuring together with the changing priorities accorded to agricultural production are leading to significant shifts in rural property and tenure relations. This paper analyzes these processes with reference to rural Britain; it reports on empirical evidence collected in the county of Buckinghamshire in southeast England. Two significant types of new rural land development are considered—small-scale industrial units arising out of the conversion of agricultural buildings and golf course developments and their ancillary leisure-based activities. Post-war productionist forms of regulation and particularly established types of agricultural tenure are now being modified by farmers and nonagricultural interests committed to the development of rural land. New demands and market structures are requiring more diversity and flexibility by which land is owned, occupied, and used. These emergent, more flexible macro tenures are based on new sets of social and political alliances between farmers, developers, and local planning systems. Agricultural land is increasingly being viewed as a capital rather than as a productive asset associated with more volatile and regionally defined markets whose regulation is formative. 相似文献
18.
This article examines the origins of physicians and nurses who were admitted as permanent immigrants to the US from 1962-1979. Data are mainly from the Immigration and Naturalization Service. Countries used in the developmental analysis are only those whose population was estimated at 1 million or more as of mid-1979, encompassing 99% of the physicians and 97% of the nurses. Life expectancy at birth is the criterion used to differentiate origin countries by developmental dimension of health status. During the study period, health workers constituted about 30% of immigrants admitted to the US; of these, nurses and physicians constituted 72-82% throughout the study period. The period 1962-1979 has 4 distinct phases, marked by important legislative and/or policy changes; 1) 1962-1965, when the McCarran-Walter Act prevailed; 2) ending in 1968, the 2nd phase covers the transition mandated under the 1965 Immigration Act, which encouraged physician immigration; 3) the 3rd phase, 1969-1976, covers the transition to the 1976 Immigration and Nationality Act amendments; and 4) the 4th stage is 1977-1979. Results show that 1) under the McCarran-Walter Act, North America became the dominant physician source; 2) from 1966-1968, Asia attained dominance as the physician source and became even more predominant after 1968; 3) North America produced relatively few physicians in the early 1970s; 4) Europe produced substantially fewer physicians in the 1970s than in the 1960s; 5) South America, Africa, and Oceania were the lowest contributors of physicians; 6) during the McCarran-Walter years, North America and Europe produced almost 90% of nurses admitted into the US; 7) the 1965 Immigration Act and its aftermath resulted in Asia becoming the dominant source of nurses; 8) prior to the 1965 Immigration Act, Canada generated 20% of the aggregate number of physicians; 9) the Philippines surpassed Canada during the transition and India led after the transition; and 10) Canada supplied 30% of the nurses up through the transition, with the Philippines in the lead 1969-1979. Low health status countries were a relatively minor nurse source. Health status at the origin was a far less significant determinant of physician immigration than that of nurses. English language high and low health status country groups produced substantially more physician and nurse immigrants that their corresponding non-English language counterparts. The US attracted more physicians and nurses from less developed countries than more developed countries after 1968. 相似文献
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20.
Roeske-slomka I 《Polish population review / Polish Demographic Society [and] Central Statistical Office》1991,(1):89-104
Based on data from the 1973-83 Polish Family Budget Survey, this study examines the influence of income as a source of maintenance and income as a determinant of childbearing on family parity. It is assumed that income influences parity as a source of maintenance and as an influence on lifestyle or reproductive behavior. As a source of maintenance, the influence will be positive. As a life-style factor, it could be positive or negative. The hypotheses are 1) that positive influences are characteristics of older couples with a lower educational level and living in villages and small towns and income is a source of maintenance, and 2) a negative influence on parity reflects younger couples with higher educational levels from larger cities and income is a life-style factor. Some examples of how the theory of income influences total fertility are given in addition to a further elaboration of the theory. Other concepts introduced, as related to childbearing, are the value of goods and services with unchanged preferences and an increase in income, with preferences changing with income increases, with income preferences for nonprocreational and for procreational needs, and income as a factor influencing procreational needs and behavior. Correlation analysis is conducted for 33 subpopulations based on duration of marriage, educational level of the household, and size of residence. The results indicate that, in years 1973, 1975, and 1978 when income and parity are significant, the sign is positive. In 1980, there was a decrease in the number of subpopulations with a significant relationship, and in 3 subpopulations the results were negative. The 13 positive subpopulations were similar to those in the 1970s. In 1983, income explained an even smaller amount of parity. The subpopulations with a postive relationship usually have longer marriage durations, which suggest income as a source of maintenance. Negative results were among subpopulations with shorter marriage durations, which suggests life-style factor effects of income. 相似文献