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141.
This article investigates care provided to parents and parents-in-law by mid-life adults with dependent children at home. Data from the General Household Survey are used first to estimate the prevalence of this 'two-way' care over the past decade, and second to develop forecasts of two-way care for a generation of women who have just finished their childbearing years. Having a higher education qualification is associated with later ages both of caring for parents and of having children at home. Increasingly late first childbearing, however, points towards a potentially greater caring 'squeeze' for higher-qualified women, with a little over 1 in 10 at age 45 projected to be caring for a parent while still having a child under 18 in the household. 相似文献
142.
In occupational therapy education in South Africa, community service (CS) focuses learning opportunities during fieldwork placements. CS therefore enabled the researcher to utilise successive small scale research projects to guide learning of students during fieldwork while simultaneously developing the occupational therapy service at a residential care facility. This community setting provided a powerful environment through which research, in combination with opportunities for reflection, contributed to nurturing skills needed by these future health professionals. A technical action research (AR) approach incorporated AR cycles and opportunities for structured reflection. Therefore situations were created for the students to embrace experiential learning. Experiential learning in the form of anticipatory reflection, reflection-in-action, reflection on reflection and retrospective reflection impacted on the quality of the students’ work. Besides encouraging unique leaning opportunities for students when engaging in research during their fieldwork placement, engagement in AR cycles simultaneously improved service delivery to residents in the facility. Key benefits of this investigation were that fieldwork education utilising AR cycles within a CS situation promoted students to identify voids in their theoretical background as well as practice skills; to apply reflective practice that could contribute to their personal and professional development; and to utilize learning opportunities optimally. Despite positive gains showed by this study, the role of power relations between the researcher as fieldwork educator and the students prohibited the AR cycles from being more emancipatory in nature and should be addressed in follow-up studies. 相似文献
143.
Family change, when adults depart or arrive around children, raises policy issues. Its measurement depends upon the evidence collected and from whom. This paper compares British children's histories obtained from fathers and mothers. The evidence, on one birth cohort of parents, comes from two sources: the National Child Development Study and the ONS Longitudinal Study. The resulting account of family change is not substantially different between parents. There is some under-reporting of children not living with their fathers. This is due to under-reporting by those included in the studies and to under-representation in them of absent fathers and lone parents. 相似文献
144.
Daniel S. Yeung Wing W. Y. Ng Aki P. F. Chan Patrick P. K. Chan Michael Firth Eric C. C. Tsang 《系统科学与系统工程学报(英文版)》2007,16(2):166-180
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset. 相似文献
145.
146.
Michael Steel 《Journal of Classification》1992,9(1):91-116
In taxonomy and other branches of classification it is useful to know when tree-like classifications on overlapping sets of
labels can be consistently combined into a parent tree. This paper considers the computation complexity of this problem. Recognizing
when a consistent parent tree exists is shown to be intractable (NP-complete) for sets of unrooted trees, even when each tree
in the set classifies just four labels. Consequently determining the compatibility of qualitative characters and partial binary
characters is, in general, also NP-complete. However for sets of rooted trees an algorithm is described which constructs the
“strict consensus tree” of all consistent parent trees (when they exist) in polynomial time. The related question of recognizing
when a set of subtrees uniquely defines a parent tree is also considered, and a simple necessary and sufficient condition
is described for rooted trees.
This work was supproted by the Alexander von Humoldt-Stiftung. I wish to thank Andreas Dress, Hans-Jürgen Bandelt and the
referees for their helpful comments. 相似文献
147.
148.
Clustering the rows and columns of a contingency table 总被引:1,自引:2,他引:1
Michael J. Greenacre 《Journal of Classification》1988,5(1):39-51
A number of ways of investigating heterogeneity in a two-way contingency table are reviewed. In particular, we consider chi-square decompositions of the Pearson chi-square statistic with respect to the nodes of a hierarchical clustering of the rows and/or the columns of the table. A cut-off point which indicates significant clustering may be defined on the binary trees associated with the respective row and column cluster analyses. This approach provides a simple graphical procedure which is useful in interpreting a significant chi-square statistic of a contingency table.The author gratefully acknowledges the constructive comments of the referees and the editor. 相似文献
149.
Cellular responses to mild heat stress 总被引:12,自引:0,他引:12
Since its discovery in 1962 by Ritossa, the heat shock response has been extensively studied by a number of investigators to understand the molecular mechanism underlying the cellular response to heat stress. The most well characterized heat shock response is induction of the heat shock proteins that function as molecular chaperones and exert cell cycle regulatory and anti-apoptotic activities. While most investigators have focused their studies on the toxic effects of heat stress in organisms such as severe heat stress-induced cell cycle arrest and apoptosis, the cellular response to fever-ranged mild heat stress has been rather underestimated. However, the cellular response to mild heat stress is likely to be more important in a physiological sense than that to severe heat stress because the body temperature of homeothermic animals increases by only 1–2°C during febrile diseases. Here we provide information that mild heat stress does have some beneficial role in organisms via positively regulating cell proliferation and differentiation, and immune response in mammalian cells.Received 14 May 2004; received after revision 2 August 2004; accepted 16 August 2004 相似文献
150.
Human peripheral blood monuclear cells transfected with messenger RNA stimulate antigen-specific cytotoxic T-lymphocytes in vitro 总被引:1,自引:0,他引:1
Teufel R Carralot JP Scheel B Probst J Walter S Jung G Hoerr I Rammensee HG Pascolo S 《Cellular and molecular life sciences : CMLS》2005,62(15):1755-1762
The efficiency of test vaccines needs to be evaluated by quantification of the triggered cellular immune response. Usually, for these assays, autologous target cells expressing the vaccine antigen are required. In the context of messenger RNA (mRNA)-based vaccinations, the target cells used for the read-out are mRNA-transfected monocyte-derived dendritic cells (Mo-DCs). Their production typically requires samples of 100 ml blood from the patients, and limits the number of assays that can be performed. We show here that fresh peripheral blood mononuclear cells (PBMCs) can be transfected with mRNA by electroporation. Such cells are as efficient as mRNA-transfected Mo-DCs for their ability to activate memory T cells in vitro. Thus, mRNA-transfected PBMCs are a convenient replacement of mRNA-transfected Mo-DCs for the in vitro monitoring of natural or vaccine-induced immune responses.Received 17 February 2005; received after revision 1 May 2005; accepted 7 Juni 2005 相似文献