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21.
Contemporary immigration to the United States and the formation of new ethnic groups are the complex and unintended social consequences of the expansion of the nation to its post-World War II position of global hegemony. Immigrant communities in the United States today are related to a history of American military, political, economic, and cultural involvement and intervention in the sending countries, especially in Asia and the Caribbean Basin, and to the linkages that are formed in the process that open a variety of legal and illegal migration pathways. The 19.8 million foreign-born persons counted in the 1990 U.S. census formed the largest immigrant population in the world, though in relative terms, only 7.9% of the U.S. population was foreign-born, a lower proportion than earlier in this century. Today's immigrants are extraordinarily diverse, a reflection of polar-opposite types of migrations embedded in very different historical and structural contexts. Also, unlike the expanding economy that absorbed earlier flows from Europe, since the 1970s new immigrants have entered an hourglass economy with reduced opportunities for social mobility, particularly among the less educated, and new waves of refugees have entered a welfare state with expanded opportunities for public assistance. This paper seeks to make sense of the new diversity. A typology of contemporary immigrants is presented, and their patterns of settlement, their distinctive social and economic characteristics compared to major native-born racial-ethnic groups, and their different modes of incorporation in—and consequences for—American society are considered.  相似文献   
22.
Dynamic reliability models with conditional proportional hazards   总被引:1,自引:0,他引:1  
A dynamic approach to the stochastic modelling of reliability systems is further explored. This modelling approach is particularly appropriate for load-sharing, software reliability, and multivariate failure-time models, where component failure characteristics are affected by their degree of use, amount of load, or extent of stresses experienced. This approach incorporates the intuitive notion that when a set of components in a coherent system fail at a certain time, there is a jump from one structure function to another which governs the residual lifetimes of the remaining functioning components, and since the component lifetimes are intrinsically affected by the structure function which they constitute, then at such a failure time there should also be a jump in the stochastic structure of the lifetimes of the remaining components. For such dynamically-modelled systems, the stochastic characteristics of their jump times are studied. These properties of the jump times allow us to obtain the properties of the lifetime of the system. In particular, for a Markov dynamic model, specific expressions for the exact distribution functions of the jump times are obtained for a general coherent system, a parallel system, and a series-parallel system. We derive a new family of distribution functions which describes the distributions of the jump times for a dynamically-modelled system.  相似文献   
23.
Composition-consistent tournament solutions and social choice functions   总被引:1,自引:1,他引:0  
This paper introduces a new axiom for choice in preference profiles and tournaments, called composition-consistency. A social choice function is composition-consistent if it is non-sensitive to the cloning of one or several outcomes. The key feature of the composition consistency property is an operation concept called multiple composition product of profiles. The paper provides a brief overview of some social choice functions studied in the literature. Concerning the tournament solutions, it is proved that the Top Cycle, the Slater and the Copeland solutions are not composition-consistent, whereas the Banks, Uncovered Set, TEQ, Minimal Covering Set are composition-consistent. Moreover, we define the composition-consistent hull of a solution as the smallest composition-consistent solution containing . The composition-consistent hulls of the Top cycle and Copeland solutions are specified, and we give some hints about the location of the hull of the Slater set. Concerning social choice functions, it is shown that Kemeny, Borda and Minimax social choice functions are not composition-consistent, whereas the Paretian one is composition-consistent. Moreover, we prove that the latter is the composition-consistent hull of the Borda and Minimax functions.  相似文献   
24.
Conclusion The nursery school may be considered an institution and a market where the habits produced by the family are moulded, developed and standardized; thus, it is confronted with an objective definition of early childhood embedded in pedagogical practices. The proper objective of a sociology of nursery-school practice is the analysis of the lag between the functions delegated to the school by the different social classes and the functions which it objectively tends to fulfill. Here we have the best test of the lag between the pedagogic demands of the different classes and what the schools supply-which is very abstract, with results that are only visible at a later stage in the school career. It is not so much a question of learning to read or of preparing to do so (the acquisition of certain logical operations or a developed sensitivity, of acquiring a few I.Q. points). This learning takes place through many varied activities which apppear to be far from the learning function.All told, the conditions for understanding nursery-school exercises flow from the conditions for inventing these exercises. For instance, in games of manipulation, construction, classifying various objects, is not some knowledge of Piaget (at least in the sense of some psychologikal knowledge) needed to understand that practical manipulation is also logical manipulation, to see in cube games the learning of logic? Similarly, the language naïveté cultivated in language games is a clever naïveté, which supposes for example a cultured re-discovery of popular archaic language or of child talk. p ]Is it not likely to appear as pure childishness to those who, without the ncessary cultural knowledge, do not have the keys to decipher these ostensibly naïve exercises? Similarly, the conditions for understanding children's drawings as artistic learning (and the nursery school as an educational institution) are the very conditions for understanding modern art as art.It is not just a matter of perception and understanding; as the objective definition of early childhood proper to the different social classes becomes pervasive both in the relationship with school and in the socialization practices of the family, it patterns the children's habitus (as long-lasting internalized dispositions), which in turn influence the child's behavior and attitude towards school.The perception categories and the different forms of treatment of young children appropriate to each social class are not simply the result of the diffusion of definitions of early childhood produced by the autonomous evolution of scientific and artistic disciplines. They are the products of all the social and cultural conditions which define the class situation. We may also wonder whether at least some pedagogy and certain types of exercises do not presume that the child has socially marked attitudes, produced in some classes by family inculcation. For instance, a general attitude of disinterested interest is required by a pedagogy offering multiple activities and open to an attitude of active research and exploration. Does not this attitude suppose as an existential possibility the condition of social classes protected from economic pressure and from the urgency of immediate life, a general attitude towards life nearer to leisure than to the constraints of work?Thus, in confronting supply with demand—here even less than elsewhere-there is no question of comparing the expectations arising from users' opinions with the program offered in the official definition of the institution. The expectations are those which arise from objective determinations inherent in each social group, the forms of treatment and perception of early childhood. To analyze the program-and therefore to ascertain the social conditions governing the use of the nursery school—the dominant definition of early childhood on which the institution is founded must be brought to light. Moreover, the way in which this definition is written into the curriculum (and, subsequently, into pedagogical practice) must also be studied. This implies that the preliminary condition for a sociological analysis of the functions performed by the nursery school for the different social classes would be an analysis of a) the components of this dominant definition of early childhood and b) of the social conditions in those groups which make it possible to identify these components.We wish to thank P. Bourdieu for his advice during our research. R. Collins provided useful suggestions after reading the first version of this paper.  相似文献   
25.
26.
For over 20 years, family therapist Karl Tomm has been engaging families and couples with a therapeutic intervention he calls Internalized Other Interviewing (IOI). The IOI (cf. Emmerson‐Whyte, 2010; Hurley, 2006) entails interviewing clients, from the personal experiences of partners and family members as an internalized other. The IOI is based on the idea that through dialogues over time, one can internalize a sense of one's conversational partner responsiveness in reliably anticipated ways. Anyone who has thought in a conversation with a family member or partner, “Oh there s/he goes again,” or anticipates next words before they leave the other's mouth, has a sense of what we are calling an internalized other. For Tomm, the internalized anticipations partners and family members may have offers entry points into new dialogues with therapeutic potential—particularly, when their actual dialogues get stuck in dispreferred patterns.  相似文献   
27.
To compare two modes of administration (self-administered; by interviewer) and two response options format (using words; images of “facial-expressions”) of the first question of SF-36 (Q1SF-36), and to test its validity. We included 825 participants (20–90 years). Q1SF-36, using words or images, was included in a global questionnaire interview and at the end participants filled the SF-36. The agreement was tested by weighted kappa coefficients (WKappa). Classification Trees were used in the calibration of Q1SF-36 responses, with the physical (PDSF36) and mental dimensions of SF-36. Polyserial correlation coefficients and areas under the ROC curves (AUC) were used for validation. After categorization, using PDSF36 classification trees, the WKappa were 0.770 (self-administered vs. interviewer), 0.569 (self-administered vs. facial-expressions) and 0.566 (interviewer vs. facial-expressions). The WKappa between the PDSF36 and the modes (self-administered, interviewer and facial-expressions) were 0.784, 0.713 and 0.579 and the corresponding polyserial correlation coefficients were 0.784, 0.713 and 0.579. A good discriminatory power was found comparing the modes with the PDSF36 (AUC = 0.907, 0.923 and 0.827), but not with mental dimension (AUC = 0.538, 0.501 and 0.629). The Q1SF-36, by self-administration or interviewer, may be a valid alternative for assessment of subjective physical health, but not mental health.  相似文献   
28.
Wavelet thresholding of spectra has to be handled with care when the spectra are the predictors of a regression problem. Indeed, a blind thresholding of the signal followed by a regression method often leads to deteriorated predictions. The scope of this article is to show that sparse regression methods, applied in the wavelet domain, perform an automatic thresholding: the most relevant wavelet coefficients are selected to optimize the prediction of a given target of interest. This approach can be seen as a joint thresholding designed for a predictive purpose. The method is illustrated on a real world problem where metabolomic data are linked to poison ingestion. This example proves the usefulness of wavelet expansion and the good behavior of sparse and regularized methods. A comparison study is performed between the two-steps approach (wavelet thresholding and regression) and the one-step approach (selection of wavelet coefficients with a sparse regression). The comparison includes two types of wavelet bases, various thresholding methods, and various regression methods and is evaluated by calculating prediction performances. Information about the location of the most important features on the spectra was also obtained and used to identify the most relevant metabolites involved in the mice poisoning.  相似文献   
29.
In this essay, I present an interdisciplinary examination of the state of research in Latino education, addressing not only the cultural forces influencing Latinos’ educational attainment, but also the structural conditions faced by them—as a racialized minority group—throughout their schooling and that have a cumulative effect on their academic attainment. Overall, I suggest that by engaging in a critical review of the literature on Latinos’ educational attainment, the reader will acknowledge that the racially driven hierarchical structural arrangements are highly responsible for the patterns observed.  相似文献   
30.
The objectives of this study were to describe the different modalities of physical activity programs designed for moderate to severe dementia and to identify their impact on functional independence in activities of daily living (ADL). A critical review of randomized controlled trials related to the impact of physical activity programs in moderately to severely demented persons on ADL performance and meta-analysis of the identified studies were performed. Among the 303 identified articles, five responded to the selection criteria. Four out of the five studies demonstrated limited methodological quality. In one high-quality study, physical activity programs significantly delayed deterioration of ADL performance. The program components and ADL assessment tools vary widely across studies. Although the proposed treatments have not proven their efficiency in improving the ADL status of the patients, they were able to limit the decline in ADL functioning. Future research is warranted in order to identify clinically relevant modalities for physical activity programs for people with moderate to severe dementia.  相似文献   
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