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961.
Properties of measures and models of social mobility are analyzed in relation to the conceptualization of mobility. Two main objectives of mobility research are identified. One is the study of determinants of occupational achievement, the other is the study of mobility as a characteristic of social systems. It is shown that the realization of both objectives is hindered by a failure of commonly used models and measures of mobility to separate out the various individual and structural factors responsible for mobility.  相似文献   
962.
Not all elderly people need special care. This review refers to the dependent minority and to the services they need. Brief mention is made of the history of services which began with charitable relief by voluntary action, and the current relationship between government bodies and voluntary agencies is outlined. It is maintained that division of responsibility for the various types of care should be based on assessment of individual needs, decentralization of control, together with evaluation of the resources of the agencies concerned.  相似文献   
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THE recent British White Paper on post-war education in Englandleaves little doubt that Britain looks to a new era of education.The work has already begun. The British soldier of today willbe the key citizen of tomorrow. Cognizant of this fact, theBritish War Office has established a far-reaching program ofeducation for citizenship among England's troops. It is being carried out by the Army Educational Corps. Thisarticle is the story of their work. Mr. Bickersteth, educated at Christ Church, Oxford, and theUniversity of Paris, is Director of Army Education in the BritishWar Office. He is on leave as Warden of Hart House, Universityof Toronto.  相似文献   
966.
Conventional spirometry produces measurement error by using repeatability criteria (RC) to discard acceptable data and terminating tests early when RC are met. These practices also implicitly assume that there is no variation across maneuvers within each test. This has implications for air pollution regulations that rely on pulmonary function tests to determine adverse effects or set standards. We perform a Monte Carlo simulation of 20,902 tests of forced expiratory volume in 1 second (FEV1), each with eight maneuvers, for an individual with empirically obtained, plausibly normal pulmonary function. Default coefficients of variation for inter‐ and intratest variability (3% and 6%, respectively) are employed. Measurement error is defined as the difference between results from the conventional protocol and an unconstrained, eight‐maneuver alternative. In the default model, average measurement error is shown to be ~5%. The minimum difference necessary for statistical significance at p < 0.05 for a before/after comparison is shown to be 16%. Meanwhile, the U.S. Environmental Protection Agency has deemed single‐digit percentage decrements in FEV1 sufficient to justify more stringent national ambient air quality standards. Sensitivity analysis reveals that results are insensitive to intertest variability but highly sensitive to intratest variability. Halving the latter to 3% reduces measurement error by 55%. Increasing it to 9% or 12% increases measurement error by 65% or 125%, respectively. Within‐day FEV1 differences ≤5% among normal subjects are believed to be clinically insignificant. Therefore, many differences reported as statistically significant are likely to be artifactual. Reliable data are needed to estimate intratest variability for the general population, subpopulations of interest, and research samples. Sensitive subpopulations (e.g., chronic obstructive pulmonary disease or COPD patients, asthmatics, children) are likely to have higher intratest variability, making it more difficult to derive valid statistical inferences about differences observed after treatment or exposure.  相似文献   
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969.
One of the characteristics of modern industrial development is the emergence of a new typology of accidents whose effects can be spread, in space as well as in time, well beyond the borders of the installations where they occur, sometimes impacting the local population and the environment in a catastrophic fashion. This is the result of a number of factors that have changed the risk profile of modern industrial activities. For a number of reasons, the developing countries have proved to be more vulnerable to industrial disasters. Three of the most catastrophic industrial accidents—Bhopal, San Juan de Ixhuatepec, and Cubatão—occurred in developing countries, claiming thousands of lives. During the 1970s and 1980s the higher degree of public visibility of industrial hazards as a result of serious accidents, led to the creation, especially in the more industrialized countries, of regulations for greater control over industrial activities, either by means of new laws or by updating existing legislation. Some of these regulations were designed to improve the response to accidents with potential impacts outside the industrial sites. This article attempts to describe the current status and identify the shortcomings of off‐site emergency planning for hazardous industrial areas in Brazil. The most important problems are the lack of specific legislation and the absence of awareness and active participation of public authorities. The experience of an off‐site emergency planning process for a Brazilian industrial area is presented. This experience illustrates how difficult it is to prepare and implement emergency planning processes in an industrializing country.  相似文献   
970.
The April 1993 CPS differs from the March 1993 CPS in a number of respects. The April 1993 CPS supplement surveys only workers, whereas the March CPS examines the noncash benefits received by all Americans. The April CPS asks workers about health coverage in the week in which the questions were fielded, whereas the March CPS asks about coverage in the preceding year. In April 1993, there were 112.5 million civilian American workers between the ages of 18 and 64 with jobs. Eighty-two million (73 percent) of them worked for an employer that sponsored a health insurance plan, and 65 million (58 percent of all workers) participated in their employer's health plan. About one-third of workers at firms with fewer than 10 employees had employers who offer health benefits; about one-quarter of all of the workers in these firms participated in their employer's plan. Conversely, 94 percent of workers at firms with more than 1,000 employees had an employer who sponsored health benefits, and over 77 percent of these workers participated in their employer's plan. There are 16.5 million American workers whose employers sponsored health benefits but who did not participate in these benefits. Over one-half of these workers (8.5 million) chose not to be covered. Another 36 percent of these workers (5.9 million) did not participate because they were ineligible or denied coverage. Over 66 percent of the ineligible workers did not participate because they were part-time, contract, or temporary workers. Another 26 percent had not yet completed a probationary period. Among the reasons that those who chose not to participate in their employer's coverage, the vast majority (75 percent) stated they were covered by another health care plan. Twenty-nine percent stated that they chose not to purchase coverage because it was too costly or that they did not need or want the coverage. In 1993, there were 16.7 million workers with no health insurance coverage. The vast majority of these workers (95 percent) were employed by private employers. Sixty-six percent of the workers with no health insurance coverage were self-employed or worked for firms with fewer than 100 employees.  相似文献   
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