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A~'n~cr. This report presents the current status of a series of studies oriented toward the assessment of perceived life quality. The conceptual model proposes that a person's overall sense of life quality is understandable as a combination of affective responses to life 'domains', which are of two types-role situations and values. Over 100 items used to measure a wide variety of domains and 28 items assessing perceived overall life quality are presented. Various subsets of these items were used in interviews with several representative samples of American adults. Based on these data the domain items were grouped into a smaller number of semi-independent clusters which were internally stable across 10 different subgroups of the respondents and whose interrelationships were highly replicable in independent national samples. A series of analyses, some replicated in more than one survey showed: (1) an additive combination of 12 selected domains explained 50-60 ~ of the variance in an index of overall life quality, (2) neither other domains nor several social characteristic variables contributed additional explanatory power, (3) this level of explanation was achieved in each of 22 subgroups of the population, and (4) additive combinations of domains worked as well as more complicated combinations. We are embarked on a major effort to develop measures of perceived life quality. The effort is part of the larger movement within the United States and a number of other countries to develop an expanded set of social indicators which can be monitored over time. It is hoped that through the generation and analysis of data from such indicators improvements can result in our understanding of the causes and directions of social changes, and in policymaking oriented toward efforts to improve the quality of life. Social indicators can be classified into two broad types: (1) those based on reports about experiences and characteristics of the reporter's own personal life, and (2) those based on reports of events or situations which are not part of the reporter's own life. Sometimes these two types of indicators have been referred to as 'subjective' and 'objective' respectively, though it can be argued that certain experiential measures are at least as objective as many of the so-called 'objective' measures. Examples of the first class of social indicators would include reports by respondents of their sense of safety when they go out alone at night, or their sense of satis

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IS900 PCR for Mycobacterium paratuberculosis was applied to cream, whey, and pellet fractions of centrifuged whole cows' milk. The test and simultaneous control reactions gave correct results for spiked milk and for native milk samples obtained directly from M. paratuberculosis-free, subclinically infected, and clinically infected cows. The test was then applied to units of whole pasteurized cows' milk widely obtained from retail outlets throughout central and southern England from September 1991 to March 1993. With peak periods in January to March and in September to November, when up to 25% of units were affected, an overall 22 of 312 samples (7%) tested positive for M. paratuberculosis. In 18 of the 22 positive samples (81%), the PCR signal segregated to the cream or pellet fractions or both, consistent with the presence of intact mycobacteria. Nine of 18 PCR-positive milk samples (50%) and 6 of 36 PCR-negative milk samples (16%) yielded long-term liquid cultures which tested positive for M. paratuberculosis after 13 to 40 months of incubation, despite overgrowth by other organisms. Taken together with data on the prevalence of M. paratuberculosis infection in herds in the United Kingdom, the known secretion of M. paratuberculosis in milk from subclinically infected animals, and the inability of laboratory conditions simulating pasteurization to ensure the killing of all these slowly growing or unculturable organisms, there is a high risk, particularly at peak times, that residual M. paratuberculosis will be present in retail pasteurized cows' milk in England.