The incidence of genotypes at codon 171 of the prion protein gene (PRNP) in five breeds of sheep and production traits of ewes associated with those genotypes.

Scrapie is one of several transmissible spongiform encephalopathies of livestock. Disease susceptibility is linked to polymorphisms in the normal prion protein gene that encodes the mammalian prion precursor. Codon 171 of this gene is a major determinant of scrapie susceptibility. Selection for arginine (R) at codon 171 is encouraged by the USDA to decrease the incidence of scrapie. Objectives of this study were to determine the frequency of R allele variants at codon 171 in a sample of sheep from five breeds (Columbia, Hampshire, Rambouillet, Suffolk, and Targhee) and western white-faced commercial ewes and to determine whether the R allele is associated with ewe and lamb production traits. Genotyping was performed on 532 ewes and 901 lambs from the University of Wyoming flock, in addition to 820 rams from 52 sheep producers from Wyoming and surrounding areas, using a DNA mismatch assay that discriminated the R allele from others at codon 171. Genotyping was performed by DNA sequencing on 127 rams representing all breeds, except Hampshire from the USDA Sheep Experiment Station at Dubois, ID. The 171R allele was found in all five breeds and in the commercial western white-faced ewes. Genotype frequencies varied (P < 0.001) by breed in ewe and ram populations. Influence of R-allele frequency on ewe lambing records and individual lamb records was analyzed for Columbia (62, 161, 121), Hampshire (89, 193, 162), Rambouillet (87, 179, 133), Suffolk (67, 178, 161), and commercial sheep (227, 463, 324) for numbers of ewes, total number of ewe production records, and individual lamb records, respectively. Suffolk ewes without the R allele (non-R/non-R) gave birth to more (P or= 0.08) by ewe genotype. Lamb birth and weaning weights were not influenced (P >or= 0.12) by lamb genotype in any of the breeds or in the commercial flock. In this population, ultimate lamb production was only influenced by genotype at codon 171 in the Suffolk flock.

Measuring the quality of medical records: a method for comparing completeness and correctness of clinical encounter data.

This paper explores the attributes of quality in recorded clinical encounter data, examines issues in measuring these attributes, and describes a method for measuring two attributes, completeness and correctness. The method is defined in the context of computer-based records and is demonstrated in a pilot study. Videotaped physician-patient encounters and an empiric process of determining a gold standard for content are used. The methodology was found to be feasible. Problems encountered during the pilot study can be remedied.

The use of a standardized terminology for comparison of free text and structured data entry.

The Minimal Standard Terminology (MST) for gastrointestinal endoscopy, the product of an international effort, is to be been used in a study comparing free text to structured reports of esophagogastroduodenoscopies (EGDs). This requires some assumptions and adaptations in order to map to the MST in a uniform and quantifiable manner. Initial mapping has suggested a number of problem areas which require further investigation.

Top researchers and institutions in mental retardation: 1979-1999.

The identification of leading researchers and institutions is important in clarifying expert resources in the area of developmental disabilities. We assessed productivity of authors and research institutions in this area. Journals were peer-reviewed, published in the English language, and were focused on developmental disabilities. Researchers were tabulated without regard to order of authorship. Results identified prominent leaders in research, the top 3 researchers accounting for a significant portion of research completed over the last 20 years. The majority of researchers identified were male and affiliated with university settings. Results also revealed a need for an increase in productivity across service delivery settings.

Psychopharmacology and mental retardation: a 10 year review (1990-1999).

We conducted a 10 year review of the literature pertaining to psychopharmacology and mental retardation. Studies were included or excluded from the review based on meeting one or more of the methodological criteria normally considered fundamental for sound scientific research. The vast majority of studies conducted in the last 10 years in this area had major methodological flaws. While a large number of medications were prescribed for various psychological disorders and behavior problems, most drug administrations were not based in science, were not evaluated appropriately, and generally did not follow best practices for treatment of persons with mental retardation. Very few medications prescribed were behavior or psychiatric symptom specific; that is, most medications were given to suppress a myriad of aberrant behaviors thus chemically restraining the individual in question. Practices such as these present serious problems for service providers due to the deleterious side effects of many psychotropic medications and the federal government's intervention into the care-provision practices of developmental centers, community homes, and other living arrangements for persons with mental retardation. Implications of our review are discussed.

Intergenerational relations in urban China: proximity, contact, and help to parents.

Although most older Chinese parents live with an adult son or daughter, most adult offspring do not live with parents. We examine the relations of these noncoresident offspring with parents in terms of proximity, frequency of contact, and exchange of help. Based on a 1993 random sample survey conducted in two major Chinese cities, we find that although rates of coresidence are high, noncoresident sons and daughters live close to parents, have frequent contact with their parents, and provide regular help to parents. Relationships with noncoresident sons and daughters are unaffected by whether parents coreside with another child. There is some evidence of closer relationships with sons than with daughters, but parents without a son receive as much help from all children as do parents with sons. The effects of these and other predictors are estimated in multivariate analyses, and results are interpreted in terms of the persistence or change of traditional family norms.

Making a place in the metropolis: locational attainment in cities and suburbs.

What accounts for the differences in the kinds of communities within the metropolis in which members of different racial and ethnic groups live? Do socioeconomic advancement and acculturation provide greater integration with whites or access to more desirable locations for minority-group members? Are these effects the same for Asians or Hispanics as for blacks? Does suburbanization offer a step toward greater equality in the housing market, or do minorities find greater discrimination in the suburban housing market? Data from 1980 for five large metropolitan regions are used to estimate "locational-attainment models," which evaluate the effects of group members' individual attributes on two measures of the character of their living environment: the socioeconomic standing (median household income) and racial composition (proportion non-Hispanic white) of the census tract where they reside. Separate models predict these outcomes for whites, blacks, Hispanics, and Asians. Net of the effects of individuals' background characteristics, whites live in census tracts with the highest average proportion of white residents and the highest median household income. They are followed by Asians and Hispanics, and-at substantially lower levels-blacks. Large overall differences exist between city and suburban locations; yet the gap between whites and others is consistently lower in the suburbs than in the cities of these five metropolitan regions.

Self-interest and altruism in intergenerational relations.

Self-interest and altruism in the relationships between generations can be manifested both within the family and in the public arena. The present study compares levels of support between age groups 40-49, 50-59, 60-69, 70-79, and 80+ on a series of attitudes about "appropriate" parent-child relationships and governmental programs for older people. On both kinds of measures, older people tend consistently to be least likely to adopt the "pro-elderly" position. This association is maintained when controls are introduced in multivariate analyses. Altruism, not self-interest, seems to govern the attitudes of the older generation in this sample. This finding should mitigate potential conflicts over issues of intergenerational equity and fairness, both within the family and in public policy.

Middle generation roles and the well-being of men and women.

Sociological literature on gender, work, and families has focused on both conflict and benefits created by combining the spouse, parent, and paid worker roles, whereas research by family gerontologists has focused on stress experienced by those who provide care to frail elderly parents as well as other roles associated with being in the "middle generation." We examine consequences of adding middle generation roles to other major life roles during the middle years. We find that giving help to parents increases men's distress, while giving help to adult children enhances women's well-being. When help to biological parents is examined separately, it is found to increase both men's and women's distress. Women are unaffected by the multiplicity of roles while, for men, there is evidence of both role buffering and strain from conflicting demands. We discuss further directions for research on consequences of roles for well-being.

Informal support and the use of formal services by older Americans.

Older persons' use of formal services was studied in the context of one medium-sized metropolitan area in the Northeast, with a principal focus on the relation between formal service use and informal help. Most services are used by only a minority of older persons. There is some evidence of both compensatory processes (where family support substitutes for formal care) and bridging (where the informal network helps link the older person to services). Service users are distinguished partly by their greater functional disability. Use of some services is affected by indicators of predisposition, such as sociability and age identity. Enabling factors, such as availability of services or their accessibility by the respondent, have little effect.

Predicting the frequency of senior center attendance.

The frequency of senior center attendance was studied using the 1984 Supplement on Aging of the National Health Interview Survey. Unlike previous research, which focused on whether people ever attend a senior center, this study estimates a multinomial logistic regression model to distinguish between persons who rarely, sometimes, and frequently attend. There is evidence that the more frequent users are older, which may indicate difficulty in recruiting new active members. Greater frequency is associated with lower income and lower education but is unrelated to functional disability. The most frequent users are persons who are more socially involved. Finally, those who live in rural areas are more likely to be only occasional users, which may reflect a lack of accessibility or less frequent program availability in those areas.

Locational returns to human capital: minority access to suburban community resources.

The suburbanization of racial and ethnic minorities is analyzed in terms of the locational resources provided by their communities of residence. In suburbs in the New York CMSA, non-Hispanic whites and Asians, on average, live in communities with higher average socioeconomic status, while Hispanics and blacks live in the less desirable suburbs. Models predicting suburban socioeconomic status for each racial/ethnic group show that whites and Hispanics receive consistent returns on income, acculturation, and family status. Asians' locational patterns differ because they are unrelated to measures of acculturation; for blacks, locational outcomes correspond least to any of these human capital characteristics.

Family structure and changes in living arrangements among elderly nonmarried parents.

We used Longitudinal Study of Aging data to investigate change between 1984 and 1986 in living arrangements of older nonmarried parents, focusing on transitions from living alone and living with children to living alone, with children, with others, and institutionalization. Predictors reflect opportunities for coresidence (number and gender of children), resources, needs, and (indirect measures of) attitudes. We find that those with more children are more likely to change from living alone to living with a child. However, number of children does not affect the odds of moving from living with a child to other arrangements (including institutionalization). Gender of children does not affect tendencies to begin coresidence, although there is slight evidence of more movement out of coresidence for those with sons. Findings are interpreted in terms of the influence of adult children's and parents' needs in determining coresidence.

Assimilation and stratification in the homeownership patterns of racial and ethnic groups.

"This study investigates homeownership differences among twelve racial/ethnic groups using the [U.S.] Public Use Sample data (PUMS) of the 1980 census.... The study identifies a number of differences among non-Hispanic whites, blacks, American Indians, and Asian and Hispanic groups in access to homeownership.... For every group there is a strong correspondence between homeownership and various individual-level factors: age, household composition, socioeconomic position and language acculturation. The observed differences in ownership are substantially attenuated when group differences in some of these variables are controlled."

Variations on two themes: racial and ethnic patterns in the attainment of suburban residence.

To investigate racial and ethnic diversity in suburbanization, we draw on two complementary theoretical traditions, which we label "assimilation" and "stratification." Our analytic model is multilevel, and includes variables characterizing individuals, households, and metropolitan contexts. We use it to analyze the determinants of suburban versus central-city residence for 11 racial/ethnic groups. The analysis reveals that family status, socioeconomic, and assimilation variables influence the suburbanization process rather consistently. We take this finding as evidence in favor of the assimilation model. These effects display group variations, however, in a manner predicted by the stratification model. There are also suburbanization differences among metropolitan areas, particularly related to the relative economic status of cities and their suburbs, and between the northeast/north central regions and the south/west. Finally, we conclude that suburbanization is variable across the groups in a way that is not captured by broad categories such as "Asian" or "Hispanic."

Thyrohyoid separation due to penetrating trauma.

We present two cases of neck lacerations resulting from automobile accidents where the victim was thrown through the windshield and suffered thyrohyoid separation. In this lesion, the laryngeal mechanism is intact but detached from the hypopharynx. The prognosis is excellent with early recognition and repair.