879 resultados para American Academy in Rome


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The frequency of PRRSV corresponding to live vaccines and wild-type was determined in 902 pigs from North-Western Germany submitted for post-mortem examination. Overall, 18.5% of the samples were positive for the EU wild-type virus. EU genotype vaccine virus was detected in 1.3% and the NA genotype vaccine virus in 8.9% of all samples. The detection of the EU vaccine was significantly higher in pigs vaccinated with the corresponding vaccine (OR=9.4). Pigs vaccinated with NA genotype had significantly higher detection chances for the corresponding vaccine virus when compared to non-vaccinated animals (OR=3.34) animals, however, NA vaccine was also frequently detected in non-vaccinated pigs. Concluding, the dynamics of NA genotype vaccine and EU wild-type virus corresponds with studies on PRRSV spread in endemically infected herds. The potential of spontaneous spread of the NA genotype vaccine should be considered in the planning of eradication programs.

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I modeled the cumulative impact of hydroelectric projects with and without commercial fishing weirs and water-control dams on the production, survival to the sea, and potential fecundity of migrating female silver-phase American eels, Anguilla rostrata in the Kennebec River basin, Maine, This river basin has 22 hydroelectric projects, 73 water-control dams, and 15 commercial fishing weir sites. The modeled area included an 8,324 km(2) segment of the drainage area between Merrymeeting Bay and the upper limit of American eel distribution in the basin. One set of input,, (assumed or real values) concerned population structure (Le., population density and sex ratio changes throughout the basin, female length-class distribution, and drainage area between dams), Another set concerned factors influencing survival and potential fecundity of migrating American eels (i.e., pathway sequences through projects, survival rate per project by length-class. and length-fecundity relationship). Under baseline conditions about 402,400 simulated silver female American eels would be produced annually reductions in their numbers due to dams and weirs would reduce the realized fecundity (i.e., the number of eggs produced by all females that survived the migration). Without weirs or water-control dams, about 63% of the simulated silverphase American eels survived their freshwater spawning migration run to the sea when the survival rate at each hydroelectric dam was 9017, 40% survived at 80% survival per dam, and 18% survived at 60% survival per dam. Removing the lowermost hydroelectric dam on the Kennebec River increased survival by 6.0-7.6% for the basin. The efficient commercial weirs reduced survival to the sea to 69-76%( of what it would have been without weirs', regardless of survival rates at hydroelectric dams. Water-control dams had little impact on production in this basin because most were located in the upper reaches of tributaries. Sensitivity analysis led to the conclusion that small changes in population density and female length distribution had greater effects on survival and realized fecundity than similar changes in turbine survival rate. The latter became more important as turbine survival rate decreased. Therefore, it might be more fruitful to determine population distribution in basins of interest than to determine mortality rate at each hydroelectric project.

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Growth histories of yellow-phase American eels Anguilla rostrata collected in four rivers in Maine, were back-calculated from sagittal otolith increments. Our objectives were to first determine whether sexually dimorphic growth rates exist and then compare the growth histories of American eels from four rivers within a geographic region. For female eels, the maximum growth rate was 31.9 +/- 1.7 mm/year at age 8, decreasing to 25.1 +/- 2.9 mm/year at age 14. Males attained a maximum of 29.8 +/- 1.6 min/year at age 3, decreasing to a minimum of 17.9 +/- 1.3 mm/year at age 11. Females grew faster than males after age 4 and had a slower reduction in growth rate with age. These faster growth rates among females were similar in all four rivers. The observed growth rates are not consistent with current life history hypotheses and may indicate an alternative life history strategy. Because female eels benefit from a larger size (i.e., size refuge, increased fecundity, and greater niche breadth), they would benefit from a higher-risk growth strategy that increases growth rate during their earlier years and reduces the amount of time spent in an unfavorable size-class. The tradeoffs (i.e., mortality, developmental rate, pathogen resistance, and longevity) associated with this faster growth rate may not favor the males' life history requirements. Male eels do not achieve the size of females and therefore are not subject to the advantages associated with being larger. Therefore, they may use a risk-averse strategy that maintains submaximum growth rates to obtain the minimum size necessary to mature and complete the spawning migration while reducing the adverse affects of faster growth rates. We postulate that, in eels, intrinsic growth rates should be considered a life history trait that has evolved to meet the life history requirements of each sex.

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The focus of the study was to identify variables that African American women who delivered at a teaching hospital in Houston, Harris County, Texas, between January 12, 1998 and April 24, 1998 perceived to prevent them from receiving adequate prenatal care. The research was based on Aday and Andersen's Framework for the Study of Access to Medical Care. A self-administered questionnaire, using realized and potential access indicators, was developed and administered to 161 African American patients at the study hospital. ^ The objectives of the study were (1) to describe the demographic characteristics of African American women who delivered at a large urban teaching hospital between January 12, 1998 and April 24, 1998; and to determine the relationships between (2) predisposing factors such as age, race, educational level, marital status, family structure, social support and attitude toward prenatal care and prenatal care utilization; (3) enabling factors such as income, employment, insurance status, transportation, appointment, and regular source of care; (4) need factors such as perceived health status, number of past pregnancies, pregnancy occurrence; and (5) the relative importance of predisposing, enabling and need factors as predictors of utilization of prenatal care. The indicators of prenatal care utilization examined included the trimester in which the women initiated prenatal care, number of visits, and numbers and types of services received during pregnancy. Barriers cited included low income and inadequate insurance coverage, problems of transportation and child care, unawareness of pregnancy, delays in the scheduling of appointments, and having too many other problems. ^ The results of the study have implications for well-defined public health promotion campaigns, social support system enhancement, and appointment scheduling reform with an emphasis on prenatal care. ^

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African Americans make up 12.3% of the population but account for over half of the new HIV cases and 39% of the AIDS cases in 2003 (Centers for Disease Control and Prevention [CDC], 2003). African American women in particular accounted for 64% of these cases of HIV and 60% of the AIDS cases (Leigh & Huff, 2003). This study contributed to the knowledge about the disclosure process of women living with HIV/AIDS by documenting the relationship between social support and the disclosure process in the African American HIV/AIDS population.^ The study aims were to: (1) discuss the participants' self concept of support; (2) describe the common characteristics of the disclosure process; and (3) evaluate the common characteristics of support sought in a potential disclosure source. The ethnographic qualitative methodology was utilized to elicit participant narratives of HIV disclosure and social support. The researcher utilized a key informant interview methodology building on existing social and organizational relationships (Krueger, 1994) to gain access to the population. ^ Semi-structured interviews are a widely used and accepted qualitative research method for use with hard to reach populations and sensitive topics. Ten participants completed a 45 to 60 minute, one on one semi-structured interview covering social support and disclosure variables. Inclusion and exclusion criteria included: (1) self identified as a person living with HIV/AIDS; (2) African American); (3) female; (4) age 18-64 years old, (5) residence in Houston or surrounding counties.^ Themes generated from the interviews were (1) nondisclosure, (2) experiences with disclosure, (3) timing, (4) disclosure sources, and (5) coping. The themes suggest African American women living with HIV/AIDS come from different lifestyles but share similar experiences. Women utilize different strategies such as deciphering whom to trust and determining how much information to divulge in order to protect themselves or others.^ Although the sample group was small for this study, the results inform us about the various experiences each woman goes through as it relates to social support and disclosure and that each woman has to customize her response to the type of support she is receiving and her personal attitude about her disease.^

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Differential access to health care services has been observed among various groups in the United States. Minorities and low-income groups have been especially notable in their decreased access to regular providers of care. This is believed by many to account for some of the higher rates of morbidity and mortality and shorter life expectancies of these groups.^ This research delineated the factors associated with health care access for a particular subset of a minority group, the Mexican American elderly in Texas. Hospital admission and evidence of a regular source of medical care and dental care were chosen as the indicators of access to health care.^ This study analyzed survey interview data from the Texas Study on Aging, 1976. The 597 Mexican American elderly included in this study were representative of the non-institutionalized Mexican American elderly in Texas aged 55 or older.^ The results indicate that hospital admission is not a question of discretion and that common barriers to access, such as income, health insurance, and distance to the nearest facility, are not important in determining hospital admission. Mexican American elderly who need to be hospitalized, as indicated by self-perception of health and disability days, will be hospitalized.^ The results also indicate that having a regular source of medical care is influenced by many factors, some mutable and some immutable. The well-established and immutable factors of age, sex, and need were confirmed. However, the mutable factors such as area of residence and income were also found to have a significant influence. Mexican American elderly living in urban areas had significantly less access to a regular source of medical care as did those who were near the poverty level (as opposed to those who were well below the poverty level). In general, persons claiming a regular source of medical care were more likely to be women, persons who had many health needs, were near the poverty level, lived in urban areas, and had extensive social support systems.^ Persons claiming a regular source of dental care tended to be more advantaged. They had more education, a more extensive informal social support network, higher income, and were generally younger and in better health. They were also more likely to have private health insurance. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UMI ^

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Purpose of the Study: This study evaluated the prevalence of periodontal disease between Mexican American elderly and European American elderly residing in three socio-economically distinct neighborhoods in San Antonio, Texas. ^ Study Group: Subjects for the original protocol were participants of the Oral Health: San Antonio Longitudinal Study of Aging (OH: SALSA), which began with National Institutes of Health (NIH) funding in 1993 (M.J. Saunders, PI). The cohort in the study was the individuals who had been enrolled in Phases I and III of the San Antonio Heart Study (SAHS). This SAHS/SALSA sample is a community-based probability sample of Mexican American and European American residents from three socio-economically distinct San Antonio neighborhoods: low-income barrio, middle-income transitional, and upper-income suburban. The OH: SALSA cohort was established between July 1993 and May 1998 by sampling two subsets of the San Antonio Heart Study (SAHS) cohort. These subsets included the San Antonio Longitudinal Study of Aging (SALSA) cohort, comprised of the oldest members of the SAHS (age 65+ yrs. old), and a younger set of controls (age 35-64 yrs. old) sampled from the remainder of the SAHS cohort. ^ Methods: The study used simple descriptive statistics to describe the sociodemographic characteristics and periodontal disease indicators of the OH: SALSA participants. Means and standard deviations were used to summarize continuous measures. Proportions were used to summarize categorical measures. Simple m x n chi square statistics was used to compare ethnic differences. A multivariable ordered logit regression was used to estimate the prevalence of periodontal disease and test ethnic group and neighborhood differences in the prevalence of periodontal disease. A multivariable model adjustment for socio-economic status (income and education), gender, and age (treated as confounders) was applied. ^ Summary: In the unadjusted and adjusted model, Mexican American elderly demonstrated the greatest prevalence for periodontitis, p < 0.05. Mexican American elderly in barrio neighborhoods demonstrated the greatest prevalence for severe periodontitis, with unadjusted prevalence rates of 31.7%, 22.3%, and 22.4% for Mexican American elderly barrio, transitional, and suburban neighborhoods, respectively. Also, Mexican American elderly had adjusted prevalence rates of 29.4%, 23.7%, and 20.4% for barrio, transitional, and suburban neighborhoods, respectively. ^ Conclusion: This study indicates that the prevalence of periodontal disease is an important oral health issue among the Mexican American elderly. The results suggest that the socioeconomic status of the residential neighborhood increased the risk for severe periodontal disease among the Mexican American elderly when compared to European American elderly. A viable approach to recognizing oral health disparities in our growing population of Mexican American elderly is imperative for the provision of special care programs that will help increase the quality of care in this minority population.^