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Comparing Populations (comparing + population)

Distribution by Scientific Domains

Life Sciences	75%

Selected Abstracts

Standardized health check data from community-dwelling elderly people: the potential for comparing populations and estimating need

HEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 1 2000
Peter Bath PhD
Abstract The main aim of this study was to compare EASY-Care data obtained during nurse-administered annual health checks in two populations of older people. A secondary aim was to determine whether a standardized assessment system administered as part of routine practice by a trained nurse during the over-75 health check could generate useful information for comparing population health and functional status of community-dwelling-older people. One hundred and seventy-nine elderly people (aged 75 years and over) from the Woodstock ward, Belfast, having relatively high deprivation; and 238 elderly people from south Hampshire, ranging from affluent wards in New Forest to inner city wards, were assessed using the EASY-Care assessment system as part of their annual health check. There was a high response rate to the standardized assessment in both populations (75% and 79%). Compared to people in south Hampshire, the people in Belfast had higher relative risk of having fair/poor self-rated health, and lower relative risk of having good/sufficient accommodation and of having difficulty chewing. People in Belfast had a higher relative risk of being dependent for six of the seven IADL items and for continence of urine, bathing, grooming, use of the stairs and dressing among the ADL items. The results demonstrate the ability of data generated by assessment system to discriminate between populations of older people when used as part of routine practice. Differences in health and functional status may be associated with deprivation. Data collected during the annual health check about the health and functional status of older people could provide a useful adjunct to census and survey data to measure population needs and to support locality planning. [source]

Equivalence of Three Allocation Currencies as Estimates of Reproductive Allocation and Somatic Cost of Reproduction in Pinguicula vulgaris

PLANT BIOLOGY, Issue 4 2007
M. Méndez
Abstract: Which is the most appropriate currency (biomass, energy, water, or some mineral nutrient) for expressing resource allocation in plants has been repeatedly discussed. Researchers need to assess to which extent interindividual, interpopulational, or interspecific comparisons of resource allocation could be affected by the allocation currency chosen. The "currency issue" is relevant to at least three related aspects of resource allocation to reproduction: (a) reproductive allocation (RA), (b) size-dependence of reproductive allocation, and (c) somatic cost of reproduction (SCR). Empirical tests have mostly dealt with the first aspect only. We examined the equivalence of estimates for the three aspects above across three different allocation currencies (dry mass, N, P) in 11 populations of Pinguicula vulgaris. For RA we studied the equivalence of allocation currencies at three scales: among individuals of the same population, between populations of the same species, and among species. Equivalence of currencies in the ranking of RA for individuals within populations was high (Rs 0.43) and did not strongly decrease when comparing populations or species. Excepting for size-dependence of RA, ranking of RA, or SCR between populations was equivalent for biomass and N, but not for P. Our study gives two positive guidelines for empirical plant reproductive ecologists facing the "currency issue": (1) become increasingly concerned about the "currency issue" as you increase the scale of your comparison from individuals to populations to species, and (2) avoid estimating allocation in redundant currencies (biomass and N in our case) and choose preferentially "complementary" currencies that provide a broader view of allocation patterns (biomass and P in our case). [source]

Body condition does not predict immunocompetence of western pond turtles in altered versus natural habitats

ANIMAL CONSERVATION, Issue 3 2010
N. Polo-Cavia
Abstract Many authors have addressed the relationship between body condition and ecological parameters in a wide range of studies, suggesting a better fitness in those individuals with higher values of body condition. However, body size and body condition of individuals can vary significantly at the intraspecific level between geographic locations, which is usually explained by phenotypic plasticity or local adaptation. We suggest that a higher body condition per se might not be a good indicator of physiological health status, particularly when comparing populations inhabiting places with different levels of habitat alteration. We examined two populations of the western pond turtle Emys marmorata in the northern part of California's Central Valley, and found that individuals inhabiting a water pollution control plant located on the valley floor had significantly larger body size and higher body condition than those inhabiting an unaltered natural habitat in the foothills. However, turtles from the water pollution control plant did not show a better health status, estimated by comparisons between two immune system variables: T-cell-mediated immune response and heterophil/lymphocyte ratio. Parameters such as body size and body condition might be misleading indicators of health condition, particularly when they are used to estimate health status of populations from habitats with different levels of alteration. We emphasize the importance of using physiological methods in assessing the conservation state of wildlife populations, rather than relying on biometric indices that might miss important effects of alteration. [source]

Genetic Heterogeneity of Icelanders

ANNALS OF HUMAN GENETICS, Issue 1 2003
E. Árnason
Summary Recently statements have been made about a special ,genetic homogeneity' of the Icelanders that are at variance with earlier work on blood groups and allozymes. To validate these claims an extensive reanalysis was undertaken of mtDNA variation by examining primary data from original sources on 26 European populations. The results show that Icelanders are among the most genetically heterogeneous Europeans by the mean number of nucleotide differences as well as by estimates of , parameters of the neutral theory. The distribution of pairwise differences in general has the same shape as European populations and shows no evidence of bottlenecks of numbers in Iceland. The allelic frequency distribution of Iceland is relatively even with a large number of haplotypes at polymorphic frequencies contrasting with other countries. This is a signature of admixture during the founding or history of Iceland. Assumptions of models used to simulate number of haplotypes at sampling saturation for comparing populations are violated to different degrees by various countries. Anomalies identified in data in previous reports on Icelandic mtDNA variation appear to be due to errors in publicly accessible databases. This study demonstrates the importance of basing analyses on primary data so that errors are not propagated. Claims about special genetic homogeneity of Icelanders are not supported by evidence. [source]