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Adult Age Groups (adult + age_groups)
Selected AbstractsEstimating natal dispersal movement rates of female European ducks with multistate modellingJOURNAL OF ANIMAL ECOLOGY, Issue 6 2003Peter Blums Summary 1We used up to 34 years of capture,recapture data from about 22 100 new releases of day-old female ducklings and multistate modelling to test predictions about the influence of environmental, habitat and management factors on natal dispersal probability of three species of ducks within the Engure Marsh, Latvia. 2The mean natal dispersal distances were very similar (c. 0·6,0·7 km) for all three species and were on average 2·7 times greater than breeding dispersal distances recorded within the same study system. 3We were unable to confirm the kinship hypothesis and found no evidence that young first-nesting females nested closer to their relatives (either mother or sister) than to the natal nest. 4Young female northern shovelers, like adults, moved from small islands to the large island when water level was high and vice versa when water level was low before the construction of elevated small islands. Movement probabilities between the two strata were much higher for young shovelers than adults, suggesting that young birds had not yet developed strong fidelity to the natal site. Movements of young female tufted ducks, unlike those of shovelers, were not dependent on water level fluctuations and reflected substantial flexibility in choice of first nesting sites. 5Data for young birds supported our earlier conclusion that common pochard nesting habitats in black-headed gull colonies were saturated during the entire study period. Young females, like the two adult age groups, moved into and out of colonies with similar probability. Fidelity probability of female pochards to each stratum increased with age, being the lowest (0·62) for young (DK) females, intermediate (0·78) for yearlings (SY) and the highest (0·84) for adult (ASY) females. 6Young female tufted ducks, like adults, showed higher probabilities of moving from islands to emergent marshes when water levels were higher both before and after habitat management. The relationship between the spring water levels and movement was much weaker for young females than for adults. 7Young female diving ducks exhibited much stronger (compared to adults) asymmetric movement with respect to proximity to water, with higher movement probabilities to near-water locations than away from these locations. 8Local survival of day-old ducklings during the first year of life was time-specific and very low (means for different strata/states 0·01,0·08) because of high rates of emigration and prefledging mortality. [source] Isotopic evidence of dietary variations and weaning practices in the Gaya cemetery at Yeanri, Gimhae, South KoreaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Kyungcheol Choy Abstract Stable carbon and nitrogen isotope analyses were conducted to investigate dietary variation in human skeletons (n = 109) from the Gaya cemetery at Yeanri located near Gimhae City, South Korea. The cemetery contained three distinct grave types dating to 4th,7th century AD. The main purposes of this research were to reconstruct palaeodiet in the Gaya population and to explore correlations between stable isotope compositions and burial types, inferred age, and sex of these individuals. The isotopic data indicate that the people at Yeanri consumed a predominantly C3 -based terrestrial diet supplemented with freshwater and/or marine resources. The comparison of isotopic results reveals significant differences in ,13C values among three adult burial types (wood-cist coffin: ,18.5 ± 0.5,, stone-cist coffin: ,18.1 ± 0.6,, mausoleum: ,17.8 ± 0.9,). Males in wood-cist and stone-cist coffins have relatively more elevated mean ,13C and ,15N values than females. The isotopic ratios from the two adult age groups (21,40 years and 40,60 years) indicate that there was no significant dietary change in individuals with age. The isotope data from the infants and children suggest the weaning was a gradual process that was completed between 3 and 4 years of age in the Gaya population. This evidence indicates that the dietary variations within the cemetery reflect social status, sex, and childhood consumption patterns. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Isotopic evidence for age-related variation in diet from Isola Sacra, ItalyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2005Tracy L. Prowse Abstract This study examines collagen (N = 105) and apatite (N = 65) data from an Imperial Roman skeletal sample from the necropolis of Isola Sacra (Rome, Italy). This paper explores correlations between the isotopic composition of bone samples and the inferred age and sex of these individuals (aged 5,45+ years). The collagen of males, and older individuals in general, was significantly enriched in 15N but not 13C. Bone carbonate was somewhat depleted in 13C in some older individuals, suggesting increased consumption of olive oil and possibly wine. Subadults (>5 years) in the sample appear to have consumed an almost exclusively terrestrial diet. This study demonstrates a clear trend in dietary patterns between adult age groups, as well as between adults and children within a population. Am J Phys Anthropol 128:2-13, 2005. © 2005 Wiley-Liss, Inc. [source] Significance of Abnormal Q Waves in the Electrocardiograms of Adults Less than 40 Years OldANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2006Rex N. MacAlpin M.D. Background: Abnormal Q waves (AQW) in the electrocardiogram are commonly ascribed to underlying myocardial infarction (MI). As an imperfectly specific sign of MI, the usefulness of AQW in identifying MI depends on its incidence in the population studied. Methods: Eighty-two subjects under 40 years of age with AQW were compared with 82 subjects from the same institution aged ,40 years with similar AQW to determine the presence or absence of cardiac disease or MI. Results: Cardiac disease was present in 90.2% and 92.7% of the younger and older subjects, respectively, whereas MI was present in only 15.9% of younger subjects and in 68.3% of older subjects. Etiologies of cardiac disease differed between younger and older subjects. Some types of AQW were more useful than others in ruling MI in or out. Conclusions: AQW were a strong indicator of organic heart disease in both adult age groups, but their utility to indicate MI was age-dependent. In the population studied, MI was present in only a small minority of subjects under 40 years of age with AQW, but was usually present in older subjects with similar AQW. [source] Comparing children and adults with synovial sarcoma in the Surveillance, Epidemiology, and End Results program, 1983 to 2005CANCER, Issue 15 2009An analysis of 1268 patients Abstract BACKGROUND: Synovial sarcoma (SS) is a typical soft tissue sarcoma subtype crosswise between the pediatric and the adult age groups. Less satisfactory overall outcome has been recorded in adult series. METHODS: This study compares clinical features and outcomes of SS across the different age groups, by analyzing 1268 cases, 213 children/adolescents (,18 years) and 1055 adults, registered in the Surveillance, Epidemiology, and End Results (SEER) 17 database from 1983 to 2005. Cancer-specific survival estimates were compared with univariate and multivariate models. RESULTS: No major differences in stage distribution (localized, regional, and distant stage) were observed comparing the 2 age groups. The estimated 5-year cancer-specific survival was 83% for children/adolescents and 62% for adults (P < .001). Female sex, nonblack race, tumors located in the extremities, localized tumors, and tumors <5 cm in size were associated with better survival. In multivariate analysis, adult patients had significantly higher mortality rates than children after adjusting for other variables. CONCLUSIONS: Children and adults with SS have a similar clinical presentation but a dissimilar outcome, suggesting that factors other than unfavorable clinical features might be involved in the unsatisfactory outcome of adult SS patients. It remains to be ascertained whether this difference is related to biological variables or to historically different treatment approaches adopted in pediatric versus adult patients. Cancer 2009. © 2009 American Cancer Society. [source] | |||||||||||||