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61.
Most zoos keep comprehensive records, which potentially form a database for use in answering some research questions, such as in veterinary and population management research. They have not, however, been widely used to answer questions about animal behavior and welfare. Here we try to assess the usefulness to behavioral research of two sorts of zoo records (ARKS, the Animal Records Keeping System, and student dissertations held on file) to test the hypothesis that ring-tailed lemurs with a left limb preference experience more negative social lives. We found that, as predicted, lemurs with a left limb preference (LH) received more aggression and were involved in less grooming than nonleft-preferent lemurs (NLH), though the differences were not statistically significant. Contrary to prediction, LH lemurs had fewer reported woundings than NLH lemurs, but again the difference was not statistically significant. We found that the ARKS reports did not contain sufficient quantified and systematic behavioral data for our purposes, although otherwise they provided an excellent context for interpreting results. The student dissertations were also of limited use, primarily because of the small time frame in which they were carried out. Because of these shortcomings we were unable to distinguish whether our inability to find significant effects was due to biological (perhaps hand preference had no consequences for the lemurs) or data reasons. We suggest that closer liaison between zoo research staff, zoo record keepers and academic supervisors could help to improve the usefulness of zoo records for behavioral research. 相似文献
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Pasiakos SM Karl JP Lutz LJ Murphy NE Margolis LM Rood JC Cable SJ Williams KW Young AJ McClung JP 《PloS one》2012,7(2):e31222
Background
Cardiometabolic disease risk in US military recruits and the effects of military training have not been determined. This study examined lifestyle factors and biomarkers associated with cardiometabolic risk in US Army recruits (209; 118 male, 91 female, 23±5 yr) before, during, and after basic combat training (BCT).Methodology/Principal Findings
Anthropometrics; fasting total (TC), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol; triglycerides (TG); glucose; and insulin were measured at baseline and every 3 wks during the 10 wk BCT course. At baseline, 14% of recruits were obese (BMI>30 kg/m2), 27% were cigarette smokers, 37% were sedentary, and 34% reported a family history of cardiometabolic disease. TC was above recommended levels in 8%, LDL in 39%, TG in 5%, and glucose in 8% of recruits, and HDL was below recommended levels in 33% of recruits at baseline. By week 9, TC decreased 8%, LDL 10%, TG 13%, glucose 6% and homeostasis model assessment of insulin resistance (HOMA-IR) 40% in men (P<0.05). In women, TC, LDL, glucose and HOMA-IR were decreased from baseline at weeks 3 and 6 (P<0.05), but were not different from baseline levels at week 9. During BCT, body weight declined in men but not women, while body fat percentage declined in both men and women (P<0.05).Conclusions/Significance
At the start of military service, the prevalence of cardiometabolic risk in US military recruits is comparable to that reported in similar, college-aged populations. Military training appears to be an effective strategy that may mitigate risk in young people through improvements in lipid profiles and glycemic control. 相似文献64.
ABSTRACT: BACKGROUND: The aim of this paper is to examine how breastfeeding is defined for research purposes. DISCUSSION: Current breastfeeding definitions focus on the amount of breast milk an infant receives and do not encompass how a baby is fed. Our concerns are that key variables are not measured when mothers are pumping or expressing their milk and bottle feeding. It seems the breastfeeding relationship is not considered in the definition. CONCLUSION: While we appreciate the implications of full versus partial breastfeeding in research studies, we also believe the method of infant feeding to be significant. Researchers should develop new definitions. 相似文献
65.
Taraban VY Martin S Attfield KE Glennie MJ Elliott T Elewaut D Van Calenbergh S Linclau B Al-Shamkhani A 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(7):4615-4620
Activation of invariant NK T (iNKT) cells with the glycolipid alpha-galactosylceramide promotes CD8(+) cytotoxic T cell responses, a property that has been used to enhance the efficacy of antitumor vaccines. Using chimeric mice, we now show that the adjuvant properties of iNKT cells require that CD40 triggering and Ag presentation to CD8(+) T cells occur on the same APCs. We demonstrate that injection of alpha-galactosylceramide triggers CD70 expression on splenic T cell zone dendritic cells and that this is dependent on CD40 signaling. Importantly, we show that blocking the interaction between CD70 and CD27, its costimulatory receptor on T cells, abrogates the ability of iNKT cells to promote a CD8(+) T cell response and abolishes the efficacy of alpha-GalCer as an adjuvant for antitumor vaccines. These results define a key role for CD70 in linking the innate response of iNKT cells to the activation of CD8(+) T cells. 相似文献
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Stability criteria have recently been developed for coevolutionary Lotka–Volterra systems where individual fitness functions are assumed to be linear in the population state. We extend these criteria as part of a general theory of coevolution (that combines effects of ecology and evolution) based on arbitrary (i.e. nonlinear) fitness functions and a finite number of individual phenotypes. The central role of the stationary density surface where species’ densities are at equilibrium is emphasized. In particular, for monomorphic resident systems, it is shown coevolutionary stability is equivalent to ecological stability combined with evolutionary stability on the stationary density surface. Also discussed is how our theory relates to recent treatments of phenotypic coevolution via adaptive dynamics when there is a continuum of individual phenotypes. 相似文献
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Current techniques for studying phytoplankton physiology in the field, such as measurements of biochemical activities, nutrient addition bioassays, and determination of photosynthetic efficiency, are useful for assessing the physiology of the bulk community but suffer from a lack of specificity. This would be improved by the development of single-cell methods for monitoring in situ physiology. Here we develop and test an antibody-based assay for identifying phosphate stress in the model dinoflagellate Prorocentrum minimum (Pavillard) Schiller. Antiserum was raised against a cell-surface alkaline phosphatase purified from P. minimum. Western screening indicated that the antiserum reacted with phosphate-stressed cells but not nitrate-stressed or phosphate-replete cells in culture. Immunodepletion confirmed the identification of this protein as an alkaline phosphatase. Based on Western blots, the antiserum appeared to be specific for phosphate-regulated proteins in P. minimum because there is no discernible cross-reaction with closely related P. micans. A whole-cell immunofluorescence assay was used to identify phosphate stress in field populations of P. minimum from Narragansett Bay, Rhode Island. The percentage of labeled P. minimum cells in this environment during the summer of 1998 decreased through time as the inorganic phosphate concentration increased. The percentage of antibody-labeled cells significantly correlated with the percentage of ELF-97-labeled cells determined as another single-cell assay of phosphate stress. This is the first antibody-based method developed for monitoring cell-specific physiology in a dinoflagellate, and the method described here may serve as a model for developing similar tools in other species of phytoplankton. 相似文献