135 research outputs found
Investigation of the role of selenium in the nutrition and physiology of neural tissues of chickens and turkeys
Endogenous selenium concentrations in selected tissue of chickens, turkeys, and coturni
Sex ratio and maternal rank in wild spider monkeys: when daughters disperse
Data from a long-term field study of the spider monkey, Ateles paniscus , in Peru indicate that a strongly female-biased sex ratio exists from birth in this population. Of 46 infants born between July 1981 and June 1986, 12 were male, 32 were female and 2 were of undetermined sex. This effect is consistent between years as well, with more females than males born in each year of the study (Table 1). This bias is driven by the fact that low-ranking females produce daughters almost exclusively, while high-ranking females bias their investment somewhat less strongly towards sons (Table 2). The unusual pattern of female-biased maternal investment observed in this population of Ateles probably occurs for a combination of the following reasons: (1) maternal investment in individual male offspring is somewhat greater than in individual female offspring; (2) males remain with their natal groups, and the sons of high-ranking females are likely to be competitively superior to the sons of low-ranking females; (3) males compete for mates, and only the one or two most dominant males within a community are likely to achieve significant reproductive success. Two possible mechanisms of sex-ratio adjustment and the evidence for each are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46880/1/265_2004_Article_BF00302985.pd
Astro-WISE: Chaining to the Universe
The recent explosion of recorded digital data and its processed derivatives
threatens to overwhelm researchers when analysing their experimental data or
when looking up data items in archives and file systems. While current hardware
developments allow to acquire, process and store 100s of terabytes of data at
the cost of a modern sports car, the software systems to handle these data are
lagging behind. This general problem is recognized and addressed by various
scientific communities, e.g., DATAGRID/EGEE federates compute and storage power
over the high-energy physical community, while the astronomical community is
building an Internet geared Virtual Observatory, connecting archival data.
These large projects either focus on a specific distribution aspect or aim to
connect many sub-communities and have a relatively long trajectory for setting
standards and a common layer. Here, we report "first light" of a very different
solution to the problem initiated by a smaller astronomical IT community. It
provides the abstract "scientific information layer" which integrates
distributed scientific analysis with distributed processing and federated
archiving and publishing. By designing new abstractions and mixing in old ones,
a Science Information System with fully scalable cornerstones has been
achieved, transforming data systems into knowledge systems. This break-through
is facilitated by the full end-to-end linking of all dependent data items,
which allows full backward chaining from the observer/researcher to the
experiment. Key is the notion that information is intrinsic in nature and thus
is the data acquired by a scientific experiment. The new abstraction is that
software systems guide the user to that intrinsic information by forcing full
backward and forward chaining in the data modelling.Comment: To be published in ADASS XVI ASP Conference Series, 2006, R. Shaw, F.
Hill and D. Bell, ed
Best Practices for Implementing Team-Based Learning in Pharmacy Education
Colleges and schools of pharmacy are incorporating more team-based learning (TBL) into their curriculum. Published resources are available to assist instructors with implementing TBL and describing it in the health professions literature. The 7 core elements include: team formation, readiness assurance, immediate feedback, sequencing of in-class problem solving, the 4 âSâ structure for developing team application exercises (significant problem, same problem, specific answer choice, simultaneous reporting), incentive structure, and peer evaluation. This paper summarizes best practices related to implementation of TBL in pharmacy education, including courses taught using teaching teams
Menstrual cycle regularity and length across the reproductive lifespan and risk of cardiovascular disease
Importance: Menstrual cycle characteristics may be associated with an increased risk of cardiovascular disease (CVD). However, existing studies are limited, and few have explored the mediating role of established CVD risk factors.
Objective: To explore the associations of menstrual cycle characteristics across the reproductive lifespan with the risk of CVD and to what extent these associations were mediated by hypercholesterolemia, chronic hypertension, and type 2 diabetes.
Design, Setting, and Participants: This cohort study prospectively followed Nursesâ Health Study II participants between 1993 and 2017 who reported menstrual cycle regularity and length for ages 14 to 17 years and 18 to 22 years at enrollment in 1989 and updated current cycle characteristics in 1993 (at ages 29 to 46 years). Data analysis was performed from October 1, 2019, to January 1, 2022.
Exposures: Menstrual cycle regularity and length across the reproductive lifespan.
Main Outcomes and Measures: Incident CVD events of interest, including fatal and nonfatal coronary heart disease (CHD; myocardial infarction [MI] or coronary revascularization) and stroke.
Results: A total of 80âŻ630 Nursesâ Health Study II participants were included in the analysis, with a mean (SD) age of 37.7 (4.6) years and body mass index of 25.1 (5.6) at baseline. Over 24 years of prospective follow-up, 1816 women developed their first CVD event. Multivariable Cox proportional hazards models showed that, compared with women reporting very regular cycles at the same ages, women who had irregular cycles or no periods at ages 14 to 17, 18 to 22, or 29 to 46 years had hazard ratios for CVD of 1.15 (95% CI, 0.99-1.34), 1.36 (95% CI, 1.06-1.75), and 1.40 (95% CI, 1.14-1.71), respectively. Similarly, compared with women reporting a cycle length of 26 to 31 days, women reporting a cycle length 40 days or more or a cycle too irregular to estimate from ages 18 to 22 or 29 to 46 years had hazard ratios for CVD of 1.44 (95% CI, 1.13-1.84) and 1.30 (95% CI, 1.09-1.57), respectively. Mediation analyses showed that subsequent development of hypercholesteremia, chronic hypertension, and type 2 diabetes only explained 5.4% to 13.5% of the observed associations.
Conclusions and Relevance: In this cohort study, both irregular and long menstrual cycles were associated with increased rates of CVD, which persisted even after accounting for subsequently established CVD risk factors
- âŠ