Success in sperm competition, occurring whenever females mate with multiple males, is predicted to be influenced by variation in ejaculate quality and interactions among competing sperm. Yet, apart from sperm number, relevant ejaculate characteristics and sperm-sperm interactions are poorly understood, particularly within a multivariate framework and the natural selective environment of the female reproductive tract. Here, we used isogenic lines of Drosophila melanogaster with distinguishable sperm to demonstrate and partition genetic variation in multiple sperm quality and performance traits. Next, by competing males from different lines, we show how rival sperm significantly influence each other's velocity and reveal that males with relatively slow and/or long sperm better displace rival sperm and resist displacement, thus avoiding ejection by the female from her reproductive tract. Finally, we establish fitness consequences of genetic variation in sperm quality and its role in securing a numerical advantage in storage by showing that offspring paternity is determined strictly by the representation of stored, competing sperm. These results provide novel insight into complex postcopulatory processes, illustrate that different ejaculate traits are critical at different biologically relevant time-points, and provide a critical foundation for elucidating the role of postcopulatory sexual selection in trait diversification and speciation.
Erythropoietin is a hypoxia-induced hormone that is essential for normal erythropoiesis. The production of recombinant human erythropoietin (rHuEpo) has revolutionized the treatment of anemia associated with chronic renal failure and chemotherapy, and has been used as prophylaxis to prevent anemia after surgery. The erythropoietin receptor is widely distributed in the cardiovascular system, including endothelial cells, smooth muscle cells and cardiomyocytes. Epo has potentially beneficial effects on the endothelium including anti-apoptotic, mitogenic and angiogenic activities. On the other hand, some reports suggest that rHuEpo may have pro-thrombotic or platelet-activating effects. Hypertension develops in 20-30% of renal patients treated with rHuEpo. Many patients with heart failure have anemia. Despite some potential adverse effects, early studies in heart failure patients with anemia suggest that rHuEpo therapy is safe and effective in reducing left ventricular hypertrophy, enhancing exercise performance and increasing ejection fraction. Further studies are warranted to define the role of rHuEpo in chronic heart failure and other cardiovascular settings.
BackgroundTo determine the effects of participation in Curtin University's Activity, Food and Attitudes Program (CAFAP), a community-based, family-centered behavioural intervention, on the physical activity, sedentary time, and healthy eating behaviours of overweight and obese adolescents.MethodsIn this waitlist controlled clinical trial in Western Australia, adolescents (n = 69, 71% female, mean age 14.1 (SD 1.6) years) and parents completed an 8-week intervention followed by 12 months of telephone and text message support. Assessments were completed at baseline, before beginning the intervention, immediately following the intervention, and at 3-, 6-, and 12- months follow-up. The primary outcomes were physical activity and sedentary time assessed by accelerometers and servings of fruit, vegetables and junk food assessed by 3-day food records.ResultsDuring the intensive 8-week intervention sedentary time decreased by −5.1 min/day/month (95% CI: −11.0, 0.8) which was significantly greater than the rate of change during the waitlist period (p = .014). Moderate physical activity increased by 1.8 min/day/month (95% CI: −0.04, 3.6) during the intervention period, which was significantly greater than the rate of change during the waitlist period (p = .041). Fruit consumption increased during the intervention period (monthly incidence rate ratio (IRR) 1.3, 95% CI: 1.10, 1.56) and junk food consumption decreased (monthly IRR 0.8, 95% CI: 0.74, 0.94) and these changes were different to those seen during the waitlist period (p = .004 and p = .020 respectively).ConclusionsParticipating in CAFAP appeared to have a positive influence on the physical activity, sedentary and healthy eating behaviours of overweight and obese adolescents and many of these changes were maintained for one year following the intensive intervention.Trial RegistrationAustralia and New Zealand Clinical Trials Registry ACTRN12611001187932
Even though entrepreneurial education is quite a new phenomenon in higher education, as a field of inquiry it is one of the most rapidly growing areas of research However there is a wide spread consensus that traditional pedagogical methods of learning alone are insufficient to adequately develop entrepreneurs to deal with the complexities of running and creating innovating business opportunities. There is a wide spread consensus that traditional pedagogical "instructional methods" alone are insufficient to adequately develop entrepreneurs to deal with the complexities of running and creating business opportunities. As a consequence there is a growing need to cultivate innovative ways of thinking and new modes of pedagogy to fully enhance and develop entrepreneurial approaches to education and learning. It is argued that traditional approaches to entrepreneurial education tend to ignore, and not address, the ambiguities and uncertainties which surround the entrepreneurial process. The historical pre-occupation with an individualistic approach to entrepreneurial learning has continued to marginalise and de-value the broader social context in which the entrepreneur functions, (Goss, 2005). Current writing on entrepreneurial learning has shifted attention towards "learning for" as opposed to "learning about" entrepreneurship. The authors adopt a social constructionist perspective which draws recognition to the importance of inter-subjective knowledge exchange as a means of developing entrepreneurial learning. While there are numerous approaches to a social constructionist paradigm, the critical features of the perspective provide the manner by which "we" come to experience the social world. The approach suggests towards developing a pedagogical approach which explores the social processes that constitute entrepreneurial undertakings and thus shifts the focus away from the traditional positivist approaches to entrepreneurial learning. The paper seeks to contribute to a growing need to cultivate innovating ways of thinking, diverse skills and new modes of behaviour to fully enhance and develop entrepreneurial approaches to education. The paper sets out to address this problem by examining the role reflexivity can play in entrepreneurial education, as a method of critiquing what it means to practice as an entrepreneur.
BackgroundAdolescents are considered a hard to reach group and novel approaches are needed to encourage good health. Text messaging interventions have been reported as acceptable to adolescents but there is little evidence regarding the use of text messages with overweight and obese adolescents to support engagement or behavior change after the conclusion of a healthy lifestyle program.ObjectiveThe intent of this study was to explore the opinions of overweight adolescents and their parents regarding the use of text messages as a support during the maintenance period following an intervention.MethodsThis paper reports on the findings from focus groups conducted with adolescents (n=12) and parents (n=13) who had completed an eight-week intensive intervention known as Curtin University’s Activity, Food and Attitudes Program (CAFAP). Focus groups were conducted three months post intensive intervention. Participants were asked about their experiences of the prior three-month maintenance phase during which adolescents had received tri-weekly text messages based on the self-determination theory and goal-setting theory. Participants were asked about the style and content of text messages used as well as how they used the text messages. Data were analyzed using content and thematic analyses.ResultsTwo clear themes emerged from the focus groups relating to (1) what adolescents liked or thought they wanted in a text message to support behavior change, and (2) how they experienced or responded to text messages. Within the “like/want” theme, there were five sub-themes relating to the overall tone of the text, frequency, timing, reference to long-term goals, and inclusion of practical tips. Within the “response to text” theme, there were four sub-themes describing a lack of motivation, barriers to change, feelings of shame, and perceived unfavorable comparison with other adolescents. What adolescents said they wanted in text messages often conflicted with their actual experiences. Parent reports provided a useful secondary view of adolescent experience.ConclusionsThe conflicting views described in this study suggest that overweight and obese adolescents may not know or have the ability to articulate how they would best be supported with text messages during a healthy lifestyle maintenance phase. Further, supporting both engagement and behavior change simultaneously with text messaging may not be possible. Intervention texts should be personalized as much as possible and minimize feelings of guilt and shame in overweight and obese adolescents. Future research with text messaging for overweight and obese adolescents should incorporate clear intervention aims and evaluation methods specifically related to adolescent engagement or behavior change.Trial RegistrationAustralian New Zealand Clinical Trials Registry: ACTRN12611001187932; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12611001187932 (Archived by WebCite at http://www.webcitation.org/6LGSbk8d9).
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