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51.
This study identifies lessons learned from a collaboration between a child telephone helpline and sexual and reproductive health and rights (SRHR) organisations in Senegal established in the context of an SRHR programme for young people. We assessed how helpline operators are equipped to address sexual health and rights issues with young people, what the relevant skills of operators are, and to what extent referral to sexual and reproductive health (SRH) service providers took place. A documentary review, a vignette study and interviews with six key informants and all seven operators took place. The collaboration led to promising initiatives, such as the provision of SRH training, the exchange of staff, referral to SRH service providers. However, the counselling advice provided by operators was not always in line with the rights-based approach and responses were influenced by underlying norms concerning young people’s sexuality. Additionally, concerns about confidentiality were noted. The collaboration was an innovative attempt to respond to young people’s limited access to SRHR information and services but there is a need for more in-depth training of helpline operator’s skills and the development of a standardised rights-based counselling manual.  相似文献   
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Both radiant and forced convective heat flow were measured for a prototype rowing headgear and white and black cotton caps. The measurements were performed on a thermal manikin headform at a wind speed of 4.0 m . s(-1) (s = 0.1) in a climate chamber at 22.0 degrees C (s = 0.05), with and without radiant heat flow from a heat lamp, coming from either directly above (90 degrees ) or from above at an angle of 55 degrees . The effects of hair were studied by repeating selected measurements with a wig. All headgear reduced the radiant heat gain compared with the nude headform: about 80% for the caps and 95% for the prototype rowing headgear (P < 0.01). Forced convective heat loss was reduced more by the caps (36%) than by the prototype rowing headgear (9%) (P < 0.01). The radiant heat gain contributed maximally 13% to the net heat transfer, with or without headgear, showing that forced convective heat loss is the dominant heat transfer parameter under the chosen conditions. The results of the headgear - wig combinations were qualitatively similar, with lower absolute heat transfer.  相似文献   
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The aim of this study was to investigate differences in joint power generation between well-trained adult athletes and young sprinters from block clearance to initial contact of second stance. Eleven under 16 (U16) and 18 under 18 (U18) promising sprinters executed an explosive start action. Fourteen well-trained adult sprinters completed the exact same protocol. All athletes were equipped with 74 spherical reflective markers, while an opto-electronic motion analysis system consisting of 12 infrared cameras (250 Hz, MX3, Vicon, Oxford Metrics, UK) and 2 Kistler force plates (1,000 Hz) was used to collect the three-dimensional marker trajectories and ground reaction forces (Nexus, Vicon). Three-dimensional kinematics, kinetics, and power were calculated (Opensim) and time normalised from the first action after gunshot until initial contact of second stance after block clearance. This study showed that adult athletes rely on higher knee power generation during the first stance to induce longer step length and therefore higher velocity. In younger athletes, power generation of hip was more dominant.  相似文献   
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Tracking and explaining physical activity in young adults was investigated in a 7-year longitudinal design. From a representative sample of 980 respondents at baseline (M age = 21 years), 172 respondents, comprising 18% of the original sample, completed psychosocial questionnaires and were interviewed at home to assess their level of physical activity at follow-up. Psychosocial variables were grouped into four groups: social variables, self-efficacy, perceived benefits, and perceived barriers. Drop-out analyses showed no major differences between the baseline and follow-up samples. The aims of the present study were: (a) to investigate tracking in physical activity and psychosocial determinants over a 7-year period, and (b) to examine baseline determinants and change in determinants in predicting physical activity change in men and women. No significant tracking of physical activity level was found for men. For women, moderate tracking scores were found for total energy expenditure and moderate-intensity energy expenditure (r = .34 and .41, respectively). There was higher tracking in psychosocial determinants than in physical activity. Relatively high tracking scores for perceived benefits and barriers suggest that cognitions related to physical activity are more stable than the behavior itself. Although baseline psychosocial variables were poor predictors of physical activity change, determinants'change scores accounted for 16-19% of the variance in physical activity in men and 7-24% in women. Significant predictors were different for men and women. Present results can inform the design of physical activity interventions for these populations.  相似文献   
58.
In this study the perception of psychological needs and motivation in a student-centred and a teacher-centred learning environment are compared, using Self Determination Theory as a framework. The self-report Intrinsic Motivation Inventory was completed by 230 students (mean age 16.1 years) in pre-vocational secondary education. School records on absenteeism and achievement were also analysed. As predicted, multi-level analyses showed that students in the student-centred learning environment reported higher levels of perceived autonomy, competence, relatedness and motivation, measured by pleasure and effort. Furthermore, boys were less absent. Achievement shows no differences. These results suggest that a student-centred form of learning can be more beneficial for students' motivation if granted autonomy is embedded in a supportive environment.  相似文献   
59.
Abstract

Both radiant and forced convective heat flow were measured for a prototype rowing headgear and white and black cotton caps. The measurements were performed on a thermal manikin headform at a wind speed of 4.0 m · s?1 (s = 0.1) in a climate chamber at 22.0°C (s = 0.05), with and without radiant heat flow from a heat lamp, coming from either directly above (90°) or from above at an angle of 55°. The effects of hair were studied by repeating selected measurements with a wig. All headgear reduced the radiant heat gain compared with the nude headform: about 80% for the caps and 95% for the prototype rowing headgear (P < 0.01). Forced convective heat loss was reduced more by the caps (36%) than by the prototype rowing headgear (9%) (P < 0.01). The radiant heat gain contributed maximally 13% to the net heat transfer, with or without headgear, showing that forced convective heat loss is the dominant heat transfer parameter under the chosen conditions. The results of the headgear – wig combinations were qualitatively similar, with lower absolute heat transfer.  相似文献   
60.
Abstract

We hypothesized that imagery training would improve the fast onset of neuromuscular activation and thereby fast knee extensor isometric torque development. Forty young healthy participants, not involved in strength training, were assigned to one of four groups: physical training, imagery training, placebo training or control. The three training groups had three 15 min sessions per week for 4 weeks, with a 90° knee angle but were tested also at 120°. At 90° knee angle, maximal torque increased (~8%) similarly in all three training groups. The torque–time integral (contractile impulse) over the first 40 ms after torque onset (TTI40) increased (P < 0.05) after physical training (by ~100%), but only at 90°. This increase was significantly different from the delta values (change pre to post) in the control and placebo groups, whereas delta values in the imagery group were similar to those in the placebo group. The increases in TTI40 following physical training were related (r 2 = 0.81, P < 0.05) to significant increases of knee extensor rectified surface EMG at torque onset (EMG40). In conclusion, only physical training led to a knee angle specific increase of contractile impulse that was significantly different from placebo and controls and that was related to improved onset of neuromuscular activation.  相似文献   
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