1,720,959 research outputs found
Sexual differences in central arterial wave reflection are evident in prepubescent children
No full textOBJECTIVE: The objective of this study was to examine the influence of sex on central arterial wave reflection in healthy prepubescent children matched for body size and cardiorespiratory fitness.METHODS: Fifty-five healthy children (9.8?±?1.0 years, 44% girls) were recruited. Cardiorespiratory fitness was assessed using a treadmill-based graded exercise test to volitional exhaustion. Pulse wave analysis was used to measure augmentation index (AIx) and central blood pressures.RESULTS: The girls and boys were matched for age, body size and cardiorespiratory fitness. There were no significant differences between sexes for heart rate or central blood pressure parameters. Girls demonstrated a significantly greater AIx than the boys (8.9?±?9.3 vs. 1.9?±?10.8%, P?=?0.015, d?=?0.69).CONCLUSION: Sexual differences in central arterial wave reflection exist prepubescence, independent of stature or cardiorespiratory fitness. Further study is required to elucidate the mechanism(s) explaining this phenomenon and to determine the influence of wave reflections on left ventricular mass during childhood
A randomized controlled trial to assess the effect of self-paced walking on task-specific anxiety in cardiac rehabilitation patients
No full textPurpose: Cardiac rehabilitation can reduce overall anxiety. However, task-specific anxiety is yet to be investigated in the cardiac patient. This study investigates the effect of an outdoor walking intervention (WI) in alleviating the high degree of task-specific anxiety in cardiac patients.Methods: Participants (N = 22, mean age ± SD = 62.0 ± 10.8 years, 9 women), who had experienced a cardiac event and exhibited a moderate to high level of anxiety for outdoor walking (anxiety score ≥ 7 on a modified version of the Hospital Anxiety and Depression Scale), were initially assessed during an incremental shuttle walk test and a self-paced 1-mile walk. Heart rate and the ratings of perceived exertion were monitored during both tests. Participants also completed an exercise self-efficacy (ESE) questionnaire. Following this, participants were randomized to either a 3 sessions per week, 4 weeks, self-paced WI on a predetermined variable topographic course, or to a control group (CG; 30-minute stationary cycling, 3 sessions per week for 4 weeks). Identical assessments (Incremental Shuttle Walk Test, Self-Paced 1-Mile Walk, Hospital Anxiety and Depression Scale, ESE) were used postintervention. The 2 groups were compared for anxiety, ESE, and fitness by analysis of variance.Result: The WI group exhibited a significantly greater decrease in task-specific anxiety (51%; P < .01), increased self-efficacy (6.6%; P < .001) and improved fitness (P < .05) in comparison with CG.Conclusion: This study demonstrated that task familiarization reduced the task-specific anxiety associated with outdoor walking in cardiac patients and, as such, may help in changing exercise behavior patterns in patients undergoing cardiac rehabilitation
The effectiveness of a high-intensity games intervention on improving indices of health in young children
No full textThis study assessed the effectiveness of a 6-week, high-intensity, games-based intervention on physiological and anthropometric indices of health, in normal weight (n = 26; 32.5 ± 8.9 kg) and obese (n = 29; 49.3 ± 8.9 kg) children (n = 32 boys, 23 girls), aged 8–10 years. Children were randomised into an exercise or control group. The exercise group participated in a twice-weekly, 40 min active games intervention, alongside their usual school physical education classes. The control group did not take part in the intervention. Before and after the intervention, participants completed both a maximal and submaximal graded exercise test. The submaximal exercise test comprised of a 6 min, moderate- and 6 min heavy-intensity bout, interspersed with a 5 min recovery. The exercise group demonstrated improvements in maximal oxygen uptake (51.4 ± 8.5 vs 54.3 ± 9.6 ml · kg?1 · min?1) and peak running speed (11.3 ± 1.6 vs 11.9 ± 1.6 km · h?1), and a reduction in the oxygen cost of submaximal exercise between assessments (P < .05). A decrease in waist circumference and increase in muscle mass were observed between assessments for the obese participants randomised to the intervention (both P < .05). This study demonstrates that a short-term, high-intensity games intervention may elicit positive changes in physiological and anthropometric indices of health in normal weight and obese children
The influence of body weight on the pulmonary oxygen uptake kinetics in pre-pubertal children during moderate- and heavy intensity treadmill exercise
No full textTo assess the influence of obesity on the oxygen uptake VO2 kinetics of pre-pubertal children during moderate- and heavy intensity treadmill exercise. We hypothesised that obese (OB) children would demonstrate significantly slower VO2 kinetics than their normal weight (NW) counterparts during moderate- and heavy intensity exercise. 18 OB (9.8 ± 0.5 years; 24.1 ± 2.0 kg m(2)) and 19 NW (9.7 ± 0.5 years; 17.6 ± 1.0 kg m(2)) children completed a graded-exercise test to volitional exhaustion and two submaximal constant work rate treadmill tests at moderate (90 % gas exchange threshold) and heavy (? 40 %) exercise intensities. Bodyweight significantly influenced the VO2 kinetics during both moderate- and heavy exercise intensities (P < 0.05). During moderate intensity exercise, the phase II ? (OB: 30 ± 13 cf. NW: 22 ± 7 s), mean response time (MRT; OB: 35 ± 16 cf. NW: 25 ± 10 s), phase II gain (OB: 156 ± 21 cf. NW: 111 ± 18 mL O2 kg(-1) km(-1)) and oxygen deficit (OB: 0.36 ± 0.11 cf. NW: 0.20 ± 0.06 L) were significantly higher in the OB children (all P < 0.05). During heavy intensity exercise, the ? (OB: 33 ± 9 cf. NW: 27 ± 6 s; P < 0.05) and phase II gain (OB: 212 ± 61 cf. NW: 163 ± 23 mL O2 kg(-1) km(-1); P < 0.05) were similarly higher in the OB children. A slow component was observed in all participants during heavy intensity exercise, but was not influenced by weight status. In conclusion, this study demonstrates that weight status significantly influences the dynamic VO2 response at the onset of treadmill exercise in children and highlights that the deleterious effects of being obese are already manifest pre-puberty
The influence of a six-week, high-intensity games intervention on the pulmonary oxygen uptake kinetics in prepubertal obese and normal-weight children
No full textThe pulmonary oxygen uptake response is deleteriously influenced by obesity in prepubertal children, as evidenced by a slower phase II response. To date, no studies have investigated the ability of an exercise intervention to ameliorate this. The objective of the study was to investigate the influence of a 6-week, high-intensity, games-orientated intervention on the oxygen uptake kinetic response of prepubertal obese and normal-weight children during heavy-intensity exercise. Thirteen normal-weight and 15 obese children participated in a twice-weekly exercise intervention involving repeated bouts of 6-min high-intensity, games-orientated exercises followed by 2 min of recovery. Sixteen normal-weight and 11 obese children served as a control group. At baseline and post-intervention, each participant completed a graded-exercise test to volitional exhaustion and constant work-rate, heavy-intensity exercise. Post-intervention, obese children demonstrated a reduced phase II ? (pre-intervention: 30 ± 8 cf. post-intervention: 24 ± 7 s), mean response time (pre-intervention: 50 ± 10 cf. post-intervention: 38 ± 9 s) and phase II amplitude (pre-intervention: 1.51 ± 0.30 cf. post-intervention: 1.34 ± 0.27 L·min?1). No changes were evident in the normal-weight children. In conclusion, the present findings demonstrate that a 6-week, high-intensity intervention can have a significant positive impact on the dynamic oxygen uptake response of obese prepubertal children
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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