1,720,985 research outputs found
Phenotyping exercise limitation in chronic obstructive pulmonary disease to enhance exercise prescription
No full textIntroduction: Phenotyping patients with COPD according to their specific exercise limitation could be important to enhancing our understanding of the integrative physiological responses that limit exercise and how to optimize aerobic exercise prescription for pulmonary rehabilitation. Three studies were performed to identify distinct phenotypes of exercise limitation in COPD based on the ventilatory, cardiovascular and metabolic responses during incremental exercise. Differences in the physiological factors governing submaximal exercise tolerance in each phenotype were also assessed to accurately predict exercise tolerance at two novel indices of sustainable intensity; the highest workload that could be sustained for 30-minutes (critical power 30 [CP30]) and maximal dyspnea steady-state (MDSS).
Methodology: Study 1: Ninety-five COPD patients performed an incremental cardiopulmonary exercise test to assess the physiological exercise responses associated with three different phenotypes of exercise limitation. Study 2: Thirty patients with a ventilatory, cardiovascular or combined (ventilatory and cardiovascular) phenotype performed three constant load exercise tests (CLTs) to determine the individual power-duration relationships and calculate critical power and CP30. An exercise session was performed at CP30. Study 3: In twenty-three patients with different exercise limitation phenotypes, the workload associate with MDSS was calculated from the individual dyspnea responses during the CLTs. A verification trial was performed at MDSS.
Results and Conclusion: Study 1 demonstrated that patients with a ventilatory, cardiovascular or combined exercise limitation phenotype have distinct physiological responses to incremental exercise, that are not solely dependent on FEV₁. Study 2 found that patients with a cardiovascular or combined phenotype could sustain continuous exercise for 30-minutes at a higher workload and blood lactate concentration while maintaining a lower end-expiratory lung volume compared to the ventilatory phenotype. Study 3 confirmed that MDSS can be successfully predicted in COPD but found that MDSS was more applicable to the ventilatory phenotype, supporting that dyspnea may not be the primary limiting symptom in all patients with a cardiovascular or combined phenotype. These results demonstrate the importance of classifying patients with COPD according to their exercise limitation phenotype. These phenotypes may be clinically relevant and can be used to develop innovative methods to optimize exercise prescription for rehabilitative purposes.Health and Social Development, Faculty of (Okanagan)Health and Exercise Sciences, School of (Okanagan)Graduat
Intermittent modulation of exercise and recovery for cardiovagal conditioning
No full textA well-prescribed exercise program can yield significant health and fitness benefits, but excessive training loads can lead to physiologic disturbances and autonomic imbalance. Strategic modulation of exercise and recovery may condition the ANS to recover and adapt more effectively. This research explores novel, accessible methods of within-session exercise-recovery modulation to accelerate cardiovagal withdrawal and reactivation and preserve autonomic balance throughout training. This approach aims to improve health and fitness outcomes while minimizing the risks associated with high workload training.
Study #1 investigated the effects of supine recovery within a high-intensity interval training session, finding that supine recovery accelerates the return of vagal tone and enhances vagal modulation 24hrs post-exercise compared to standing recovery. This suggests that within-session supine recovery may be a novel strategy for attenuating autonomic imbalance, enhancing recovery, and promoting physiological readiness. Study #2 explored the effects of different frequencies of exercise-recovery pattern, finding that high-frequency intermittent modulation improved post-exercise recovery of heart rate and heart rate variability compared to moderate-intensity continuous and low-frequency intermittent training. This indicates that the degree of intermittence influences exercise responses independent of intensity and highlights the potential of intermittent training to reduce internal physiological load and modulate cardiovagal activity. Study #3 examined the chronic modulation of vagal withdrawal and reactivation in recreational endurance athletes, finding that two-weeks of incorporating intermittent recovery bouts into habitual training significantly improved measures of cardiovagal status without compromising fitness. This suggests that intermittent modulations within regular endurance training can enhance cardiovagal conditioning and reduce physiological perturbation from training without a loss of fitness.
Given the prevalence of autonomic imbalance in health, fitness, and performance contexts, strategies to improve cardiovagal status are needed. This dissertation provides a multifaceted examination of how training-based methods of vagal stimulation can be employed to improve cardioautonomic function. Strategic modulation of exercise and recovery can leverage parasympathetic plasticity to enhance physiological recovery, autonomic balance, adaptability, performance readiness, and cardiovascular health. Data from this research suggests that strategies increasing modulation amplitude or frequency can enhance vagal tone and reactivation, promoting positive autonomic adaptation while maintaining fitness.Health and Social Development, Faculty of (Okanagan)Health and Exercise Sciences, School of (Okanagan)Graduat
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
The effect of exercise intensity on airway and systemic inflammation in patients with copd
No full textBibliography: p. 94-10
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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