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    Evaluation of the magnesium status in athletics

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    The purpose of this study was to examine the magnesium balance in endurance athletes. Clarification was to be obtained whether the athletes are more frequently magnesium-deficient than non-athletic persons. In addition, a check was made whether dietary factors are responsible for the onset of magnesium deficiency. 50 volunteers with a mean age of 25 years were enrolled in this randomized, prospective study. Based on a cycle ergometry test women with an aerobic-anaerobic threshold above 2.4 W/kg (n=7) and men above 2.6 W/kg (n=18) were assigned to the group of endurance athletes, the remaining 25 subjects formed the control group (8 women and 17 men), The athletes reported training at least 9 hours per week, the subjects in the control group less than 9 hours per week. Since earlier studies had shown that a serum magnesium concentration within the normal range does not necessarily exclude a magnesium deficiency, and magnesium retention can provide more precise information on the magnesium status using a magnesium loading test, the magnesium retention, plasma magnesium concentration, ionized fraction of plasma magnesium, erythrocytic magnesium concentration, renal magnesium excretion and oral magnesium intake were measured. The mean magnesium retention values in the control group measured using the intravenous magnesium loading test were lower than those in the endurance athletes. No differenees were found in the mean values of plasma magnesium concentration ionized fractions of plasma magnesium and erythrocytic magnesium concentration in the two groups, while the endurance trained subjects excreted significantly more magnesium via the kidneys and had a higher oral magnesium intake than the controt group. The study thus confirms that endurance athletes are more frequently magnesium-deficient than persons who do not engage in endurance sports. This deficiency was caused by elevated renal magnesium excretion. Although the athletes' magnesium intake with food was higher, the magnesium quantity consumed did not suffice to maintain a balanced magnesium status

    Evaluation of the magnesium status in athletics

    No full text
    The purpose of this study was to examine the magnesium balance in endurance athletes. Clarification was to be obtained whether the athletes are more frequently magnesium-deficient than non-athletic persons. In addition, a check was made whether dietary factors are responsible for the onset of magnesium deficiency. 50 volunteers with a mean age of 25 years were enrolled in this randomized, prospective study. Based on a cycle ergometry test women with an aerobic-anaerobic threshold above 2.4 W/kg (n=7) and men above 2.6 W/kg (n=18) were assigned to the group of endurance athletes, the remaining 25 subjects formed the control group (8 women and 17 men), The athletes reported training at least 9 hours per week, the subjects in the control group less than 9 hours per week. Since earlier studies had shown that a serum magnesium concentration within the normal range does not necessarily exclude a magnesium deficiency, and magnesium retention can provide more precise information on the magnesium status using a magnesium loading test, the magnesium retention, plasma magnesium concentration, ionized fraction of plasma magnesium, erythrocytic magnesium concentration, renal magnesium excretion and oral magnesium intake were measured. The mean magnesium retention values in the control group measured using the intravenous magnesium loading test were lower than those in the endurance athletes. No differenees were found in the mean values of plasma magnesium concentration ionized fractions of plasma magnesium and erythrocytic magnesium concentration in the two groups, while the endurance trained subjects excreted significantly more magnesium via the kidneys and had a higher oral magnesium intake than the controt group. The study thus confirms that endurance athletes are more frequently magnesium-deficient than persons who do not engage in endurance sports. This deficiency was caused by elevated renal magnesium excretion. Although the athletes' magnesium intake with food was higher, the magnesium quantity consumed did not suffice to maintain a balanced magnesium status

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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