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    Assessment of the peripheral hearing system of sport divers

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    Objective: To investigate the effect of regular scuba diving on the hearing thresholds of sport divers who have no history of noise exposure or ear-related accidents. Comprehensive topographic examination of the peripheral hearing system of sport divers. Design: Cross-sectional study. Settings: General sport diving community. Participants: 81 sport divers with a mean of 300 dives each were compared to a control group of 81 non-divers. Main outcome measure: Participants were classified into three age groups. Examination included microscopic otoscopy, tympanometry, pure-tone audiometry (PTA) including air and bone conduction, speech audiometry and otoacoustic emissions (OAE). Results: PTA suggested significant differences of the hearing thresholds at several frequencies between sport divers and non-divers in all age groups, although a Bonferroni correction for multiple testing was applied. Interestingly, the results were contradictory. Divers obtained better hearing results in air conduction, whereas non-divers showed better results in bone conduction. Speech audiometry and OAE did not reveal significant differences. Conclusion: There are no published studies of the peripheral cochlear system of divers that have used a combination of PTA, speech audiometry and OAE. All studies suggesting hearing impairment in divers were based on PTA and might have been influenced by a lack of accuracy of PTA. Our results suggest that diving does not adversely affect the hearing system of sport divers. A thorough test battery of audiological methods implying PTA, speech audiometry and OAE may contribute to offer more reliable results to answer the question of whether commercial or military divers are at higher risk for hearing detonation

    Assessment of the central hearing system of sport divers

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    Objective: To investigate the effect of regular scuba diving on central processing sequences of sport divers who have no history of noise exposure or ear-related accidents using a comprehensive topographic examination of the central hearing system. Design: Cross-sectional controlled comparison study Settings: General sports diving community Participants: 81 sport divers with a mean of 300 dives each were compared with a control group of 81 non-divers. Main outcome measure: The participants were classified into three age groups. Hearing test results were combined for both ears. Examination included brainstem evoked response audiometry (BERA), cortical evoked response audiometry (CERA) and dichotic listening tests to screen for retrocochlear and central hearing disorders. Testing of brainstem latencies was performed in a gender-dependent manner. Results: BERA showed a pathological extension of the I-V-latency in one diver. Magnetic tomographic imaging ruled out brainstem lesions. No reason for the measured latency could be detected. All other latencies (I-III. III-V and I-V) in both gender groups were within normal limits. No statistically significant differences between divers and non-divers could be detected. Dichotic listening showed no clinical abnormalities in any of the participants, but in the age group 18-29 years divers performed significantly better than non-divers (p= 0.01). CERA revealed no significant differences between divers and non-divers in the age group 18-29 years and 30-39 years, whereas divers in the age group 41-50 demonstrated significantly better test results (p=0.045) (difference of the means: 4.18 dB). Conclusion: Dichotic listening and CERA did not reveal a significant reduction of central hearing performance in divers. Persistent on-shore BERA wave latency prolongations that were present in one study could not be confirmed in our study group. This first comprehensive topographic examination of the central hearing system of divers showed no abnormalities

    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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