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An investigation into the prevalence and risk factors of occupational low back pain amongst commercial pilots registered with the South African Civil Aviation Authority
Get PDFSubmitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2014.Background
Occupational low back pain (LBP) has been described as a significant burden to society. Although there is uncertainty and conflicting studies on the exact causes and combination of causes of LBP, it has been found that occupations which require prolonged sitting periods and have exposure to physical factors such as whole body vibration (WBV) and / or awkward posture, results in increased likelihood for LBP. Pilots are not sheltered from the development of LBP, with the lifetime prevalence of LBP varying from 31.5% to a significant 82%. Additionally, point prevalence varies significantly between 5.1% and 68%, which illustrates that individual pilot and / or occupational factors may contribute to specific pilot subgroups.
This could apply to commercial pilots, who use seats that were found to be ineffective in terms of their depth and inclination, therefore limiting the height and impact of the lumbar support. There is a paucity of studies performed on LBP relating to commercial pilots, specifically, on their unique occupational setting. Research is therefore warranted to illustrate the possible risk factors to which they are exposed to, as impeded performance may lead to catastrophic consequences if a pilot’s ability to complete actions critical to flight becomes hindered.
Aim
To determine the prevalence of low back pain (LBP) in commercial pilots and identify possible risk factors that pilots are exposed to.
Study designs
The study transpired as a cross sectional questionnaire survey.
Participants
Study comprised of 100 commercial pilots registered with the South African Civil Aviation Authority (SACAA) and affiliated with the various participating companies utilizing O.R. Tambo International Airport.
Methodology
All commercial pilots registered with the SACAA and who make use of the O.R.Tambo International Airport (operate through or from) and affiliated with the participating companies during the research study, was approached for participation. Pilots were required to sign and agree to the letter of information and informed consent, as well as the confidentiality agreement. Questionnaires were distributed and all documents were collected, following completion thereof. Pilots were not allocated to more than one group during the data collection (recording) phase of the study. Subgroup analysis was however not excluded in the analysis. IBM SPSS version 21 was used for analysis. A p value <0.05 was considered as statistically significant. Demographics of the pilots were described in the same manner as in the case of categorical variables, and using summary statistics such as mean, standard deviation and range for quantitative variables. Prevalence and characteristics of the low back pain is described using relative frequency and percentages, with 95% confidence intervals.
Associations between risk factors and low back pain was identified with log linear regression analysis and tested using Pearson’s chi square test in the case of categorical variables and t-tests in the case of continuous variables.
Results
The lifetime prevalence of LBP amongst commercial pilots was 80.8%, with the annual prevalence reaching 68.7%. Majority of commercial pilots were white, married males, with nearly the entire population having reached similar educational levels. Considering the male predominance of this population, gender was significantly associated with LBP. Although the female population was much smaller than the male population, it was also found that females were six times more at risk of developing LBP; however the risk was not statistically significant. Awkward posture such as twisting and being stressed at work were found to be significantly related to LBP. Having a history as an ex-smoker or non-smoker was found to be a risk for LBP development. BMI was also significantly related to LBP; however, an inverse relationship is indicated. Having a subjective rating of good health versus excellent health was also an indicator of risk for LBP.
Conclusion:
Commercial pilots have a significant risk for LBP development. It was found that subjective ratings of own health was a good indicator of LBP whereby good health versus excellent health, was a significant risk factor. Although greater portions of the populace are white males, normally less at risk, a significant lifetime and annual prevalence of LBP was found. Furthermore, the small female population had potentially considerable contribution to the prevalence of LBP through their significant odds ratio. Being a current smoker carried less risk in comparison to a history of an ex-smoker or non-smoker, which further complicates the so often debated contribution of this proposed risk factor. Interesting results were found through the inverse proportional relationship that exists between BMI and LBP, whereby every unit increase in BMI results in a relative decreased risk for LBP development. Majority of the proposed risk factors of LBP was not found to be significant, except stress and twisting, which were found to be common risk factors amongst commercial pilots.
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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