1,720,959 research outputs found
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
The development of a new comprehensive management model for Apophysitis Syndromes in adolescents, based on the assessment and management of passive muscular tension
Get PDFIntroduction: To date there appears to be no consensus to the accepted management of Apophysitis syndromes (AS) and no coherent research towards one. Despite these conditions being amongst the most common injuries to affect adolescents, and in particular young athletes, most recommended approaches are based on opinions and experience only. This thesis presents a new comprehensive approach to the management of AS in the lower limb, based on an assessment of local passive muscular tension as demonstrated by reduced flexibility.
Method: A new theoretical model of passive and active tension underlying AS is proposed and used to demonstrate the new approach. Four main studies are presented. The first study examined a novel treatment of the most common AS in adolescents – Osgood-Schlatter’s disease (OSD). The same approach was applied to a different AS – Sever’s disease, in the second study. The third examined the role of growth and flexibility during adolescence in a longitudinal study to ascertain the influence of passive tension in the development of AS, and finally an experimental stretching intervention study addressing reduced flexibility in young footballers, was performed as a preventative strategy for AS, and compared to current incidence rates from 3 football academies. Together they present a coherent strategy for the treatment, aetiology and ultimately prevention of AS.
Results: Findings from the OSD study found that reducing passive tension in the quadriceps muscle enabled the recovery of patients in a median of 17 days (6- 40). Similar results of 13 days (5-42) occurred in the second study on Sever’s disease treatment. Monitoring growth and flexibility during adolescence in academy football players found that flexibility significantly reduced in academy footballers prior to developing AS, and there was a strong negative correlation between growth rate and muscle flexibility (-0.96 and -0.97) for the quadriceps and calf muscles respectively. Introducing a stretching programme as an intervention to those whose flexibility exceeded set thresholds, showed none of these players went on to develop an AS. Incidence of AS was shown to have declined in the intervention club by 69% compared with control clubs 7% and 15%.
Conclusion: Increased passive tension during adolescent growth appears to be associated with the development of AS. Addressing this during treatment improves the outcomes for patients and can be part of a preventative strategy for potential at- risk players. Everyone involved in encouraging youth sports should be aware of the problem of AS and recognize the need for a proactive flexibility approach during the peak adolescent growth spurt. This study presents the arguments and creates the opportunity to promote widespread changes for the good of adolescent well-being and health
Human physiological and biomechanical responses to vibration exercise
Get PDFThe role of vibration in exercise is controversial, with much debate about its potential benefits. The aim of the research reported in this PhD thesis was to inform evidence based practice by investigating the underlying responses of the human body during exercise with vibration. Human neuromuscular and cardiovascular systems were investigated using 3D motion analysis, near infra-red spectroscopy (NIRS), laser Doppler blood flow analysis and electromyography (EMG).
Analysis of a prototype vibrating stationary cycle identified significant increases in muscle activation. However, the validity of the results was limited by a confounding issue of increasing resistance with increasing cadence due to the cycle’s vibration mechanism. Consistency of exercise performance on vibration platforms was measured by 3D analysis; vibration did not affect the kinematic parameters of exercises such as heel raises or press ups, even though significant physiological changes occurred. NIRS indicated a significant reduction in the depletion of oxygenated haemoglobin, total haemoglobin and the normalised tissue haemoglobin index of the lateral gastrocnemius in heel raise exercises. During quiet standing laser Doppler measurements of the dorsalis pedis artery indicated that the NIRS results were not a consequence of vasospastic responses or increased resistance to blood flow in response to vibration. Whilst heart rate and blood pressure remained constant, blood flow velocity significantly increased, suggesting the peripheral changes occurred independently of central cardiovascular function.
Heel raise exercises with whole body vibration showed significant increases in muscle activation of the soleus, but not the gastrocnemius, indicating varied muscular responses to vibration. The influence of blood flow and tissue oxygenation on EMG parameters was demonstrated via the protection of muscle conduction velocity during static squats, despite a downward shift in median frequency of the EMG power spectra.
Analysis of upper body muscles during press ups yielded significant increases in muscle activation, equivalent to increasing the load of the bench press by 10% of the one repetition maximum. The results indicate that vibration influenced the dynamic muscles more than stabiliser muscles; reinforcing the lower body studies showing that vibration has a varied influence on muscle function. The aforementioned results demonstrate the ability of vibration to augment the effects of exercise on the muscular and vascular physiological systems of the human body
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
THE IDENTIFICATION OF IMPULSES IN 3-D RECONSTRUCTED DATA USING RECURSIVE FILTERS ON THE ORIGINALLY DIGITIZED 2-D IMAGE DATA
Get PDFINTRODUCTION: Reconstructed three-dimensional (3-D) data is usually processed using either a low-pass Butterworth filter or quintic spline, though neither gives an implicit indication that the processed data is more accurate than the original data. This study investigated the effect of processing the original twodimensional (2-D) data before reconstruction, a technique commonly applied in the communications industry (e.g., the removal of noise prior to amplification).
Reconstruction of the 3-D data can be considered successful when the condition of coplanarity is met (i.e., the lines from each centre of projection pass through their respective image points and intersect at the object point). The 3-D data is considered to be more accurate if the lines converge after processing (i.e. the residual error of the reconstructed points was reduced) and less accurate if the lines diverge.
The independent application of a recursive filter in both forward and backward directions to the 2-D data enables the detection of a discontinuity. Each original 2- D data set can then be considered as two different data sets whose paths intersect at the discontinuity caused by an impulse. The timing of the impulse can be calculated from the extrapolated curves even if it was not explicitly captured on film.
METHOD: Two cameras were located so that their optical axes were approximately orthogonal to each other and a 3-D volume was calibrated to generate the linear transformation parameters. A bouncing ball was then filmed within the calibrated volume, digitized and then passed through a Kalman filter in both the forward and backward directions to determine the timing of the impulse, (i.e., when the ball hit the ground).
RESULTS: Two cameras provide four image co-ordinates and thus four equations with three unknowns so the 3-D object space co-ordinates were calculated using least squares estimation. To ensure only random noise was removed, the processed 2-D signal must have the same total energy as the original 2-D signal, even if the energy density spectrum has altered and the filter was deemed to be effective if the residual error of the reconstruction was reduced. Using this method, it was possible to identify when the impulse forces occurred, for both image sets, independently.
CONCLUSIONS: This technique breaks a signal down into a series of discontinuous signals, each discontinuity indicating the application of an impulse to the original measured data. With proper camera placement any impulse can be observed independently in both the 2-D images so the impulses can also be used to synchronize previously unsynchronized data
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