1,720,969 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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 impact of pole use on vertical cost of transport and foot force during uphill treadmill walking before and after a simulated trail running competition
No full textPurpose: Trail running poles are widely used among trail runners but their effects on cost of transport and biomechanics under fatigued conditions remains understudied. This study aimed to evaluate the effects of pole use on the walking vertical cost of transport (CoTvert) and foot force (FF) before and after a simulated trail running competition (STRC). Methods: Sixteen trail runners (V ̇O2: 61.0 ± 8.3 ml/kg/min; ITRA performance index: 634 ± 107 points) performed walking trials with (PW) and without poles (CW) on an incline treadmill (18.6 degrees) before (PRE) and after (POST) a STRC. The course covered 31.2 km with 2086 m of elevation gain and was completed under race-simulated conditions. CoTvert and FF were measured using instrumented insoles, and axial pole force was recorded during PW. Results: The STRC was completed in 4:25:33 ± 0:39:51 (hh:mm:ss) at an average heart rate (HR) of 81.4 ± 3.8% of HRmax. Walking CoTvert showed significant time and condition effects, with higher values without poles at POST (+ 2.50 ± 2.62%, p = 0.0183). Rating of perceived exertion (RPE) was lower with poles at both PRE and POST (p = 0.0022 and p = 0.0187, respectively). FF was significantly lower with poles at PRE (p = 0.0140) and POST (p < 0.0001). Poling force decreased at POST compared to PRE (p = 0.0026). Conclusions: The main findings are that (1) CoTvert increases after STRC; (2) walking CoTvert and FF are lower with pole use and (3) upper limb force decreases at POST. These results support the use of poles in long-lasting events to reduce CoT, redistribute workload and possibly mitigate the fatigue effects
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Independent, additive and interactive effects of acute normobaric hypoxia and cold on submaximal and maximal endurance exercise
Full text linkPurpose: To evaluate the independent and combined effects of hypoxia (FiO2 = 13.5%) and cold (- 20 °C) on physiological and perceptual responses to endurance exercise. Methods: 14 trained male subjects ([Formula: see text]O2max: 64 ± 5 mL/kg/min) randomly performed a discontinuous maximal incremental test to exhaustion on a motorized treadmill under four environmental conditions: Normothermic-Normoxia (N), Normothermic-Hypoxia (H), Cold-Normoxia (C) and Cold-Hypoxia (CH). Performance and physiological and perceptual responses throughout exercise were evaluated. Results: Maximal WorkLoad (WL) and WL at lactate threshold (LT) were reduced in C (- 2.3% and - 3.5%) and H (- 18.0% and - 21.7%) compared to N, with no interactive (p = 0.25 and 0.81) but additive effect in CH (- 21.5% and - 24.6%). Similarly, HRmax and Vemax were reduced in C (- 3.2% and - 14.6%) and H (- 5.0% and - 7%), showing additive effects in CH (- 7.7% and - 16.6%). At LT, additive effect of C (- 2.8%) and H (- 3.8%) on HR reduction in CH (- 5.7%) was maintained, whereas an interactive effect (p = 0.007) of the two stressors combined was noted on Ve (C: - 3.1%, H: + 5.5%, CH: - 10.9%). [La] curve shifted on the left in CH, displaying an interaction effect between the 2 stressors on this parameter. Finally, RPE at LT was exclusively reduced by hypoxia (p < 0.001), whereas TSmax is synergistically reduced by cold and hypoxia (interaction p = 0.047). Conclusion: If compared to single stress exposure, exercise performance and physiological and perceptual variables undergo additive or synergistic effects when cold and hypoxia are combined. These results provide new insight into human physiological responses to extreme environments
Do poles really “save the legs” during uphill pole walking at different intensities?
No full textPurpose: In sky- and trail-running competitions, many athletes use poles. The aims of this study were to investigate whether the use of poles affects the force exerted on the ground at the feet (Ffoot), cardiorespiratory variables and maximal performance during uphill walking. Methods: Fifteen male trail runners completed four testing sessions on different days. On the first two days, they performed two incremental uphill treadmill walking tests to exhaustion with (PWincr) and without poles (Wincr). On the following days, they performed submaximal and maximal tests with (PW80 and PWmax) and without (W80 and Wmax) poles on an outdoor trail course. We measured cardiorespiratory parameters, the rating of perceived exertion, the axial poling force and Ffoot. Results: When walking on the treadmill, we found that poles reduced maximum Ffoot (− 2.8 ± 6.4%, p = 0.03) and average Ffoot (− 2.4 ± 3.3%, p = 0.0089). However, when outdoors, we found pole effect only for average Ffoot (p = 0.0051), which was lower when walking with poles (− 2.6 ± 3.9%, p = 0.0306 during submaximal trial and − 5.21 ± 5.51%, p = 0.0096 during maximal trial). We found no effects of poles on cardiorespiratory parameters across all tested conditions. Performance was faster in PWmax than in Wmax (+ 2.5 ± 3.4%, p = 0.025). Conclusion: The use of poles reduces the foot force both on the treadmill and outdoors at submaximal and maximal intensities. It is, therefore, reasonable to conclude that the use of poles “saves the legs” during uphill without affecting the metabolic cost
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