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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
Analisi Biomeccanica del Push-up Eseguito in Sospensione
No full textL'allenamento in sospensione, che necessita solo dell’utilizzo di un piccolo attrezzo e del proprio peso corporeo, ha recentemente acquisito grande popolarità. Sebbene la letteratura abbia mostrato che l’esecuzione di esercizi mediante il dispositivo per l’allenamento in sospensione aumenti l’attivazione neuromuscolare rispetto allo stesso esercizio eseguito tradizionalmente, la difficoltà principale sta nel quantificare il carico di lavoro. Infatti, nonostante alcuni ricercatori abbiano affermato che il carico cambi al variare dell’angolo di inclinazione del soggetto o del dispositivo, misurare gli angoli durante una seduta di allenamento risulta complicato, tanto che nessuno studio ha valutato la variazione del carico di lavoro al variare della lunghezza del dispositivo. L’ipotesi dello studio è che il carico di lavoro possa variare al variar della lunghezza del dispositivo per l’allenamento in sospensione. Pertanto lo scopo di questo studio è verificare l'andamento del carico di lavoro al variare della lunghezza delle cinghie durante l'esercizio del push-up eseguito mediante dispositivo per l'allenamento in sospensione. Sedici soggetti volontari (8 femmine e 8 maschi; età 26,8±4,9 anni; massa corporea 62,6±12,2 kg; statura 168,6±9,9 cm; BMI 21,8±2,6 kg/m2) hanno partecipato allo studio. Il protocollo prevedeva l’esecuzione dell’esercizio del push-up mediante dispositivo per l’allenamento in sospensione in 2 diverse posizioni delle braccia in 7 diverse lunghezze del dispositivo, per un totale di 14 push-up statici della durata di 5 secondi ciascuno. Durante gli esercizi, una piattaforma di forza e un trasduttore di forza sono stati utilizzati per registrare rispettivamente il carico al suolo e la forza di trazione applicata al dispositivo. Tutte le prove sono state registrate mediante una videocamera e analizzate successivamente mediante un software di video analisi per valutare l’angolo di inclinazione del soggetto rispetto al suolo. I risultati hanno mostrato come il carico di lavoro si modifichi al variare sia dell’angolo di inclinazione del soggetto, sia della lunghezza del dispositivo utilizzato. In particolare, all’aumentare della lunghezza del dispositivo, aumenta il carico di trazione sul dispositivo stesso mentre diminuisce la forza al suolo. In conclusione possiamo affermare che, durante l’esercizio del push-up, la distribuzione del carico tra arti superiori e inferiori varia sia al variare dell’angolo di inclinazione del soggetto, sia al variare della lunghezza delle cinghie di regolazione. Questi risultati potrebbero aiutare a personalizzare gli allenamenti e creare una corretta progressione del carico di lavoro, iniziando da lunghezze ridotte per poi aumentarle dopo una fase di familiarizzazione
Relationship between Anthropometrics and Dynamic Balance Performances
No full textDynamic balance performances are highly affected by the base of support, the
center of gravity and its projection within the base of support. Although anthropometric
characteristics could be expected to affect dynamic balance performances1,
there is a need to substantiate this relationship. Therefore, the aim of this study was
to evaluate the relationship between anthropometric measurements and dynamic balance
performances. After signing an informed consent, 26 (female, n=14; male, n=12)
college students (25.7±3.4years) were involved in the study. Body mass, height, sitting
height, and foot size were measured, whereas lower limbs length was calculated
as the difference between standing and sitting height. Dynamic balance performance
was assessed on a wobble board (Balance Board WSP, GSJ Service, Rome, Italy;
diameter=40cm) as the time spent in the target zone (diameter=6.3cm) displayed on
a screen. Participants were asked to stand barefoot on the wobble board with a comfortable
double leg stance, keeping their hands on the hip and looking at the screen
(displaying performance in real time). After a 3-minute familiarization, three 30-second
trials were performed with one minute sitting recovery in between. A correlation
analysis (p<0.05) was applied to anthropometrics and balance performances (the best
score out of three trials). Time in the target zone (12.7±5.9s) was significantly related
to weight (63.8±12.6kg; r=-0.46, p=0.02) and foot size (25.3±1.5cm; r=-0.42, p=0.03),
whereas no significant correlation emerged with respect to height (167.0±10.3cm) and
lower limbs length (79.6±6.7cm). Therefore, individual anthropometric characteristics
should be considered when evaluating dynamic balance performances. Further studies
are needed to investigate the relationship between anthropometric characteristics
and the length and area of sways, and lateral movements of the center of mass
LOAD DISTRIBUTION DURING SUSPENSION TRAINING EXERCISE
No full textINTRODUCTION: Suspension training (ST) uses body weight in multi-directional movements as a form of exercise and due to its feasibility
promotes a large variety of workouts within a low space occupancy. However, only few studies (1,2) investigated the load distribution
during ST, especially during pulling exercises. Therefore, the aims of this study were to evaluate body inclination and ground reaction
force and to predict equations to estimate the training load distribution during ST static back-row at different length of the straps.
METHODS: Thirty volunteers (men=16, women=14; age=23.3±1.7years; body weight=63.9±13.3kg; height=167.9±9.2cm; Body Mass Index
[BMI]=22.5±3.4kg·m-2) performed 14 static ST back-row (holding for 5s) at seven different lengths of ST device (148cm, 158cm, 168cm,
178cm, 188cm, 198cm, 208cm) ranging from the simplest to the most challenging, in 2 different elbow (flexed, extended) positions. A ST
device (AINS ST FIPE, Italy) was anchored at 2.65m above a force platform. Subjects stood barefoot on the force plate, with their feet
shoulder width apart positioned under the anchored point and visual reflective markers applied to subjects’ left lateral malleolus and at
the acromion process. The force platform was used to evaluate the ground reaction force, whereas a video camera was used to record
all the trials. The recorded videos were then analyzed to calculate the body inclination angle with respect to the horizontal plane. Ground
reaction force and body inclination were used to predict training load equations trough multi-level regression models (P<0.05).
RESULTS: Two multi-level regression models were created. In the first one, ground reaction force was used as dependent variable,
whereas body inclination angle, body weight, height, BMI and elbow position were used as independent variables. Significant effects
were found for all variables included in the model, with an Intraclass Correlation Coefficient (ICC) of 0.31. Analyzing the model, the follow-ing equation to estimate the ground reaction force was extrapolated: Load=-132.9134+0.3724671·Angle-1.299028·Body
weight+0.9844512·Height+3.675008·BMI-2.073684·Elbow.
In the second model (ICC of 0.37), the body inclination angle was replaced by the ST device’s length. By analyzing this model, the following equation to estimate the ground reaction force knowing the length of the straps was extrapolated: Load=-69.80267-
0.2199257·Length-1.281452·Body weight+0.8883487·Height+3.624841·BMI+5.188559·Elbow.
CONCLUSION: The proposed models could provide different methods to quantify the training load distribution, even if the use of the
straps’ length could result easier and faster than body inclination angle, helping practitioners and instructors to personalize the workout
to reach specific purposes and provide load progression.
References
1) Giancotti et. al., J Strength Cond Res, 2018.
2) Gulmez, J Strength Cond Res, 2017.
Key-words: body weight; instability; back-row; resistance training; functional training; biomechanic
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
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