1,721,518 research outputs found
Mean movements and strategy in sport climbing : determinant variables and performance factors
Full text linkIntroduction
Climbing, in all its disciplines, is a emergent sport with a increasing number of athletes involved in competition. The major discipline is the leading, characterized by strength and endurance movements on overhanging artificial structures. Score depends on the height reached by athletes. The ascent needs physical, technical and interpretation ability. Increasing performances and specializations need well specified training programs but, at the moment, this kind of sports lacks in scientific studies about kinematics variables and movement strategy. The aim of this study is to collect preliminary kinematics data to identify mean movements and strategy in sport climbing and to verify if it’s possible to find determinant variables and performance factors.
Methods
Data of kinematics variables were extracted from a video analysis of 8 female athletes who participated at 2007 Lombardia Regional Cup match. The athletes (20±4 years old, 49±5 kg, 162±4 cm) involved in this study are all well experienced climbers with at least 2 years of competition participation. Following variables were collected: total time, number of holds, speed (mean time for hold), number and time of rests, number and time of clipping, number of hands and feet movements, contraction type (concentric or isometric) time per holds, support type (on holds or on structure) time, technical movements (frontal, lateral, etc) used. All these variables were extrapolated by the digital video analysis frame per frame with “final cut pro” software. Data were imported in excel file format
witch ensures simple charts vision and different manipulations to identify differences among athletes on the same route or between different route climbed by one athletes. For each athlete, data were analyzed on the entire height climbed. For interindividual analysis, data were compared normalizing the minimum height reached among all climbers. These information were related with the difficulties of any segments of the routes.
Results
The 2 matches analyzed were characterized by overhanging structures where a lot of endurance movements interrupted by two bouldery sections with strength and technical needing. In both competitions the best results were reached by the fastest athletes with less per cent time spent in concentric phases and clipping. We see that the best athletes are more time in double feet support than the worst ones, and use less movements to reach the same height. Different climbing styles (dominant movements and rhythms) demonstrate to be efficacy at the same way. Comparison between the 2 routes climbed by the same athletes shows that, when it is possible, they choice the climbing style according to their technical and conditioning characteristics.
Discussion
It seems that technical and conditional characteristics are the major variables and their influence is dominant on kinematics data. Total climbing time and technical movements choice are not statistically correlated with results because they depend by individual muscular characteristics, specific technique awareness and routes interpretation. The variables related with results are: clipping time, concentric phase time, mean holding time, movements number and support type time. Finally this analysis method can help to have a better view of athletes profile and to find out weakness points in respect of the racing routes. Interpretation of kinematics data related with physiological aspects is the way to discover determinant results factors and to improve training technique
La Pirateria nel Corno d'Africa, Prefazione al volume di M. Sacchi
No full textAllorché si prendono in esame vaste regioni come il Corno d’Africa, il Mar Rosso e l’Oceano Indiano le insidie sono numerose; innanzitutto gli ‘sguardi’, e cioè le prospettive e le scelte metodologiche: il Mar Rosso e l’Oceano Indiano occidentale “visti” dall’Europa, dall’Asia, dall’Arabia e dall’Africa modificano radicalmente le tematiche affrontate e le relative conclusioni. Così come le scelte, obbligate o meno, di privilegiare il mare, le prospettive marittime, o la terra, le terre, e le relative problematiche terrestri possono alterare considerevolmente i percorsi di ricerca
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
Microbiological deterioration of Gambara's frescoes exposed to open air in Brescia, Italy
No full textMicrobiological studies were carried out on samples taken from L. Gambara's deteriorated frescos, painted on outside walls of two buildings in Brescia, Italy, in the 16th century. The results showed that aerobic heterotrophic bacteria, fungi, ammonifiers and sulphur-oxidizing bacteria were present in all samples and in most cases were well above the levels considered damaging; only fungi and sulphur-oxidizing bacteria counts underwent variations relating to climatic conditions. Moreover, some fungi are able to grow in the presence of malachite and haematite, used as pigments for frescos, but not limonite. The same fungi change the green colour of malachite into blue
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
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
Pre-Quaternary orogen-parallel extension in the Southern Apennine belt, Italy
No full textThe Southern Apennine fold and thrust belt differs from other parts of the peri-Tyrrhenian orogen. In most of the peri-Tyrrhenian belt, hinterland extension is oriented at a high-angle to the orogen axis and appears to be related to rifting and formation of oceanic crust within the Tyrrhenian basin. The Southern Apennines share the late-stage development of normal faults related to the opening of the Tyrrhenian Sea, but also experienced an episode of extension parallel to the strike of the tectonic belt. The orogen-parallel extension was apparently formed in response to the increase in length of the deformed belt during arcuation. Arcuation ostensibly was related to asymmetrical rifting in the hinterland, which was greater in the Southern Tyrrhenian Sea than in areas to the north, and proportionately greater shortening in the frontal parts of the southern belt as compared to regions in the north. During arcuation, extension was spatially concentrated within structural domains and was accomplished by displacement on low-angle detachment faults cutting through a previously imbricated thrust stack. During the Miocene-Pliocene, NNW-SSE extension in the interior of the Southern Apennine belt formed coevally with ENE-WSW shortening in the foreland. Longitudinal extension ceased in the Pleistocene, when younger high-angle normal faults formed in response to the easterly migration of Tyrrhenian Sea rifting and NE-SW extension associated with lithospheric stretching
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