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Gradient limits and safety factor of Alpine ibex locomotion
No full textDam walls are like open laboratories useful to study the gradient limits of locomotion. Two dam walls, where Alpine ibex use to climb searching for the salty exuded, were filmed at 0.2 fps. The straight slope of the walls ranged from 123% to almost vertical. In total 54 animals were filmed and their body mass estimated as medium size, small size and kids. No large males were observed moving on the walls. The overall weighted average incline of their paths was 37% uphill and 46% downhill. They used to climb on zigzag routes and run down on more linear tracks. The gaits employed by the animals were walk and gallop. The steepest paths travelled by kids were 155% up and 157% down, the maximum height was 49 m, while their maximum estimated speeds were 2.6 ms-1 uphill and -4.2 ms-1 downhill. Medium: +143% and -157%; 49 m; +1.1 and -4.1 ms-1. Large: +102% and -123%; 32 m; +0.7 and –1.0 ms-1. The climbing performance of Alpine ibex, in term of speed and inclination, appeared to be negatively influenced by body mass, while the friction coefficient between their hooves and concrete was high, like rubber on solid surfaces.
Protection against toppling depends on the slope and the ratio between the basal width and bCOM height. We propose a safety factor index (Fst), similar to that used in geology, defined as the ratio between the major distance from a downstream to an upstream leg and the centre of mass height, all divided by the tangent of the slope. An index value of “1” is the discriminant between unsafe and relative safe positions. Animals with shorter legs and lower bCOM, like females and kids, can negotiate steeper paths with a higher safety factor
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
An analysis of world records in three types of locomotion
No full textThe record history of running, swimming and ice-skating, over various distances, was analyzed. A mean period of about 66 years for the 18 male events and of about 50 years for the 14 female events was studied. Over a given distance the velocity (v) was related to the dates of the records minus 1900 (T) according to polynomial functions like: Mathematical expression In 21 out of the 32 events equations of first or second degree fitted the experimental data. The mean correlation coefficient was 0.979±0.019 (± S.D.). The ratio between predicted (v1p) and actual value (v1) of the last records was 0.999±0.010. For T corresponding to v1 (T1), the rate of record growth was slowing down in 5 events. Hence up to June 1981 a tendency towards an asymptotic v was not yet a general phenomenon. At T1 the range of the relative rate of increase of v (dvp/dT·(v1p) was 0.9·10-3 per year (800 m - female running) and 12.4·10-3 per year (800 m - female swimming). dv/dT·(v1p) in swimming and skating was similar in both sexes but 4 times faster than in male running. Less marked differences were found for female running. A lowering of the cost of transport was probably the main reason of the fast growth of swimming and skating records. The numerical constants calculated from linear regression of v versus the time of the races over different distances did not seem to have a clear physiological meaning, as reported in the previous literature. © 1982 Springer-Verlag
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
Comparing postoperative quality of life in children after microdebrider intracapsular tonsillotomy and tonsillectomy
No full textObjective: To evaluate postoperative quality of life in patients undergoing microdebrider intracapsular tonsillotomy and adenoidectomy (PITA) in comparison with traditional adenotonsillectomy (AT) and to assess PITA's efficacy in solving upper-airway obstructive symptoms. Methods: 29 children with adenotonsillar hyperplasia referred for AT were included. Patients were divided into two groups: Group 1 (underwent PITA) included 14 children (age 5.1. ±. 1.8 years) affected by night-time airway obstruction without a relevant history of recurrent tonsillitis; Group 2 (underwent AT) included 15 children (age 5.2. ±. 1.7 years) with a history of upper-airway obstruction during sleep and recurrent acute tonsillitis. Outcomes measures included the number of administered pain medications, time before returning to a full diet, Obstructive Sleep Apnea survey (OSA-18), parent's postoperative pain measure questionnaire (PPPM) and Wong-Baker Faces Pain Rating Scale (WBFPRS). Results: Postoperative pain was significantly lower in the PITA group, as demonstrated by PPPM and WBFPRS scores and by a lower number of pain medications used. PITA group also resumed a regular diet earlier (. P<. 0.001). OSA-18 scores proved that both PITA and AT were equally effective in curing upper-airway obstructive symptoms. Conclusion: PITA reduces post-tonsil ablation morbidity and can be a valid alternative to AT for treating upper-airway obstruction due to adenotonsillar hyperplasia
Valutazione della qualità di vita nei pazienti sottoposti a tonsillotomia con microdebrider
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