1,720,961 research outputs found
A novel pneutronic device for the investigation of compression-induced physiological phenomena: Modeling and experimental testing
Full text linkAn automatic pneumatic system designed to investigate the physiological effects induced by limb compressions, able to apply customizable pressure patterns in the physiologic range (0–200 mmHg), is here presented. A mathematical model, simulating the whole pneutronic system and its interaction with the limb is described. The model is validated by means of experimental tests. An on-going study aiming to investigate the role of different factors in the development of post compression hyperemia is presented
A validation study of a new instrument for low cost bite force measurement
Full text linkQuantitative assessment of force in masticatory muscles is not a routine clinical test, probably due to the lack of an “easy-to-use” device. Aim of this study is (1) to present a low cost bite force instrument located in a custom-made housing, designed to guarantee a comfortable and effective bite action, (2) to evaluate its mechanical characteristics, in order to implement it in clinical settings and in experimental setups. Linearity, repeatability and adaptation over time were assessed on a set of four different sensors in bare and housed condition. Application of the housing to the transducer may appreciably alter the transducer's response. Calibration of the housed transducer is thus necessary in order to correctly record real bite force. This solution may represent a low cost and reliable option for biting force measurement and objective assessment of individual force control in the scientific and clinical setting
Design and Simulation of a Novel Pneumotronic System Aimed to the Investigation of Vascular Phenomena Induced by Limb Compression
Full text linkIntermittent Pneumatic Compression (IPC) devices can be used to analyze the mechanisms underlying several vascular phenomena, such as hyperaemia. Commercial devices have limited dynamics and do not allow the delivery of customizable compressive pressure patterns, making the analysis of such phenomena difficult, which may require the application of long stimulations with low amplitude as well as fast compressions with higher pressure level. To overcome these issues, a novel pneumotronic device aimed to the investigation of the physiological effects induced by limb compressions is conceived and presented in this work. The design requirements of the system, capable of delivering customizable compressive patterns in the range 0 mmHg - 200 mmHg, are outlined. The final prototype architecture is described, and a mathematical model of the entire system, also including the interaction between the device and the limb tissues, is proposed. The performance of the device was evaluated in several conditions by means of simulations, whose results were compared to the data collected from experimental trials in order to validate the model. The outcomes of both experimentation and simulation trials proved the effectiveness of the solution proposed. A possible employment of this device for the investigation of the rapid compression-induced hyperaemia is presented. Other potential applications concern the wide range of intermittent-pneumatic compression treatments
Delivery of customizable compressive patterns to human limbs to investigate vascular reactivity
Full text linkObjective: Commercial devices for pneumatic compressive treatment of the limbs generally provide
predefined stereotyped compressive profiles. The possibility to deliver compressive stimuli with a
customizable pressure profile would be useful to differently probe the vascular reactivity to muscle
compression (MC) and improve the understanding of MC-induced hyperemia. Aim of this study was the
realization of a novel pneumatic system capable of generating adjustable and stable compressive
conditions, preceding and following a ‘standard’MC stimulus. Approach: A custom-made pneumatic
system specifically built to this purpose is tested and characterized in 10 subjects. Three different
compressive patterns were delivered to the leg: (1) a constant level: 50mmHg for 50 s; (2) MC: 200mmHg
for 1 s; (3) a complex profile: 20mmHg for 50 s, 200mmHg for 1 s, 50mmHg for 50 s. Main results: The
implemented system allowed to deliver graded compressions to the limb characterized by fast transitions
(0 to 200mmHg in 0.5±0.07 s) and stable plateau levels (50.4±0.5mmHg). Significance: A new, low-cost,
pneumatic prototype has been presented and tested in the present study allowing to deliver
compressive stimuli with pre-and post-compressions of adjustable level.This device has been conceived
for research purposes and may find application in therapeutic compressive treatments
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
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
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