1,720,960 research outputs found
A Portable Ultrasound Procedure to Enable Remote Management of Tennis Leg Injuries
No full textUltrasound (US) technologies are widely accepted for assessing Tennis Leg injuries. However, their integration into tele-ultrasonography systems faces various challenges, including operator dependency and lack of a viable procedure to acquire clinically effective ultrasound images at home. Here, we introduce a standardized ultrasound procedure to address these challenges, ensuring the remote acquisition of images with accurate and repeatable visualization of the target lesion. The procedure includes the use of a wearable, removable skin tattoo to guarantee a correct and repeatable position of the ultrasound probe by non-expert users and an image processing method to recognize and quantify the lesion area and contrast automatically. The feasibility of this procedure was tested on a volunteer, who conducted self-acquisitions on day 0 and on day 48 after the evaluation made by an expert clinician. Results demonstrate the feasibility of standardizing ultrasound data acquisition with accurate visualizations of the target lesion, evidencing the potential of this procedure for tele-ultrasound platforms. Moreover, for the first time, we introduce two objective measurements based on area and texture analysis to detect changes in the tennis leg injuries
Optical and Electromagnetic Tracking Systems for Biomedical Applications: A Critical Review on Potentialities and Limitations
No full textOptical and electromagnetic tracking systems represent the two main technologies integrated into commercially-available surgical navigators for computer-assisted image-guided surgery so far. Optical Tracking Systems (OTSs) work within the optical spectrum to track the position and orientation, i.e., pose of target surgical instruments. OTSs are characterized by high accuracy and robustness to environmental conditions. The main limitation of OTSs is the need of a direct line-of-sight between the optical markers and the camera sensor, rigidly fixed into the operating theatre. Electromagnetic Tracking Systems (EMTSs) use electromagnetic field generator to detect the pose of electromagnetic sensors. EMTSs do not require such a direct line-of-sight, however the presence of metal or ferromagnetic sources in the operating workspace can significantly affect the measurement accuracy. The aim of the proposed review is to provide a complete and detailed overview of optical and electromagnetic tracking systems, including working principles, source of error and validation protocols. Moreover, commercial and research-oriented solutions, as well as clinical applications, are described for both technologies. Finally, a critical comparative analysis of the state of the art which highlights the potentialities and the limitations of each tracking system for a medical use is provided
A novel approach for remote ultrasonography of knee osteoarthritis
No full textIn this study, we propose innovative technologies and a novel standardized procedure, enabling at-home, periodic and reliable ultrasound monitoring of knee osteoartrithis. Anatomical and ultrasound data were collected on a population of 27 volunteers with different anthropometric features, leading to the development of two technological solutions: i) three probe positioning systems (wearable brace, adhesive film, temporary tattoo), provided with predefined openings to ensure accurate and repeatable placement of an ultrasound probe; ii) an image selection algorithm for automatic identification of the correct ultrasound images acquired by non-expert users. The effectiveness and usability of these solutions were tested on 20 volunteers and 20 caregivers, with no prior experience in ultrasound imaging. In the first step, an expert radiologist acquired reference ultrasound images. In the second step, all volunteers exploited the positioning systems to place the probe and acquire informative images (automatically extracted by the algorithm from a video). The average usability percentage score was highest for the wearable brace (98.7%), followed by the tattoo (94.8%), and film (89.6%). Overall, the three positioning systems proved to be effective in guiding ultrasound acquisitions for inexperienced subjects. The highest average rate of informative images successffully acquired among all volunteers was achieved by using the brace (70%), while the highest average score among the caregivers was obtained using the tattoo (76%). These findings highlight the possibility to perform reliable remote ultrasound acquisitions for non-expert users and opens the way to novel tele-ultrasound procedures, enabling a precise, asynchronous, and repeatable monitoring of knee osteoarthritis
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
- …
