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Riabilitazione robotica della postura in Pediatria; progettazione, sviluppo, implementazione del sistema di controllo e sensorizzazione di un robot riabilitativo e sua utilizzazione nella routine clinica
No full textThe ability to maintain postural control is a complex task and, although it is natural for healthy subjects, it is often disrupted in stroke patients. The control of posture, in fact, results from the integration of several sensory inputs, both from the body and the external environment; these inputs are real-time processed to implement a dynamic equilibrium configuration for the entire musculoskeletal system.
Postural rehabilitation has grown remarkably in the neuro-rehabilitation field and has met new challenges in the so-called cortical plasticity¬, which is also the rationale for rehabilitation robotics. This principle, in fact, states the ability of the CNS to reorganize itself, even after a cerebrovascular accident. This reason led to the introduction, during the last years, of a huge number of robotic platforms to improve the postural rehabilitation process, both in the fields of Research and clinical routine.
The lack, in the literature, of a motorized, 2 DOFs platform, able to interact with the subjects standing upon it, led to the design of a device with these requirements, intended for use by the pediatric patients of the MARlab (Movement Analysis and Robotics laboratory, Ospedale Pediatrico “Bambino Gesù”, Palidoro, RM). After the dimensioning of the selected components, the platform has been designed in a CAD environment. The final layout is a Cartesian robot with a 15x15 cm2 workspace and a low profile (170 mm), and it is ideal to be installed, in the future, below the floor.
Two linear induction motors are used to power the two motion axis and, in order to make the platform compliant with the patient, each motor slider was sensorized with a 1DOF load cell. A study was then conducted to evaluate the influence of the inertial forces over the load cell output.
The goal of this project was to design and realize a robot prototype, called SlideBiT2D, with an open, evolvable architecture. For this reason we chose to install the network of sensors and actuators over a CAN fieldbus; we also selected, as the network master node, a PCI card CANopen-compliant, which could be programmed in LabVIEW environment. As regards the software, it has been designed on a three-level structure, two of which has already been developed. In this way it is not mandatory to have a good knowledge of the CANopen protocol in order to develop the user interface.
To make the platform a real haptic interface, ie able to respond to the external forces imposed by the patient, we used, for both motors, the speed control mode; in addition, a superior control loop was imposed to simulate a 2DOFs spring, placed in parallel with a damper of coefficient C. The control thus produced was tested first with a test bench, along a single dimension, and was then successfully implemented in 2D, over the platform.
Since the platform is a medical device, some special attentions were used throughout the design activities. As regards the requirements for electrical safety, the development of the electrical panel was demanded to a certified company (MPD Ltd – Induno Olona, VA). The use of the platform before its installation under the floor will be conducted in combination with the use of the overhead crane installed in the MARlab of Santa Marinella. Finally, the platform commissioning/start-up will require further calibration phase for motors and load cells, in order to assure quality measurements and safe interaction of the robot with the patient.Il mantenimento della postura è un compito complesso, pur nella sua apparente naturalezza, ed è spesso compromesso in pazienti con patologie a carico del Sistema Nervoso Centrale (SNC). Questo compito è, infatti, frutto dell’integrazione di numerosi input sensoriali, propriocettivi ed esterocettivi, da parte del SNC; tali input vengono elaborati per attuare, in ogni istante, durante tutte le attività quotidiane, una configurazione di equilibrio per l’intero apparato muscoloscheletrico.
La riabilitazione del mantenimento della postura ha acquistato importanza sempre crescente nel campo della neuro-riabilitazione ed ha conosciuto nuovi stimoli nel razionale della terapia mediata da robot, la quale si fonda sul concetto della plasticità corticale, ossia sulla capacità del SNC di riorganizzarsi anche a seguito di accidenti cerebrovascolari. Per questo motivo, gli ultimi decenni hanno visto l’introduzione di numerose piattaforme robotiche sia in Ricerca che in Clinica, allo scopo di migliorare il processo di recupero dell’equilibrio e la sua oggettivazione.
L’assenza, in letteratura, di una piattaforma motorizzata a 2 gdl (gradi di libertà), e in grado di interagire con i soggetti posti al di sopra di essa, hanno portato alla progettazione di un dispositivo con queste caratteristiche, destinato all’utilizzo da parte dei pazienti pediatrici del MARlab (Movement Analysis and Robotics laboratory) dell’OPBG (Ospedale Pediatrico “Bambino Gesù”) di Palidoro (RM). Dopo l’individuazione delle specifiche di progetto, la scelta e il dimensionamento dei componenti, la piattaforma è stata disegnata in ambiente CAD, risultando un robot cartesiano con un workspace di 15x15 cm2 ed un basso profilo (170 mm), ideale per essere in futuro installata al di sotto del pavimento.
Il cuore del dispositivo è costituito dai due motori lineari a induzione elettromagnetica LinMot, che consentono di attivare ciascuno una direzione del moto. Al fine di rendere la piattaforma interattiva, è stato necessario sensorizzare ciascun motore con una cella di carico, così da rilevare la volontà esterna di muovere il robot. Inoltre, trattandosi di un dispositivo destinato a pazienti pediatrici, aventi cioè massa corporea confrontabile con quella della piattaforma, è stato condotto uno studio per valutare la possibilità di compensare in accelerazione le uscite delle celle di carico, depurandole dalla forza di inerzia associata proprio al moto della piattaforma.
La filosofia di approccio alla costruzione di questo prototipo, denominato SlideBiT2D, è quella di un sistema aperto ed evolvibile, sia dal punto di vista dell’hardware che del software, pronto ad accogliere nuove necessità espresse da parte del personale medico. Per questo, si è scelto di installare la rete di sensori e attuatori su bus di campo CAN, scegliendo come master della rete un nodo CANopen-compliant, programmabile però in ambiente LabVIEW. Il software è stato concepito come articolato su tre livelli e ne sono stati sviluppati i due più bassi, in modo da svincolare la creazione di una interfaccia utente da qualsiasi conoscenza del CANopen, protocollo molto efficiente ma anche complesso da apprendere.
Per rendere la piattaforma una vera e propria interfaccia aptica, in grado cioè di rispondere alle sollecitazioni imposte dall’esterno, i motori sono stati controllati in velocità e, in più, è stato sviluppato un controllore di livello superiore per simulare una molla a 2 gdl, di rigidezza variabile K, posta in parallelo ad uno smorzatore con coefficiente C. Il controllo così realizzato è stato testato dapprima con un banco di prova, lungo una sola dimensione, ed è stato poi implementato con successo in 2D sulla piattaforma.
Avere a che fare con un prototipo di un dispositivo medico ha richiesto alcune attenzioni particolari durante tutta la attività di progettazione. Anzitutto, per ciò che riguarda la sicurezza elettrica, il quadro elettrico è stato sviluppato da una ditta certificata (MPD srl – Induno Olona, VA). L’utilizzo stesso della piattaforma, in attesa che essa sia interrata, sarà auspicabilmente condotto in combinazione con l’utilizzo di un carroponte in dotazione al MARlab dell’OPBG di Santa Marinella. Infine, come si conviene ad ogni dispositivo di misura, la messa in opera del robot richiederà una ulteriore fase di taratura dei motori e delle catene di misura presenti, al fine di garantire la qualità delle misure e la sicurezza nella interazione per il paziente.. Infine, come si conviene a un qualsiasi dispositivo di misura, la messa in opera del robot richiederà una ulteriore fase di taratura dei motori e delle catene di misura presenti, al fine di garantire la qualità delle misure e la sicurezza nella interazione per il paziente
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
Choosing a similarity index to quantify gait data variability
Full text linkRepeatability and reproducibility of joint kinematics can be assessed through Similarity Indices (SI) quantifying their pattern variability. These include: Coefficient of Multiple Correlation (CMC) [1]; Mean Absolute Variability (MAV) [2]; and Linear Fit Method (LFM) [3], which accounts for scaling (a1), offset (a0) and truthfulness of the linear model between the curves (R2). Among gait cycles, the intra-subject variability for a given joint is due to physiological fluctuations of the range of motion (ROM) and time shift. SIs might be differently affected for each joint, due to their different ROMs, and by marker positioning, leading to offsets among gait curves. This paper aims to investigate the effects that each of these sources of curve variability has on the SIs, in order to provide indications on which is the most suitable for the assessment of gait similarity
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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