Les réponses des membres inférieurs à des translations médio-latérales imprévues pendant le mouvement de pédalage

Les perturbations vers la gauche ou vers la droite sont des occurrences quasi-quotidiennes pour un bon nombre de gens. Se faire bousculer en marchant dans la foule ou subir les effets inertiels d'un véhicule de transport en commun tournant ou s'arrêtant soudainement ne sont que deux exemples communs de telles situations. De plus, les perturbations dues aux glissements latéraux sont fréquemment observées chez les personnes âgées. Les articulations des membres inférieurs et du tronc ont moins de latitude de mouvement dans le plan frontal que dans le plan sagittal. En conséquence, lors d'une translation médio-latérale inattendue le système nerveux central (SNC) utilise probablement des stratégies compensatoires différentes du cas de la direction antéro-postérieure. Le but de cette étude était d'évaluer les stratégies compensatoires utilisées lors de perturbations perpendiculaires au plan du mouvement. Un vélo ergométrique modifié fut utilisé comme modèle de mouvements rythmiques; dans une telle situation, les effets de l'équilibre sont de beaucoup amoindris et les réactions compensatoires peuvent être attribuées à la perturbation du mouvement rythmique. Pour les fins de cette étude les sujets eurent à pédaler sous quatre conditions expérimentales différentes: dynamique active (DA), au cours de laquelle les sujets pédalaient à une fréquence de 1 Hz maintenue à l'aide d'un métronome et d'information présentée sur un écran d'ordinateur; dynamique passive (DP), au cours de laquelle les mouvements enregistrés sous la condition DA étaient reproduits à l'aide d'un moteur dynamométrique tandis que les sujets devaient simplement relaxer; statique active (SA), au cours de laquelle chaque sujet devait essayer de reproduire l'activité musculaire produite par leur soléaire sous la condition DA; statique passive (SP), au cours de laquelle les sujets devaient simplement maintenir chacune des positions du cycle de pédalage tout en relaxant. Des mouvements vers la gauche et vers la droite d'à peu près 1 g (9.8 ms-2) d'accélération furent appliqués aléatoirement à l'aide d'un cylindre électrique pendant une des quatre phases du cycle de pédalage: propulsion (P), récupération (R), transition PR, et transition RP. L'activité électromyographique (EMG) du soléaire (SOL), du médial du gastrocnémien (MG), du tibial antérieur (TA), du vaste latéral (VL), du biceps fémoral [chef court] (BF), et du tenseur du fascia lata (TFL) furent enregistrés et analysés. Les réponses EMG furent divisées en deux époques (E) selon la latence de la réponse:

Incidence of Dentinal Crack Formation Using ProTaper Universal and WaveOne Systems in Straight and Curved Root Canals

Introduction: This study aimed to compare dentinal micro crack formation following root canal instrumentation with ProTaper Universal (PTU) and WaveOne (WO) rotary systems in straight and curved root canals. Methods and Materials: One hundred mesiobuccal (MB) straight and curved canals of mandibular molars meeting inclusion criteria were divided into two control (n=10) and four experimental groups (n=20). After mounting the teeth and simulating the periodontal ligament, all the MB canals were coronally flared using Gates-Glidden drills #3 and 2 respectively. Then, in the experimental groups, the canals were instrumented with either PTU files (Sx, S1, S2, F1, F2), or Primary WO (25/0.08). Afterwards, roots were horizontally sectioned at 2, 4, and 6 mm from the apices, and evaluated under a microscope under 20× magnification. Data were analyzed with the Chi-Square and Kruskal-Wallis tests. The significance level was set at 0.05. Results: The control groups showed no cracks. There was no significant difference between the two systems in the straight root canals (P>0.05). But in the curved root canals, PTU produced significantly more cracks (P<0.05) with the complete crack type which was dominant (P=0.013) compared to WO. Conclusions: This in vitro study showed that in curved root canals, instrumentation with reciprocal WO system may be safer than full rotational PTU instruments regarding crack formation.Keywords: Crack; Dentin; Instrumentation; Reciprocating; Root Canal Preparation

Robot-assisted therapy for upper limb rehabilitation in individuals with stroke: effectiveness, role of environment, and evaluation of a novel "Assist-As-Asked" protocol

In order to determine the effectiveness of robot-assisted therapy (RT) in upper limb (UL) rehabilitation of stroke patients, we first systematically reviewed and analyzed the literature. We found that when the duration/intensity of conventional therapy (CT) is matched with that of the RT, no difference exists between the intensive CT and RT groups in terms of motor recovery, activities of daily living, strength, and motor control. However, depending on the stage of recovery, extra sessions of RT in addition to regular CT are more beneficial than regular CT alone in motor recovery of the hemiparetic shoulder and elbow of patients with stroke; the gains are similar to those that have been observed in intensive CT. It has been shown that stroke patients with mild-to-moderate UL motor impairment benefit from training with a virtual reality rehabilitation system. However, during robot-assisted movements, it remains to be determined whether movements made in a virtual environment are similar to those made in a physical environment. Thus, we examined the role of training environment, whether virtual or physical, on robot-assisted reaching movements in chronic stroke and healthy individuals, within a single session. Fifteen subjects participated in this study divided into three groups: 5 chronic stroke individuals able to perform a reaching task with no need for the robot assistance, 5 chronic stroke individuals who needed the robot assistance to complete the reaching task, and 5 healthy individuals. The task was to reach for six target buttons in two identical physical and virtual environments. The outcomes consisted of kinematic measures and a custom questionnaire to assess how participants perceived and experienced the reaching task in both environments. We found no differences between the two environments in terms of the outcome measures in any of the groups. We concluded that the choice of environment, whether physical or virtual, is not a key factor in designing a robot-assisted reaching protocol for stroke survivors. Finally, we conducted a proof-of-concept study to identify clinical benefits and potential adverse effects of a novel, custom-developed RT protocol, named "Assist-As-Asked", aiming at improving arm function of chronic stroke subjects with moderate-to-severe UL motor impairment and to investigate whether practicing in a physical or virtual environment would make any difference in the outcomes of interest. Four chronic stroke subjects participated in 10 half-hour sessions to practice reaching six targets in both virtual and physical environments. The robotic arm provided gravity support, and with the "Assist-As-Asked" paradigm, helped subjects to complete movements when they requested it. Kinematics of the reaching movements and the subjects' perception about the reaching practice in both environments were the primary outcome measures of interest. Change in scores of FMA-UE was the secondary outcome measure. Following the RT sessions, all the subjects noticeably improved their reaching performance, which was accompanied by 3-5 points improvement in FMA-UE score. There were no differences between the two environments in terms of kinematic measures even though subjects had different opinions about environment preference. We concluded that moderate-to-severe chronic stroke survivors may benefit from RT using the "Assist-As-Asked" paradigm. In designing an RT platform for moderate-to-severe chronic stroke survivors, the choice of environment, either physical or virtual, does not necessarily influence the outcome of therapy sessions.Afin de déterminer l'efficacité de la thérapie assistée par un robot (RT) dans la réadaptation du membre supérieur (MS) chez les patients ayant subi accident vasculaire cérébral (AVC), nous avons d'abord systématiquement analysé la littérature pour identifier des essais contrôlés randomisés portant sur l'utilisation d'appareils de robotique pour la réadaptation du MS des personnes ayant subi un AVC. Nous avons trouvé que lorsque la durée / intensité de la thérapie conventionnelle (TC) est comparée avec la RT, aucune différence n'existe en terme de récupération motrice, de performance dans les activités de la vie quotidienne, de force, et de contrôle moteur. Cependant, dépendamment de la phase de récupération, des séances supplémentaires de la RT en plus de la TC sont plus bénéfiques que la TC seule pour la récupération motrice de l'épaule et du coude des patients ayant subi un AVC; les bénéfices sont similaires à ceux observés en TC intensive. Il a été démontré que les patients ayant subi AVC avec un déficit moteur léger à modéré du MS bénéficient d'un entraînement avec un système de réadaptation en réalité virtuelle. Cependant, lors des mouvements assistés par robot, il reste à déterminer si les mouvements effectués dans un environnement virtuel sont similaires à ceux réalisés dans un environnement physique. Nous avons donc examiné le rôle de l'environnement, virtuel ou physique, sur les mouvements assistés par un robot. Quinze sujets ont participé à cette étude divisée en trois groupes: 5 individus atteints d'AVC chronique capables d'accomplir une tâche sans avoir besoin du robot, 5 individus atteints d'AVC chronique ayant besoin d'une assistance robotique pour accomplir la tâche et 5 individus en bonne santé. La tâche était d'atteindre six cibles dans deux environnements physiques et virtuels identiques. Les résultats comprenaient des mesures cinématiques et un questionnaire pour évaluer comment les sujets ont perçu et vécu la tâche d'atteinte dans les deux environnements. Nous n'avons trouvé aucune différence pour les résultats entre les deux environnements et entre les groupes. Nous avons conclu que le choix de l'environnement, qu'il soit physique ou virtuel, n'est pas un facteur important dans la conception d'un protocole d'assistance avec un robot pour les personnes ayant subi un AVC. Enfin, nous avons mené une étude pour identifier les avantages cliniques d'un nouveau protocole RT personnalisé, appelé «Assist-As-Asked». Ce protocole vise l'amélioration la fonction du MS chez des sujets ayant subi un AVC et une déficience motrice modérée à sévère du MS. De plus, nous avons examiné si la pratique dans un environnement physique ou virtuel avait un impact au niveau des mesures ciblées. Quatre sujets ayant subi un AVC ont participé à 10 séances d'une demi-heure. La tâche était de pratiquer l'atteinte de six cibles dans des environnements virtuels et physiques. Le bras robotisé aidait les sujets au moyen du paradigme «Assist-As-Asked» (assistance à effectuer des mouvements lorsqu'ils le demandaient). Les principales mesures étaient la cinématique des mouvements du bras et la perception des sujets de la pratique dans les deux environnements. Le changement dans les scores du FMA-UE était la mesure secondaire. Après les séances de RT, tous les sujets ont nettement amélioré leur performance au niveau des mouvements du bras, accompagné d'une amélioration de 3-5 points du score FMA-UE. Il n'y avait aucune différence entre les deux environnements pour les mesures cinématiques, même si les sujets avaient diverses préférence sur l'environnement. Nous pouvons conclure que les personnes ayant subi un AVC modéré à sévère pourraient bénéficier de la RT en utilisant le paradigme «Assist-As-Asked». En concevant un protocole de RT pour les individus avec un AVC chronique modéré à sévère, le choix de l'environnement, soit physique ou virtuel, n'influence pas le résultat des séances de thérapies

Clinical Education Stressors in Operating Room Students: A Qualitative Study

Objective. The aim of this study is to explain the stressors of the clinical environment from the perspective of operating room undergraduate students. Methods. The present study is a qualitative study of contractual content analysis type that was conducted in 2019 at Hamadan University of Medical Sciences. In this study, 10 undergraduate operating room students were selected by purposive sampling. Semi-structured interviews were used to collect data. Results. From the analysis of interviews, 4 main categories were extracted as the stressors of operating room students of Hamadan Paramedical School in clinical learning environment: the need to receive support from the clinical environment (Insufficient students’ skills in communicating with staff, Discrimination between paramedical students and residents, and Facilities available for training), lack of practical prerequisite skills (Contradiction between training and performance, and Lack of prerequisite knowledge for clinical practice), poor supportive and communication performance related to the instructor (Insufficient support of the instructor to the students against the medical staff, Evaluation criteria for instructors, and Treatment of instructor with students in presence of others), and psychological needs (Concerns about career prospects, Lack of motivational factors, and Lack of supportive counseling). Conclusion. The results of this study showed that Operating room students are faced with many stressors in the clinical learning environment. All stressors identified in this study affected the students’ learning in the clinical setting. Lack of support for students in the clinical environment, poor practical skills training, poor support and communication performance related to the instructor, and poor psychological support of students are the factors that cause operating room student stress in the clinical environment

Loneliness and internet addiction in students of Hamadan University of medical sciences

Introduction: This study intends to determine the relationship between loneliness and internet addiction in students of Hamadan University of medical sciences in 2013.Material and Methods: In this cross-sectional descriptive-analytic study, students of Hamadan University of medical sciences were research population that sample involved 130 people which have been selected through random sampling. To gather the data, Loneliness Scale and Internet Addiction Questionnaire was used as well as demographic variables questionnaire. To analyze the data SPSS was used.Results: The findings revealed the characteristics of the research population as follows: high internet addiction and relatively loneliness. Results showed significant relationship between the internet addiction and age, term and level of education, also factors such as marital status, gender and occupation have no significant relation with internet addiction. Analysis indicated there were no statistically significant differences between loneliness and age, term, level of education, marital status, gender and occupation.Discussion: Due to the relatively high rate of Internet addiction in the study population, the findings will be reported to relevant managers and officials, to be considered in planning future

Effect of Foreperiod Duration and Handedness on Simple and Choice Auditory Reaction Time Among the Older People

Objectives Cognitive functions such as reaction time undergo change with aging. Given the importance of preparation in response to reaction time in various life situations, this study aimed to examine the effect of various foreperiods (0.5, 1.5, 2.5, and 3.5 s), and handedness at the time of simple and choice auditory reaction time. Methods & Materials The current research followed a quasi-experimental methodology and was carried out using a self-made software. The study population comprised all old people living in Ahvaz City. Of them, 30 people were selected through purposive sampling method and allocated into two groups of right- and left-handed people. Each individual was randomly tested for simple and selective reaction with randomly chosen foreperiods. Results The findings demonstrated a significant difference (P<0.05) between the different periods, and between simple and choice reaction time. It means that short (0.5 and 1.5 s) foreperiods result in the increase of reaction time and that left-handed individuals are associated with shorter reaction times compared with their right-handed counterparts. Conclusion Since cognitive processing occurs slower in the elderly, it is recommended that foreperiods with very short durations be avoided when preparing elders for different motor skills. In addition, the dominance of the right hemisphere, which contains higher numbers of neurons, among the left-handed might lead them to possess lower reaction times compared with right-handed individuals.peerReviewe

Feasibility, Safety and Efficacy of a Virtual Reality Exergame System to Supplement Upper Extremity Rehabilitation Post-Stroke: A Pilot Randomized Clinical Trial and Proof of Principle

(1) Background: Increasing the amount of therapy time has been shown to improve motor function in stroke survivors. However, it is often not possible to increase the amount of therapy time provided in the current one-on-one therapy models. Rehabilitation-based virtual reality exergame systems, such as Jintronix, can be offered to stroke survivors as an adjunct to traditional therapy. The goal of this study was to examine the safety and feasibility of providing additional therapy using an exergame system and assess its preliminary clinical efficacy. (2) Methods: Stroke survivors receiving outpatient rehabilitation services participated in this pilot randomized control trial in which the intervention group received 4 weeks of exergaming sessions in addition to traditional therapy sessions. (3) Results: Nine subjects in the intervention and nine subjects in the control group completed the study. The intervention group had at least two extra sessions per week, with an average duration of 44 min per session and no serious adverse events (falls, dizziness, or pain). The efficacy measures showed statistically meaningful improvements in the activities of daily living measures (i.e., MAL-QOM (motor activity log-quality of movement) and both mobility and physical domains of the SIS (stroke impact scale) with mean difference of 1.0%, 5.5%, and 6.7% between the intervention and control group, respectively) at post-intervention. (4) Conclusion: Using virtual reality exergaming technology as an adjunct to traditional therapy is feasible and safe in post-stroke rehabilitation and may be beneficial to upper extremity functional recovery