Surgical Instrument Signaling Gesture Recognition Using Surface Electromyography Signals.

Surgical Instrument Signaling (SIS) is compounded by specific hand gestures used by the communication between the surgeon and surgical instrumentator. With SIS, the surgeon executes signals representing determined instruments in order to avoid error and communication failures. This work presented the feasibility of an SIS gesture recognition system using surface electromyographic (sEMG) signals acquired from the Myo armband, aiming to build a processing routine that aids telesurgery or robotic surgery applications. Unlike other works that use up to 10 gestures to represent and classify SIS gestures, a database with 14 selected gestures for SIS was recorded from 10 volunteers, with 30 repetitions per user. Segmentation, feature extraction, feature selection, and classification were performed, and several parameters were evaluated. These steps were performed by taking into account a wearable application, for which the complexity of pattern recognition algorithms is crucial. The system was tested offline and verified as to its contribution for all databases and each volunteer individually. An automatic segmentation algorithm was applied to identify the muscle activation; thus, 13 feature sets and 6 classifiers were tested. Moreover, 2 ensemble techniques aided in separating the sEMG signals into the 14 SIS gestures. Accuracy of 76% was obtained for the Support Vector Machine classifier for all databases and 88% for analyzing the volunteers individually. The system was demonstrated to be suitable for SIS gesture recognition using sEMG signals for wearable applications.

Analysis of Influence of Segmentation, Features, and Classification in sEMG Processing: A Case Study of Recognition of Brazilian Sign Language Alphabet.

Sign Language recognition systems aid communication among deaf people, hearing impaired people, and speakers. One of the types of signals that has seen increased studies and that can be used as input for these systems is surface electromyography (sEMG). This work presents the recognition of a set of alphabet gestures from Brazilian Sign Language (Libras) using sEMG acquired from an armband. Only sEMG signals were used as input. Signals from 12 subjects were acquired using a MyoTM armband for the 26 signs of the Libras alphabet. Additionally, as the sEMG has several signal processing parameters, the influence of segmentation, feature extraction, and classification was considered at each step of the pattern recognition. In segmentation, window length and the presence of four levels of overlap rates were analyzed, as well as the contribution of each feature, the literature feature sets, and new feature sets proposed for different classifiers. We found that the overlap rate had a high influence on this task. Accuracies in the order of 99% were achieved for the following factors: segments of 1.75 s with a 12.5% overlap rate; the proposed set of four features; and random forest (RF) classifiers.

Sensors and Systems for Physical Rehabilitation and Health Monitoring-A Review.

The use of wearable equipment and sensing devices to monitor physical activities, whether for well-being, sports monitoring, or medical rehabilitation, has expanded rapidly due to the evolution of sensing techniques, cheaper integrated circuits, and the development of connectivity technologies. In this scenario, this paper presents a state-of-the-art review of sensors and systems for rehabilitation and health monitoring. Although we know the increasing importance of data processing techniques, our focus was on analyzing the implementation of sensors and biomedical applications. Although many themes overlap, we organized this review based on three groups: Sensors in Healthcare, Home Medical Assistance, and Continuous Health Monitoring; Systems and Sensors in Physical Rehabilitation; and Assistive Systems.

Uptake, translocation, and control of trumpet flower (Tecoma stans) with aminocyclopyrachlor.

To gain a better understanding of the physiology of the herbicide aminocyclopyrachlor in young plants of trumpet flower, the uptake and translocation were evaluated after the application of herbicide. This was determined by treating individual leaves with formulated herbicides plus (14)C-aminocyclopyrachlor after the application of the formulated herbicide. This experiment used a randomized experimental design with three replications. In addition, field studies were conducted to assess the effectiveness of foliar applications of aminocyclopyrachlor in association with metsulfuton-methyl. The plant absorbed 20% of the herbicide applied. The translocation percentage did not surpass 5% of the total amount applied. Only 1% of the herbicide applied was translocated to the roots. Rate of 40 + 13 g a.i. 100 L(-1) of aminocyclopyrachlor+metsulfuron-methyl was effective to control T. stans.

Ethical and methodological challenges slowing progress in primary care-based suicide prevention: Illustrations from a randomized controlled trial and guidance for future research.

INTRODUCTION: Despite the pressing need for primary care-based suicide prevention initiatives and growing acknowledgement of recruitment difficulties and Institutional Review Board (IRB) challenges in suicide research, we are aware of no illustrative examples describing how IRB decisions in the design of a primary care trial can compound recruitment challenges. METHODS: The CDC-funded trial (NCT02986113) of Men and Providers Preventing Suicide aimed to examine the effects of a tailored computer program encourage men with suicidal thoughts (n = 304, ages 35-64) to discuss suicide with a primary care clinician and accept treatment. Before a visit, participants viewed MAPS or a non-tailored control video. Post-visit, both arms were offered telephone collaborative care, as mandated by the institutional review board (IRB). We previously showed that exposure to MAPs led to improvements in communication about suicide in a primary care visit. In this paper, we report data on the study's primary outcome, suicide preparatory behaviors. RESULTS: After screening nearly 4100 men, 48 enrolled. Recruitment challenges, which were exacerabted by an IRB mandate narrowing post-intervention patient management differences between trial arms, limited detection of the effects of MAPS on suicide preparatory behaviors. CONCLUSIONS: While primary care settings are key sites for suicide prevention trials, issues such as recruitment difficulties and overly restrictive IRB requirements may limit their utility. Methodological innovation to improve recruitment and ethical guidance to inform IRB decision-making are needed.