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Aim: Intense training of arm movements using robotic devices can help reduce impairments in stroke. Recent evidence indicates that independent training of individual joints of the arm with robots can be as effective as coordinated multi-joint arm training. This makes a case for designing and developing robots made for training individual joints, which can be simpler and more compact than the ones for coordinate multi-joint arm training. The design of such a robot is the aim of the work presented in this paper. Methods: An end-effector robot kinematic design was developed and the optimal robot link lengths were estimated using an optimization procedure. A simple algorithm for automatically detecting human limb parameters is proposed and its performance was evaluated through a simulation study. Results: A six-degrees-of-freedom end-effector robot with three actuated degrees-of-freedom and three non-actuated self-aligning degrees-of-freedom for safe assisted training of the individual joints (shoulder or elbow) of the human arm was conceived. The proposed robot has relaxed constraints on the relative positioning of the human limb with respect to the robot. The optimized link lengths chosen for the robot allow it to cover about 80% of the human limb’s workspace, and possess good overall manipulability. The simple estimation procedure was demonstrated to estimate human limb parameters with low bias and variance. Discussion: The proposed robot with three actuated and three non-actuated degrees-of-freedom has a compact structure suitable for both the left and right arms without any change to its structure. The proposed automatic estimation procedure allows the robot to safely apply forces and impose movements to the human limb, without the need for any manual measurements. Such compact robots have the highest potential for clinical translation

Purpose Staphylococcus aureus (S. aureus), Klebsiella pneumoniae (K. pneumoniae) and Streptococcus pneumoniae (S. pneumoniae) are among the pathogens detected during Hajj pilgrimage known to cause pneumonia. This study aims to evaluate the antibacterial activity of activated carbon cloth (ACC) with Ag+ impregnated with zinc oxide nanoparticles (ZnO NPs) against these pathogens. Design/methodology/approach ZnO NPs were impregnated into ACC-Ag+ via layer-by-layer (LbL) self-assembly. Scanning electron microscope (SEM) was used to observe the fine surface morphological details of the ACC-Ag+-ZnO sheets. Antibacterial activity of the ACC-Ag+-ZnO sheets was evaluated using the disk-diffusion susceptibility assay. Allergy patch test was done to evaluate allergic reactions of the ACC-Ag+-ZnO sheets on human skin. Findings SEM micrographs showed successful impregnation of ZnO NPs into the ACC-Ag+ sheets. Disk-diffusion susceptibility assay results of ACC-Ag+-ZnO sheets against S. aureus, K. pneumoniae and S. pneumoniae showed good antibacterial activity; with 1.82 ± 0.13 mm zone of inhibition for S. pneumoniae, at a ZnO concentration of 0.78 mg mL-1. No signs of human skin irritation were observed throughout the allergy patch test. Originality/value Results indicate that ACC-Ag+-ZnO sheets could potentially be embedded within surgical face masks (pilgrims’ preferred) to reduce the risks involved with the transmission of respiratory tract infections during and after mass gatherings (e.g. Hajj/Umrah, Olympics).

The six-phase asymmetrical induction motors (SPIMs) are employed for high power medium voltage drive due to its attractive features of reduced stator copper loss, lower torque pulsation, higher torque per ampere, and higher reliability. In this paper, analysis of carrier-comparison-based pulse width modulation (PWM) techniques namely sinusoidal PWM and double zero-sequence injection PWM are carried out from a space vector perspective. Furthermore, new space vector pulsewidth modulation (SVPWM) techniques are developed by modifying the switching sequences of carrier-based PWM techniques. A comprehensive analysis of these PWM techniques is carried out in terms of harmonic flux trajectories, squared harmonic flux, and harmonic distortion factor (HDF). As a result, modified SVPWM technique namely 6ΦSVM3 is found superior to aforesaid PWM techniques, which significantly reduces HDF and provides lower current total harmonic distortion (THD). The experimental results of aforementioned PWM techniques are obtained and verified from six phase asymmetrical induction motor fed by dual two-level 3ΦVSIs. This paper is also accompanied by a video file of experimental test setup recorded while 6ΦSVM2 is running on SPIM.

Background Studies in healthy elderly patients have shown the prevalence of autonomic dysfunction (AD) in the range of 20 to 30%. However, there is paucity in data pertaining to AD in the elderly in the Indian context. Objective To assess the prevalence of AD in the elderly irrespective of their comorbidity status. Methods A total of 141 elderly patients with or without comorbidities/symptoms of AD were included. Demographic and clinical details of the patients were recorded. Autonomic function tests (AFTs) such as deep breathing test, Valsalva ratio, orthostatic heart rate (OHR), isometric handgrip test, and orthostatic blood pressure were performed based on Ewing’s battery of tests. The sensitivity, specificity, positive predictive value, negative predictive value, and the accuracy of AFTs were evaluated. Results Most patients (n = 85) were aged between 60 and 69 years, with a male predominance (58.87%). Hypertension and diabetes mellitus were the most common comorbidities. Postural hypotension was the most common symptom of AD. With advancing age, symptoms of AD manifested significantly more. Overall, 73.8% of patients had AD, of whom 45.4% had early AD. Number of AD symptoms, glycated hemoglobin (HbA1c) level, and comorbid factors (diabetes and hypertension) were significantly associated with the results of AFTs (p p Conclusion The study concludes that age itself is an independent predictor of AD, which increases in severity if associated with comorbidities.

We present a case of tetralogy of Fallot (TOF) accompanied by a type II aorto-pulmonary window with severe pulmonary arterial hypertension in a pediatric patient. A successful repair of tetralogy of Fallot with trans-pulmonary patch closure of aorto-pulmonary window was done.

Assistive devices like Standing Wheelchairs (SWC) have remained out of reach of the economically underprivileged even before the pandemic-induced financial downturn, and more so now. This paper describes the mechanical design of a manual user-actuated SWC that is cost-effective (equivalent of USD 210 in India, ex-factory) and has special features that minimise user effort and accommodates varying body weights (50–110 kg) and dimensions (1.52–1.83 m height). The design includes a six-bar mechanism and spring balancing to optimise user effort during operation. The optimised gas spring incorporates adjustability to minimise each user’s force for sit-stand-sit transitions. The handle shape is ergonomically designed using kinematic analysis to provide convenient gripping positions for actuation. The design has been customised based on parametric studies to suit varying body weights. Overall, the SWC design provides standing functionality with ease of operation, safety locks, customisability, affordability, outdoor mobility and is aesthetically pleasing. Customisability and the low cost of the device would enhance the accessibility of the SWC to a larger group of eligible users.Implications for rehabilitationManual user-operated standing wheelchair design using a six-bar mechanismSpring balancing used to reduce user effort to self-lift to the standing positionKinematic analysis used to determine convenient handle location for user easeCustomisability for wide range of users to ensure correct posture, optimal effortDesign refined through multiple iterations using inputs from users and cliniciansDesign commercialised at an affordable cost, making it accessible to a larger population Manual user-operated standing wheelchair design using a six-bar mechanism Spring balancing used to reduce user effort to self-lift to the standing position Kinematic analysis used to determine convenient handle location for user ease Customisability for wide range of users to ensure correct posture, optimal effort Design refined through multiple iterations using inputs from users and clinicians Design commercialised at an affordable cost, making it accessible to a larger population

Additional file 1. Screenshots of Survey.

Only 1 in 10 people with disabilities can access assistive devices, underlining the critical need for low-cost assistive products. This paper describes the design evolution of a manual user-operated standing wheelchair (SWC), translating from prototype to product. The SWC design has been refined over 5 years through multiple iterations based on comments from user trials. The SWC product, Arise, provides standing functionality, facile outdoor mobility, affordability, customisability, and is aesthetically pleasing. A one-time fitting and training ensure optimal effort for operation, correct posture, and comfortable user experience. The SWC accommodates users of different sizes and body weights (up to 110 kg) and minimises user effort with the use of a gas spring. Incorporating discrete adjustments enables customisation while retaining the advantages of mass manufacturing, which is necessary for ensuring affordability. The SWC has been field-tested and well received by over 100 wheelchair users, and Arise was launched recently by the industry partner. It should be noted that RESNA cautions on the use of any standing device without medical consultation. Nevertheless, with appropriate dissemination and awareness, it is anticipated that the affordable SWC product, Arise, will immensely benefit the eligible users and make a difference in their quality of life.Implications for RehabilitationProvides standing functionality, outdoor mobility, affordability and customisabilityAccommodates users of different sizes and body weights in a mass-manufacturable designErgonomic design reduces net user effort during sit-to-stand, stand-to-sit activityDesign iterated and refined based on feedback from over 100 user trials Provides standing functionality, outdoor mobility, affordability and customisability Accommodates users of different sizes and body weights in a mass-manufacturable design Ergonomic design reduces net user effort during sit-to-stand, stand-to-sit activity Design iterated and refined based on feedback from over 100 user trials

Background Dizziness among elderly patients is primarily treated in emergency and primary care centers. However, the causes and comorbidities responsible for dizziness in the elderly may differ in tertiary health care centers. Objective To determine the subtypes of persistent dizziness and to evaluate the number of contributory causes of dizziness among elderly patients. Methods and materials This observational cross-sectional study comprised of 130 patients aged >60 years. A detailed history of existing comorbidities was obtained. A standardized comprehensive evaluation of all patients was done using an International Delphi procedure. Data from each patient was independently reviewed for major and contributory causes of dizziness. Chi square test was used to find the association between dizziness and various contributing factors. Results Presyncope was the most frequent dizziness subtype (71.5%). Majority of patients showed one dizziness subtype (54.6%) and three contributory causes of dizziness (40.6%). An adverse effect of drug was the most common contributory cause for dizziness (20%). The most frequent underlying cause of dizziness was noted to be cardiovascular disease (40%), followed by peripheral vestibular disease (22.3%) and neurological disease (19%). Sixty six percent of the patients were identified with more than one contributing cause for dizziness. Conclusion Primary care physicians need to anticipate that many elderly dizzy patients can have more than one cause of dizziness. A systematic and planned approach can help the clinician to effectively treat dizziness in the elderly.