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Characterizing left ventricle (LV) systolic function in the presence of an LV assist device (LVAD) is extremely challenging. We developed a framework comprising a deep neural network (DNN) and a 0D model of the cardiovascular system to predict parameters of LV systolic function. DNN input data were systemic and pulmonary arterial pressure signals, and rotation speeds of the device. Output data were parameters of LV systolic function, including end-systolic maximal elastance (Emax,lv), a variable essential for adequate hemodynamic assessment of the LV. A 0D model of the cardiovascular system, including a wide range of LVAD settings and incorporating the whole spectrum of heart failure, was used to generate data for the training procedure of the DNN. The DNN predicted Emax,lv with a mean relative error of 10.1%, and all other parameters of LV function with a mean relative error of

The United States Food and Drug Administration agency is encouraging to use modeling and simulation in medical device evaluation, in order to reduce reliance on animal models and human data, and reduce costs and speed innovation. To address this challenge various models and simulators have been developed that play the role of artificial/virtual patients. A previously elaborated in IBBE PAS a hybrid (hydro-computer) simulator was adapted to perform simulations of the left ventricular mechanical assistance by the intra-aortic balloon pump (IABP). To implement this, some hardware and software changes were made to the simulator, in particular the following functionalities were added: connecting a physical aorta model; variable aortic compliance by introducing a numerical capacitor into the hybrid circulatory model; a rigid tube model of the aorta with an orifice system to simulate IABP support. Static characteristics were measured for both physical models of the aorta (silicone tubes) and the model with a numerical capacitor. IABP assistance was simulated using the developed aortic model. The preliminary simulation results show that the system is behaving correctly. The effects of IABP mechanical assistance of the left ventricle observed in the simulator are consistent with clinical practice. The application for simulations of IABP mechanical assistance extends the whole IBBE PAS hybrid simulator functionalities in terms of the mechanical heart assistance simulations.

Background Freezing of gait (FOG) during gait initiation in people with Parkinson’s disease (PD) may be related to a diminished ability to generate anticipatory postural adjustments (APAs). Externally applied perturbations that mimic the desired motion of the body during an APA have been demonstrated to shorten and amplify APAs; however, no portable device has been tested. In this study, a portable powered ankle-foot orthosis (PPAFO) testbed was utilized to investigate the effect of mechanical assistance, provided at the ankle joint, on the APAs during gait initiation. Research question Does mechanical assistance provided at the ankle joint improve APAs during gait initiation in people with PD and FOG? Methods Thirteen participants with PD and FOG initiated gait across five test conditions: two self-initiated (uncued) conditions in walking shoes [Baseline-Shoes], and the PPAFO in unpowered passive mode [Baseline-PPAFOPassive]; three “go” cued conditions that included an acoustic tone with the PPAFO in unpowered passive mode [Acoustic + PPAFOPassive], the mechanical assistance from the PPAFO [PPAFOActive], and the acoustic tone paired with mechanical assistance [Acoustic + PPAFOActive]. A warning-cue preceded the imperative “go” cue for all the cued trials. Peak amplitudes and timings of the vertical ground reaction forces (GRFs) and center of pressure (COP) shifts from onset to toe-off were compared across conditions. Results Mechanical assistance significantly increased the peak amplitudes of the GRFs and COP shifts, reduced APA variability, and decreased the time to toe-off relative to the passive conditions. Significance These findings demonstrate the potential utility of mechanical assistance at the ankle joint (with or without an acoustic cue) as a method to generate more consistent, shortened, and amplified APAs in people with PD and FOG.

BACKGROUND The purpose of this study was to compare early and late survival among patients who have undergone heart transplantation (HTx) with a short-term mechanical assist device. METHODS This was an ambispective, single-center, consecutive study of patients undergoing urgent HTx for 5 years. Pediatric transplants, retransplants, and combined transplants were excluded. Forty-five patients were included. Four groups were analyzed: those with venoarterial extracorporeal membrane oxygenation (ECMO) implanted 10 days; patients classified as INTERMACS 2 to 3 with Levitronix Centrimag implanted; and those classified as INTERMACS 2 with Levitronix Centrimag implanted. Survival and the influence of orotracheal intubation (OI) at the time of transplantation were compared. RESULTS There were differences in in-hospital mortality (P = .03) and total mortality (P = .06). The groups with the highest risk for mortality were those who carried ECMO for >10 days before transplantation or those classified as INTERMACS 2 with Levitronix Centrimag implanted. In these groups, the need for posttransplant circulatory support was also greater (P = .04) as was the length of stay in critical care (P = .02). The need for OI during the days of care and until transplantation had a negative effect on survival in all groups (P < .1). CONCLUSIONS There are different risk subgroups among patients who are transplanted with a circulatory/ventricular assist device. The lowest mortality occurs when the days of ECMO implantation are

In the traditional sense, most of the aid has the characteristics of one-way free. With Europe's coming out of the haze of World War II and moving towards revival, most of the aid belongs to the two-way and mutually beneficial development, which is beneficial to both donors and recipients. Based on Durkheim's theory of organic unity and mechanical solidarity, the author tries to use organic aid and mechanical assistance to discuss China's assistance to Xinjiang.

The mechanical assistance provided by exoskeletons could potentially replace, assist, or rehabilitate upper extremity function in patients with mild to moderate shoulder disability to perform activities of daily living. While many exoskeletons are “active” (e.g. motorized), mechanically passive exoskeletons may be a more practical and affordable solution to meet a growing clinical need for continuous, home-based movement assistance. In the current study, we designed, fabricated, and evaluated the performance of a wearable, passive, cable-driven shoulder exoskeleton (WPCSE) prototype. An innovative feature of the WPCSE is a modular spring-cam-wheel system that can be custom designed to compensate for any proportion of the shoulder elevation moment due to gravity over a large range of shoulder motion. The force produced by the spring-cam-wheel system is transmitted over the superior aspect of the shoulder to an arm cuff through a Bowden cable. The results from mechanical evaluation revealed that the modular spring-cam-wheel system could successfully produce an assistive positive shoulder elevation moment that matched the desired, theoretical moment. However, when measured from the physical WPCSE prototype, the moment was lower (up to 30%) during positive shoulder elevation and higher (up to 120%) during negative shoulder elevation due primarily to friction. Even so, our biomechanical evaluation showed that the WPCSE prototype reduced the root mean square (up to 35%) and peak (up to 33%) muscular activity, as measured by electromyography, of several muscles crossing the shoulder during shoulder elevation and horizontal adduction/abduction movements. These preliminary results suggest that our WPCSE may be suitable for providing movement assistance to people with shoulder disability.

PURPOSE End-stage cardiac disease has resulted in an increased utilization of cardiac transplantation or long-term mechanical assistance to sustain life. Though left ventricular assist devices (LVAD) have revolutionized the treatment algorithm for these patients, these devices carry a substantial infection rate, ranging from 30% to 50%. We report our institution's experience with attempted flap salvage for infected and exposed LVADs. METHODS A retrospective review for all LVAD-related infections treated with flaps at our institution from 2010 to 2015. RESULTS Twenty flaps were performed in 15 patients during the study period. Average age was 54 years. There were 4 women and 11 men with average body mass index of 30.6. Surgery was indicated for LVAD motor or drive line exposure in the setting of infection in all cases. Rectus abdominus (n = 10), omentum (n = 6), pectoralis major (n = 3), and intercostal (n = 1) were used for coverage. Complications resulted in approximately 67% of cases including hematoma (n = 4), seroma (n = 3), cellulitis (n = 1), and total flap loss (n = 1). CONCLUSIONS Left ventricular assist devices are lifesaving interventions for patients with severe cardiac disease but are associated with a high rate of infectious complications over time. Although device coverage carries a high rate of complications, no devices required exchange due to infection or failed attempts at salvage.

Mechanical assistance on joint movement is generally beneficial; however, its effects on cooperative performance and muscle activity needs to be further explored. This study examined how motor performance and muscle activity are altered when mechanical assistance is provided during isometric force control of ramp-down and hold phases. Thirteen right-handed participants (age: 24.7 ± 1.8 years) performed trajectory tracking tasks. Participants were asked to maintain the reference magnitude of 47 N (REF) during isometric elbow flexion. The force was released to a step-down magnitude of either 75% REF or 50% REF and maintained, with and without mechanical assistance. The ramp-down durations of force release were set to 0.5, 2.5, or 5.0 s. Throughout the experiment, we measured the following: (1) the force output using load cells to compute force variability and overshoot ratio; (2) peak perturbation on the elbow movement using an accelerometer; (3) the surface electromyography (sEMG) from biceps brachii and triceps brachii muscles; and (4) EMG oscillation from the biceps brachii muscle in the bandwidth of 15-45 Hz. Our results indicated that mechanical assistance, which involved greater peak perturbation, demonstrated lower force variability than non-assistance (p 0.01), while EMG oscillation in the biceps brachii muscle from 15 to 45 Hz was increased (p 0.05). These findings imply that if assistive force is provided during isometric force control, the central nervous system actively tries to stabilize motor performance by controlling specific motor unit activity in the agonist muscle.

Automotive glass manufacturing entails a range of activities and requires, inter alia, bending and twisting, working in static positions, reaching away from the body, repetitive movements, handling heavy materials, use of body force, and exposure to noise. The study entailed the conducting of interviews with operatives at an automotive glass facility using a structured questionnaire. Selected findings include: bending or twisting the back, repetitive movements, and handling heavy materials predominated in terms of ergonomics problems encountered; things within easy reach, adjustable work surfaces, being able to sit down, elbow height work, and mechanical assistance, predominated in terms of the interventions that would make work easier, and the lower back, and both feet predominated in terms of the frequency at which pain occurs in an anatomical region as a result of use. Training of workers in positional work and working with load, investigating the ability to sit while working and worker participation in ergonomic solutions are selected recommendations.

Nowadays, the population of individuals managing bone-related challenges, such as bone damage and bone deterioration, among other related issues is escalating at an alarming rate. Studies are being conducted to aim at minimizing this population as the majority of surgical procedures such as allografts and autografts come with some limitations. As a result of challenges connected with autografts and allografts, metallic materials have been commonly utilized as internal scaffolding materials, particularly as a result of their highly required mechanical attributes. However, studies have revealed that metallic-based materials have limitations such as poor adherence, creep, stress-shielding, nondegradability, metallic-ion release, and challenges of biocompatibility with host tissues. Hence, quests for biomaterials suitable as bone-replacing alternatives providing required efficient scaffolds and three-dimensional biocompatibility capable of mimicking the attributes of the extracellular matrix of specific tissues, such as mechanical assistance and bioactivity, while facilitating an enabling environment for cellular adherence, variation, and proliferation, and for other internal supports have escalated. Thus scaffolds are often utilized in tissue engineering for facilitating regeneration of bones and other damaged tissues. These scaffolds must exhibit biodegradability and biocompatibility with the biomechanical properties of the bone. Therefore this chapter elucidates recent trends in polymeric materials and nanocomposites used in bone scaffold fabrication to overcome these challenges. Future market trends are also highlighted.

Refractory cardiogenic shock patients may be rescued by veno-arterial extracorporeal membrane oxygenation (VA ECMO). After a few days of mechanical assistance, the device can sometimes be successfully removed if the patient has partially or fully recovered from the condition that required the use of ECMO. The percentage of patients with refractory cardiogenic shock who are successfully weaned from ECMO varies from 31% to 76%. Weaning does not mean survival, because 20% to 65% of patients weaned from VA ECMO support do not survive to hospital discharge. The high death rate after successful weaning shows that many questions remain unresolved in this field. In this review, we will discuss the various factors influencing survival and a successful weaning from VA ECMO, in addition to weaning approaches proposed in the literature. Based on this information, we will propose a strategy to optimize the weaning process.

Motor performance patterns for mechanical assistance on unilateral force control can be affected by simultaneous muscle contraction. This study investigated how muscle activity and motor performance during the cooperation between dominant-arm force control and assistive force are affected by simultaneous non-dominant arm muscle contraction with inertial loading. Eleven participants (age: 24.1 ± 1.7 years) performed trajectory-tracking task based on visual feedback of real-time isometric force control. Their force for dominant-arm elbow flexion was released from reference magnitude of 47 N to magnitude of 23.5 N by providing mechanical assistance of a linear actuator. A 47 N of inertial loading on non-dominant arm elbow flexion was conditionally provided. For four time epochs of the experimental task, we measured responses of the assisted arm in terms of: (1) surface electromyography (EMG) amplitudes of biceps brachii and triceps brachii muscles, (2) peak perturbation, and (3) motor performance of force variability and target overshoot during manual force output. Simultaneous loading on unassisted arm did not affect peak perturbation of assisted arm. However, it caused lower force variability and overshoot ratio during the time epoch of force release and higher EMG amplitudes of biceps brachii muscle during the time epochs after mechanical assistance is provided, compared to the non-loaded condition. Our results indicate that simultaneous muscle contraction affects unilateral force control with mechanical assistance aimed at enhancing motor performance by creating extra agonist muscle activity. These findings can be utilized for improving the performance of human-robot cooperation during manual material handling in many industrial sites.

Hemiparetic gait after stroke is typically asymmetric and energetically inefficient. A major contributor to walking deficits is impaired paretic ankle function. Impaired paretic ankle plantarflexion (PF) reduces forward propulsion symmetry and impaired paretic ankle dorsiflexion (DF) diminishes ground clearance during swing. We have developed soft wearable robots (soft exosuits) to assist paretic PF and DF during walking after stroke. Through experimental studies with poststroke patients, we have demonstrated that exosuits can improve forward propulsion symmetry and ground clearance in walking, ultimately reducing the metabolic cost of walking. This paper presents an optimized soft exosuit aimed at use in clinical gait training for patients poststroke. The optimized exosuit is lightweight, easy to don and doff, and capable of efficiently delivering mechanical assistance to the paretic ankle. This paper focuses on the optimized controller that can deliver well-timed consistent ankle assistance to patients. A preliminary study was performed using this exosuit with three poststroke patients with heterogeneous gait patterns. Results showed that compared to a previously published controller, more consistent assistive force profiles could be delivered to individuals poststroke while consuming 50% less electrical power. Additionally, a preliminary biomechanical assessment was performed during overground walking.

Left ventricular assist devices (LVADs) have been developed to support end-stage heart failure patients. First-generation LVADs are volume displacement pumps, which function by mimicking the native heart and can be implanted intra-, extra-, or paracorporeally. These devices operate by periodically allowing blood to fill a pumping chamber followed by an ejection of blood from that chamber via pneumatic or electric actuation. Initial development of volume displacement pumps for post-cardiotomy support was undertaken in the 1960s. In 1978, the first patient was bridged to heart transplantation using a LVAD. Subsequently, commercial LVADs became available in the late 1980s and early 1990s. In 2001, the “Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) trial” established the efficacy of first-generation LVADs, finding that LVADs improved patient survival and quality of life compared to optimal medical management. Although commercially approved volume displacement pumps have demonstrated improved outcomes in comparison to medical therapy and deliver pulsatile flow, their durability, reliability, and reduced survival rates, in contrast to rotary blood pumps, have limited their use. Future considerations of volume displacement pumps have included flow optimization, valve design, and designing a cost-effective device.

There has been a progressive increase in the use of mechanical circulatory support in our country in the last years, mainly in the short-term: as a bridge to cardiac transplant or recovery, which has allowed to rescue patients from a population that concentrates high rates of complications and mortality. This motivated that the Ministry of Health convened a series of experts in the area of heart failure, transplantation and mechanical circulatory support, representatives of different public and private health centers in Chile, with the objective of developing recommendations on the use of short-term mechanical assistance devices, which would serve as a reference for the proper management of these patients. This clinical experts consensus document contains topics related to: definitions and general concepts; indications; contraindications; specific aspects of starting, follow-up and weaning of the devices; process of transfer of patients in circulatory assistance from one center to another and finally criteria of organization, means and competences to be fulfilled by the centers that offer this therapeutic option.

In patients with refractory cardiogenic shock (CS) mechanical assistance by venous-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy may be considered to reach haemodynamic stabilization. In this first-in-man study, we analysed the applicability of the new i-cor VA-ECMO assist device equipped with a diagonal pump system.In total, 15 patients with refractory CS were treated with the i-cor assist device in three tertiary care centres. In 71%, CS was due to acute myocardial infarction (AMI). At baseline, patients were hypotensive (systolic/diastolic blood pressure 97 ± 4/62 ± 4 mm Hg) despite high doses of catecholamines. Under ECMO therapy, a significant reduction in vasopressor therapy and serum lactate levels was observed (norepinephrine: 0.69 ± 0.1 µg/kg/min at baseline vs 0.21 ± 0.08 µg/kg/min on the last day of treatment, p0.0001; serum lactate: 6.7 ± 1.4 mmol/l at baseline versus 1.3 ± 0.1 mmol/l on the last day, p0.001). Inspiratory oxygen concentration was significantly reduced during the course of VA-ECMO support (80.4 ± 7.0% at baseline vs 42.7 ± 2.4% on final day; p0.001). At baseline, three patients (20%) were on continuous haemodialysis treatment. Of the 12 patients without haemodialysis at baseline, only one patient required haemodialysis during the course of ECMO treatment. Glomerular filtration rate (GFR) significantly increased with treatment (41.2 ± 7.4 at baseline vs 69.0 ± 10.8 on last day; p=0.006). Bleeding at the insertion site was recorded in two patients (13.3%). Overall, 11 patients (73.3%) needed blood transfusion. Three patients (20%) developed signs of limb ischaemia that were fully reversible. Haemolysis was recorded in five patients (33%). None of the complications required the interruption of ECMO therapy. Overall mortality was 33.3% (five patients); two patients died during, and three patients after, ECMO therapy.This first-in-man analysis suggests that the i-cor ECMO device is successfully applicable in humans. The data set the stage for further evaluation of this novel system and provide the necessary basis to design randomised evaluations.

Background: Mechanical assistance cough for patients with neuromuscular disorders (NMD) is commonly used, but there is no adaptation model established. Currently is performed subjectively by the physiotherapist following the pressures recommended in the current literature (LRP) as optimal (±40CmH 2 O). Aim: To check if LRP are the most optimal pressures to achieve the better peak cough flow (PCF). Method: Repeated measures study was performed to evaluate the effectiveness measured by PCF. Subjects adults with cough assist (CA) criteria (PCFbaseline 2 O (10 to 40cmH 2 O) and 4 adding expiratory pressures (±10 to ±40cmH 2 O). Results: Eighteen patients were included, 67% of them were diagnosed of Amyotrophic Lateral Sclerosis (ALS). High pressures (> ±35cmH 2 O) were the most optimal to achieve the best PCF by 50% of patients, 78% of them were ALS. The rest were achieved with low pressures ( 2 O), 55% of them were ALS. Statistically significant differences were found in the comparison between PCFbaseline and PCFmaximum (max) (p Conclusion: PCFmax obtained did not match always with the PCFL, for this, is advisable to perform CA adaptation individualized by monitoring in patients with NMD to improve the therapy.

In image-guided surgery, preoperative images are registered to an intraoperative tracking system and thereby provide visual feedback of the position of one or more surgical instruments with respect to the patient anatomy in the preoperative image. Two significant limitations of this approach are that relying on a preoperative image cannot account for registration error or intraoperative changes to the anatomy, and that the navigation system cannot provide mechanical assistance to the surgeon. We propose a system architecture to overcomeboth limitations by incorporating real-time image feedback in a telerobotic system that can provide guidance via virtual fixtures. We describe the implementation of this system, which integrates 3D Slicer and the da Vinci Research Kit (dVRK), and present a photoacoustic image-guided telerobotic system developed for endonasal skull base surgery as an example application.

Benign paroxysmal positional vertigo (BPPV) is one of the most common peripheral vestibular diseases. The aim of this study was to explore the prevalence of BPPV in vertigo patients and the characteristics of BPPV in diagnosis and repositioning using mechanical assistance maneuvers and to analyze and summarize the reasons showing these characteristics. Seven hundred and twenty-six patients with vertigo were enrolled in this study. All patients were inspected by TRV armchair (SYNAPSYS, model TRV, France). BPPV patients were identified by the examination results. The characteristics and results using TRV armchair in diagnosis and treatment of BPPV were compared and analyzed. Of 726 vertigo patients, 209 BPPV patients were diagnosed, including 58 men and 151 women, aged from 16 to 87 (mean 52.90 ± 11.93) years. There were significant differences in the proportion of BPPV in male and female vertigo patients (P = 0.0233), but no differences among all age groups (P = 0.3201). Of 209 BPPV patients, 208 cases were repositioned by TRV armchair and no one appeared to have otolithic debris relocated into another canal in the repositioning procedures. 202 cases (97.12 %) were successful and six cases (2.87 %) were effective. None of them failed. This study suggests that BPPV is one of the most common diseases in the young vertigo patients, just like that in the old ones. Female of the species has predilection for BPPV and the site of predilection is the right posterior semicircular canals (PC-BPPV). The results of repositioning are perfect using mechanical assistance maneuvers.

Pediatric mechanical circulatory support (MCS) has advanced tremendously over the last decade, with momentum building in the development and implantation of durable ventricular assist devices (VADs) in smaller children with increasingly complex anatomy. Despite these advancements, VAD support for children continues to lag behind support options for adults. The most obvious disparity is the limited number of devices suitable for children for both short- and long-term support. Thus, there has been burgeoning interest in developing devices specifically tailored to suit the unique needs of children. From a design perspective, pediatric VADs differ significantly from adult devices: they are required to support a wide range of patient sizes (from newborn to adolescence), to allow for the increased circulatory demand commensurate with growth, and to accommodate the anatomic and physiological heterogeneity of congenital heart disease. Beyond the challenges of designing and developing pediatric VADs, there are multiple barriers to the clinical evaluation of these devices because of the small number of children who require this level of support. Therefore, it is considered infeasible to test device safety and effectiveness through large randomized, controlled trials like the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH),1 a large adult study. Additionally, industry is disincentivized to invest the necessary resources in the research and development of pediatric-specific medical devices with applicability to such a narrow market population.2 In the United States, the Food and Drug Administration (FDA) is tasked with the responsibility of ensuring that medical devices marketed in the United States have met the requirements establishing the safety and effectiveness for use in humans to treat a specific condition. Many pediatric-specific medical devices, including VADs, fall under the category of a humanitarian use device.3 Humanitarian use devices are devices that are used to treat or diagnose …

Intra-aortic balloon pump counterpulsation is currently the most used mechanical assistance device for patients with cardiogenic shock due to acute myocardial infarction. However, a recently published meta-analysis and trial failed to confirm previous knowledge. We report the results of four patients with ST elevation myocardial infarction, complicated by cardiogenic shock unsuitable for intra-aortic balloon pump counterpulsation treated with early levosimendan infusion during primary percutaneous coronary intervention.

Paper-based devices provide an alternative technology for simple, low-cost, portable, and disposable or recyclable diagnostic tools for many applications, including clinical diagnosis, food quality control, and environmental monitoring. The present review focuses on new paper-based tests for point-of-care (POC) infectious disease testing. This review provides a brief presentation of the fabrication techniques and the main sample preparation procedures. Recent immunological and molecular testing formats based on new paper-based solutions which go beyond conventional lateral flow formats are also added. Emphasis is placed on how paper systems could be used for detecting whole and viable bacteria associated to infectious diseases. Paper has recently become attractive, since it is a ubiquitous and extremely cheap material. It is easy to store, easy to use, and is compatible with many (bio)chemical and (bio)medical applications. Paper absorbs and transports liquids by capillary force without additional mechanical assistance. Hence, paper-based analytical devices are promising and possibly game-changing, even if they still suffer from limitations, including accuracy and sensitivity. It is anticipated that, in the near future, with advances in fabrication procedures and associated analytical techniques, there will be a continuous flow of innovative paper-based diagnostics kits.

Background In clinical trials with time-to-event outcomes, it is common to design the interim analysis plan around the occurrence of designated target numbers of events. As the trial progresses, one may wish to use the accumulating data to predict the calendar times of these events as an aid to logistical planning. Purpose To demonstrate three models for the prediction of event times using the accumulating data of the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) Trial. Methods We apply three prediction models – an exponential model, a Weibull model, and a nonparametric model – to the evolving REMATCH data. Using Bayesian simulation methods, we predict the times of the designated landmark events and the end-of-study treatment effect, and calculate the predictive power. Results The models were practical to apply from an early stage of the trial, and gave largely similar predictions. Intervals from the nonparametric model were generally wider and more responsive to surges and droughts in events. Predictions made early in the trial were sensitive to the assumed prior on the accrual rate. Limitations The use of badly calibrated priors can lead to poor predictions. Conclusions Predictions of landmark event times in REMATCH were accurate and responded deftly to a strong shift in the treatment effect that occurred midway through the trial. The method can provide reliable guidance for clinical trial planning.

Lower-limb exoskeletons are a promising tool for restoring or augmenting locomotion performance. While engineering advances have led to marked improvements on the machine side of the human machine interface, fundamental aspects of the physiological response of the human user remain unknown—especially at the level of individual leg muscles. One complication is that it is difficult to make direct measurements from muscles in humans without being invasive. Here we offer a novel benchtop approach by introducing a ‘smart’ robotic interface into the framework of biological muscle-tendon work loop experiments in order to simulate the local dynamical environment muscles experience in vivo during locomotion with exoskeleton assistance. Using this framework we demonstrate that providing force in parallel with a muscle-tendon using an ‘exo-tendon’ can have unintended consequences, disrupting the ‘tuned’ spring-like mechanics of the underlying biological muscle tendon unit.

We describe the development of the spring-based orthosis approach (as exemplified by T-WREX and ArmeoSpring) to enhance upper-extremity movement therapy after neurologic injury. This approach is based around the concept of using springs to assist a patient in moving his or her weakened arm as he or she practices computerized movement tasks. This chapter first traces the development of spring orthoses for arm therapy within the context of the development of robot-assisted therapy. Then, this chapter evaluates the spring orthosis approach in light of recent evidence concerning the role of mechanical assistance, functional exercise, and computer gaming in promoting upper-extremity movement recovery after stroke. This evidence suggests a path forward toward simplified spring-based orthoses for home use. As an example, we discuss the design and initial testing of a simple lever-based spring orthosis, the Resonating Arm Exerciser.

Electrohydrodynamic atomization (EHDA) as a process of dispersion liquids by using electrodynamic forces without any mechanical assistance was applied as a technique for microencapsulation. By microencapsulation solid particles or liquid droplets (called core material) are captured within a solid or liquid envelope (shell) made of another, immiscible material. Via microencapsulation environment-sensitive core materials—like cultures, vitamins, flavors, dyes, enzymes, salts, sweeteners, lipids, acidulates, and nutrients—are protected by the shell, which allows the life of encapsulated products to be longer. Usually starch, gums, fats, waxes, oils, dextrans, polysaccharides, proteins, or glucoses are used as shell in electrohydrodynamic microencapsulation processes. The following EHD methods of microencapsulation are presented: electrospray drying, electrospray extrusion, electrospray coextrusion, electrospray mixing, electrospray cooling, submerged electrospray, and electrospray encapsulation in reactive gas. Various applications of this technology in food industry are discussed.

Enquadramento: A dor lombar é uma ocorrência bastante frequente, sobretudo em enfermeiros que trabalham em contexto hospitalar. As suas determinantes são variadas, podendo ser de cariz individual, psicossocial e profissional/organizacional. Objetivo: Identificar a prevalência e as determinantes da lombalgia em enfermeiros que trabalham em contexto hospitalar. Pretende-se ainda procurar relações entre os sintomas auto-referidos e a avaliação clínica de sinais, contribuindo para a prevenção. Método: Trata-se de um estudo transversal, descritivo-correlacional e quantitativo. Numa primeira fase foi aplicado um questionário sobre lombalgia a 135 enfermeiros de um hospital em Lisboa. Posteriormente foi realizada uma avaliação clínica a 48 desses enfermeiros. Resultados: Os resultados evidenciam uma elevada prevalência de lombalgia (60.7%) nos enfermeiros da amostra, estando esta associada a algumas variáveis sociodemográficas, organizacionais e profissionais. Destacam-se: o grupo etário (p=0.016), a altura (p=0.035), o trabalho por turnos (p=0.044) e o tempo de profissão (p=0.005). De forma análoga, o “posicionamento/mobilização do doente na cama” (p=0.026), o “levantar o doente da cama sem ajuda mecânica” (p=0.004), o “trabalho de pé” (65.9%), o “inclinar (86.6%) e rodar (76.8%) o tronco” e a “manipulação de cargas” (85.4%) revelaram-se influentes na dor lombar. Relativamente à avaliação clínica, dos enfermeiros avaliados (n=48), 89.6% referiram dor lombar com predominância de intensidade moderada (n=38), sendo que os sintomas se mantiveram desde a resposta ao questionário. Conclusões: Conclui-se, neste estudo, que a dor lombar assume especial relevância na profissão de enfermagem. A lombalgia dos enfermeiros que trabalham em meio hospitalar é não específica e apresenta caraterísticas mecânicas. Os fatores de risco relacionados com a atividade, presentes nas tarefas desempenhadas, são os que mais contribuem para a existência de lombalgia. Recomendam-se intervenções que se baseiem na avaliação dos fatores de prognóstico de cronicidade, de modo a evitar a evolução desfavorável da lombalgia e prevenir o aparecimento de novos casos., Gestão e Desenvolvimento, n. 24 (2016)

The study investigates the factors underlie risk and comfort in complex situations provided by adjustable care bed(ACB) in passive motion procedure, also quantified the influence of forces to comfort. Subjects simply trained took part in the measurement on three types of adjustable care beds, they experienced the passive motion process, then reflected their feeling and conducted the questionnaires. Motion limitation and influencing factors were defined according to reflection of subjects. Conclusions are drawn from results of quantified subtle influence of forces to define the motion limitation of ACB. A series of recommendations to improve passive motion of ACB were given, also to predict the feasibility of unprecedented functions or new postures provided by mechanical assistance to some extend.

Digital Image Correlation (DIC) is an ill-posed problem. To circumvent this difficulty, the needed regularization is often introduced implicitly through the choice of a kinematic basis used to embed the sought solution for displacement fields. Alternatively, a priori information on the mechanical behavior of the studied specimen is often available. This presentation is focused on different ways of supplementing DIC with mechanical information to achieve enhanced fidelity and robustness. Adapted unstructured mesh is used herein as an example of such a coupling.

Cardiogenic shock still has a grave prognosis. We present the recent advances in mechanical circulatory support (MCS) for the treatment of refractory cardiogenic shock.The contraindications for short-term MCS in rapid-onset cardiogenic shock are becoming fewer and the threshold for its application has been progressively lowered. Short-term MCS is increasingly used in refractory cardiac arrest and will be probably integrated as the last means in the advanced cardiopulmonary resuscitation algorithm (provided there is experienced team and technical support). Improved device technology has contributed to improved results of long-term MCS. Emergent application of long-term MCS in patients with critical cardiogenic shock after a long history of progressively deteriorating end-stage chronic heart failure should be interpreted as delayed application associated with increased mortality.Although MCS can be life saving in cardiogenic shock, the results are still suboptimal. Mortality is associated with the critical presupport state and the adverse events during MCS. Early initiation of support that meets the patient's requirements, potent support in the early phase, adverse event prevention, global combined management (surgical, interventional, medical), balanced support duration, bridging to further therapeutic modalities including heart transplantation or longer-term support, and advanced technology could offer improved results.