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1.
Artigo em Inglês | MEDLINE | ID: mdl-32900595

RESUMO

BACKGROUND: The Lokomat is a commercially available exoskeleton for gait training in persons with cerebral palsy (CP). Because active contributions and variability over movement repetitions are determinants of training effectiveness, we studied muscle activity in children with CP, and determined (i) differences between treadmill and Lokomat walking, and (ii) the effects of Lokomat training parameters, on the amplitude and the stride-to-stride variability. METHODS: Ten children with CP (age 13.2 ± 2.9, GMFCS level II(n = 6)/III(n = 4)) walked on a treadmill (±1 km/h; 0% bodyweight support(BWS)), and in the Lokomat (50% and 100% guidance; ±1 km/h and ±2 km/h; 0% and 50% BWS). Activity was recorded from Gluteus Medius (GM), Vastus Lateralis (VL), Biceps Femoris (BF), Medial Gastrocnemius (MG) and Tibialis Anterior (TA) of the most affected side. The averaged amplitude per gait phase, and the second order coefficient of variation was used to determine the active contribution and stride-to-stride variability, respectively. RESULTS: Generally, the amplitude of activity was lower in the Lokomat than on the treadmill. During Lokomat walking, providing guidance and BWS resulted in slightly lower amplitudes whereas increased speed was associated with higher amplitudes. No significant differences in stride-to-stride variability were observed between Lokomat and treadmill walking, and in the Lokomat only speed (MG) and guidance (BF) affected variability. CONCLUSIONS: Lokomat walking reduces muscle activity in children with CP, whereas altering guidance or BWS generally does not affect amplitude. This urges additional measures to encourage active patient contributions, e.g. by increasing speed or through instruction.

2.
Disabil Rehabil ; : 1-16, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32805152

RESUMO

BACKGROUND: Human movement, rehabilitation, and allied sciences have embraced their ambitions within the cycle of "RehabMove" congresses over the past 30 years. This combination of disciplines and collaborations in the Netherlands has tried to provide answers to questions in the fields of rehabilitation and adapted sports, while simultaneously generating new questions and challenges. These research questions help us to further deepen our understanding of (impaired) human movement and functioning, with and without supportive technologies, and stress the importance of continued multidisciplinary (inter)national collaboration. METHODS: This position stand provides answers that were conceived by the authors in a creative process underlining the preparation of the 6th RehabMove Congress. RESULTS: The take-home message of the RehabMove2018 Congress is a plea for continued multidisciplinary research in the fields of rehabilitation and adapted sports. This should be aimed at more individualized notions of human functioning, practice, and training, but also of performance, improved supportive technology, and appropriate "human and technology asset management" at both individual and organization levels and over the lifespan. CONCLUSIONS: With this, we anticipate to support the development of rehabilitation sciences and technology and to stimulate the use of rehabilitation notions in general health care. We also hope to help ensure a stronger embodiment of preventive and lifestyle medicine in rehabilitation practice. Indeed, general health care and rehabilitation practice require a healthy and active lifestyle management and research agenda in the context of primary, secondary, and tertiary prevention. IMPLICATIONS FOR REHABILITATION Continued multidisciplinary (international) collaboration will stimulate the development of rehabilitation and human movement sciences. Notions from "human and technology asset management and ergonomics" are fundamental to rehabilitation practice and research. The rehabilitation concept will further merge into general health care and the quality there-off.

3.
BMC Nephrol ; 21(1): 259, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641153

RESUMO

BACKGROUND: The impact of anemia treatment with erythropoietin stimulating agents (ESA) on health-related quality of life (HRQOL) in chronic kidney disease (CKD) patients is controversial, particularly regarding optimal hemoglobin (Hb) target ranges. METHODS: We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCT) with ESA to estimate the effect of different achieved Hb values on physical HRQOL and functionality. We searched PubMed, EMBASE, CENTRAL, PEDro, PsycINFO and Web of Science databases, until May 2020. Two authors independently extracted data from studies. We included observational and RCTs that enrolled CKD patients undergoing anemia treatment with ESA with different achieved Hb levels among groups. We excluded studies with achieved Hb < 9 g/dL. For the meta-analysis, we included RCTs with control groups achieving Hb 10-11.5 g/dL and active groups with Hb > 11.5 g/dL. We analyzed the standardized mean difference (SMD) between groups for physical HRQOL. RESULTS: Among 8496 studies, fifteen RCTs and five observational studies were included for the systematic review. We performed the meta-analysis in a subset of eleven eligible RCTs. For physical role and physical function, SMDs were 0.0875 [95% CI: - 0.0025 - 0.178] and 0.08 [95% CI: - 0.03 - 0.19], respectively. For fatigue, SMD was 0.16 [95% CI: 0.09-0.24]. Subgroup analysis showed that trials with greater achieved Hb had greater pooled effects sizes - 0.21 [95% CI: 0.07-0.36] for Hb > 13 g/dL vs. 0.09 [95% CI: 0.02-0.16] for Hb 11.5-13 g/dL. Proportion of older and long-term diabetic patients across studies were associated with lower effect sizes. CONCLUSION: Achieved hemoglobin higher than currently recommended targets may be associated with small but potentially clinically significant improvement in fatigue, but not in physical role or physical function. Younger and non-diabetic patients may experience more pronounced benefits of higher Hb levels after treatment with ESAs.

4.
J Antimicrob Chemother ; 75(9): 2666-2669, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32437580

RESUMO

BACKGROUND: Hepatic cyst infection is a complication of polycystic liver disease (PLD) that causes substantial morbidity. Repetitive infection is frequent and is increasingly difficult to treat. As translocated gut bacteria are considered the cause, we hypothesize that selective decontamination of the digestive tract (SDD) reduces recurrence of hepatic cyst infection. METHODS: We performed a retrospective, observational study in two referral centres. All patients with PLD treated with SDD for hepatic cyst infection were included. Efficacy was determined by calculating the infection incidence (hepatic cyst infections per month) before and during SDD therapy. Adverse events were scored according to the Common Terminology Criteria for Adverse Events (CTCAE). RESULTS: We identified eight patients who received SDD (88% female, 88% polycystic kidney disease). The median age was 65 years (IQR: 51-74 years). SDD lowered the median incidence from 0.09 episodes per month (IQR: 0.06-0.25 episodes per month) to 0.01 episodes per month (IQR: 0.00-0.05 episodes per month) (P = 0.12). Discontinuation of SDD led to rapid recurrence of cyst infection (71% within 6 weeks). SDD consisted of polymyxins with/without aminoglycosides. The median SDD treatment duration was 20 months (range: 3-89 months). Six patients (75%) developed adverse events [CTCAE Grade 1 (gastrointestinal: n = 3) or Grade 3 (ototoxicity: n = 1; fungal infection: n = 1)], mostly attributable to aminoglycosides; one patient developed polymyxin E resistance. CONCLUSIONS: SDD prophylaxis provides a novel strategy for limiting recurrent hepatic cyst infection in PLD patients. However, adverse events are frequent and curtail its use. As most were attributable to aminoglycosides, polymyxin E is considered the preferred therapy.

5.
Surgery ; 168(1): 25-32, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32402542

RESUMO

BACKGROUND: Polycystic liver disease can cause severe symptomatic hepatomegaly. Combined partial hepatectomy and cyst fenestration can be performed to reduce liver volume and symptom burden. We aimed to assess change in symptom relief and quality of life 6 months after partial hepatectomy and cyst fenestration in polycystic liver disease patients. METHOD: We established a prospective cohort between 2014 and 2018 at a referral center in the United States. Patients who underwent partial hepatectomy and cyst fenestration for volume-related symptoms were included. Primary outcome was change in polycystic liver disease-related symptoms, measured with Polycystic Liver Disease Questionnaire. Secondary outcomes were change in liver volume (computed tomography/ magnetic resonance imaging) and change in quality of life, measured with the 12-Item Short Form Survey and the EuroQoL Visual Analogue Scale. Questionnaire scores range from 0 to 100 and were assessed before and 6 months after partial hepatectomy and cyst fenestration. Surgical complications were scored according to Clavien-Dindo (grade 1 to 5). RESULTS: We included 18 patients (mean age 52 years, 82% female). Partial hepatectomy and cyst fenestration reduced median liver volume (4,917 to 2,120 mL). Symptoms, measured with Polycystic Liver Disease Questionnaire, decreased (76.9 to 34.8 points; P < .001) 6 months after surgery; 15/16 symptoms declined after treatment, with the most impact seen on early satiety and dyspnea. Quality of life also improved after surgery: median physical and mental component scales of the 12-Item Short Form Survey and EuroQoL Visual Analog Scale increased (24.9 to 45.7, P = .004; 40.5 to 55.4, P = .02; and 40.0 to 72.5, P = .003). Major complications (grade 4) occurred in 2 patients. There was no procedure-related mortality. CONCLUSION: Partial hepatectomy and cyst fenestration substantially improves symptom burden and quality of life in highly symptomatic polycystic liver disease patients.


Assuntos
Cistos/cirurgia , Hepatectomia/psicologia , Hepatopatias/cirurgia , Qualidade de Vida/psicologia , Adulto , Cistos/psicologia , Feminino , Hepatectomia/estatística & dados numéricos , Humanos , Hepatopatias/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
6.
Expert Opin Ther Targets ; 24(6): 589-599, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32250187

RESUMO

Introduction: Polycystic liver disease (PLD) is a rare disease defined by the growth of hepatic cysts and occurs either isolated or as an extrarenal manifestation of polycystic kidney disease. While surgery has been the mainstay in treatment of symptomatic PLD, recently discovered regulatory mechanisms affecting hepatic cystogenesis provide potential new therapies to reduce hepatic cyst burden.Areas covered: This review summarizes intracellular pathways and therapeutic targets involved in hepatic cystogenesis. While drugs that target cAMP, mTOR and bile acids were evaluated in clinical trials, investigation in autophagy, Wnt and miRNA signaling pathways are still in the pre-clinical phase. Recent epidemiological data present female hormones as a promising therapeutic target. Additionally, therapeutic advances in renal cystogenesis are reviewed for their potential application in treatment of hepatic cysts.Expert opinion: Further elucidation of the pathophysiology of hepatic cystogenesis is needed to provide additional targets and improve the efficacy of current treatments. The most promising therapeutic target in PLD is the female hormone pathway, given the increased severity in women and the harmful effects of exogenous estrogens. In addition, combining current pharmaceutical and surgical therapies can lead to improved outcomes. Lastly, the rarity of PLD creates the need to share expertise internationally.

7.
ANZ J Surg ; 90(5): 752-756, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32348031

RESUMO

BACKGROUND: Spread of technology and increased surveillance have led to more patients with lung cancers being identified than ever before. Increasingly, patients from the elderly population are referred for surgery; however, many studies do not focus on this patient group. We reviewed the outcomes of septuagenarians who underwent lobectomy via an open thoracotomy (OT) or video-assisted thoracoscopic surgery (VATS) approach to determine whether the VATS approach would result in superior post-operative outcomes. METHODS: Between January 2010 and June 2016, a total of 96 patients aged 70 years or older underwent a lobectomy for non-small cell lung carcinoma. Patients who underwent resection for metastatic disease, small cell lung cancer or neuroendocrine tumour were excluded. Demographic details, early and late post-operative outcomes including post-operative arrhythmia, myocardial infarction, respiratory failure, cerebrovascular events, infection, prolonged air leak, delirium, readmission and 30-day mortality were studied. Mean follow-up duration was 23 ± 19.1 months. RESULTS: Seventy-five patients underwent lobectomy via a VATS approach and 21 patients underwent lobectomy via an OT approach. There was no 30-day mortality and no difference in overall survival between the two techniques (P = 0.25). There was no significant difference between the two techniques with regard to post-operative stroke, myocardial infarction, atrial fibrillation, pneumonia, delirium or bronchopleural fistula. VATS patients had a significantly shorter mean hospital length of stay (VATS 4.7 days, OT 9.3 days, P = 0.005). CONCLUSION: Septuagenarians with non-small cell lung carcinoma can successfully undergo curative lung resection with a low incidence of post-operative complications.

9.
PLoS One ; 15(3): e0229756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126132

RESUMO

The aim of this work was to study the effect of a high sodium (HS) diet on blood pressure and renal function in male adult rats that have been treated with a dual Endothelin receptor antagonist (ERA) during their early postnatal period (day 1 to 20 of life). Male Sprague-Dawley rats were divided in four groups: CNS: control rats with normosodic diet; ERANS: ERA-treated rats with normosodic diet; CHS: control rats with high sodium diet; ERAHS: ERA-treated rats with HS diet. Systolic blood pressure (SBP) was recorded before and after the diet and 24-hour metabolic cage studies were performed. AQP2 and α-ENac expressions were measured by western blot and real time PCR in the renal medulla. Vasopressin (AVP) pathway was evaluated by measuring V2 receptor and adenylyl cyclase 6 (AC6) expression and cAMP production in the renal medulla. Pre-pro ET-1mRNA was also evaluated in the renal medulla. Only rats that had been treated with an ERA during their postnatal period increased their SBP after consumption of a HS diet, showing an impaired capacity to excrete sodium and water, i.e. developing salt sensitivity. This salt sensitivity would be mediated by an increase in renomedullary expression and activity of AQP2 and α-ENaC as a consequence of increased AC6 expression and cAMP production and/or a decreased ET-1 production in the renal medulla. The knowledge of the molecular mechanisms underlying the perinatal programming of salt sensitive hypertension will allow the development of reprogramming strategies in order to avoid this pathology.


Assuntos
Endotelinas/metabolismo , Hipertensão/etiologia , Medula Renal/crescimento & desenvolvimento , Receptores de Endotelina/metabolismo , Transdução de Sinais/fisiologia , Adulto , Animais , Animais Recém-Nascidos , Aquaporina 2/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Antagonistas dos Receptores de Endotelina/farmacologia , Endotelinas/antagonistas & inibidores , Canais Epiteliais de Sódio/metabolismo , Humanos , Hipertensão/fisiopatologia , Recém-Nascido , Medula Renal/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Eliminação Renal/efeitos dos fármacos , Eliminação Renal/fisiologia , Transdução de Sinais/efeitos dos fármacos , Cloreto de Sódio na Dieta/efeitos adversos , Cloreto de Sódio na Dieta/metabolismo , Vasopressinas/metabolismo
10.
J Vis Exp ; (156)2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32091009

RESUMO

The use of a manual wheelchair is critical to 1% of the world's population. Human powered wheeled mobility research has considerably matured, which has led to improved research techniques becoming available over the last decades. To increase the understanding of wheeled mobility performance, monitoring, training, skill acquisition, and optimization of the wheelchair-user interface in rehabilitation, daily life, and sports, further standardization of measurement set-ups and analyses is required. A crucial stepping-stone is the accurate measurement and standardization of external power output (measured in Watts), which is pivotal for the interpretation and comparison of experiments aiming to improve rehabilitation practice, activities of daily living, and adaptive sports. The different methodologies and advantages of accurate power output determination during overground, treadmill, and ergometer-based testing are presented and discussed in detail. Overground propulsion provides the most externally valid mode for testing, but standardization can be troublesome. Treadmill propulsion is mechanically similar to overground propulsion, but turning and accelerating is not possible. An ergometer is the most constrained and standardization is relatively easy. The goal is to stimulate good practice and standardization to facilitate the further development of theory and its application among research facilities and applied clinical and sports sciences around the world.


Assuntos
Fontes de Energia Elétrica , Cadeiras de Rodas , Fenômenos Biomecânicos , Calibragem , Teste de Esforço , Retroalimentação , Humanos
11.
Arch Phys Med Rehabil ; 101(6): 1017-1024, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32004518

RESUMO

OBJECTIVE: To investigate (1) changes in life satisfaction and mental health during 5 months of training for the HandbikeBattle and 4 months of follow-up; (2) associations between changes in handcycling cardiorespiratory fitness and changes in life satisfaction and mental health during the training period. DESIGN: This is a multicenter prospective cohort study with the following measurements: the start of the training (T1), after the 5-month training period, before the event (T2), and after 4 months of follow-up (T3). At T1, T2, and T3, questionnaires were filled out. At T1 and T2, a graded exercise test was performed to measure cardiorespiratory fitness (peak oxygen consumption [Vo2peak] and peak power output [POpeak]). SETTING: Ten Dutch rehabilitation centers training for the HandbikeBattle event. PARTICIPANTS: Patients with a rehabilitation history (N=136) and health conditions such as spinal cord injury, amputation, or multiple trauma history. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Life satisfaction as the sum score of 2 questions (range, 2-13) and the Mental Health subscale of the 36-item Short Form Health Survey (range, 0-100). RESULTS: Multilevel regression analyses showed that life satisfaction increased during the training period and did not significantly change during follow-up (mean ± SD, T1: 8.2±2.2; T2: 8.6±2.3; T3: 8.5±2.4). Mental health showed no change over time (T1: 77.7±14.5; T2: 77.8±14.5; T3: 75.7±16.5). An improvement in cardiorespiratory fitness was associated with an increase in life satisfaction (POpeak, ß=0.014, P=.046; Vo2peak, ß=1.068, P=.04). There were no associations between improvement in cardiorespiratory fitness and an increase in mental health (POpeak, P=.66; Vo2peak, P=.33). CONCLUSIONS: This study shows a positive course of life satisfaction during training for the HandbikeBattle. An improvement in cardiorespiratory fitness was longitudinally associated with an increase in life satisfaction. Mental health showed no changes over time.

12.
J Neuroeng Rehabil ; 17(1): 29, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093732

RESUMO

BACKGROUND: Originally, the cranks of a handcycle were mounted with a 180° phase shift (asynchronous). However, as handcycling became more popular, the crank mode switched to a parallel mounting (synchronous) over the years. Differences between both modes have been investigated, however, not into great detail for propulsion technique or practice effects. Our aim is to compare both crank modes from a biomechanical and physiological perspective, hence considering force and power production as a cause of physiological outcome measures. This is done within a practice protocol, as it is expected that motor learning takes place in the early stages of handcycling in novices. METHODS: Twelve able-bodied male novices volunteered to take part. The experiment consisted of a pre-test, three practice sessions and a post-test, which was subsequently repeated for both crank modes in a counterbalanced manner. In each session the participants handcycled for 3 × 4 minutes on a leveled motorized treadmill at 1.94 m/s. Inbetween sessions were 2 days of rest. 3D forces, handlebar and crank angle were measured on the left hand side. Kinematic markers were placed on the handcycle to monitor the movement on the treadmill. Lastly, breath-by-breath spirometry combined with heart-rate were continuously measured. The effects of crank mode and practice-based learning were analyzed using a two way repeated measures ANOVA, with synchronous vs asynchronous and pre-test vs post-test as within-subject factors. RESULTS: In the pre-test, asynchronous handcycling was less efficient than synchronous handcycling in terms of physiological strain, force production and timing. At the post-test, the metabolic costs were comparable for both modes. The force production was, also after practice, more efficient in the synchronous mode. External power production, crank rotation velocity and the distance travelled back and forwards on the treadmill suggest that asynchronous handcycling is more constant throughout the cycle. CONCLUSIONS: As the metabolic costs were reduced in the asynchronous mode, we would advise to include a practice period, when comparing both modes in scientific experiments. For handcycle users, we would currently advise a synchronous set-up for daily use, as the force production is more effective in the synchronous mode, even after practice.

13.
Mar Environ Res ; 155: 104879, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32072983

RESUMO

In the absence of instrumental records, shell growth increments of bivalves are used to build continuous multi-decadal time series of growth and to estimate environmental variability. While there is interest in such chronologies in the Northern Hemisphere, there is a lack of multi-decadal datasets of growth for marine species from the Southern Hemisphere. We assessed the potential of the clam Glycymeris longior as an environmental proxy archive for the mid-latitudes of the South Atlantic Ocean, by applying sclerochronological techniques on the shells of individuals from a coastal area in Northern Patagonia, Argentina. Growth of G. longior showed a synchronous pattern, and shells were cross dated. We demonstrated that G. longior shells can be used to generate a robust multi-decadal chronology. The chronology spanned for a period of 22 years, from 1990 to 2011. This chronology has the potential to be extended, given that the maximum longevity of the analysed shells was 69 years. Significant positive correlations were found between the chronology and sea surface temperature and the Southern Annular Mode index. The sclerochronological approach performed in this study is a first step toward a long-term understanding of the links between climate and growth patterns of bivalves in temperate regions of SW Atlantic Ocean, under a long-term perspective.


Assuntos
Bivalves/crescimento & desenvolvimento , Clima , Monitoramento Ambiental , Animais , Argentina , Oceano Atlântico
14.
Eur Arch Otorhinolaryngol ; 277(2): 343-350, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31650350

RESUMO

PURPOSE: In cochlear implantation (CI), the two factors that are determined by the surgeon with a potential significant impact on the position of the electrode within the cochlea and the potential outcome, are the surgical technique and electrode type. The objective of this prospective study was to evaluate the position of the slim, perimodiolar electrode (SPE), and to study the influence of the SPE position on CI outcome. METHODS: Twenty-three consecutively implanted, adult SPE candidates were included in this prospective cohort study conducted between December 2016 and April 2019. Mean age at surgery was 59.5 years. Mean preoperative residual hearing was 92.2 dB. Intra-operative fluoroscopy and high-resolution computed tomography scans were performed to evaluate electrode position after insertion using a cochleostomy (CS) approach. Follow-up was 12 months after implantation; residual hearing (6-8 weeks) and speech perception (6-8 weeks and 12 months) were evaluated in relation to the intracochlear SPE position. RESULTS: In most patients in whom the SPE was positioned in the scala tympani residual hearing was preserved [mean absolute increase in PTA of 4.4 dB and 77.2% relative hearing preservation (RHP%)]. Translocation into the scala vestibuli occurred in 36% of the insertions, resulting in a mean absolute increase in PTA of 17.9 dB, and a RHP% of 19.2%. Participants with a translocation had poorer speech perception scores at 12-month follow-up. CONCLUSION: Given the incidence of CS-associated translocations with the SPE and the negative effect on outcome, it is advised to insert the SPE using the (extended) round window approach.

15.
IEEE Rev Biomed Eng ; 13: 199-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31675342

RESUMO

There are many ways to simulate handrim wheelchair propulsion in the laboratory. Ideally, these would be able to, at least mechanically, simulate field conditions. This narrative review provides an overview of the lab-based equipment used in published research and critically assesses their ability to simulate and measure wheelchair propulsion performance. A close connection to the field can only be achieved if the instrument can adequately simulate frictional losses and inertia of real-life handrim wheelchair propulsion, while maintaining the ergonomic properties of the wheelchair-user interface. Lab-based testing is either performed on a treadmill or a wheelchair ergometer (WCE). For this study WCEs were divided into three categories: roller, flywheel, and integrated ergometers. In general, treadmills are mechanically realistic, but cannot simulate air drag and acceleration tasks cannot be performed; roller ergometers allow the use of the personal wheelchair, but calibration can be troublesome; flywheel ergometers can be built with commercially-available parts, but inertia is fixed and the personal wheelchair cannot be used; integrated ergometers do not employ the personal wheelchair, but are suited for the implementation of different simulation models and detailed measurements. Lab-based equipment is heterogeneous and there appears to be little consensus on how to simulate field conditions.

16.
Opt Express ; 27(23): 33586-33605, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878424

RESUMO

A new optimization method based on the topological derivative concept is developed for the electromagnetic design problem. Essentially, the purpose of the topological derivative method is to measure the sensitivity of a given shape functional with respect to a singular domain perturbation, so that it has applications in many relevant fields such as shape and topology optimization for imaging processing, inverse problems, and design of metamaterials. The topological derivative is rigorously derived for the electromagnetic scattering problem and used as gradient descent direction to find local optima for the design of electromagnetic devices. We demonstrate that the resulting topology design algorithm is remarkably simple and efficient and naturally leads to binary designs, while depending only on the solution of the conventional finite element formulation for electrodynamics. Finally, several numerical experiments in two and three spatial dimensions are presented to illustrate the performance of the proposed formulation.

17.
Disabil Rehabil ; : 1-14, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31656102

RESUMO

Purpose: To investigate changes in wheelchair propulsion technique and mechanical efficiency across first five weeks of active inpatient spinal cord injury rehabilitation and to compare the outcomes at discharge with experienced wheelchair users with spinal cord injury. Methods: Eight individuals with recent spinal cord injury performed six weekly submaximal exercise tests. The first and last measurement additionally contained a wheelchair circuit and peak graded exercise test. Fifteen experienced individuals performed all above-mentioned tests on one occasion. Results: Mechanical efficiency and propulsion technique did not change during the five weeks of inpatient rehabilitation. Peak power output during peak graded test and performance time on the wheelchair circuit improved between the first and the last week. No difference in propulsion technique, peak power output, and performance time was found between the persons with a recent injury and the experienced group. Mechanical efficiency was higher after the correction for the difference in relative power output in the experienced group. Conclusion: The group with a recent injury did not improve mechanical efficiency and propulsion technique over the period of active rehabilitation, despite significant improvements on the wheelchair circuit and in work capacity. The only significant difference between the groups was found in mechanical efficiency. Implications for rehabilitation The lack of time-dependent changes in mechanical efficiency and propulsion technique in the group with a recent spinal cord injury, combined with the lack of differences in technique, work capacity and on the wheelchair circuit between the groups, suggest that important adaptations of motor learning may happen even earlier in rehabilitation and emphasize that the group in active rehabilitation was relatively skilled. Standardized observational analyses of handrim wheelchair propulsion abilities during early spinal cord injury rehabilitation provide detailed understanding of wheelchair technique, skill as well as wheelchair propulsion capacity. Measurement of external power output is critical to interpretation of gross efficiency, propulsion technique, and capacity. Wheelchair quality and body weight - next to wheelchair fitness and skill - require careful consideration both in early rehabilitation as well as in the chronic phase of spinal cord injury.

18.
Inorg Chem ; 58(21): 14498-14506, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31621305

RESUMO

Achieving fine control on the structure of metal-organic frameworks (MOFs) is mandatory to obtain target physical properties. Herein, we present how the combination of a metalloligand approach and a postsynthetic method is a suitable and highly useful synthetic strategy to success on this extremely difficult task. First, a novel oxamato-based tetranuclear cobalt(III) compound with a tetrahedron-shaped geometry is used, for the first time, as the metalloligand toward calcium(II) metal ions to lead to a diamagnetic CaII-CoIII three-dimensional (3D) MOF (1). In a second stage, in a single-crystal-to-single-crystal manner, the calcium(II) ions are replaced by terbium(III), dysprosium(III), holmium(III), and erbium(III) ions to yield four isostructural novel LnIII-CoIII [Ln = Tb (2), Dy (3), Ho (4), and Er (5)] 3D MOFs. Direct-current magnetic properties for 2-5 show typical performances for the ground-state terms of the lanthanoid cations [7F6 (TbIII), 6H15/2 (DyIII), 5I8 (HoIII), and 4I15/2 (ErIII)]. Analysis of the χMT data indicates that the ground state is the lowest MJ value, that is, MJ = 0 (2 and 4) and ±1/2 (3 and 5). Kramers' ions (3 and 5) exhibit field-induced emergent frequency-dependent alternating-current magnetic susceptibility signals, which is indicative of the presence of slow magnetic relaxation typical of single-molecule magnets.

19.
Disabil Rehabil ; : 1-12, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31622120

RESUMO

Purpose: This study aimed to evaluate the implementation of a physical activity counseling program in rehabilitation and to study heterogeneity in received counseling and investigate its association with changes in patients' physical activity outcomes. Methods: This prospective cohort study was conducted in 18 rehabilitation institutions. Data were collected using surveys completed by professionals (n= ±70) and patients (n = 1719). Implementation was evaluated using different process outcomes: reach, dosage, satisfaction, maintenance. Patients' physical activity outcomes included changes in total minutes/week of physical activity. Latent class analyses were conducted to identify profiles of received counseling characteristics and multilevel models were used to investigate associations with physical activity outcomes. Results: 5873 Patients were provided with motivational interviewing-based counseling after rehabilitation. Professionals and patients were positive about the program. Sixteen institutions (89%) formally agreed to continue the program. The four identified profiles of counseling characteristics illustrate a large variation in received counseling among patients. No substantial differences in physical activity outcomes were found between profiles. Conclusion: After a three-year program period, the physical activity counseling centers were sustainably implemented in Dutch rehabilitation care. This study illustrated an innovative approach to assess heterogeneity in implementation outcomes (e.g., counseling profiles) in relation to program outcomes (e.g., physical activity). Implications for rehabilitation Physical activity counseling after rehabilitation is important to support people with disabilities in making the step from rehabilitation-based physical activities to community-based physical activities. Establishing "Physical Activity Counseling Centers" is a promising "disability-overarching" strategy to promote physical activity after rehabilitation. Although the actual received counseling (dosage) varied among patients, this did not coincide with large differences in physical activity outcomes. The training in Motivational Interviewing, the financial incentives, and the advisory support were considered as important or essential ingredients for a successful implementation of the counseling program in rehabilitation practice.

20.
BMJ Open ; 9(9): e031738, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31537574

RESUMO

INTRODUCTION: The rising prevalence of modifiable risk factors (eg, obesity, hypertension and physical inactivity) is causing an increase in possible avoidable complications in patients undergoing cardiac surgery. This study aims to assess whether a combined preoperative and postoperative multidisciplinary cardiac rehabilitation (CR) programme (Heart-ROCQ programme) can improve functional status and reduce surgical complications, readmissions and major adverse cardiac events (MACE) as compared with standard care. METHODS AND ANALYSIS: Patients (n=350) are randomised to the Heart-ROCQ programme or standard care. The Heart-ROCQ programme consists of a preoperative optimisation phase while waiting for surgery (three times per week, minimum of 3 weeks), a postoperative inpatient phase (3 weeks) and an outpatient CR phase (two times per week, 4 weeks). Patients receive multidisciplinary treatment (eg, physical therapy, dietary advice, psychological sessions and smoking cessation). Standard care consists of 6 weeks of postsurgery outpatient CR with education and physical therapy (two times per week). The primary outcome is a composite weighted score of functional status, surgical complications, readmissions and MACE, and is evaluated by a blinded endpoint committee. The secondary outcomes are length of stay, physical and psychological functioning, lifestyle risk factors, and work participation. Finally, an economic evaluation is performed. Data are collected at six time points: at baseline (start of the waiting period), the day before surgery, at discharge from the hospital, and at 3, 7 and 12 months postsurgery. ETHICS AND DISSEMINATION: This study will be conducted according to the principles of the Declaration of Helsinki (V.8, October 2013). The protocol has been approved by the Medical Ethical Review Board of the UMCG (no 2016/464). Results of this study will be submitted to a peer-reviewed scientific journal and can be presented at national and international conferences. TRIAL REGISTRATION NUMBER: NCT02984449.

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