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This paper introduces a lightweight bilateral underactuated upper limb exoskeleton (UULE) designed to assist chronic stroke patients with distal joint (Elbow-Wrist) impairments during bimanual activities of daily living (ADL). The UULE aims to assist patients in shoulder flexion/extension, elbow flexion/extension, forearm pronation/supination, and wrist flexion/extension. Notable features include (i) a cable-driven mechanism maintaining a lightweight structure (1.783 kg); (ii) passive joints conforming to less-impaired proximal joints, reducing restrictions on their movements; (iii) a compact design with passive ball joints enabling bilateral configuration for scapula protraction/retraction; and (iv) implementation of the master-slave joint assistance training strategy in an underactuated exoskeleton, achieving symmetric robot joint motion in bimanual ADL. Experiments with ten healthy subjects demonstrated the UULE's effectiveness by revealing significant reductions in muscle activity in a symmetric bimanual ADL task. These advancements address critical limitations of current exoskeletons, showcasing the UULE as a promising contribution to lightweight and effective robotic rehabilitation strategies for chronic stroke patients.
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This work compares the structure of industrially isolated lignin samples from kraft pulping and three alternative processes: butanol organosolv, supercritical water hydrolysis, and sulfur dioxide/ethanol/water fractionation. Kraft processes are known to produce highly condensed lignin, with reduced potential for catalytic depolymerization, whereas the alternative processes have been hypothesized to impact the lignin less. The structural properties most relevant to catalytic depolymerization are characterized by elemental analysis, quantitative 13 C and 2 D HQSCâ NMR spectroscopy, gel permeation chromatography, and thermogravimetric analysis. Quantification of the ß-O-4 ether bond content shows partial depolymerization, with all samples having less than 12 bonds per 100 aromatic units. This results in theoretical monomer yields of less than 5 %, strongly suggesting the alternative fractionation processes generate highly condensed lignin structures that are no more suitable for catalytic depolymerization than kraft lignin. However, the different thermal degradation profiles suggest there are physicochemical differences that could be leveraged in other valorization strategies.
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Solvent selection guides are crucial in chemical process design and development. Lignin from lignocellulosic biomass is a potentially attractive feedstock for sustainable chemical feedstocks. One approach would use a solvent to recover lignin prior to the traditional pulping process to make cellulose fibers: lignin value prior to pulping (LVPP). A solvent selection methodology for LVPP is presented herein that may be expanded for any proposed solvent for this process. Four screening categories are elucidated, providing metrics for 30 solvents across multiple molecular functional groups. Through performance, hazards and environment, cost and availability, and process-economics screens, the initial list of solvents is reduced to two top-tier candidates, 1,6 hexamethylenediamine and diethanolamine. 1-Methylpiperazine also emerged as a potential candidate. This solvent-selection methodology streamlines experimentation and provides promising candidates for LVPP. In addition to creating a tailored solvent selection guide, valuable biomass pretreatment data that may be utilized in different renewable applications are also presented.
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This was a quasi-experimental study to compare the effects of center-based training with home-based training on physical function, quality of life and fall incidence in older adults. Fifty older adults were recruited to receive exercise training for 6 months. Participants in the center-based group received training under supervision of a physiotherapist at the day training center. Those in the home-based group received training assisted by a care worker at home. The outcome measures were the Elderly Mobility Scale (EMS), Berg Balance Scale (BBS), Numeric Pain Rating Scale (NPRS), Short-form 12 (SF-12) and fall incidence. Assessments were performed on all participants before and after the 6-month intervention period. Center-based training supervised by a physiotherapist was found to have beneficial effects on physical function, quality of life and fall incidence while home-based training assisted by a care worker had no effect on physical condition and self-rated health status in community dwelling older adults. Service agents should provide center-based or home-based training to the ageing population in a user-friendly way with consideration of factors such as rehabilitation potential and accessibility of transportation.
Assuntos
Acidentes por Quedas/prevenção & controle , Idoso de 80 Anos ou mais/fisiologia , Terapia por Exercício/organização & administração , Serviços de Assistência Domiciliar , Educação Física e Treinamento , Acidentes por Quedas/estatística & dados numéricos , Idoso , Feminino , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Manejo da Dor , Aptidão Física , Equilíbrio Postural , Qualidade de VidaRESUMO
PURPOSE: To systematically review the characteristics, prevalence, evolution, and obstetric associations of retinal hemorrhages (RH) in newborns. METHODS: A systematic review, searching 10 databases (1970-2011), identified 45 studies, which underwent two independent reviews via the use of standardized critical appraisal. Studies meeting the following criteria were included: examination by an ophthalmologist, use indirect ophthalmoscopy, and first examination conducted within 96 hours of birth and before hospital discharge. RESULTS: Thirteen studies were included, representing 1,777 infants. The studies revealed that 25.6% of newborns born via spontaneous vaginal deliveries had RH. In contrast, infants delivered by vacuum extraction had a 42.6% rate of RH (OR, 2.75; 95% CI, 1.32-5.70), and infants delivered by double-instrument deliveries (forceps and vacuum) had a 52% rate of RH (OR, 3.27; 95% CI, 1.68-6.36). The hemorrhages are commonly bilateral (59%), of varying severity, from "mild" (22%-56%) to "severe" (18%-37%), and predominantly intraretinal and in the posterior pole. The majority of RH (83%) resolved within 10 days; isolated cases persisted to 58 days. CONCLUSIONS: Birth-related RH in infants occurs in one-quarter of normal deliveries and are far more common after instrumental deliveries. Commonly bilateral, they were predominantly intraretinal, posterior, resolved rapidly, and very rarely persisted beyond 6 weeks.
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Traumatismos do Nascimento/epidemiologia , Parto Obstétrico , Hemorragia Retiniana/epidemiologia , Bases de Dados Factuais , Humanos , Lactente , Recém-Nascido , Prevalência , Fatores de RiscoRESUMO
AIMS: To assess the practice of the use of an opaque intraocular lens (IOL) for intractable diplopia in the UK. METHODS: A questionnaire was sent to 892 consultant ophthalmologists in practice requesting information on the treatment of intractable diplopia with an opaque IOL. Respondents were asked whether they would consider using an opaque IOL for intractable diplopia. Information was gathered on the numbers of lenses implanted, the type of lens used, and whether the lens was implanted inside or outside the capsular bag. In addition, we asked for the causes of intractable diplopia, the success in eliminating diplopia, the use of postoperative pilocarpine, and whether postoperative surveillance was part of the follow-up protocol. RESULTS: Of the 481 completed questionnaires received, 72% would consider implanting an opaque IOL. A total of 48 surgeons had implanted 1 or more lenses. There were 97 patients who were implanted with an opaque IOL over the past 15 years. Strabismus, nerve palsies, and previous retinal detachment surgery with diplopia were the main indications. Pseudophakic lenses were used by 38 surgeons in the capsular bag, 6 used iris-supported phakic lenses, and 2 used phakic lenses in the anterior chamber angle. The use of postoperative pilocarpine was reported by 9 surgeons, and 6 surgeons used regular ultrasound fundal surveillance. Patients were reported to be completely asymptomatic at discharge by 31 surgeons, with 15 surgeons reporting patients who were still symptomatic postoperatively. Only 1 intraoperative complication was reported. CONCLUSIONS: An opaque IOL is a safe method for treating intractable diplopia. This survey confirms that its practice is widely accepted in the UK.
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Diplopia/cirurgia , Lentes Intraoculares , Vigilância da População , Privação Sensorial , Visão Binocular/fisiologia , Diplopia/epidemiologia , Diplopia/fisiopatologia , Seguimentos , Humanos , Prevalência , Desenho de Prótese , Resultado do Tratamento , Reino Unido/epidemiologiaRESUMO
Cardioviruses comprise a genus of picornaviruses that cause severe illnesses in rodents, but little is known about the prevalence, diversity, or spectrum of disease of such agents among humans. A single cardiovirus isolate, Saffold virus, was cultured in 1981 in stool from an infant with fever. Here, we describe the identification of a group of human cardioviruses that have been cloned directly from patient specimens, the first of which was detected using a pan-viral microarray in respiratory secretions from a child with influenza-like illness. Phylogenetic analysis of the nearly complete viral genome (7961 bp) revealed that this virus belongs to the Theiler's murine encephalomyelitis virus (TMEV) subgroup of cardioviruses and is most closely related to Saffold virus. Subsequent screening by RT-PCR of 719 additional respiratory specimens [637 (89%) from patients with acute respiratory illness] and 400 cerebrospinal fluid specimens from patients with neurological disease (aseptic meningitis, encephalitis, and multiple sclerosis) revealed no evidence of cardiovirus infection. However, screening of 751 stool specimens from 498 individuals in a gastroenteritis cohort resulted in the detection of 6 additional cardioviruses (1.2%). Although all 8 human cardioviruses (including Saffold virus) clustered together by phylogenetic analysis, significant sequence diversity was observed in the VP1 gene (66.9%-100% pairwise amino acid identities). These findings suggest that there exists a diverse group of novel human Theiler's murine encephalomyelitis virus-like cardioviruses that hitherto have gone largely undetected, are found primarily in the gastrointestinal tract, can be shed asymptomatically, and have potential links to enteric and extraintestinal disease.