Background and purpose: The aim of this study was to evaluate heterotopic ossification (HO) prevalence after stroke, describing clinical features and investigating predictors of HO and its severity. ...Methods: A cross-sectional study was carried out in 7 rehabilitation centers (Sarah Network) from 2004 to 2013. Results: Among 17,794 stroke cases, 235 patients (1.3%) presented clinical and radiological evidence of HO. A log-binomial model with robust variance estimated the prevalence ratio of 1.3% in 10 years. A multinomial logistic regression was performed to investigate the predictors of HO and its severity. The presence of hemorrhagic stroke (prevalence ratio PR = 4.75; 95% confidence interval CI PR = 3.38; 6.68) and ischemic stroke with hemorrhagic transformation (PR = 3.08; 95% CI PR = 1.63; 5.81), male sex (PR = 1.60; 95% CI PR = 1.16; 2.22), spasticity (PR = 13.78; 95% CI PR = 8.59; 22.10), and cognitive impairment (PR = 1.88; 95% CI PR = 1.36; 2.60) were independently associated with HO. Patients with HO were younger (P < .0001) and presented a shorter time of disease (P = .013). Young adult patients were more likely to develop severe HO (odds ratio = 2.80, 95% CI 1.09; 7.20) than were elderly patients. Severe HO was also related to heavy alcohol consumption (2.45; 1.03-5.84) and involved 2 or more joints (5.34; 1.85-15.36). There was an association with use of invasive ventilation (6.30; 2.13-18.63) at the acute stroke phase and patients were dependent on activities of daily living after stroke (3.90; 1.00-15.19). Conclusions: Despite the small prevalence of HO after stroke, this 10-year multicenter study was able to identify several associated factors related to the management and severity of stroke as well as the hemorrhagic subtype.
The dynamics of the positive ions created by particle interactions inside argon time projection chambers plays an important role in characterizing the next generation of massive detectors planned for ...the direct search for dark matter and the study of neutrino properties. We have constructed a 1 L liquid argon chamber (ARION: ARgon ION experiment) with a high voltage pulse generator capable of injecting, in a controlled manner, a sizeable ion current into the drift region. This chamber is capable of reproducing a volume charge similar to that found in large detectors, allowing its effects to be studied systematically. New experimental results regarding ion dynamics in the liquid and direct demonstration of ion feedback from the gas to the liquid are discussed in this paper. In addition, a novel technique to measure the drift velocity of argon ions is introduced along with preliminary results obtained in gas.
The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist ...to perform the most appropriate diagnostic tests.
To report the relative frequency of common neuromuscular diagnoses in a reference center.
A 17-year chart review of patients with suspicion of myopathy.
Among 3,412 examinations, 1,603 (46.98%) yielded confirmatory results: 782 (48.78%) underwent molecular studies, and 821 (51.21%) had muscle biopsies. The most frequent diagnoses were: dystrophinopathy 460 (28.70%), mitochondriopathy 330 (20.59%), spinal muscular atrophy 158 (9.86%), limb girdle muscular dystrophy 157 (9.79%), Steinert myotonic dystrophy 138 (8.61%), facioscapulohumeral muscular dystrophy 99 (6.17%), and other diagnoses 261 (16.28%).
Using the presently-available diagnostic techniques in this service, a specific limb girdle muscular dystrophy subtype diagnosis was reached in 61% of the patients. A neuromuscular-appropriate diagnosis is important for genetic counseling, rehabilitation orientation, and early treatment of respiratory and cardiac complications.
•Proposal of a minimalist parallel method for computing geodesic distances on meshes, and easy to implement.•No heavy pre-processing steps are required.•Yields quite good accuracy results even ...without preprocessing obtuse triangles.•It is able to solve the problem for very large meshes, regular and irregular.•Can be used with both single and double precision configurations.•Produces speedup results comparable to the state-of-art methods, or better, in some cases.
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The computation of geodesic distances is an important research topic in Geometry Processing and 3D Shape Analysis as it is a basic component of many methods used in these areas. In this work, we present a minimalistic parallel algorithm based on front propagation to compute approximate geodesic distances on meshes. Our method is practical and simple to implement, and does not require any heavy pre-processing. The convergence of our algorithm depends on the number of discrete level sets around the source points from which distance information propagates. To appropriately implement our method on GPUs taking into account memory coalescence problems, we take advantage of a graph representation based on a breadth-first search traversal that works harmoniously with our parallel front propagation approach. We report experiments that show how our method scales with the size of the problem. We compare the mean error and processing time obtained by our method with such measures computed using other methods. Our method produces results in competitive times with almost the same accuracy, especially for large meshes. We also demonstrate its use for solving two classical geometry processing problems: the regular sampling problem and the Voronoi tessellation on meshes.
A study of the dynamics of the positive charges in liquid argon has been carried out in the context of the future massive time projection chambers proposed for dark matter and neutrino physics. Given ...their small mobility coefficient in liquid argon, the ions spend a considerably longer time in the active volume with respect to the electrons. The positive charge density can be additionally increased by the injection, in the liquid volume, of the ions produced by the electron multiplying devices located in gas argon. The impact of the ion current on the uniformity of the field has been evaluated as well as the probability of the charge signal quenching due to the electron–ion recombination along the drift. The study results show some potential concerns for massive detectors with drift of many meters operated on surface.
During 12 months of follow-up in a randomized double-blind controlled field study, a killed whole-promastigote vaccine cocktail plus bacille Calmette-Guérin (BCG) adjuvant significantly reduced the ...incidence of cutaneous leishmaniasis (CL) in Ecuadorian children, compared with BCG alone. To determine how much longer protection might continue, the study was reblinded to permit 48 additional months of follow-up. During months 13–18, CL incidence remained lower in the vaccine group, compared with that in the control group (5.9% vs. 13.8%; χ2=8.8; P=.003), with vaccine efficacy calculated at 56.5% (95% confidence interval, 18.7%–76.7%); however, during months 24–60, no significant between-group differences were detected. Periodic administration of boosters may be necessary to maintain whole-parasite–vaccine protection against New World CL
RESUMEN Con el objetivo de determinar, mediante la solubilidad del silicio y aluminio en medio alcalino, la temperatura y el tiempo de activación térmica en que las tobas zeolitizadas del yacimiento ...Caimanes se comportan más reactivas, se caracterizó el material zeolítico natural y calcinado a través de Fluorescencia de Rayos X, Difracción de Rayos X y Microscopía Electrónica de Barrido. La solubilidad de aluminio y el silicio en medio alcalino de estas tobas zeolitizadas activadas térmicamente muestran que los materiales calcinados a 500ºC, son más reactivos para los dos elementos aluminio y silicio. Los mejores resultados se encuentran entre 60 y 90 minutos, con la mejor variante técnico-económica del tiempo de activación a 60 minutos. Los resultados permitieron determinar que en la reacción puzolánica de estos materiales predomina el efecto físico, además es posible obtener un material puzolánico que permite el reemplazo parcial del cemento Portland como aglomerante, para mantener o mejorar sus propiedades físico-mecánicas. Las fases minerales identificadas por DRX en la muestra de toba zeolitizada natural son la heulandita-clinoptilolita, calcita y cuarzo. Además, luego de la activación a 350ºC las fases permanecen sin cambios perceptibles por esta técnica, no así a 500ºC, donde las fases zeolíticas desaparecen, quedando solamente la calcita y el cuarzo.
The sparse representation of signals defined on Euclidean domains has been successfully applied in signal processing. Bringing the power of sparse representations to non-regular domains is still a ...challenge, but promising approaches have started emerging recently. In this paper, we investigate the problem of sparsely representing discrete surfaces and propose a new representation that is capable of providing tools for solving different geometry processing problems. The sparse discrete surface representation is obtained by combining innovative approaches into an integrated method. First, to deal with irregular mesh domains, we devised a new way to subdivide discrete meshes into a set of patches using a feature-aware seed sampling. Second, we achieve good surface approximation with over-fitting control by combining the power of a continuous global dictionary representation with a modified Orthogonal Marching Pursuit. The discrete surface approximation results produced were able to preserve the shape features while being robust to over-fitting. Our results show that the method is quite promising for applications like surface re-sampling and mesh compression.
The computation of geodesic distances is an important research topic in Geometry Processing and 3D Shape Analysis as it is a basic component of many methods used in these areas. In this work, we ...present a minimalistic parallel algorithm based on front propagation to compute approximate geodesic distances on meshes. Our method is practical and simple to implement and does not require any heavy pre-processing. The convergence of our algorithm depends on the number of discrete level sets around the source points from which distance information propagates. To appropriately implement our method on GPUs taking into account memory coalescence problems, we take advantage of a graph representation based on a breadth-first search traversal that works harmoniously with our parallel front propagation approach. We report experiments that show how our method scales with the size of the problem. We compare the mean error and processing time obtained by our method with such measures computed using other methods. Our method produces results in competitive times with almost the same accuracy, especially for large meshes. We also demonstrate its use for solving two classical geometry processing problems: the regular sampling problem and the Voronoi tessellation on meshes.
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