9 research outputs found

    Proximal humerus fractures in the pediatric population: a systematic review

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    PurposeProximal humerus fractures and epiphyseal separations in skeletally immature children and adolescents are traditionally treated non-operatively. Recently, authors have described the operative fixation of these injuries, particularly in older children and adolescents with displaced fractures. We performed a systematic review of the literature to identify operative indications for proximal humerus fractures in children and to compare the results by age, displacement, and treatment modality.MethodsA systematic review of the literature from January 1960 to April 2010 was performed. All studies with patients under the age of 18 years who were treated for a proximal humerus fracture either operatively or non-operatively were included.ResultsThe available literature is largely composed of uncontrolled case series (Level IV). According to findings, the literature shows that asymptomatic union is the rule in proximal humerus fractures in children and adolescents. Poorer outcomes were noted in operatively treated patients, patients with more displaced fractures, and older patients.ConclusionsThe currently available literature supports a non-operative treatment approach, particularly in younger children with more growth remaining. Older patients (>13 years) with more widely displaced fractures may benefit from anatomic reduction with stabilization, though the data in the literature at this point is too weak to strongly recommend this approach. Further analysis with a more rigorous scientific method is necessary to evaluate the optimum treatment modality in this subgroup

    Texture Coding in the Rat Whisker System: Slip-Stick Versus Differential Resonance

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    Rats discriminate surface textures using their whiskers (vibrissae), but how whiskers extract texture information, and how this information is encoded by the brain, are not known. In the resonance model, whisker motion across different textures excites mechanical resonance in distinct subsets of whiskers, due to variation across whiskers in resonance frequency, which varies with whisker length. Texture information is therefore encoded by the spatial pattern of activated whiskers. In the competing kinetic signature model, different textures excite resonance equally across whiskers, and instead, texture is encoded by characteristic, nonuniform temporal patterns of whisker motion. We tested these models by measuring whisker motion in awake, behaving rats whisking in air and onto sandpaper surfaces. Resonant motion was prominent during whisking in air, with fundamental frequencies ranging from approximately 35 Hz for the long Delta whisker to approximately 110 Hz for the shorter D3 whisker. Resonant vibrations also occurred while whisking against textures, but the amplitude of resonance within single whiskers was independent of texture, contradicting the resonance model. Rather, whiskers resonated transiently during discrete, high-velocity, and high-acceleration slip-stick events, which occurred prominently during whisking on surfaces. The rate and magnitude of slip-stick events varied systematically with texture. These results suggest that texture is encoded not by differential resonant motion across whiskers, but by the magnitude and temporal pattern of slip-stick motion. These findings predict a temporal code for texture in neural spike trains

    Effects of Iron Species on Low Temperature CO2 Electrolyzers

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    Electrochemical energy conversion devices are considered key in reducing CO2 emissions and significant efforts are being applied to accelerate device development. Unlike other technologies, low temperature electrolyzers have the ability to directly convert CO2 into a range of value‐added chemicals. To make them commercially viable, however, device efficiency and durability must be increased. Although their design is similar to more mature water electrolyzers and fuel cells, new cell concepts and components are needed. Due to the complexity of the system, singular component optimization is common. As a result, the component interplay is often overlooked. The influence of Fe‐species clearly shows that the cell must be considered holistically during optimization, to avoid future issues due to component interference or cross‐contamination. Fe‐impurities are ubiquitous, and their influence on single components is well‐researched. The activity of non‐noble anodes has been increased through the deliberate addition of iron. At the same time, however, Fe‐species accelerate cathode and membrane degradation. Here, we interpret literature on single components to gain an understanding of how Fe‐species influence low temperature CO2 electrolyzers holistically. The role of Fe‐species serves to highlight the need for considerations regarding component interplay in general

    Use of Lateral Access in the Treatment of the Revision Spine Patient

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    With the rate of spinal surgery increasing, we have seen a concomitant increase in the number of revision cases. It is, therefore, important to have a systematic approach to the management of these complicated patients with unique problems. A thorough understanding of the different pathologies affecting revision spine patients is critical to an effective treatment recommendation. Lateral access is a useful management approach since it can avoid the complications of operating through previous approaches. Furthermore, it possesses certain advantages for treatment in specific circumstances outlined in this paper. Long-term studies are needed to demonstrate the safety and efficacy of the lateral approach compared to the anterior and posterior approaches in the treatment of revision spine patients
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