Estimation of Spatiotemporal Gait Parameters in Walking on a Photoelectric System: Validation on Healthy Children by Standard Gait Analysis.

The use of stereophotogrammetry systems is challenging when targeting children's gait analysis due to the time required and the need to keep physical markers in place. For this reason, marker-less photoelectric systems appear to be a solution for accurate and fast gait analysis in youth. The aim of this study is to validate a photoelectric system and its configurations (LED filter setting) on healthy children, comparing the kinematic gait parameters with those obtained from a three-dimensional stereophotogrammetry system. Twenty-seven healthy children were enrolled. Three LED filter settings for the OptoGait were compared to the BTS P6000. The analysis included the non-parametric 80% limits of agreement and the intraclass correlation coefficient (ICC). Additionally, normalised limits of agreement and bias (NLoAs and Nbias) were compared to the clinical experience of physical therapists (i.e., assuming an error lower than 5% is acceptable). ICCs showed excellent consistency for most of the parameters and filter settings; NLoAs varied between 1.39% and 12.62%. An inverse association between the number of LEDs for filter setting and the bias values was also observed. Observations confirm the validity of the OptoGait system for the evaluation of spatiotemporal gait parameters in children.

Efficient catalytic degradation of methylene blue by a novel Fe3+-TiO2@CGS three-dimensional photoelectric system.

In this study, a novel three-dimensional photoelectric system was designed and constructed for the degradation of methylene blue (MB) via photocatalysis, electrocatalysis, and photoelectric catalysis. To this end, a Ti/RuO2-IrO2-SnO2-CeO2 electrode was prepared via a thermal oxidation coating method and used as a dimensionally-stable anode (DSA). The cathode was made of a titanium sheet with Fe3+-doped TiO2 loaded on coal gasification slag (CGS) (Fe3+-TiO2@CGS) as a photocatalyst. The factors affecting the degradation efficiency, such as the supporting electrolyte, current density, and initial pH were systematically investigated. The results revealed Fe3+-TiO2@CGS three-dimensional photoelectric system exhibiting efficient synergistic performance of photocatalysis and electrocatalysis with a synergistic factor of 1.11. Photo-generated holes (h+) were generated by light irradiation and direct anodic oxidation. Furthermore, hydroxyl radicals (HO·) radicals were induced via other pathways. Such active species showed highly-oxidizing abilities, beneficial to the degradation of methylene blue (MB). The representative Fe3+-TiO2@CGS three-dimensional photoelectric system showed super high degradation efficiency at pH 11 and current density of 18.76 mA cm-2. Using NaCl as a supporting electrolyte, the degradation yield reached 99.98% after 60 min of photoelectrical treatment. Overall, the novel Fe3+-TiO2@CGS three-dimensional photoelectrical system looks very promising for the highly efficient catalytic degradation of organic contaminants.

Application of a universal soil extractant for determining the available NPK: A case study of crop planting zones in central China.

Being important parameters of crop growth the precise measurements of available nitrogen (N), phosphorus (P) and potassium (K) on site not only help the farmer to control his budget but also helps to keep the environmental pollution under control. Currently, the existing extractant cannot be applied to rapidly determine the concentrations of available NPK by soil chemical analysis methods, simultaneously. In the present paper, a universal extraction reagent consisting of 0.45 M NaHCO3 and 0.374 M Na2SO4 buffered at pH 8.5 in association with a portable multi-channel photoelectric system has been proposed. The present method provides the most useful indication for the rapid determination of available NPK concentrations in neutral and calcareous soil in field. A large number of soil samples were collected from crop planting zones in Henan province of central China for evaluating the effectiveness of this universal extractant. A portable multi-channel photoelectric system associated with this universal soil extractant was exclusively designed to provide reliable and reproducible available NPK concentrations in soil extracts. The experimental results showed that available NPK concentrations determined by this method are highly correlated with the laboratory-based methods. A '3414' fertilizer scheme was applied to optimize the fertilizer recommendation for achieving the high targeted yield. The recommendation fertilizer system worked with a high correlation coefficient and fertilizer utilization rate has been established by this '3414' fertilizer scheme. With advantage of portability, accuracy and low cost, the proposed method can help to cut down the economic burden of the farmer and also it helps to optimize the utilization of the fertilizers by limiting its excessive usage and hence control the environmental pollution.