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Nb3Al nanoparticles were directly synthesized by metallothermic reduction process in the molten salts with mNbCl5–nAlCl3 powders as raw materials and sodium as reducing reagent. The effects of different feeding material orders, soaking time, Nb content in raw materials, and 3NbCl5–AlCl3 content in molten salts on the obtained Nb3Al powder were discussed. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It is found that the only phase Nb3Al nanoparticles are obtained by controlling the variation of the feeding material orders, soaking time, and Nb content in raw materials. And the morphologies of as-prepared nanoparticles change owning to different 3NbCl5–AlCl3 contents in molten salts. [ABSTRACT FROM AUTHOR]

Abstract: Chalcopyrite-type CuInSe2 (CIS) nanoparticles were successfully synthesized by Se powder, CuCl, and InCl3 as raw materials and water as solvent at room temperature based on the principles of simultaneous equilibrium. The size of nanoparticles ranges from 20 to 50nm in diameter. The crystalline structure and morphology of the CIS nanoparticles were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy analysis (XPS), and transmission electron microscopy (TEM). The CIS nanoparticles were further enhanced after heat treatment at 500°C for 2h. The CIS film was fabricated by a mixture of CIS nanoparticles and novolac resin with a weight percentage of 30% by spin coating. The photoelectrical properties of such CIS films were measured and the results show an incident light density of 7.63mWcm−2 with the bias voltage of 0.4V, and the current density could approach 4.10mA/cm2 giving an on/off switching ratio of 2.0. [Copyright &y& Elsevier]

Neurodevelopmental disorders (NDDs) in children are a group of chronic developmental brain disorders caused by multiple genetic or acquired causes, including disorders of intellectual development, developmental speech or language disorders, autism spectrum disorders, developmental learning disorders, attention deficit hyperactivity disorder, tic disorders, and other neurodevelopmental disorders. With the improvement in the research level and the diagnosis and treatment techniques of NDDs, great progress has been made in the research on NDDs in children. This article reviews the research advances in NDDs, in order to further improve the breadth and depth of the understanding of NDDs in children among pediatricians.

We propose an adaptive and robust superpixel based hand gesture tracking system, in which hand gestures drawn in free air are recognized from their motion trajectories. First we employed the motion detection of superpixels and unsupervised image segmentation to detect the moving target hand using the first few frames of the input video sequence. Then the hand appearance model is constructed from its surrounding superpixels. By incorporating the failure recovery and template matching in the tracking process, the target hand is tracked by an adaptive superpixel based tracking algorithm, where the problem of hand deformation, view-dependent appearance invariance, fast motion, and background confusion can be well handled to extract the correct hand motion trajectory. Finally, the hand gesture is recognized by the extracted motion trajectory with a trained SVM classifier. Experimental results show that our proposed system can achieve better performance compared to the existing state-of-the-art methods with the recognition accuracy 99.17% for easy set and 98.57 for hard set.

Objective: To explore the effects of hypoxia on the proliferation of human leukemia HL-60 cells and the cellular expression of hypoxia inducible factor-1α (HIF-1α)., Methods: Human acute myeloid leukemia HL-60 cells with exponential growth in routine culture were exposed to 50, 200, 400, 800 µmol/L CoCl(2) to mimic hypoxic conditions. At 24, 48, and 72 h, the cells were collected for morphological observation, MTT assay, and real-time quantitative PCR for HIF-1α mRNA expression., Results: Compared with the cells without CoCl(2) treatment, the cells with CoCl(2) exposure exhibited obvious morphological changes and a significant growth inhibition which increased with CoCl(2)concentration and exposure time. At low concentrations (50-200 µmol/L), CoCl(2) treatment caused a dose- and time-dependent enhancement of HIF-1α expression in HL-60 cells., Conclusion: Hypoxia mimicked by CoCl(2) exposure significantly inhibits the proliferation of HL-60 cells, and at the non-toxic doses, CoCl(2) dose- and time-dependently increases the expression of HIF-1α. The mimicked hypoxic conditions do not cause differentiation of HL-60 cells.