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Biometrics recognition takes advantage of feature extraction and pattern recognition to analyze the physical and behavioral characteristics of biological individuals to achieve the purpose of individual identification. As a typical biometric technology, palm print and palm vein have the characteristics of high recognition rate, stable features, easy location and good image quality, which have attracted the attention of researchers. This paper designs and develops a multispectral palm print and palm vein acquisition platform, which can quickly acquire palm spectrum and palm vein multispectral images with seven different wavelengths. We propose a multispectral palm print palmar vein recognition framework, and feature-level image fusion is performed after extracting features of palm print palmar vein images at different wavelengths. Through the multispectral palm print palm vein image fusion experiment, a more feasible multispectral palm print and palm vein image fusion scheme is proposed. Based on the results of image fusion, we further propose an improved convolutional neural network (CNN) for model training to achieve identity recognition based on multispectral palm print palm vein images. Finally, the effects of different CNN network structures and learning rates on the recognition results were analyzed and compared experimentally.

Automobile exhaust catalyst has been more and more widely used for creating a green life. It contains abundant platinum, palladium, rhodium, and rare earth cerium, compared with primary resources. It’s necessary to efficiently recover valuable metals with great application value. The feasibility of leaching cerium from hydrochloric acid system is mainly analyzed from the perspective of thermodynamics in this paper. The leaching experiment of hydrochloric acid oxidation is carried out. The results show that the leaching rate of cerium reaches only 46% when the concentration of hydrochloric acid was 4 mol/L, the reaction temperature was 80 °C, the amount of hydrogen peroxide was 10 ml, the liquid–solid ratio was 10:1, the reaction time was 2 h, and the stirring speed was 450 r/min. According to the metal equilibrium, it is inferred that the formation of stable Ce–Zr solid solution makes the lower leaching rate of cerium.

Urine strips are widely applied for rapid analysis of various indexes of urine for clinical examinations. The tests mainly rely on the application of a urine analyzer, which suffers several drawbacks and cannot meet the requirements of point-of-care testing (POCT). The integration of a smartphone with a biosensor has recently attracted great attention. We herein propose a human vision-based smartphone algorithm for colorimetric analysis of various urine indexes. A CIEDE2000 formula in CIELab color space is applied for the evaluation of color difference, which may greatly improve the analytical performances of urine strips. The proposed algorithm also possesses merits such as good accuracy, quantitative analysis, and limited calculation task, which is suitable for the application with smartphone platform. Experimental results demonstrate that the proposed method shows excellent reliability compared with the urine analyzer and some other algorithms. In addition, human real samples are successfully analyzed with excellent accuracy. Therefore, this work provides a convenient colorimetric tool for POCT urine analysis.

Spontaneous intracerebral hemorrhage (ICH) is a common and fatal subtype of stroke, with hypertension the most common cause of this disorder. Bone marrow derived mesenchymal stem cells (BM-MSCs) have been shown to elicit protective properties in stroke models. In the present study, male spontaneously hypertensive rats (SHR) were subjected to ICH by intracerebral injection with autologous blood, Wistar-Kyoto (WKY) rats were employed as control. The neurological function outcomes and blood-brain barrier (BBB) were assessed after BM-MSCs transplantation. Our results showed that BM-MSCs grafts via the tail vein significantly decreased the modified neurological severity score (mNSS) and the modified limb placing test (MLPT) score at 14 days after ICH, and the scores were gradually lowered till the end of test. Furthermore, BM-MSCs transplantation effectively attenuated the BBB permeability compared with the vehicle only group, as evidenced by the low level of Evans blue leakage in the BM-MSC group. In addition, we found that BM-MSCs grafts elevated the levels of tight junction associated protein occludin, and type IV collagen. Taken together, our results suggest that intravenously transplanted BM-MSCs exert therapeutic effects on ICH in spontaneously hypertensive rats. The underlying mechanisms are associated with the enhanced neurological function recovery and increased integrity of BBB. Our results provide the increased understanding of the underlying mechanisms and perspective of BMSCs in treatment for stroke.