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After more than ten years of development, organic inorganic hybrid perovskite solar cells have become candidate devices with great industrialization prospects in the photovoltaic yield. However, the perovskite solar cells based hard substrate are heavy and not easy to carry, and the flexible perovskite so' cells can be well used in various portable wearable electronic products, with good development prospects. In this work, flexible TiO2 Nano rods were prepared on traditional hard substrates by electrospinning, and the effect of Lexie TiO2 Nano rods on the intrinsic properties of was studied. The surface roughness, morphology, structure and spectral performance of flexing TiO2 Nano rods on perovskite thin films were studied by using advanced defect evaluation microsystem, scanning electron microscope, X-ray diffractometer, ultravioletviribie spectrophotometer and fluorescence spectrometer, respectively. The results show that the perovskite thin films based on flexing TiO2 Nano rods have good spectral absorption and electron extraction cape- blitzes. This has certain guiding significance for the large-scale promotion and commercial application of flexible proves- kite photovoltaic devices. [ABSTRACT FROM AUTHOR]

In this paper, the total phenylethanosides (TPS) were extracted efficiently by an innovative extraction technology––deep eutectic solvent-based ultrasound-assisted extraction (DES-UAE) from Plantago asiatica L. Ten diverse types of DESs were synthesized as alternative extraction solutions. The extraction efficiency of DES-3 (constituted by choline chloride and lactic acid) was much higher than those of other DESs. On the basis of single factor tests and Box-Behnken design (BBD), the optimum processing parameters of DES-UAE as follow: DES-3 with molar ratio of 1:3, extraction temperature 51 °C, solid/liquid 22.5 mg/ml, water content 30%, ultrasonic power 65 W, extraction time 23 min. The extraction efficiency of TPS from Plantago asiatica L. was 8.395 mg/ml, which was more superior than those of organic solvents (water, methanol, 50% methanol, ethanol, 50% ethanol). The extraction kinetics experiment results showed that water content had a significant influence upon the extraction efficiency of TPS. At the same time, AB-8 macroporous resin column was used to efficiently isolate TPS from DES extraction with a recovery rate of 88.5%. [ABSTRACT FROM AUTHOR]

Missing and broken states of railway fasteners are directly related to driving safety. A deep network image detection method for railway fasteners based on residual network-single shot multibox detector (ResNet-SSD) is proposed to improve detection performance. Firstly, virtual image technology is used to simulate the defect states of fasteners, so as to expand feature information and overcome the imbalance problem of various fastener images. Secondly, ResNet is used to construct feature extraction network, and SSD is used for target detection to form ResNet-SSD network to detect the defect states of fasteners. Experimental results show that the ResNet-SSD has faster convergence speed and mean average precision (mAP) is increased by 3.06% from 95.47% to 98.53% after using the virtual image to expand the field collected fastener set; The detection accuracy of ResNet-SSD can reach 98.5% when the recall is 98.8%, which is higher than that of VGG16-SSD and the same as that of Faster-RCNN when intersection over union(IoU) is 0.5; The detection speed of this method is 6 times that of Faster RCNN and 1.5 times that of VGG16-SSD. Therefore, this method can meet the needs of real-time detection of railway fasteners. [ABSTRACT FROM AUTHOR]

The integrins and G protein-coupled receptors are both fundamental in cell biology. The cross talk between these two, however, is unclear. Here we show that β3 integrins negatively regulate G protein-coupled signaling by directly inhibiting the Gα13-p115RhoGEF interaction. Furthermore, whereas β3 deficiency or integrin antagonists inhibit integrin-dependent platelet aggregation and exocytosis (granule secretion), they enhance G protein-coupled RhoA activation and integrin-independent secretion. In contrast, a β3-derived Gα13-binding peptide or Gα13 knockout inhibits G protein-coupled RhoA activation and both integrin-independent and dependent platelet secretion without affecting primary platelet aggregation. In a mouse model of myocardial ischemia/reperfusion injury in vivo, the β3-derived Gα13-binding peptide inhibits platelet secretion of granule constituents, which exacerbates inflammation and ischemia/reperfusion injury. These data establish crucial integrin-G protein crosstalk, providing a rationale for therapeutic approaches that inhibit exocytosis in platelets and possibly other cells without adverse effects associated with loss of cell adhesion. Zhang et al. show that the adhesion receptor integrin β3 directly inhibits G protein mediated RhoA activation and granule secretion. A peptide mimicking this effect selectively inhibits platelet secretion but not integrin-mediated platelet adhesion. [ABSTRACT FROM AUTHOR]

The occurrence of laboratory safety accidents poses a great threat to the life and property safety of scientific researchers. Establishing a dual prevention mechanism from safety risk hierarchical control and hidden danger investigation and management can effectively curb the occurrence of accidents. This paper elaborates on the principle and significance of the dual prevention mechanism, combined with the actual situation of laboratory safety management in universities, and introduces the process of hazard identification and assessment, safety risk classification and hierarchical control, hidden danger investigation and management in the process of building the dual prevention mechanism, and discusses the key links such as the establishment and improvement of the responsibility system, priority of the risk control, implementation of hidden danger investigation and management, and continuous improvement. The construction experience is summarized and direction for further promotion is clarified. [ABSTRACT FROM AUTHOR]

Fluoride pollution is widely present in the living environment. As a critical period of brain development, the perinatal period is extremely vulnerable to fluoride. Studies have found that choline can protect the brain's memory and enhance the ability to focus. However, the effect of choline on perinatal fluoride‐induced nerve damage remains unclear. Therefore, 32 Kunming newly conceived female mice and their offspring mice were randomly divided into control, NaF, LC + NaF, and HC + NaF groups, and the HE staining, Y‐maze test, RT‐PCR, western blotting, immunohistochemistry, etc. were used in this study. The results showed that fluoride decreased the brain organ coefficients and brain protein content (p < 0.05, p < 0.01), and caused histomorphological damage in the hippocampus and cortex, which suggested that fluoride affected the development of the brain and damaged the brain. Moreover, the results of the Y‐maze test showed that fluoride increased the number of learning days, error reaction time, and total reaction time, and decreased the AchE activity in the brain (p < 0.05, p < 0.01), which indicated that fluoride reduced the learning and memory ability of the mice. Besides, the results showed that fluoride decreased the mRNA and protein expression levels of α4β2 nAChRs and α7 nAChRs in the hippocampus and cortex (p < 0.05, p < 0.01). However, perinatal choline supplementation reversed the aforementioned fluoride‐induced changes. In short, these results demonstrated that choline alleviated perinatal fluoride‐induced learning and memory impairment, which will provide a rationale for the mitigation and prevention of fluoride‐induced brain damage. [ABSTRACT FROM AUTHOR]