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本文介绍1.55μm波长可调谐DFB激光器的结构及特性。激光器腔长为250μm。隔离电阻约60Ω。在总电流恒定时,波长调谐范围超过15A（190GHz）。边模抑制比（SMSR）大于30dB。

采用金属有机化学汽相淀积工艺和脊型波导结构，实现了1．31μmAlGaInAs／InP应变多量子阱分布反馈激光器高功率输出。在25℃时，管芯最大输出功率超过50mW，阈值电流范围在13～20mA之间，发光面斜效率高于0．45mW／mA，边模抑制比超过35dB，室温中值寿命大于3×105小时。

【目的】本研究分析晚期乳腺癌患者血清HER-2／neu的水平与预后的关系，并探讨其临床意义。【方法】酶联免疫法（ELISA）检测94例晚期乳腺癌患者血清HER-2／neu的浓度．分析血清与组织中HER-2／neu表达的相关性，并分析其与患者预后的关系。【结果】94例晚期乳腺癌患者就诊时的血清HER-2／neu浓度为0．34-275．25μg／L（平均浓度为23．69μg／L）。血清HER-2／neu浓度的高低与化疗的有效性、疾病进展时间的长短无关。晚期乳腺癌患者的血清HER-2／neu浓度与肿瘤组织中HER-2／neu表达强阳性是一致的。【结论】血清HER-2／neu尚不能确立为独立的预后指标，需要更多的病例进行分析。

本文详细叙述了ＤＦＢ激光器的设计要点和新的工艺。采用一级全息光栅和二步液相外延法批量研制出高稳定单纵模工作的１．５５μｍ分布反馈激光器（ＤＦＢ—ＬＤ）。外延片成品率＞４０％。器件特性：２５℃时阈值电流２０ｍＡ，单面光功率＞１０ｍｗ，主边模抑制比ＳＭＳＲ达４３ｄＢ（λ／４相移光栅），谱线宽度△ν－２０ｄＢ＝０．３ｎｍ，调制速率＞１．８ＧＨｚ。可靠性测试显示：高温监测光谱稳定，２５°Ｃ时阈值退化率△Ｉｔｈ／ｔ＜０．３ｍＡ／ｋｈ，对应器件预估寿命将超过１０万ｈ。

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Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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By searching the literature on mental health of front-line medical workers in the prevention and control of novel coronavirus infection at home and abroad, the psychological stress response, influencing factors and intervention strategies of front-line medical workers were systematically summarized and analyzed. The front-line medical workers in epidemic prevention and control showed acute and chronic psychological stress reactions, including physical symptoms such as insomnia and fatigue, as well as psychological symptoms such as depression, anxiety, and post-traumatic stress. Risk and protective factors at three levels of individual, work and social affect psychological stress response. Online and offline psychological intervention can help relieve the pressure of front-line medical workers. At present, most of the research focuses on the outbreak period of the epidemic, and there is a lack of follow-up research on the long-term impact of the epidemic. Intervention studies report more on the development and implementation of the program, and less on the evidence-based test of the effect of the intervention. In the future, we can consider combining digital technology to develop intervention programs and test the effect of intervention. [ABSTRACT FROM AUTHOR]

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Meperfluthrin is one of the top-selling sanitary insecticide species in the domestic market, drawing widespread attention due to its environmental safety risk. In this paper, zebrafish was used as an experimental model to assess the cardiac developmental toxicity and oxidative damage caused by acute exposure to meperfluthrin in embryos and larvae. The acute toxicity assessment revealed that meperfluthrin is highly toxic to zebrafish embryos with a 72 h-LC50 of 0.756 μg/mL. After exposure to different doses of meperfluthrin (0, 0.2, 0.4, 0.8 μg/mL) for 72 h, the larvae from 0.4 and 0.8 μg/mL dose-treated groups showed deformities, including spine and tail curvature, pericardium and yolk sac edema, significant reduction of heart rate and hatchability, and incomplete embryonic development (shorter body length, smaller head, and eye area). Moreover, meperfluthrin of 0.2, 0.4, and 0.8 μg/mL induced atrial and ventricular differentiation in larvae, and down-regulated the expression of cardiac function-related genes myl7, myh6, and vmhc. It also increased the content of malondialdehyde (MDA), as well as decreased the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), resulting in the accumulation of reactive oxygen species (ROS) in the heart of larvae. The results of this paper indicate that meperfluthrin exposure has significant toxicity to the cardiac development of zebrafish embryos and is associated with oxidative damage. [ABSTRACT FROM AUTHOR]

Aiming at the problem of delays of multiple users arriving at the base station in the uplink sparse code multiple access (SCMA) macro-cell system, asynchronous detection algorithms were proposed with users grouped according to different delays and the same information between symbols was utilized and iterated, forming a message passing algorithm based on serial propagation ( SPMPA). Besides, aiming at the problem of worse bit error rate caused by partial marginalization algorithm used in MIMO-SCMA system, dynamic threshold partial marginalization algorithm (DTPM-MPA) was proposed. The simulation results show that the high bit error rate caused by symbol interference of asynchronous transmission is effectively reduced with SP-MPA and a flexible balance between computing complexity and bit error rate is formed with DTPM-MPA. [ABSTRACT FROM AUTHOR]

Portal vein thrombosis （PVT） is one of the common complications during the natural course of liver cirrhosis and has an important influence on the progression of liver cirrhosis. This article mainly summarizes the research advances in the risk factors for PVT. There are many risk factors for PVT， and Virchow’s triad， namely venous stasis， hypercoagulability， and vascular endothelial injury and systemic inflammation caused by surgery or trauma， are considered the main reasons for the development and progression of PVT. At present， more prospective studies are still needed to validate the predictive models for the risk of PVT that have certain application prospects in clinical practice. Cirrhotic patients with PVT tend to have a poor prognosis， and complete obstructive PVT is associated with increased mortality after liver transplantation. Recent studies have shown that prophylactic anticoagulant therapy is safe and effective in patients with liver cirrhosis and can thus help with the prevention and treatment of PVT. [ABSTRACT FROM AUTHOR]

SetRank is a novel Setwise Bayesian collaborative ranking model that can model implicit feedback data more closely to real-world scenarios. However, SetRank only considers collaborative information and lacks effective use of content information. In order to solve the above problems, a factorization machine model based on Setwise ranking, named SRFMs, is proposed. Drawing on the Setwise ranking proposed in SetRank to solve the problem of missing negative samples in implicit feedback, a factorization machine is chosen as a predictor to model content information, and model user preferences from the perspective of optimal item ranking. Furthermore, to improve the fixed feature representation and the lack of higher-order feature interactions in standard FM, inspired by IFM, SR-DIFM model is constructed to incorporate the SRFMs by combining input-aware networks with neural networks. Experimental results on two real-world datasets demonstrate that the proposed model outperforms the state-of-art model in terms of evaluation metrics including HR, NDCG and mAP, and can improve the accuracy of recommendations which make better use of user and item content information while solving the recommendation problem under implicit feedback. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Objective: To discuss the effect of microRNA-491-5p（miR-491-5p) over-expression on the proliferation and migration of the human nasopharyngeal carcinoma HONE-1 cells, and to provide the evidence for the study of the pathogenesis and targeted therapy of nasopharyngeal carcinoma. Methods: The human nasopharyngeal carcinoma HONE-1 cells were divided into control group (transfected with control plasmid) and miR-491-5p group (transfected with miR-491-5p plasmid). The transfection efficiencies of the HONE-1 cells in two groups were observed under fluorescence microscope; the proliferation activities of the HONE-1 cells in two groups were detected by CCK-8 assay; the number of migration HONE-1 cells in two groups were detected by Transwell chamber assay; the expression levels of Vimentin and E-cadherin mRNA in the HONE-1 cells in two groups were detected by real-time fluorescence quantitative PCR（RTqPCR) method; the expression levels of Vimentin and E-cadherin proteins in the HONE-1 cells in two groups were detected by Western blotting method. Results: Compared with control group, the proliferation activities（t=2. 832, P=0. 0473; t=4. 522, P=0. 0014; t=9. 308, P<0. 01) and number of migration HONE-1 cells (t=9. 639, P<0. 01) in miR-491-5p group at 24, 48, and 72 h after treatment were significantly decreased; compared with control group, the expression levels of Vimentin mRNA (t= 7. 535, P=0. 0017) and protein (t=7. 219, P=0. 0187) in the HONE-1 cells in miR-491-5p group were significantly decreased, and the expression levels of E-cadherin mRNA (t=4. 88, P=0. 0395) and protein (t=5. 754, P=0. 0289) were significantly increased. Conclusion: Over-expression of miR-491-5p can inhibit the proliferation, migration, and epithelial-mesenchymal transition (EMT) the human nasopharyngeal carcinoma cells. [ABSTRACT FROM AUTHOR]

Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Objective：To investigate the effects of up-regulation of protein phosphatase Mg2+/Mn2+- dependent 1F (PPM1F) on the proliferation and migration of nasopharyngeal carcinoma HONE-1 cells, and to clarify their mechanisms. Methods：The nasopharyngeal carcinoma HONE-1 cells were divided into pcDNA3. 1 group (transfected with pcDNA3. 1 plasmid) and pcDNA3. 1-Flag-PPM1F group (transfected with pcDNA3. 1-Flag-PPM1F plasmid). The expression levels of PPM1F and E-cadherin mRNA and proteins in the cells in two groups were detected by real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting methods； the activities of proliferation and clone formation rates of the cells in two groups were detected by CCK-8 method and clone formation assay; the scratch healing rates of the cells in two groups were detected by cell scratch assay, and the numbers of migation cells in two groups were detected by Transwell experiment. Results：Compared with pcDNA3. 1 group, the expression level of PPM1F mRNA in the cells in pcDNA3. 1-Flag-PPM1F group was significantly increased (P<0. 01), the expression amount of PPM1F protein was significantly increased, the expression levels of E-cadherin mRNA and protein in the cells were significantly increased (P<0. 01), the proliferation activity, the clone formation rate and the scratch healing rate were significantly decreased (P<0. 05 or P<0. 01), and the number of migration cells was significantly reduced (P<0. 05). Conclusion：Up-regulation of PPM1F expression can inhibit the proliferation and migration of nasopharyngeal carcinoma HONE-1 cells, and its mechanism may be related to intercellular adhesion. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Current sentiment classification algorithms lack the use of semantic association rules in feature extraction and produce a large number of words irrelevant to sentiment prediction after word segmentation, resulting in unrepresentative features mined. A convolution memory network emotion analysis model based on rough data inference was proposed. Firstly, according to the context information, rough data inference was used to obtain the Word2Vec word vector representation of the emotional word set of the text, and the FastText word vector was fused to improve the feature vector embedding layer. Secondly, convolutional neural network (CNN) was used to splice bi-directional long short-term memory (BiLSTM) to extract deeper emotional features. Finally, the attention mechanism was added to calculate the weight and screen the significant and important features. The experimental results on two data sets show that the emotional classification accuracy and F1 value of the model reach 84. 66% and 85. 1%, which are 2. 04% and 3. 1% higher than the highest value in the baseline model. [ABSTRACT FROM AUTHOR]

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Vitamin A is an essential nutrient for animals, which can maintain the normal growth and development of animals, maintain vision and other functions, and relieve the stress response of animals. It also plays an important role in regulating the reproduction, immunity, antioxidant and quality of animal products. A moderate amount of vitamin A can improve production efficiency, lack or excess will lead to unsatisfactory results, even cause disease, death. The article reviews the effect of vitamin A on growth and development, reproductive performance, antioxidant function, product quality and immune function of poultry, to provide reference for further application of vitamin A in poultry production. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)