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Optoelectronics Letters 2024年第5期20卷 265-271页

作者： QI Hexin ZHOU Xuefang ZHANG Yinghui YANG Guowei BI Meihua hu miao School of Communication Engineering Hangzhou Dianzi UniversityHangzhou 310018China

A switchable and tunable multi-wavelength Brillouin erbium-doped fiber laser(MWBEFL) is designed and experimentally demonstrated. A Sagnac loop filter is employed as the switcher to obtain the double Brillouin frequency shift(BFS) of 0.172 nm(~20 GHz) and the quadruple BFS of 0.35 nm(~40 GHz). The working principles of the proposed laser are theoretically analyzed. The experimental results show that up to 8 Stokes lines with a wavelength interval of 0.172 nm can be obtained. When the Sagnac loop filter is used, two different output spectra with wavelength interval of 0.35 nm are obtained by adjusting the polarization controller(PC) and the optical signal-to-noise ratio(OSNR) is greater than 33 dB. By adjusting the Brillouin pump(BP) wavelength to investigate the tunability of the fiber laser, the output of 2—5 laser channels can be realized corresponding to 20 nm wavelength range. This approach is simple and can be employed for the microwave generation of other frequency ranges subject to the filtering shift of the Sagnac loop.

关键词： fiber laser filter

Upregulation of CDGSH iron sulfur domain 2 attenuates cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2023年第7期18卷 1512-1520页

作者： miao hu Jie huang Lei Chen Xiao-Rong Sun Zi-Meng Yao Xu-hui Tong Wen-Jing Jin Yu-Xin Zhang Shu-Ying Dong Department of Pharmacology School of PharmacyBengbu Medical CollegeBengbuAnhui ProvinceChina Key Laboratory of Cardiovascular and Cerebrovascular Diseases Bengbu Medical CollegeBengbuAnhui ProvinceChina Anhui Engineering Technology Research Center of Biochemical Pharmaceutical BengbuAnhui ProvinceChina

CDGSH iron sulfur domain 2 can inhibit ferroptosis,which has been associated with cerebral ischemia/reperfusion,in individuals with head and neck cancer.Therefore,CDGSH iron sulfur domain 2 may be implicated in cerebral ischemia/reperfusion injury.To validate this hypothesis in the present study,we established mouse models of occlusion of the middle cerebral artery and HT22 cell models of oxygen-glucose deprivation and reoxygenation to mimic cerebral ischemia/reperfusion injury in vivo and in vitro,respectively.We found remarkably decreased CDGSH iron sulfur domain 2 expression in the mouse brain tissue and HT22 cells.When we used adeno-associated virus and plasmid to up-regulate CDGSH iron sulfur domain 2 expression in the brain tissue and HT22 cell models separately,mouse neurological dysfunction was greatly improved;the cerebral infarct volume was reduced;the survival rate of HT22 cells was increased;HT22 cell injury was alleviated;the expression of ferroptosis-related glutathione peroxidase 4,cystine-glutamate antiporter,and glutathione was increased;the levels of malondialdehyde,iron ions,and the expression of transferrin receptor 1 were decreased;and the expression of nuclear-factor E2-related factor 2/heme oxygenase 1 was increased.Inhibition of CDGSH iron sulfur domain 2 upregulation via the nuclear-factor E2-related factor 2 inhibitor ML385 in oxygen-glucose deprived and reoxygenated HT22 cells blocked the neuroprotective effects of CDGSH iron sulfur domain 2 up-regulation and the activation of the nuclear-factor E2-related factor 2/heme oxygenase 1 pathway.Our data indicate that the up-regulation of CDGSH iron sulfur domain 2 can attenuate cerebral ischemia/reperfusion injury,thus providing theoretical support from the perspectives of cytology and experimental zoology for the use of this protein as a therapeutic target in patients with cerebral ischemia/reperfusion injury.

关键词： cerebral ischemia/reperfusion injury CDGSH iron sulfur domain 2 ferroptosis glutathione peroxidase 4 heme oxygenase 1 HT22 nuclear-factor E2-related factor 2 oxygen-glucose deprivation/reoxygenation injury stroke transferrin receptor 1

基于多波长分组的无源光网络故障监测系统设计及系统抗干扰性能分析

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光学学报 2024年第1期44卷 420-429页

作者：金哲怡毕美华滕旭阳胡淼杭州电子科技大学通信工程学院浙江杭州310018 上海交通大学区域光纤通信网与新型光通信系统国家重点实验室上海200240

提出了一种基于多波长分组的无源光网络系统监测方案,用于解决基于反射型的故障监测方案中用户之间易发生因干扰导致的链路状态误判的问题。该方案将不同波长分配到不同组,实现不同光网络单元(ONU)组之间的识别,从而避免不同组成员之间... 详细信息

提出了一种基于多波长分组的无源光网络系统监测方案,用于解决基于反射型的故障监测方案中用户之间易发生因干扰导致的链路状态误判的问题。该方案将不同波长分配到不同组,实现不同光网络单元(ONU)组之间的识别,从而避免不同组成员之间的干扰。在此基础上,将与光路终端距离相近的ONU分配到不同组内,以此降低组内ONU发生相互干扰的概率。此外,还研究了用户数量、传输脉冲功率和脉冲宽度对该系统性能的影响。通过理论推导与仿真可知,在检测波长通道数为4、检测光脉宽为10-8s、用户数量为16、最大距离差为2 km的无源光网络系统用户中,检测信号的信噪比为9.06 dB,识别精度为2 m。这些结果表明,基于多波长分组的无源光网络监测系统方案能够支持对大容量无源光网络系统的监控,并且在易发生干扰的用户数量较多的情况下具有较好的性能。

关键词：光通信光编码故障监测用户分布信噪比信号干扰比

基于维纳过程的低温环境下齿轮泵性能退化研究

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中国铁道科学 2024年第2期45卷 155-163页

作者：邱战国胡淼邢群雁宋宏智中国铁道科学研究院集团有限公司通信信号研究所北京100081 中国铁路电务技术中心北京100081

针对低温环境下(5℃以下)温度对齿轮泵性能退化的影响,以驼峰车辆减速器齿轮泵为研究对象,以流量为性能退化分析指标,建立齿轮泵流量计算模型;采用带有线性函数或指数函数漂移项的维纳过程模型,建立包含工作压力、温度和等效磨损间隙的... 详细信息

针对低温环境下(5℃以下)温度对齿轮泵性能退化的影响,以驼峰车辆减速器齿轮泵为研究对象,以流量为性能退化分析指标,建立齿轮泵流量计算模型;采用带有线性函数或指数函数漂移项的维纳过程模型,建立包含工作压力、温度和等效磨损间隙的多参数齿轮泵性能退化过程模型;通过齿轮泵流量计算模型的分析结果与现场试验数据对比,建模分析低温环境下齿轮泵性能退化过程中环境温度、工作压力对齿轮泵性能退化的影响。结果表明:低温环境下齿轮泵的性能退化与环境温度存在强相关性;线性漂移模型较指数漂移模型有更优的统计拟合效果;包含多参数带漂移的维纳过程模型能有效表征齿轮泵的性能退化过程。

关键词：齿轮泵驼峰车辆减速器维纳过程模型性能退化模型环境温度

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改进YOLOv7的自动驾驶目标检测算法

计算机工程与应用 2024年第11期60卷 165-172页

作者：胡淼姜麟陶友凤张志坚昆明理工大学理学院昆明650500

能否准确实时检测出道路上的车辆、行人等物体对自动驾驶车辆十分重要。针对自动驾驶场景下,车辆在行驶中存在的漏检,小目标检测效果差的问题,提出一种改进YOLOv7算法的自动驾驶目标检测算法。修改网络中扩充感受野的模块,减少感受野模... 详细信息

能否准确实时检测出道路上的车辆、行人等物体对自动驾驶车辆十分重要。针对自动驾驶场景下,车辆在行驶中存在的漏检,小目标检测效果差的问题,提出一种改进YOLOv7算法的自动驾驶目标检测算法。修改网络中扩充感受野的模块,减少感受野模块的大小,提高模型速度的同时增强对图片特征信息的提取能力。在主干网络输出端引入双层路由注意力机制,提高模型对小目标物体的检测性能。用EIOU损失函数替换算法原本的CIOU损失函数,将预测框与真实框的高度与宽度的差异最小化,加快模型收敛速度的同时达到更好的定位效果。实验结果表明:在KITTI数据集上,改进后的YOLOv7算法进行目标检测时,其mAP达到94.7%,在原YOLOv7算法上提升了3.1个百分点,并且在小目标物体检测上获得了更高的检测精度,有效提升了模型对小目标检测效果。

关键词：自动驾驶小目标检测 YOLOv7 注意力机制损失函数

遗传算法优化变分模态分解在轴承故障特征提取中的应用

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噪声与振动控制 2024年第1期44卷 148-153,204页

作者：单玉庭刘韬褚惟缪护昆明理工大学机电工程学院昆明650500 云南省科技厅云南省先进装备智能制造技术重点实验室昆明650500 昆明云内动力股份有限公司昆明650500

针对变分模态分解(Variational Mode Decomposition,VMD)过程中模态分量个数和惩罚参数大小依赖先验知识,单一或顺序优化单一参数可能导致局部最优的问题,提出以包络熵和包络峭度因子作为适应度函数,利用遗传算法全局寻优的特点,对VMD... 详细信息

针对变分模态分解(Variational Mode Decomposition,VMD)过程中模态分量个数和惩罚参数大小依赖先验知识,单一或顺序优化单一参数可能导致局部最优的问题,提出以包络熵和包络峭度因子作为适应度函数,利用遗传算法全局寻优的特点,对VMD的模态分量个数和惩罚参数组合进行优化。通过最优参数组合下的VMD对信号进行分解,可以获得多个本征模态分量(Intrinsic Mode Function,IMF),选择适应度函数最小IMF分量作为有效IMF分量进行包络解调,从中提取轴承信号的故障特征频率。对多种轴承故障类型信号进行分析并与其他方法对比,结果表明所提方法能有效提取轴承故障特征,有助于实现微弱故障条件下轴承故障特征频率的准确提取。

关键词：故障诊断变分模态分解包络熵包络峭度因子遗传算法包络解调

外科手术患者围术期使用质子泵抑制剂预防应激性溃疡的合理性分析

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中国社区医师 2024年第4期40卷 13-15页

作者：张娟胡淼南京医科大学第二附属医院江苏南京210011

目的:分析外科手术患者围术期使用质子泵抑制剂预防应激性溃疡的合理性。方法:回顾性分析2019年9月—2022年8月于南京医科大学第二附属医院外科行手术并于围术期应用质子泵抑制剂的1 640例患者的临床资料,统计各科室患者围术期质子泵抑... 详细信息

目的:分析外科手术患者围术期使用质子泵抑制剂预防应激性溃疡的合理性。方法:回顾性分析2019年9月—2022年8月于南京医科大学第二附属医院外科行手术并于围术期应用质子泵抑制剂的1 640例患者的临床资料,统计各科室患者围术期质子泵抑制剂预防应激性溃疡的不合理用药情况。结果:1 640例患者中,质子泵抑制剂预防应激性溃疡的不合理用药发生率为76.65%(1 257/1 640),用药指征不合理例数最多,占85.28%(1 027/1 257)。结论:该院外科手术患者围术期使用质子泵抑制剂预防应激性溃疡存在不合理情况,以用药指征不合理为主,相关部门需制定相关干预措施,规范外科围术期质子泵抑制剂的使用。

关键词：质子泵抑制剂围术期应激性溃疡合理性

用于碳烟燃烧的Ag(x)-Mn_(1)Co_(2.3)多孔纳米片催化剂的制备与性能研究

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现代化工 2024年第1期44卷 133-139页

作者：胡苗苗李苑君徐起翔李妍刘运权郑州大学生态与环境学院河南郑州450001 厦门大学能源学院福建厦门361102

采用等体积浸渍法制备了一系列Mn_(1)Co_(2.3)复合物负载不同质量分数Ag颗粒的催化剂,并用于碳烟颗粒的催化燃烧。结果表明,制得的Ag(10)-Mn_(1)Co_(2.3)在松散接触模式以及10%O_(2)/Ar+10%H_(2)O(g)+500μL/L NOx辅助气氛条件下表现出... 详细信息

采用等体积浸渍法制备了一系列Mn_(1)Co_(2.3)复合物负载不同质量分数Ag颗粒的催化剂,并用于碳烟颗粒的催化燃烧。结果表明,制得的Ag(10)-Mn_(1)Co_(2.3)在松散接触模式以及10%O_(2)/Ar+10%H_(2)O(g)+500μL/L NOx辅助气氛条件下表现出最佳的催化活性,其T_(10)､T_(50)和T_(90)分别为293､338℃和375℃。负载Ag不仅提高了催化剂的本征活性,而且Mn_(1)Co_(2.3)所具有的多孔纳米片形貌使该催化剂与反应物之间具有良好的固-固接触效率。

关键词：催化燃烧碳烟颗粒多孔纳米片 Ag负载

Petroleum heteroatom compounds in various commercial delayed coking liquids： characterized by FT-ICR MS and GC techniques

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Science China Chemistry 2017年第2期60卷 284-292页

作者： miao hu Chuang Guo Linzhou Zhang Suoqi Zhao Keng H. Chung Chunming Xu Quan Shi State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China Daqing Oilfield Limited Corporation Daqing 163159 China North huajin Chemical Industries Group Corporation Panjin 124000 China

Delayed coking is an important petroleum resid conversion process.The processability of coking liquids is known to be dependent on the heteroatom compounds present in the coking liquids.Eight commercial delayed coking liquids were characterized by electrospray ionization(ESI)Fourier transform ion cyclotron resonance mass spectrometry(ESI FT-ICR MS)and gas chromatographic techniques.High relatively abundant heteroatom compounds in the coking liquids were 1-4 aromatic-ring pyridinic nitrogen compounds,carbazoles,benzocarbazoles,phenols,mercaptans,benzothiophenes,dibenzothiophenes,and naphthobenzothiophenes.Coking liquids derived from various feeds had similar compound class types,molecular weight distribution ranges,and double bond equivalents(DBE).However,the concentration of individual compounds and the distribution of DBE versus carbon number of heteroatom compounds varied.A comparison of heteroatom compounds in coker feeds and products revealed the various reaction mechanism of heteroatom compounds occurred during the coking process.The results suggested that molecular-level process models can be developed for optimization of unit operation to obtain desirable products that meet the environmental specifications and quality requirements.

关键词：杂原子化合物气相色谱技术延迟焦化石油渣油液体傅里叶变换离子回旋共振质谱商业 MS

Blockade of neutrophil recruitment to tumor sites based on sialic acid-modified nanoplatforms enhances the efficacy of checkpoint blockade immunotherapy

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Asian Journal of Pharmaceutical Sciences 2023年第2期18卷 94-105页

作者： Meng Chen Zhaowei Qi Xianmin Meng Shuo Wang Xueying Zheng miao hu Xinrong Liu Yanzhi Song Yihui Deng School of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016China

Checkpoint inhibitors are designed to rejuvenate depleted or suppressed T cells in the tumor microenvironment,relying on the immune system to control and kill tumors.However,accumulating evidence indicates that tumor-infiltrating neutrophils impede the proliferation and activation of T cells and determine the resistance to checkpoint blockade and chemotherapy.In this study,sialic acid ligand-modified colchicine derivative phospholipid complexes specifically targeted tumor-associated neutrophils in the peripheral blood,blocked neutrophil accumulation in tumors,and attenuated the inhibitory effect of infiltrating neutrophils on T cells.Neutrophil blocking therapy enhanced the immunotherapy effect of the PD-L1 antibody in S180 advanced tumors and 4T1 breast cancer.Our study found that PD-L1 antibody monotherapy increased the tumor infiltration of immunosuppressive neutrophils.Combination therapy with neutrophil blocking can greatly reduce tumor-infiltrating neutrophils and increase the proliferation of cytotoxic CD8^(+) T lymphocytes in the tumor.The combination therapy significantly improved the survival rate of mice with advanced S180 tumors and increased the sensitivity of immune checkpoint inhibitors to 4T1 cold tumors.

关键词： Neutrophil blockade Combination immunotherapy Sialic acid