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变质量力学系统Nielsen方程的形式不变性

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兵工学报 2005年第2期26卷 228-230页

作者：张军方建会陈培胜石油大学应用物理系山东东营257061

力学系统对称性与守恒量的研究在数学、力学、物理学中都具有非常重要的意义。力学系统的对称性与守恒量的近代理论主要有Noether对称性理论和Lie对称性理论。形式不变性是不同于Noether对称性和Lie对称性的一种新的对称性理论。本文研... 详细信息

力学系统对称性与守恒量的研究在数学、力学、物理学中都具有非常重要的意义。力学系统的对称性与守恒量的近代理论主要有Noether对称性理论和Lie对称性理论。形式不变性是不同于Noether对称性和Lie对称性的一种新的对称性理论。本文研究变质量力学系统Nielsen方程的形式不变性 ,给出变质量保守力学系统Nielsen方程的形式不变性的定义和判据 ,研究形式不变性和Noether对称性的关系。

关键词：力学系统形式不变性 Nielsen方程变质量 Noether对称性 Lie对称性守恒量理论代理研究形式

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连铸参数对高碳钢小方坯二次枝晶间距的影响

钢铁 2006年第9期41卷 37-39,43页

作者：冯军陈伟庆韩静段贵生北京科技大学冶金与生态工程学院北京100083

通过研究高碳钢小方坯连铸参数对铸坯二次枝晶臂间距的影响发现:采用结晶器电磁搅拌、加大二冷比水量,二次枝晶臂间距减小;过热度升高、拉速增大,二次枝晶臂间距增大。无M-EMS的铸坯接近中心的区域,仍然是枝晶臂发达的柱状晶组织;采用... 详细信息

通过研究高碳钢小方坯连铸参数对铸坯二次枝晶臂间距的影响发现:采用结晶器电磁搅拌、加大二冷比水量,二次枝晶臂间距减小;过热度升高、拉速增大,二次枝晶臂间距增大。无M-EMS的铸坯接近中心的区域,仍然是枝晶臂发达的柱状晶组织;采用结晶器电磁搅拌,促使铸坯中心区域形成粒状等轴晶组织;随搅拌电流增大,二次枝晶间距明显减小。随二次枝晶臂间距增大,渗透率增加,造成铸坯中心碳偏析加重。

关键词：高碳钢小方坯二次枝晶臂间距

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基于小波分析的电磁干扰测量技术研究

电子与信息学报 2010年第5期32卷 1229-1233页

作者：刘胜张兰勇张利军哈尔滨工程大学自动化学院哈尔滨150001

该文提出了一种新颖的可在开阔场快速测试受试设备的电磁干扰的数字信号处理技术。利用小波变换对测试信号分频滤波处理,可以在被环境噪声污染的地方进行受试设备的电磁辐射干扰测试。基于小波分析的阈值函数滤波方法得到应用。利用小... 详细信息

该文提出了一种新颖的可在开阔场快速测试受试设备的电磁干扰的数字信号处理技术。利用小波变换对测试信号分频滤波处理,可以在被环境噪声污染的地方进行受试设备的电磁辐射干扰测试。基于小波分析的阈值函数滤波方法得到应用。利用小波分析时频都可局部化的特点计算出环境噪声的相关性,提取出噪声的时频特性,并由给出的阈值函数对噪声滤除或者衰减,得到受试设备的实际电磁辐射信号。测试方法使得受试设备不必进入暗室即可进行电磁辐射干扰测量,既节省了测试费用又方便了受试设备的电磁干扰测试。系统运行结果证明此方法在30Hz～1000MHz的频段内成功衰减并滤除了环境噪声。

关键词：电磁干扰测量小波分析阈值函数滤波

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彩色多普勒检测肝硬化门静脉血流动力学变化

中国误诊学杂志 2008年第13期8卷 3061-3062页

作者：张馨月吕胜军吉林省肝胆病医院电诊科 130062

目的:通过测定肝硬化患者门静脉的血流动力学指标,探讨其与肝硬化门静脉高压症形成的关系。方法:采用彩色多普勒超声分别测量50例健康者(对照组)及151例肝硬化门静脉高压症患者(肝硬化组)门静脉系统血管内径、血流速度、血流量,并进行... 详细信息

目的:通过测定肝硬化患者门静脉的血流动力学指标,探讨其与肝硬化门静脉高压症形成的关系。方法:采用彩色多普勒超声分别测量50例健康者(对照组)及151例肝硬化门静脉高压症患者(肝硬化组)门静脉系统血管内径、血流速度、血流量,并进行对照分析。结果:肝硬化组门静脉及脾静脉内径、血流量均较对照组显著升高,而血流速度则较对照组下降显著,两组间比较(P<0.05)。结论:用彩色多普勒超声检测门静脉血流动力学有助于判定门静脉高压及随访观察,为临床治疗方案的选择提供依据。

关键词：肝硬化/超声检查高血压门静脉/超声检查血液动力学现象超声检查多普勒彩色

Correlation between circulating myeloid-derived suppressor cells and Th17 cells in esophageal cancer

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World Journal of Gastroenterology 2012年第38期18卷 5454-5461页

作者： Zhi-jun Jiao Jing-Jing Gao sheng-Hao Hua De-Yu Chen Wen-Hong Wang Hui Wang Xu-Hui Wang Hua-Xi Xu Key Laboratory of Medical Immunology Depament of Laboratory MedicineAffiliated Hospital of Jiangsu Uni-versityZhenjiang 212013Jiangsu ProvinceChina Institute of Oncology Affiliated Hospital of Ji-angsu UniversityZhenliang 212001Jiangsu ProvinceChina Department of Pathogenic Biolo-gy School of Medical Science and Laboratory MedicineJiangsuUniversityZhenjiang 212013Jiangsu ProvinceChina

AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloidderived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA). METHODS: A total of 31 patients newly diagnosed with ECA and 26 healthy subjects were included in the current study. The frequencies of MDSCs and Th17 cells in peripheral blood were determined by flow cytometry. The mRNA expression of cytokines, arginase 1 (Arg1) and inducible NO synthase (iNOS) in peripheral blood mononuclear cells (PBMCs) and plasma Arg1 were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: There was an increased prevalence of MDSCs in the peripheral blood from ECA patients (15.21% ± 2.25%) when compared with healthy control (HC) (1.10% ± 0.12%, P < 0.0001). The plasma levels of Arg1 in ECA patients were significantly higher than those in HC (28.28 ± 4.10 ng/mL vs 9.57 ± 1.51 ng/ mL, P=0.0003). iNOS mRNA levels in the peripheral blood of ECA patients also showed a threefold increase compared with HC (P=0.0162). The frequencies of Th17 cells (CD4 + IL-17A + ) were significantly elevated in ECA patients versus HC (3.50% ± 0.33% vs 1.82% ± 0.19%, P=0.0001). Increased mRNA expression of IL-17 and ROR-γt was also observed in ECA patients compared with HC (P=0.0041 and P=0.0004, respectively), while the mRNA expression of IL-6 and tumor necrosis factor-α (TNF-α) showed significant decreases (P=0.0049 and P < 0.0001, respectively). No obvious correlations were found between the frequencies of MDSCs and Th17 cells in the peripheral blood from ECA patients(r=-0.1725, P=0.3534). Arg1 mRNA levels were positively correlated with levels of IL-6 (r=0.6404, P=0.0031) and TNF-α (r=0.7646, P=0.0001). Similarly, iNOS mRNA levels were also positively correlated with levels of IL-6 (r=0.6782, P=0.0007) and TNF-α (r=0.7633, P < 0.0001). CONCLUSION: This study reveals the relationship between circulating MDSCs and Th17 cells, which

关键词： Myeloid-derived suppressor cells Th17 cells Esophageal cancer Arginase Ⅰ Peripheral blood mononuclear cells Inducible NO synthase

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极化SAR图像相干斑滤波性能评估

系统工程与电子技术 2008年第1期30卷 71-74页

作者：王晓军闫抒升孙洪空军雷达学院预警探测装备系湖北武汉430019 武汉大学电子信息学院湖北武汉430079

针对相干斑抑制能力强弱,对极化白化滤波(PWF)和功率图(Span)两种极化合成孔径雷达(SAR)图像相干斑滤波器进行了性能评估,应用等效视数指标,提出分别在高、中、低灰度均匀区域进行测试的方法,并在ESAR与PiSAR图像上进行了检验。结果表明... 详细信息

针对相干斑抑制能力强弱,对极化白化滤波(PWF)和功率图(Span)两种极化合成孔径雷达(SAR)图像相干斑滤波器进行了性能评估,应用等效视数指标,提出分别在高、中、低灰度均匀区域进行测试的方法,并在ESAR与PiSAR图像上进行了检验。结果表明,在占图像比例较大的中等灰度区域内,使用全局参数时,PWF滤波输出的结果优于Span图像的输出结果,但在占图像比例较小的低灰度区域,由于参数估计不够准确,PWF的滤波结果并不优于Span图像。

关键词：极化SAR图像相干斑滤波性能评估

Effection of Lead Poisoning and Newcastle Disease Vaccine on Development of Egg Yellow Feather Quail

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Animal Husbandry and Feed Science 2011年第2期3卷 29-33,48页

作者： PANG You-zhi ZHAO De-ming ZHAO Shu-juan YANG You-bing CHEN sheng CUI Yan-jun College of Animal Science and Technology Henan University of Science and Technology Luoyang 471003 China College of AnimalMedicine China Agricultural University Beijing 100094 China

[ Objective] To investigate the effects of Newcastle disease vaccination and lead exposure on growth and development of egg yellow feather quail. [ Method] Ninety 14-day-old quails were assigned randomly to 10 groups （ n = 9）, and they fed and drunk at liberty. A 2 ×5 factorial design was used. The quail immunized with ND vaccine and those non-immunized were exposed to lead at a dosage of 0, 50,500, 1 000 and 2 000 mg/L, respectively. [Result] The ND immunization reduced body weight significantly （ P 〈 0.01 ） and increased liver index and serum levels of hy- aluronic acid in quail within 1 -2 weeks post inoculation. The quail exposed to 2 000 mg/L lead acetate had significantly lower body weight than the control （ P 〈 0.01 ）. From 7 weeks old, the same inhibitory effect was observed in the quail＇exposed to lead at different dosages （ P 〈 0.01 ）. In addition, the lead poisoning could cause decreased feed intake, depilation, gonadal dysgenesis, and increased serum levels of hyaluronic acid. [ Conduslon] The inhibitory effect of ND vaccination on growth of quail occurs within 1 -2 weeks post inoculation; thus, the effects of immune stress should not be worried in quail production. The lead poisoning has significant effects on body weight and feed intake of quail, and lead dosage and duration affect the inhibitory effects of lead. Gonadal dysgenesis is an important indicator of lead poisoning in. quail. The serum levels of hyaluronic acid can be used to determine whether the quail have been immunized with ND vaccine or have contacted lead pollutants.

关键词： Quail Development Hyaluronic acid Lead poisoning Stress