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高压管汇材料疲劳性能测试及P-S-N模型曲线的拟合 被引量:1
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作者 黄艳娟 周思柱 李宁 《长江大学学报(自然科学版)》 2024年第3期55-61,共7页
高压管汇作为压裂设备中的主要易损件之一,其失效危害较大。它的失效原因主要是疲劳、冲蚀、腐蚀或者材料缺陷引起的刺漏和爆裂,其中尤以疲劳失效最不可预估。目前,对于高压管汇材料的疲劳性能研究不够深入,为解决高压管汇材料疲劳寿命... 高压管汇作为压裂设备中的主要易损件之一,其失效危害较大。它的失效原因主要是疲劳、冲蚀、腐蚀或者材料缺陷引起的刺漏和爆裂,其中尤以疲劳失效最不可预估。目前,对于高压管汇材料的疲劳性能研究不够深入,为解决高压管汇材料疲劳寿命的准确描述问题,以某国产高压管汇材料为例,进行了一系列疲劳试验,并基于试验数据,采用多种分布模型和不同S-N模型进行拟合分析,得出综合评价拟合能力最强的P-S-N模型。结果表明,该材料在中长疲劳寿命区,Weibull三参数模型在7级应力水平下综合评价能力最好;在存活率分别为50%、90%、99%、99.9%时,指数S-N模型的拟合系数均大于0.98,拟合能力最好。得出的P-S-N模型曲线可以为高压管汇的疲劳寿命以及安全设计提供依据。 展开更多
关键词 高压管汇材料 正态分布模型 Weibull分布模型 p-s-N模型 幂函数s-N模型 指数s-N模型
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高质量的“U-G-I-S-C”教师教育模式构建研究
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作者 郑爽 王茹 房琛 《石家庄学院学报》 CAS 2024年第4期133-137,共5页
“U-G-I-S-C”教师教育模式能满足教师教育一体化发展、大学和中小学共同利益实现与优势发挥最大化、实现中国式现代化和教育强国建设培养卓越中小学教师的需要。为进一步提高我国教师教育质量,可从以下几方面优化“U-G-I-S-C”教师教... “U-G-I-S-C”教师教育模式能满足教师教育一体化发展、大学和中小学共同利益实现与优势发挥最大化、实现中国式现代化和教育强国建设培养卓越中小学教师的需要。为进一步提高我国教师教育质量,可从以下几方面优化“U-G-I-S-C”教师教育模式运行策略:明晰合作理念和共同利益目标,合作关系从松散走向共生;建立平等协商和高效工作机制,合作效果从单兵作战走向互惠共赢;共同发展教育作为爱的事业,从利益联合走向文化融合;增进技术赋能,促进教师培养从断裂式走向全程浸入式并基于循证的教师教育过程;完善保障机制,汇聚各方组织的巨大合力。 展开更多
关键词 高质量 “U-g-I-s-C” 教师教育模式
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GRK5过表达对P301S Tau转基因小鼠抑郁样行为的影响及其机制
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作者 章天珍 沈洪涛 +2 位作者 龚正 赵斌 王岩 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2023年第3期573-579,共7页
目的:探讨G蛋白偶联受体激酶5(GRK5)过表达对P301S Tau转基因小鼠抑郁样行为的影响,并阐明其可能的作用机制。方法:17只雄性P301S Tau小鼠随机分为空白对照组(n=6,不做任何处理)、阴性对照组(n=5,双侧海马区给予空载对照病毒)和过表达组... 目的:探讨G蛋白偶联受体激酶5(GRK5)过表达对P301S Tau转基因小鼠抑郁样行为的影响,并阐明其可能的作用机制。方法:17只雄性P301S Tau小鼠随机分为空白对照组(n=6,不做任何处理)、阴性对照组(n=5,双侧海马区给予空载对照病毒)和过表达组(n=6,双侧海马区给予GRK5过表达病毒)。糖水偏好实验检测各组小鼠糖水偏好率,悬尾实验(TST)和强迫游泳实验(FST)检测各组小鼠不动时间百分率,Western blotting法检测各组小鼠海马组织中神经功能相关蛋白表达水平,免疫荧光染色检测各组小鼠海马组织中小胶质细胞标记物抗体(IBA1)、神经元特异性核蛋白(NeuN)和胶质纤维酸蛋白(GFAP)表达情况。结果:糖水偏好实验检测,与空白对照组和阴性对照组比较,过表达组小鼠糖水偏好率升高(P<0.05)。TST和FST检测,与空白对照组和阴性对照组比较,过表达组小鼠不动时间百分率升高(P<0.05)。Western blotting法检测,与空白对照组和阴性对照组比较,过表达组小鼠海马组织中GRK5、Tau T205和IBA1蛋白表达水平升高(P<0.05),突触小泡蛋白(SYN)蛋白表达水平降低(P<0.05)。免疫荧光染色检测,与空白对照组比较,阴性对照组和过表达组小鼠海马组织中均有增强绿色荧光蛋白(EGFP)表达,EGFP主要与NeuN发生共定位,小胶质细胞和星形胶质细胞中几乎未观察到EGFP;与空白对照组和阴性对照组比较,过表达组小鼠海马组织中小胶质细胞数增加(P<0.05)。结论:海马组织中GRK5过表达诱导P301S Tau小鼠抑郁样行为,其机制可能与GRK5在神经元核中表达水平升高有关。 展开更多
关键词 小鼠 p301s g蛋白偶联受体激酶5 抑郁样行为 TAU蛋白
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On the Cosmic Evolution of the Quantum Vacuum Using Two Variable G Models and Winterberg’s Thesis
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1134-1160,共27页
We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckion... We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckions. These material particles interact indirectly, and have very strong restoring forces keeping them a finite distance apart from each other within their respective species. Because of their mass compensating effect, the vacuum appears massless, charge-less, without pressure, net energy density or entropy. In addition, we consider two varying G models, where G, is Newton’s constant, and G<sup>-1</sup>, increases with an increase in cosmological time. We argue that there are at least two competing models for the quantum vacuum within such a framework. The first follows a strict extension of Winterberg’s model. This leads to nonsensible results, if G increases, going back in cosmological time, as the length scale inherent in such a model will not scale properly. The second model introduces a different length scale, which does scale properly, but keeps the mass of the Planck particle as, ± the Planck mass. Moreover we establish a connection between ordinary matter, dark matter, and dark energy, where all three mass densities within the Friedman equation must be interpreted as residual vacuum energies, which only surface, once aggregate matter has formed, at relatively low CMB temperatures. The symmetry of the vacuum will be shown to be broken, because of the different scaling laws, beginning with the formation of elementary particles. Much like waves on an ocean where positive and negative planckion mass densities effectively cancel each other out and form a zero vacuum energy density/zero vacuum pressure surface, these positive mass densities are very small perturbations (anomalies) about the mean. This greatly alleviates, i.e., minimizes the cosmological constant problem, a long standing problem associated with the vacuum. 展开更多
关键词 Winterberg model planck particles positive and Negative Mass planck particles planckions Quantum Vacuum space as a superfluid/supersolid Extended models for space Cosmological Constant Higgs Field as a Composite particle Higgs Boson Inherent Length scale for the Vacuum Dark Energy Cosmological scaling Behavior for the Quantum Vacuum Variable g models Extended gravity Newton’s Constant as an Order parameter High Energy Behavior for the Vacuum
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Ecological Security Assessment in County Area Based on P-S-R Model——A Case Study of Ningwu County,Shanxi Province 被引量:3
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作者 Feng Xufang Liu Jingmei Zhao Lijuan 《Meteorological and Environmental Research》 CAS 2014年第8期13-15,19,共4页
To further understand the status quo and change tendency of ecological security in county area, we took the example of Ningwu County, the headstream of Fenhe River, confronting serious eco-environment problem and cons... To further understand the status quo and change tendency of ecological security in county area, we took the example of Ningwu County, the headstream of Fenhe River, confronting serious eco-environment problem and considerable human impacts. Taking Ningwu as the study area and using variation coefficient method to determine the weights of the indices, we built ecological security pattern based on Pressure-State-Response (P-S-R) Model of Organization for Economic Cooperation and Development. The ecological security status was evaluated by calculating eco-security index (ESI) with socio-economic statistical data of Ningwu during 2001 -2010. The results showed that the situation of eco-security had been improved from heavy alarm to relative safety during 2001 -2010. It reflected that the ecological economic system in Ningwu County tended to be relaxed constantly after experienced a sharp conflict between ecological environment and economic growth. The ecological safety awareness was growing, however, by force of the objective requirements of population growth and economic development, the situation of ecological security was still unstable. 展开更多
关键词 Ecological security p-s-R model Es/ Ningwu County China
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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran 被引量:1
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作者 Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran 《Acta Geochimica》 EI CAS CSCD 2019年第1期131-144,共14页
The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-el... The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits. 展开更多
关键词 gEOCHEMICAL signature Concentration–area(C–A) fractal principal component analysis(pCA) student’s t-value Fuzzy mineral prospectivity modeling(MpM) prediction–area(p–A) pLOT
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Forecasting S&P 500 Stock Index Using Statistical Learning Models 被引量:2
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作者 Chongda Liu Jihua Wang +1 位作者 Di Xiao Qi Liang 《Open Journal of Statistics》 2016年第6期1067-1075,共9页
Forecasting the movement of stock market is a long-time attractive topic. This paper implements different statistical learning models to predict the movement of S&P 500 index. The S&P 500 index is influenced b... Forecasting the movement of stock market is a long-time attractive topic. This paper implements different statistical learning models to predict the movement of S&P 500 index. The S&P 500 index is influenced by other important financial indexes across the world such as commodity price and financial technical indicators. This paper systematically investigated four supervised learning models, including Logistic Regression, Gaussian Discriminant Analysis (GDA), Naive Bayes and Support Vector Machine (SVM) in the forecast of S&P 500 index. After several experiments of optimization in features and models, especially the SVM kernel selection and feature selection for different models, this paper concludes that a SVM model with a Radial Basis Function (RBF) kernel can achieve an accuracy rate of 62.51% for the future market trend of the S&P 500 index. 展开更多
关键词 statistical Learning models s&p 500 Index Feature selection sVM RBF Kernel
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GSTP1、XPG基因多态性与晚期非小细胞肺癌患者铂类药物化疗疗效及生存期的关系 被引量:10
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作者 吕红英 李启才 +3 位作者 卫红军 项金瑜 姚如永 梁军 《中国癌症杂志》 CAS CSCD 北大核心 2012年第8期609-617,共9页
背景与目的:本文旨在探讨谷胱甘肽S转移酶P1(glutathione S-transferase P1,GSTP1)基因A105G和人着色性干皮病G组(xeroderma pigmentatosum group G,XPG)基因C46T多态性与晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者对以... 背景与目的:本文旨在探讨谷胱甘肽S转移酶P1(glutathione S-transferase P1,GSTP1)基因A105G和人着色性干皮病G组(xeroderma pigmentatosum group G,XPG)基因C46T多态性与晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者对以铂类药物为主方案的化疗疗效及生存期的关系。方法:经病理学确诊的晚期NSCLC患者85例,化疗前取静脉血采用DNA测序法检测GSTP1 A105G和XPG C46T多态性,给予以铂类药物为主方案的化疗,2个周期后进行临床疗效评价(RECIST标准)并统计疾病进展时间(time to progression,TTP)和总生存时间(overall survival,OS),分析GSTP1 A105G和XPG C46T多态性与化疗疗效及生存期的关系。结果:85例晚期NSCLC患者中,GSTP1 A/G+G/G基因型和A/A基因型患者化疗有效率分别为43.59%和19.57%,差异有统计学意义(χ2=5.738,P<0.05);XPG C/C基因型和C/T+T/T基因型患者化疗有效率分别为42.86%和18.60%,差异有统计学意义(χ2=5.886,P<0.05);联合多态性分析显示,同时携带GSTP1 A/G+G/G和XPG C/C基因型患者化疗有效率最高为44.74%,组间比较差异有统计学意义(P<0.05)。至随访结束,81例患者中位TTP为6.5个月,其中GSTP1 A/G+G/G基因型为8.0个月,A/A基因型为6.0个月,差异有显著统计学意义(χ2=14.688,P<0.01);XPG C/C基因型为7.5个月,C/T+T/T基因型为6.0个月,差异有显著统计学意义(χ2=10.897,P<0.01);联合多态性分析显示,同时携带GSTP1 A/G+G/G和XPG C/C基因型患者的中位TTP最长为8.0个月,组间比较差异有显著统计学意义(P<0.01)。78例患者中位OS为9.0个月,其中GSTP1 A/G+G/G基因型为11.0个月,A/A基因型为9.0个月,差异有显著统计学意义(χ2=14.522,P<0.01);XPG C/C基因型为10.5个月,C/T+T/T基因型为9.0个月,差异有显著统计学意义(χ2=12.136,P<0.01);联合多态性分析显示,同时携带GSTP1 A/G+G/G和XPG C/C基因型患者的中位OS最长为11.0个月,组间比较差异有显著统计学意义(P<0.01)。结论:GSTP1 A105G和XPG C46T多态性可单独及联合用于预测晚期NSCLC患者对以铂类药物为主方案的化疗疗效及生存期,初步提示可以根据患者基因型来指导个体化治疗。 展开更多
关键词 非小细胞肺癌 基因多态性 谷胱甘肽s转移酶p1 人着色性干皮病g 铂类 生存期
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基于等效电路模型的Mesh结构P/G网布线优化方法 被引量:3
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作者 马琪 张永伟 叶福军 《微电子学与计算机》 CSCD 北大核心 2005年第1期170-173,共4页
本文在对供电用串联电阻链的等效电路模型进行详细论证的基础上,根据Mesh结构P/G网所具有的结构特点,将P/G网电阻网络加以等效变换,得到比原网络规模小得多的等效简化网络。然后用现有的布线优化方法来优化简化网络,速度可提高至少一个... 本文在对供电用串联电阻链的等效电路模型进行详细论证的基础上,根据Mesh结构P/G网所具有的结构特点,将P/G网电阻网络加以等效变换,得到比原网络规模小得多的等效简化网络。然后用现有的布线优化方法来优化简化网络,速度可提高至少一个数量级。 展开更多
关键词 Mesh结构p/g 布线优化 等效网络
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P15^(INK4B)高表达对人黑色素瘤细胞G1/S进程的阻滞及与MAPK信号相关性之初探 被引量:2
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作者 刘军 柳惠图 +1 位作者 谭信 高萍 《细胞生物学杂志》 CSCD 北大核心 2002年第4期232-236,共5页
利用TdR-N_2O同步法分别获得P15高表达的MLIK6和表达空载体的MLC2的M期细胞和G_1期细胞,~3H-TdR掺入结果显示,与对照组细胞MLC2相比,实验组细胞MLIK6从G_1期进入S期时间延长2h,并且掺入强度明显减弱,DNA合成被抑制。进一步观察了P15^(IN... 利用TdR-N_2O同步法分别获得P15高表达的MLIK6和表达空载体的MLC2的M期细胞和G_1期细胞,~3H-TdR掺入结果显示,与对照组细胞MLC2相比,实验组细胞MLIK6从G_1期进入S期时间延长2h,并且掺入强度明显减弱,DNA合成被抑制。进一步观察了P15^(INK4B)对G_1/S相关调控蛋白的影响,在M期细胞释放8h(晚G_1期细胞)后,与对照组MLC2细胞相比,实验组MLIK6细胞中CyclinD1,CyclinE,Cdk4,C-Myc蛋白水平均降低。相反,P27^(KIP1)的表达却上升。同时探讨了MAPK信号在P15^(INK4B)阻抑A375细胞G_1/S转换中的作用与相关性,结果显示晚G_1期的MLIK6细胞中ERK1,ERK2水平变化不大,而具有活性的P-ERK1和P-ERK2均表现出下降。上述实验表明,P15^(INK4B)可能通过作用于G_1期相关的周期调节蛋白和抑制ERK1和ERK2活性,阻滞G_1/S转换与抑制DNA合成。 展开更多
关键词 p15^INK4B 高表达 人黑色素瘤细胞 g1/s进程 阻滞 MApK信号相关性 细胞周期
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基于GPRS和组态王的远程无线通信系统设计 被引量:5
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作者 陶玉贵 陈万顺 王勇 《数字技术与应用》 2020年第7期31-33,共3页
为实现对设备资源远程集中控制和实时监测,本文提出基于GPRS和组态王的远程无线通信系统设计方案。PLC采集终端设备状态数据,通过GPRS网络将数据传输到监控主机,利用组态王软件构成可视化的监控界面,从而实现对终端设备实时监控。实践证... 为实现对设备资源远程集中控制和实时监测,本文提出基于GPRS和组态王的远程无线通信系统设计方案。PLC采集终端设备状态数据,通过GPRS网络将数据传输到监控主机,利用组态王软件构成可视化的监控界面,从而实现对终端设备实时监控。实践证明,该系统运行稳定、数据采集实时性强,具有较高的应用前景和市场价值。 展开更多
关键词 无线通信系统 g p R s 组态王 p L C
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基于PLC和MCGS的温室环境控制系统设计 被引量:7
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作者 何国荣 《信息技术》 2016年第9期59-61,65,共4页
温室可为植物提供适宜的生长条件,根据植物的生长需求设计的基于PLC和MCGS组态软件的温室控制系统,使用空气温湿度传感器、土壤温湿度传感器、光照度传感器监测温室环境参数,通过控制风扇、喷灌设备、补光灯、保温灯等设备达到控制温室... 温室可为植物提供适宜的生长条件,根据植物的生长需求设计的基于PLC和MCGS组态软件的温室控制系统,使用空气温湿度传感器、土壤温湿度传感器、光照度传感器监测温室环境参数,通过控制风扇、喷灌设备、补光灯、保温灯等设备达到控制温室温湿度、光照度的目的。系统可进行自动/手动控制的切换,使用方便,经过测试,系统运行稳定可靠。 展开更多
关键词 温室环境控制 pLC MCgs
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在鼻咽癌细胞中EB病毒LMP1调控G1/S检测点重要相关蛋白的转录
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作者 宋鑫 李彩霞 +3 位作者 李永强 张建华 刘志敏 隋军 《昆明医学院学报》 2007年第6期43-48,共6页
目的在Tet-on-LMP1 HNE2鼻咽癌细胞中探讨EB病毒编码的潜伏膜蛋白1(LMP1)调控p16和cyclin D1的转录.方法采用Western blot方法、荧光素酶报道系统和RT-PCR方法检测在DOX诱导下不同时间点p16和cyclin D1的启动子活性和转录.结果LMP1可下... 目的在Tet-on-LMP1 HNE2鼻咽癌细胞中探讨EB病毒编码的潜伏膜蛋白1(LMP1)调控p16和cyclin D1的转录.方法采用Western blot方法、荧光素酶报道系统和RT-PCR方法检测在DOX诱导下不同时间点p16和cyclin D1的启动子活性和转录.结果LMP1可下调p16启动子活性和mRNA表达;同时上调cyclin D1启动子活性和mRNA表达.结论在Tet-on-HNE2鼻咽癌细胞中EB病毒LMP1在转录水平调控G1/S检测点重要相关蛋白p16和cyclin D1的表达. 展开更多
关键词 潜伏膜蛋白1 p16 CYCLIN D1 g1/s 检测点
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卡明斯视觉诗“r-p-o-p-h-e-s-s-a-g-r”视觉模态隐喻的概念元功能解读
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作者 李娅红 《南昌教育学院学报》 2012年第11期28-29,共2页
印刷体式与语言一样都属于社会符号资源,它同样具有语言的系统性和功能性。社会符号学意义上的隐喻包含了以副语言形式为表达方式的隐喻。由印刷体式表征的视觉模态隐喻在卡明斯视觉诗中通过陈述视觉模态与客体之间在世界中的体现关系... 印刷体式与语言一样都属于社会符号资源,它同样具有语言的系统性和功能性。社会符号学意义上的隐喻包含了以副语言形式为表达方式的隐喻。由印刷体式表征的视觉模态隐喻在卡明斯视觉诗中通过陈述视觉模态与客体之间在世界中的体现关系而体现了其语言的交流功能,它在与语言的转喻和隐喻关系层面实现了概念功能。 展开更多
关键词 卡明斯诗歌 “r-p-o-p-h-e-s-s-a-g-r” 视觉模态隐喻 概念元功能
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2019年长宁M_(s)6.0地震周边区域速度与P波各向异性成像研究
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作者 杨唯佳 周艳杰 +4 位作者 姜恩元 石玉涛 马啸 贺茜君 黄雪源 《地震》 CSCD 北大核心 2023年第4期1-20,共20页
利用基于程函方程求解的地震走时层析成像方法对2019年长宁M_(s)6.0地震震中及其周边区域进行反演成像,获得了该区域高分辨率三维P波、S波速度结构以及P波方位角各向异性参数分布,并对几个典型剖面的泊松比结构进行了分析。结果表明,方... 利用基于程函方程求解的地震走时层析成像方法对2019年长宁M_(s)6.0地震震中及其周边区域进行反演成像,获得了该区域高分辨率三维P波、S波速度结构以及P波方位角各向异性参数分布,并对几个典型剖面的泊松比结构进行了分析。结果表明,方位角各向异性对地震波P波走时具有显著的影响;研究区域上地壳速度结构存在显著的非均匀性,且一些相对低速异常与注水采盐、天然气水力压裂开采及废水回注等工业活动区域具有明显的对应关系,显示人类的工业活动可能已经对上地壳的物质性质产生了影响。长宁地震的发生可能由注水采盐活动直接诱发,而由工业活动所造成的速度异常结构对区域内地震的发生可能产生的影响是持续性的。区域内P波方位角各向异性可能受板块运动和主压应力影响,而长宁地震序列震源区域浅层P波方位角各向异性以近EW向为主,与该区域的主压应力方向基本一致。这些结果为认识四川盆地东南缘精细地壳结构、深部物质运动和动力学机制提供了新的资料。 展开更多
关键词 2019年长宁M_(s)6.0地震 层析成像 三维速度结构 p波方位角各向异性
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Crustal structure and accurate hypocenter determination along the Longmenshan fault zone 被引量:9
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作者 赵珠 范军 +2 位作者 郑斯华 长谷川昭 内茂木 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第6期66-73,共8页
A P and S wave velocity model is obtained for the crust in the region along the Longmenshan fault zone, Sichuan Province, China, by using data from a refraction profiling survey carried out in this region and those fr... A P and S wave velocity model is obtained for the crust in the region along the Longmenshan fault zone, Sichuan Province, China, by using data from a refraction profiling survey carried out in this region and those from local earthquakes. 202 local earthquakes along the fault zone are based on this velocity model, location errors being estimated to be about 1.5 km. The present relocations fairly improved the accuracy of hypocenter locations for earthquakes in this area, which is recognized from small scatter of data in the arrival time distance diagram compared with that for the original locations in the Earthquake Catalogue of Sichuan Seismic Network. The obtained hypocenter distribution shows that shallow earthquakes, confined to the upper crust in the depth range from 3 km to 22 km, are actively occurring along the main fault of the Longmenshan fault zone. The velocity model and the location method are presently used quite effective for precisely locating local earthquakes such as those in Sichuan Province. Installation of these with the real time processing system developed by Tohoku University in the Sichuan Telemetered Seismic Network would help to improve the location accuracy of events beneath the network. 展开更多
关键词 Longmenshan fault zone p wave s wave hypocenter determination velocity model arrive time curve
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Molecular signal transduction in vascular cell apoptosis 被引量:20
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作者 GENG YONG JIAN Center for Cardiovascular Biology and Atherosclerosis Research, Division of Cardiology, Department of Internal Medicine, University of Texas Houston Health Science Center Medical School, 6431 Fannin Street, MSB 6.045, Houston, TX 77030, USA 《Cell Research》 SCIE CAS CSCD 2001年第4期253-264,共12页
Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pa... Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., may influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and its major complication, the acute vascular syndromes. 展开更多
关键词 Apoptosis signal Transduction ARTERIOsCLEROsIs Comparative study Endothelium Vascular Humans models Biological Muscle smooth Vascular Research support U.s. gov't p.H.s.
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Transplantation of human hepatocytes into tolerized genetically immunocompetent rats 被引量:23
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作者 EdwinC.Ouyang CatherineH.Wu +2 位作者 CherieWalton KittichaiPromrat GeorgeY.Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期324-330,共7页
AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human... AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human hepatocytes was established by injection of primary human hepatocytes or Huh7 human hepatoma cells into the peritoneal cavities of fetal rats. Corresponding cells were subsequently transplanted into newborn rats via intrasplenic injection within 24h after birth. RESULTS: Mixed lymphocyte assays showed that spleen cells from non-tolerized rats were stimulated to proliferate when exposed to human hepatocytes, while cells from tolerized rats were not. Injections made between 15 d and 17 d of gestation produced optimal tolerization. Transplanted human hepatocytes in rat livers were visualized by immunohistochemical staining of human albumin. By dot blotting of genomic DNA in livers of tolerized rats 16 weeks after hepatocyte transplantation, it was found that approximately 2.5 X 10(5) human hepatocytes survived per rat liver. Human albumin mRNA was detected in rat livers by RT-PCR for 15 wk, and human albumin protein was also detectable in rat serum. CONCLUSION: Tolerization of an immuno-competent rat can permit transplantation, and survival of functional human hepatocytes. 展开更多
关键词 ALBUMINs Animals Cell Line Transformed Disease models Animal Female gene Expression graft survival Hepatitis HEpATOBLAsTOMA Hepatocytes Humans Immune Tolerance IMMUNOCOMpETENCE Liver Liver Neoplasms Lymphocyte Culture Test Mixed Microscopy Confocal pregnancy RNA Messenger RATs Rats sprague-Dawley Research support Non-U.s. gov't Research support U.s. gov't p.H.s.
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Promoting photocarriers separation in S-scheme system with Ni_(2)P electron bridge:The case study of BiOBr/Ni_(2)P/g-C_(3)N_(4) 被引量:4
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作者 Nannan Chen Xuemei Jia +5 位作者 Heng He Haili Lin Minna Guo Jing Cao Jinfeng Zhang Shifu Chen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期276-287,共12页
Constructing step-scheme(S-scheme)heterojunctions can considerably facilitate separation and transfer of photocarriers,as well as promote strong redox ability.The interface resistance of heterojunctions immediately af... Constructing step-scheme(S-scheme)heterojunctions can considerably facilitate separation and transfer of photocarriers,as well as promote strong redox ability.The interface resistance of heterojunctions immediately affects photocarrier separation and determines the photocatalytic activity.Herein,we constructed a novel Bi OBr/Ni_(2)P/g-C_(3)N_(4) heterojunction using Ni_(2)P as a novel electron bridge to reduce the interfacial resistance of photocarriers between Bi OBr and g-C3N4.The as-prepared 10% BiOBr/Ni2P/g-C_(3)N_(4) sample exhibited outstanding visible-light photocatalytic performance for methyl orange and rhodamine B removal,with degradation efficiencies of 91.4% and 98.9%,respectively.The excellent photocatalytic activity of Bi OBr/Ni_(2)P/g-C_(3)N_(4) was mainly attributed to the synergistic effects of the Ni2P cocatalyst and S-scheme heterojunction,which not only reduced the interface resistance but also retained the strong redox potential of the photocarriers.In addition,the formation of the S-scheme system was supported by active oxygen species investigation,current-voltage curves,and density functional theory calculations.This work provides a guideline for the design of highly efficient S-scheme photocatalysts with transition metal phosphates as electron bridges to improve photocarriers separation. 展开更多
关键词 BiOBr/Ni_(2)p/g-C_(3)N_(4) s-scheme Interfacial electron transfer Electron-bridge photocatalysis
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基于“G-U-S”模式的少先队辅导员专业发展机制探究
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作者 王轲祺 多强 《吉林省教育学院学报》 2023年第1期23-28,共6页
“G-U-S”模式是在“U-G-S”模式的基础上开创的以地方教育行政部门为主导、地方师范大学和中小学积极参与的少先队辅导员专业发展模式。此模式的实施需要发挥地方教育行政部门的行政与管理优势,并进行合理的第三方督导;发挥地方师范大... “G-U-S”模式是在“U-G-S”模式的基础上开创的以地方教育行政部门为主导、地方师范大学和中小学积极参与的少先队辅导员专业发展模式。此模式的实施需要发挥地方教育行政部门的行政与管理优势,并进行合理的第三方督导;发挥地方师范大学的理论与教育研究优势,提供智力支持和师资保障;利用中小学的实践基地和反馈优势,提供实践反思和反馈;强化少先队辅导员专业发展自主意识,使其树立终身学习理念。 展开更多
关键词 g-U-s”模式 少先队辅导员 专业发展
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