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压力对PCBN复合材料烧结性质的影响及烧结机理研究

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高压物理学报 2016年第5期30卷 363-368页

作者：李勇徐会文张杰金慧邓韬贾晓鹏铜仁学院物理与电子工程学院贵州铜仁554300 太原重工轨道交通设备有限公司山西太原030001 吉林大学超硬材料国家重点实验室吉林长春130012

在高温高压条件下,通过硬质合金基体的高压原位熔渗法,研究了合成压力对聚晶立方氮化硼(PCBN)复合材料致密度、颗粒形貌及耐磨性的影响。测试结果显示:随着合成压力的提高,PCBN复合材料的致密度和耐磨性均有一定程度的提升。利用扫描电... 详细信息

在高温高压条件下,通过硬质合金基体的高压原位熔渗法,研究了合成压力对聚晶立方氮化硼(PCBN)复合材料致密度、颗粒形貌及耐磨性的影响。测试结果显示:随着合成压力的提高,PCBN复合材料的致密度和耐磨性均有一定程度的提升。利用扫描电子显微镜和能谱仪对碳化钨合金基体与立方氮化硼的结合界面进行了测试分析。测试结果表明:在高温高压条件下,立方氮化硼聚晶层与碳化钨硬质合金层中的元素彼此扩散、渗透,形成金属过渡层,将二者牢固地结合在一起。

关键词：高压聚晶立方氮化硼烧结机理致密度

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钢闸门结构时变刚度模型及其可靠度评估

上海交通大学学报 2003年第7期37卷 1114-1118页

作者：李典庆唐文勇张圣坤上海交通大学船舶与海洋工程学院上海200030

基于可靠性原理 ,建立了水工钢闸门结构正常使用极限状态刚度可靠度分析的极限状态方程 ,提出了钢闸门结构刚度可靠度分析的 3种计算模式 .对影响钢闸门结构构件刚度衰减的主要因素——钢材锈蚀进行了统计分析 ,得到了锈蚀规律 ,并进一... 详细信息

基于可靠性原理 ,建立了水工钢闸门结构正常使用极限状态刚度可靠度分析的极限状态方程 ,提出了钢闸门结构刚度可靠度分析的 3种计算模式 .对影响钢闸门结构构件刚度衰减的主要因素——钢材锈蚀进行了统计分析 ,得到了锈蚀规律 ,并进一步分析得到了闸门构件刚度的衰减模型 .以受弯构件为例 ,采用 JC法对其刚度可靠指标进行了计算分析 .结果表明 ,其刚度可靠指标满足结构可靠性总原则的要求 ,且露顶门的刚度可靠指标大于潜孔门的刚度可靠指标。

关键词：水工钢闸门刚度模型时变可靠度钢材锈蚀

Loss-of-function mutations of microRNA-142-3p promote ASH1L expression to induce immune evasion and hepatocellular carcinoma progression

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World Journal of Gastroenterology 2025年第1期31卷 126-145页

作者： Xing-Hui Yu Yan Xie Jian Yu Kun-Ning zhang Zhou-Bo Guo Di Wang Zhao-Xian Li Wei-Qi zhang Yu-Ying Tan Li zhang wen-Tao Jiang School of Medicine Nankai UniversityTianjin 300192China Tianjin Key Laboratory of Molecular Diagnosis and Treatment of Liver Cancer Tianjin First Center HospitalTianjin 300192China Department of Liver Transplantation Tianjin First Center HospitalTianjin 300192China First Central Clinical School Tianjin Medical UniversityTianjin 300192China

BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated *** therapeutic targets are beneficial to treat and predict the ***,the exact molecular mechanisms leading to the progression of HCC are still *** has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor *** this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between *** To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC *** In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC ***,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,*** statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank *** In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival ***1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated ***,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via *** the exploration mechanism,we found ASH1L may promote an immunosuppressive mi

关键词： Hepatocellular carcinoma MicroRNA-142-3p ASH1L Immune evasion Tumor immune microenvironment Apoptosis

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拟Bent函数的性质和构造

数学学报（中文版） 2004年第6期47卷 1175-1184页

作者：张习勇韩文报郑州信息工程大学信息工程学院郑州450002

本文将基本2-群中拟Bent函数的概念推广到一般的有限Abel群中,统一了目前几乎所有的Bent函数概念,完全刻画了一类拟Bent函数和Bent函数的本质联系,给出了几种拟Bent函数的构造方法,拟Bent函数和相对差集的一种关系以及一种用拟Bent函数... 详细信息

本文将基本2-群中拟Bent函数的概念推广到一般的有限Abel群中,统一了目前几乎所有的Bent函数概念,完全刻画了一类拟Bent函数和Bent函数的本质联系,给出了几种拟Bent函数的构造方法,拟Bent函数和相对差集的一种关系以及一种用拟Bent函数构造Bent函数的方法.最后,利用Galois环和组合集,找到一类拟Bent函数.

关键词： Bent函数拟Bent函数 Galois环

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基于传力路径的减震设计方法研究

工程抗震与加固改造 2017年第1期39卷 64-70页

作者：杜永峰张文丽黄小宁兰州理工大学防震减灾研究所甘肃兰州730050 兰州理工大学西部土木工程防灾减灾教育部工程研究中心甘肃兰州730050

从构件安全层次考虑,提出了基于传力路径优化配置消能支撑的减震设计方法。采用广义结构刚度法计算结构系统中所有构件的重要性系数,在假定支撑截面参数后,取每层构件重要性系数最大的位置布置消能支撑,经支撑的最不利地震组合轴力验算... 详细信息

从构件安全层次考虑,提出了基于传力路径优化配置消能支撑的减震设计方法。采用广义结构刚度法计算结构系统中所有构件的重要性系数,在假定支撑截面参数后,取每层构件重要性系数最大的位置布置消能支撑,经支撑的最不利地震组合轴力验算确定支撑的最终参数和数目,并考虑远场、近场有脉冲、近场无脉冲地震动对结构的影响,对结构进行双向地震输入下的动力时程分析。计算结果表明,利用此方法布置支撑能有效保护在传力路径中占重要位置的构件,使消能支撑在小、中、大震下均能发挥良好性能,并能很好地控制整体结构响应。

关键词：传力路径减震设计广义结构刚度法构件重要性系数

Broadband and perfect terahertz absorber based on multilayer metamaterial with cross-ring patterned structures

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Optoelectronics Letters 2025年第1期21卷 1-6页

作者： wen Jin LIU Zhanzhi WU Zhengwei PAN Yu zhang Ying School of Science Xi'an Shiyou University Shaanxi Key Laboratory of Measurement and Control Technology for Oil and Gas Wells

Broadband and perfect terahertz absorber based on multilayer metamaterial using cross-ring patterned structures is proposed and investigated. The structure of the absorber is double absorption layers consisting of a chromium cross ring and eight isosceles right triangles. The unique structure of the double absorbing layers excites the electric dipole multimode resonance, giving rise to high absorption performance. Meanwhile, the influence of construal parameters on absorber behavior is also discussed. The numerical results show that the absorption achieves over 90% ranging from 2.45 THz to 6.25 THz and 99% absorption in the range of 3.7—5.3 THz. The realization of broadband and perfect absorber is described using the impedance matching principle. It is obviously found that the absorber is insensitive to the high angle of incidence for both transverse electric(TE) and transverse magnetic(TM) polarizations. Compared with the former reports, this absorber has remarkable improved absorption efficiency and smaller period. The terahertz absorber may be found applications in the fields of energy capture and thermal detection.

关键词： Metamaterials

The potential mechanism and clinical application value of remote ischemic conditioning in stroke

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Neural Regeneration Research 2025年第6期20卷 1613-1627页

作者： Yajun Zhu Xiaoguo Li Xingwei Lei Liuyang Tang Daochen wen Bo Zeng Xiaofeng zhang Zichao Huang Zongduo Guo The First Affiliated Hospital of Chongqing Medical University ChongqingChina

Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved.

关键词： Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke neuroinflammation neuroprotection Notch1 PI3K remote ischemic conditioning stroke

Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

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Neural Regeneration Research 2025年第4期20卷 1164-1177页

作者： Pengfei Wang Yuewei Bi Min Li Jiazhi Chen Zhuyong Wang Huantao wen Ming Zhou Minjie Luo Wangming zhang Neurosurgery Center Department of Pediatric NeurosurgeryGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Long-term levodopa administration can lead to the development of levodopa-induced *** oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced ***,studies have reported increased oscillation power in cases of levodopa-induced ***,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced ***,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is *** found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s ***,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma *** of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum ***,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum *** findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

关键词： aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials neuromodulation Parkinson’s disease primary motor cortex

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang wenwu zhang Gang Li Xing Cheng Peiqiang Su yong Wan Xiang Li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury