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Overview on Mangrove Forest Disaster Prevention and Mitigation Functions

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Journal of Ocean University of China 2024年第1期23卷 46-56页

作者： CHEN Xinping YIN Ziqi LI Zibin WANG Bin TAO Aifeng guo zhixing WANG Fei AN Yanhong O’DRISCOLL Kieran College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China National Marine Hazard Mitigation Service Beijing 100194China The People’s Government of Hainan Province Haikou 570204China Hibernian Marine Systems Limited Cork T12EDD8Ireland

This paper provides a comprehensive overview on coastal protection and hazard mitigation by *** stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protection function,including wave energy dissipation,storm surge damping,tsunami mitigation,adjustment to sea level rise and wind speed reduction,which are sys-tematically summarized in this ***,the study analyzes the extensive physical models,based on indoor flume experi-ments and numerical models,that consider the interaction between mangroves and hydrodynamics,to help our understanding of mangrove-hydrodynamic ***,quantitative approaches for valuing coastal protection services provided by man-groves,including index-based and process-resolving approaches,are introduced in ***,we point out the limitations of previous studies,indicating that efforts are still required for obtaining more long-term field observations during extreme weather events,to create more real mangrove models for physical experiments,and to develop numerical models that consider the flexible properties of mangroves to better predict wave propagation in mangroves having complex morphology and structures.

关键词： mangrove coastal protection disaster prevention and mitigation disaster reduction value coastal resilience

Design and preparation of gradient graphite/cermets self-lubricating composites

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Journal of Materials Science & Technology 2018年第8期34卷 1378-1386页

作者： Liming Zhou Ji Xiong zhixing guo Junliu Ye School of Manufacturing Science and Engineering Sichuan University

Based on the functionally graded materials （FGMs） design concept, the laminated-graded graphite/cermets self-lubricating composite was prepared to achieve the integration of mechanical prop- erties and lubrication performance of the cermet. The effects of the layer number and thickness of graded structure on residual stresses in the gradient composites were investigated by finite element method （FEM）. From the FEM analyses, the optimal gradient structure design was obtained correspond- ing to the following parameters： the number of graded layers n = 2 and the thickness of graded structure t = I ram. According to the optimum design, a graded graphite/cermets self-lubricating material with two layers was fabricated by a typical powder metallurgy technique. Compared with the homogenous graphite/cermets composite, the surface hardness and indentation fracture toughness of graded compos- ite were increased by approximately 15.9% and 6.3%, respectively. The results of X-ray diffraction （XRD） stress measurement identified the existence of residual compressive stress on the surface of graded com- posite. Additionally, the friction and wear tests revealed that the wear resistance of the graphite/cermets self-lubricating composite was improved significantly via the graded structural design, whereas the coefficient of friction changed slightly.

关键词： Graphite/cermets self-lubricating material Graded structure Finite element analysis Mechanical properties Tribological performance

KRAS mutation:from undruggable to druggable in cancer

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3466-3485页

作者： Lamei Huang zhixing guo Fang Wang Liwu Fu State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineGuangdong Esophageal Cancer InstituteSun Yat-Sen University Cancer CenterGuangzhou 510060P.R.China

Cancer is the leading cause of death worldwide,and its treatment and outcomes have been dramatically revolutionised by targeted *** the most frequently mutated oncogene,Kirsten rat sarcoma viral oncogene homologue(KRAS)has attracted substantial *** understanding of KRAS is constantly being updated by numerous studies on KRAS in the initiation and progression of cancer ***,KRAS has been deemed a challenging therapeutic target,even“undruggable”,after drugtargeting efforts over the past four ***,there have been surprising advances in directly targeted drugs for KRAS,especially in KRAS(G12C)inhibitors,such as AMG510(sotorasib)and MRTX849(adagrasib),which have obtained encouraging results in clinical ***,AMG510 was the first drug-targeting KRAS(G12C)to be approved for clinical use this *** review summarises the most recent understanding of fundamental aspects of KRAS,the relationship between the KRAS mutations and tumour immune evasion,and new progress in targeting KRAS,particularly KRAS(G12C).Moreover,the possible mechanisms of resistance to KRAS(G12C)inhibitors and possible combination therapies are summarised,with a view to providing the best regimen for individualised treatment with KRAS(G12C)inhibitors and achieving truly precise treatment.

关键词： KRAS precise truly

A Time-dependent Stochastic Grassland Fire Ignition Probability Model for Hulun Buir Grassland of China

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Chinese Geographical Science 2013年第4期23卷 445-459页

作者： guo zhixing FANG Weihua TAN Jun SHI Xianwu Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education National Marine Hazard Mitigation Service State Oceanic Administration State Key Laboratory of Earth Surface Processes and Resource Ecology Key Laboratory of Environmental Change and Natural Disaster Ministry of Education

Grassland fire is one of the most important disturbance factors in the natural *** paper focuses on the spatial distribution of long-term grassland fire patterns in the Hulun Buir Grassland located in the northeast of Inner Mongolia Autonomous Region in *** density or ratio of ignition can reflect the relationship between grassland fire and different ignition *** on the relationship between the density or ratio of ignition in different range of each ignition factor and grassland fire events,an ignition probability model was developed by using binary logistic regression function and its overall accuracy averaged up to 81.7%.Meanwhile it was found that daily relative humidity,daily temperature,elevation,vegetation type,distance to county-level road,distance to town are more important determinants of spatial distribution of fire *** Monte Carlo method,we developed a time-dependent stochastic ignition probability model based on the distribution of inter-annual daily relative humidity and daily *** this model,it is possible to estimate the spatial patterns of ignition probability for grassland fire,which will be helpful to the quantitative evaluation of grassland fire risk and its management in the future.

关键词： grassland fire binary logistic regression GIS spatial analysis ignition probability Monte Carlo method

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难治性高血压新型降压药物研究进展

河南医学研究 2024年第9期33卷 1720-1724页

作者：郭智星袁晓鹏高传玉郑州大学人民医院阜外华中心血管病医院心内科河南郑州450000 郑州大学人民医院阜外华中心血管病医院急诊科河南郑州450000

高血压是心血管疾病的主要危险因素,难治性高血压(RH)的危害性更大。近几年研发的诸如血管紧张素受体/脑啡肽酶抑制剂、非甾体类盐皮质激素受体拮抗剂、醛固酮合成酶抑制剂、肝血管紧张素原基因靶向调节药物、脑氨肽酶A抑制剂、双重内... 详细信息

高血压是心血管疾病的主要危险因素,难治性高血压(RH)的危害性更大。近几年研发的诸如血管紧张素受体/脑啡肽酶抑制剂、非甾体类盐皮质激素受体拮抗剂、醛固酮合成酶抑制剂、肝血管紧张素原基因靶向调节药物、脑氨肽酶A抑制剂、双重内皮素受体拮抗剂等新型药物,或许能为RH患者带来新的治疗方案。本文就上述药物的相关研究进行综述。

关键词：高血压难治性高血压新型降压药物

Effects of nano-Al_2O_3 and nano-ZrO_2 on the microstructure, behavior and abrasive wear resistance of WC-8Co cemented carbide

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Rare Metals 2011年第5期30卷 533-538页

作者： YANG Tian＇en XIONG Ji SUN Lan guo zhixing QIN Kangcai School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China

WC-8wt.% Co cemented carbides with varied nano-Al 2 O 3 and nano-ZrO 2 contents were prepared respectively following conventional powder metallurgical procedures. Effects of nano-Al 2 O 3 and nano-ZrO 2 on the microstructure, behavior, and abrasive wear resistance were investigated. The result shows that a finer and more homogenous microstructure can be achieved by increasing nano-Al 2 O 3 , and increasing nano-ZrO 2 makes the microstructure more refined. Nano-Al 2 O 3 and nano-ZrO 2 could both help to give increased hardness. Transverse rupture strength is higher if the above nano-oxides are doped appropriately, whereas excess addition is deleterious. Abrasive wear resistance presents different variations with respect to increasing nano-Al 2 O 3 and nano-ZrO 2 . By contrast, increasing nano-ZrO 2 enhances the abrasive wear resistance more effectively than increasing nano-Al 2 O 3 . The influence of the two nano-oxides contents on the abrasive wear resistance does not almost vary with wear time, and the optimum addition level of nano-Al 2 O 3 in WC-8% Co cemented carbide is 0.3 wt.% from the stand of abrasive wear resistance. In addition, both of the nano-oxides can retard the increase of wear rate in long-term abrasive wear.

关键词： cemented carbides microstructure abrasion wear resistance oxides mechanical properties

A Homogeneous Cloud Task Distribution Method Based on an Improved Leapfrog Algorithm

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Computer Modeling in Engineering & Sciences 2021年第7期128卷 359-379页

作者： Yunliang Huo Ji Xiong zhixing guo Qianbing You Yi Peng School of Mechanical Engineering Sichuan UniversityChengdu610065China Chengdu Yigao Intelligent Technology Co. Ltd.Chengdu610065China

Cloud manufacturing is a new manufacturing model with crowd-sourcing characteristics,where a cloud alliance composed of multiple enterprises,completes tasks that a single enterprise cannot accomplish by ***,compared with heterogeneous cloud tasks,there are relatively few studies on cloud alliance formation for homogeneous *** bridge this gap,a novel method is presented in this ***,a homogeneous cloud task distribution model under cloud environment was constructed,where services description,selection and combination were *** improved leapfrog algorithm for cloud task distribution(ILA-CTD)was designed to solve the proposed *** from the current alternatives,the initialization operator and the leapfrog operator in ILA-CTD can ensure that the algorithm always searches the optimal solution in the feasible ***,the processing of task allocation for 1000 pieces of medical labeling machine bottom plates was studied as a case to show the feasibility of the proposed *** superiority of ILA-CTD was also proven based on more optimal solutions found,compared with the three other methods.

关键词： Cloud manufacturing service composition tasks distribution intelligent optimization leapfrog algorithm

Microstructure and Properties of Gradient Cemented Carbide with Nano-TiN

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Journal of Wuhan University of Technology(Materials Science) 2014年第1期29卷 102-108页

作者：杨天恩 SUN Lan 熊计 guo zhixing ZHENG Xiaoming School of Manufacturing Science and Engineering Sichuan University

Gradient cemented carbides with nano-TiN were prepared by the common powder metallurgical procedure. The formation of gradient zone and the microstructure, properties of the alloys were investigated using scanning electron microscope（SEM）, energy dispersive spectroscopy（EDS） and other performance testing apparatus. Moreover, the effect of nano-TiN on the gradient cemented carbide was studied. It is found that gradient zone width increases slightly with nano-TiN introduction. Both cobalt and titanium concentrations reach the maximum near the gradient border. Tungsten concentration shows fluctuation from the surface to the bulk. （Ti ,W）C phase grains are refined for nitrogen introduction. Core-rim structure has been observed under the SEM back-scattered mode. The core appears as dark due to more titanium in it and the rim with more tungsten appears as grey. In addition, the hardness and transverse rupture strength of gradient cemented carbide are enhanced with nano-TiN introduced.

关键词： gradient cemented carbide cubic phase nano-TiN core-rim structure

急性冠脉综合征患者氯吡格雷高血小板反应性临床预测模型的建立及验证

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中国心血管杂志 2024年第5期29卷 404-411页

作者：郭智星袁晓鹏朱彬彬刘亚慧贺博高传玉郑州大学人民医院阜外华中心血管病医院心内科450003 郑州大学人民医院阜外华中心血管病医院急诊科450003

目的在急性冠脉综合征(ACS)患者中构建并验证氯吡格雷高血小板反应性(HPR)的临床预测模型。方法单中心、回顾性研究。连续纳入2019年1月1日至2022年11月30日在郑州大学人民医院阜外华中心血管病医院接受治疗的242例ACS患者作为研究对象... 详细信息

目的在急性冠脉综合征(ACS)患者中构建并验证氯吡格雷高血小板反应性(HPR)的临床预测模型。方法单中心、回顾性研究。连续纳入2019年1月1日至2022年11月30日在郑州大学人民医院阜外华中心血管病医院接受治疗的242例ACS患者作为研究对象。采用简单随机抽样法按6∶4分为训练集144例和验证集98例。筛选出氯吡格雷HPR的独立危险因素,建立预测模型并绘制Nomogram图。在训练集和验证集中,分别采用受试者工作特征(ROC)曲线、Bootstrap自抽样法、Hosmer-Lemeshow拟合优度检验和决策曲线分析(DCA)对预测模型进行区分度、校准度和临床实用度评估。结果Logistic回归分析显示,CYP2C19基因多态性、体质指数(BMI)≥28 kg/m^(2)、平均血小板体积(MPV)≥10.85 fL和低密度脂蛋白胆固醇(LDL-C)≥2.6 mmol/L是ACS患者发生氯吡格雷HPR的独立危险因素。将上述4项指标纳入回归方程构建预测模型并绘制Nomogram图。在训练集和验证集中采用ROC曲线对模型进行区分度检验,曲线下面积(AUC)分别为0.757(95%CI:0.676~0.840)和0.750(95%CI:0.646~0.854);采用Bootstrap自抽样法抽样1000次对模型进行内部验证,矫正后的C-Statistic分别为0.732(95%CI:0.656~0.820)和0.725(95%CI:0.632~0.827);进行Hosmer-Lemeshow检验,P值分别为0.954和0.097;进行DCA检验显示,模型的临床净获益范围分别为20.20%~97.95%和19.31%~78.92%。结论ACS患者出现氯吡格雷HPR的独立危险因素为CYP2C19基因多态性、BMI≥28 kg/m^(2)、MPV≥10.85 fL和LDL-C≥2.6 mmol/L。本研究建立的Nomogram图在区分度、校准度和临床实用度三个方面表现良好,可作为临床预测工具,为基层医生调整双抗方案提供便利。

关键词：急性冠脉综合征氯吡格雷高血小板反应性危险因素预测模型

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