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裂隙岩体三维随机裂隙建模与渗流数值仿真研究

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计算力学学报 2024年第4期41卷 718-725页

作者：季慧王鲁瑀吴则祥涂冬媚中国人民解放军32576部队广州510110 香港理工大学土木与环境工程学院香港999077 温州大学建筑工程学院温州325000 温州理工学院建筑与能源工程学院温州325000

裂隙岩体数值仿真是研究工程岩体稳定性的重要方法之一,本文围绕三维裂隙岩体随机裂隙建模和渗流仿真展开研究.针对三维裂隙空间定量表征问题,基于空间解析几何方法导出三维裂隙产状控制方程,在此基础上发展了随机裂隙生成算法和网格剖... 详细信息

裂隙岩体数值仿真是研究工程岩体稳定性的重要方法之一,本文围绕三维裂隙岩体随机裂隙建模和渗流仿真展开研究.针对三维裂隙空间定量表征问题,基于空间解析几何方法导出三维裂隙产状控制方程,在此基础上发展了随机裂隙生成算法和网格剖分方案,为裂隙可视化和生成裂隙单元提供基础;讨论了一种处理三维交叉裂隙的方法,从而降低网格单元扭曲度.进一步,采用裂隙孔隙双重介质渗流模型,对三维裂隙岩体进行渗流仿真,通过算例展示了几种不同的裂隙分布形式及其网格剖分结果,分析了三维交叉裂隙模型和随机裂隙模型的渗流特性.

关键词：裂隙岩体渗流数值方法三维建模

砂土中吸力筒基础抗拔数值模拟研究:系泊深度效应

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岩土力学 2024年第7期45卷 2187-2194页

作者：季慧彭宇吴则祥涂冬媚中国人民解放军32576部队广东广州510110 香港理工大学土木与环境工程学院中国香港999077 温州大学建筑工程学院浙江温州325000 温州理工学院建筑与土木工程学院浙江温州325000

针对锚线斜拉作用下吸力筒与砂土相互作用的微观特征仍不清楚这一问题,采用离散元(discrete element method,简称DEM)-有限元(finite element method,简称FEM)耦合数值方法,从宏观到微观角度分析系泊点深度对吸力筒基础抗拔性能的影响... 详细信息

针对锚线斜拉作用下吸力筒与砂土相互作用的微观特征仍不清楚这一问题,采用离散元(discrete element method,简称DEM)-有限元(finite element method,简称FEM)耦合数值方法,从宏观到微观角度分析系泊点深度对吸力筒基础抗拔性能的影响。在建模中,采用FEM中有限元网格来模拟吸力筒,采用DEM中颗粒来模拟吸力筒周围砂土,并通过控制滚轴运动来模拟锚线的拉作用。结果表明:吸力筒的拉力-位移曲线存在峰值拉力,且与不同系泊点深度下吸力筒运动模式有密切关系;吸力筒旋转方向、拔出位移的反转临界系泊深度点位于吸力筒从顶部往下h=66.7%深度附近(即吸力筒深度的2/3处,h为系泊深度)。此外,从颗粒尺度分析了土体变形及破坏行为,最终确定了吸力筒-颗粒土相互作用的破坏模式。研究结果表明,忽略锚线的系泊点深度将会导致误判吸力筒的承载能力及与土体的破坏模式。

关键词：吸力筒抗拔 DEM-FEM耦合深度效应土体变形

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食管癌地域性差异研究进展

肿瘤防治研究 2024年第6期51卷 488-494页

作者：陈瑜蔡文科罗小迪贺永能涂东解放军联勤保障部队第920医院心胸外科昆明650032

食管癌是一种常见的消化道恶性肿瘤,显著的地域性差异是食管癌临床流行病学突出特征之一,主要表现在发病率、发病类型、发病年龄和基因突变等方面,这些差异可能与人们的饮食习惯、生活方式、环境因素等有关。近年来关于食管癌地域性差... 详细信息

食管癌是一种常见的消化道恶性肿瘤,显著的地域性差异是食管癌临床流行病学突出特征之一,主要表现在发病率、发病类型、发病年龄和基因突变等方面,这些差异可能与人们的饮食习惯、生活方式、环境因素等有关。近年来关于食管癌地域性差异的研究逐渐深入,因此,本文将对食管癌在不同地域,包括亚洲(中国、印度、日本等)、欧洲、美洲(美国)、非洲等的发病率、发病类型、基因突变、表观遗传学、风险因素、预后等差异进行概述,帮助医生和公共卫生专家更好地了解食管癌的风险因素和病因,进而制定更加有效的预防和治疗策略,减少食管癌的发生和死亡率。

关键词：食管癌地域差异性发病率基因突变风险因素

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恶性胸膜间皮瘤化疗抵抗机制研究进展

肿瘤防治研究 2024年第8期51卷 690-696页

作者：张利于杰陈瑜罗小迪汪继翠涂东解放军联勤保障部队第920医院心胸外科昆明650032

恶性胸膜间皮瘤(MPM)是一种发病率不高,但侵袭性强、预后差、致死率高的肿瘤,生存期为4个月~1年,5年生存率仅为10%左右。MPM具有很强的化疗抵抗性,顺铂联合培美曲塞或者雷替曲塞的常规治疗只在20%左右患者中有一定的效果。近年来,随着对... 详细信息

恶性胸膜间皮瘤(MPM)是一种发病率不高,但侵袭性强、预后差、致死率高的肿瘤,生存期为4个月~1年,5年生存率仅为10%左右。MPM具有很强的化疗抵抗性,顺铂联合培美曲塞或者雷替曲塞的常规治疗只在20%左右患者中有一定的效果。近年来,随着对MPM遗传特征研究的不断深入,对MPM化疗抵抗分子机制的研究也取得一定进展。本文总结了近年来MPM化疗抵抗分子机制的研究进展,包括BAP1基因突变、MicroRNA、MTA1介导的DNA损伤修复通路、GITR-GITRL通路、TGFa通路、肿瘤干细胞、EGFR、PTEN等,旨在为探索MPM新治疗靶点、新联合治疗方案提供参考。

关键词：恶性胸膜间皮瘤化疗抵抗分子机制

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang Song Chen Xin dong tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

Experimental study on effects of gas flow rate on soot characteristics in diffusion flames coupled with plasma

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Science China(Technological Sciences) 2024年第2期67卷 475-485页

作者： QI DanDan CHEN MingXiao tu Xin LIU dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study examined the evolution of morphology and nanostructure of soot particles from the plasma-flame interaction for various gas flow *** current study used both optical diagnostic and sampling methods to explore the soot production and combustion *** particles were characterized at the same positions downstream from the flame zone by thermophoretic sampling and transmission electron ***,X-ray diffraction analysis,and thermogravimetric analysis were performed to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasma addition,which illustrated an inhibition effect of plasma on soot *** increased gas flow rate promoted soot concentration since a growing number of carbons participated in the combustion *** on the gas flow rate(carbon content)variation and plasma activation,either liquid-like soot material with irregularly shaped protrusions or chain-like structure,or a mixture of both,were generated from the diffusion *** soot produced by plasma-flame interaction also demonstrated a high correlation between nanostructure and *** soot from lower carbon content with plasma activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation *** the contrary,soot from the highest carbon content without plasma-flame interaction exhibited prevalent fullerene-like nanostructures with evident large or small shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasma diffusion flames

Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)

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Horticultural Plant Journal 2024年第1期10卷 15-24页

作者： Qian Wang dong Huang Wenyan tu Fengwang Ma Changhai Liu State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains *** this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple ***,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with *** Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related *** overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected *** results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes *** jointly contributed to GLS resistance in apple.

关键词： Apple MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity Auxin Salicylic acid Jasmonic acid

Complicated Bosworth fracture-dislocation:A case report and review of the literature

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Chinese Journal of Traumatology 2023年第6期26卷 344-350页

作者： dong-Peng tu Li-Jun Cai Hong-Yong Zhao Li-Gang Huang Jing Nie Department of Orthopaedics Hangzhou Xiaoshan Orthopaedic Hospital of Traditional Chinese MedicineHangzhou311261China

Bosworth fracture and dislocation is relatively rare,accounting for about 1%of ankle *** is characterized by the proximal fibula fracture embedded in the posterolateral distal *** to an insufficient understanding of this fracture,it is easy to cause missed diagnosis and misdiagnosis in clinical *** to the insertion of the fracture,it is challenging to perform closed reduction,and improper treatment is easy to cause *** treatment is recommended for this type of *** order to improve the understanding of orthopedic surgeons about Bosworth fracture and dislocation,this paper reports the diagnosis and treatment of 2 cases of Bosworth fracture and dislocation,and reviews the literature on Bosworth fracture's mechanism,diagnosis,classification,complications,and treatment options in recent years.

关键词： Bosworth fracture Ankle fractures Fracture-dislocation

Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

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Plant Diversity 2024年第2期46卷 238-246页

作者： Shengchun Li Tieyao tu Shaopeng Li Xian Yang Yong Zheng Liang-dong Guo Dianxiang Zhang Lin Jiang Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China ECNU-Alberta Joint Lab for Biodiversity Study Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China School of Biological Sciences Georgia Institute of TechnologyAtlantaGA 30332USA Jiangxi Academy of Forestry Nanchang 330032China Institute of Eco-Chongming(IEC) Shanghai 202162China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain ***,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China *** found positive plant species-area relationships for both coral and continental ***,our results showed that different mechanisms contributed to similar plant species-area relationships between the two *** coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species *** contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental ***,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two *** summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental *** generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

关键词： Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect