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Petrogenesis and tectonic implications of the Early Cretaceous Dagushan adakitic porphyries in the Anshan area,North China Craton

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Acta Geochimica 2022年第1期41卷 24-38页

作者： Xiaohui Sun Haoshu Tang yan Luan Key Laboratory of Western China’s Mineral Resources and Geological Engineering MOESchool of Earth Science and ResourcesChang’an UniversityXi'an 710054China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The eastern part of the North China Craton suffered significant lithospheric thinning since the Mesozoic,and petrogenesis of the Dagushan adakitic diorite porphyries provides an excellent opportunity to investigate the lithospheric thinning mechanism and geodynamic *** zircon LA-ICP-MS U–Pb geochronology reveals that the representative Dagushan adakitic porphyry was formed at 120.5±0.5 *** Dagushan diorite porphyries are characterized by the relatively high contents of SiO_(2)(64.25–65.70 wt%),Al_(2) O_(3)(15.00–15.38 wt%),Sr(333–491 ppm),low contents of Y(6.50–10.3 ppm),and Yb(0.57–0.85 ppm),and resultant high Sr/Y(47–57)and La/Yb(37–55)ratios,exhibiting geochemical characteristics of typical ***,the relatively high Mg O contents(MgO=2.23–2.29 wt%)and Mg numbers(Mg^(#)-=54–56)of the Dagushan adakitic rocks imply that the pristine adakitic magma interacted with mantle ***,the zircon Hf isotopic signatures(εHf(t)=-19.0 to-28.0;TDM2=2378–2944 Ma)suggest an ancient lower crustal ***,it is proposed that the Dagushan adakitic rock was probably generated by partial melting of delaminated lower crust which was triggered by the Tan-Lu Fault Zone,and the interaction of pristine adakitic magma with mantle peridotite during the ascent finally generated the Dagushan high Mg^(#)adakitic *** is suggested that delamination was an important mechanism for lithospheric thinning of the NCC.

关键词： Diorite porphyry Adakite Lower crust Delamination NCC

Trajectory prediction of ballistic missiles using Gaussian process error model

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Chinese Journal of Aeronautics 2022年第1期35卷 458-469页

作者： Ruiping JI yan LIANG Linfeng XU Zhenwei WEI School of Automation Northwestern Polytcchnical UniversityXi'an 710129China Key Laboratory of Information Fusion Technology Ministry of EducationXi'an 710129China

Ballistic Missile Trajectory Prediction(BMTP)is critical to air defense *** Trajectory Prediction(TP)methods focus on the coast and reentry phases,in which the Ballistic Missile(BM)trajectories are modeled as ellipses or the state components are propagated by the dynamic integral equations on time *** contrast,the boost-phase TP is more challenging because there are many unknown forces acting on the BM in this *** tackle this difficult problem,a novel BMTP method by using Gaussian Processes(GPs)is proposed in this *** particular,the GP is employed to train the prediction error model of the boost-phase trajectory database,in which the error refers to the difference between the true BM state at the prediction moment and the integral extrapolation of the BM *** the final BMTP is a combination of the dynamic equation based numerical integration and the GP-based prediction *** the trained GP aims to capture the relationship between the numerical integration and the unknown error,the modified BM state prediction is closer to the true one compared with the original ***,the GP is able to output the uncertainty information of the TP,which is of great significance for determining the warning range centered on the predicted BM *** results show that the proposed method effectively improves the BMTP accuracy during the boost phase and provides reliable uncertainty estimation boundaries.

关键词： Ballistic missile Boost-phase trajectory State prediction Gaussian processes Uncertainty estimation

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考虑站点分类的城市轨道短时客流预测方法

计算机工程与应用 2024年第19期60卷 343-353页

作者：王泰州徐金华陈姜会李岩任璐长安大学运输工程学院西安710064 长安大学学术期刊管理中心西安710064

精确、可靠的短时客流预测可为城市轨道交通运营提供保障。考虑不同站点的客流时序特征差异,在对站点分类的基础上,建立了一种城市轨道站点客流的深度学习预测方法。以动态时间规整及K-means算法对站点进行分类,分析各类站点的客流时序... 详细信息

精确、可靠的短时客流预测可为城市轨道交通运营提供保障。考虑不同站点的客流时序特征差异,在对站点分类的基础上,建立了一种城市轨道站点客流的深度学习预测方法。以动态时间规整及K-means算法对站点进行分类,分析各类站点的客流时序特征;采用自适应噪声完全集成经验模式分解算法对各类站点客流数据进行分解,以减少数据噪声的影响;提出一种融合长短期记忆网络和Transformer模型的深度学习预测方法,从而预测不同类型站点客流。应用西安市轨道交通客流数据验证该方法,结果表明:根据工作日及非工作日的客流数据时序特征可将站点分为职住均衡型、商务办公型、休闲娱乐型和密集居住型4类,所提出的方法在不同类型站点的客流预测结果相比于其他3种单一模型和3种组合模型,平均绝对误差降低16.36%~51.02%、均方根误差降低10.35%~50.76%,平均绝对百分比误差降低14.71%~48.62%,基于15 min、30 min、45 min及60 min不同时间间隔统计的站点客流数据的预测结果相比于其他6种模型,3种指标分别降低了12.63%~51.02%、8.08%~49.12%和6.83%~47.26%。

关键词：城市轨道交通短时预测站点分类自适应噪声完全集成经验模式分解算法长短期记忆网络 Transformer

两样本双向孟德尔随机化分析胃食管反流病与偏头痛间的因果效应

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西安交通大学学报（医学版） 2024年第2期45卷 262-270页

作者：马佳昕周元植陈雯雯赵雅涵张旭李雅睿和水祥赵艳西安交通大学第一附属医院消化内科陕西西安710061 陕西省消化系统疾病(肿瘤方向)临床医学研究中心陕西西安710061

目的利用两样本双向孟德尔随机化(MR)研究方法,探讨胃食管反流病与偏头痛之间发病的因果关联,为两种疾病发病风险关联提供遗传学证据支持。方法从公开发表的全基因组关联分析(GWAS)数据库中获取两样本的单核苷酸多态性(SNP)信息,筛选出... 详细信息

目的利用两样本双向孟德尔随机化(MR)研究方法,探讨胃食管反流病与偏头痛之间发病的因果关联,为两种疾病发病风险关联提供遗传学证据支持。方法从公开发表的全基因组关联分析(GWAS)数据库中获取两样本的单核苷酸多态性(SNP)信息,筛选出合适的SNP作为工具变量,利用逆方差加权法(IVW)、加权中位数法(WM)、MR-Egger回归法、加权众数法以及简单模型法五种MR分析方法进行双向MR分析,并进行敏感性检验。结果IVW显示以胃食管反流病为暴露的正向MR分析结果有阳性意义[OR=1.3987,95%CI(1.1817~1.6556),P=9.59×10^(-5)],以偏头痛为暴露的反向MR分析结果无阳性意义(P>0.05),在除MR-Egger外的其他方法中得到相同的结论。正向MR(P=0.92)与反向MR(P=0.64)均未发现工具变量具有水平多效性,留一法剔除单个SNP后结果具有稳健性。结论胃食管反流病与偏头痛之间可能存在单向的因果关联,胃食管反流病是偏头痛发病的危险因素。

关键词：胃食管反流病偏头痛孟德尔随机化因果关系危险因素

融合图卷积与Transformer的三维人体姿态估计网络

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自动化应用 2024年第13期65卷 71-75,86页

作者：闫永杰李敏奇西安工程大学电子信息学院陕西西安710600

两阶段的3D人体姿态估计方法因先进的2D姿态检测器而取得了显著进步,但深度信息的歧义性仍使这项任务极具挑战性。为解决此难题,提出了MGCNTrans的3D人体姿态估计网络。该方法采用2D-3D的提升策略。MGCNTrans网络融合了Transformer网络... 详细信息

两阶段的3D人体姿态估计方法因先进的2D姿态检测器而取得了显著进步,但深度信息的歧义性仍使这项任务极具挑战性。为解决此难题,提出了MGCNTrans的3D人体姿态估计网络。该方法采用2D-3D的提升策略。MGCNTrans网络融合了Transformer网络和空间通道图卷积网络的优势。该模型以多帧数据为输入,利用周围帧的信息来约束当前帧的姿态估计。在特征学习方面,图卷积网络被用于学习人体关节之间的物理连接关系,捕捉局部的空间特征。而Transformer网络则挖掘关节之间的隐式关系,提供全局的上下文信息。为提升模型性能,图卷积层融合了空间层和通道层,促使节点在局部和全局范围内更好地进行交互,增加特征多样性,并更准确地估计人体姿态。结果表明,MGCNTrans网络在3D人体姿态估计任务上取得了优越性能,证明了其有效性和先进性。

关键词：三维人体姿态估计图卷积网络 Transformer网络

远志皂苷通过TLR4/NF-κB信号通路对高糖诱导的肾小管上皮细胞损伤的机制

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中国老年学杂志 2024年第9期44卷 2152-2156页

作者：杜燕陈钊魏琳婷付荣国崔晨凯西安医学院第一附属医院肾内科陕西西安710048 西安交通大学第二附属医院肾内科

目的探讨远志皂苷(Ten)对高糖诱导的人肾小管上皮HK-2细胞损伤的影响及其对Toll样受体(TLR)4/核转录因子(NF)-κB信号通路的调控机制。方法高糖诱导HK-2细胞糖尿病肾病模型,不同浓度Ten处理HK-2细胞,噻唑蓝(MTT)法筛选Ten适宜浓度;实验... 详细信息

目的探讨远志皂苷(Ten)对高糖诱导的人肾小管上皮HK-2细胞损伤的影响及其对Toll样受体(TLR)4/核转录因子(NF)-κB信号通路的调控机制。方法高糖诱导HK-2细胞糖尿病肾病模型,不同浓度Ten处理HK-2细胞,噻唑蓝(MTT)法筛选Ten适宜浓度;实验分为NG组、HG组、HG+Ten组、HG+Ten+pcDNA组、HG+Ten+TLR4组;流式细胞术检测凋亡率;试剂盒检测丙二醛(MDA)、活性氧(ROS)水平与超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性;Western印迹检测TLR4、p-p65、p65、B细胞淋巴瘤(Bcl)-2、Bcl-2相关X蛋白(Bax)表达量。结果MTT检测结果显示,选用Ten 150μmol/L进行后续实验;与NG组比较,HG组凋亡率、TLR4、Bax、TLR4、p-p65蛋白、MDA、ROS水平明显升高,Bcl-2蛋白水平、SOD、GSH-Px活性明显降低(P<0.05);与HG组比较,HG+Ten组凋亡率、Bax、TLR4、p-p65蛋白、MDA、ROS水平明显降低,Bcl-2蛋白水平、SOD、GSH-Px活性明显升高(P<0.05);与HG+Ten+pcDNA组比较,HG+Ten+TLR4组凋亡率、TLR4、Bax蛋白、MDA、ROS水平明显升高,Bcl-2蛋白水平、SOD、GSH-Px活性明显降低(P<0.05)。结论Ten可通过抑制TLR4/NF-κB信号通路激活而减轻高糖诱导的HK-2细胞损伤。

关键词：远志皂苷糖尿病肾病 Toll样受体(TLR)4/核转录因子(NF)-κB 人肾小管上皮细胞细胞凋亡

矿物解理/断裂规律与晶面间距的弱相关性及证明

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岩石矿物学杂志 2024年第4期43卷 931-937页

作者：王纪镇张佳祺闫荣禄陈友良李甲伟西安科技大学化学与化工学院陕西西安710054

应用密度泛函理论、断裂键理论和晶体化学性质,定量研究了矿物解理/断裂的晶体化学机制以及与晶面间距(或面网间距)的关系。归纳发现,矿物常见解理/断裂面并不总是与晶面间距最大的晶面相对应,体现为弱相关性。理论计算结果表明,矿物常... 详细信息

应用密度泛函理论、断裂键理论和晶体化学性质,定量研究了矿物解理/断裂的晶体化学机制以及与晶面间距(或面网间距)的关系。归纳发现,矿物常见解理/断裂面并不总是与晶面间距最大的晶面相对应,体现为弱相关性。理论计算结果表明,矿物常见解理/断裂面对应于表面能最低的晶面,而表面能与面网密度及晶面原子平均断裂键数τ正相关。晶面间距与面网密度正相关,意味着当晶面间距大的晶面成为常见解理/断裂面时,需通过降低晶面原子平均断裂键数τ值以降低表面能。然而,通过分析发现,晶面间距与晶面原子平均断裂键数τ的关联性差,从而使得晶面间距与矿物解理/断裂规律无直接关联性。本文的研究结果能够为矿物解理/断裂规律以及表面性质研究提供理论借鉴。

关键词：晶面间距矿物解理/断裂表面能断裂键参数弱相关性

Perovskite–A wonder catalyst for solar hydrogen production

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Journal of Energy Chemistry 2021年第6期30卷 325-340,I0008页

作者： Hui Bian Deng Li Junqing yan Shengzhong(Frank)Liu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationChina Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina Dalian National Laboratory for Clean Energy China iChEM Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental *** all the materials utilized for solar hydrogen production,perovskite has emerged as a rising star due to its superior optoelectronic *** manuscript aims to provide a comprehensive review summarizing the recent inspiring advancements on perovskite-based solar hydrogen production systems,including the particulate photocatalysis,photoelectrochemical cells,and photovoltaic-electrocatalytic *** start with a brief introduction of the advantages of perovskites for solar hydrogen production and the basic principles of the three most prominent solar hydrogen production *** representative progresses in this field are then detailed with a special emphasis on the strategies to improve the efficiency and the stability of the ***,challenges and opportunities for the further development of the PVK-based solar hydrogen production systems are presented with perspective given on outlook,performance,cost and stability.

关键词： Perovskite Solar hydrogen production Photocatalysis Photoelectrocatalysis Photovoltaic-electrocatalysis

Physiological mechanisms of resistance to cold stress associated with 10 elite apple rootstocks

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Journal of Integrative Agriculture 2018年第4期17卷 857-866页

作者： WANG yan-xiu HU Ya CHEN Bai-hong ZHU yan-fang Mohammed Mujitaba Dawuda Sofkova Svetla College of Horticulture Gansu Agricultural University Deparment of Horticulture Faculty of Agriculture University for Development Studies Institute of Agriculture and Environment Massey University

A study was conducted in attempting to identify the cold-resistant apple rootstocks and to establish a comprehensive evaluation system. In this study, 10 elite apple dwarfing rootstocks(GM256, jm7, M26, M7, SC1, SH1, SH38, SH6, M9, and T337) were employed for the experiment and the following parameters were investigated under different low temperature stress conditions(0, –15, –20, –25, –30, and –35°C): the changes of the relative electrical conductivity(REC), anthocyanin content, protein content, soluble sugar content, soluble starch content, proline content, malondialdehyde(MDA) content, superoxide dismutase(SOD) activity, and peroxidase(POD) activity of the dormant branches. The inflection temperature that could represent the plant tissue semi-lethal temperature(LT) was obtained by the measurements of REC. The LTwas used to evaluate eight other indices. The results showed that there was no significant correlation between LTand POD activity as well as between the soluble sugar, protein and proline contents at 0 and –15°C. Soluble starch content at 0 and –15°C and anthocyanin content at –15–(–30)°C were significantly but negatively correlated to the LT50 and the MDA content at 0–(–20)°C was significantly positively correlated to the LT. Statistical analysis based on principal component analysis and LT50 showed that cold resistant apple rootstocks in the decreasing order from high to low as GM256, SH6, SH38, SH1, SC1, M26, M7, jm7, T337, and M9.

关键词： cold resistance LT_(50) principal component analysis apple dwarfing rootstock