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OSAHS患者超声心动图与多导睡眠监测结果的相关性

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河北医药 2024年第12期46卷 1818-1821页

作者：徐志琴朱嵘南京医科大学第二附属医院心内科南京市210011 南京医科大学第二附属医院急诊科南京市210011

目的探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者超声心动图与多导睡眠监测结果的相关性。方法回顾性收集2021年8月至2023年2月行多导睡眠监测的患者73例。根据呼吸暂停-低通气指数(AHI)值将患者分为轻度组(5≤AHI<15,29例),中度组... 详细信息

目的探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者超声心动图与多导睡眠监测结果的相关性。方法回顾性收集2021年8月至2023年2月行多导睡眠监测的患者73例。根据呼吸暂停-低通气指数(AHI)值将患者分为轻度组(5≤AHI<15,29例),中度组(15≤AHI<30,15例)和重度组(AHI≥30,29例)。收集患者基本临床资料(性别、年龄、吸烟、饮酒、常规生化、既往病史),多导睡眠监测结果(AHI、OAHI、ODI、RERA),超声心动图(LAD、RAD、IVS、LVPW、LVEF)。比较3组患者基本临床资料、多导睡眠监测结果、超声心动图的差异,并探究超声心动图与多导睡眠监测结果之间的相关性。结果3组患者基本临床资料中重度组高血压患病率高于中度组和轻度组,差异有统计学意义(均P<0.05);3组患者任意2组患者AHI、OAHI和ODI之间的差异有统计学意义(均P<0.05),重度组与中度组、重度组与轻度组RERA差异有统计学意义(均P<0.05);3组患者超声心动图重度组与中度组患者IVS和LVPW差异有统计学意义(均P<0.05),重度组与轻度组患者LAD、IVS和LVPW差异有统计学意义(均P<0.05)。相关性分析LAD、IVS和LVPW分别与AHI、OAHI、ODI均呈正相关(P<0.05),仅LVPW与RERA呈正相关(P<0.05)。结论OSAHS患者超声心动图与多导睡眠监测结果随病情的加重变化显著。其中,LAD、IVS和LVPW分别与AHI、OAHI、ODI均呈正相关,对于临床OSAHS患者病情评估及预后的判断具有重要的指导意义。

关键词：阻塞性睡眠呼吸暂停低通气综合征多导睡眠监测超声心动图相关性分析

Late Triassic Granites From the Quxu Batholith Shedding a New Light on the Evolution of the Gangdese Belt in Southern Tibet

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 462-481页

作者： MENG Yuanku xu zhiqin xu Yang MA Shiwei College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 Shandong China Key Laboratory of Depositional Mineralization and Sedimentary Mineral of Shandong province Qingdao 266599 Shandong China Qingdao Institute of Marine Geology China Geological Survey Qingdao 266061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China School of Earth Sciences andEngineering Nanjing University Nanjing 210023 China

The Gangdese magmatic belt formed during Late Triassic to Neogene in the southernmost Lhasa terrane of the Tibetan plateau. It is interpreted as a major component of a continental margin related to the northward subduction of the Neo-Tethys oceanic slab beneath Eurasia and it is the key in understanding the tectonic framework of southern Tibet prior to the India-Eurasia collision. It is widely accepted that northward subduction of the Neo-Tethys oceanic crust formed the Gangdese magmatic belt, but the occurrence of Late Triassic magmatism and the detailed tectonic evolution of southern Tibet are still debated. This work presents new zircon U-Pb-Hf isotope data and whole-rock geochemical compositions of a mylonitic granite pluton in the central Gangdese belt, southern Tibet. Zircon U-Pb dating from two representative samples yields consistent ages of 225.3~=1.8 Ma and 229.9~1.5 Ma, respectively, indicating that the granite pluton was formed during the early phase of Late Triassic instead of Early Eocene （47-52 Ma） as previously suggested. Geochemically, the mylonitic granite pluton has a sub-alkaline composition and low-medium K calc-alkaline affinities and it can be defined as an I-type granite with metaluminous features （A/CNK〈I.1）. The analyzed samples are characterized by strong enrichments of LREE and pronounced depletions of Nb, Ta and Ti, suggesting that the granite was generated in an island-arc setting. However, the use of tectonic discrimination diagrams indicates a continental arc setting. Zircon Lu-Hf isotopes indicate that the granite has highly positive till（t） values ranging from ＋13.91 to ＋15.54 （mean value ＋14.79）, reflecting the input of depleted mantle material during its magmatic evolution, consistent with Mg# numbers. Additionally, the studied samples also reveal relatively young Hf two-stage model ages ranging from 238 Ma to 342 Ma （mean value 292 Ma）, suggesting that the pluton was derived from partial melting of juvenile crust. Geochemical dis

关键词： Late Triassic Neo-Tethys Ocean active continental margin Gangdese batholith southern Tibet

Pseudotachylyte-Induced Weakness of Plate-Boundary Fault:Insight from the Indus-Tsangpo Suture between India and Asia

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 1-11页

作者： xu zhiqin JI Shaocheng ZHOU Xin School of Earth Sciences and Engineering Nanjing University Département des Génies Civil Géologique et des Mines école Polytechnique de Montréal Institute of Geology Chinese Academy of Geological Sciences

Although the Indus-Tsangpo Suture(ITS) is the most spectacular thrust system of continent-continent collision in the world, fundamental questions about its strength evolution and deformation behavior transition remain unanswered. Here we reported, for the first time, frictional melting-induced pseudotachylytes in the intensively deformed felsic rocks along the ITS zone in southern Tibet. This study reveals that pseudotachylytes induced profound weakness of the boundary fault between Indian and Asian plates. The intrinsically low strength of the foliated microlites crystallized from frictional melt or glass(i.e., pseudotachylyte) at seismogenic depths compared with the surrounding coarse-grained quartzofeldspathic rocks in the brittle and semi-brittle regime is sufficient to explain the localization of shear strain, the development of ductile shear zones embedded in strong wall rocks, and the transition from the strong to weak fault behaviors without invoking the presence of high fluid pressure or low friction coefficient metasomatic materials(e.g., smectite or lizardite) within the faults.

关键词： pseudotachylyte mylonite fault strength strain localization Indus-Tsangpo suture Tibet

In-situ Moissanite in Dunite: Deep Mantle Origin of Mantle Peridotite in Luobusa Ophiolite, Tibet

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 517-529页

作者： LIANG Fenghua xu zhiqin ZHAO Jianan State Key Laboratory of Continental Tectonics and Dynamics Institute of GeologyChinese Academy of Geological Sciences School of Earth Sciences and Resources China University of Geosciences

We report the discovery of an in-situ natural moissanite as an inclusion in the Cr-spinel from the dunite envelope of a chromitite deposit in Luobusa ophiolite,*** moissanite occurs as a twin crystal interpenetrated by two quadrilateral signal crystals with sizes of 17 pm × 10 μm and 20 μm × 7 μm,*** moissanite is green with parallel *** absorption peaks in its Raman spectra are at 967-971 cm-1,787-788 cm-1,and 766 *** absorption peaks in the infrared spectra are at 696 cm-1,767 cm-1,1450 cm-1,and 1551 cm-1,which are distinctly different from the peaks for synthetic silicon *** have been documented to form in ultra-high pressure,high temperature,and extremely low fO2 environments and their 13C-depleted compositions indicate a lower mantle *** with previous studies about other ultra-high pressure and highly reduced minerals in Luobusa ophiolite,the in-situ natural moissanite we found indicates a deep mantle origin of some materials in the mantle sequence of Luobusa ***,we proposed a transformation model to explain the transfer process of UHP materials from the deep mantle to ophiolite sequence and then to the supra-subduction zone *** between the crown of the mantle plume and mid-ocean ridge are suggested to be the dominant mechanism.

关键词： moissanite deep mantle origin mantle peridotite Luobusa ophiolite Tibet

Rock Damage Structure of the South Longmen-Shan Fault in the 2008 M8 Wenchuan Earthquake Viewed with Fault-Zone Trapped Waves and Scientific Drilling

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 444-467页

作者： LI Yonggang xu zhiqin LI Haibing State Key Laboratory of Continental Tectonic and Dynamics Institute of GeologyChinese Academy of Geological Science Department of Earth Sciences University of Southern California

This article is to review results from scientific drilling and fault-zone trapped waves （FZTWs） at the south Longman-Shan fault （LSF） zone that ruptured in the 2008 May 12 M8 Wenchuan earthquake in Sichuan,*** after the mainshock,two Wenchuan Fault Scientific Drilling （WFSD） boreholes were drilled at WFSD-1 and WFSD-2 sites approximately 400 m and 1 km west of the surface rupture along the Yinxiu-Beichuan fault （YBF）,the middle fault strand of the south LSF *** boreholes met the principal slip of Wenchuan earthquake along the YBF at depths of 589-m and 1230-m,*** slip is accompanied with a 100-200-m-wide zone consisting of fault gouge,breccia,cataclasite and *** to WFSD-1 site,the nearly-vertical slip of ～4.3-m with a 190-m wide zone of highly fractured rocks restricted to the hanging wall of the YBF was found at the ground surface after the Wenchuan earthquake.A dense linear seismic array was deployed across the surface rupture at this venue to record FZTWs generated by *** and 3-D finite-difference simulations of FZTWs recorded at this cross-fault array and network stations close to the YBF show a distinct low-velocity zone composed by severely damaged rocks along the south LSF at seismogenic *** zone is several hundred meters wide along the principal slip,within which seismic velocities are reduced by ～30-55％ from wall-rock velocities and with the maximum velocity reduction in the ～200-m-wide rupture core zone at shallow *** FZTW-inferred geometry and physical properties of the south LSF rupture zone at shallow depth are in general consistent with the results from petrological and structural analyses of cores and well log at WFSD *** interpret this remarkable low-velocity zone as being a break-down zone during dynamic rupture in the 2008 M8 *** examined the FZTWS generated by similar earthquakes before and after the 2008 mainshock and observed that seismic velocities

关键词： Rupture zone rock damage structure scientific drilling fault-zone trapped waves Wenchuan Earthquake Longmen-Shan Fault

Mineral inclusions in zircon domains and geological significance of SHRIMP U-Pb dating for coesite-bearing zircons of paragneiss in Sulu terrane, eastern China

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Science China Earth Sciences 2005年第2期48卷 175-184页

作者： LIU Fulai YANG Jingsui xu zhiqin Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China

Laser Raman spectroscopy and cathodoluminescence (CL) image reveal that zircons separated from paragneisses in the southwestern Sulu terrane (eastern China) preserve multi-stage mineral assemblages in different zircon domains. In the same paragneiss zircon sample, some zircon grains retain inherited (detrital) cores with abundant low-pressure mineral inclusions of Qtz + Phe + Ap + impurities and Qtz + Phe + impurities. The ultrahigh-pressure (UHP) metamorphic overgrowths mantles of these zircons preserve Coe, Coe + Phe and other UHP mineral inclusions, indicating that these inherited (detrital) zircons from protoliths experienced metamorphic recrystallization during the Sulu UHP metamorphic event. However, other zircon grains preserve UHP mineral inclusions of Coe, Coe + Ap and Coe + Phe in the cores and mantles, whereas the outmost rims contain quartz (Qtz) and other low-pressure mineral inclusions. These phenomena prove that the second group zircons were crystallized at UHP metamorphic stage and overprinted by the late retrogressive metamorphism related to the Sulu terrane exhumation. SHRIMP U-Pb dating reveals that zircons separated from the paragneisses recorded complicated geochronological traces. Some zircons retain inherited cores with the 206Pb/238U ages of 284-754 Ma, indicating the complexity of the detrital zircons in protoliths. Coesite-bearing zircon domains recorded 238-266 Ma (with the average age of 245(14 Ma) for the UHP metamorphic event. The retrogressive rims of zircons recorded 213-223 Ma (with the average age of 217(15 Ma) for the late-stage amphibolite facies metamorphic event, indicating that the rapid exhumation time for the Sulu UHP terrane is about 220 Ma.

关键词： Sulu terrane, paragneiss, zircon, mineral inclusion, cathodoluminescence, SHRIMP U-Pb dating.

伟晶岩结晶动力学和热力学及稀有金属超常富集成矿机制

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地质学报 2024年第5期98卷 1489-1506页

作者：左达昇杨可魏海珍王勤蒋少涌林和丰环淳许志琴南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室江苏南京210023 南京大学地球科学与工程学院大陆动力学研究院江苏南京210023 中国地质大学(武汉)紧缺战略矿产资源协同创新中心地质过程与矿产资源国家重点实验室资源学院湖北武汉430074

本文综述了伟晶岩结晶动力学、热力学和伟晶岩熔体稀有金属元素实现超常富集成矿的机制。结晶动力学涉及成核动力学和晶体生长动力学两个方面。低成核速率和高晶体生长速率是伟晶岩结晶动力学的重要特征,在结晶过程受到水、助溶剂以及... 详细信息

本文综述了伟晶岩结晶动力学、热力学和伟晶岩熔体稀有金属元素实现超常富集成矿的机制。结晶动力学涉及成核动力学和晶体生长动力学两个方面。低成核速率和高晶体生长速率是伟晶岩结晶动力学的重要特征,在结晶过程受到水、助溶剂以及过冷条件三个因素共同制约。伟晶岩熔体的相态(超临界态)可能在伟晶岩形成和稀有金属元素超常富集中扮演重要角色。花岗伟晶岩稀有金属超常富集程度受到岩浆源区成分、岩浆结晶分异过程与熔体化学成分等因素的控制。花岗质岩浆高度分异结晶或者变质沉积岩部分熔融直接形成的成矿伟晶岩熔体均需要源岩中稀有金属元素预富集。深熔作用产生的低程度、小体积的伟晶岩熔体具有更高的稀有金属元素成矿潜力。在岩浆分异演化过程中,稀有金属元素的超常富集主要通过超临界熔体/流体、岩浆熔体作用、过冷作用实现。超临界熔体/流体发生熔体-流体不混溶作用使稀有金属元素在熔体相和流体相间再分配和富集;岩浆熔离作用使稀有金属元素选择性分配到富挥发分的熔体中,导致稀有金属元素再次富集;过冷作用降低稀有金属矿物结晶的饱和浓度,促进稀有金属矿物结晶。熔体的化学成分(如挥发分)直接影响熔体的物理、化学性质。例如,挥发分的富集能够降低熔体黏度,促进岩浆分异结晶过程。挥发分和稀有金属元素的亲和性也控制稀有金属元素在不同相熔体中的分配和富集,显著增加稀有金属元素的溶解度和迁移富集能力,有助于伟晶岩中稀有金属超常富集和成矿。

关键词：伟晶岩结晶动力学结晶热力学稀有金属元素超常富集成矿

一种面向丁羟推进剂燃速预测的机器学习融合模型

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固体火箭技术 2024年第5期47卷 738-744页

作者：孙娜林可仁沈坚王心怡许志钦张斌上海航天动力技术研究所上海201109 北京航空航天大学北京100191 上海交通大学上海200240

建立了以端羟基聚丁二烯(HTPB)推进剂原材料参数和组分含量为输入变量、燃速值为输出的机器学习预测模型。首先,通过经验性单因素规律对包括随机森林回归、支持向量回归、高斯过程回归、核岭回归和径向基函数模型等进行了初筛;然后,以... 详细信息

建立了以端羟基聚丁二烯(HTPB)推进剂原材料参数和组分含量为输入变量、燃速值为输出的机器学习预测模型。首先,通过经验性单因素规律对包括随机森林回归、支持向量回归、高斯过程回归、核岭回归和径向基函数模型等进行了初筛;然后,以最大绝对误差(AE_(max))、最大相对误差(RE_(max))、均方根误差(RMSE)及平均绝对误差(MAE)作为模型的性能评价指标,对不同模型的预测性能进行对比,筛选出最大相对误差RE_(max)<5%的模型,对通过筛选的模型进行融合获得最终的燃速预测模型,并将融合模型与单一模型的预测性能进行对比;最后,利用样本集外的10组数据对融合模型的预测精度进行了验证。结果表明,融合模型的RE_(max)和RMSE小于任何单一模型,其中AE_(max)=0.68、RE_(max)=3.97%、RMSE=0.3214、MAE=0.253,可实现对此类HTPB推进剂燃速的高精度、高效率预测。

关键词： HTPB推进剂燃速预测机器学习多模型融合

Indosinian Orogenesis in the Lhasa Terrane, Tibet: New Muscovite ^(40)Ar-^(39)Ar Geochronology and Evolutionary Process

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1116-1127页

作者： LI Huaqi xu zhiqin YANG Jingsui TANG Zhemin Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

Muscovite 40 Ar-39 Ar dating of muscovite-quartz schist, eclogite and retrograde eclogite indicates an Indosinian orogenesis occurred at 220-240 Ma in the Lhasa terrane, which is caused by the closure of Paleo-Tethyan ocean basin and the following collision of the northern Lhasa terrane and southern Gondwana land. This Indosinian orogenesis is further confirmed by the regional sedimentary characteristics, magmatic activity and ophiolite mélange. This evidence suggests that the Indosinian orogenic belt in the Lhasa terrane is widely distributed from the Coqen county in the west, and then extends eastward through the Ningzhong and Sumdo area, finally turning around the eastern Himalayan syntaxis into the Bomi county. Based on the evolutionary process, the geological development of Lhasa terrane from early Paleozoic to early Mesozoic can be divided into seven stages. All of the seven stages make up a whole Wilson circle and reveal a perfect evolutionary process of the Paleo-Tethys ocean between the northern Lhasa terrane and southern Gondwana land. The Indosinian orogenisis is a significant event for the evolution of the Lhasa terrane as well as the Tibetan Plateau.

关键词： 40 Ar-39 Ar geochronology Lhasa terrane Indosinian orogenesis Tibet