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高质量教师的供给迟疑:来自“双一流”建设高校毕业生和在校生的双重数据验证

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教师教育研究 2024年第3期36卷 68-77页

作者：张新亮石艳王娜章则名南京师范大学教育科学学院江苏南京210097 东北师范大学教育学部吉林长春130024 东北师范大学学生就业指导服务中心吉林长春130024 上海海洋大学研究生院上海201306

高质量教师的需求需要高质量教师的供给,但作为高质量教师的供给侧,高水平师范院校本科生从教意愿不高和从教行为推迟的就业迟疑现象,暂未引起国内研究者的足够关注。基于一所“双一流”建设高校的毕业生行政数据和在校生调查数据,研究... 详细信息

高质量教师的需求需要高质量教师的供给,但作为高质量教师的供给侧,高水平师范院校本科生从教意愿不高和从教行为推迟的就业迟疑现象,暂未引起国内研究者的足够关注。基于一所“双一流”建设高校的毕业生行政数据和在校生调查数据,研究使用固定效应模型描述了本科生从教意愿和行为的相关特征。研究发现,男性、学术能力强、来自经济和社会发展水平较高地区的个体,毕业后推迟进入教师行业的可能性更高。外向型人格、职业认同感和教育信念强烈、参与支教活动的在校生,选择进入教师行业的意愿更高。关注并解决高质量教师的就业迟疑现象一方面要提高教师教育政策的精准性,另一方面要强化高水平师范院校职前培养的职业认同和实践能力。

关键词：职业选择教师职业师范院校学业表现

东喜马拉雅构造结高压基性麻粒岩成因与构造意义

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地质学报 2024年第1期98卷 96-115页

作者：吴双鹏张泽明田作林芦维瑞郭明明张成圆中国地质大学(北京) 北京100083 中国地质科学院地质研究所北京100037

东喜马拉雅构造结南迦巴瓦杂岩中存在典型的泥质、长英质和基性高压麻粒岩。但是,高压麻粒岩在南迦巴瓦杂岩中的分布范围、变质条件和变质时间是否存在空间上的变化并不明确。本文对南迦巴瓦杂岩西南部巴嘎地区的高压基性麻粒岩进行了... 详细信息

东喜马拉雅构造结南迦巴瓦杂岩中存在典型的泥质、长英质和基性高压麻粒岩。但是,高压麻粒岩在南迦巴瓦杂岩中的分布范围、变质条件和变质时间是否存在空间上的变化并不明确。本文对南迦巴瓦杂岩西南部巴嘎地区的高压基性麻粒岩进行了岩石学和年代学研究。研究表明,巴嘎高压基性麻粒岩由石榴子石、单斜辉石、角闪石、斜长石、黑云母和石英组成,石榴子石变斑晶发育生长成分环带。识别出三期矿物组合:进变质矿物组合M1为石榴子石变斑晶核部及其矿物包裹体,包括石榴子石、石英、榍石和磷灰石;峰期矿物组合M2为变斑晶石榴子石边部和基质矿物,即石榴子石+单斜辉石+斜长石+角闪石+石英+金红石+熔体;退变质矿物组合M3呈冠状体或基质产出,其组合为角闪石+斜长石+单斜辉石+黑云母+石英+榍石。高压基性麻粒岩的峰期变质条件约为1.5 GPa和915℃,具有顺时针P-T轨迹,退变质的早期和晚期分别为近等温降压和降温降压过程。高压基性麻粒岩在峰期条件下发生了明显的部分熔融,含~26%(体积)的熔体,其退变质和熔体结晶作用很可能发生在26~14 Ma。本文和研究区现有研究成果表明,东喜马拉雅构造结南迦巴瓦杂岩中的高压麻粒岩广泛分布,从东北部的加拉、直白和派乡延伸到西南部的巴嘎沟,形成了一条长度超过80 km的高压麻粒岩带。整个带中的高压麻粒岩具有类似的变质条件和持续时间,是印度大陆地壳平缓俯冲并经历了高温和高压变质与部分熔融的产物,构成了喜马拉雅造山带的加厚下地壳。大量高压麻粒岩强烈部分熔融产生的熔体可能为喜马拉雅淡色花岗岩提供了源区。

关键词：高压基性麻粒岩 P-T-t轨迹部分熔融南迦巴瓦杂岩东喜马拉雅构造结

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面波非大圆路径传播研究进展

地球物理学进展 2024年第3期39卷 990-1002页

作者：范芮芮张泽铭叶庆东陈浩朋广东工业大学土木与交通工程学院测绘工程系广州510006 中国地震局第一监测中心天津300180

传统面波层析成像多基于射线理论,并假定面波沿大圆路径传播.由于地球介质的横向非均匀性,面波有时会偏离大圆路径传播,引起面波入射方位角异常和多路径传播效应.本文通过总结面波非大圆路径传播的研究成果,分析了面波非大圆路径传播的... 详细信息

传统面波层析成像多基于射线理论,并假定面波沿大圆路径传播.由于地球介质的横向非均匀性,面波有时会偏离大圆路径传播,引起面波入射方位角异常和多路径传播效应.本文通过总结面波非大圆路径传播的研究成果,分析了面波非大圆路径传播的主要特点及成因:面波非大圆路径传播效应随着周期的减小而增强,在短周期的非大圆路径传播效应非常明显,地壳上地幔结构的横向非均匀性是导致面波偏离大圆路径传播的主要因素.接着,介绍了测量面波入射方位角异常的两类方法——单台三分量偏振分析和台阵分析方法,其中台阵分析方法相对于单台三分量偏振分析更为可靠和稳定.讨论了面波非大圆路径传播对于面波频散测量和面波层析成像的影响.由于面波的非大圆路径传播,采用天然地震双台法测量的面波频散会高于真实值,而利用背景噪声测量的双台频散会低于真实值.因此,基于大圆路径假设的面波层析成像结果会与真实值出现偏差,特别是各向异性快波方向可能受到的影响更大.最后,本文对面波非大圆路径传播的研究方向进行了展望:在天然地震面波层析成像中,可以利用面波入射方位角异常改正双台面波相速度测量,然后再进行面波层析成像;利用谱元法模拟地震波是研究面波非大圆路径传播的一种有效手段,既需要考虑全球大尺度地壳上地幔结构,也需要考虑研究区内部精细三维结构对于面波非大圆传播的影响.

关键词：面波层析成像非大圆路径传播聚束分析入射方位角异常多路径效应

Phase equilibrium modeling of zircon stability in mantle peridotite:Implication for crust-mantle interaction

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Science China Earth Sciences 2022年第2期65卷 282-298页

作者： Hua XIANG Jianping ZHENG Yibing LI zeming zhang Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of Earth Sciences State Key Laboratory of Geological Processes and Mineral ResourcesChina University of GeosciencesWuhan 430074China

Zircon is a common accessory mineral in various rocks,especially in the crustal *** is the best mineral for U-Pb ***,trace elements and isotopes of the mineral can also provide much information concerning the formation and evolution of *** are a growing number of reports of zircon existing in mantle ***,it is generally considered that zircon is unlikely crystallized in ultrabasic rocks due to SiO_(2)-*** this paper,the SiO_(2) activity and zircon/baddeleyite transition curve at different conditions were calculated through thermodynamic phase equilibrium modeling,to reveal the main factors affecting the SiO_(2) activity and the stability of zircon/baddeleyite in ultrabasic and basic rocks,especially in mantle *** results provide a thermodynamic basis for interpreting the genesis and significance of zircon in mantle *** is,the SiO_(2) activity is mainly controlled by stable mineral assemblages and temperature-pressure *** orthopyroxene+olivine assemblage in peridotite as an effective buffer restricts the SiO_(2) activity in a relatively high range with a small *** upper temperature limit of zircon can reach more than 1500℃ with this mineral *** the low-temperature serpentinization of peridotite,the replacement of olivine and pyroxene by serpentine can result in a significant decrease of SiO_(2) activity,and baddeleyite can be stabilized at<530℃ and<2.7 *** peridotite is strongly metasomatized by the SiO_(2)-bearing fluid,the addition of SiO_(2) can increase its activity and make zircon stable at low *** SiO_(2) activity in ultrabasic-basic rocks is not only positively correlated with the SiO_(2) content but also negatively correlated with the Ca and Na contents of *** is because Ca and Na preferentially combine with Si and Al to form Si-rich minerals,such as clinopyroxene and *** process will consume excessive SiO_(2),decreasing

关键词： Zircon Baddeleyite Phase equilibrium modeling Mantle peridotite Ultrabasic rock

The compositional zoning of garnet in eclogite from western segment of Altyn Tagh, northwestern China and its dynamic significance

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Chinese Science Bulletin 2000年第1期45卷 79-83页

作者： zhang zeming YANG Yong zhang Jianxin Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Analyses and Test Center China University of Geosciences(Wuhan)Wuhan 430074China

The eclogites from the Altyn Tagh, northwestern China have been subjected to medium-temperature and high-pressure metamorphism, and then overprinted by the amphibolite to granulite facies retrograde metamorphism, A complex compositionai zoning was well preserved in the garnet porphyroblast formed during the metamorphism of eclogite facies. This zoning recorded P-T path of multistage metamorphism, and an early retrogressive process with features of decreasing pressure and increasing temperature. This evidences a short residence time for the eclogite at peak metamorphism and early retrogression, and thus rapid tectonic uplift history.

关键词： eclogite garnet growth zoning P-7 path exhumation rate Altyn Tagh.

The ages of U-Pb and Sm-Nd for eclogite from the western segment of Altyn Tagh tectonic belt——Evidence for existence of Caledonian orogenic root

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Chinese Science Bulletin 1999年第24期44卷 2256-2259页

作者： Jianxin zhang zeming zhang Zhiqin Xu Jingsui Yang Junwen Cui Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

The eclogites of Altyn Tagh tectonic belt occur as lens within gneisses characterized by amphibolite-facies mineral parageneses. The well-preserved eclogite is selected for Sm-Nd and U-Pb isotopic dating. The Sm-Nd isotopic data yield a whole rock-garnet-omphacite isochron of (500 ?10) Ma. The U-Pb isotopic measurements of zircons show that the four

关键词： Altyn Tagh tectonic belt eclogite Sm-Nd dating U-Pb dating.

Metamorphic P-T-t Path of UHT Granulites from the North Tongbai Orogen, Central China

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Journal of Earth Science 2018年第5期29卷 1116-1131页

作者： Hua Xiang zeming zhang Liming Zhao Zengqiu Zhong Hanwen Zhou Key Laboratory of Deep-Earth Dynamics Institute of Geology Chinese Academy of Geological Sciences School of Earth Sciences and Resources China University of Geosciences School of Earth Sciences China University of Geosciences

Although zircon U-Pb geochronometer has been widely used for dating metamorphism in moderate- to high-grade metamorphic rocks, it is still difficult to link the zircon U-Pb age to pressure and temperature （P-T） conditions. In this study, zircon trace elements and Hf isotopes and REE partitioning between zircon and garnet are adopted to track the formation condition of zircon in the granu- lites from North Tongbai Orogen, Central China. Combined with previous metamorphic P-T path results, a quantitative integrated anticlockwise P-T-t path was established for Tongbai granulites. These grauulites recorded an early low-P heating followed by a dramatic pressure increase. Evidence for the prograde history （M1） is provided by cordierite, orthopyroxene and biotite inclusions in garnet. The prograde metamorphism occurred at around 443±3 Ma, with P-T conditions of ca. 730-820 ℃ and 〈6 kbar. The peak metamorphic （M2） condition is 〉920 ℃ and 8.5-10 kbar and the peak metamorphism age is ca. 432±4 Ma. At around 419 Ma, the granulites suffered an amphibolite-facies retrograde metamorphism （M3）, represented by the replacement of garnet by biotite and plagioclase, and clinopyroxene by amphibole, with metamorphic condition of ca. 700℃ and ca. 7 kbar. The last retrograde metamorphism （M4） is a greenschist-facies overprint with an age of ca. 404 Ma. It is concluded that the meta- morphism of Tongbai granulite lasted for more than 40 Ma, including a stage of more than 20 Ma granulitc-facies metamorphism. The prolonged granulite-facies metamorphism resulted from the continuous northward subduction of the Shangdan oceanic crust beneath the North Qinling terrane.

关键词： granulites zircon U-Pb dating P-T-t path trace element Ln-Hf isotope Tongbai Orogen.

Orbital Interception Pursuit Strategy for Random Evasion Using Deep Reinforcement Learning

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Space(Science & Technology) 2023年第1期3卷 606-619页

作者： Rui Jiang Dong Ye Yan Xiao Zhaowei Sun zeming zhang Research Center of Satellite Technology School of AstronauticsHarbin Institute of TechnologyHarbinChina Space Missions Engineering Lab Department of Aerospace Science and TechnologyPolitecnico di MilanoMilanoItaly

Aiming at the interception problem of noncooperative evader spacecraft adopting random maneuver strategy in one-to-one orbital pursuit-evasion problem,an interception strategy with decision-making training mechanism for the pursuer based on deep reinforcement learning is *** core purpose is to improve the success rate of interception in the environment with high *** of all,a multi-impulse orbit transfer model of pursuer and evader is established,and a modular deep reinforcement learning training method is ***,an effective reward mechanism is proposed to train the pursuer to choose the impulse direction and impulse interval of the orbit transfer and to learn the successful interception strategy with the optimal fuel and ***,with the evader taking a random maneuver decision in each episode of training,the trained decision-making strategy is applied to the pursuer,the corresponding interception success rate of which is further *** results show that the pursuer trained can obtain universal and variable interception *** each round of pursuit-evasion,with random maneuver strategy of the evader,the pursuer can adopt similar optimal decisions to deal with high-dimensional environments and thoroughly random state space,maintaining high interception success rate.

关键词： pursuit mechanism thoroughly

Lnc CPS1-IT1靶向调控内皮-间质转化抑制OSA所致肺动脉高压的机制

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国际呼吸杂志 2024年第9期44卷 1012-1022页

作者：魏丽陈昊王秋波张泽明上海健康医学院附属周浦医院呼吸内科上海

目的探讨在低氧环境下, 长链非编码RNA CPS1内含子转录本1(Lnc CPS1-IT1)通过影响内皮-间质转化(EndoMT)治疗阻塞性睡眠呼吸暂停(OSA)所致肺动脉高压(PH)的分子调控机制。方法本研究为实验研究。以人脐静脉内皮细胞构建OSA的细胞模型, ... 详细信息

目的探讨在低氧环境下, 长链非编码RNA CPS1内含子转录本1(Lnc CPS1-IT1)通过影响内皮-间质转化(EndoMT)治疗阻塞性睡眠呼吸暂停(OSA)所致肺动脉高压(PH)的分子调控机制。方法本研究为实验研究。以人脐静脉内皮细胞构建OSA的细胞模型, 并使用该模型分别构建空白对照组, 空过表达载体组(阴性对照过表达载体), 长链非编码RNA CPS1内含子转录本1(Lnc CPS1-IT1)过表达组(Lnc CPS1-IT1过表达载体), 空沉默载体组(阴性对照沉默载体), 沉默Lnc CPS1-IT1组(沉默Lnc CPS1-IT1的短发夹RNA);使用吡咯烷二硫代甲酸铵(PDTC)阻断细胞核因子κB(NF-κB)信号通路构建Lnc CPS1-IT1过表达+PDTC组。比较空过表达载体组与Lnc CPS1-IT1过表达组, 空沉默载体组与沉默Lnc CPS1-IT1组EndoMT相关分子标志物[血小板-内皮细胞黏附分子(CD31)、α-平滑肌肌动蛋白(α-SMA)、锌指转录因子(SNAIL)]和胶原蛋白(Ⅰ型胶原、Ⅲ型胶原)mRNA、蛋白表达, 以及促炎细胞因子[肿瘤坏死因子α(TNF-α)、白细胞介素(IL)-10、IL-13]的水平。通过Transwell测定法检测Lnc CPS1-IT1对于细胞迁移能力的影响。RNA免疫沉淀和荧光素酶报告基因法检测Lnc CPS1-IT1和缺氧诱导因子1α(HIF-1α)的结合情况。比较PDTC处理前后EndoMT相关分子标志物和胶原蛋白mRNA、蛋白表达, 以及促炎细胞因子的水平。结果 Lnc CPS1-IT1过表达组CD31 mRNA和蛋白表达均较空过表达载体组升高, α-SMA、SNAIL、Ⅰ型胶原和Ⅲ型胶原的mRNA和蛋白表达均较空过表达载体组降低, 差异均有统计学意义(均P<0.001)。沉默Lnc CPS1-IT1组中CD31 mRNA和蛋白表达均较空沉默载体组降低, α-SMA、SNAIL、Ⅰ型胶原和Ⅲ型胶原的mRNA和蛋白表达均较空沉默载体组升高, 差异均有统计学意义(均P<0.001)。Lnc CPS1-IT1过表达组TNF-α、IL-10、IL-13的水平均较空白过表达载体组降低, 沉默Lnc CPS1-IT1组TNF-α、IL-10、IL-13的水平均较空白沉默载体组升高, 差异均有统计学意义(均P<0.001)。与空白对照组(49.33±2.52)相比, Lnc CPS1-IT1过表达组细胞迁移数量减少(30.00±2.65), 而沉默Lnc CPS1-IT1组细胞迁移数量增多(82.00±4.00), 差异均有统计学意义(均P<0.001)。RNA免疫沉淀结果显示, Lnc CPS1-IT1与HIF-1α的结合较免疫球蛋白G增加, 差异有统计学意义[(4.22±0.03)比(0.99±0.02), t=163.50, P<0.001]。荧光素酶报告基因法检测结果显示, Lnc CPS1-IT1与HIF-1α结合后的荧光强度下降[(120.33±2.83)比(24.33±2.12)], 差异有统计学意义(t=43.42, P<0.001)。Lnc CPS1-IT1过表达+PDTC组CD31 mRNA和蛋白质较Lnc CPS1-IT1过表达组升高, α-SMA、SNAIL、Ⅰ型胶原和Ⅲ型胶原的mRNA和蛋白质均较Lnc CPS1-IT1过表达组降低, 差异均有统计学意义(均P<0.001)。Lnc CPS1-IT1过表达+PDTC组TNF-α、IL-10、IL-13水平均较Lnc CPS1-IT1过表达组下降(均P<0.05)。结论 Lnc CPS1-IT1可以通过抑制HIF-1α的转录活性影响NF-κB通路, 降低炎症因子的释放, 靶向调控EndoMT, 从而抑制OSA所致PH。

关键词：睡眠呼吸暂停, 阻塞性高血压, 肺性 RNA, 长链非编码 NF-κB 缺氧诱导因子1, α亚基 CPS内含子转录本1 内皮-间质转化