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关键词： 教学案例   教育管理   性质   价值   发展趋势  

摘要： 专业学位研究生教育不能只重视理论知识的学习,还应进一步培养学生处理实践问题的能力.由于案例所特有的真实性、教学性、叙事性和学理性,对于改进教育专业学位研究生培养模式有着深远价值.作为沟通教育理论与实践的桥梁,案例集中体现了知识的建构性、社会性和情境性,是教育工作者反思教学实践、总结教学经验的重要载体,也是提升专业学位研究生培养质量的重要途径.然而,随着教学案例的推广和应用,其自身也存在一些问题有待优化,如案例分布上学科间比例不均、案例编排上指导手册质量不高、案例价值上学理性不足、案例应用上教学效果不佳等.

关键词： asymptotic property   endogenous spatial weight matrix   heterogeneity   high-dimensional spatial dependence data   quantile regression  

摘要： With the development of big data technology, the dimensionality of spatial data is becoming higher and higher, and the endogeneity and heterogeneity of data often exist simultaneously. In this paper, we propose a quantile regression model of high-dimensional spatial dependent data with endogenous spatial weight matrix so as to analyze high-dimensional spatial dependent data robustly. We then develop a three-step penalized quantile estimation procedure through combining the instrumental variable method, variable selection method with robust statistic method, and establish the consistency and the asymptotic normality of the corresponding estimators. In addition, the oracle theoretical properties of variable selection are derived under some mild conditions. At last, we investigate the effectiveness and robustness of the proposed model and method through simulations and an application to housing prices in 284 prefecture-level cities across the country. © 2025 Chinese Academy of Sciences. All rights reserved.

关键词： Southeastern Tibetan Plateau   Heavy precipitation   Atmospheric circulation patterns   Tibetan Plateau vortex type   Mid-latitude trough type  

摘要： The southeastern Tibetan Plateau (SETP) is the preeminent summer heavy precipitation region within the Tibetan Plateau (TP). However, the large-scale circulation types and dynamics driving summer heavy precipitation in the SETP remain inadequately elucidated. Using the hierarchical clustering method, two distinctive atmospheric circulation patterns associated with heavy precipitation were identified: the Tibetan Plateau vortex type (TPVT, constituting 56.6% of the events) and the mid-latitude trough type (MLTT, 43.4%). A comprehensive examination of the two atmospheric circulation patterns reveals a clear nexus between the occurrences of summer heavy precipitation and positive vorticity anomalies, moisture convergence, as well as the southeastward displacement of the westerly jet core. Specifically, TPVT events are characterized by the eastward and dry-to-wet potential vorticity progression processes, while MLTT events are linked to the intrusion of a deep extratropical trough into the SETP. This study advances our understanding of the complex mechanisms governing the summer heavy precipitation in the SETP, shedding light on critical meteorological processes in the region. (c) 2024 Science China Press. Published by Elsevier B.V. and Science China Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： inflammation   mortality   prevention  

摘要： Cardiovascular disease(CVD)remains a major cause of death and rising health care costs worldwide[1].Hyperlipidemia is an important,modifiable risk factor for CVD[2].Consequently,prevention and treatment of CVD have emphasized targeting low-density lipoprotein cholesterol(LDL-C)[3].However,despite the efficiency of statins to reduce LDL-C concentration,the risk of recurrent cardiovascular events and mortality remains[4].Systemic inflammation has emerged as an important source of residual cardiovascular risk among patients receiving statin therapy[4].These contemporary data support the use of inflammation-inhibiting interventions as an effective strategy to further reduce cardiovascular *** is a highly modifiable lifestyle factor that has been shown to play a role in the regulation of systemic inflammation[5].Previous studies revealed that a higher dietary inflammatory potential was associated with an increased incidence of CVD and mortality in the general population[6].However,it is unclear whether this association persists in patients at-risk of or with established CVD who are already being treated with statins,a therapy whose mode of action includes decreasing inflammation[7].Evaluating the potential for residual risk due to diet is critical considering the large role inflammation plays in cardiovascular diseases.

关键词： 陈猜想   高度函数   Simons型积分  

摘要： 本文研究了球空间中具有常第二基本形式模长平方S超曲面的陈猜想.目前"S的第三个间隙点取值是否为2n"依然是一个公开性的问题.首先我们研究了位置向量和法向量在自然坐标向量上的高度函数及其性质,然后证明了在超曲面上存在同时具有S第一、二、三间隙点项的Simons型积分方程,这些结果可以为解决陈猜想的研究提供全新的思考途径与求解方法.

摘要： The 8 April 2024 total solar eclipse (TSE) provides a unique opportunity to study the solar corona. This work presents our prediction of the solar corona at the time of the eclipse based on magnetohydrodynamic (MHD) modeling performed with the Alfvén Wave Solar Model-Realtime (AWSoM-R) in the Space Weather Modeling Framework, developed at the University of Michigan. We performed multiple simulations made with data input in the form of synchronic magnetograms from four sources, i.e., ADAPT-GONG, Lockheed Martin ESFAM, HipFT and NSO-NRT magnetograms. Simulations also include a higher-resolution model and a post-eclipse model incorporating newly emerged active regions. Our study fundamentally focuses on the limitations imposed by the lack of global solar observations, particularly on how these limitations affect coronal simulations. Specifically, we examine how differences among the magnetograms and the absence of observations from the east limb, due to the Sun's rotation, impact the accuracy of the predicted coronal structures. We synthesized a variety of representative observables, including the white-light and extreme-ultraviolet images from each model, and compared them with observations. The synthesized observables show remarkable differences because of the distinct magnetic coronal topologies, which stem from the varied magnetic flux distributions and the gaps in observational coverage. Our findings emphasize the need for comprehensive and multi-satellite magnetic field observations to improve future solar corona predictions.