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OPTIMAL ALLOCATION FOR ESTIMATING THE CORRELATION COEFFICIENT OF MORGENSTERN TYPE BIVARIATE EXPONENTIAL DISTRIBUTION BY RANKED SET SAMPLING WITH CONCOMITANT VARIABLE

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Journal of Systems Science & Complexity 2013年第2期26卷 249-260页

作者： XIE Minyu XIONG ming WU ming School of Mathematics and Statistics Central China Normal University

Ranked set sample is applicable whenever ranking of a set of sample units can be done easily by a judgement method of the study variable or of the auxiliary variable. This paper considers ranked set sample based on the auxiliary variable X which is correlated with the study variable Y, where （X, Y） follows Morgenstern type bivariate exponential distribution. The authors discuss the optional allocation for unbiased estimators of the correlation coefficient p of the random variables X and Y when the auxiliary variable X is used for ranking the sample units and the study variable Y is measured for estimating the correlation coefficient. This paper first gives a class of unbiased estimators of p when the mean 0 of the study variable Y is known and obtains an essentially complete subclass of this class. Further, the optimal allocation of the unbiased estimators is found in this subclass and is proved to be Bayes, admissible, and minimax. Finally, the unbiased estimator of p under the optimal allocation in the case of known θ is reformed for estimating p in the case of unknown θ, and the reformed estimator is shown to be strongly consistent.

关键词： Concomitants of order statistic Morgenstern type bivariate exponential distribution optimal allocation ranked set sample unbiased estimator.

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“冷盆”缫丝技术与阆中源考

丝绸 2025年第1期62卷 94-100页

作者：刘凯旋陈祥平程明四川省丝绸科学研究院成都610031 四川省丝绸协会成都610031

四川省阆中市出土的“缫丝图铜摆件”被专家鉴定为宋代铸造,其展现的煮、缫分离的“冷盆”缫丝技术,乃现代缫丝工业技术之雏形,对于蚕丝品质的提升具有里程碑的意义。而现已出版的中国丝绸史书籍中将“冷盆”缫丝技术划归元代加以描述... 详细信息

四川省阆中市出土的“缫丝图铜摆件”被专家鉴定为宋代铸造,其展现的煮、缫分离的“冷盆”缫丝技术,乃现代缫丝工业技术之雏形,对于蚕丝品质的提升具有里程碑的意义。而现已出版的中国丝绸史书籍中将“冷盆”缫丝技术划归元代加以描述。文章对宋代前后缫车及缫丝工艺技术演变过程进行历史追溯和研究,对阆中从宋代至民国与“冷盆”缫丝相关的历史脉络进行梳理,以探究“冷盆”缫丝技术的渊源。研究表明,“冷盆”缫丝技术源于宋代,而“缫丝图铜摆件”所呈现的煮、缫分离的缫丝生产场景,与现有文献典籍及图考中所载“冷盆”缫丝高度契合,且三者互为映射,从而印证了阆中(古阆州)为宋代“冷盆”缫丝技术源流地。

关键词：宋代缫丝图铜摆件缫丝技术阆中冷盆缫丝源流地

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Machining of SiC ceramic matrix composites:A review

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Chinese Journal of Aeronautics 2021年第4期34卷 540-567页

作者： Qinglong AN Jie CHEN Weiwei ming ming CHEN State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Continuous fiber reinforced SiC ceramic matrix composites(FRCMCs-SiC)are currently the preferred material for hot section components,safety–critical components and braking components(in the aerospace,energy,transportation)with high value,and have triggered the demand for ***,the high brittleness,anisotropy,and heterogeneity of materials bring great challenges to machining,due to high mechanical and thermal loads,severe tool wear,and poor machining *** the increasing demand of FRCMCs-SiC parts,high-quality and high-efficient machining has become a hot *** review paper provides a detailed literature survey on the machining of *** material removal mechanism,defect form,and interfacial mechanical properties of FRCMCs-SiC were *** machining processes of FRCMCs-SiC were introduced,and their respective advantages and disadvantages were *** the low machinability(high hardness,high brittleness,anisotropy,and heterogeneity)of FRCMCs-SiC,preliminary experiments have proved that ultrasonic-assisted machining and laser-assisted machining have shown unique advantages in reducing force and tool wear,improving machining quality and machining *** machined surface integrity was discussed,the influence of process parameters on the machined surface quality was analyzed,and the machining defects of FRCMCs-SiC were *** for FRCMCs-SiC,the existing quantitative evaluation of the machined surface integrity was weak and unsystematic.

关键词： Ceramic matrix composites Machining Material removal mechanisms Quality Surface integrity

Interpretation of gas-film cooling against aero-thermal heating for high-speed vehicles

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Applied Mathematics and Mechanics(English Edition) 2016年第12期37卷 1615-1630页

作者： ming DONG Department of Mechanics Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072China

The possible application of the film-cooling technique against aero-thermal heating for surfaces of high-speed flying vehicles is discussed. The technique has been widely used in the heat protection of gas turbine blades. It is shown in this paper that, by applying this technique to high-speed flying vehicles, the working principle is fundamentally different. Numerical simulations for two model problems axe performed to support the argument. Besides the heat protection, the appreciable drag reduction is found to be another favorable effect. For the second model problem, i.e., the gas cooling for an optical window on a sphere cone, the hydrodynamic instability of the film is studied by the linear stability analysis to observe possible occurrence of laminar-turbulent transition.

关键词： film cooling aero-thermal heating numerical simulation laminar-turbulenttransition linear stability analysis

Circulation background of climate patterns in the past millennium: Uncertainty analysis and re-reconstruction of ENSO-like state

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Science China Earth Sciences 2016年第6期59卷 1225-1241页

作者： TAN ming Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences

The question of whether or not global warming has paused since more than ten years ago, namely ＂warming hia- tus＂, has attracted the attention of climate science community including the IPCC. Some authors have attributed the ＂warming hiatus＂ to the internal changes in the climate system, i.e., the recombination of ocean-atmosphere circulations. Therefore, it is necessary to propose higher requirements on reconstructing circulation background of climate change for the past millennium. However, the analyses of changes in atmospheric circulation over the last millennium as well as the conclusions of related re- gional climate patterns are so widely different and contradictory, bringing uncertainties to our understanding of regional even global climate change to a great extent. On the other hand, in the last 10 years the high-precision U/Th-dated stalagmite oxygen isotope ratio （δ^18O） sequences provided an accurate chronological frame for the paleoclimate study of the middle and late Pleistocene, in which all authors from China took the Chinese stalagmite δ^18O as the summer monsoon index without excep- tion. However, this point of view misleads the climate scientists into thinking that the stalagmite δ^18O can be as the proxy of precipitation amount. Nevertheless, it is well known that all of these records have a lot in common in the low frequency trend. However, most sequences cannot be calibrated by instrumental precipitation records, and thus the uncertainty of the climate research framework of China and even of the world has increased. Therefore, it is imperative for climatology to clarify the origin of contradiction and to reduce the uncertainty as early as possible. On the basis of analyzing the significance of stalag- mite ~180 in the monsoon regions of China, the author tries to propose a new circulation proxy in this paper： integrating the Chinese stalagmite oxygen isotope sequence to reconstruct the tropical Pacific sea surface temperature gradient, i.e., th

关键词： The past millennium ENSO Circulation background Climate pattern WPSH Stalagmite δ^18O Circulation recombination

circT P63-N suppresses the proliferation and metastasis of nasopharyngeal carcinoma via engaging with HSP90AB1 to modulate the YAP1/Hippo signaling pathway

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Science China Life Sciences 2025年

作者： Dan Wang Sicheng Zuo Junshang Ge Hongke Qu Jie Wu Na Yi Lei Shi Yumin Wang Yongzhen Mo Chunmei Fan Yi He Pan Chen ming Zhou Bo Xiang Wei Xiong Wenjia Guo Zhaoyang Zeng Can Guo NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine Central South University Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education Cancer Research Institute and School of Basic Medicine Sciences Central South University Furong Laboratory Cancer Research Institute Affiliated Cancer Hospital of Xinjiang Medical University Xinjiang Key Laboratory of Translational Biomedical Engineering

Circular RNAs(circRNAs) play pivotal roles in the development and progression of various diseases, including malignant tumors. However,the biological functions and the underlying mechanisms of many circRNAs remain elusive. In this study, we identified a novel circRNA,circTP63-N, generated through the splicing of exons 2–4 of the TP63 gene in nasopharyngeal carcinoma(NPC). circTP63-N was found to be downregulated in clinical samples of NPC. Both in vitro and in vivo experiments unequivocally demonstrated that circTP63-N inhibits the proliferation and metastasis of NPC cells. Further investigations revealed that circTP63-N interacted with the HSP90AB1 protein, leading to the recruitment of LATS/YAP1 proteins. This, in turn, induced phosphorylation and ubiquitination-dependent degradation of YAP1, resulting in reduced nuclear translocation of YAP1 and inhibition of the transcriptional activation of downstream oncogenic genes, including INHBA, MMP3, and CCNE2. Our findings highlight the identification of circTP63-N, a novel circRNA encoded by an important tumor-relevant gene TP63 and elucidate its molecular mechanism as a tumor suppressor in NPC. These insights offer novel potential molecular markers and therapeutic targets for the clinical diagnosis and treatment of NPC.

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论中国皮鞋产品出口品质的升级——基于价格视角的实证检验

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皮革科学与工程 2025年第1期35卷 70-76页

作者：梁妍婧罗明李明武长江大学经济与管理学院湖北荆州434023 长江大学文理学院湖北荆州434023

中国是全球皮鞋出口大国,但产品主要定位于低端市场。近年来我国一直致力于促进制鞋产业升级,提升出口品质,其成效如何值得关注。基于2010~2022年联合国商品贸易统计数据库中全球皮革类鞋靴产品出口的面板数据,使用单位价值排名法和相... 详细信息

中国是全球皮鞋出口大国,但产品主要定位于低端市场。近年来我国一直致力于促进制鞋产业升级,提升出口品质,其成效如何值得关注。基于2010~2022年联合国商品贸易统计数据库中全球皮革类鞋靴产品出口的面板数据,使用单位价值排名法和相对出口单位价值法(结合价格—品质区间法),测算中国皮鞋产品出口品质变化趋势。研究发现,2010~2017年我国皮鞋出口主要面向低端市场,但出口品质呈现缓慢上升趋势,而从2017~2019年我国皮鞋出口品质迅速上升,在2019年进入中端市场,之后的大多数年份其出口质量都超过了国际市场的平均水平。研究结果有助于厘清我国皮鞋产品在国际市场的地位及其变化趋势,对我国皮鞋企业制定国际市场竞争策略具有一定的参考价值。

关键词：皮鞋产品出口品质变化趋势单位价值排名法相对出口单位价值法

陈旧性骨质疏松性椎体压缩骨折骨不连的修复策略:一项病例分析

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中国组织工程研究 2025年第3期29卷 538-546页

作者：赵星丞王军陆明上海市公共卫生临床中心骨科上海市201508

背景:腰椎骨质疏松性压缩性骨折患者的脊柱和骨盆矢状位参数存在不同程度改变,将导致全脊柱/腰椎矢状面发生失平衡和再平衡。如果初次骨质疏松性椎体压缩骨折没有得到及时治疗,随着时间的推移将发展为陈旧性骨质疏松性椎体压缩骨折骨不... 详细信息

背景:腰椎骨质疏松性压缩性骨折患者的脊柱和骨盆矢状位参数存在不同程度改变,将导致全脊柱/腰椎矢状面发生失平衡和再平衡。如果初次骨质疏松性椎体压缩骨折没有得到及时治疗,随着时间的推移将发展为陈旧性骨质疏松性椎体压缩骨折骨不连。目的:观察陈旧性骨质疏松性腰椎体压缩骨折骨不连9例患者行经皮椎体成形(PVP)术后的修复效果。方法:回顾性分析2018年9月至2022年8月上海市公共卫生临床中心骨科收治的陈旧性老年骨质疏松性腰椎椎体压缩性骨折骨不连经皮椎体成形术后术椎再骨折患者9例的临床资料,所有患者均采用经皮椎体成形行再翻修治疗,同时规律进行抗骨质疏松治疗和康复训练。出院前及随访时复查患者的腰椎X射线平片及三维CT检测结果,评价骨水泥弥散情况,记录患者术前、术后、随访时的目测类比评分、腰椎Oswetry功能障碍指数(ODI评分)及Roussouly腰椎功能分型变化。结果与结论:①9例患者术后随访时均未发生神经损伤、感染、骨水泥椎管内渗漏、肺栓塞及过敏性休克等严重手术并发症,均未发生骨水泥相关的不良反应。有1例患者术后2年感染COVID-19致呼吸功能衰竭死亡。②术椎再骨折患者术后疼痛目测类比评分和ODI评分均显著低于翻修术前,末次随访经皮椎体成形翻修术后患者Roussouly腰椎功能分型显著改善;末次随访测量术椎椎体高度变化与术前比较无显著性意义。③上述结果提示,对陈旧性骨质疏松性腰椎体压缩骨折骨不连行经皮椎体成形治疗的患者而言,适量骨水泥注入和有效骨水泥弥散具有明显缓解术后疼痛作用,规律抗骨质疏松和术后有效康复训练有助于患者术后腰椎功能恢复。

关键词：骨质疏松经皮椎体成形骨水泥注入技术椎体成形术椎再骨折 Roussouly腰椎功能分型应力集中区

不同热处理蛋黄脂质对小鼠学习认知能力下降的缓解能力

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食品工业科技 2025年第1期46卷 367-376页

作者：吴瑶刘铭坤方冰张明合肥工业大学食品与生物工程学院安徽合肥230061 中国农业大学营养与健康系北京100083 北京工商大学食品与健康学院北京100048

为探讨不同温度处理下蛋黄脂质对小鼠学习认知能力下降的缓解能力的差异。本研究利用小鼠认知障碍模型,比较95℃(水浴30 min)和121℃(灭菌锅加热30 min)热处理蛋黄脂质组分改善小鼠学习认知能力的差异。研究结果表明,相较于121℃热处理... 详细信息

为探讨不同温度处理下蛋黄脂质对小鼠学习认知能力下降的缓解能力的差异。本研究利用小鼠认知障碍模型,比较95℃(水浴30 min)和121℃(灭菌锅加热30 min)热处理蛋黄脂质组分改善小鼠学习认知能力的差异。研究结果表明,相较于121℃热处理的蛋黄脂质,95℃热处理的蛋黄脂质更有效地降低了Tau蛋白的磷酸化和Aβ1-40、GSK-3β表达,下调了促炎因子的表达,其提升小鼠的学习记忆能力的效果更好。95℃热处理蛋黄脂质中的多不饱和脂肪酸以及DHA较121℃热处理的蛋黄脂质显著增加(P<0.05)。因此,过度的加热条件,会破坏蛋品中DHA等多不饱和脂肪酸,削弱蛋黄脂质的改善认知的生物活性。本研究为蛋制品的热加工工艺的优化提供参考依据。

关键词：蛋黄脂质热处理学习和记忆