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脂肪酸受体GPR119在动物脂代谢调控中的作用研究进展
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作者 艾庆辉 刘国滨 +2 位作者 卜宪勇 王震 麦康森 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第7期123-129,共7页
中国是水产养殖大国,而高脂饲料的广泛使用导致了鱼类脂肪代谢异常,这严重制约了水产养殖业的发展,亟待对此问题寻求解决方案。近年来在哺乳动物中的研究表明,脂代谢紊乱诱导的非酒精性脂肪肝病(Non-alcoholic fatty liver disease, NAF... 中国是水产养殖大国,而高脂饲料的广泛使用导致了鱼类脂肪代谢异常,这严重制约了水产养殖业的发展,亟待对此问题寻求解决方案。近年来在哺乳动物中的研究表明,脂代谢紊乱诱导的非酒精性脂肪肝病(Non-alcoholic fatty liver disease, NAFLD)是危害动物健康的主要问题之一,而GPR119被认为是治疗NAFLD的新靶点。GPR119在鱼类中的研究相对较少,大部分鱼类GPR119功能相关研究主要聚焦于其在调控鱼类食欲中的作用,而其在调控鱼类脂肪代谢中的作用尚不清楚。本文总结了动物中GPR119基因的结构功能及其对脂肪代谢调控机制的研究现状,旨在为研究GPR119在鱼类脂肪代谢中的作用提供新思路,为探索缓解鱼类脂代谢紊乱的新型策略提供理论参考。 展开更多
关键词 GPR119 脂肪异常沉积 脂代谢 鱼类
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甜椒新品种‘冀研119’的选育
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作者 孟雅宁 范妍芹 +3 位作者 张红肖 张哲 李欣欣 严立斌 《辣椒杂志》 2024年第2期53-57,共5页
‘冀研119’是以甜椒雄性不育两用系AB91-WL11-4322为母本,以自交系MY12-2-6-2-3-2为父本选配成的甜椒杂种一代。中早熟,始花节位在9~11节,植株生长势强,连续坐果能力强,果实灯笼形,3~4心室,果面光滑有光泽,商品成熟果为绿色,生理成熟... ‘冀研119’是以甜椒雄性不育两用系AB91-WL11-4322为母本,以自交系MY12-2-6-2-3-2为父本选配成的甜椒杂种一代。中早熟,始花节位在9~11节,植株生长势强,连续坐果能力强,果实灯笼形,3~4心室,果面光滑有光泽,商品成熟果为绿色,生理成熟时转黄色,果实纵径10.5 cm左右,果实横径8.9 cm,平均单果鲜质量245 g,果实商品性好,感官品质优良,味甜质脆,可溶性糖含量为32.26 mg/g(FW)、Vc含量108.3 mg/100 g(FW);抗病性强,室内及田间抗病性鉴定结果表明,冀研119耐疫病、抗病毒病、中抗炭疽病。每667 m^(2)平均鲜椒产量4 000 kg,适合在河北石家庄、邯郸、张家口、承德等地采用塑料大棚春提前种植,或在石家庄采用日光温室秋延后种植,在邯郸采用塑料大棚秋延后种植。 展开更多
关键词 甜椒 ‘冀研119 杂交一代
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基于美国医学物理学家协会TG119报告的TaiChi加速器质量控制体系建立研究
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作者 庞廷田 王涛 +7 位作者 雷琪琪 杨波 汪之群 张杰 陈胤竹 李世豪 昝鹏 邱杰 《中国医学装备》 2024年第6期1-5,11,共6页
目的:依据美国医学物理学家协会(AAPM)TG119号报告测试方法和项目对TaiChi加速器在RayStation治疗计划系统(简称RayStation系统)中的建模数据模型进行测试评估。方法:在治疗计划系统中按AAPM TG119号报告要求设计模拟多靶区、前列腺靶... 目的:依据美国医学物理学家协会(AAPM)TG119号报告测试方法和项目对TaiChi加速器在RayStation治疗计划系统(简称RayStation系统)中的建模数据模型进行测试评估。方法:在治疗计划系统中按AAPM TG119号报告要求设计模拟多靶区、前列腺靶区、头颈靶区、容易型C形靶区计划和困难型C形靶区计划等不同临床情况测试病例的调强放射治疗(IMRT)和容积旋转调强放射治疗(VMAT)计划,测量两种计划中点剂量和面积量偏差,并将测试结果与AAPM TG119报告中推荐的标准进行对比分析。使用IBA CC13电离室和ArcCHECK矩阵电离室分别对点剂量和面剂量进行验证,评估标准为3%/3mm的γ通过率。采用置信度评判测量剂量与计算剂量的一致性。结果:测试病例计划剂量目标、点剂量偏差及面剂量分布准确性均满足报告要求:测试病例IMRT和VMAT计划的靶区高剂量点平均剂量偏差分别为(0.39±1.02)%和(1.27±0.64)%,置信度分别为2.39%和2.52%。IMRT和VMAT计划的危及器官(OAR)低剂量点平均剂量偏差分别为(0.53±1.73)%和(0.88±1.11)%,置信度分别为3.92%和3.06%。IMRT和VMAT计划3%/3mm标准下的平均γ通过率分别为(99.52±0.366)%和(99.86±0.136)%,置信度分别为1.196%和0.406%。结论:TaiChi加速器性能和Raystation系统6MV FFF模型拟合精度满足AAPM TG119号报告标准,依据此测试结果建立后续设备和患者质控的标准,并为后续加速器性能的改进提供了参考。 展开更多
关键词 美国医学物理家协会(AAPM)TG119报告 加速器 调强放射治疗(IMRT) 容积旋转调强放射治疗(VMAT)
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Future changes in precipitation and water availability over the Tibetan Plateau projected by CMIP6 models constrained by climate sensitivity 被引量:1
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作者 Hui Qiu Tianjun Zhou +3 位作者 Liwei Zou Jie Jiang Xiaolong Chen Shuai Hu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期40-46,共7页
Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assesse... Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity(ECS)and the climatological precipitation performance,the authors constrain the CMIP6(phase 6 of the Coupled Model Intercomparison Project)model projection of summer precipitation and water availability over the TP.The best estimates of precipitation changes are 0.24,0.25,and 0.45 mm d^(−1)(5.9%,6.1%,and 11.2%)under the Shared Socioeconomic Pathway(SSP)scenarios of SSP1–2.6,SSP2–4.5,and SSP5–8.5 from 2050–2099 relative to 1965–2014,respectively.The corresponding constrained projections of water availability measured by precipitation minus evaporation(P–E)are 0.10,0.09,and 0.22 mm d^(−1)(5.7%,4.9%,and 13.2%),respectively.The increase of precipitation and P–E projected by the high-ECS models,whose ECS values are higher than the upper limit of the likely range,are about 1.7 times larger than those estimated by constrained projections.Spatially,there is a larger increase in precipitation and P–E over the eastern TP,while the western part shows a relatively weak difference in precipitation and a drier trend in P–E.The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6℃–1.2℃ under all three scenarios during 2050–2099.This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes. 展开更多
关键词 Tibetan plateau Climate sensitivity Precipitation projection Water availability projection
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Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling 被引量:2
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作者 Yanxin ZHENG Shuanglin LI +2 位作者 Noel KEENLYSIDE Shengping HE Lingling SUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1539-1558,共20页
Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate model... Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather Research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary Research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. Observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6. 展开更多
关键词 triple-nested downscaling Three Gorges Reservoir area consecutive rainfall events geological hazards projectION
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人工智能背景下Materials Project数据库在计算材料学课程教学中的应用
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作者 胡学敏 孙孪鸿 +1 位作者 陈晓玉 叶原丰 《科教文汇》 2024年第10期90-94,共5页
该文探讨了在人工智能背景下,Materials Project数据库在计算材料学课程教学中的应用和影响。Materials Project数据库是一个集成了AI和大数据技术的开放获取的材料库,能为学生提供海量的材料晶体结构和物性数据,使教学内容更为丰富,让... 该文探讨了在人工智能背景下,Materials Project数据库在计算材料学课程教学中的应用和影响。Materials Project数据库是一个集成了AI和大数据技术的开放获取的材料库,能为学生提供海量的材料晶体结构和物性数据,使教学内容更为丰富,让学生能通过亲自操作获取和分析数据,深入理解微观结构与物性之间的关系。这一新兴的教学模式不仅提升了学生的科研能力和创新思维能力,还有助于培养具备计算材料专业知识和多学科交叉的复合型人才。总体来说,人工智能时代下,大数据的引入为计算材料学课程带来新的活力,并对未来教育改革和实践产生了积极影响。 展开更多
关键词 人工智能 Materials project数据库 计算材料学教学
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Transcriptional regulation in the development and dysfunction of neocortical projection neurons 被引量:1
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作者 Ningxin Wang Rong Wan Ke Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期246-254,共9页
Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord... Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations. 展开更多
关键词 autism spectrum disorders COGNITION DIFFERENTIATION excitatory circuits intellectual disability NEOCORTEX neurodevelopmental disorders projection neuron specification transcriptional regulation
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Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method 被引量:1
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作者 Bonan Cao Zengxi Ge 《Earthquake Science》 2024年第2期158-173,共16页
In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back proj... In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks. 展开更多
关键词 2023 Turkish earthquake doublet back projection method cascading segmented rupture process coseismic triggering super-shear ruptures
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AAPM TG119在调强放射治疗技术和容积旋转调强技术中的应用
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作者 吴嘉慧 王凯 胡彩容 《医疗装备》 2024年第18期24-26,31,共4页
目的通过AAPM TG119报告中的测试病例评估Monaco系统调强放射治疗(IMRT)技术和容积旋转调强(VMAT)技术的准确性。方法采用AAPM TG119报告提供的测试病例,在Monaco治疗系统中依照AAPM TG119报告中处方剂量和计划目标要求设计7或9个野的I... 目的通过AAPM TG119报告中的测试病例评估Monaco系统调强放射治疗(IMRT)技术和容积旋转调强(VMAT)技术的准确性。方法采用AAPM TG119报告提供的测试病例,在Monaco治疗系统中依照AAPM TG119报告中处方剂量和计划目标要求设计7或9个野的IMRT计划和单弧或双弧的VMAT计划,采用IBA MatriXX和Compass进行剂量验证,并将计划结果与AAPM TG119报告中多中心测试的结果对比。结果IMRT和VMAT计划在系统中的剂量指标均达到了AAPM TG119报告中的要求。IMRT计划γ通过率(3%/2 mm)为(97.85±1.2)%,VMAT计划的γ通过率(3%/2 mm)为(98.74±1.3)%。结论Monaco系统提供的IMRT技术和VMAT技术能够设计出与AAPM TG119为标准的IMRT计划质量相当的计划。 展开更多
关键词 调强放射治疗 容积旋转调强 AAPM TG119 放射治疗
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Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project 被引量:1
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作者 Astrid E.J.OGILVIE Leslie A.KING +9 位作者 Noel KEENLYSIDE François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels EINARSSON Sergey GULEV Ke FAN Torben KOENIGK James R.MCGOODWIN Marianne H.RASMUSSON Shuting YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1559-1568,共10页
This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sus... This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATH(https://www.svs.is/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATH made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATH was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATH served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities. 展开更多
关键词 Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH project
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三阴性乳腺癌组织中微RNA-331-3p和跨膜蛋白119水平变化与临床预后的相关性
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作者 宋家木 任书伟 +1 位作者 丁小崇 宋洋 《安徽医药》 CAS 2024年第8期1582-1586,共5页
目的探究三阴性乳腺癌(TNBC)组织中微RNA-331-3p(miR-331-3p)和跨膜蛋白119(TMEM119)水平变化与临床预后的相关性。方法选取2017年1月至2019年1月在信阳市中心医院行手术治疗的98例TNBC病人的癌组织以及癌旁组织,分别作为TNBC组和癌旁... 目的探究三阴性乳腺癌(TNBC)组织中微RNA-331-3p(miR-331-3p)和跨膜蛋白119(TMEM119)水平变化与临床预后的相关性。方法选取2017年1月至2019年1月在信阳市中心医院行手术治疗的98例TNBC病人的癌组织以及癌旁组织,分别作为TNBC组和癌旁组。在术后3年对所有病人进行随访,分为预后良好组为23例,预后不良组为75例。通过实时荧光定量PCR(qRT-PCR)法检测miR-331-3p和TMEM119的表达水平;采用Pearson法分析TNBC组织中miR-331-3p和TMEM119表达水平的相关性;分析miR-331-3p和TMEM119水平与TNBC病人预后的关系;影响TNBC病人预后的影响因素采用Cox回归的方法进行分析。结果TNBC组TMEM119(1.53±0.24)的表达水平与癌旁组相比(1.01±0.13)显著上升,miR-331-3p(0.74±0.13)的表达水平与癌旁组(1.02±0.11)相比显著下降(t=41.53、41.53,P<0.05)。Pearson相关性分析结果显示,miR-331-3p和TMEM119表达水平呈负相关关系(r=−0.49,P<0.001)。miR-331-3p和TMEM119表达水平与肿瘤长径、TNM分期、腋窝淋巴结转移有关(P<0.05)。miR-331-3p高表达组病人3年内生存率16/49(32.65%)高于低表达组7/49(14.29%);TMEM119高表达组病人3年内生存率4/49(8.16%)低于低表达组19/49(38.78%)(Z=4.60,P=0.032;Z=12.78,P<0.001)。预后不良组miR-331-3p(0.65±0.13)表达水平与预后良好组(1.03±0.12)相比显著降低,TMEM119(1.69±0.27)表达水平与预后良好组(1.02±0.14)相比显著升高(t=38.74、33.30,P<0.05)。结果显示,TNM分期(HR=5.88)、miR-331-3p(HR=2.45)和TMEM119(HR=2.86)表达水平是影响TNBC病人预后的危险因素(P<0.05)。结论TNBC病人癌组织中miR-331-3p低表达,TMEM119高表达,二者水平与预后评估密切相关。 展开更多
关键词 三阴性乳腺癌 微小RNA-331-3p 跨膜蛋白119 预后
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Diagnosis of indirectly driven double shell targets with point-projection hard x-ray radiography
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作者 Chao Tian Minghai Yu +17 位作者 Lianqiang Shan Fengjuan Wu Bi Bi Qiangqiang Zhang Yuchi Wu Tiankui Zhang Feng Zhang Dongxiao Liu Weiwu Wang Zongqiang Yuan Siqian Yang Lei Yang Zhigang Deng Jian Teng Weimin Zhou Zongqing Zhao Yuqiu Gu Baohan Zhang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期50-62,共13页
We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on t... We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated. 展开更多
关键词 double projectION POINT
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Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems
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作者 You Zhao Xing He +1 位作者 Mingliang Zhou Tingwen Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1485-1498,共14页
The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on... The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments. 展开更多
关键词 Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.
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Quantum block coherence with respect to projective measurements
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作者 王璞 李忠艳 孟会贤 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期213-220,共8页
Quantum coherence serves as a defining characteristic of quantum mechanics,finding extensive applications in quantum computing and quantum communication processing.This study explores quantum block coherence in the co... Quantum coherence serves as a defining characteristic of quantum mechanics,finding extensive applications in quantum computing and quantum communication processing.This study explores quantum block coherence in the context of projective measurements,focusing on the quantification of such coherence.Firstly,we define the correlation function between the two general projective measurements P and Q,and analyze the connection between sets of block incoherent states related to two compatible projective measurements P and Q.Secondly,we discuss the measure of quantum block coherence with respect to projective measurements.Based on a given measure of quantum block coherence,we characterize the existence of maximal block coherent states through projective measurements.This research integrates the compatibility of projective measurements with the framework of quantum block coherence,contributing to the advancement of block coherence measurement theory. 展开更多
关键词 quantum coherence compatibility projective measurement quantum block coherence
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REFINEMENTS OF THE NORM OF TWO ORTHOGONAL PROJECTIONS
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作者 Xiaohui LI Meiqi LIU Chunyuan DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1229-1243,共15页
In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm ineq... In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm inequalities for combination of orthogonal projections on a Hilbert space.Furthermore,we give necessary and sufficient conditions under which the norm of the above combination of o`rthogonal projections attains its optimal value. 展开更多
关键词 NORM orthogonal projection positive operator SPECTRAL block operator valued matrix
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Fudan multi-purpose active target time projection chamber(fMeta-TPC)for photonuclear reaction experiments
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作者 Huang-Kai Wu Xi-Yang Wang +8 位作者 Yu-Miao Wang You-Jing Wang De-Qing Fang Wan-Bing He Wei-Hu Ma Xi-Guang Cao Chang-Bo Fu Xian-Gai Deng Yu-Gang Ma 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期140-151,共12页
Active target time projection chambers are state-of-the-art tools in the field of low-energy nuclear physics and are particularly suitable for experiments using low-intensity radioactive ion beams or gamma rays.The Fu... Active target time projection chambers are state-of-the-art tools in the field of low-energy nuclear physics and are particularly suitable for experiments using low-intensity radioactive ion beams or gamma rays.The Fudan multi-purpose active target time projection chamber(fMeta-TPC)with 2048 channels was developed to studyα-clustering nuclei.This study focused on the photonuclear reaction with a laser Compton scattering gamma source,particularly for the decay of the highly excitedαcluster state.The design of fMeta-TPC is described in this paper.A comprehensive evaluation of its offline performance was conducted using an ultraviolet laser and ^(241)Amαsource.The results showed that the intrinsic angular resolution of the detector was within 0.30°,and the detector had an energy resolution of 6.85%for 3.0 MeVαparticles.The gain uniformity of the detector was approximately 10%(RMS/Mean),as tested by the ^(55)Fe X-ray source. 展开更多
关键词 Active target Time projection chambers Photonuclear reaction αcluster
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GLOBAL CONVERGENCE OF A CAUTIOUS PROJECTION BFGS ALGORITHM FOR NONCONVEX PROBLEMS WITHOUT GRADIENT LIPSCHITZ CONTINUITY
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作者 Gonglin YUAN Xiong ZHAO Jiajia YU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1735-1746,共12页
A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gr... A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS method.Under some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection technique.Finally,the effectiveness and application prospects of the proposed method are verified by numerical experiments. 展开更多
关键词 cautious BFGS nonconvex problems Lipschitz continuity projection technique global convergence
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Progress of Taiji-2 Project
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作者 LUO Ziren ZHANG Min +1 位作者 WANG Jianyu WU Yueliang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期674-676,共3页
Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced ... Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced here. 展开更多
关键词 Gravitational wave Taiji program Taiji-2 project
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Evaluation and projection of marine heatwaves in the South China Sea: insights from CMIP6 multi-model ensemble
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作者 Kai Liu Kang Xu +4 位作者 Tongxin Han Congwen Zhu Nina Li Anboyu Guo Xiaolu Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期15-25,共11页
This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2... This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 models.Results demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best performance.The reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature trend.Under various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and amplitudes.This is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after 2040.Furthermore,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future periods.However,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP scenarios.During the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter durations.In contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 scenarios.However,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state. 展开更多
关键词 marine heatwaves South China Sea global warming future projections CMIP6
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Construction and Research Progress of the Chinese Meridian Project in 2022–2023
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作者 WANG Chi CHEN Zhiqing XU Jiyao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期704-711,共8页
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing... The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research. 展开更多
关键词 Chinese Meridian project(CMP) MAGNETOSPHERE IONOSPHERE Middle and upper atmosphere
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