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ASPECTS评分及多模态CT定量分析在AIS预后预测中的应用
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作者 王书芹 郑璇 +1 位作者 孟影 朱广辉 《中国CT和MRI杂志》 2024年第11期4-6,共3页
目的探讨ASPECTS评分及多模态CT中各参数在急性缺血性脑卒中(AIS)预后预测的应用价值。方法收集2019年1月-2023年4月诊断为AIS并在蚌埠医学院第一附属医院就诊的患者,在治疗前均行多模态CT(包括NCCT、CTA、CTP)检查的患者93例,3个月后... 目的探讨ASPECTS评分及多模态CT中各参数在急性缺血性脑卒中(AIS)预后预测的应用价值。方法收集2019年1月-2023年4月诊断为AIS并在蚌埠医学院第一附属医院就诊的患者,在治疗前均行多模态CT(包括NCCT、CTA、CTP)检查的患者93例,3个月后随访并根据改良Rankin量表评分(mRs)将患者分为预后良好组(mRs≤2)和预后不良组(mRs>2),收集两组患者的临床资料及多模态CT定量参数比较其在预测AIS中预后中有无意义。结果一般资料分析可见预后不良组患者入院基线NIHSS评分、远端侧支循环及ASPECTS评分均与预后良好组之间有一定的统计学差异(P<0.05);CT灌注定量参数分析可见预后不良组CBF较低,而MTT、Tmax、TTP较预后良好组延长,且具有统计学意义(P<0.05)。其中NIHSS、远端侧支循环及Tmax为影响AIS预后的独立危险因素。结论NIHSS、远端侧支循环、ASPECTS及多模态CT可以对AIS的预后进行评测。均具有较好的预测效能,其中Tmax及NIHSS预测效能最好。 展开更多
关键词 脑卒中 aspects评分 多模态CT CT灌注
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颈动脉斑块MRI特征与同侧急性脑梗死患者DWIGASPECTS的相关性研究 被引量:2
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作者 王贝茹 余苗 +2 位作者 徐彤彤 李均彪 胡春峰 《放射学实践》 CSCD 北大核心 2024年第1期49-54,共6页
目的:探讨颈动脉斑块MRI特征与同侧急性脑梗死患者DWI-ASPECTS的相关性。方法:回顾性搜集我院85例颈动脉斑块患者的临床及影像资料,所有患者均于出现脑血管症状2周内行颈动脉高分辨率MRI和常规颅脑MRI平扫。将患者分为DWI-ASPECTS≤7分... 目的:探讨颈动脉斑块MRI特征与同侧急性脑梗死患者DWI-ASPECTS的相关性。方法:回顾性搜集我院85例颈动脉斑块患者的临床及影像资料,所有患者均于出现脑血管症状2周内行颈动脉高分辨率MRI和常规颅脑MRI平扫。将患者分为DWI-ASPECTS≤7分组和DWI-ASPECTS>7分组,比较两组间临床、实验室资料和颈动脉斑块定量、定性指标的差异。通过Logistic回归筛选DWI-ASPECTS评分的预测因子。结果:25例(29.4%)DWI-ASPECTS≤7分,60例(70.6%)DWI-ASPECTS>7分。DWI-ASPECTS≤7分组患者纤维帽变薄/破裂(分别为80.0%和35.0%,P<0.001)、斑块内出血(分别为72.0%和21.7%,P<0.001)、钙化(分别为76.0%和45.0%,P=0.009)和富脂质坏死核心(分别为72.0%和45.0%,P=0.023)的发生率均高于DWI-ASPECTS>7分组;此外,DWI-ASPECTS≤7分组患者显示出更高的斑块负荷,DWI-ASPECTS≤7分组与DWI-ASPECTS>7分组的最大管壁厚度[分别为(4.38±1.68)和(3.47±1.78)mm,P=0.033]、平均管腔面积[分别为(15.33±11.57)和(22.88±13.95)mm 2,P=0.019]、最小管腔面积[分别为(11.52±11.23)和(18.98±13.52)mm 2,P=0.017]、平均管壁面积[分别为(62.81±14.32)、(55.66±14.93)mm 2,P=0.045]、最大管壁面积[分别为(66.70±14.57)、(59.56±15.19)mm 2,P=0.049]、平均标准化管壁面指数[分别为(81±14)%、(71±16)%,P=0.011]、最大标准化管壁指数[分别为(86±14)%、(76±16)%,P=0.012)]差异均有统计学意义。DWI-ASPECTS≤7分组中NIHSS评分>4分的患者比例更高(分别为48%和23.3%,P=0.025),高密度脂蛋白浓度更低[分别为(1.24±0.28)、(1.10±0.28)mmol/L,P=0.043]。Logistic回归分析结果显示,纤维帽变薄/破裂(OR=4.133,95%CI:1.151~14.836,P=0.030)和斑块内出血(OR=6.409,95%CI:1.737~23.646,P=0.005)与较低的DWI-ASPECTS评分显著相关。结论:颈动脉斑块中存在纤维帽变薄/破裂和斑块内出血的急性脑卒中患者DWI-ASPECTS评分更低,有助于评估患者的病情严重程度。 展开更多
关键词 颈动脉斑块 磁共振成像 DWI-aspects评分 急性脑梗死
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DWI-ASPECTS评分联合血清Hcy、LDL-C、Lp-PLA2对急性脑梗死静脉溶栓患者预后不良的预测价值
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作者 王刚 张博 +2 位作者 吕凤华 曲立新 魏伟 《检验医学与临床》 CAS 2024年第18期2642-2646,共5页
目的分析弥散加权成像-阿尔伯塔卒中项目早期计算机断层扫描(DWI-ASPECTS)评分联合血清同型半胱氨酸(Hcy)、低密度脂蛋白胆固醇(LDL-C)、脂蛋白磷脂酶A2(Lp-PLA2)对急性脑梗死(ACI)静脉溶栓患者预后不良的预测价值。方法回顾性分析2021... 目的分析弥散加权成像-阿尔伯塔卒中项目早期计算机断层扫描(DWI-ASPECTS)评分联合血清同型半胱氨酸(Hcy)、低密度脂蛋白胆固醇(LDL-C)、脂蛋白磷脂酶A2(Lp-PLA2)对急性脑梗死(ACI)静脉溶栓患者预后不良的预测价值。方法回顾性分析2021年3月至2023年9月山东大学齐鲁医院德州医院收治的102例ACI患者的临床资料,静脉溶栓3个月后以改良Rankin量表(mRS)评估患者预后,根据mRS评分将患者分为预后良好组(mRS评分≤2分)与预后不良组(mRS评分>2分)。比较两组基线资料及血清Hcy、LDL-C、Lp-PLA2水平及DWI-ASPECTS评分。绘制受试者工作特征(ROC)曲线分析DWI-ASPECTS评分联合血清Hcy、LDL-C、Lp-PLA2对ACI静脉溶栓患者预后不良的预测价值。结果预后不良组有35例患者,预后良好组有67例患者。预后不良组美国国立卫生研究院卒中量表(NIHSS)评分及Hcy、LDL-C、Lp-PLA2水平高于预后良好组,DWI-ASPECTS评分低于预后良好组,差异均有统计学意义(P<0.05)。ROC曲线分析结果显示,DWI-ASPECTS评分联合Hcy、LDL-C、Lp-PLA2评估ACI静脉溶栓患者预后不良的曲线下面积(AUC)大于DWI-ASPECTS评分、Hcy、LDL-C、Lp-PLA2单独预测的AUC(Z=3.548、3.316、3.996、4.009,P<0.05)。结论DWI-ASPECTS评分及血清Hcy、LDL-C、Lp-PLA2均对ACI静脉溶栓患者预后不良具有一定的预测价值,且其联合检测可提高预测价值。 展开更多
关键词 同型半胱氨酸 急性脑梗死 静脉溶栓 预后评估 低密度脂蛋白胆固醇 基于弥散加权成像-阿尔伯塔卒中项目早期计算机断层扫描评分
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Management of Significant Environmental Aspects and Impacts in Accordance with the ISO 14001:2015 Standard during the Operation and Maintenance Phase of Senegal River Basin Development Authority Hydroelectric Works and Facilities: The Case of Manantali Dam
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期89-110,共22页
This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version ... This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version 2015 standard. To do this, the mapping of the different work areas made it possible to identify all the activities within the framework of the farm. Based on the mapping, environmental measurements made including noise level, brightness, electric and magnetic fields, total particles, PM10, PM2.5, PM1 showed the work areas with the exposure limit values exceeded. The inventories of the waste produced show eighteen (18) types of waste, 67% of which are special industrial waste (SIW), 28% are ordinary industrial waste (OIW) and 5% are inert industrial waste (IIW). The identification and assessment of environmental aspects and impacts made it possible to determine sixteen (16) positive and negative significant environmental aspects (ESAs). The positive AES must be maintained, and for the negative ones, mitigation and mitigation measures must be put in place in order to manage them effectively. This will ultimately improve environmental management in the operation of hydroelectric structures and facilities. 展开更多
关键词 Manantali Environmental aspect Environmental Impact Waste Mitigation and Mitigation Measures
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Psychosocial Aspects of Male Infertility at the Service of Urology-Andrology of the Hospital of the Sino-Guinean Friendship
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作者 Alimou Diallo Thierno Oumar Diallo +3 位作者 Alpha Oumar Barry Ibrahima Bah Abdoulaye Bobo Diallo Oumar Raphiou Bah 《Open Journal of Urology》 2024年第7期400-406,共7页
Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The ... Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The study covered 17 patients, all received for a desire to conceive after at least one year of regular sexual intercourse without contraception. The data were collected from patient interviews using a pre-established questionnaire. Results: The average age of the patients was 32.07 years with extremes of 23 years and 42 years. During this study, 64.70% of patients were no longer participating in community ceremonies. The patients’ relationships with their spouse and family deteriorated in 52.94% and 47.06%, respectively. Conversely, relations with the family of origin remained unchanged in 70.59 percent of cases. The reduction in economic activity was by 13 patients (76.48%). Conclusion: Male infertility causes a real psychic earthquake in men with its corollaries of negative feelings. The rather complex moral repercussions of male infertility affect not only the individual, his/her partner, and family, but also economic activity. 展开更多
关键词 Male Infertility Psycho-Social aspect Psychic Earthquake
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人工智能在急性缺血性脑卒中早期ASPECTS评估中的研究进展 被引量:3
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作者 方婷 杨一风 +1 位作者 贾守强 聂生东 《中国医学物理学杂志》 CSCD 2023年第8期1045-1050,共6页
急性缺血性脑卒中(AIS)的早期诊断和及时干预对于降低脑卒中的致死致残率具有重要意义。目前,临床上采用阿尔伯塔卒中项目早期计算机断层扫描评分(ASPECTS)来评估AIS的严重程度,但人为评估方法主观性过强且耗时耗力,极易导致漏诊、误诊... 急性缺血性脑卒中(AIS)的早期诊断和及时干预对于降低脑卒中的致死致残率具有重要意义。目前,临床上采用阿尔伯塔卒中项目早期计算机断层扫描评分(ASPECTS)来评估AIS的严重程度,但人为评估方法主观性过强且耗时耗力,极易导致漏诊、误诊。因此,近年来涌现了许多基于人工智能算法对AIS进行ASPECTS自动评分的方法研究。本文对此进行综述,以期为进一步研究探索提供参考。首先,简述ASPECTS评分的可靠性;其次,重点介绍目前基于人工智能的脑区提取及脑区评分的方法,证实计算机辅助ASPECTS评分能够有效提高对病情判断的可靠性;最后,总结现有ASPECTS自动评分方法存在的不足,并对其未来的发展趋势进行展望。 展开更多
关键词 aspects评分 急性缺血性脑卒中 人工智能 自动化评分 综述
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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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Influence of quarantine during the coronavirus disease 2019(COVID-19)pandemic on physical and psychosocial aspects:perceptions of 214 Brazilian athletes
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作者 Eliane de Morais Machado Leonardo Luiz Barretti Secchi +1 位作者 Paula Rezende Camargo Luciana De Michelis Mendonca 《Global Health Journal》 2023年第1期49-54,共6页
Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their ph... Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their physical and psychosocial aspects,sleep quality and coping strategies during the quarantine of the coronavirus disease 2019(COVID-19)pandemic.Methods:This was a cross-sectional study with online survey,performed with Brazilian athletes(amateur and professional)over 18 years.The main outcomes measures assessed were physical and psychosocial aspects,sleep quality and coping strategies.Results:A total of 214 athletes were included.The average weekly hours of training during the quarantine was 4.71±3.71 h,of which 64.5%athletes(138/214)were oriented by medical staff during training.For 52.8%(113/214)of athletes,training intensity during the quarantine was different/very different from the intensity before the quarantine.79.4%athletes(170/214)reported moderate to extreme difficulties in keeping the same level of training during the quarantine.77.1%athletes(165/214)had moderate to extreme anxiety and each of the athletes had concern about his or her athletic career future,including return to the sport.72.9%athletes(156/214)reported change in sleep schedule during the quarantine period.Conclusion:The quarantine period during COVID-19 pandemic negatively affected the athlete^perception about training routine,since athletes reported reduction in training hours and training intensity.Overall,the athletes reported that they were moderately to extremely anxious.They also had concerns about their career in the future,as well as concerns regarding return to sport. 展开更多
关键词 Social isolation Performance Psychological aspects Sleep quality Sport
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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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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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Mathematical Aspects of SU (2) and SO(3,R) Derived from Two-Mode Realization in Coordinate-Invariant Form
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作者 Alfred Wünsche 《Journal of Modern Physics》 CAS 2023年第3期361-413,共53页
Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter  instead of the Euler angles and ... Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter  instead of the Euler angles and the vector parameter c of Fyodorov are developed. The one-dimensional root scheme of SU (2) is embedded in two-dimensional root schemes of some higher Lie groups, in particular, in inhomogeneous Lie groups and is represented in text and figures. The two-dimensional fundamental representation of SU (2) is calculated and from it the composition law for the product of two transformations and the most important decompositions of general transformations in special ones are derived. Then the transition from representation of SU (2) to of is made where in addition to the parametrization by vector  the convenient parametrization by vector c is considered and the connections are established. The measures for invariant integration are derived for and for SU (2) . The relations between 3D-rotations of a unit sphere to fractional linear transformations of a plane by stereographic projection are discussed. All derivations and representations are tried to make in coordinate-invariant way. 展开更多
关键词 Boson Operators Lie Algebra Root Diagram Invariant Integration Hamilton-Cayley Identity Cayley-Gibbs-Fyodorov Parametrization Composition Law Quaternion Stereographic projection Fractional Linear Transformation
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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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Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface
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作者 Zhiwei Li Jianfu Zhang +3 位作者 Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期449-467,共19页
High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effect... High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing techniques.This study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect ratio.Unlike conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving tool.The tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material deformation.Thanks to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling off.Since one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of EV-chiseling.Next,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process parameters.Then,surface texturing tests are performed on copper to verify the efficacy of EV-chiseling.Uniformed micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on copper.Compared with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 times.The experimental results also verify the accuracy of the developed surface generation model of microstructures.Finally,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed. 展开更多
关键词 metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation
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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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