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Enhanced red luminescence of Ca_(3)Si_(2−x)M_(x)O_(7):Eu^(3+)(M=Al,P)phosphors via partial substitution of Si^(4+) for applications in white light-emitting diodes

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Rare Metals 2024年第2期43卷 736-748页

作者： Yu-Hao Ma Xi Gao Wen-Tao Zhang Zhen-Rui Yang zhou zhao Chen Qu College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China International Advanced Energy Science Research and Education Center Graduate School of Energy ScienceKyoto UniversityYoshida-HonmachiKyoto606-8501Japan

A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were investigated.The X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) ions.The characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) ions.After the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal stability.Moreover,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity features.In summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.

关键词： Ca_(3)Si_(2)O_(7) Red-emitting phosphor Structure substitution Luminescence enhancement Crystal-field effect White light-emitting diode

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Discovery of proqodine A derivatives with antitumor activity targeting NAD(P)H:quinone oxidoreductase 1 and nicotinamide phosphoribosyltransferase

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Chinese Journal of Natural Medicines 2024年第1期22卷 75-88页

作者： SONG Jiangzhou ZOU Guiqing zhao zhou ZHU Ya XUE Jiayu AO Lanjia SUN Huiyong HAO Haiping ZHANG Bo XU Xiaowei State Key Laboratory of Natural Medicines Key Lab of Drug Metabolism and PharmacokineticsChina Pharmaceutical UniversityNanjing 210009China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

NAD(P)H:quinone oxidoreductase 1(NQO1)is a flavin protease highly expressed in various cancer cells.NQO1 catalyzes a futile redox cycle in substrates,leading to substantial reactive oxygen species(ROS)production.This ROS generation results in extensive DNA damage and elevated poly(ADP-ribose)polymerase 1(PARP1)-mediated consumption of nicotinamide adenine dinucleotide(NAD^(+)),ultimately causing cell death.Nicotinamide phosphoribosyltransferase(NAMPT),the rate-limiting enzyme in the NAD^(+)salvage synthesis pathway,emerges as a critical target in cancer therapy.The concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD+depletion.In this study,we designed,synthesized,and assessed a novel series of proqodine A derivatives targeting both NQO1 and NAMPT.Among these,compound T8 demonstrated potent antitumor properties.Specifically,T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and NAMPT.This discovery offers a promising new molecular entity for advancing anticancer research.

关键词： NQO1 ROS NAMPT NAD^(+) T8

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Prognostic significance of hemoglobin,albumin,lymphocyte,platelet in gastrointestinal stromal tumors:A propensity matched retrospective cohort study

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World Journal of Gastroenterology 2022年第27期28卷 3476-3487页

作者： zhou zhao Xiao-Nan Yin Jian Wang Xin Chen zhao-Lun Cai Bo Zhang Department of Gastrointestinal Surgery Sichuan University West China HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND The combined index of hemoglobin,albumin,lymphocyte,and platelet(HALP)can reflect systemic inflammation and nutritional status simultaneously,with some evidence revealing its prognostic value for some tumors.However,the effect of HALP on recurrence-free survival(RFS)in patients with gastrointestinal stromal tumors(GISTs)has not been reported.AIM To investigate the prognostic value of HALP in GIST patients.METHODS Data from 591 untreated patients who underwent R0 resection for primary and localized GISTs at West China Hospital between December 2008 and December 2016 were included.Clinicopathological data,preoperative albumin,blood routine information,postoperative treatment,and recurrence status were recorded.To eliminate baseline inequivalence,the propensity scores matching(PSM)method was introduced.Ultimately,the relationship between RFS and preoperative HALP was investigated.RESULTS The optimal cutoff value for HALP was determined to be 31.5 by X-tile analysis.HALP was significantly associated with tumor site,tumor size,mitosis,Ki67,National Institutes of Health(NIH)risk category,and adjuvant therapy(all P<0.001).Before PSM,GIST patients with an increased HALP had a significantly poor RFS(P<0.001),and low HALP was an independent risk factor for poor RFS[hazard ratio(HR):0.506,95%confidence interval(95%CI):0.291-0.879,P=0.016].In NIH high-risk GIST patients,GIST patients with low HALP had a worse RFS than patients with high HALP(P<0.05).After PSM,458 GIST patients were identified;those with an increased HALP still had significantly poor RFS after PSM(P<0.001)and low HALP was still an independent risk factor for poor RFS(HR:0.558,95%CI:0.319-0.976,P=0.041).CONCLUSION HALP was significantly correlated with postoperative pathology and postoperative treatment.Furthermore,HALP showed a strong ability to predict RFS in GIST patients who underwent radical resection.

关键词： Gastrointestinal stromal tumors Nutrition assessment Immuno-inflammatory-based prognostic scores Prognosis Propensity score

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“增长友好型”理念下涉外税制的调整优化——高质量共建“一带一路”的视角

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税收经济研究 2024年第2期29卷 49-55页

作者：赵洲赵翰隽南京审计大学南京审计大学法学院

自2016年G20中国杭州峰会以来,“增长友好型”税收制度及政策理念得到充分确认和强化。为适应和促进高质量共建“一带一路”的新进程,我国应引领塑造“增长友好型”涉外税制的共识理念。以此为基础,不断调整优化我国与“一带一路”各国... 详细信息

自2016年G20中国杭州峰会以来,“增长友好型”税收制度及政策理念得到充分确认和强化。为适应和促进高质量共建“一带一路”的新进程,我国应引领塑造“增长友好型”涉外税制的共识理念。以此为基础,不断调整优化我国与“一带一路”各国的涉外税制、政策以及协调合作,消除阻碍经济增长与创新发展的税收壁垒与障碍。为此,应进一步调整优化涉外优惠税制,并使其与“支柱二”规则实现协调兼容。同时,细化明确税收协定中的饶让抵免条款,适当引入相应的国际税收规则,以增强我国涉外税收政策的确定性。

关键词：增长友好型确定性 “一带一路” 税收协定税收优惠

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基于空间拓扑条件控制的等高线化简方法

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地球信息科学学报 2024年第7期26卷 1659-1671页

作者：李元復孙群温伯威周炤朱蕊中国人民解放军战略支援部队信息工程大学地理空间信息学院郑州450052

等高线是地形图上的重要要素之一,其化简过程需要兼顾主要地形结构特征的保持、数据精度的控制以及相交和视觉混淆的避免等问题,现有研究大多没有同时兼顾这3个方面。针对上述问题,本文在现有方法使用的误差带的基础上,进一步引入隔离... 详细信息

等高线是地形图上的重要要素之一,其化简过程需要兼顾主要地形结构特征的保持、数据精度的控制以及相交和视觉混淆的避免等问题,现有研究大多没有同时兼顾这3个方面。针对上述问题,本文在现有方法使用的误差带的基础上,进一步引入隔离带的概念,并对它们在几何中的定义进行数学描述,提出将空间拓扑条件应用于等高线化简的策略。根据这一策略,对谷地弯曲选取(Valley Bend Selection,VBS)算法和Douglas-Peucker(DP)算法进行改进,从而得到空间拓扑条件控制下的VBS(Spatial-Topologic-Condition-Controlled VBS,STCC-VBS)算法和空间拓扑条件控制下的DP(Spatial-Topologic-Condition-Controlled DP,STCC-DP)算法。最后,将这2种方法应用于1:5万比例尺地形图等高线化简生成1:10万比例尺地形图等高线的任务中,并与现有的2种单纯以误差带控制的等高线化简方法进行对比。实验结果表明,STCC-VBS算法和STCC-DP算法都有效避免了相交问题,同时以改进前的方法为参考,在算法参数相同的情况下,分别在节点约减率降低8.33%和2.06%同时,使等高线偏移率降低了22.97%和12.65%,化简效果得到显著改善。其中,STCC-VBS算法在约减54.58%的节点的同时,仍能使地形特征线保持率达到94.73%,在有效约减数据量的前提下,较好地保持了主要地形特征。2种算法在效率方面均优于2种单纯以误差带控制的等高线化简方法。

关键词：地形等高线数字高程模型制图综合线化简误差带隔离带空间拓扑条件

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触觉传感器的柔性化方法及其应用研究综述

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传感器与微系统 2024年第7期43卷 6-10页

作者：周昭高国伟北京信息科技大学传感器北京市重点实验室北京100101 北京信息科技大学现代测控技术教育部重点实验室北京100192

触觉传感器是一种模拟人体触觉并用于检测外部刺激的设备,触觉传感器的柔性化也成为了研究的关键点之一。本文介绍了不同类型的柔性触觉传感器(电容式、压阻式、摩擦电等)。采用纳米复合材料并结合静电纺丝法、旋涂法、以及新出现的喷... 详细信息

触觉传感器是一种模拟人体触觉并用于检测外部刺激的设备,触觉传感器的柔性化也成为了研究的关键点之一。本文介绍了不同类型的柔性触觉传感器(电容式、压阻式、摩擦电等)。采用纳米复合材料并结合静电纺丝法、旋涂法、以及新出现的喷涂法等制备的柔性触觉传感器具有灵敏度高、响应速度快等特点,并对柔性触觉传感器应用领域进行了总结和展望。

关键词：柔性触觉传感器柔性化方法应用研究

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魏晋南北朝落座环境及坐具设计中的同构性

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家具与室内装饰 2024年第3期31卷 9-13页

作者：刘晨晨赵舟西安美术学院科研创作处陕西西安710065 西安美术学院建筑环境艺术系陕西西安710065

本文旨在探讨魏晋南北朝时期落座环境及家具设计在转变时期的艺术特征。以传统美学设计审美的流变为主线,对魏晋南北时期的人居小环境及家具设计进行分类交叉对比研究。采用学科交叉的研究思路,使用文献与图像相互印证的研究方法,从魏... 详细信息

本文旨在探讨魏晋南北朝时期落座环境及家具设计在转变时期的艺术特征。以传统美学设计审美的流变为主线,对魏晋南北时期的人居小环境及家具设计进行分类交叉对比研究。采用学科交叉的研究思路,使用文献与图像相互印证的研究方法,从魏晋南北时期社会环境与起居习惯这两方面入手分析资料,对魏晋时期影响家具设计转变的因素进行研究。分析出魏晋南北时期落座环境与家具设计转变的主要原因为以下三方面:礼制观念在此时期的转变;传统造物观念的传承;胡化起居习惯的影响。探析出魏晋南北朝时期落座环境与家具设计的艺术特征,展现了在社会融合转变时期,传统文化在设计造物中的重要影响。表明在当代设计环境中,传统造物观是奠定当代家具设计走向现代新发展道路的重要基石。

关键词：落座环境家具设计礼易同构性坐具设计

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Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1743-1753页

作者： WANG Hejing YUAN Lei WANG Ling zhou zhao AN Jiali School of Earth and Space Sciences Peking University Key Laboratory of Orogenic Belt and Crustal Evolution Ministry of Education

This study uses illite crystallinity,chlorite crystallinity,illite polytypes,the b0 cell-dimension of K-white mica,clay mineral assemblages and mineral geothermo-geobarometers to investigate the overprint of diagenesis and metamorphism on the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang in northeastern Hunan Province,China.Illite crystallinity Kbler index（KI） of the 〈2μm fractions ranges from 0.225 to 0.485°Δ2θ while chlorite crystallinity Arkai index（AI） ranges from 0.244 to 1.500°Δ2θ.This indicates that the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang were overprinted with diagenesis and anchi- to epimetamorphism.Peak metamorphic temperature is estimated with the IV site chlorite geothermometer roughly at 360℃.The b0 cell dimension values of illites（K-mica） range from 0.9002 to 0.9054 nm and,on average,at 0.9030 nm for the Meso-Neoproterozoic.Based on cumulative frequency curves of illite（K-mica） b0 cell dimension,the peak metamorphic pressure of the MesoNeoproterozoic along the profile Yueyang-Linxiang is derived of an intermediate pressure type.Most illites occur in the 2M1 polytype and some of them in a mixture of 2M1＋1M types especially those in the Paleozoic.This result partly agrees with the conclusion of the lower greenschist and greenschist facies of the Lengjiaxi and Banxi Groups.However,it is not agreed with the sedimentary cover from the Sinian to the Lower Paleozoic or from the Banxi Group to the Lower Paleozoic.Crustal thickening due to ＂collision＂ between the Yangtze and Cathaysia blocks led to an increase in the thickness of the Meso-Neoproterozoic to ca.14 km and resulted in a temperature increase in those rocks due to burial.The very low grade to low grade metamorphism overprinting the Meso-Neoproterozoic implies that the so called ＂Chiangnania or Jiangnan orogen＂ was no relative with the ＂Grenvillian orogeney;instead,it might be a continuous amalgamation product between the Yangtze and Cathaysia blocks.

关键词： diagenesis very low-grade metamorphism illite crystallinity Meso-Neoproterozoic lowerpalaeozoic

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数字金融发展能够改善市场非理性现象吗?——机构投资者羊群行为视角

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现代财经（天津财经大学学报） 2024年第4期44卷 90-109页

作者：周兆斌杨志国中国财政科学研究院北京100142

机构投资者的投资行为是资本市场“风向标”,探讨如何减少机构投资者羊群行为对于促进资本市场稳定运行具有重要意义。本文以2013年至2021年A股上市公司数据为样本,实证考察了数字金融发展对机构投资者羊群行为的影响。研究发现,数字金... 详细信息

机构投资者的投资行为是资本市场“风向标”,探讨如何减少机构投资者羊群行为对于促进资本市场稳定运行具有重要意义。本文以2013年至2021年A股上市公司数据为样本,实证考察了数字金融发展对机构投资者羊群行为的影响。研究发现,数字金融可以有效抑制机构投资者羊群行为,且数字金融覆盖广度、使用深度与数字化程度对机构投资者羊群行为均具有显著抑制作用。机制检验表明,数字金融可以通过增加分析师关注、提高会计信息可比性、促进机构投资者实地调研来减少机构投资者羊群行为。进一步研究表明,数字金融对机构投资者羊群行为的影响在小规模企业及非国有企业中更为显著;区分机构投资者信息竞争水平发现,数字金融对机构投资者羊群行为的抑制作用在私有信息竞争激烈的样本中更为显著;区分机构投资者类型发现,压力抵制型机构投资者能够促进数字金融对机构投资者羊群行为的抑制作用;资本市场经济效应检验发现,数字金融通过抑制机构投资者羊群行为,提高股票流动性,推动了资本市场运行效率提升。本文基于数字金融视角,为如何抑制机构投资者羊群行为这一非理性现象提供了新的思路。研究对于进一步发挥数字金融技术潜力,促进资本市场稳定运行提供了新的借鉴和参考。

关键词：数字金融机构投资者羊群行为分析师关注会计信息可比性机构投资者实地调研

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The Study of the Graft Hemodynamics with Different Instant Patency in Coronary Artery Bypassing Grafting

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Computer Modeling in Engineering & Sciences 2018年第8期116卷 229-245页

作者： zhou zhao Boyan Mao Youjun Liu Haisheng Yang Yu Chen Cardiac Surgery Department Peking University People’s Hospital.11th.Ave.XizhimenBeijingChina. College of Life Science and Bio-engineering Beijing University of Technology.No.100 PingleyuanChaoyang DistrictBeijingChina.

In coronary artery bypass grafting(CABG),graft’s poor instant patency may lead to an abnormal hemodynamic environment in anastomosis,which could further cause graft failure after the surgery.This paper investigates the graft hemodynamics with different instant patency,and explores its effect on graft postoperative efficiency.Six CABG 0D/3D coupling multi-scale models which used left internal mammary artery(LIMA)and saphenous vein(SVG)as grafts were constructed.Different types of grafts were examined in the models,including normal grafts,grafts with competitive flow and grafts with anastomotic stenosis.Simulation results indicated that comparing with SVG grafts,there was a greater difference between normal LIMA graft and non-patent LIMA graft.Also,the backflow occurred even in LIMA systolic flow.The wall shear stress(WSS)in the graft of the competitive flow LIMA model had an appreciable decrease comparing with the normal graft.In addition,the WSS in the stenosis region of the anastomotic stenosis LIMA model was much higher than its adjacent regions.In contrast,the WSS distributions in the SVG models were much smoother than in the LIMA models.For oscillatory shear index(OSI),there was little difference between normal LIMA and SVG.But when the graft had competitive flow or anastomotic stenosis,much higher OSI occurred in some regions in LIMA than SVG.There are significant differences in hemodynamics between normal grafts and non-patent grafts both in LIMA and SVG.The hemodynamic environment in a normal LIMA is better than that in a normal SVG.However,in the situation of the two types of non-patent grafts,the hemodynamics of SVG is better than LIMA.

关键词： Coronary artery bypass grafting instant patency graft flow hemodynamics multi-scale model

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