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Stable reflexive sheaves over compact Gauduchon manifolds

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Science China Mathematics 2024年

作者： Zeng Chen Chuanjing zhang School of Mathematical Sciences University of Science and Technology of China School of Mathematics and Statistics Ningbo University

In this paper, we obtain the Hermitian-Einstein metrics on stable reflexive sheaves over compact Gauduchon manifolds.

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食管癌三维适形放射治疗疗效观察

新疆医科大学学报 2005年第7期28卷 649-651页

作者：王义海张新春张瑾熔王海峰葛峰新疆医科大学附属肿瘤医院放疗二科新疆乌鲁木齐83011

目的:探讨三维适形放射治疗(3DCRT)食管癌的近期疗效及放射治疗反应。方法:75例经病理证实的食管癌患者,分为常规放疗组(CF组)和三维适形放射治疗组(3DCRT组)。其中CF组40例,3DCRT组35例。CF组:2GY/次,5次/周,总剂量60-66Gy.7周内完成;3... 详细信息

目的:探讨三维适形放射治疗(3DCRT)食管癌的近期疗效及放射治疗反应。方法:75例经病理证实的食管癌患者,分为常规放疗组(CF组)和三维适形放射治疗组(3DCRT组)。其中CF组40例,3DCRT组35例。CF组:2GY/次,5次/周,总剂量60-66Gy.7周内完成;3DCRT组:先常规放疗20GY,方法同CF组.然后改用三维适形放疗,2Gy/次,5次/周,总剂量60-66Gy,7周内完成。以放疗结束时临床症状及放疗结束后3个月的食管钡餐片作为评价依据。结果:CF组和3DCRT组的有效率(CR+PR)分别为85%、100N,两组比较差异有统计学意义(x2=3.85,P0.05),两组比较放射性气管炎发生率差异无统计学意义(X2=3.24,P>0.05)。结论:三维适形放射治疗能明显提高食管癌的近期疗效,放射性毒性可耐受。

关键词：食管肿瘤/放射疗法放射疗法食管癌

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Ding Projective Modules and Dimensions over Formal Triangular Matrix Rings

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Journal of Mathematical Research with Applications 2024年第5期 617-632页

作者： Wenhui zhang Ting LIU Department of Mathematics and Statistics Northwest Normal University

Let T be a formal triangular matrix ring. We prove that, if for each 1 ≤ j < i ≤ n, Uijis flat on both sides, then a left T-module ■ is Ding projective if and only if M1is a Ding projective left A1-module and for each 1 ≤ k ≤ n-1 the mapping Фk+1,k : Uk+1,k■AkMk→Mk+1is injective with cokernel Ding projective over Ak+1. As a consequence, we describe Ding projective dimension of a left T-module.

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Synthesis of highly stable Ni nanoparticles via electrostatic self-assembly for enhanced hydrogen storage of MgH2

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Rare Metals 2024年第9期43卷 4356-4366页

作者： Qin-Ke Tang Jiang-Chuan Liu Rui Shi Yun-Feng Zhu Ji-Guang zhang Ya-Na Liu Jun Wang Yao zhang Xiao-Hui Hu Zhi-Bin Liu Li-Quan Li College of Materials Science and Engineering Jiangsu Collaborative Innovation Centre for Advanced Inorganic Function CompositesNanjing Tech University School of Materials Science and Engineering Southeast University

Magnesium-based hydrides have been widely recognized as an appropriate choice for solid-state hydrogen ***,its undesirable thermodynamics and sluggish hydrogenation/dehydrogenation kinetics are major bottlenecks for its ***,a highly stable and highly dispersed Ni-based catalyst （Ni/Al2O3/GN） was fabricated to promote the hydrogen storage performance of MgH2via the electrostatic effect of NiAl-LDH/GN precursor with a co-calcination reduction ***2-5wt % Ni/Al2O3/GN exhibits excellent hydrogen storage performance,releasing about 5.7 wt % hydrogen in 3500 s at 250℃,and can reach a saturation hydrogen absorption of about 6.15 wt% in 3000 s at 100℃.Furthermore,it also shows low dehydrogenation apparent activation energy of 89.1 and 118.2 kJ·***,the catalyst ensures the stability of both the physical phase and structure during ball milling and cycling *** role of each phase in Ni/Al2O3/GN on the hydrogen storage performance of MgH2was also discussed through experiments and theoretical calculation,and the synergistic catalytic mechanism of Ni/Al2O3/GN was clearly *** work provides a unique perspective for the preparation of highly stable and highly dispersible catalysts.

关键词： Catalytic mechanism Hydrogen storage performance Magnesium hydride Ni/Al2O3/GN

Model-averaging-based semiparametric modeling for conditional quantile prediction

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Science China Mathematics 2024年

作者： Chaohui Guo Wenyang zhang School of Mathematical Sciences Chongqing Normal University Department of Mathematics University of York

In real data analysis, the underlying model is frequently unknown. Hence, the modeling strategy plays a key role in the success of data analysis. Inspired by the idea of model averaging, we propose a novel semiparametric modeling strategy for the conditional quantile prediction, without assuming that the underlying model is any specific parametric or semiparametric model. Due to the optimality of the weights selected by leaveone-out cross-validation, the proposed modeling strategy provides a more precise prediction than those based on some commonly used semiparametric models such as the varying coefficient and additive models. Asymptotic properties are established in the proposed modeling strategy along with its estimation procedure. We conducted extensive simulations to compare our method with alternatives across various scenarios. The results show that our method provides more accurate predictions. Finally, we applied our approach to the Boston housing data,yielding more precise quantile predictions of house prices compared with commonly used methods, and thus offering a clearer picture of the Boston housing market.

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全容积表观扩散系数直方图鉴别低级别膀胱癌与结节型腺性膀胱炎的价值

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中华放射学杂志 2024年第4期58卷 448-451页

作者：黎如春张孝先海梦璐黎海亮郑州大学附属肿瘤医院、河南省肿瘤医院放射科郑州450008

回顾性分析2016年1月至2021年12月郑州大学附属肿瘤医院收治的62例低级别膀胱癌和28例结节型腺性膀胱炎(CG)患者的临床及扩散加权成像(DWI)资料,经MATLAB分析获得全容积表观扩散系数(ADC)直方图参数,采用Mann-Whitney U检验比较2组间差... 详细信息

回顾性分析2016年1月至2021年12月郑州大学附属肿瘤医院收治的62例低级别膀胱癌和28例结节型腺性膀胱炎(CG)患者的临床及扩散加权成像(DWI)资料,经MATLAB分析获得全容积表观扩散系数(ADC)直方图参数,采用Mann-Whitney U检验比较2组间差异,采用受试者操作特征曲线评估各参数鉴别低级别膀胱癌和结节型CG的效能。低级别膀胱癌与结节型腺性膀胱炎间第5、25、50、75、95百分位数ADC、最大ADC、平均ADC、偏度差异有统计学意义(P<0.05),第50百分位数ADC的曲线下面积最高,为0.727(95%CI 0.623~0.816),灵敏度为0.565,特异度为0.929。

关键词：磁共振成像膀胱肿瘤腺性膀胱炎表观扩散系数直方图

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The inhomogeneous incompressible Hall-MHD system with only bounded density

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Science China Mathematics 2024年

作者： Jin Tan Lan zhang Laboratoire de Math′ematiques AGM UMR CNRS 8088 Cergy Paris Universit′e Center for Mathematical Sciences and Department of Mathematics Wuhan University of Technology

This paper is dedicated to the global-in-time existence and uniqueness issues of solutions for the inhomogeneous incompressible Hall-magnetohydrodynamics(MHD) system with merely bounded density. In a three-dimensional case, assuming that the initial density is a small perturbation of a positive constant in the L∞norm, we prove global well-posedness for small initial velocity and magnetic fields in critical Besov spaces. Next, we consider the so-called 21/2D flows for the inhomogeneous Hall-MHD system(that is 3D flows independent of the vertical variable) and establish the global existence of strong solutions by only assuming that the initial magnetic field is small in critical spaces and the initial density is bounded and bounded away from zero. In particular, those solutions allow piecewise constant density with jumps so that a mixture of fluids can be considered. Compared with inhomogeneous incompressible Navier-Stokes equations, the new difficulties of proving these results come from the additional so-called Hall term, which endows the magnetic equation with a quasi-linear character. In order to overcome them, we reformulate the system by taking advantage of the curl form of the magnetic equation and develop some new maximal regularity estimates for the Stokes system with just bounded coefficients.

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The moment map for the variety of associative algebras

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Science China Mathematics 2024年

作者： Hui zhang Zaili Yan School of Mathematics Southeast University School of Mathematics and Statistics Ningbo University

We consider the moment map m:PV_n→iu（n） for the action of GL（n） on Vn=?2（C~n）*?C~n,and study the critical points of the functional ■:PVn→***,we prove that[μ]∈PV_n is a critical point if and only if Mμ=cμI+Dμfor some cμ∈R and Dμ∈Der（μ）,where ■.Then we show that any algebraμadmits a Nikolayevsky derivation?μwhich is unique up to automorphism,and if moreover,[μ]is a critical point of Fn,then■ .Secondly,we characterize the maxima and minimatof the functional F_n:A_n→R,where An denotes the projectivization of the algebraic varieties of all the n-dimensional associative ***,for an arbitrary critical point[μ]of F_n:A_n→R,we obtain a description of the algebraic structure ofμ.Finally,we classify the critical points of F_n:A_n→R for n=2and n=3,respectively.

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微藻生物肥提高谷子对氮磷胁迫的耐受性

植物营养与肥料学报 2024年第6期30卷 1130-1141页

作者：李慧敏李炯珊张克燕张春辉季春丽王计平李润植山西农业大学农学院/分子农业与生物能源研究所/山西省特用作物遗传和代谢工程研究中心山西晋中030801

【目的】氮磷营养缺乏是作物生长发育的重要限制因素。微藻生物肥是由单细胞光合藻类生物质构成的一种新型肥料,其促进作物生长和改良土壤肥力的功效备受关注。本研究旨在解析微藻生物肥对谷子(Setaria italica L.)生长的促进作用,特别... 详细信息

【目的】氮磷营养缺乏是作物生长发育的重要限制因素。微藻生物肥是由单细胞光合藻类生物质构成的一种新型肥料,其促进作物生长和改良土壤肥力的功效备受关注。本研究旨在解析微藻生物肥对谷子(Setaria italica L.)生长的促进作用,特别是提高谷子对氮磷缺乏的耐受性的生物学功能,为微藻生物肥在谷子等作物的化肥减量和绿色可持续生产的应用提供理论支撑。【方法】供试谷子品种为‘晋谷21’。采用水培试验,设置正常氮磷(霍格兰标准营养液中氮和磷含量分别为210和71 mg/L)、无氮磷(营养液中氮和磷含量均为0 mg/L)和1/2氮磷(营养液中氮和磷含量分别为105和35.5 mg/L)3个氮磷水平。制备小球藻(Chlorella ***01)(DT)、埃氏小球藻(Chlorella emersonii)(AS)和蛋白核小球藻(Chlorella pyrenoidosa)(DB)3种微藻生物肥,分别与3个氮磷处理液等比混合,共构成9个处理,每个氮磷水平下设置1个不添加微藻微生物溶液处理为对照。在谷子幼苗生长至两叶一心时,将其移入处理液中,在温室条件下连续培养9天,期间每3天补充1次处理液。处理结束时,测定各处理谷子幼苗的生长指标、生物量、色素含量、光合活性和氮磷含量等生理生化参数,并通过qRT-PCR技术分析氮磷转运蛋白相关基因(SiNRT1.11、SiNRT2.1、SiPHT1.2和SiPHT1.1)的表达谱。【结果】与正常氮磷处理相比,无氮磷和1/2氮磷处理均显著降低了谷子幼苗生物量、光合色素(叶绿素a,b和类葫萝卜素)含量和光合作用。在3种剂量氮磷处理下,施用3种微藻生物肥处理均显著提高谷子幼苗鲜重和干重、光合色素含量(特别是类胡萝卜素)和光合作用参数[实际光化学效率Y(II),光化学淬灭系数qP和非光化学淬灭系数NPQ]。此外,微藻生物肥还显著增加了谷子幼苗全氮和全磷含量。微藻生物肥DT处理的促生效应最显著。qRT-PCR检测谷子幼苗氮磷转运相关基因表达显示,微藻生物肥DT处理显著上调谷子幼苗地上部硝酸盐转运蛋白基因SiNRT1.11和根系硝酸盐转运蛋白基因SiNRT2.1的表达,以及根系中磷酸盐转运蛋白基因SiPHT1.2和SiPHT1.1的表达。【结论】施用微藻生物肥能显著提高谷子幼苗地上部硝酸盐转运蛋白基因SiNRT1.11和根系硝酸盐转运蛋白基因SiNRT2.1,以及根系中磷酸盐转运蛋白基因SiPHT1.2和SiPHT1.1的表达,进而改善谷子幼苗生长和光合生理特性,提高谷子对氮磷胁迫的抗性。

关键词：谷子(Setaria italica L.) 微藻生物肥氮磷缺乏生理生化特性基因表达

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