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一种改进的半参数极大似然法估计量的渐近性质

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数学学报（中文版） 2005年第2期48卷 391-396页

作者：余歧青黄毓清美国纽约州立大学美国纽约STRANG癌症防治中心

本文研究线性回归模型, y=β'X+∈,并假设y可被右删失,∈的分布函数F0未知.本文证明,在某些条件下, β的一种改进的半参数极大似然法估计量β 有相合性. 同时证明,如果F0不连续,则P{β≠βi.o.}=0.这意味着以概率为一, 当样本很大时, ... 详细信息

本文研究线性回归模型, y=β'X+∈,并假设y可被右删失,∈的分布函数F0未知.本文证明,在某些条件下, β的一种改进的半参数极大似然法估计量β 有相合性. 同时证明,如果F0不连续,则P{β≠βi.o.}=0.这意味着以概率为一, 当样本很大时, β=β.文献中的现有估计量未见有关于这一性质的报道.相反,包括 Buckley-James估计量及M-估计量在内的大多数的估计量,都不满足这一性质.

关键词：相合性超优效性半参极大似然法估计量

增强cT和急性肾损伤：根据糖尿病状态和肾功能进行的风险分层

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国际医学放射学杂志 2023年第4期 486-486页

作者： c.c.Lee y.L.chan y.c.wong c.J.Ng c.H.chang c.c.Hung 崔倩

摘要糖尿病可能与cT对比剂诱导的急性肾损伤（cIAKI）的增加有关，但目前尚无在有/无肾功能障碍的大样本中的研究。目的研究糖尿病状态和估计肾小球滤过率

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静脉注射cT对比剂与急性肾损伤：一项基于急诊多中心的研究

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国际医学放射学杂志 2022年第1期 110-110页

作者： T.H.Su c.H.Hsieh y.L.chan y.c.wong c.F.Kuo c.H.Li 白雪

摘要尽管静脉注射对比剂后发生急性肾损伤（AKI）的风险可能被夸大，但肾功能受损病人的风险仍值得关注。目的探讨与接受cT平扫的病人相比，静脉注射对比剂的病人

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Asymptotic Properties of a Modified Semi-Parametric MLE in Linear Regression with Right-censored Data

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Acta Mathematica Sinica,English Series 2002年第2期18卷 405-416页

作者： wong George y.c. Strang cancer Prevention center.428 E 72nd Street.New york.Ny 10021.USA

consider a linear regression model y=β'X+*** y may be right censored and the cdf F+o of e is *** show that a modified semi-parametric *** by .is strongly consistent under certain regularity *** F_o is discontinuous,then P(≠βi.o.)=0, which means that P(=βif the sample size is large)=*** latter property has not been reported for the existing *** contrast,most estimators,such as the Buckley-James estimator and M-estimators .satisfy that P(≠βi.o.)=1.

关键词： consistency Super-efficiency Semi-parametric MLE

Mechanosynthesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide catalysts for the partial oxidation of n-butane to maleic anhydride

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Journal of Natural Gas chemistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-yap y.c. wong y. Kamiya W.J. Tang Putra center for catalysis Science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate School of Environmental Science Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.

关键词： mechanosynthesis mechanochemical treatment bismuth vanadyl pyrophosphate

Nitric oxide removal by wastewater bacteria in a biotrickling filter

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Journal of Environmental Sciences 2014年第3期26卷 555-565页

作者： Hejingying Niu Dennis y c Leung chifat wong Tong Zhang Mayngor chan Fred c c Leung Department of Mechanical Engineering The University of Hong Kong School of Biological Sciences The University of Hong Kong Department of civil Engineering The University of Hong Kong

Nitric oxide （NO） is one of the most important air pollutants in atmosphere mainly emitted from combustion source. A biotriclding filter was designed and operated to remove NO from an air stream using bacteria extracted from the sewage sludge of a municipal sewage treatment plant. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments （L9（34）） were designed. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter and has a significant negative effect on the system. The optimal conditions of the biotrickling filter occurred at a temperature of 40℃, a pH of 8.0 and a chemical oxygen demand of 165 mg/L in the recycled water with no oxygen in the system. The bacteria sample was detected by DNA sequencing technology and showed 93%-98% similarity to Pseudomonas mendocina. Moreover, a full gene sequencing results indicated the bacterium was a brand new strain and named as P. mendocina DLHK. This strain can transfer nitrate to organic nitrogen. The result suggested the assimilation nitrogen process in this system. Through the isotope experimental analysis, two intermediate products （^15NO and ^15N2O） were found. The results indicated the denitrification function and capability of the biotrickling filter in removing NO.

关键词： NO reduction biotrickling filter orthogonal experiment Pseudomonas mendocina isotope labeling

End Effect on the Twin-Wire Depth Probe

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Journal of Thermal Science 1992年第4期1卷 286-291页

作者： c.y.Liu y.W.wong 等 SchoolofMechanicalandProductionEngineering NanyangTechnologicalInstituteNayangAvenueSingapre2263 Sc

The end effect on the output voltage of a twin-wire depth probe was investigated both theoretically and ex- *** was found that the contribution of the end of the probe to the output voltage depends upon the distance between the boundary and the end of the probe and the geometrical configuration of the probe. By mounting a piece of plate to the end of the electrodes,the end effect can be ***,the size of the plate required to eliminate completely this effect is much larger than that usually mounted on commercially available *** between theoretical and experimental results was *** agreement was obtained.

关键词： twin-wire probe depth probe

On Systems of Boundary Value Problems for Differential Inclusions

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Acta Mathematica Sinica,English Series 2007年第3期23卷 549-556页

作者： Lynn ERBE christopher c.TISDELL Patricia J.y.wong Department of Mathematics The University of Nebraska-LincolnLincolnNE 68588-0130USA School of Mathematics and Statistics The University of New South WalesSydney 2052Australia School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyan9 AvenueSingapore 639798Singapore

Herein we consider the existence of solutions to second-order, two-point boundary value problems （BVPs） for systems of ordinary differential inclusions. Some new Bernstein-Nagumo conditions are presented that ensure a priori bounds on the derivative of solutions to the differential inclusion. These a priori bound results are then applied, in conjunction with appropriate topological methods, to prove some new existence theorems for solutions to systems of BVPs for differential inclusions. The new conditions allow of the treatment of systems of BVPs without growth restrictions.

关键词： boundary value problem, systems of differential inclusions, existence of solutions a priori bounds Bernstein-Nagumo condition

Effects of polydimethylsiloxane membrane surface treatments on human uterine smooth muscle cell strain response

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Bioactive Materials 2024年第2期32卷 415-426页

作者： Elizabeth E.Marr Brett c.Isenberg Joyce y.wong Boston University Division of Materials Science and EngineeringUnited States charles Stark Draper Laboratory Bioengineering DivisionUnited States Boston University Department of Biomedical EngineeringUnited States

In the United States,1 in 10 infants are born *** majority of neonatal deaths and nearly a third of infant deaths are linked to preterm *** birth is initiated when the quiescent state of the uterus ends prematurely,leading to contractions and parturition beginning as early as 32 weeks,though the origins are not well *** enable research and discovery of therapeutics with potential to better address preterm birth,the capability to study isolated cell processes of pregnant uterine tissue in vitro is *** development of an in vitro model of the myometrium utilizing human uterine smooth muscle cells(uSMcs)responsible for contractions provides a methodology to examine cellular mechanisms of late-stage pregnancy potentially involved in preterm *** discuss culture of uSMcs on a flexible polydimethylsiloxane(PDMS)substrate functionalized with cationic poly-L-lysine(PLL),followed by extracellular matrix(EcM)protein *** work exploring uSMc behavior on PDMS substrates have utilized collagen-I coatings,however,we demonstrated the first exploration of human uSMc response to strain on fibronectin-coated flexible membranes,importantly reflecting the significant increase of fibronectin content found in the myometrial EcM during late-stage *** the model we developed,we conducted proof-of-concept studies to investigate the impact of substrate strain on uSMc cell morphology and gene *** was found that PLL and varied EcM protein coatings(collagen I,collagen III,and fibronectin)altered cell nuclei morphology and density on PDMS ***,varied strain rates applied to uSMc substrates significantly impacted uSMc gene expression of IL-6,a cytokine associated with instances of preterm *** results suggest that both surface and mechanical properties of in vitro systems impact primary human uSMc phenotype and offer uSMc culture methodologies that can be utilized to further the understanding of cellu

关键词： Uterine Myometrium Bioengineered in vitro models Strain Pregnancy Nuclei Interleukin 6 Preterm labor