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Binomial Proportion Estimation in Longitudinal Data with Non-ignorable Non-response

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 623-630页

作者： xue-li wang School of Science Beijing University of Posts and Telecommunications

Non-random missing data poses serious problems in longitudinal studies. The binomial distribution parameter becomes to be unidentifiable without any other auxiliary information or assumption when it suffers from ignorable missing data. Existing methods are mostly based on the log-linear regression model. In this article, a model is proposed for longitudinal data with non-ignorable non-response. It is considered to use the pre-test baseline data to improve the identifiability of the post-test parameter. Furthermore, we derive the identified estimation （IE）, the maximum likelihood estimation （MLE） and its associated variance for the post-test parameter. The simulation study based on the model of this paper shows that the proposed approach gives promising results.

关键词： Binomial proportion information matrix identifiability non-ignorable non-response variance estimation

A Construction of Maximal linearly Independent Array

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Acta Mathematica Sinica,English Series 2010年第7期26卷 1331-1344页

作者： Jun Wu DONG xue li wang College of Mathematics and Econometrics Hu'nan University Changsha 410082 P. R. China College of Mathematics and Information Science Guangzhou University Guangzhou 510006 P. R. China School of Mathematical Sciences South China Normal University Guangzhou 510631 P. R. China

Let M be a subset of r-dimensional vector space Vτ （F2） over a finite field F2, consisting of n nonzero vectors, such that every t vectors of M are linearly independent over F2. Then M is called （n, t）-linearly independent array of length n over Vτ（F2）. The （n, t）-linearly independent array M that has the maximal number of elements is called the maximal （r, t）-linearly independent array, and the maximal number is denoted by M（r, t）. It is an interesting combinatorial structure, which has many applications in cryptography and coding theory. It can be used to construct orthogonal arrays, strong partial balanced designs. It can also be used to design good linear codes, In this paper, we construct a class of maximal （r, t）-linearly independent arrays of length r ＋ 2, and provide some enumerator theorems.

关键词： maximal linearly independent array orthogonal array hamming weight

Polycomb-group （Pc-G） Proteins Control Seed Development in Arabidopsis thaliana L.

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Journal of Integrative Plant Biology 2007年第1期49卷 52-59页

作者： Xiao-xue wang li-Geng Ma National Institute of Biological Sciences Beijing 102206 China

Polycomb-group （Pc-G） proteins repress their target gene expression by assemble complexes in Drosophila and mammals. Three groups of Pc-G genes, controlling seed development, flower development and vernalization response, have been identified in Arabidopsis （Arabidopsis thaliana L.）. MEDEA （MEA）, FERTIliZATION INDEPENDENT SEED2 （FIS2）, and FERTIliZATION INDEPENDENT ENDOSPERM （FIE） are Pc-G genes in Arabidopsis. Their functions in seed development have been extensively explored. The advanced findings of molecular mechanism on how MEA, FIS2 and FIE control seed development in Arabidopsis are reviewed in this paper.

关键词： Arabidopsis FIS1/MEA FIS2 FIS3/FIE Pc-G genes

Effects of body-resistance strengthening and tumor-suppressing granules on immune adhesion function of red blood cells and expression of metastasis protein CD44 in tumor cells of patients with esophageal carcinoma

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World Journal of Gastroenterology 2007年第32期13卷 4360-4364页

作者： Jian-Xiong Zhao xue-Feng li xue-Xi wang Institute of Combined Western and Chinese Traditional Medicine Lanzhou University Medical School Lanzhou 730000 Gansu Province China

AIM： To investigate the effects of Fuzheng Yiliu granules （body-resistance strengthening and tumor-suppressing granules） in patients with esophageal carcinoma. METHODS： We compared the immune adherent properties of red blood cells （RBCs）, the expression of metastasis protein CD44, and the metastasis inhibition factor nm23, in esophageal carcinoma tumor cells of patients before and after radiotherapy in the presence and absence of orally administered Fuzheng Yiliu granules. Sixty-three hospitalized patients with esophageal carcinoma were treated with standard radiotherapy and randomly divided into treatment group （n = 30） treated with both radiotherapy and Fuzheng Yiliu granules and control group （n = 33） given radiotherapy only. Blood samples and tumor tissue were obtained before and after 21 d of treatment. The rosette rates for complement receptor type 3b （C3bRR） and immune complex receptor （ICRR） on RBCs were measured by erythrocyte immunological methods. Expression of CD44 and rim23 in tumor tissue sections was determined by immunohistochemical staining with monoclonal antibodies CD44v6 ad nm23H-1, respectively. RESULTS： The positivity of RBC-C3bRR before and after 21 d of treatment increased from 7.78% ± 1.59% to 10.03% ± 2.01% in the double treatment group, while it changed only slightly from 7.18% ± 1.29% to 7.46% ± 1.12% in the radiotherapy group. The positive rate for RBC-ICRR decreased from 37.68% ± 2.51% to 22.55% ± 1.65% after the double treatment, and from 37.28% ± 2.41% to 24.69% ± 1.91% in radiotherapy group at the same time points. The difference in erythrocyte immune adherent function between the two groups was significant （P 〈 0.01, t-test）. The CD44^± - cases were reduced from 21 （70.00%） to 12 （40.00%） after treatment with Fuzheng Yiliu granules, whereas the CD44^± -cases （69.70%） in the radiotherapy group remained unchanged. The difference between the treatment （40.00%） and control （69.70%） groups was significant （P 〈 0.05）. Although the nm23^±

关键词： Fuzheng Yiliu granule RBC immune function CD44 nm23 Esophageal carcinoma Metastasis protein CD44 controlled clinical trial

Bifurcations of limit Cycles in a Z_4-Equivariant Quintic Planar Vector Field

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Acta Mathematica Sinica,English Series 2010年第4期26卷 779-798页

作者： Yu Hai WU xue Di wang li Xin TIAN Department of Mathematics Jiangsu University Zhenjiang 212013 P. R. China

In this paper, a Z4-equivariant quintic planar vector field is studied. The Hopf bifurcation method and polycycle bifurcation method are combined to study the limit cycles bifurcated from the compounded cycle with 4 hyperbolic saddle points. It is found that this special quintic planar polynomial system has at least four large limit cycles which surround all singular points. By applying the double homoclinic loops bifurcation method and Hopf bifurcation method, we conclude that 28 limit cycles with two different configurations exist in this special planar polynomial system. The results acquired in this paper are useful for studying the weakened 16th Hilbert＇s Problem.

关键词： compounded cycle double homoclinic loops stability bifurcation limit cycles distribution of limit cycles

Coupling Thermomechanical and Microstructural FE Analysis in Plate Rolling Process

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Journal of Iron and Steel Research International 2008年第4期15卷 42-50页

作者： li xue-tong wang Min-ting DU Feng-shan College of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

Using three-dimensional rigid-viscoplastic finite element method （FEM）, a coupling multivariable numerical simulation model for steel plate rolling has been established based on the physical metallurgy microstructural evolution rule and experiential equations. The effects of reduction, deformation temperature, and rolling speed on the deformation parameters and microstructure in plate rolling were investigated using the model. After a typical rolling process of steel plate 16Mn is simulated, the strain, temperature, and microstructure distributions are presented, as well as the ferrite grain transformation during the period of cooling. By comparing the calculated ferrite grain sizes with measured ones, the model is validated.

关键词： hot rolling plate FEM microstructure coupling

EFFECTS OF RAPAMYCIN ON INTRACELLULAR CHOLESTEROL HOMEOSTASIS OF GLOMERULAR MESANGIAL CELL IN THE PRESENCE OF INTERLEUKIN-1β

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Chinese Medical Sciences Journal 2008年第4期23卷 205-211页

作者： Guo-iuan Zhang Hang li xue-wang li Department of Nephrology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms. Methods Intracellular cholesterol accumulation was measured by Oil Red O staining and high performance liquid chromatography. The effects of rapamycin on interleukin-1β（1L-1β）-induced mRNA and protein changes of low-density lipoprotein receptor （LDLR） and ATP-binding cassette transporter Al （ABCAl） were assayed by quantitative real-time PCR and Western blot. Transient expressions of 3 types of mammalian target of rapamycin （mTOR）, including mTOR-WT （wild type）, mTOR-RR （rapamycin resistant, with kinase activity）, and mTOR-RR-KD （rapamycin resistant, without kinase activity）, were obtained by plasmid transfection. Results Rapamycin had no significant influence on intracellular cholesterol concentration trader normal condition, but it significantly decreased the intracellular cholesterol concentration in the presence of IL-1β. Rapamycin dose-dependently suppressed the increased expression of LDLR induced by IL-1β and up-regulated the suppressed expression of ABCAl caused by IL-1β Transient expression of 3 types of mTOR all reduced ABCAl mRNA expression significantly, which all could be overroded by rapamycin. Conclusions Rapamycin may contribute to the maintaining of glomerular mesangial cell intracellular cholesterol homeostasis under inflammatory state by both reducing cholesterol uptake and increasing cholesterol effiux. And the effect may be not completely mediiated by mTOR.

关键词： rapamycin glomerular mesangial cell cholesterol low-density lipoprotein receptor ATP-binding ca, sette transporter A1

lipids-induced Apoptosis Is Aggravated by Acyl-coenzyme A:Cholesterol Acyltransferase Inhibitor

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Chinese Medical Sciences Journal 2010年第2期25卷 76-84页

作者： Jian-ling Tao Xiong-zhong Ruan Hang li xue-mei li xue-wang li Department of Nephrology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China Centre for Nephrology University College London Medical School Royal Free Campus London NW3 2PF UK

Objective To investigate the role of acyl-coenzyme A:cholesterol acyltransferase inhibitor(ACATI) in apoptosis induced by lipids and whether lipids-induced apoptosis is accompanied by increase of free cholesterol in endoplasmic reticulum(ER),in order to further understand the mechanism of lipids-induced apoptosis in advanced *** Human vascular smooth muscle cells(VSMCs) and phorbol 12-myristate 13-acetate(PMA) differentiated THP-1 macrophages were *** thymidine incorporation was applied to detect cell *** was assessed by lactate dehydrogenase(LDH) release.4',6-diamidino-2-phenylindole(DAPI) staining,caspase-3,-7 assay,and Annexin-V/propidium iodide(PI) staining were used to detect *** performance liquid chromatography was used in intracellular free cholesterol and cholesterol ester *** free cholesterol was *** Different lipids had different effects on proliferation and cytotoxicity of VSMCs.25-hydroxycholesterol(25OHC) had biphasic effects on the proliferation of *** low concentration,it stimulated cell proliferation,but turned to proliferation inhibition as concentration reached 15 μg/mL.25OHC and acetylated low density lipoprotein(AcLDL) could respectively induce apoptosis in human VSMCs and PMA differentiated THP-1 macrophages,which was aggravated by ACATI,accompanied by increase of intracellular free cholesterol *** was also an increase of cholesterol content in ER with AcLDL-induced apoptosis in THP-1 *** lipids could induce apoptosis,accompanied by increase of intracellular free cholesterol content,which could be augmented by ACATI,suggesting that insults resulting in ER free cholesterol rise might be the initiator of apoptosis.

关键词： apoptosis atherosclerosis acyl-coenzyme A:cholesterol acyltransferase

Microstructure of Al-Si-Mg alloy with Zr/Hf additions during solidification and solution treatment

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Rare Metals 2019年第11期38卷 1033-1042页

作者： Hui-Lan Huang Zhi-Hong Jia Yuan Xing xue-li wang Qing liu College of Materials Science and Engineering Chongqing University

In this study,the morphology,composition and evolution of intermetallics in Al-7Si-0.3Mg,Al-7Si-0.3Mg-0.47Hf,Al-7Si-0.3Mg-0.16 Zr and Al-7Si-0.3Mg-0.14Zr-0.44Hf alloys were characterized by optical microscope(OM),scanning electron microscope(SEM)with energy-dispersive spectrometer(EDS) and transmission electron microscope(TEM).The AlSiZr,AlSiHf and AlSiZrHf phases are formed with additions of Zr and/or Hf in base alloy during solidification,especially the AlZrHf primary *** three-dimensional morphology of the AlZrHf particle evolves from 10-polyhedron-like to compressed cube-like during *** new AlZrHf phase experiences partial dissolution after solution treatment,while the others remain in the initial *** Si contents lead to form thermally stable Zr/Hfrich precipitates in Zr/Hf-containing alloys during solution treatment,especially the nanobelt-like Si2Zr,Si2Hf and Si2(Zr,Hf) *** orientation relationships and the growth mechanism are *** finding of the work broadens the elevated temperature application of Al-Si-Mg in modern automotive aluminum engine.

关键词： Al-Si-Mg cast alloy Primary phase Solution treatment Precipitate Orientation relationships