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Optimal design of vibration absorber using minimax criterion with simplified constraints

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Acta Mechanica Sinica 2012年第3期28卷 848-853页

作者： Jie fang shi-min wang Qi wang School of Aeronautics Science and Engineering Beihang University100191 BeijingChina

In this paper, a minimax design of damped dynamic vibration absorber for a damped primary system is investigated to minimize the vibration magnitude peaks. Moreover, to reduce the sensitivity of the primary system response to variations of the forcing frequency for a two- degree-of-freedom system, the primary system should have two equal resonance magnitude peaks. To meet this re- quirement, a set of simplified constraint equations includ- ing distribution characteristics of the resonant frequencies of the primary system is established for the minimax objective function. The modified constraint equations have less un- known variables than those by other authors, which not only simplifies the computation but also improves the accuracy of the optimal values. The advantage of the proposed method is illustrated through numerical simulations.

关键词： minimax Optimization Dynamic vibrationabsorber (DVA) Sensitivity

Synthesis and photocatalytic activity of TiO_2/conjugated polymer complex nanoparticles

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Chinese Chemical Letters 2008年第6期19卷 742-746页

作者： shi xiong min fang wang Lei Feng Yong Chun Tong Zi Rong Yang Department of Chemistry Key Laboratory of Resources and Environmental Chemistry of West China Hexi University Zhangye 734000 China

A photocatalyst of nanometer TiO2/conjugated polymer complex was successfully synthesized and characterized by spectroscopic methods and photocatalytic experiments. The complex photocatalyst could be activated by absorbing both ultraviolet and visible light （λ = 190-800 nm）. Methylene blue （MB） could be degraded more efficiently on the complex photocatalyst than on the TiO2 under natural light. The conjugated polymer played a promoting role in the photocatalytic degradation of MB. The calcination temperature had an important effect in degradation of dye and could be summarized as 260℃ 〉 300 ℃ 〉 340 ℃ 〉 220 ℃ 〉 180 ℃.

关键词： TiO2 Conjugated polymer Complex photocatalyst Methylene blue Degradation Natural light

Inference for accelerated bivariate dependent competing risks model based on Archimedean copulas under progressive censoring

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Applied Mathematics(A Journal of Chinese Universities) 2023年第4期38卷 475-492页

作者： ZHANG Chun-fang shi Yi-min wang Liang School of Mathematics and Statistics Xidian UniversityXi'an 710126China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China School of Mathematics Yunnan Normal UniversityKunming 650500China

Dependent competing risks model is a practical model in the analysis of lifetime and failure *** dependence can be captured using a statistical tool to explore the re-lationship among failure *** this paper,an Archimedean copula is chosen to describe the dependence in a constant-stress accelerated life *** study the Archimedean copula based dependent competing risks model using parametric and nonparametric *** parametric likelihood inference is presented by deriving the general expression of likelihood function based on assumed survival Archimedean copula associated with the model parameter *** the nonparametric estimation with progressive censoring and the non-parametric copula estimation,we introduce a nonparametric reliability estimation method given competing risks data.A simulation study and a real data analysis are conducted to show the performance of the estimation methods.

关键词： dependent competing risks model accelerated life tests Archimedean copula nonparametric reliability estimation

Mei Symmetry and Conserved Ouantity of Tzénoff Equations for Nonholonomic Systems of Non-Chetaev's Type

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Communications in Theoretical Physics 2008年第4期49卷 851-854页

作者： ZHENG shi-wang XIE Jia-fang LI Yan-min Department of Physics and Information Engineering Shangqiu Teachers College Shangqiu 476000 China Department of Mechanics Beijing Institute of Technology Beijing 100081 China

Mei symmetry of Tzenoff equations for nonholonomic systems of non-Chetaev＇s type under the infinitesimal transformations of groups is studied. Its definitions and discriminant equations of Mei symmetry are given. Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given. Hojman conserved quantity of Tzenoff equations for the systems through Lie symmetry in the condition of special Mei symmetry is obtained.

关键词： nonholonomic system Tzenoff equations Mei symmetry conserved quantity

Novel mutation in the SALL1 gene in a four-generation Chinese family with uraemia:A case report

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World Journal of Clinical Cases 2022年第20期10卷 7068-7075页

作者： Jia-Xi fang Jin-shi Zhang min-min wang Lin Liu Department of Nephrology Zhejiang Provincial People’s HospitalAffiliated People’s HospitalHangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Department of Nephrology Chinese Medical Nephrology Key Laboratory of Zhejiang ProvinceHangzhou 310014Zhejiang ProvinceChina Department of Nephrology Zhejiang Provincial People’s HospitalQingdao UniversityHangzhou 310014Zhejiang ProvinceChina School of Medicine Hangzhou Normal UniversityHangzhou 310018Zhejiang ProvinceChina

BACKGROUND Approximately 10%of adults and nearly all children who receive renal replacement therapy have inherited risk factors or are related to genetic *** the past,due to the limitations of detection technology and the nonspecific manifestations of uraemia,the etiological diagnosis is *** addition to common monogenic diseases and complex disorders,advanced testing techniques have led to the recognition of more hereditary renal ***,we report a four-generation Chinese family in which four individuals had a novel SALL1 mutation and presented with uraemia or abnormal urine *** SUMMARY A 32-year-old man presented with end-stage renal disease with a 4-year history of *** father and paternal aunt both had a history of unexplained renal failure with haemodialysis,and his 10-year-old daughter presented with *** patient had multiple congenital abnormalities,including bilateral overlapping toes,unilateral dysplastic external ears,and sensorineural hearing *** family members also presented with similar *** testing revealed that the proband carried a novel heterozygous shift mutation in SALL1_exon 2(c.3437delG),and Sanger sequencing confirmed the same mutation in all affected family *** We report a novel SALL1 exon 2(c.3437delG)mutation and clinical syndrome with kidney disease,bilateral overlapping toes,unilateral dysplastic external ears,and sensorineural hearing loss in a four-generation Chinese family.

关键词： SALL1 Gene mutation Uraemia Hereditary renal diseases End stage renal disease Case report

Cell-specific expression and immunolocalization of nitric oxide synthase isoforms and the related nitric oxide/cyclic GMP signaling pathway in the ovaries of neonatal and immature rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第1期12卷 55-64页

作者： Wei ZHANG Quan-wei WEI Zheng-chao wang Wei DING Wei wang fang-xiong shi Laboratory of Animal Reproduction College of Animal Science and Technology Nanjing Agricultural University Nanjing 210095 China

Objective: The present study is designed to investigate the cellular expressions and immunolocalizations of three different nitric oxide synthase (NOS) isoforms and the related nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the ovaries of neonatal and immature ***: The ovaries were obtained from ICR (Institute for Cancer Research) female Sprague-Dawley rats at postnatal days 1,5,7,10,and *** we carried out the histologic examination,immunohistochemistry,measurement of NOS activity,and modifications within the NO/cGMP ***: During postnatal days 1,5,7,10,and 19,all three isoforms of NOS were mainly localized to the oocytes and expressed as a gradual increase in granulosa cells and theca cells within the growing *** ovarian total NOS activities and NO levels were increased at postnatal days 7 and 10 compared with other ***: Our findings suggest that the locally produced NO and the NO/NOS signaling systems are involved in the follicular development to puberty.

关键词： Nitric oxide synthase Nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway Ovary Neonatal rats Prepuberty

Epigenetics effect on pathogenesis of thyroid-associated ophthalmopathy

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1441-1448页

作者： Jia-min Cao Nuo wang shi-Ying Hou Xin Qi Wei xiong Department of Ophthalmology Third Xiangya HospitalCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Ophthalmology Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

Thyroid-associated ophthalmopathy(TAO)is an autoimmune *** studies have found the aberrant epigenetics in TAO,including DNA methylation,noncoding RNAs,and histone *** genes have an aberrant level of methylation in *** example,higher levels are found in CD14,MBP,ANGLE1,LYAR and lower levels in DRD4 and ***-coding RNAs are involved in the immune response(miR-146a,miR-155,miR-96,miR-183),fibrosis regulation(miR-146a,miR-21,miR-29),adipogenesis(miR-27)and are thought to play roles in *** is also related to the clinical activity score(miR-Let7d-5p)and may be a predictor of glucocorticoid therapy(miR-224-5p).The quantities of H4 in TAO are increased compared with euthyroid control subjects,and the role of histone modifications in Graves*disease may lead to better understanding of its role in *** studies are needed to explain the role of epigenetics in TAO and provide potential therapeutic strategies.

关键词： thyroid-associated ophthalmopathy epigenetics DNA methylation non-coding RNA histone modification

The COI1 and DFR Genes are Essential for Regulation of Jasmonate-lnduced Anthocyanin Accumulation in Arabidopsis

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Journal of Integrative Plant Biology 2007年第9期49卷 1370-1377页

作者： Qin-fang Chen Liang-Ying Dai shi Xiao Yun-Sheng wang xiong-Lun Liu Guo-Liang wang Department of Plant Pathology College of Bio-Safety Science & Technology Hunan Agricultural University Changsha 410128 China Rice Functional Genomics Laboratory Hunan Agricultural University Changsha 410128 China Department of Plant Pathology Ohio State University Columbus OH 43210 USA

Jasmonates （JAs） are a class of plant hormones that play important roles in the regulation of plant development and plant defense. It has been shown that Arabidopsis plants produce much higher levels of anthocyanins when treated exogenously with methyl jasmonate （MeJA）. However, a molecular link between the JA response and anthocyanin production has not been determined. The CORONATINE INSENTITIVE1 （COI1） gene is a key player in the regulation of many JA-related responses. In the present study, we demonstrate that the COI1 gene is also required for the JA-induced accumulation of anthocyanins in Arabidopsis. Furthermore, the MeJA-inducible expression of DIHYDROFLAVONOL REDUCTASE （DFR）, an essential component in the anthocyanin biosynthesis pathway, was completely eliminated in the coil mutant. Jasmonateinduced anthocyanin accumulation was found to be independent of auxin signaling. The present results indicate that the expression of both COI1 and DFR genes is required for the regulation of JA-induced anthocyanin accumulation and that DFR may be a key downstream regulator for this process.

关键词： anthocyanin Arabidopsis, COI1 DFR jasmonates.

Ultrafast Optical Properties of C_(70) Thin Film

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Chinese Physics Letters 1996年第9期13卷 668-671页

作者： wang Cong-fang AXi-cheng XIA Zong-ju ZOU Ying-hua QIAN Jiang QIAN shi-xiong Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 Department of Physics fudan UniversityShanghai 200433

The relaxation of optically excited carrier in C_(70) thin film fabricated by physical jet deposition was investigated by femtosecond pump-probe measurements.A transient decrease in transmission was observed indicating induced *** comparison to C_(60) thin film the initial response of C_(70) film is laser pulse limited and the long lived component has smaller *** third order optical nonlinear susceptibility of C_(70) thin film was determined to be χ^((3))=3.3×10^(-11) esu by femtosecond time-resolved optical Kerr *** the primarily pulse limited response the dephasing time of C_(70) thin film has been proved to be shorter than the laser pulse width.

关键词： pulse pump film