Distribution and Properties of Shear Stress in Elastic Beams with Variable Cross Section: Theoretical Analysis and Finite Element Modelling

Man Zhou,Huiyang Fu,Lin An 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.4

It was found that additional shear stress arising from the bending moment should be involved in the formulation due to the effect of variable cross section, which is quite different from the conventional method of analysis for the prismatic members. This paper focuses on the analytical formulation, properties and distribution regularity of the shear stress for the elastic tapered beams with rectangular cross-section. Currently, an analytical expression for the shear stress in elastic tapered beams is derived theoretically based on the theory of elasticity. Most notably, it is strictly proved in mathematics that the additional shear stresses arising from bending moment are self-balanced which only change the distribution of shear stress in the section but will not affect the shear stress resultant. This new finding will be beneficial to promoting the development and consummation of non-prismatic beam theory. The correctness of the theoretical formula have been verified through comparisons with finite element (FE) results of two groups with a total of 12 three-dimensional FE models. The validity of self-balanced properties of additional shear stress in tapered beams under pure bending is additionally verified by using Free Body Cuts in ABAQUS program.

Efficient Regulation of Dyeing Behavior and Physical Properties of Bombyx mori Silks via Graft Polymerization of α-Lipoic Acid

Leilei Wu,Yiwen Ren,Xueming Bao,Ping Wang,Man Zhou,Man Zhou,Qiang Wang 한국섬유공학회 2022 Fibers and polymers Vol.23 No.8

Generally, Bombyx mori silk dyeing is performed using acid dyes. However, the color fastness is alwaysunsatisfactory due to the weak binding forces under neutral conditions. In the present work, graft polymerization of α-lipoicacid (ALA) onto silk fibers was carried out using a two-step method. Briefly, ALA was grafted onto the silk fibers, followedby a reduction-oxidation process to form poly(α-lipoic acid) (PALA) on the fiber surfaces, aiming at improving theelectronegativity of fiber surface and realizing cationic dyeing. The results implied that the combined treatments promotedthe intermolecular crosslinking between fibroin chains, endowing the silk fiber with low zeta potential simultaneously. A thinsedimentary layer on the fiber surfaces was observed for the PALA-deposited silk fibers, companying with a significantincrease in the content of sulfur and O/N ratio, which verified the successful graft polymerization. The modified silk fabricexhibited improved dyeability, and the dyeing depth and color fastness was noticeably higher compared to that of theuntreated after cationic dyeing. Meanwhile, the newly-built intermolecular disulfide crosslinks imparted a detectable antiwrinkleeffect to the silk fabric. This study provides a facile strategy for modification of silk fabric with improved dyeingbehaviors and physical properties.

Lack of Association Between LIG4 Gene Polymorphisms and the Risk of Breast Cancer: A HuGE Review and Meta-analysis

Zhou, Li-Ping,Luan, Hong,Dong, Xi-Hua,Jin, Guo-Jiang,Man, Dong-Liang,Shang, Hong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Objective: Non-homologous end joining (NHEJ) is one of the pathways of repair of DNA double-strand breaks. A number of genes involved in NHEJ have been implicated as breast cancer susceptibility genes such as LIG4. However, some studies have generated conflicting results. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis was to investigate association between LIG4 gene polymorphisms in the NHEJ pathway and breast cancer risk. Methods: Studies focusing on the relationship between LIG4 gene polymorphisms and susceptibility to breast cancer were selected from the Pubmed, Cochrane library, Embase, Web of Science, Springerlink, CNKI and CBM databases. Data were extracted by two independent reviewers and the meta-analysis was performed with Review Manager Version 5.1.6 and STATA Version 12.0 software, calculating odds ratios (ORs) with 95% confidence intervals (95%CIs). Results: According to the inclusion criteria, we final included seven studies with a total of 10,321 breast cancer cases and 10,160 healthy controls in the meta-analysis. The results showed no association between LIG4 gene polymorphisms (rs1805386 T>C, rs1805389 C>T, rs1805388 C>T and rs2232641 A>G) and breast cancer risk, suggesting that the mutant situation of these SNPs neither increased nor decreased the risk for breast cancer. In the subgroup analysis by Hardy-Weinberg equilibrium (HWE) and ethnicity, we also found no associations between the variants of LIG4 gene and breast cancer risk among HWE, non-HWE, Caucasians, Asians and Africans. Conclusion: This meta-analysis suggests that there is a lack of any association between LIG4 gene polymorphisms and the risk of breast cancer.

siRNA Silencing EZH2 Reverses Cisplatin-resistance of Human Non-small Cell Lung and Gastric Cancer Cells

Zhou, Wen,Wang, Jian,Man, Wang-Ying,Zhang, Qing-Wei,Xu, Wen-Gui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Clinical resistance to chemotherapeutic agents is one of the major hindrances in the treatment of human cancers. EHZ2 is involved in drug resistance and is overexpressed in drug-resistant cancer cell lines. In this study, we investigated the effects of EHZ2 on cisplatin -resistance in A549/DDP and AGS/DDP cells. EHZ2 mRNA and protein were found to be significantly overexpressed in A549/DDP and AGS/DDP cells, compared to parental cells. EHZ2 siRNA successfully silenced EHZ2 mRNA and protein expression. Proliferation was inhibited and drug resistance to cisplatin was improved. Flow cytometry showed that silencing of EHZ2 arrested A549/DDP and AGS/DDP cells in the G0/G1 phase, increasing apoptosis, rh-123 fluorescence intensity and caspase-3/8 activities. Silencing of EHZ2 also significantly reduced the mRNA and protein expression levels of cyclin D1 and MDR1,while up-regulating p15, p21, p27 and miR-218 in A549/DPP cells. Furthermore, silencing of EHZ2 also significantly increased the expression level of tumor suppressor factor miR-218. We also found down-regulating EHZ2 expression increased methylation in A549/DDP and AGS/DDP cells. This study demonstrates that drug resistance can be effectively reversed in human cisplatin-resistant lung and gastric cancer cells through delivery of siRNAs targeting EHZ2.

Strength and Mechanism of Carbonated Solidified Clay with Steel Slag Curing Agent

Man Li,Qiang Wang,Jingdong Yang,Xiaoliang Guo,Wenjun Zhou 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.3

Industrial wastes, such as steel slag and desulfurized gypsum, are piled up in large quantities and only a very small portion is recycled, adversely impacting natural ecosystems. Meanwhile, environmental problems caused by CO2 have increasingly received attention. Hence, this study introduces a novel environmentally friendly composite, formed by sodium hydroxide (used as an activator), desulfurized gypsum and steel slag (S-GS). The main objective of this study is to evaluate the potential use of S-GS for solidifying clay under the condition of carbonation curing. Besides, the samples’ characteristics are investigated according to the tests of unconfined compressive strength (UCS), pH, carbonation depth, quality loss and scanning electron microscope (SEM). It is found that the UCS of solidified clay decreases with the increasing water content while it increases first and then decreases with the increasing desulfurized gypsum content, reaching the maximum when the water content is 0.5 times the liquid limit and the content of desulfurized gypsum is 8%. Moreover, compared with the standard curing, carbonation curing can stimulate the activity of S-GS to improve the UCS of samples more effectively. With the increasing carbonation curing time, the mass loss rate and carbonation depth of samples increase while the pH value decreases. Additionally, based on the normalized analysis, the carbonation time has the most significant effect on the UCS. Furthermore, the SEM results indicate that formation of Calcium carbonate and Magnesium carbonate are primary reasons for improving the UCS of the stabilised clay during carbonization. This research promotes steel slag and desulfurized gypsum as green stabilisers for soil stabilization, and the method of carbonation curing contributes to the higher UCS, which also greatly shortens the curing time.

Association Between XRCC5, 6 and 7 Gene Polymorphisms and the Risk of Breast Cancer: A HuGE Review and Meta-analysis

Zhou, Li-Ping,Luan, Hong,Dong, Xi-Hua,Jin, Guo-Jiang,Man, Dong-Liang,Shang, Hong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Objective: Non-homologous end joining (NHEJ) is a pathway for repairing DNA double-strand breaks. Recent publications indicated that XRCC5, XRCC6 and XRCC7 genes may participate in the pathogenesis of breast cancer. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis was to investigate associations between XRCC5, XRCC6 and XRCC7 genetic polymorphisms in the NHEJ pathway and breast cancer risk. Methods: Studies focusing on the relationship between genetic polymorphisms in XRCC5, XRCC6 and XRCC7 genes and susceptibility to breast cancer were selected from the Pubmed, Cochrane library, Embase, Web of Science, Springerlink, CNKI and CBM databases. Data were extracted by two independent reviewers. The meta-analysis was performed with Review Manager Version 5.1.6 and STATA Version 12.0 software. The odds ratio (OR) with 95% confidence interval (95%CI) was calculated based on the extracted data. Results: According to the inclusion criteria, we final included seven studies with a total of 2,864 breast cancer cases and 3,060 healthy controls. Meta-analysis results showed that rs3835 (G>A) and rs828907 (G>T) in XRCC5 gene, and rs132793 (G>A) in XRCC6 gene might increase the risk of breast cancer, while rs132788 G>T and rs6002421 (A>G) might be protective factors. However, there was no relationship between XRCC7 genetic polymorphisms and the risk of breast cancer. Conclusion: This meta-analysis suggests that the rs3835 G>A and rs828907 G>T in XRCC5 gene, rs6002421 (A>G), rs132788 (G>T) and rs132793 (G>A) in XRCC6 gene might be risk factors for breast cancer, while the rs132788 (G>T) and rs6002421 (A>G) in XRCC6 gene might be protective.

Genetic Variants of CYP2D6 Gene and Cancer Risk: A HuGE Systematic Review and Meta-analysis

Zhou, Li-Ping,Luan, Hong,Dong, Xi-Hua,Jin, Guo-Jiang,Man, Dong-Liang,Shang, Hong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Objective: Genetic polymorphisms in metabolic enzymes are associated with numerous cancers. A large number of single nucleotide polymorphisms (SNPs) in the CYP2D6 gene have been reported to associate with cancer susceptibility. However, the results are controversial. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis was to summarize the evidence for associations. Methods: Studies focusing on the relationship between CYP2D6 gene polymorphisms and susceptibility to cancer were selected from the Pubmed, Cochrane library, Embase, Web of Science, Springerlink, CNKI and CBM databases. Data were extracted by two independent reviewers and the meta-analysis was performed with Review Manager Version 5.1.6 and STATA Version 12.0 software. Odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated. Results: According to the inclusion criteria, forty-three studies with a total of 7,009 cancer cases and 9,646 healthy controls, were included in the meta-analysis. The results showed that there was a positive association between heterozygote (GC) of rs1135840 and cancer risk (OR=1.92, 95%CI: 1.14-3.21, P=0.01). In addition, we found that homozygote (CC) of rs1135840 might be a protective factor for cancer (OR=0.58, 95%CI: 0.34-0.97, P=0.04). Similarly, the G allele and G carrier (AG + GG) of rs16947 and heterozygote (A/del) of rs35742686 had negative associations with cancer risk (OR=0.69, 95%CI: 0.48-0.99, P=0.04; OR=0.60, 95%CI: 0.38-0.94, P=0.03; OR=0.50, 95%CI: 0.26-0.95, P=0.03; respectively). Conclusion: This meta-analysis suggests that CYP2D6 gene polymorphisms are involved in the pathogenesis of various cancers. The heterozygote (GC) of rs1135840 in CYP2D6 gene might increase the risk while the homozygote (CC) of rs1135840, G allele and G carrier (AG + GG) of rs16947 and heterozygote (A/del) of rs35742686 might be protective factors.

Preparation of cationic functional polymer poly(Acryloxyethyltrimethyl ammonium chloride)/SiO2 and its adsorption characteristics for heparin

Jiying Men,Jianfeng Guo,Weihong Zhou,Nanyan Dong,Xilun Pang,Baojiao Gao 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.7

Ion-exchange is a widely used purification technology in the heparin manufacturing process. To improve the rate and efficiency, the cationic monomer Acryloxyethyltrimethyl ammonium chloride (DAC) was grafted on silica gel particles by using a surface-initiated graft-polymerization technique, and a novel adsorption polymer of PDAC/SiO2 was prepared. The adsorption experiments of PDAC/SiO2 for heparin show that there are strong electrostatic interactions between heparin with a high density of negative charges and PDAC/SiO2 that exists in many quaternary ammonium cations. Comparing the adsorption kinetics of PDAC/SiO2 with D201 anionic strong alkali exchange resin, PDAC/SiO2 shows higher adsorption capacity and faster adsorption rate. The pH and temperature of solutions have a great influence on the adsorption amount, and there is a maximum adsorption capacity of 121mg/g when pH=7 at 25 oC. The adsorption of PDAC/SiO2 for heparin is an exothermic process and driven by entropy.

Memantine Improves Cognitive Function and Alters Hippocampal and Cortical Proteome in Triple Transgenic Mouse Model of Alzheimer’s Disease

Xinhua Zhou,Liang Wang,Wei Xiao,Zhiyang Su,Chengyou Zheng,Zaijun Zhang,Yu Qiang Wang,Benhong Xu,Xifei Yang,Maggie Pui Man Hoi 한국뇌신경과학회 2019 Experimental Neurobiology Vol.28 No.3

Memantine is a non-competitive N-methyl-D-aspartate receptor (NMDAR) antagonist clinically approved for moderate-to-severe Alzheimer’s disease (AD) to improve cognitive functions. There is no report about the proteomic alterations induced by memantine in AD mouse model yet. In this study, we investigated the protein profiles in the hippocampus and the cerebral cortex of AD-related transgenic mouse model (3×Tg-AD) treated with memantine. Mice (8-month) were treated with memantine (5 mg/kg/bid) for 4 months followed by behavioral and molecular evaluation. Using step-down passive avoidance (SDA) test, novel object recognition (NOR) test and Morris water maze (MWM) test, it was observed that memantine significantly improved learning and memory retention in 3xTg-AD mice. By using quantitative proteomic analysis, 3301 and 3140 proteins in the hippocampus and the cerebral cortex respectively were identified to be associated with AD abnormalities. In the hippocampus, memantine significantly altered the expression levels of 233 proteins, among which PCNT, ATAXIN2, TNIK, and NOL3 were up-regulated, and FLNA, MARK 2 and BRAF were down-regulated. In the cerebral cortex, memantine significantly altered the expression levels of 342 proteins, among which PCNT, PMPCB, CRK, and MBP were up-regulated, and DNM2, BRAF, TAGLN 2 and FRY1 were down-regulated. Further analysis with bioinformatics showed that memantine modulated biological pathways associated with cytoskeleton and ErbB signaling in the hippocampus, and modulated biological pathways associated with axon guidance, ribosome, cytoskeleton, calcium and MAPK signaling in the cerebral cortex. Our data indicate that memantine induces higher levels of proteomic alterations in the cerebral cortex than in the hippocampus, suggesting memantine affects various brain regions in different manners. Our study provides a novel view on the complexity of protein responses induced by memantine in the brain of AD.

Dissipative Analysis for Nonlinear Singular Systems with Time-delay

Juan Zhou,Qing-Ling Zhang,Yue Zhang,Bo Men 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.6

This paper is concerned with the dissipative control problem for a class of nonlinear singular systemswith time-delay. The quadratic supply rate with coefficient matrix Q > 0 and Q 0 are both discussed. Basedon the Lyapunov stability theory, sufficient conditions are given to guarantee that the system is strictly dissipativevia linear matrix inequality technique. Then congruent transformation method and Schur complement lemma arerespectively used to determine corresponding proportional and derivative feedback controller for Q > 0 andQ 0. At last, two examples involve a practical example are given to verify the effectiveness of the method proposed inthis paper.