80 results on '"Qing-Shan Yang"'
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2. Numerical simulation of macrosegregation phenomenon in Cu-6wt%Ag alloy ingots fabricated by electromagnetic stirring
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Qing-shan Yang, Jian-xu Duan, An-yuan Deng, and En-gang Wang
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Numerical simulation ,Cu-6wt%Ag alloy ,Electromagnetic stirring ,Macrosegregation ,Large cross-section ingot ,Segregation degree ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The development and research of high strength and conductivity materials are essential for the advancement of high-field magnets, including pulsed magnets. This study investigates the effect of electromagnetic fields on the solidification casting of binary Cu-6wt%Ag alloy ingots with diameters of 40 and 160 mm. A 3D numerical simulation is performed utilizing the continuum model with conservation of total momentum, mass, energy, and species. The results indicate that applying electromagnetic stirring (EMS) to small cross-section ingots can cause many randomly distributed small regions with higher segregation degrees inside the ingot, which is not conducive to improving the macrosegregation inside the ingot. For large cross-section ingots without EMS, compared to small cross-section ingots, there is more severe macrosegregation inside the ingot, especially the extreme center segregation with a maximum segregation degree of about 414%. EMS can effectively control macrosegregation within a specific range and eliminate center segregation. When the linear EMS's magnetic induction intensity is set to 0.06 T, the maximum segregation degree near the ingot center can be reduced to less than 260%. Simultaneously, the EMS induced forced convection is also instability, leading to numerous haphazard solute accumulations and depletions, which explains many small segregation regions in the ingot. In terms of improving macrosegregation in large cross-section ingots, Linear EMS has a definite advantage over rotary EMS. It is possible to keep the entire segregation degree in the ingot below 100% when the linear EMS's magnetic induction intensity is set to 0.036 T and the stirring frequency is 4 Hz. The ideal stirring parameters range for linear EMS is to maintain the magnetic induction intensity at around 0.036 T and the stirring frequency in the range of 4–8 Hz.
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- 2024
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3. On the Stochastic Dynamics of a Social Epidemics Model
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Xun-Yang Wang, Peng-Zhan Zhang, and Qing-Shan Yang
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Mathematics ,QA1-939 - Abstract
Alcohol abuse is a major social problem, which has caused a lot of damages or hidden dangers to the individual and the society. In this paper, with random factors of alcoholism considered in mortality rate of compartment populations, we formulate a stochastic alcoholism model according to compartment theory of infectious disease. Based on this model, we investigate the long-term stochastic dynamics behaviors of two equilibria of the corresponding deterministic model and point out the effect of random disturbance on the stability of the system. We find that when R0≤1, we get the estimation between the trajectory of stochastic system and E0=(Π/μs,0,0,0) in the average in time with respect to the disturbance intensity, while when R0>1, stochastic system is ergodic and has the unique stationary distribution. Finally, we carry out numerical simulations to support the corresponding theoretical results.
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- 2017
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4. Interfacial reaction between AZ91D magnesium alloy melt and mild steel under high temperature.
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Jia-hong Dai, Jian-yue Zhang, Bin Jiang, Xiang-jun Xu, Zhong-tao Jiang, Hong-mei Xie, Qing-shan Yang, and Guo-qing Zhang
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INTERFACIAL reactions ,MILD steel ,MELT spinning ,MAGNESIUM alloys ,HIGH temperatures ,MELTING - Abstract
The metallurgical quality control of magnesium (Mg) and Mg alloys in melting process is required to ensure a satisfied mechanical and corrosion performance, while the typical used steel crucible introduces impurities and interfacial interaction during melting process. Therefore, a systematic study about impurities diffusion and interfacial interaction between molten Mg and steel is necessary. In the present study, the interfacial reaction between molten AZ91D Mg alloy and mild steel during melting process was investigated with the melting temperatures of 700 °C, 750 °C and 800 °C. The results show that Al(Fe, Mn) intermetallic layer is the intermetallic primarily formed at the interfaces of AZ91D melt and mild steel. Meanwhile, Al
8 (Mn, Fe)5 is indexed between Al(Fe, Mn) and AZ91D. AlFe3 C appears between the mild steel and Al(Fe, Mn) at 700 °C and 750 °C, but absent at 800 °C due to the increased solubility of carbon in Mg matrix. It is found that the growth of the intermetallic layer is controlled by diffusion mechanism, and Al and Mn are the dominant diffusing species in the whole interfacial reaction process. By measuring the thickness of different layers, the growth constant was calculated. It increases from 1.89(±0.03)×10-12 m² ·s-1 at 700 °C to 3.05(±0.05)×10-12 m² ·s-1 at 750 °C, and 5.18(±0.05)×10-12 m² ·s-1 at 800 °C. Meanwhile, the content of Fe is linearly increased in AZ91D with the increase of holding time at 700 °C and 750 °C, while it shows a significantly increment after holding for 8 h at 800 °C, indicating holding temperature is more crucial to determine the Fe content of AZ91D than holding time. [ABSTRACT FROM AUTHOR]- Published
- 2024
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5. Study on Logging Identification Method of Complex Lithology in X Oilfield
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Ji-wei Ding, Hong-yu Ma, Qing-shan Yang, Yan Lu, and Shu-jun Yin
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- 2022
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6. LSPR-Based Cholesterol Biosensor Using Hollow Core Fiber Structure
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Qing Shan Yang, Brajesh Kumar Kaushik, Nan-Kuang Chen, Ragini Singh, Xia Zhang, and Santosh Kumar
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Materials science ,Optical fiber ,Cholesterol oxidase ,Scanning electron microscope ,010401 analytical chemistry ,Analytical chemistry ,Ascorbic acid ,01 natural sciences ,0104 chemical sciences ,law.invention ,law ,Colloidal gold ,Fiber ,Electrical and Electronic Engineering ,Surface plasmon resonance ,Instrumentation ,Biosensor - Abstract
In this paper, a cholesterol biosensor is developed using a single-mode fiber (SMF) and a hollow core fiber (HCF) to detect and measure the cholesterol concentration in the human body. The sensitivity of an SMF-HCF structure (sensor probe) has been enhanced by the localized surface plasmon resonance (LSPR) technique using the gold nanoparticles (AuNPs) of 11± 0.5 nm particle size. Furthermore, sensor probe was functionalized with cholesterol oxidase (ChOx) enzyme to increase the selectivity of biosensor. The synthesis of AuNPs is confirmed by a UV-visible spectrophotometer, transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDS). Furthermore, the coating of AuNPs over an optical fiber is verified by scanning electron microscope (SEM). The linearity range and detection limit of the proposed sensor are 50 nM– $1~\mu \text{M}$ and 25.5 nM, respectively. The selectivity of biosensor has been determined with the 10-mM concentration of different solutions of cholesterol, glucose, urea, ascorbic acid, L-cysteine, and galactose that are generally present in serum.
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- 2019
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7. Long noncoding RNA LINC00483/microRNA‐144 regulates radiosensitivity and epithelial–mesenchymal transition in lung adenocarcinoma by interacting with HOXA10
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Si‐Qi Yang, Qing‐Shan Yang, Bin Li, Peng Wang, Huai‐Hui Tang, Yuan‐Yuan Liu, and Ge Xu
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Male ,0301 basic medicine ,Epithelial-Mesenchymal Transition ,Lung Neoplasms ,Carcinogenesis ,Physiology ,Clinical Biochemistry ,Cell ,Down-Regulation ,Mice, Nude ,Adenocarcinoma of Lung ,Vimentin ,Binding, Competitive ,Models, Biological ,Radiation Tolerance ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,Cell Line, Tumor ,microRNA ,medicine ,Animals ,Humans ,Gene silencing ,Neoplasm Invasiveness ,Gene Silencing ,Epithelial–mesenchymal transition ,Cell Proliferation ,Base Sequence ,biology ,Cell growth ,Microarray analysis techniques ,Cell Biology ,Middle Aged ,Long non-coding RNA ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Homeobox A10 Proteins ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Female ,RNA, Long Noncoding - Abstract
Lung adenocarcinoma (LAD) is the leading cause of cancer death worldwide. Long noncoding RNAs (lncRNAs) have been shown to play an important regulatory role in cancer biology, including that of LAD. The aim of this experiment was to explore the interaction of LINC00483, microRNA-144 (miR-144), and homeobox A10 (HOXA10), and their effects on radio sensitivity and epithelial-mesenchymal transition (EMT) of LAD. Initially, microarray analysis was used to screen out miRNAs and lncRNAs, as well as the differentially expressed genes related to LAD. Following the screening process, the targeting relationship of LINC00483, miR-144, and that of miR-144 and HOXA10 was determined. Following that, the expression of LINC00483, miR-144, messenger RNA (mRNA), as well as protein expression of HOXA10, MMP-2, MMP-9, E-cadherin, vimentin, and N-cadherin that followed in cells was determined. Also, the effect of LINC00483 on cell migration and invasion ability, and cell tumorigenic ability was detected. LINC00483 and HOXA10 were found to be upregulated whereas miR-144 was downregulated in LAD. Silencing of LINC00483 could competitively bind to miR-144, thereby upregulating HOXA10. LINC00483 or HOXA10 silencing led to decreased HOXA10, MMP-2, MMP-9, vimentin, and N-cadherin but elevated miR-144 and E-cadherin. Moreover, after being transfected with silenced LINC00483, the cell proliferation, migration, and invasion were inhibited with enhanced radiosensitivity. Consequently, the data of the study indicates that interference of LINC00483 weakens its competitive binding ability to miR-144, thus reducing HOXA10 expression, and enhancing radiosensitivity in LAD.
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- 2019
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8. An integrated approach for remanufacturing job shop scheduling with routing alternatives
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Lingling Li, Congbo Li, Li Li, Ying Tang, and Qing Shan Yang
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business.product_category ,Workstation ,Computer science ,Job shop ,Decision Making ,Scheduling (production processes) ,02 engineering and technology ,Workflow ,law.invention ,law ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,Industry ,Computer Simulation ,Recycling ,Remanufacturing ,Models, Statistical ,Job shop scheduling ,Applied Mathematics ,05 social sciences ,Equipment Design ,General Medicine ,Petri net ,Industrial engineering ,Machine tool ,Computational Mathematics ,Models, Organizational ,Modeling and Simulation ,Simulated annealing ,020201 artificial intelligence & image processing ,General Agricultural and Biological Sciences ,business ,Algorithms ,Software ,050203 business & management - Abstract
Remanufacturing is a practice of growing importance due to increasing environmental awareness and regulations. However, the stochastic natures inherent in the remanufacturing processes complicate its scheduling. This paper undertakes the challenge and presents a remanufacturing job shop scheduling approach by integrating alternative routing assignment and machine resource dispatching. A colored timed Petri net is introduced to model the dynamics of remanufacturing process, such as various process routings, uncertain operation times for cores, and machine resource conflicts. With the color attributes in Petri nets, two types of decision points, recovery routing selection and resource dispatching, are introduced and linked with places in CTPN model. With time attributes in Petri nets, the temporal aspect of recovery operations for cores as well as the evolution dynamics in cores' operational stages is mathematically analyzed. A hybrid meta-heuristic algorithm embedded scheduling strategy over CTPN is proposed to search for the optimal recovery routings for worn cores and their recovery operation sequences on workstations, in minimizing the total production cost. The approach is demonstrated through the remanufacturing of used machine tool and its effectiveness is compared against another two cases: baseline case with fixed recovery process routings and case 2 using standard SA/MST.
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- 2019
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9. Retracted : Downregulated expression of microRNA‐329 inhibits apoptosis of nigral dopaminergic neurons by regulating CDKN2D expression via the FoxO3a signaling pathway in rats with Parkinson's disease
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Yi-Nan Zhang, Yuan-Yuan Liu, and Qing-Shan Yang
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0301 basic medicine ,Parkinson's disease ,Physiology ,Clinical Biochemistry ,Apoptosis ,Substantia nigra ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Animals ,Humans ,Cyclin-Dependent Kinase Inhibitor p19 ,RNA, Small Interfering ,Protein kinase B ,TUNEL assay ,Tyrosine hydroxylase ,Caspase 3 ,Chemistry ,Dopaminergic Neurons ,Forkhead Box Protein O3 ,Dopaminergic ,Parkinson Disease ,Cell Biology ,medicine.disease ,Rats ,Cell biology ,Substantia Nigra ,MicroRNAs ,030104 developmental biology ,Gene Expression Regulation ,Proto-Oncogene Proteins c-bcl-2 ,nervous system ,Signal transduction ,030217 neurology & neurosurgery ,Signal Transduction - Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder due to the loss of dopaminergic neurons in the substantia nigra. This study focuses on the effect of microRNA-329 (miR-329) on nigral dopaminergic neurons in a rat model of PD via the FoxO3a signaling pathway by binding to CDKN2D. Brain tissues from the substantia nigra were taken from the rats in two groups. TUNEL staining was used to observe tyrosine hydroxylase (TH)-positive neurons. Nigral dopaminergic neurons were randomized into the normal, blank, negative control (NC), miR-329 mimics, miR-329 inhibitors, small interfering (siRNA)-CDKN2D, and miR-329 inhibitors + siRNA-CDKN2D groups. Expressions of miR-329, CDKN2D, FoxO3a, AKT, caspase-3 and Bcl-2 were determined using RT-qPCR and western blotting. Apoptosis rate of nigral dopaminergic neurons in 7 groups was determined by flow cytometry. Compared with the blank and NC groups, the miR-329 mimics group showed increased miR-329 and caspase-3 expressions as well as decreased expressions of CDKN2D, FoxO3a, AKT, and Bcl-2, the siRNA-CDKN2D group indicated enhanced expressions of caspase-3 and declined expressions of CDKN2D, FoxO3a, AKT, and Bcl-2, and the miR-329 inhibitors group revealed decreased miR-329 and caspase-3 expressions and increased expressions of CDKN2D, FoxO3a, AKT, and Bcl-2. The apoptosis rate of nigral dopaminergic neurons was significantly increased in the miR-329 mimics and siRNA-CDKN2D groups, but was decreased in the miR-329 inhibitors group. Our data suggested that downregulated miR-329 could inhibit apoptosis of nigral dopaminergic neurons in a rat model of PD by upregulating the expression of CDKN2D via the activation of the FoxO3a signaling pathway.
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- 2018
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10. Up-Regulation of MicroRNA-133a Inhibits the MEK/ERK Signaling Pathway to Promote Cell Apoptosis and Enhance Radio-Sensitivity by Targeting EGFR in Esophageal Cancer In Vivo and In Vitro
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Qing-Shan Yang, Li-Peng Jiang, Chun-Yan He, Yuan-Yuan Liu, and Yu-Na Tong
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0301 basic medicine ,MAPK/ERK pathway ,medicine.diagnostic_test ,Cell ,Cell Biology ,Transfection ,Biology ,Biochemistry ,Molecular biology ,Flow cytometry ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Apoptosis ,Cell culture ,030220 oncology & carcinogenesis ,microRNA ,medicine ,Signal transduction ,Molecular Biology - Abstract
This study aims to explore how microRNA-133a (miR-133a) affects cell apoptosis and radio-sensitivity by targeting EGFR via regulating MEK/ERK pathway in esophageal cancer (EC). A total of 358 EC patients were selected and assigned into the resistant and sensitive groups. Human EC KYSE 150 cell line was assigned into the blank, negative control (NC), miR-133a mimic, miR-133a inhibitors, si-EGFR, miR-133a inhibitors + si-EGFR groups after transfection. MiR-133a and EGFR mRNA expressions were detected by qRT-PCR and EGFR, MEK/ERK pathway-related protein expressions were detected by Western blotting. The radio-sensitivity and cell apoptosis were testified by clone formation and flow cytometry. MiR-133a was up-regulated but EGFR was down-regulated in the sensitive group than in the resistant group. Compared with the blank and NC groups, the miR-133a mimic and si-EGFR groups exhibited increased cell apoptosis rate but decreased EGFR, p-MEK1/2, and p-ERK1/2 protein expressions; while opposite trend was observed in the miR-133a inhibitors group. Compared with the miR-133a inhibitors group, the miR-133a inhibitors + si-EGFR group presented reduced cell survival rate, EGFR, p-MEK1/2, and p-ERK1/2 protein expressions but increased cell apoptosis rate. These results indicated that miR-133a could inhibit the MEK/ERK pathway to promote cell apoptosis and enhance radio-sensitivity by targeting EGFR in EC. J. Cell. Biochem. 118: 2625-2634, 2017. © 2017 Wiley Periodicals, Inc.
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- 2017
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11. Microstructure Evolution and Mechanical Properties of Extruded Mg-Al-Zn-Sn Alloy Sheets
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Wen Jun Liu, Qing Shan Yang, and Zu Jian Yu
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010302 applied physics ,Materials science ,Scanning electron microscope ,Mechanical Engineering ,Alloy ,Metallurgy ,02 engineering and technology ,Slip (materials science) ,engineering.material ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,01 natural sciences ,law.invention ,Optical microscope ,Mechanics of Materials ,Dimple ,law ,0103 physical sciences ,engineering ,General Materials Science ,Extrusion ,0210 nano-technology ,Ductility - Abstract
The microstructure and mechanical responses of the AZ31 with the addition of 1.8% Sn alloys have been studied and compared. Mg alloy sheets were prepared with metal model casting method and subsequent processes by conventional extrusion (CE) and differential speed extrusion (DSE). Mg alloys were hot extruded at 400oC with the extrusion ratio of 101:1. The microstructure of Mg alloy sheets was examined by optical microscopy (OM) and scanning electron microscope (SEM). The results indicated that the grains were dynamically recrystallized after the extrusion process. Moreover, DSE process dramatically enhanced the room temperature ductility of the extruded sheets. It was also presented that the Mg alloy processed by DSE exhibite a classical dimple structure as a result of slip accumulation and ductile tear.
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- 2017
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12. Sensor selection approach for damage identification based on response sensitivity
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Qing-Shan Yang and Juan Wang
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Identification (information) ,Response sensitivity ,business.industry ,Computer science ,Sensor selection ,Pattern recognition ,Artificial intelligence ,Safety, Risk, Reliability and Quality ,business ,Civil and Structural Engineering - Published
- 2017
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13. Plebeins A-F, sesquiterpenoids and diterpenoids from Salvia plebeian
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Min-Rong Jin, Gui-Xin Chou, Qing-Shan Yang, and Cheng-Gang Zhang
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biology ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Absolute configuration ,04 agricultural and veterinary sciences ,Plant Science ,Salvia ,biology.organism_classification ,040401 food science ,01 natural sciences ,Biochemistry ,Terpenoid ,0104 chemical sciences ,0404 agricultural biotechnology ,Salvia plebeia ,Agronomy and Crop Science ,Biotechnology - Abstract
Plebein A ( 1 ), a sesquiterpenoid with a novel skeleton and another sesquiterpenoid, plebein B ( 2 ), and four new diterpenoids plebeins C-F ( 4–7 ), along with six known compounds were isolated from the whole plant of Salvia plebeia R. Br. The absolute configuration of 2 was established by an X-ray crystallographic study. In addition, compounds 4 , 6 and 9 showed anti-proliferative activity against CaCo2 and MCF-7 cell lines, with IC 50 values ranging from 9.65 μM to 45.96 μM.
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- 2017
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14. Transcriptome analysis of Clinopodium gracile (Benth.) Matsum and identification of genes related to Triterpenoid Saponin biosynthesis
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Chenkai Wang, Qing-Shan Yang, Kelong Ma, Chunmiao Shan, Shengxiang Zhang, Jiawen Wu, and Yuanyuan Shi
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Candidate gene ,lcsh:QH426-470 ,lcsh:Biotechnology ,Secondary Metabolism ,RNA-Seq ,Biology ,Real-Time Polymerase Chain Reaction ,Proteomics ,Clinopodium gracile (Benth.) Matsum ,Transcriptome ,Magnoliopsida ,lcsh:TP248.13-248.65 ,Gene expression ,Genetics ,Triterpenoid saponin biosynthesis ,Gene ,Triterpenoid saponin ,chemistry.chemical_classification ,Saponins ,Triterpenes ,Biosynthetic Pathways ,lcsh:Genetics ,Farnesyl-Diphosphate Farnesyltransferase ,chemistry ,Biochemistry ,Differentially expressed genes ,DNA microarray ,Research Article ,Transcription Factors ,Biotechnology - Abstract
Background Clinopodium gracile (Benth.) Matsum (C. gracile) is an annual herb with pharmacological properties effective in the treatment of various diseases, including hepatic carcinoma. Triterpenoid saponins are crucial bioactive compounds in C. gracile. However, the molecular understanding of the triterpenoid saponin biosynthesis pathway remains unclear. Results In this study, we performed RNA sequencing (RNA-Seq) analysis of the flowers, leaves, roots, and stems of C. gracile plants using the BGISEQ-500 platform. The assembly of transcripts from all four types of tissues generated 128,856 unigenes, of which 99,020 were mapped to several public databases for functional annotation. Differentially expressed genes (DEGs) were identified via the comparison of gene expression levels between leaves and other tissues (flowers, roots, and stems). Multiple genes encoding pivotal enzymes, such as squalene synthase (SS), or transcription factors (TFs) related to triterpenoid saponin biosynthesis were identified and further analyzed. The expression levels of unigenes encoding important enzymes were verified by quantitative real-time PCR (qRT-PCR). Different chemical constituents of triterpenoid saponins were identified by Ultra-Performance Liquid Chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS). Conclusions Our results greatly extend the public transcriptome dataset of C. gracile and provide valuable information for the identification of candidate genes involved in the biosynthesis of triterpenoid saponins and other important secondary metabolites.
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- 2020
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15. [Cloning and characterization of chalcone synthase and chalcone isomerase genes in Arisaema heterophyllum]
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Sheng-Xiang, Zhang, Yuan-Yuan, Shi, Chen-Kai, Wang, De-Rui, Zhao, Qing-Shan, Yang, Ke-Long, Ma, and Jia-Wen, Wu
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Cloning, Molecular ,Intramolecular Lyases ,Acyltransferases ,Arisaema ,Plant Proteins - Abstract
Chalcone synthase( CHS) and chalcone isomerase( CHI) are key enzymes in the biosynthesis pathway of flavonoids. In this study,unigenes for CHS and CHI were screened from the transcriptome database of Arisaema heterophyllum. The open reading frame( ORFs) of chalcone synthase( Ah CHS) and chalcone isomerase( Ah CHI) were cloned from the plant by RT-PCR. The physicochemical properties,expression and structure characteristics of the encoded proteins Ah CHS and Ah CHI were analyzed. The ORFs of Ah CHS and Ah CHI were 1 176,630 bp in length and encoded 392,209 amino acids,respectively. Ah CHS functioned as a symmetric homodimer. The N-terminal helix of one monomer entwined with the corresponding helix of another monomer. Each CHS monomer consisted of two structural domains. In particular,four conserved residues define the active site. The tertiary structure of Ah CHI revealed a novel open-faced β-sandwich fold. A large β-sheet( β4-β11) and a layer of α-helices( α1-α7) comprised the core structure. The residues spanning β4,β5,α4,and α6 in the three-dimensional structure were conserved among CHIs from different species. Notably,these structural elements formed the active site on the protein surface,and the topology of the active-site cleft defined the stereochemistry of the cyclization reaction. The homology comparison showed that Ah CHS had the highest similarity to the CHS of Anthurium andraeanum,while Ah CHI had the highest similarity to the CHI of Paeonia delavayi. This study provided the basis for the functional study of Ah CHS and Ah CHI and the further study on plant flavonoid biosynthesis pathway.
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- 2019
16. LSPR-based cholesterol biosensor using a tapered optical fiber structure
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Wenjun Wang, Nan-Kuang Chen, Qing Shan Yang, Santosh Kumar, Xia Zhang, Brajesh Kumar Kaushik, Ragini Singh, and Bingyuan Zhang
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Detection limit ,0303 health sciences ,Optical fiber ,Materials science ,Cholesterol oxidase ,business.industry ,Scanning electron microscope ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Article ,law.invention ,010309 optics ,03 medical and health sciences ,Fiber optic sensor ,Colloidal gold ,law ,0103 physical sciences ,Optoelectronics ,Surface plasmon resonance ,business ,Biosensor ,030304 developmental biology ,Biotechnology - Abstract
Accurate cholesterol level measurement plays an important role in the diagnosis of severe diseases such as cardiovascular diseases, hypertension, anemia, myxedemia, hyperthyroidism, coronary artery illness. Traditionally, electrochemical sensors have been employed to detect the cholesterol level. However, these sensors have limitations in terms of sensitivity and selectivity. In this paper, a localized surface plasmon resonance (LSPR) -based biosensor is demonstrated that accurately detects and measures the concentration of cholesterol. In the present study, a tapered optical fiber-based sensor probe is developed using gold nanoparticles (AuNPs) and cholesterol oxidase (ChOx) to increase the sensitivity and selectivity of the sensor. Synthesized AuNPs were characterized by UV-visible spectrophotometer, transmission electron microscope (TEM), and energy dispersive X-ray spectroscopy (EDS). Further, coating of AuNPs over fiber was confirmed by scanning electron microscope (SEM). The developed sensor demonstrates for a clinically important cholesterol range of 0 to 10 mM, and the limit of detection is found to be 53.1 nM.
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- 2019
17. Comparative Study of Damage and Hysteretic Energy Characteristics of an RC Continuous Girder Bridge under Strong Near-Fault and Far-Field Earthquakes
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Hui Jiang, Xiao-yu Bai, Qing-shan Yang, Shuo Yang, and Ya-guang Zeng
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Pier ,Engineering ,Nonlinear system ,Peak ground acceleration ,business.industry ,Magnitude (mathematics) ,Geotechnical engineering ,Structural engineering ,Induced seismicity ,business ,Bridge (interpersonal) ,Finite element method ,Characteristic energy - Abstract
A finite element model of a bridge that considers the nonlinear mechanical behavior of piers was built using a reinforced concrete continuous girder bridge in an expressway as the subject. Comparative analysis via nonlinear time history integration was conducted to determine the influences of frequency characteristics, peak ground acceleration (PGA), and effective duration on the magnitude and distribution of hysteretic energy and structural damage under selected typical near-fault and far-field earthquake records. The following conclusions were drawn from the result: (1) the frequency characteristics of ground motion significantly influenced the seismic response of the bridge structure, and an increase in PGA would obviously increase hysteretic energy and damage; (2) the hysteretic energy and damage of the bridge piers under near-fault earthquakes were greater than those under far-field earthquakes at the same PGA and duration, and the position of damage was considerably higher; (3) the proportio...
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- 2016
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18. circRNA_0006393 promotes osteogenesis in glucocorticoid‑induced osteoporosis by sponging miR‑145‑5p and upregulating FOXO1
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Zhi‑Xin Chen, Peng‑Biao Li, Qing‑Shan Yang, Dachuan Wang, Song‑Bo Shi, Shi‑Fang Guo, and Xing‑Bo Wang
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0301 basic medicine ,Adult ,Male ,Cancer Research ,Cell ,Down-Regulation ,FOXO1 ,Biochemistry ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Osteogenesis ,microRNA ,Genetics ,medicine ,Animals ,Humans ,Molecular Biology ,Glucocorticoids ,Cells, Cultured ,Aged ,Oncogene ,Chemistry ,Forkhead Box Protein O1 ,Transfection ,RNA, Circular ,Cell cycle ,Middle Aged ,Molecular medicine ,Up-Regulation ,Mice, Inbred C57BL ,MicroRNAs ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Cancer research ,Molecular Medicine ,Osteoporosis ,Female - Abstract
Glucocorticoids are the most common cause of glucocorticoid‑induced osteoporosis (GIOP). Moreover, the role of circular RNAs (circRNAs) in the regulation of bone metabolism remains unclear. Therefore, in the present study, it was hypothesized that hsa_circ_0006393 may play an important role in GIOP. To investigate the role of circRNAs in GIOP, treatment with dexamethasone or transfection with a vector overexpressing hsa_circ_0006393 were performed using in vitro cell and in vivo mouse models. Reverse transcription‑quantitative PCR, fluorescence in situ hybridization and western blotting were performed to investigate the function of hsa_circ_0006393 in vitro. In addition, the effects of hsa_circ_0006393 on osteogenesis were investigated. Dual‑energy X‑ray absorptiometry analysis was performed to examine the osteogenic potential of hsa_circ_0006393 in vivo. Moreover, the mechanism underlying hsa_circ_0006393‑mediated bone metabolism regulation via the microRNA (miR)‑145‑5p/forkhead box O1 (FOXO1) pathway was investigated. The present results suggested that the expression level of hsa_circ_0006393 was decreased in patients with GIOP. Furthermore, the overexpression of hsa_circ_0006393 increased the expression level of genes associated with osteogenesis. Moreover, hsa_circ_0006393 was identified to be localized mainly in the cytoplasm and nucleus of bone marrow mesenchymal stem cells. miR‑145‑5p was found to be directly targeted by hsa_circ_0006393. Collectively, hsa_circ_0006393 increases the expression levels of osteogenic genes during bone remodeling by sponging miR‑145‑5p and upregulating FOXO1.
- Published
- 2018
19. [Cloning and expression analysis of 1-deoxy-D-xylulose-5-phosphate reductoisomerase gene (CcDXR1) in Cinnamomum camphora L.) Presl]
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Han, Zheng, Li, Jing, Na, Yao, Qing-shan, Yang, Hua-sheng, Peng, Ye, Shen, and Lu-qi, Huang
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DNA, Complementary ,Erythritol ,Cinnamomum camphora ,Terpenes ,Sugar Phosphates ,Amino Acid Sequence ,Cloning, Molecular ,Genes, Plant ,Sequence Alignment ,Aldose-Ketose Isomerases ,Phylogeny ,Plant Proteins - Abstract
1-Deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) is the second rate-limiting enzyme of terpenoid biosynthesis in the methylerythritol-4-phosphate pathway. According to the transcriptome database of Cinnamomum camphora, the DXR cDNA was cloned by rapid amplification of cDNA ends (RACE) from C. camphora, and was named CcDXR1(GenBank number: KU886266). The ORF of CcDXR1 is composed of 1 413 bp, and it encodes 470 amino acids. The bioinformatics analysis suggests that the molecular weight of the encoded protein is 51.1 kD and the theoretically isoelectric point is 6.62, and there is no signal peptide and transmembrane structure in putative protein. The analysis of sequence alignment and phylogenetic tree showed that the CcDXR1 belonged to the DXR family. The results of the realtime PCR indicated that expression level of CcDXR1 in mature leaves was higher than tender leaves, which in roots was similar to leaves and the lowest in branches. The camphor is divided into five chemotypes, according to the main chemical compounds in C. camphora. It also showed that the expression level of CcDXR1 in borneol C. camphora was highest than that in cineol, iso-nerolidol, camphor and linalool. Our results revealed that the expression level of CcDXR1 exhibits diversity among plant tissues, growth periods and five chemical types, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.
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- 2018
20. Abietane diterpenoids from Caryopteris incana (Thunb.) Miq
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Sen-Miao Zhao, Qing-Shan Yang, Gui-Xin Chou, Jian-Li Zhou, and Wei Wang
- Subjects
Magnetic Resonance Spectroscopy ,Spectrophotometry, Infrared ,Stereochemistry ,Crystallography, X-Ray ,01 natural sciences ,Biochemistry ,Mass Spectrometry ,Dipeptidyl peptidase ,chemistry.chemical_compound ,Physical and Theoretical Chemistry ,Abietane ,Caryopteris incana ,Lamiaceae ,biology ,010405 organic chemistry ,Organic Chemistry ,Nuclear magnetic resonance spectroscopy ,biology.organism_classification ,In vitro ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry ,Abietanes ,Two-dimensional nuclear magnetic resonance spectroscopy ,Human cancer - Abstract
Twelve new diterpenes, caryopincaolide A-L (1-4, 11-12, 16-19, 27-28), together with twenty-eight known diterpenes, have been isolated from the whole plant of Caryopteris incana (Thunb.) Miq. Their structures were elucidated on the basis of 1D and 2D NMR, IR, X-ray crystal diffraction and mass spectroscopic data, as well as ECD calculations. All compounds were tested for in vitro dipeptidyl peptidase IV (DPP-IV) inhibitory activity, with compounds 3, 4, 28, 29, and 40 exhibiting DPP-IV inhibitory effects with IC50 values ranging from 54.2 to 228.9 μM. Compounds 1, 3 and 4 also showed potent activity toward the inhibition of the growth of human cancer cells and 1 can induce apoptosis in Hey and A-549 cells.
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- 2016
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21. Effect of Extrusion Strain Path on Microstructure and Properties of AZ31 Magnesium Alloy Sheet
- Author
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Dai Qingwei, Bin Jiang, Su-Qin Luo, Yu Zujian, and Qing-Shan Yang
- Subjects
Materials science ,Metallurgy ,Alloy ,Metals and Alloys ,engineering.material ,Microstructure ,Industrial and Manufacturing Engineering ,Shear (sheet metal) ,engineering ,Shear stress ,Formability ,Extrusion ,Texture (crystalline) ,Magnesium alloy - Abstract
The mechanical properties of AZ31 magnesium alloy sheets processed by different extrusion strain paths were examined in correlation with concurrent microstructure and texture evolution. The conventional extrusion (CE) and asymmetric extrusion (ASE) paths were performed on Mg alloy sheets. The textures at near surface and mid-layer of ASE sheets were various throughout sheet thickness direction as a result of extra asymmetric shear strain. This can stimulate the orientation of (0002) basal planes to incline approximately 12° toward the shear direction. Moreover, the basal texture of ASE sheet was weakened compared with CE one. Enhancing the ambient formability of extruded Mg alloy sheet fabricated by ASE path was accomplished by the tilted weak basal texture.
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- 2015
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22. Microstructural Evolution and Mechanical Behavior of AZ31 Magnesium Alloy Sheets with Li Addition
- Author
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Bo Song, Bin Jiang, Qing Shan Yang, Fu Sheng Pan, Su Qing Luo, and Wei Jiang
- Subjects
Materials science ,Mechanical Engineering ,Alloy ,Metallurgy ,chemistry.chemical_element ,engineering.material ,Condensed Matter Physics ,Microstructure ,chemistry ,Mechanics of Materials ,engineering ,General Materials Science ,Extrusion ,Lithium ,Texture (crystalline) ,Magnesium alloy ,Ductility ,Electron backscatter diffraction - Abstract
AZ31 magnesium alloy and its alloy with 5% lithium were extruded to 1mm in thickness sheets at 380 oC with extrusion ratio of 101. Microstructure evolution and mechanical behavior of the extruded Mg alloy sheets were examined. The microstructure and texture evolution were investigate by electronic backscattered diffraction (EBSD) and X-ray diffraction (XRD). Mechanical performance was carried out by tensile tests at room temperature. In addition, the evolution of neutral layer and microstructure was also examined by V-bending. It was found that Li addition resulted in the strong divergence of the grain orientation. (0002) basal texture of AZ31 alloy sheets with 5% lithium has been weakened. The room temperature ductility of these textural sheets was enhanced owing to the tilted weak basal texture. Moreover, it exhibits superior ductility during V-bending process at room temperature.
- Published
- 2015
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23. Microstructure and Mechanical Responses of Extruded Magnesium Alloy Sheets with Lithium Addition
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Zheng Yuan Gao, Qing Shan Yang, Bin Jiang, Jun Jie He, Fu Sheng Pan, and Jia Hong Dai
- Subjects
Materials science ,Mechanical Engineering ,Alloy ,Metallurgy ,chemistry.chemical_element ,engineering.material ,Condensed Matter Physics ,Microstructure ,chemistry ,Mechanics of Materials ,Ultimate tensile strength ,engineering ,General Materials Science ,Lithium ,Texture (crystalline) ,Magnesium alloy ,Ductility ,Electron backscatter diffraction - Abstract
After 5% lithium was added to AZ31 magnesium alloy, the alloy was extruded at 380oC with the extrusion ratio of 101. Mechanical responses and microstructure evolution were investigated. The microstructure and texture evolution were examined by electronic backscattered diffraction (EBSD) and X-ray diffraction (XRD). Tensile tests in the tensile directions of 0o, 45oand 90owere carried out at room temperature. Lithium addition brought about the strong divergence of the grain orientation and triggered the spread of the (0002) basal texture. The room temperature ductility of the extruded Mg alloy sheets was improved due to the tilted weak basal texture.
- Published
- 2015
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24. Comparation about Refining Efficiency to Microstructure of AZ31 Magnesium Alloy for Sr Master Alloys
- Author
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Su Qin Luo, Bo Liu, Qing Shan Yang, Fu Sheng Pan, Bin Jiang, Wenjun Liu, and Ren Ju Cheng
- Subjects
Materials science ,chemistry ,Mechanics of Materials ,Magnesium ,Mechanical Engineering ,Metallurgy ,chemistry.chemical_element ,General Materials Science ,Magnesium alloy ,Condensed Matter Physics ,Microstructure ,Refining (metallurgy) - Abstract
In the present work, the influence of Al-Sr and Mg-Sr master alloys on the as-cast microstructure of the AZ31 magnesium alloy was investigated,and the refinement efficiencies of both master alloys were also analyzed and compared. The research results indicate that both the Al-Sr and Mg-Sr master alloys have obvious refinement effect on the as-cast microstructure of the AZ31 magnesium alloy, and the refinement efficiency of the Mg-Sr master alloys was better than that of the Al-Sr master alloys. The mechanisms for the differences of grain refinement efficiency between Al-Sr and Mg-Sr master alloys on the AZ31 magnesium alloys were also discussed.
- Published
- 2015
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25. A Theory Treatment of Pedestrian-Induced Lateral Vibration of Structure
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Qing shan Yang and Yan-an Gao
- Subjects
Materials science ,Mechanical Engineering ,Acoustics ,Stiffness ,020101 civil engineering ,02 engineering and technology ,0201 civil engineering ,Computer Science Applications ,Vibration ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Control and Systems Engineering ,medicine ,medicine.symptom ,Instrumentation ,Excitation ,Information Systems - Abstract
The lateral excessive sway motion caused by pedestrian traffic has attracted great public attention in the past decades years. However, the theories about exploring the effect of pedestrian on the lateral dynamic properties of structure are scarce. The new contribution of this paper is that a new pedestrian-structure system is proposed for exploring the effect of human on structural dynamic properties based on a sway assumption. Study shows that pedestrian deteriorates the natural frequency of structure and improves structural damping. The influence tendencies of pedestrian on structure can be supported by measurements. The further parametric study shows that the changes of human dynamic parameters have some evident impacts on structural dynamic performances. For example, the increase of leg damping can trigger an improvement of structural damping capacity. In addition, the walking step frequency closing structural harmonic natural frequency can incur the worst response. The increase of step width deteriorates lateral vibration and structural frequency but can slightly improve structural damping. One of essential reasons influencing structural lateral dynamic properties is the dynamic human system including body mass, damping, stiffness, and its motion behavior such as step frequency. This theory is proposed to analyze how pedestrian alters the lateral dynamic performances on those sensitive structures such as the footbridges or stadium bleachers. For example, how the variation of step width influences the change of natural frequency of structure?
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- 2017
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26. Nepetaefolins A-J, Cytotoxic Chinane and Abietane Diterpenoids from Caryopteris nepetaefolia
- Author
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Xu-Dong Mao, Qing-Shan Yang, Cheng-Gang Zhang, Jian-Li Zhou, and Gui-Xin Chou
- Subjects
Stereochemistry ,Molecular Conformation ,Pharmaceutical Science ,Caryopteris ,Crystallography, X-Ray ,01 natural sciences ,Molecular conformation ,Analytical Chemistry ,chemistry.chemical_compound ,Drug Discovery ,Verbenaceae ,Ic50 values ,Cytotoxic T cell ,Humans ,Cytotoxicity ,Nuclear Magnetic Resonance, Biomolecular ,Abietane ,Pharmacology ,biology ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Paclitaxel ,chemistry ,Abietanes ,Molecular Medicine ,Diterpenes ,Drug Screening Assays, Antitumor ,Chemosensitivity assay ,Drugs, Chinese Herbal - Abstract
Nepetaefolins A–J (1–10) and seven known compounds were isolated from the whole plant of Caryopteris nepetaefolia. The absolute configurations of 1–3 were determined from single-crystal X-ray diffraction and spectroscopic data. Compounds 6 and 7, with IC50 values of 6.3–9.0 μM, showed higher cytotoxicity than paclitaxel in one non-small-cell lung cancer, patient-derived xenograft (PDX) model when tested using PDX models and the adenosine triphosphate-tumor chemosensitivity assay (ATP-TCA).
- Published
- 2017
27. Wrinkled membrane element based on the wrinkling potential
- Author
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Qing Shan Yang, Siu-Seong Law, and Xiaofeng Wang
- Subjects
Materials science ,Computation ,Flow (psychology) ,Shell (structure) ,Materials Science(all) ,Modelling and Simulation ,Stability theory ,Shell ,General Materials Science ,Tensor ,Modified constitutive relationship ,business.industry ,Applied Mathematics ,Mechanical Engineering ,Membrane ,Wrinkling strain ,Infinitesimal strain theory ,Structural engineering ,Mechanics ,Condensed Matter Physics ,Wrinkling potential ,Objectivity (frame invariance) ,Mechanics of Materials ,Modeling and Simulation ,business ,Normal - Abstract
For a membrane structure, wrinkles have an important effect on its mechanical behaviors. Wrinkling level characterizes the development of wrinkles and reflects the performance of a membrane in its service, and it plays a very significant role in the wrinkling analysis. The shell elements combined with the stability theory would be an ideal solution to the wrinkling problem. However, this approach requires a dense mesh and the computation is very time consuming. Also the wrinkling parameters are very sensitive to the size of shell elements. Existing wrinkling models based on membrane elements are derived from the Tension Field Theory which are incapable of describing fully the wrinkling behaviors. A new wrinkling model adopting the wrinkling strain as a measure of the wrinkling level is proposed in this paper to address these issues. According to the analogy between the wrinkling strain and the elasto-plastic strain, a wrinkling potential surface is assumed to exist and its normal direction defines the direction of the wrinkling strain tensor by virtue of the flow rule. Based on the consistent condition of the wrinkling potential surface, a modified constitutive tensor is obtained. To avoid the switching of the wrinkling state in the numerical solution, a new wrinkling criterion is proposed, in which the predominant influence of the previous state is included. Besides, a new approach to determine the wrinkling orientation is given to improve the efficiency of convergence in the slack region. The objectivity of the wrinkling coordinate frame is also demonstrated as an accompanying set of results. Finally, two benchmark problems are analyzed with the proposed wrinkling model, and their results are compared with those in the literatures. Results indicate that the proposed wrinkling model is valid and accurate to characterize the wrinkling level of a membrane and it exhibits efficient convergence even in the slack region.
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- 2014
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28. Assembly of an unprecedented metal-pipemidic acid complex modifying octamolybdates containing like DNA spiral chain
- Author
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Jingquan Sha, Yu Zhang, Xiao-Ning Yang, Liang Li, Qing-Shan Yang, Hong Yan, Qian-Nan Zhang, and Dong-Wen Wang
- Subjects
Antitumor activity ,Chemistry ,Stereochemistry ,Pipemidic acid ,General Chemistry ,Condensed Matter Physics ,Metal ,chemistry.chemical_compound ,Chain (algebraic topology) ,visual_art ,visual_art.visual_art_medium ,medicine ,General Materials Science ,Selectivity ,DNA ,medicine.drug - Abstract
By introducing antibacterial drugs pipemidic acid into the octamolybdates, an unprecedented compound, [Zn(PPA)2(H2O)]2·[Mo8O26]·3.5H2O (1) (PPA = pipemidic acid), has been synthesized and characterized by routine physical methods. Single-crystal X-ray diffraction analysis reveals that the title compound contains the right- and left-double-stranded like DNA helical chains, which are assembled together via sharing the β-Mo8 clusters forming the fascinating double intertwined inverted helices. The result of the antitumor activities shows that the title compound possesses higher antitumor activity and selectivity.
- Published
- 2014
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29. Form Finding and Loading Analysis of ETFE Cushions Using Interaction Numerical Model
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Peng Li and Qing Shan Yang
- Subjects
chemistry.chemical_compound ,Engineering ,ETFE ,chemistry ,business.industry ,Cushion ,General Medicine ,Structural engineering ,Fe model ,business - Abstract
The enclosed air plays a significant role in form-finding and loading analysis of ETFE cushions. A new numerical model of ETFE cushions is proposed in order to consider the interaction effects between outer membrane and internal air. Then the form-finding and loading analysis of a regular hexagon ETFE cushion are performed and compared with experimental study. It is shown that the numerical results are in good agreement with the test results. The interaction FE model can be used in static analysis of ETFE cushions.
- Published
- 2013
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30. Influence of microstructural evolution on mechanical behaviour of AZ31 alloy sheet processed by flat extrusion container
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X Y Huang, Guanyu Zhou, Qing Shan Yang, Fu Sheng Pan, Jiahong Dai, and Bin Jiang
- Subjects
Microstructural evolution ,Materials science ,Mechanics of Materials ,Annealing (metallurgy) ,Mechanical Engineering ,Metallurgy ,General Materials Science ,Extrusion ,Condensed Matter Physics ,Anisotropy ,AZ31 alloy - Abstract
Influence of microstructural evolution on the mechanical behaviour of AZ31 alloy sheet processed by flat extrusion container is analysed upon annealing treatments. The basal texture is significantly increased as a result of the formation of new grains with a largely altered c axis orientation relative to the initial basal orientation owing to static recrystallisation. The results reveal that the ductility of the alloys without annealing treatments is the highest, but the strength is the lowest, which confirms the strong anisotropy of stress–strain behaviour with respect to the initial textures. Significant differences in the stress–strain curves are observed for the as received and annealed specimens.
- Published
- 2013
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31. Research on Seismic Response Estimation of Reinforced Concrete Pier under Pulse-Type Near-Fault Ground Motion
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Xiu Li Du, Qing Shan Yang, and Yan Li Shen
- Subjects
Ground motion ,Pier ,Engineering ,Nonlinear system ,business.industry ,General Medicine ,Structural engineering ,Type (model theory) ,business ,Response spectrum ,Incremental Dynamic Analysis ,Displacement (vector) ,Pulse (physics) - Abstract
For estimating seismic response of pier-structure under near-fault ground motion, The typical pulse-type near-fault ground motion records were chosen to establish a record base, and three pier models with different natural period were established; The non-elastic response spectral displacement of ground motion was used to estimate the nonlinear response; The yield displacement of the nonlinear oscillator was defined based on the static pushover analysis result, and its influence on response estimation was studied. The study result is important for structural seismic response estimation by using the non-elastic response spectral displacement and the probability-based seismic performance evaluation.
- Published
- 2013
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32. Effects of Geometrical Factors on Wind Pressure Characteristics of Cylindrical Roofs with Wind Tunnel Tests
- Author
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Qing Shan Yang and Bo Chen
- Subjects
Mathematics::Dynamical Systems ,General Medicine ,Mechanics ,Edge (geometry) ,Pressure coefficient ,Computer Science::Other ,Physics::Geophysics ,Vortex ,law.invention ,Physics::Fluid Dynamics ,Pressure measurement ,Skewness ,law ,Kurtosis ,Geotechnical engineering ,Roof ,Geology ,Wind tunnel - Abstract
With wind tunnel tests, simultaneous pressure measurements are made on 4 cylindrical roof models with different rise-span ratios and roof inclinations. Effects of these geometrical factors on wind pressure characteristics of the roofs are investigated, including mean pressure coefficients, RMS pressure coefficients, skewness, kurtosis, and probability distributions of wind pressure. Results show that the mean vertical wind force coefficient of high rise-span ratio roof is larger than that of the low rise-span ration roof; the mean pressure coefficient distribution of the low rise-span ratio roof is similar to that of RMS pressure coefficients and the skewness (or the kurtosis); the vortex center line occurs at the windward edge for the low rise-span ratio roof with inclination 0°, which occurs at the roof apex for the high rise-span ratio roof. The roof inclination has more effects on the low rise-span ratio roof, the vortex moves from the windward edge to the apex for the roof with inclination 7.2°when the wind flows from the low eave to the high eave. The distribution of the skewness is strongly correlative to that of the kurtosis. The probability distributions of the roof edges and corners deviate obviously from the Guass distribution. If this point is ignored, the peak suction pressure will be underestimated.
- Published
- 2013
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33. Microstructure and mechanical behaviour of asymmetric extruded Mg–3Al–1Zn alloy sheets
- Author
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Fu Sheng Pan, Bin Jiang, Q Xiang, Jiahong Dai, and Qing Shan Yang
- Subjects
Chamfer ,Materials science ,business.product_category ,Mechanical Engineering ,Metallurgy ,Alloy ,engineering.material ,Condensed Matter Physics ,Microstructure ,Mechanics of Materials ,engineering ,Die (manufacturing) ,Formability ,General Materials Science ,Extrusion ,Texture (crystalline) ,Magnesium alloy ,business - Abstract
Microstructural evolution and mechanical responses of Mg–3Al–1Zn (AZ31) sheet processed by the asymmetric extrusion (ASE) and conventional extrusion (CE) are examined. Mechanical properties of ASE sheets were remarkably enhanced compared with CE samples. This is attributed to the subdivision of the asymmetric extrusion die along the flow passage equipped with a chamfer on one side, which would trigger the angular spread of the basal texture by introducing an asymmetry shear deformation. Moreover, subsequent annealed ASE specimens show a significant weakening of the basal texture and a combination of the superior stretch formability.
- Published
- 2013
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34. Effect of Al2Ca Compound on Microstructure of As-Cast AZ31 and AZ61 Alloys
- Author
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Bin Jiang, Qing Shan Yang, Xiao Ke Li, Xiao-yong Huang, and Fu Sheng Pan
- Subjects
Materials science ,Mechanics of Materials ,Mechanical Engineering ,Metallurgy ,Alloy ,Nucleation ,Intermetallic ,engineering ,General Materials Science ,engineering.material ,Condensed Matter Physics ,Microstructure ,AZ31 alloy - Abstract
The inoculation effect of Al2Ca intermetallic compound on microstructure evolution was examined performed on as-cast AZ31 and AZ61 alloys. The refinement mechanism of Mg-Al alloys was discussed with the Miedema model and edge-to-edge matching model. Al2Ca compound has a good crystallographic matching relation with Mg matrix, which formed in the solidification process. It is considered that Al2Ca can act as a potential and effective heterogeneous nucleation center. The results reveal that the grain refinement effect of Al2Ca compound has more pronounced in AZ31 alloy compared with in AZ61 alloy.
- Published
- 2013
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35. [Evolution and transition of source of Patrinia Herba and Patrinia Radix]
- Author
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Ying-Long, Xiang, Gui-Lin, Mei, Han, Luo, Wen-Tao, Fang, Hua-Sheng, Peng, Cheng-Wu, Feng, Qing-Shan, Yang, Xiang-Yu, Li, and Yan-Peng, Zhang
- Subjects
Patrinia ,China ,Plants, Medicinal ,Medicine, Chinese Traditional ,Plant Roots ,History, Ancient ,Drugs, Chinese Herbal - Abstract
Both Patrinia Herba and Patrinia Radix are traditional Chinese herbal medicines. The herbal source and medicinal part of them are confusing in the herbal medicine market of China. To explore the evolution and transition of the herbal source and medicinal part of Patrinia Herba and Patrinia Radix, this paper systematically summarizes the record of the herbal source and medicinal part of them in ancient classics of herbal medicine in China. According to the findings, before Ming Dynasty, Patrinia Herba originated from the radix of the plants with yellow flowers of Patrinia. In Ming and Qing Dynasty, Patrinia Herba originates from the whole plant (including the radix)of the plant with white flowers of Patrinia. In Ming Dynasty, Patrinia Radix, stemming from the radix of the plants with yellow flowers of Patrinia, started to be used as a traditional Chinese herbal medicine, which had the same herbal source with that of Patrinia Herba before Ming Dynasty. Therefore, Patrinia Herba and Patrinia Radix can be seen as the same traditional Chinese herbal medicine, and the genuine of Patrinia Herba should be the radix and the whole herba of P. scabiosaefolia and P. heterophylla.
- Published
- 2017
36. On the Stochastic Dynamics of a Social Epidemics Model
- Author
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Qing-Shan Yang, Xun-Yang Wang, and Peng-Zhan Zhang
- Subjects
Continuous-time stochastic process ,Stationary distribution ,Article Subject ,Computer science ,lcsh:Mathematics ,010103 numerical & computational mathematics ,lcsh:QA1-939 ,01 natural sciences ,010101 applied mathematics ,Stochastic dynamics ,Modeling and Simulation ,Applied mathematics ,Ergodic theory ,Stochastic optimization ,0101 mathematics ,Mathematical economics - Abstract
Alcohol abuse is a major social problem, which has caused a lot of damages or hidden dangers to the individual and the society. In this paper, with random factors of alcoholism considered in mortality rate of compartment populations, we formulate a stochastic alcoholism model according to compartment theory of infectious disease. Based on this model, we investigate the long-term stochastic dynamics behaviors of two equilibria of the corresponding deterministic model and point out the effect of random disturbance on the stability of the system. We find that when R0≤1, we get the estimation between the trajectory of stochastic system and E0=(Π/μs,0,0,0) in the average in time with respect to the disturbance intensity, while when R0>1, stochastic system is ergodic and has the unique stationary distribution. Finally, we carry out numerical simulations to support the corresponding theoretical results.
- Published
- 2017
37. [Chemical constituents from fresh tubers of Dioscorea bulbifera]
- Author
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Jin-Song, Liu, Wei-Na, Gao, Juan, Zheng, Guo-Kai, Wang, and Qing-Shan, Yang
- Subjects
Plant Tubers ,Dioscorea ,Phytochemicals - Abstract
Eighteen compounds were isolated from the 95% ethanol extract of fresh tubers of Dioscorea bulbifera by column chromatography over silica gel,Sephadex LH-20, and ODS. Their structures were elucidated by spectroscopic data analysis as 6-hydroxy-2,10,10-trimethoxy-anthracen-9-one(1), diosgenin (2), stigmasterol(3), 3, 7-dimethoxy-5, 3', 4'-trihydroxyflavone(4), 2, 7-dihydroxy-3, 4-dimethoxyphenanthrene(5), 3, 7-dihydroxy-2, 4-dimethoxy phenanthrene(6), 2, 7-dihydroxy-4-methoxyphenanthrene (7), 2, 7-dihydroxy-3, 4-dimethoxy-9, 10-dihydroxy phenanthrene(8), azelaic acid (9), 8-epidiosbulbin E acetate (10), 1, 7-bis-(4-hydroxyphenyl)-4E, 6E-heptadien-3-one(11), diosbulbin B(12), pentacosanoic acid 2', 3'-dihydroxypropyl ester(13), 2, 7-dihydroxy-4-methoxy-9, 10-dihydroxy-phenanthrene (14), 1, 7-bis-(4-hydroxyphenyl)-1E, 4E, 6E-heptatrien-3-one (15), 6-ethoxy-1H-pyrimidine-2, 4-dione (16), 3, 5, 4'-trihydroxy-bibenzyl (17), and diosbulbin F (18). Compound 1 is a new compound, and compounds 7, 9, 13, and 16 were isolated from this plant for the first time.
- Published
- 2016
38. Up-Regulation of MicroRNA-133a Inhibits the MEK/ERK Signaling Pathway to Promote Cell Apoptosis and Enhance Radio-Sensitivity by Targeting EGFR in Esophageal Cancer In Vivo and In Vitro
- Author
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Qing-Shan, Yang, Li-Peng, Jiang, Chun-Yan, He, Yu-Na, Tong, and Yuan-Yuan, Liu
- Subjects
Male ,Esophageal Neoplasms ,MAP Kinase Signaling System ,Apoptosis ,Middle Aged ,Radiation Tolerance ,Neoplasm Proteins ,Up-Regulation ,ErbB Receptors ,MicroRNAs ,Cell Line, Tumor ,Humans ,Female ,RNA, Neoplasm ,Aged - Abstract
This study aims to explore how microRNA-133a (miR-133a) affects cell apoptosis and radio-sensitivity by targeting EGFR via regulating MEK/ERK pathway in esophageal cancer (EC). A total of 358 EC patients were selected and assigned into the resistant and sensitive groups. Human EC KYSE 150 cell line was assigned into the blank, negative control (NC), miR-133a mimic, miR-133a inhibitors, si-EGFR, miR-133a inhibitors + si-EGFR groups after transfection. MiR-133a and EGFR mRNA expressions were detected by qRT-PCR and EGFR, MEK/ERK pathway-related protein expressions were detected by Western blotting. The radio-sensitivity and cell apoptosis were testified by clone formation and flow cytometry. MiR-133a was up-regulated but EGFR was down-regulated in the sensitive group than in the resistant group. Compared with the blank and NC groups, the miR-133a mimic and si-EGFR groups exhibited increased cell apoptosis rate but decreased EGFR, p-MEK1/2, and p-ERK1/2 protein expressions; while opposite trend was observed in the miR-133a inhibitors group. Compared with the miR-133a inhibitors group, the miR-133a inhibitors + si-EGFR group presented reduced cell survival rate, EGFR, p-MEK1/2, and p-ERK1/2 protein expressions but increased cell apoptosis rate. These results indicated that miR-133a could inhibit the MEK/ERK pathway to promote cell apoptosis and enhance radio-sensitivity by targeting EGFR in EC. J. Cell. Biochem. 118: 2625-2634, 2017. © 2017 Wiley Periodicals, Inc.
- Published
- 2016
39. ChemInform Abstract: Abietane Diterpenoids from Caryopteris incana (Thunb.) Miq
- Author
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Sen-Miao Zhao, Wei Wang, Qing-Shan Yang, Jian-Li Zhou, and Gui-Xin Chou
- Subjects
Terpene ,Caryopteris incana ,chemistry.chemical_compound ,chemistry ,Stereochemistry ,Ic50 values ,General Medicine ,Two-dimensional nuclear magnetic resonance spectroscopy ,In vitro ,Human cancer ,Dipeptidyl peptidase ,Abietane - Abstract
Twelve new diterpenes, caryopincaolide A-L (1-4, 11-12, 16-19, 27-28), together with twenty-eight known diterpenes, have been isolated from the whole plant of Caryopteris incana (Thunb.) Miq. Their structures were elucidated on the basis of 1D and 2D NMR, IR, X-ray crystal diffraction and mass spectroscopic data, as well as ECD calculations. All compounds were tested for in vitro dipeptidyl peptidase IV (DPP-IV) inhibitory activity, with compounds 3, 4, 28, 29, and 40 exhibiting DPP-IV inhibitory effects with IC50 values ranging from 54.2 to 228.9 μM. Compounds 1, 3 and 4 also showed potent activity toward the inhibition of the growth of human cancer cells and 1 can induce apoptosis in Hey and A-549 cells.
- Published
- 2016
- Full Text
- View/download PDF
40. [Development of rapid setting-drying device for herbarium specimens and its application in survey of Chinese materia medica resources in Anhui]
- Author
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Zheng Han, Li Chuanrun, Sun Xiaomei, Xiang Long, Jian-Li Zhou, He-Ling Liu, Dai-Yin Peng, Wei-Bo Zhao, Qing-Shan Yang, and Tao Xu
- Subjects
Engineering ,Plants, Medicinal ,business.industry ,Materia medica ,Library science ,Specimen Handling ,Herbarium ,Complementary and alternative medicine ,Surveys and Questionnaires ,Materia Medica ,Pharmacology (medical) ,General Pharmacology, Toxicology and Pharmaceutics ,Desiccation ,Medicine, Chinese Traditional ,business ,Drugs, Chinese Herbal - Abstract
Herbarium specimens are the basis for the plant classification and indispensable media in teaching, scientific research and resources investigation. They have also played an important role in identifying and producing traditional Chinese medicine. High-quality herbarium specimens shall meet high requirements for integrity, smoothness, color and fabricating efficiency. Therefore, we designed a rapid setting and drying device for herbarium specimens, which could make the herbarium specimens smooth, colorful and not easy to mildew. In this paper, we pointed out the deficiency of traditional methods in making herbarium specimens, and introduced the structure and working principle of the device. Besides, we also discussed the effect of the device in setting and drying herbarium specimens and its application in the fourth national survey of the Chinese material medica resources (CMMR) in Anhui province. As a result, the device provides new ideas for producing herbarium specimens, with a reasonable design, good uniformity, high efficiency, safety and portability, and so is worthy of promotion and application in the national survey of CMMR.
- Published
- 2016
41. Characteristics of resistivity log response of oil layers under polymer flooding
- Author
-
Yu Jun, Qing-Shan Yang, and Bao-Zhi Pan
- Subjects
chemistry.chemical_classification ,Materials science ,Polymer flooding ,Core (manufacturing) ,Polymer ,Geophysics ,Fresh water ,chemistry ,Electrical resistivity and conductivity ,Polymer solution ,Geotechnical engineering ,Composite material ,Displacement (fluid) ,Layer (electronics) - Abstract
Resistivity log responses are different when the oil layers is filled by a polymer solution or water and it seriously affects the log interpretation of the water flooded layer. In this paper, we first analyze the electrical properties of the polymer solution. Then, according to the different processes for polymer flooding the reservoir, we perform rock resistivity experiments and analyze the rock resistivity variations in different displacement phases. We also compare the resistivity log responses of oil layers filled with the polymer solution to those filled with water. The results show that when displacing the oil-bearing core by different polymers, the resistivity changes monotonously decrease and show either “W” type or “S” type. The resistivity log responses are weak when displacing water and there is no flooded show if the oil layer is injected by a fresh water polymer solution. If the oil layer is injected by a sewage polymer solution, the resistivity log response has similar characteristic as a polluted water flooded layer.
- Published
- 2012
- Full Text
- View/download PDF
42. Application Research of White Mud in 660 MW Unit FGD System
- Author
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Yong Jin Liao, Yu Jia Wang, and Qing Shan Yang
- Subjects
Pollution ,Gypsum ,Waste management ,media_common.quotation_subject ,General Engineering ,Alkalinity ,engineering.material ,Dewatering ,Flue-gas desulfurization ,chemistry.chemical_compound ,Calcium carbonate ,Wastewater ,chemistry ,engineering ,Slurry ,Environmental science ,media_common - Abstract
White mud is generally known as the residue of soda ash production by ammonia-soda process. The treatment of it has been one problem in soda ash industry due to the large amount of production, strong alkalinity and corrosiveness. In China, the treatment of white mud is stacking currently, which not only occupying land but also causing environment pollution. The main composition of it is the calcium carbonate. If white mud replaces the limestone as the desulfurization agent in wet Flue Gas Desulfurization (W-FGD) system, it can attain the goal of treating the waste with another, achieve the circular economy between enterprises, and reduce the desulfurization cost significantly. In this paper, the research of white mud in 660 MW Unit W-FGD systems was investigated. Study shows that the properties of white mud and limestone are significantly different. Because of smaller particle size and active MgO, the alkaline and reaction activity of white mud are better than that of limestone, results to higher desulfurization rate and lower running cost. However, the purity of white mud is lower because of CaSO4, Cl-, and other impurities, so the dewatering system of gypsum needs to increase output by about 17%; the output of the slurry feed system needs to be increased by about 30%; the discharge capacity of wastewater needs to be increased by about 23 t/h.
- Published
- 2012
- Full Text
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43. Methotrexate-mediated inhibition of RAD51 expression and homologous recombination in cancer cells
- Author
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Liqing Du, Xiao-Qing Du, Yan Wang, Qing-Shan Yang, Peng Zhao, Feiyue Fan, Qiang Liu, Jian-Qiang Bai, Hong Wang, and Xiao-Chun Wang
- Subjects
Antimetabolites, Antineoplastic ,Cancer Research ,DNA End-Joining Repair ,DNA repair ,Genes, BRCA2 ,RAD51 ,Down-Regulation ,Biology ,Homology directed repair ,chemistry.chemical_compound ,Cell Line, Tumor ,Neoplasms ,Humans ,RNA, Small Interfering ,Homologous Recombination ,Recombinational DNA Repair ,General Medicine ,DNA repair protein XRCC4 ,Molecular biology ,Rad52 DNA Repair and Recombination Protein ,Gene Expression Regulation, Neoplastic ,Non-homologous end joining ,Methotrexate ,Oncology ,chemistry ,Cancer cell ,Cancer research ,Rad51 Recombinase ,Homologous recombination ,DNA - Abstract
Methotrexate is an inhibitor of folic acid metabolism. Homologous recombination is one of the most important ways to repair double-stranded breaks in DNA and influence the radio- and chemosensitivity of tumor cells. But the relationship between methotrexate and homologous recombination repair has not been elucidated.Induction of double-strand breaks by methotrexate in HOS cells is assessed by the neutral comet assay. Inhibition of subnuclear repair foci by methotrexate is measured by immunofluorescence. Western blot and quantitative real-time PCR are conducted to detect whether methotrexate affects the expression level of genes involved in homologous recombination. In addition, we used a pCMV3xnls-I-SceI construct to determine whether methotrexate directly inhibits the process of homologous recombinational repair in cells, and the sensitivity to methotrexate in the Ku80-deficient cells is detected using clonogenic survival assays.The result showed that methotrexate can regulate the repair of DNA double-strand breaks after radiation exposure, and methotrexate inhibition caused the complete inhibition of subnuclear repair foci in response to ionizing radiation. Mechanistic investigation revealed that methotrexate led to a significant reduction in the transcription of RAD51 genes. Treatment with methotrexate resulted in a decreased ability to perform homology-directed repair of I-SceI-induced chromosome breaks. In addition, enhancement of cell death was observed in Ku mutant cells compared to wild-type cells.These results demonstrate that methotrexate can affect homologous recombination repair of DNA double-strand breaks by controlling the expression of homologous recombination-related genes and suppressing the proper assembly of homologous recombination-directed subnuclear foci.
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- 2012
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44. Investigation on the Effect of Infilled Walls Utilizing Response Spectrum Analysis for Steel Staggered-Truss System
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Qing Shan Yang and Qing Sheng Guo
- Subjects
Engineering ,business.industry ,Shear force ,Seismic loading ,Stiffness ,Truss ,Torsion (mechanics) ,General Medicine ,Structural engineering ,3d simulation ,Finite element method ,medicine ,Geotechnical engineering ,medicine.symptom ,business ,Response spectrum - Abstract
Considering the structure type of the steel staggered-truss (SST) system, the effect of infilled walls will be major and need to be studied amply, some scientific design regulations need to be found for referrence. Based on two different 3D models considering or ignoring the stiffness of infilled walls (SIW), a numerical investigation is presented on the structural behaviors of the SST system utilizing the finite element 3D simulation analysis soft ware ETABS. The longitudinal structure is asymmetrical due to the SIW, it causes the torsion forces in the building. Comparing to the different results of response spectrum analysis, including storey drift and equivalent base shear under frequent earth quake and rare earth quake, some conclusions were made, including the capacity of the SST system under seismic load and the effect of the SIW for SST system. The increased base shear force factors due to the effect of the SIW were suggested for SST structure design, it is different from the other steel structure types.
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- 2012
- Full Text
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45. Investigation on Steel Staggered-Truss System RC Slab
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Qing Shan Yang and Qing Sheng Guo
- Subjects
Engineering ,business.industry ,General Engineering ,Truss ,Stiffness ,3d model ,Structural engineering ,Finite element method ,medicine ,Slab ,Geotechnical engineering ,medicine.symptom ,business ,Response spectrum ,Beam (structure) ,Stress concentration - Abstract
For steel staggered-truss (SST) system, RC slabs are the main structure members to make the whole building work together beside to take the vertical load. There are openings in the RC slabs due to requirement of staircases、lift wells and other services, these openings will reduce the stiffness of RC slab and make stress concentration. Usually, the RC slab is designed under vertical load only, this will lead to the design defect and building calapse for SST structure. There are few research for SST RC slab are presented untill now. In the paper, based on two different 3D models considering or ignoring the stiffness of infilled walls (SIW), a numerical investigation is presented on the structural behaviors of the SST system utilizing the soft ware ETABS. As a finite element analysis method, the shell element is adopted for RC slab & infilled wall, the beam element is adopted for beam、colum and truss members. The structure is asymmetrical due to the SIW, it causes the torsional forces in the building and the extra stresses in the RC slabs, the additional reinforcement need to be provided to strengthen the high stress areas. Comparing with the results of response spectrum analysis under the combination with earth quake load, we make some conclusions, including the capacity of anti-seismic and the effect of the SIW for SST system RC slab,that could be a reference for SST structure design.
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- 2012
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46. Dynamic Time History Analysis of the Effect of Infilled Walls on the Steel Staggered-Truss System
- Author
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Qing Shan Yang and Qing Sheng Guo
- Subjects
Quake (natural phenomenon) ,Engineering ,business.industry ,Shear force ,Rare earth ,General Engineering ,Stiffness ,Truss ,Structural engineering ,3d simulation ,Finite element method ,Time history ,medicine ,Geotechnical engineering ,medicine.symptom ,business - Abstract
A structure with steel staggered-truss (SST) system is numerically investigated in this paper, utilizing the finite element 3D simulation analytial soft ware ETABS. Two different 3D models considering or ignoring the stiffness of infilled walls (SIW) are analyzed with Dynamic Time History method including storey drift and equivalent base shear force under frequent earth quake and rare earth quake. Results indicate that the effect of the SIW is prominent and should be considered.
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- 2012
- Full Text
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47. Analysis of Mechanical Performance Considering Damage Accumulation of Intersecting Joints in Steel Structures
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Qing Shan Yang, Bao Feng Fan, Leroy Gardner, and Na Yang
- Subjects
Stress (mechanics) ,Engineering ,Chord (geometry) ,Buckling ,business.industry ,Steel structures ,Steel tube ,General Medicine ,Structural engineering ,business - Abstract
The mechanical behaviors of intersecting joints considering damage accumulation in steel tube structures is analyzed through the FE-program ABAQUS. The stress characteristic and failure modes of these joints are concluded. Especially, it has been analyzed influence of the change of geometric parameters to mechanical behavior of joints. Finally, the results indicate the joints have a good mechanical performance and good plastic deformation as to excessive local buckling of chord under the loads.
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- 2011
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48. Multi-Object Resonant Response Equivalent Static Wind Load of Large-Span Roofs
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Qing Shan Yang, Yu Ji Tian, and Yu Xue Li
- Subjects
Engineering ,business.industry ,General Medicine ,Structural engineering ,Response control ,business ,Object (computer science) ,Span (engineering) ,Roof ,Wind engineering ,Strain energy - Abstract
According to the strain energy equivalent, the resonant response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load for large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to resonant equivalent static wind load analysis of 2008 Beijing Olympic Tennis Center Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.
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- 2011
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49. Background Response Equivalent Static Wind Load of Large-Span Roofs Based on Energy Equation
- Author
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Qing Shan Yang, Yu Ji Tian, and Yu Xue Li
- Subjects
Engineering ,business.industry ,Energy equation ,General Medicine ,Structural engineering ,Response control ,business ,Span (engineering) ,Roof ,Wind engineering ,Strain energy - Abstract
Based on strain energy equivalent, the background response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load of large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to background equivalent static wind load analysis of China National Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.
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- 2011
- Full Text
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50. Aerodynamic Comfort Analysis of High-Speed Trains Passing each other at the same Speed through a Tunnel
- Author
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Qing Shan Yang, Ya Guang Yan, and Jian Zhang
- Subjects
Engineering ,Finite volume method ,business.industry ,Turbulence ,Mechanical engineering ,Transient pressure ,General Medicine ,Aerodynamics ,Mechanics ,Midpoint ,Compressibility ,Train ,Point (geometry) ,business - Abstract
On the basis of the three-dimensional,compressible,unsteady-state,viscous N-S Equation and k-ε turbulence model,the simulation calculation is made with the finite volume method on the aerodynamic effect of two high-speed trains passing each other at the same speed through a tunnel,simulating the pressure change,analysising regularity of the pressure,researching comfort in the train.The following conclusions have been drawn from research:The maximum of transient pressure is concerned with the meeting point,when the two high-speed trains meet in tunnel.When the length,the speed and the sealing factor of the train are same,the transient pressure is maximum with the trains meeting at the midpoint of tunnel.When the tunnel length,the speed of the train,the sealing factor and the point of meeting are same,the transient pressure of the longer train is maximum.When the sealing factor is greater than 15s,the standard of permissible pressure (1250Pa\3s) can be satisfied with all circumstances.
- Published
- 2011
- Full Text
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