A New Composite Truss Bridge and a Study on Its Dynamic Characteristics with FE and Experimental Methods

Xiaoli Xie,Yang Huang,Xia Qin 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.3

Improvements to the dynamic characteristics and stiffness of composite girder bridges are necessary to expand their applications and capabilities. The natural frequency of a bridge directly reflects the dynamic characteristics of a structure. From the calculation principle for the natural frequency, the natural frequencies of a bridge can be significantly increased if the load increases slightly while the structural stiffness increases significantly. Based on this, a new type of concrete-steel composite truss bridge is proposed. The new bridge has a reasonable new arrangement for the position of the concrete and steel, according to the bending moment law for continuous girders. The mechanical analysis of the new bridge shows that it has the characteristic of adding a small amount of load at a reasonable position, which can significantly improve the stiffness. Therefore, it is possible to achieve the purpose of improving the dynamic characteristics so that they are far better than those of a conventional composite truss bridge. To further study the dynamic characteristics of the new composite truss bridge, the finite element (FE) method was used to analyse the new bridges, and the results are compared with those of conventional composite truss bridges. Furthermore, several parameters that influence the dynamic characteristics of the new composite truss bridge were studied. Finally, the dynamic characteristics of the small-span new bridge were studied by finite element analysis (FEA) and experiment. The results show that the new composite truss bridges with different span arrangements and different second-stage dead loads always have better natural frequencies and stiffness advantages. Therefore, the new composite truss bridge is suitable for girder bridges with strict requirements for their stiffness and dynamic characteristics, especially for super-long span high-speed railway girder bridges.

Mechanical Properties and Experimental Study of a New Laminated Girder Single Tower Cable-Stayed Bridge

Xiaoli Xie,Haolin Su,Mulin Pang 한국강구조학회 2023 International Journal of Steel Structures Vol.23 No.3

With the span of steel truss girder cable-stayed bridge (STGCB) increases, it is easy to have local stability problems caused by the increase of axial forces, and the whole steel truss girder uses a large amount of steel. To solve these problems, a new laminated girder single tower cable-stayed bridge (NLGCB) is proposed in this paper. The structure of NLGCB is similar to STGCB, the difference is that the lower chords of the main girder near the cable tower are changed into the concrete structure, while the web members and upper chords are made of steel. Thus, a new type of concrete-steel laminated girder is formed, so as to improve the stress characteristics of the main girder. In order to verify the superiority of mechanical properties of NLGCB, a test bridge with an unequal span (5 m + 6 m) was constructed. The natural frequency of the first in-plane vibration of the bridge was measured by the pulsation test, and the stresses and deflections of the structure were tested by the static load test. The static and dynamic characteristics of a 300 m + 300 m span bridge were analyzed by finite element software and compared with STGCB. The results show that the natural frequency of the first in-plane vibration of the structure is close to the calculated value, and the vibration modes are consistent with the finite element simulation ones. When the steel consumption is reduced by 13.7% and the concrete consumption is not much, the strength, stiffness, natural vibration frequency, and stability of the structure are greatly improved.

Decomposition and Reconstruction of Protein Sequences: The Problem of Uniqueness and Factorizable Langauge

Xiaoli Shi,Bailin Hao,Huimin Xie,Shuyu Zhang 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.50 No.1I

In our attempt to justify the CVTree approach of inferring phylogenetic relationship among bacteria from their complete genomes without using sequence alignment, we encountered the problem of the uniqueness of the reconstruction of a protein sequence from its constituent K-peptides, which has a natural relation to a well-understood problem in graph theory, namely, the number of Eulerian loops in a graph. The existence of finite state automata to recognize the uniqueness of a sequence reconstruction provides us with yet another application of factorizable language, which was elucidated at a previous Dynamics Days Asia Pacific meeting (DDAP1).

Selection of High Laccase-Producing Coriolopsis gallica Strain T906: Mutation Breeding, Strain Characterization, and Features of the Extracellular Laccases

( Xiaoli Xu ),( Lei Feng ),( Zhenya Han ),( Sishi Luo ),( Ai`min Wu ),( Jun Xie ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.9

Commercial application of laccase is often hampered by insufficient enzyme stocks, with very low yields obtained from natural sources. This study aimed to improve laccase production by mutation of a Coriolopsis gallica strain and to determine the biological properties of the mutant. The high-yield laccase strain C. gallica TCK was treated with N-methyl-N-nitro Nnitrosoguanidine and ultraviolet light. Among the mutants isolated, T906 was found to be a high-production strain of laccases. The mutant strain T906 was stabilized via dozens of passages, and the selected ones were further processed for optimization of metallic ion, inducers, and nutritional requirements, which resulted in the optimized liquid fermentation medium MF9. The incubation temperature and pH were optimized to be 30°C and 4.5, respectively. The mutant strain T906 showed 3-times higher laccase activity than the original strain TCK under optimized conditions, and the maximum laccase production (303 U/ml) was accomplished after 13 days. The extracellular laccase isoenzyme 1 was purified and characterized from the two strains, respectively, and their cDNA sequence was determined. Of note, the laccase isoenzyme 1 transcription levels were overtly increased in T906 mycelia compared with values obtained for strain TCK. These findings provide a basis for C. gallica modification for the production of high laccase amounts.

Methods of Improving the Natural Vibration Characteristics of the Through Tied-Arch Bridge and Test Verification

Chen Qiu,Xiaoli Xie,Chuangjie Yang,Xia Qin,Mulin Pang 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.1

A through tied-arch bridge with multi-point elastic constraints (MTAB) is proposed based on the truss structure concept to improve the natural vibration characteristics of the conventional through tied-arch bridge (CTAB). Rigid inclined rods are added between the main beam and arch ribs to form an integral truss structure with arch ribs as upper chords, rigid inclined rods as web members, and the main beam as a bottom chord to increase the rigidity of the structure. Through timely system transformation, arch ribs bear all dead loads and the integral truss structure bears all the live loads so that the advantages of arch ribs and web members are maximized. The pulsation test and fi nite element analysis (FEA) were carried out to verify the superiority of the natural vibration characteristics of the MTAB based on a 50 m span test bridge. Taking a 350 m span arch bridge as an example, the natural vibration characteristics and other mechanical characteristics of the MTAB were studied and compared with that of the CTAB. The results show the MTAB has better mechanical properties and economy, especially natural vibration characteristics and stiff ness.

Impaired Na+ −K+-ATPase signaling in renal proximal tubule contributes to hyperuricemia-induced renal tubular injury

Jing Xiao,Xiaoli Zhang,Chensheng Fu,Qingmei Yang,Ying Xie,Zhenxing Zhang,Zhibin Ye 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Hyperuricemia contributes to renal inflammation. We aimed to investigate the role of Na+–K+–ATPase (NKA) in hyperuricemiainduced renal tubular injury. Human primary proximal tubular epithelial cells (PTECs) were incubated with uric acid (UA) at increasing doses or for increasing lengths of time. PTECs were then stimulated by pre-incubation with an NKA α1 expression vector or small interfering RNA before UA (100 μg ml−1, 48 h) stimulation. Hyperuricemic rats were induced by gastric oxonic acid and treated with febuxostat (Feb). ATP levels, the activity of NKA and expression of its α1 subunit, Src, NOD-like receptor pyrin domain-containing protein 3 (NLRP3) and interleukin 1β (IL-1β) were measured both in vitro and in vivo. Beginning at concentrations of 100 μg ml−1, UA started to dose-dependently reduce NKA activity. UA at a concentration of 100 μg ml−1 time-dependently affected the NKA activity, with the maximal increased NKA activity at 24 h, but the activity started to decrease after 48 h. This inhibitory effect of UA on NKA activity at 48 h was in addition to a decrease in NKA α1 expression in the cell membrane, but an increase in lysosomes. This process also involved the subsequent activation of Src kinase and NLRP3, promoting IL-1β processing. In hyperuricemic rats, renal cortex NKA activity and its α1 expression were upregulated at the 7th week and both decreased at the 10th week, accompanied with increased renal cortex expression of Src, NLRP3 and IL-1β. The UA levels were reduced and renal tubular injuries in hyperuricemic rats were alleviated in the Feb group. Our data suggested that the impairment of NKA and its consequent regulation of Src, NLRP3 and IL-1β in the renal proximal tubule contributed to hyperuricemia-induced renal tubular injury.

ssc-miR-185 targets cell division cycle 42 and promotes the proliferation of intestinal porcine epithelial cell

Wang, Wei,Wang, Pengfei,Xie, Kaihui,Luo, Ruirui,Gao, Xiaoli,Yan, Zunqiang,Huang, Xiaoyu,Yang, Qiaoli,Gun, Shuangbao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: microRNAs (miRNAs) can play a role in a variety of physiological and pathological processes, and their role is achieved by regulating the expression of target genes. Our previous high-throughput sequencing found that ssc-miR-185 plays an important regulatory role in piglet diarrhea, but its specific target genes and functions in intestinal porcine epithelial cell (IPEC-J2) are still unclear. We intended to verify the target relationship between porcine miR-185 and cell division cycle 42 (CDC42) gene in IPEC-J2 and to explore the effect of miR-185 on the proliferation of IPEC-J2 cells. Methods: The TargetScan, miRDB, and miRanda software were used to predict the target genes of porcine miR-185, and CDC42 was selected as a candidate target gene. The CDC42-3' UTR-wild type (WT) and CDC42-3'UTR-mutant type (MUT) segments were successfully cloned into pmirGLO luciferase vector, and the luciferase activity was detected after co-transfection with miR-185 mimics and pmirGLO-CDC42-3'UTR. The expression level of CDC42 was analyzed using quantitative polymerase chain reaction and Western blot. The proliferation of IPEC-J2 was detected using cell counting kit-8 (CCK-8), methylthiazolyldiphenyl-tetrazolium bromide (MTT), and 5-ethynyl-2'-deoxyuridine (EdU) assays. Results: Double enzyme digestion and sequencing confirmed that CDC42-3'UTR-WT and CDC42-3'UTR-MUT were successfully cloned into pmirGLO luciferase reporter vector, and the luciferase activity was significantly reduced after co-transfection with miR-185 mimics and CDC42-3'UTR-WT. Further we found that the mRNA and protein expression level of CDC42 were down-regulated after transfection with miR-185 mimics, while the opposite trend was observed after transfection with miR-185 inhibitor (p<0.01). In addition, the CCK-8, MTT, and EdU results demonstrated that miR-185 promotes IPEC-J2 cells proliferation by targeting CDC42. Conclusion: These findings indicate that porcine miR-185 can directly target CDC42 and promote the proliferation of IPEC-J2 cells. However, the detailed regulatory mechanism of miR-185/CDC42 axis in piglets' resistance to diarrhea is yet to be elucidated in further investigation.

Fe3+-binding transferrin nanovesicles encapsulating sorafenib induce ferroptosis in hepatocellular carcinoma

Youmei Xiao,Zhanxue Xu,Yuan Cheng,Rufan Huang,Yuan Xie,Hsiang‑i Tsai,Hualian Zha,Lifang Xi,Kai Wang,Xiaoli Cheng,Yanfeng Gao,Changhua Zhang,Fang Cheng,Hongbo Chen 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background Ferroptosis, iron-dependent cell death, is an established mechanism for cancer suppression, particularly in hepatocellular carcinoma (HCC). Sorafenib (SOR), a frontline drug for the treatment of HCC, induces ferroptosis by inhibiting the Solute Carrier family 7 member 11 (SLC7A11), with inadequate ferroptosis notably contributing to SOR resistance in tumor cells. Methods To further verify the biological targets associated with ferroptosis in HCC, an analysis of the Cancer Genome Atlas (TCGA) database was performed to find a significant co-upregulation of SLC7A11 and transferrin receptor (TFRC), Herein, cell membrane-derived transferrin nanovesicles (TF NVs) coupled with Fe3+ and encapsulated SOR (SOR@TF-Fe3+ NVs) were established to synergistically promote ferroptosis, which promoted the iron transport metabolism by TFRC/TF-Fe3+ and enhanced SOR efficacy by inhibiting the SLC7A11. Results In vivo and in vitro experiments revealed that SOR@TF-Fe3+ NVs predominantly accumulate in the liver, and specifically targeted HCC cells overexpressing TFRC. Various tests demonstrated SOR@TF-Fe3+ NVs accelerated Fe3+ absorption and transformation in HCC cells. Importantly, SOR@TF-Fe3+ NVs were more effective in promoting the accumulation of lipid peroxides (LPO), inhibiting tumor proliferation, and prolonging survival rates in HCC mouse model than SOR and TF- Fe3+ NVs alone. Conclusions The present work provides a promising therapeutic strategy for the targeted treatment of HCC.

Visible light photocatalytic removal performance and mechanism of diclofenac degradation by Ag3PO4 sub-microcrystals through response surface methodology

Jianfeng Gou,Qiuling Ma,Yuqi Cui,Xiaoyong Deng,Huixuan Zhang,Xiuwen Cheng,Xiaoli Li,Mingzheng Xie,Qingfeng Cheng,Huiling Liu 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.49 No.-

In this study, high visible light response and charge separation efficiency of body-centered cubic Ag3PO4sub-microcrystals were fabricated through ultrasound-precipitation process. Additionally, the parameterswere optimized by photocatalytic (PC) removal degradation of diclofenac based on response surfacemethodology. Results indicated that the PC removal efficiency of diclofenac was significantly affected byAg3PO4 content and pH value. Under the optimized conditions, 99.9% of diclofenac could be degradedwithin 16 min Xenon illumination. Furthermore, three PC removal degradation pathways of diclofenacwere proposed, including OH-adduct to aromatic ring, direct oxidation by photoinduced holes anddecarboxylation of side chain from the parent compound.

Fabrication of platinum nano-crystallites decorated TiO2 nano-tube array photoelectrode and its enhanced photoelectrocatlytic performance for degradation of aspirin and mechanism

Yuqi Cui,Qi Meng,Xiaoyong Deng,Qiuling Ma,Huixuan Zhang,Xiaoli Li,Mingzheng Xie,Qingfeng Cheng,Xiuwen Cheng 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.43 No.-

In this study, Pt NCs/TiO2 NTAs photoelectrode was fabricated through anodization process, followed byrecycle pulse electrodeposition strategy. Subsequently, physicochemical properties of the resultingsamples were studied systematically. Results indicated that Pt NCs/TiO2 NTAs photoelectrode exhibitedintense light absorbance both in the UV and visible region, high transient photocurrent density of0.089 mA cm 2 and open circuit potential of 0.275 V cm 2. In addition, 98.3% of aspirin could beeliminated within 4 h Xenon illumination with the help of +0.4 V potential. Furthermore, it can beconcluded that two tentative pathways for PEC degradation of aspirin were proposed and confirmed.