Deformation and stress behavior analysis of high concrete dam under the effect of reservoir basin deformation

Dongjian Zheng,Yanxin Xu,Meng Yang,Hao Gu,Huaizhi Su,Xinbo Cui,Erfeng Zhao 사단법인 한국계산역학회 2016 Computers and Concrete, An International Journal Vol.18 No.6

According to deformation data measured in some high concrete dams, for dam body deformation, there is a complex relationship with dam height and water head for different projects, instead of a simple monotonic relationship consistently. Meanwhile, settlement data of some large reservoirs exhibit a significant deformation of reservoir basin. As water conservancy project with high concrete dam and large storage capacity increase rapidly these decades, reservoir basin deformation problem has gradually gained engineers’ attentions. In this paper, based on conventional analytical method, an improved analytical method for high concrete dam is proposed including the effect of reservoir basin deformation. Though establishing FEM models of two different scales covering reservoir basin and near dam area respectively, influence of reservoir basin on dam body is simulated. Then, forward and inverse analyses of concrete dam are separately conducted with conventional and proposed analytical methods. And the influence of reservoir basin deformation on dam working behavior is evaluated. The results of two typical projects demonstrate that reservoir basin deformation will affect dam deformation and stress to a certain extent. And for project with large and centralized water capacity ahead of dam site, the effect is more significant than those with a slim-type reservoir. As a result, influence of reservoir basin should be taken into consideration with conducting analysis of high concrete dam with large storage capacity.

125I Seed Permanent Implantation as a Palliative Treatment for Stage III and IV Hypopharyngeal Carcinoma

Lei Li,Jie Yang,Xiaojiang Li,Xiaoli Wang,Yanxin Ren,Jimin Fei,Yan Xi,Ruimei Sun,Jing Ma 대한이비인후과학회 2016 Clinical and Experimental Otorhinolaryngology Vol.9 No.3

Objectives. The aim of this study was to investigate the feasibility and safety of percutaneous 125I seed permanent implantation for advanced hypopharyngeal carcinoma from toxicity, tumor response, and short-term outcome. Methods. 125I seeds implant procedures were performed under computed tomography for 34 patients with advanced hypopharyngeal carcinoma. We observed the local control rate, overall survival, and acute or late toxicity rate. Results. In the 34 patients (stage III, n=6; stage IV, n=28), the sites of origin were pyriform sinus (n=29) and postcricoid area (n=5). All patients also received one to four cycles of chemotherapy after seed implantation. The post-plan showed that the actuarial D90 of 125I seeds ranged from 90 to 158 Gy (median, 127 Gy). The mean follow-up was 12.3 months (range, 3.4 to 43.2 months). The local control was 2.1–31.0 months with a median of 17.7 months (95% confidence interval [CI], 13.4 to 22.0 months). The 1-, 2-, and 3-year local controls were 65.3%, 28.6%, and 9.5% respectively. Twelve patients (35%) died of local recurrence, fourteen patients (41%) died of distant metastases, and three patients (9%) died of recurrence and metastases at the same time. Five patients (15%) still survived to follow-up. At the time of analysis, the median survival time was 12.5 months (95% CI, 9.5 to 15.4 months). The 1-, 2-, and 3-year overall survival rates were 55.2%, 20.3%, and 10.9%, respectively. Five patients (15%) experienced grade 3 toxic events and nine patients (26%) have experienced grade 2 toxic events. Conclusion. This review shows relatively low toxicity for interstitial 125I seed implantation in the patients with advanced stage hypopharyngeal cancer. The high local control results suggest that 125I seed brachytherapy implant as a salvage or palliative treatment for advanced hypopharyngeal carcinoma merit further investigation.

Silicate Ions Derived from Calcium Silicate Extract Decelerate Ang II-Induced Cardiac Remodeling

Li Xin,Zhang Yanxin,Jin Qishu,Song Qiaoyu,Fan Chen,Jiao Yiren,Yang Chen,Chang Jiang,Dong Zhihong,Que Yumei 한국조직공학과 재생의학회 2023 조직공학과 재생의학 Vol.20 No.5

BACKGROUND: Pathological cardiac hypertrophy is one of the main activators of heart failure. Currently, no drug can completely reverse or inhibit the development of pathological cardiac hypertrophy. To this end, we proposed a silicate ion therapy based on extract derived from calcium silicate (CS) bioceramics for the treatment of angiotensin II (Ang II) induced cardiac hypertrophy. METHODS: In this study, the Ang II induced cardiac hypertrophy mouse model was established, and the silicate ion extract was injected to mice intravenously. The cardiac function was evaluated by using a high-resolution Vevo 3100 small animal ultrasound imaging system. Wheat germ Agglutinin, Fluo4-AM staining and immunofluorescent staining was conducted to assess the cardiac hypertrophy, intracellular calcium and angiogenesis of heart tissue, respectively. RESULTS: The in vitro results showed that silicate ions could inhibit the cell size of cardiomyocytes, reduce cardiac hypertrophic gene expression, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and b-myosin heavy chain (b-MHC), decrease the content of intracellular calcium induced by Ang II. In vivo experiments in mice confirmed that intravenous injection of silicate ions could remarkably inhibit the cardiac hypertrophy and promote the formation of capillaries, further alleviating Ang II-induced cardiac function disorder. CONCLUSION: This study demonstrated that the released silicate ions from CS possessed potential value as a novel therapeutic strategy of pathological cardiac hypertrophy, which provided a new insight for clinical trials.

Effect of Laser Power on Hybrid Laser-Gas Metal Arc Welding (GMAW) of a 6061 Aluminum Alloy

Zhou Huiling,Fu Fanglian,Dai Zhixin,Qiao Yanxin,Chen Jian,Yang Lanlan,Liu Wen 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.11

The effect of laser power on the geometrical characteristics, microstructure and micro-hardness of the welding joints for 6061 aluminum alloy after hybrid laser-gas metal arc welding (GMAW) was investigated. The results showed that the welding joints from "Bottom" to "Top" were mainly composed of planar crystals, columnar crystals, and equiaxed dendrites. With increasing laser power, the weld depth and width and the grain size increased. When the laser power reached 5 kW, pores could be found in the weld pool region. Micro-hardness measurements showed that the application of higher laser power hardly changed the hardness of the welding joint.

Molecular cloning and functional characterization of a sweetpotato chloroplast IbDHAR3 gene in response to abiotic stress

Wenbin Wang,Xiangpo Qiu,Ho Soo Kim,Yanxin Yang,Dianyun Hou,Xuan Liang,곽상수 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.1

Dehydroascorbate reductase (DHAR) plays a critical role in the regeneration of ascorbic acid (AsA), and widely involved in plant tolerance to biotic and abiotic stresses. In this study, the IbDHAR3 gene was cloned from sweetpotato cultivar Xushu 18 by RT-PCR. The full-length of this gene was 813 bp which encodes 270 amino acids. The IbDHAR3 protein contained two conserved domains of glutathione S-transferase (GST) and GST-C-DHAR, and one chloroplast transit peptide with 52 amino acids length. Transient expression in tobacco leaf epidermal cells indicated that IbDHAR3 protein is subcellular localized to chloroplast. The qRT-PCR results revealed that the relative expression level of IbDHAR3 in leaves is much higher than that in other tissues, and could be up-regulated by ABA, drought, salinity, and high-temperature stresses. The seed germination rate and root elongation were increased in contrast to wild type under mannitol and NaCl stresses in T3 transgenic Arabidopsis overexpressing IbDHAR3 gene. The soil drought experiments showed that the overexpression of IbDHAR3 gene in Arabidopsis reduced the malondialdehyde (MDA) and the H2O2 content, enhanced the level of AtGR gene expression, superoxide dismutase (SOD), ascorbate peroxidase (APX), DHAR activity, and the AsA content. Therefore, overexpression of IbDHAR3 gene could enhance the ability of scavenging reactive oxygen species such as H2O2 by promoting AsA-glutathione cycle and related antioxidant enzymes system, thereby contributing to increased stress tolerance in Arabidopsis.

Molecular characterization of a sweet potato stress toleranceassociated trehalose-6-phosphate synthase 1 gene (IbTPS1) in response to abiotic stress

Wenbin Wang,Huan Yu,김호수,Yanxin Yang,Xiangpo Qiu,곽상수 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.3

Trehalose-6-phosphate synthase (TPS) plays an important regulatory role in the response of plants to multiple abiotic stresses. However, our knowledge of the stress tolerance functions of TPS genes in sweet potato (Ipomoea batatas [L.] Lam) remains limited. In the present study, we isolated and functionally characterized the sweet potato gene encoding TPS1, IbTPS1. Sequence analysis showed that IbTPS1 belongs to class I TPS proteins and harbors highly conserved acceptor (glucose- 6-phosphate [Glc6P]) and donor (uridine diphosphoglucose [UDP-Glc]) binding sites. The IbTPS1 gene showed the highest level of constitutive expression in leaves and storage roots of sweet potato plants and was induced by several environmental stresses including drought, salt, and heat shock. The IbTPS1 protein might be localized to the cytosol. Complementation assay of yeast tps1Δ and tps1Δtps2Δ growth-defective mutants confirmed the TPS activity of IbTPS1, and truncation of the N-terminal extension of IbTPS1 (ΔNIbTPS1) increased the catalytic activity of the protein. Additionally, expression of IbTPS1 in yeast conferred abiotic stress tolerance to dehydration, salinity, and oxidation, and expression of ΔNIbTPS1 further enhanced the tolerance to abiotic stresses. The results of this study advance our understanding of the functions of IbTPS1 under abiotic stress conditions. Our results suggest that the IbTPS1 gene is an excellent candidate for improving the stress tolerance of different crop plants.