Transient Thermal Response of a Multilayered Geomaterial Subjected to a Heat Source

Lu Jun Wang,Zhi Yong Ai 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.9

The analysis of layered geomaterials thermo-mechanical coupling response is important in design and analysis of a nuclear waste repository. Conventional analytical approaches usually have some intrinsic faults of ill-conditioned matrices for thick layers or accumulative numerical errors for a great quantity of layers for containing positive exponential functions. This paper presents a stable computational approach with no positive exponential functions to study the transient thermal responses of a layered geomaterial subjected to a heat source. Based on the governing equations of thermo-mechanical coupling problems, the analytical layer elements for a finite layer and a half–space are derived by utilizing Laplace and Hankel transforms. The analytical layer elements are then assembled into the total stiffness matrix and solved in the transformed domain. Finally, the Laplace–Hankel transform inversion is employed to obtain an actual solution in the physical domain. Numerical computations indicate that the difference of geomaterial mass properties between layers shows obvious effects on thermal response of the layered system, and these results can be served as a benchmark solution for future analyses of stratified material.

Early Enteral Nutrition and Sepsis-Associated Acute Kidney Injury: A Propensity Score Matched Cohort Study Based on the MIMIC-III Database

Jun Wang,Li Jiang,Sheng Ding,Si-Yi He,Shun-Bi Liu,Zhong-Jie Lu,Yuan-Zhang Liu,Li-Wen Hou,Bin-Su Wang,Jin-Bao Zhang 연세대학교의과대학 2023 Yonsei medical journal Vol.64 No.4

Purpose: We aimed to analyze the optimal timing of enteral nutrition (EN) in the treatment of sepsis and its effect on sepsis-asso ciated acute kidney injury (SA-AKI.)Materials and Methods: The MIMIC-III database was employed to identify patients with sepsis who had received EN. With AKI as the primary outcome variable, receiver operating characteristic (ROC) curves were utilized to calculate the optimal cut-off time of early EN (EEN). Propensity score matching (PSM) was employed to control confounding effects. Logistic regressions and propen sity score-based inverse probability of treatment weighting were utilized to assess the robustness of our findings. Comparisons within the EEN group were performed. Results: 2364 patients were included in our study. With 53 hours after intensive care units (ICU) admission as the cut-off time of EEN according to the ROC curve, 1212 patients were assigned to the EEN group and the other 1152 to the delayed EN group. The risk of SA-AKI was reduced in the EEN group (odds ratio 0.319, 95% confidence interval 0.245–0.413, p<0.001). The EEN patients re ceived fewer volumes (mL) of intravenous fluid (IVF) during their ICU stay (3750 mL vs. 5513.23 mL, p<0.001). The mediating ef fect of IVF was significant (p<0.001 for the average causal mediation effect). No significant differences were found within the EEN group (0–48 hours vs. 48–53 hours), except that patients initiating EN within 48 hours spent fewer days in ICU and hospital. Conclusion: EEN is associated with decreased risk of SA-AKI, and this beneficial effect may be proportionally mediated by IVF volume.

Estimation of main cable tension force of suspension bridges based on ambient vibration frequency measurements

Jun Wang,Weiqing Liu,Lu Wang,Xiaojian Han 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.56 No.6

In this paper, a new approach based on the continuum model is proposed to estimate the main cable tension force of suspension bridges from measured natural frequencies. This approach considered the vertical vibration of a main cable hinged at both towers and supported by an elastic girder and hangers along its entire length. The equation reflected the relationship between vibration frequency and horizontal tension force of a main cable was derived. To avoid to generate the additional cable tension force by sagextensibility, the analytical solution of characteristic equation for anti-symmetrical vibration mode of the main cable was calculated. Then, the estimation of main cable tension force was carried out by antisymmetric characteristic frequency vector. The errors of estimation due to characteristic frequency deviations were investigated through numerical analysis of the main cable of Taizhou Bridge. A field experiment was conducted to verify the proposed approach. Through measuring and analyzing the responses of a main cable of Taizhou Bridge under ambient excitation, the horizontal tension force of the main cable was identified from the first three odd frequencies. It is shown that the estimated results agree well with the designed values. The proposed approach can be used to conduct the long-term health monitoring of suspension bridges.

Accumulation of Flavonoids and Antioxidant Activity of Stellera chamaejasme by an Efficient Callus Culture

Jun-li Wang,Xuan Xiao,Qian Wang,Xiaoxu Li,Lu Zhang,Jianfei Li 한국원예학회 2013 Horticulture, Environment, and Biotechnology Vol.54 No.5

An efficient callus proliferation system of Stellera chamaejasme was developed. The calli were initially induced by cultivating the leaf explants on the MS medium containing 1.0 mg·L-1 2,4-dichlorophenoxy acetic acid (2,4-D). The culture had its fresh and dry weights increased by about 29 and 25 times, respectively, through further cultivation on the MS medium containing 0.5 mg·L-1 α-naphthalene acetic acid (NAA) and 1.0 mg·L-1 n-phenyl-n′-1,2,3-thiadiazol-5-ylurea (TDZ). The concentrations of NAA and 6-benzylaminopurine (BA) for an efficient accumulation of the total flavonoids in the callus were found to be 1.0 mg·L-1 and 0.25 mg·L-1, respectively. With this combination,the content of the total flavonoids slightly increased to 10.8 mg·g-1 dry weight (DW) in comparison to 10.1 mg·g-1DW obtained in the root of wild-type plant. The antioxidant activities of all flavonoid extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The flavonoid extracts from the callus as induced by 1.0 mg·L-1 NAA and 0.25 or 0.5 mg·L-1 BA was very active in radical scavenging, and their IC50 values were 11.94 and 19.17 μg·mL-1,respectively. Compared to the ascorbic acid (IC50 21.21 μg·mL-1), the antioxidant activity of callus from S. chamaejasme was even stronger, suggesting that be another potential source of new natural antioxidants.

Down-regulated MYH11 Expression Correlates with Poor Prognosis in Stage II and III Colorectal Cancer

Wang, Ren-Jie,Wu, Peng,Cai, Guo-Xiang,Wang, Zhi-Min,Xu, Ye,Peng, Jun-Jie,Sheng, Wei-Qi,Lu, Hong-Fen,Cai, San-Jun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.17

The MYH11 gene may be related to cell migration and adhesion, intracellular transport, and signal transduction. However, its relationship with prognosis is still uncertain. The aim of this study was to investigate correlations between MYH11 gene expression and prognosis in 58 patients with stage II and III colorectal cancer. Quantitative real-time polymerase chain reaction was performed in fresh CRC tissues to examine mRNA expression, and immunohistochemistry was performed with paraffin-embedded specimens for protein expression. On univariate analysis, MYH11 expression at both mRNA and protein levels, perineural invasion and lymphovascular invasion were related to disease-free survival (p<0.05; log-rank test). Cancers with lower MYH11 expression were more likely to have a poor prognosis. Otherwise, MYH11 expression was unrelated to patient clinicopathological features. On multivariate analysis, low MYH11 expression proved to be an independent adverse prognosticator (p<0.05). These findings show that MYH11 can contribute to predicting prognosis in stage II and III colorectal cancers.

Stabilization of a Coupled ODE-wave System with Disturbances

Lu Lu,Yu-Long Zhang,Jun-Min Wang,Dong-Xia Zhao 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.3

This paper is devoted to stabilizing an ODE-PDE coupled system with boundary disturbance, where the PDE is chosen to be a wave equation with viscous damping. Applying the active disturbance rejection control (ADRC) technic, the unknown disturbance is estimated by the extended state observer (ESO). Assuming the absence of disturbance, the dynamic boundary connection is designed. The methods of spectral analysis and separation of operator are applied, which ensures the Riesz basis property as well as the spectrum determined growth condition. The exponential stability of the coupled system without disturbance is then concluded. Finally, combining the disturbance estimation and the dynamic boundary connection, a feedback controller designed to stabilize the coupled system, and the closed-loop system is proved to be asymptotically stable.

Genome-wide identification and characterization of the Dof gene family in moso bamboo (Phyllostachys heterocycla var. pubescens)

Tao Wang,Jin-Jun Yue,Xue-Ji Wang,Lu Xu,Lu-Bin Li,Xiao-Ping Gu 한국유전학회 2016 Genes & Genomics Vol.38 No.8

The Dof (DNA binding with One Finger) family of single zinc finger proteins is a family of plant-specific transcription factors. These transcription factors have a variety of important functions in different biological processes in plants. In the current study, we identified 26 Dof family genes in moso bamboo (Phyllostachys heterocycla var. pubescens). A complete overview of PhDof genes in moso bamboo is presented, including the gene structures, phylogeny, protein motifs and expression patterns. Phylogenetic analysis of the 26 PhDof proteins identified four classes constituting seven clusters (A, B1, C1, C2, D1, D2 and D3). In addition, a comparative analysis between the Dof genes in moso bamboo, Arabidopsis (Arabidopsis thaliana L.) and rice (Oryza sativa L.) was also performed, and several putative paralogous and orthologous genes were identified. The exon numbers in Dof genes ranged from one to three in many plants; however, the exon number in PhDofs ranged from one to four. The PhDof genes displayed differential expression in different parts of the shoot and at different flower development stages. This study represents the first step towards a genome-wide analysis of the Dof genes in moso bamboo. Our study provides a useful reference for cloning and functional analysis of members of the Dof gene family in moso bamboo and other species.

Profile of disposition, tissue distribution and excretion of the novel anti-human immunodeficiency virus (HIV) agent W-1 in rats

Ying-Yuan Lu,Xiao-Wei Wang,Xin Wang,Wen-Bing Dai,Qiang Zhang,Pu Li,Ya-Qing Lou,Chuang Lu,Jun-Yi Liu,Guo-Liang Zhang 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

The purpose of this study was to characterize the disposition, distribution, excretion and plasma protein binding of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W- 1) in rats. Concentrations of W-1 within biological samples were determined using a validated high performance liquid chromatography method. The plasma protein binding of W-1 was examined by equilibrium dialysis method. After oral administration of W-1 (50, 100 and 200 mg/kg, respectively) in self-microemulsifying drug delivery system formulation, the pharmacokinetic parameters of W-1 were as follows: the peak plasma concentrations (Cmax) were 0.42, 1.50 and 2.55 μg/mL, the area under the curve (AUC0-t) were 0.89, 2.27 and 3.96 lg/h mL and the plasma half-life (t1/2) were 5.15, 3.77 and 3.77 h, respectively. Moreover, the prototype of W-1 was rapidly and extensively distributed into fifteen tissues, especially higher concentrations were detected in intestine, stomach and liver, respectively. The plasma protein binding of W-1 in rat, beagle dog and human were in the range of 97.96–99.13 %. This study suggested that W-1 has an appropriate pharmacokinetics in rats, such as rapid absorption, moderate clearance, and rapid distribution to multiple tissues. Those properties provide important information for further development W-1 as an anti-HIV-1 drug candidate.

Study on Nano-Metal Oxide and Carbon Nanotube Composites on Thermal Decomposition of Potassium Perchlorate

Ping-An Liu,Meng-Jun Wang,Lu Wang,Jun Wang,Ting Wang 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.4

In this study, novel carbon nanotube (CNT) and transition-metal oxides (TMOs) nanoparticle catalysts were prepared and their effects on the thermal decomposition of potassium perchlorate (KP) were investigated. Nanocatalysts have been widely studied because of their excellent properties, such as the high surface energies of nanoparticles and their ease of agglomeration adversely affect their catalytic performances. Good dispersion is the key to good nanocatalytic activity. The composite catalysts were prepared by loading a nanocatalyst on CNTs; this improves nanoparticle dispersion, promotes electron transfer during the reaction, and increases the catalytic effect. Different types of CNT-based composite catalysts and their corresponding single nanocatalysts were each added to KP. The effects of the catalysts on the thermal decomposition of KP were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The activity of each catalyst was evaluated on the basis of the changes in the thermal decomposition peaks and the apparent decomposition heats. The results show that the activity of a composite catalyst in KP thermal decomposition is much higher than that of its corresponding single nanocatalyst.

Sustainable Development in Hong Kong : a Review of Policy, Practices in Building Design and Construction

Stephen Siu Yu Lau, Jun Salie Wang, Lam Leslie Lu The University of Seoul 2003 International journal of urban sciences (IJUS) Vol. No.

Population wise, Hong Kong has too many people on too small a physical entity - 1,075 square kilometers divided by as many as 240 no. Islands. Natural resources-wise, Hong Kong has too little to offer, as almost all its agricultural lands have been converted into building land, leaving no alternative but to import drinking water and daily supplies from across the Hong Kong-Mainland border on a daily basis. Insatiable demands for housing due to an ever-increasing population growth left the government with little options but to embark on an unprecedented urban form of hyper-density. In 1997, the Hong Kong government commissioned a study known as Sustainable Development for the 21st Century in Hong Kong (SUSDEV 21). The Study jump-started the city`s participation in a worldwide endeavor to embrace sustainable development. The three years expedition guided the city through a world tour and studies on sustainable development from an international frontier, regional frontier, to a local frontier, and ended with a definition of sustainable development for Hong Kong, as well as a policy-making mechanism to achieve sustainability. Institutional efforts to promote sustainability has been complimented by efforts from professionals in the construction and building sector in an equally thorough and holistic manner, which include law-enforcers, developers, architects and builders. This paper presents a critical review and insight into recent works by each of the players mentioned in the text.