Static analysis of 2D-FG nonlocal porous tube using gradient strain theory and based on the first and higher-order beam theory

Xiaozhong Zhang,Jian-Feng Li,Yan Cui,Mostafa Habibi,H. Elhosiny Ali,Ibrahim AlBaijan,Tayebeh Mahmoudi 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.3

This article focuses on the study of the buckling behavior of two-dimensional functionally graded (2D-FG) nanosize tubes, including porosity, based on the first shear deformation and higher-order theory of the tube. The nano-scale tube is simulated using the nonlocal gradient strain theory, and the general equations and boundary conditions are derived using Hamilton’s principle for the Zhang-Fu’s tube model (as a higher-order theory) and Timoshenko beam theory. Finally, the derived equations are solved using a numerical method for both simply-supported and clamped boundary conditions. A parametric study is performed to investigate the effects of different parameters, such as axial and radial FG power indices, porosity parameter, and nonlocal gradient strain parameters, on the buckling behavior of the bi-dimensional functionally graded porous tube. Keywords: Nonlocal strain gradient theory; buckling; Zhang-Fu’s tube model; Timoshenko theory; Two-dimensional functionally graded materials; Nanotubes; Higher-order theory.

Comparisons of Curative and Side Effects of Chemoradiotherapy among Xinjiang Han, Uigur and Kazakh Esophageal Carcinoma Patients

Zhang, Li,Ma, Li-Li,Zhang, Jian-Qing,Yang, Mei,Xun, Tu-Er,Li, Ai Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Objective: This study aimed to explore the differences in the curative and side effects of chemoradiotherapy on esophageal cancer (EC) among Xinjiang Han, Uigur and Kazakh patients. Methods: 170 patients with IIA stage-IV of esophageal squamous cell carcinoma were analyzed retrospectively. Based on different nationalities, they were divided into the Han, Uigur and Kazakh groups. The 1-, 2- and 3-year survival rates, incidence of the side effects (including hematological toxicities, radioactive esophagitis and percutaneous reactions) and application of antibiotics and harmonics were compared among the groups. There was no significant difference in the short-term curative effects among the Han, Uigur and Kazakh groups. The 1- 2- and 3-year survival rates of the three groups were 84%, 40%, 26%; 78%, 27%, 18%; and 60%, 21%, 12% ($x^2$=14.497, P<0.05). The incidence rate of hamatological toxicity ${\geq}$Grade 2 in the Kazakh group was significantly lower than that in the Han or Uigur group. Results: The incidence rates of radioactive esophagitis and percutaneous reactions Grade 2 in the Han group were significantly higher than those in the Uigur or Kazakh group. There was no significant difference in the types of applied antibiotics among the groups, but there were significant differences in the days of antibiotic application and proportion of patients receiving harmonics between the Hans and either of other groups. Conclusion: Chemoradiotherapy shows a better effect in the long-term survival rate among Han EC patients compared with Uigur or Kazakh EC patients. Uigur and Kazakh patients show a better tolerance to the side effects of chemoradiotherapy compared with Hans.

Performance investigation of nanoscale thermal cloak by the perforated silicon film

Zhang Jian,Zhang Haochun,Zhang Dong,Sun Wenbo,Li Yiyi 한국물리학회 2022 Current Applied Physics Vol.35 No.-

In recent years, nanoscale thermal cloak, as a representative of nanoscale heat flux regulation devices, has attracted a lot of attention from researchers. However, the existing design methods are relatively complicated and all adopt constant temperature boundaries, the temperature changes constantly in the real environment, which greatly hinders its engineering applications. In this paper, inspired by phonon localization theory, we construct a nanoscale thermal cloak by a perforated silicon membrane and evaluate its cloaking performance and dynamic response. Results show that when the perforated area is fixed, the more the number of holes, the better the cloaking performance. In addition, the nanoscale thermal cloak still exhibits good cloaking performance in the dynamic environment. Finally, the cloaking mechanism is analyzed by calculating the phonon density of states (PDOS) and mode participation rate (MPR), and the reduction of thermal conductivity in the functional region is attributed to phonon localization.

Reference gene selection for transcriptional profiling by RT-qPCR in the 28-spotted larger potato ladybird

Zhang Yu-Xing,Tan Qiao,Shen Chen-Hui,Wu Jian-Jian,Wu Yi-Kuan,Li Wen-Ze,Jin Lin,Li Guo-Qing 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.2

Henosepilachna vigintioctomaculata is one of the most serious defoliates attacking potatoes. However, studies on functional genes have greatly been limited due to the insufficiency of effective and stable endogenous references to normalize RT-qPCR data. In this report, nine housekeeping genes (RPL4, RPL6, RPL13, RPL32, RPS18, ACT, EF1α, GAPDH and α-TUB) involved in different biological processes were selected. Their expression levels under diverse experimental conditions including developmental stages, tissues, temperatures and host plants were determined using RT-qPCR technology. The tested candidate genes were comprehensively ranked based on five alternative stability analysis methods (Ct value, geNorm, NormFinder, BestKeeper and ReFinder). The results revealed that the optimal internal reference genes varied under different experimental conditions. Any gene pair among the five candidates (RPL4, RPL13, RPL32, RPS18 and EF1α) was a suitable reference gene set under different temperatures and on different host plants. A combination of RPL6 and RPL13 was recommended as the best reference gene set across different developmental stages. A pair of RPS18 and EF1α was ranked as the optimal reference gene combination within different tissues. The most suitable reference genes were RPS18 and RPL13 under four different experimental conditions. Our findings not only establish an accurate and reliable normalization of RT-qPCR data, but also lay a solid foundation for further functional gene researches in H. vigintioctomaculata

Grouting effects evaluation of water-rich faults and its engineering application in Qingdao Jiaozhou Bay Subsea Tunnel, China

Zhang, Jian,Li, Shucai,Li, Liping,Zhang, Qianqing,Xu, Zhenhao,Wu, Jing,He, Peng Techno-Press 2017 Geomechanics & engineering Vol.12 No.1

In order to evaluate the grouting effects of water-rich fault in tunnels systematically, a feasible and scientific method is introduced based on the extension theory. First, eight main influencing factors are chosen as evaluation indexes by analyzing the changes of permeability, mechanical properties and deformation of surrounding rocks. The model of evaluating grouting effects based on the extension theory is established following this. According to four quality grades of grouting effects, normalization of evaluation indexes is carried out, aiming to meet the requirement of extension theory on data format. The index weight is allocated by adopting the entropy method. Finally, the model is applied to the grouting effects evaluation in water-rich fault F4-4 of Qingdao Jiaozhou Bay Subsea Tunnel, China. The evaluation results are in good agreement with the test results on the site, which shows that the evaluation model is feasible in this field, providing a powerful tool for systematically evaluating the grouting effects of water-rich fault in tunnels.

Overexpression of NDRG2 Can Inhibit Neuroblastoma Cell Proliferation through Negative Regulation by CYR61

Zhang, Zhi-Guo,Li, Gang,Feng, Da-Yun,Zhang, Jian,Zhang, Jing,Qin, Huai-Zhou,Ma, Lian-Ting,Gao, Guo-Dong,Wu, Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Several recent studies have showed that the n-myc downstream regulated gene 2 (NDRG2) is a new tumor suppressor gene, and that it plays an important role in tumor suppression in several cancers or cancer cell lines. However, few studies focused on its function in neuroblastoma cells. In the present investigation, we demonstrated that NDRG2 overexpression inhibited their proliferation. Using a cDNA microarray, we found that overexpression of NDRG2 inhibited the expression of cysteine-rich protein 61 (CYR61), a proliferation related gene. From our research, CYR61 may partially hinder NDRG2-mediated inhibition of cell proliferation. Overexpression of NDRG2 resulted in accumulation of cells in the G1 phase, which was accompanied by upregulation of p21 and p27 and downregulation of CDK4 and cyclin D1. Taken together, these data indicate that NDRG2 inhibits the proliferation of neuroblastoma cells partially through suppression of CYR61. Our findings offer novel insights into the physiological roles of NDRG2 in neuroblastoma cell proliferation, and NDRG2 may prove to be effective candidate for the treatment of children with neuroblastoma.

Effects of Differential Distribution of Microvessel Density, Possibly Regulated by miR-374a, on Breast Cancer Prognosis

Li, Jian-Yi,Zhang, Yang,Zhang, Wen-Hai,Jia, Shi,Kang, Ye,Tian, Rui Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Background: The discovery that microRNAs (miRNAs) regulate proliferation, invasion and metastasis provides a principal molecular basis of tumor heterogeneity. Microvessel distribution is an important characteristic of solid tumors, with significant hypoxia occurring in the center of tumors with low blood flow. The distribution of miR-374a in breast tumors was examined as a factor likely to be important in breast cancer progression. Methods: Breast tissue samples from 40 patients with breast cancer were classified into two groups: a highly invasive and metastatic group (HIMG) and a low-invasive and metastatic Group (LIMG). Samples were collected from the center and edge of each tumor. In each group, six specimens were examined by microRNA array, and the remaining 14 specimens were used for real-time RT-qPCR, Western blot and immunohistochemical analyses. Correlation analysis was performed for the miRNAs and target proteins. Follow-up was carried out during 28 months to 68 months after surgery, and survival data were analyzed. Results: In the LIMG, the relative content of miR-374a was lower in the center of the tumor than at its edge; in the HIMG, it was lower at the edge of the tumor, and miR-374a levels were lower in breast cancer tissues than in normal tissues. There was no difference between VEGF-A and VCAM-1 mRNA levels at the edge and center of the tumor; however, we observed a significant difference between VEGF-A and VCAM-1 protein expression levels in these two regions. There was a negative correlation between miR-374a and target protein levels. The microvessel density (MVD) was lower in the center of the tumor than at its edge in HIMG, but the LIMG vessels were uniformly distributed. There was a significant positive correlation between MVD and the number of lymph node metastases (Pearson correlation, r=0.912, P<0.01). The median follow-up time was 48.5 months. LIMG had higher rate of disease-free survival (100%, P=0.013) and longer median survival time (66 months) than HIMG, which had a lower rate of 75% and shorter median survival time (54 months). Conclusions: Our data demonstrated miR-374a to be differentially distributed in breast cancer; VEGF-A and VCAM-1 mRNA had coincident distribution, and the distribution of teh respective proteins was uneven and opposite to that for the miR-374a. These data might explain the differences in the distribution of MVD in breast cancer and variation in breast cancer prognosis.

Diversity and Distribution of Methanogenic Archaea in an Anaerobic Baffled Reactor (ABR) Treating Sugar Refinery Wastewater

( Jian Zheng Li ),( Li Guo Zhang ),( Qiao Ying Ban ),( Ajay Kumar Jha ),( Yi Ping Xu ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.2

The diversity and distribution of methanogenic archaea in a four-compartment anaerobic baffled reactor (ABR) treating sugar refinery wastewater were investigated by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). At an organic loading rate of 5.33 kg COD/m3·day, the ABR could perform steadily with the mean chemical oxygen demand (COD) removal of 94.8% and the specific CH4 yield of 0.21 l/g CODremoved. The CH4 content in the biogas was increased along the compartments, whereas the percentage of H2 was decreased, indicating the distribution characteristics of the methanogens occurred longitudinally down the ABR. A high phylogenetic and ecological diversity of methanogens was found in the ABR, and all the detected methanogens were classified into six groups, including Methanomicrobiales, Methanosarcinales, Methanobacteriales, Crenarchaeota, Arc I, and Unidentified. Among the methanogenic population, the acid-tolerant hydrogenotrophic methanogens including Methanoregula and Methanosphaerula dominated the first two compartments. In the last two compartments, the dominant methanogenic population was Methanosaeta, which was the major acetate oxidizer under methanogenic conditions and could promote the formation of granular sludge. The distribution of the hydrogenotrophic (acid-tolerant) and acetotrophic methanogens in sequence along the compartments allowed the ABR to perform more efficiently and steadily.

Proteomic Analysis of the Aging-related Proteins in Human Normal Colon Epithelial Tissue

Li, Ming,Xiao, Zhi-Qiang,Chen, Zhu-Chu,Li, Jian-Ling,Li, Cui,Zhang, Peng-Fei,Li, Mao-Yu Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.1

In order to screen the aging related proteins in human normal colon epithelia, the comparative proteomics analysis was applied to get the two-dimensional electrophoresis (2-DE) profiles with high resolution and reproducibility from normal colon epithelial tissues of young and aged people. Differential proteins between the colon epithelia of two age groups were found with PDQuest software. The thirty five differential protein-spots were identified by peptide mass fingerprint (PMF) based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and database searching. Among them there are sixteen proteins which are significantly up-regulated in the colonic mucosal epithelia of young people group, which include ATP synthase beta chain, electron transfer flavoprotein alpha-subunit, catalase, glutathione peroxidase 1, annexin A2 and heat shock cognate 71 kDa protein, etc.; There are nineteen proteins which are significantly up-regulated in the colonic mucosal epithelia of aged people group, which include far upstream element-binding protein 1, nucleoside diphosphate kinase B, protein disulfide-isomerase precursor and VDAC-2, etc.. The identified differential proteins appear to be involved in metabolism, energy generation, chaperone, antioxidation, signal transduction, protein folding and apoptosis. The data will help to understand the molecular mechanisms of human colon epithelial aging.

Carbon dispersed iron-manganese catalyst for light olefin synthesis from CO hydrogenation

Jianli Zhang,Kegong Fang,Kan Zhang,Wenhuai Li,Yuhan Sun 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.3

High performance iron-manganese catalysts dispersed with carbon to produce light olefins from CO hydrogenation were prepared by sol-gel method using citric acid as precursor. The effects of carbon content on the bulk structure, the water gas shift reaction, the chain propagation ability and the activity and selectivity of the catalysts were investigated. The results showed that the catalysts were gradually reduced during the decomposition of the precursor when calcined under pure N2. The formation of iron-manganese mixed crystallites was favored and stabilized because of the enhanced interaction of iron and manganese with increasing carbon content. During the subsequent CO hydrogenation reaction, all the catalysts showed high activity and olefin selectivity. With increasing carbon content, the water gas shift (WGS) reaction was restrained and the chain propagation ability was inhibited. Catalysts with higher carbon content showed much lighter hydrocarbon products; however, the selectivity of CH4 was almost unchanged.