THE INVESTIGATION OF ATOMIC STRUCTURE AND ELECTRIC PROPERTY OF POLYCRYSTALLINE CdS(Se) FILMS

Zheng, Zheng, Yufeng,Ma, Ma, Zhongquan,Deng, Deng, Rengping,Zha, Zha, Chaozheng 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.1 No.1

The spray-sintering process and thermal evaporation technique were appliced to fabrication of polycrystalline CdS(Se) films on glass substrate respectively. Their atomic structure and surface morphology were analyzed by XRD and SEM spectrometers. It was found that films made in spraysintering process were of the zince-blende structure but the films evaporated in vacuum showed a two-dimensional layer structure of atom stacked along c axis with a lattice parameter of $3.351{\AA}$. A variation of the conductivity with annealing temperature in air and nitrogen for sintered films with impurities has been ascribed to the mobility and the concentration of majority carrier. A increase of the electric conductance with temperature in any ambience for evaporated films was resulted from forming a conductive layer which promoted the mobilization of eletron or hole. The absorption and desorption of oxygen in subsequent annealing process has alos been discussed.

Optimization of Medium Components for Plasmid Production by Recombinant E. coli $DH5{\alpha}$ $pUK21CMV{\beta}1.2$

Zheng, Shuzhen,Friehs, Karl,He, Ning,Deng, Xu,Li, Qingbiao,He, Zheng,Xu, Chenyun,Lu, Yinghua Korean Society for Biotechnology and Bioengineerin 2007 Biotechnology and Bioprocess Engineering Vol.12 No.3

In this study we investigated the effects of carbon and nitrogen sources, and the carbon to nitrogen ratio (C:N) of growth medium on the production of plasmid DNA by $pUK21CMV{\beta}1.2$ harbouring recombinant E. coli. The results indicated that sucrose and casein peptone were the most suitable carbon and nitrogen sources, respectively, for plasmid production, and the plasmid concentration was significantly influenced by the C:N ratio. A Box-Behnken design and surface response methodology were employed to formulate the optimal medium. In the optimized medium, a plasmid concentration of 51.80mg/L and a plasmid selectivity of 23.49mg/g were achieved after 24h of incubation. These values were approximately 3.5 and 1.7 times higher, respectively, than those obtained on the original LB medium.

Pulmonary IFN-γ Causes Lymphocytic Inflammation and Cough Hypersensitivity by Increasing the Number of IFN-γ-Secreting T Lymphocytes

Deng Zheng,Ding Wenbin,Li Fengying,Shen Shuirong,Huang Chuqin,Lai Kefang 대한천식알레르기학회 2022 Allergy, Asthma & Immunology Research Vol.14 No.6

Purpose: Respiratory viral infection increases the number of lung-resident T lymphocytes, which enhance cough sensitivity by producing interferon-γ (IFN-γ). It is poorly understood why IFN-γ-secreting T lymphocytes persist for a long time when the respiratory viruses have been removed. Methods: Repeated pulmonary administration of IFN-γ and intraperitoneal injection with different inhibitors were used to study the effects of pulmonary IFN-γ in mice and guinea pigs. Results: IFN-γ administration caused the increasing of IFN-γ-secreting T lymphocytes in both lung and blood, followed by the elevated physiological level of IFN-γ in the lung, the airway inflammation and the airway epithelial damage. IFN-γ administration also enhanced the cough sensitivity of guinea pigs. IFN-γ activated the STAT1 and extracellular signal-regulated kinase (ERK) pathways in lung tissues, released IFN-γ-inducible protein 10 (IP-10), and resulted in F-actin accumulation in lung-resident lymphocytes. The CXC chemokine receptor 3 (CXCR3) inhibitor potently suppressed all the IFN-γ-induced inflammatory changes. The STAT1 inhibitor mitigated IFN-γ-secreting T lymphocytes infiltration by inhibiting T lymphocytes proliferation. F-actin accumulation and the ERK1/2 pathway contributed to pulmonary IFN-γ-induced augmentation of the airway inflammation and increasing of IFN-γ-secreting T lymphocytes in blood. Conclusions: High physiological levels of IFN-γ in the lung may cause pulmonary lymphocytic inflammation and cough hypersensitivity by increasing the number of IFN-γ-secreting T lymphocytes through the IP-10 and CXCR3 pathways.

Compressive behavior of steel stirrups-confined square Engineered Cementitious Composite (ECC) columns

Zheng, Pan-deng,Guo, Zi-xiong,Hou, Wei,Lin, Guan Techno-Press 2021 Advances in concrete construction Vol.11 No.3

Extensive research has been conducted on the basic mechanical property and structural applications of engineered cementitious composites (ECC). Despite the high tensile ductility and high toughness of ECC, transverse steel reinforcement is still necessary to confine ECC for high performance. However, limited research has examined performance of ECC confined with practical amount of transverse reinforcement. This paper presents the results of axial compression tests on 14 square ECC columns and 4 conventional concrete columns (used as control specimens) with transverse reinforcement. The test variables were spacing, configuration (square ties or square and diamond shape ties), and yield strength of stirrups. The test showed that ECC columns confined with steel stirrup had good compressive ductility, and the stirrup spacing had the greatest effect on the compressive performance. The self-confinement effect of ECC results in a more uniform but slower expansion of the whole column compared with CC ones. The test results are then compared against the predictions from a number of existing models for conventional confined concrete. It is indicated that these models fail to predict the axial strains at peak axial stress and the trend of the stress-strain curve of steel stirrups-confined ECC with sufficient accuracy. Several new equations are then proposed for the compressive properties of steel-confined ECC based on test results and potential approaches for future studies are proposed.

Research Progress of Antibiotic Pollution and Adsorption Materials in Aquatic environment

Zheng, Kun,Deng, ChengXun,Deng, Xu,Yu, ZhiMin Urban Science Institute 2019 도시과학 Vol.8 No.2

China is the great powers of use and production of antibiotics.The current process of sewage treatment plants can not effectively remove antibiotics in water. Chinese scholars have detected different kinds of antibiotics in major waters of the country, which have potential harm to human body. Among all kinds of antibiotic treatment technologies, adsorption removal technology has the advantages of simple operation, low cost and high removal efficiency. It is a widely concerned antibiotic removal technology. However, at present, few materials have been put into practical application, and more materials with low cost and high efficiency need to be found. Different adsorptive materials have different adsorptivity to different antibiotics. For different antibiotics, different adsorptive materials can be integrated in the future, and the theory can be extended to application.

An Extended Switched-inductor Quasi-Z-source Inverter

Deng, Kai,Mei, Fei,Mei, Jun,Zheng, Jianyong,Fu, Guangxu The Korean Institute of Electrical Engineers 2014 Journal of Electrical Engineering & Technology Vol.9 No.2

In this paper, an extended switched-inductor quasi-Z-source inverter (ESL-qZSI) with high boost voltage inversion ability is presented, which combines the SL-qZSI with the traditional boost converter, as well as improves the switched-inductor cell. Compared with the classic qZSI topologies, the proposed topology reduces the voltage stresses of capacitors, power devices and diodes for the same input and output voltage. Furthermore, the conversion efficiency is improved. The operation principle of the proposed topology is analyzed in details, which is followed by the comparison between the three topologies. In addition, the performance of the proposed topology is verified by simulations and experiments.

A Hierarchical Model Predictive Voltage Control for NPC/H-Bridge Converters with a Reduced Computational Burden

Zheng Gong,Peng Dai,Xiaojie Wu,Fujin Deng,Dong Liu,Zhe Chen 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

In recent years, voltage source multilevel converters are very popular in medium/high-voltage industrial applications, among which the NPC/H-Bridge converter is a popular solution to the medium/high-voltage drive systems. The conventional finite control set model predictive control (FCS-MPC) strategy is not practical for multilevel converters due to their substantial calculation requirements, especially under high number of voltage levels. To solve this problem, a hierarchical model predictive voltage control (HMPVC) strategy with referring to the implementation of g-h coordinate space vector modulation (SVM) is proposed. By the hierarchical structure of different cost functions, load currents can be controlled well and common mode voltage can be maintained at low values. The proposed strategy could be easily expanded to the systems with high number of voltage levels while the amount of required calculation is significantly reduced and the advantages of the conventional FCS-MPC strategy are reserved. In addition, a HMPVC-based field oriented control scheme is applied to a drive system with the NPC/H-Bridge converter. Both steady-state and transient performances are evaluated by simulations and experiments with a down-scaled NPC/H-Bridge converter prototype under various conditions, which validate the proposed HMPVC strategy.

Mortality of Major Cancers in Guangxi, China: Sex, Age and Geographical Differences from 1971 and 2005

Deng, Wei,Long, Long,Li, Ji-Lin,Zheng, Dan,Yu, Jia-Hua,Zhang, Chun-Yan,Li, Ke-Zhi,Liu, Hai-Zhou,Huang, Tian-Ren Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.4

The incidence and mortality rates of liver and nasopharyngeal cancer in Guangxi province of China have always been among the highest in the world, and cancer is one of the major diseases that pose a threat to the health of residents in Guangxi. However, no systematic study has been performed to evaluate the time trends in the structure of cancer-related deaths and cancer mortality. In this study, we reveal sex, age and geography differences of cancers mortality between three death surveys (1971 to 1973, 1990 to 1992, and 2004 to 2005). The results show that the standardized mortality rate of cancer in Guangxi residents has risen from 43.3/100,000 to 84.2/100,000, the share of cancer deaths in all-cause deaths has increased from 13.3% to 20.7%, and cancer has become the second most common cause of death. The five major cancers, liver cancer, lung cancer, gastric cancer, nasopharyngeal cancer and colorectal cancer, account for 60% of all the cancer deaths. Cancers with growing mortality rates over the past 30 years include lung cancer, colorectal cancer, liver cancer and female breast cancer, of which lung cancer is associated with the sharpest rise in mortality, with a more than 600% rise in both men and women. Cancer death in Guangxi residents occurs mainly in the elderly population above 45 years of age, especially in people over the age of 65. The areas with the highest mortality rates for liver cancer and nasopharyngeal cancer, which feature regional high incidences, include Chongzuo and Wuzhou. Therefore, for major cancers such as liver cancer, lung cancer, gastric cancer, nasopharyngeal cancer and female breast cancer in Guangxi, we can select high-risk age groups as the target population for cancer prevention and control efforts in high-prevalence areas in a bid to achieve the ultimate goal of lowering cancer mortality in Guangxi.

Boundary stress resolution and its application to adaptive finite element analysis

Deng, Jianhui,Zheng, Hong,Ge, Xiurun Techno-Press 1998 Structural Engineering and Mechanics, An Int'l Jou Vol.6 No.1

A novel boundary stress resolution method is suggested in this paper, which is based upon the displacements of finite element analysis and of high precision with stress boundary condition strictly satisfied. The method is used to modify the Zienkiewicz-Zhu ($Z^2$) a posteriori error estimator and for the h-version adaptive finite element analysis of crack problems. Successful results are obtained.

Expression of Transcription Factor FOXC2 in Cervical Cancer and Effects of Silencing on Cervical Cancer Cell Proliferation

Zheng, Chun-Hua,Quan, Yuan,Li, Yi-Yang,Deng, Wei-Guo,Shao, Wen-Jing,Fu, Yan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.4

Objective: Forkhead box C2 (FOXC2) is a member of the winged helix/forkhead box (Fox) family of transcription factors. It has been suggested to regulate tumor vasculature, growth, invasion and metastasis, although it has not been studied in cervical cancer. Here, we analyzed FOXC2 expression in cervical tissues corresponding to different stages of cervical cancer development and examined its correlation with clinicopathological characteristics. In addition, we examined the effects of targeting FOXC2 on the biological behavior of human cervical cancer cells. Methods: The expression of FOXC2 in normal human cervix, CIN I-III and cervical cancer was examined by immunohistochemistry and compared among the three groups and between cervical cancers with different pathological subtypes. Endogenous expression of FOXC2 was transiently knocked down in human Hela and SiHa cervical cells by siRNA, and cell viability and migration were examined by scratch and CCK8 assays, respectively. Results: In normal cervical tissue the frequency of positive staining was 25% (10/40 cases), with a staining intensity (PI) of $0.297{\pm}0.520$, in CIN was 65% (26/40cases), with a PI of $3.00{\pm}3.29$, and in cancer was 91.8% (68/74 cases), with a PI of $5.568 {\pm}3.449$. The frequency was 100% in adenocarcinoma (5/5 cases) and 91.3% in SCCs (63/69 cases). The FOXC2 positive expression rate was 88.5% in patients with cervical SCC stage I and 100% in stage II, showing significant differences compared with normal cervix and CIN. With age, pathologic differentiation degree and tumor size, FOXC2 expression showed no significant variation. On transient transfection of Hela and SiHa cells, FOXC2-siRNA inhibition rates were 76.2% and 75.7%; CCK8 results showed reduced proliferation and relative migration (in Hela cells from $64.5{\pm}3.16$ to $49.5{\pm}9.24$ and in SiHa cells from $60.1{\pm}3.05$ to $44.3{\pm}3.98$) (P < 0.05). Conclusion: FOXC2 gene expression increases with malignancy, especially with blood vessel hyperplasia and invasion degree. Targeted silencing was associated with reduced cell proliferation as well as invasion potential.