Photodetachment of H^− near two perpendicular metal surfaces

De-Hua Wang 한국물리학회 2011 Current Applied Physics Vol.11 No.5

It is a well-known fact that the surfaces can affect the photodetachment of negative ion. In this paper, we focus on how the photodetachment cross-section of H^− is altered when it is placed near two perpendicular metal surfaces. We begin by briefly presenting the electrostatic image potential of the detached electron caused by the metal surfaces, then we study the classical motion of the photo-detached electron near two perpendicular metal surfaces. The photodetachment cross-section of this system has been derived and calculated based on the closed orbit theory. The results show that the cross-section depends on the photon energy and the ion-surface distances sensitively. Compared to the case of the photodetachment of H^− near one metal surface, the oscillatory structure in the cross-section of our system becomes much more complicated. This study provides a new understanding on the photodetachment process of negative ion or atoms in the vicinity of surfaces or cavities.

RTN4 3'-UTR Insertion/Deletion Polymorphism and Susceptibility to Non-Small Cell Lung Cancer in Chinese Han Population

Lu, De-Yi,Mao, Xu-Hua,Zhou, Ying-Hui,Yan, Xiao-Long,Wang, Wei-Ping,Zheng, Ya-Biao,Xiao, Juan-Juan,Zhang, Ping,Wang, Jian-Guo,Ashwani, Neetika,Ding, Wei-Liang,Jiang, Hua,Shang, Yan,Wang, Ming-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Nogo protein, encoded by gene reticulon-4 (RTN4), includes three major isoforms by different splicing, named Nogo-A Nogo-B and Nogo-C. Nogo proteins play an important role in the apoptosis of cells, especially in tumor cells. RTN4 single nucleotide polymorphisms (SNPs) can influence the efficiency of transcription and translation thus being related with an individual's predisposition to cancer. The CAA insertion/deletion polymorphism (rs34917480) within RTN4 3'-UTR has been reported to be associated with many cancer types. In order to investigate the relationship between this polymorphism and susceptibility to non-small cell lung cancer (NSCLC) in the Chinese population, we conducted the present case-control study including 411 NSCLC patients and 471 unrelated healthy controls. The genotype distributions were significantly different between cases and controls (p=0.014). We found that the del allele could significantly increase NSCLC risk (ins/ins vs ins/del: p=0.007, OR 1.46, 95%CI=1.11-1.93; dominant model: p=0.004, OR 1.47, 95%CI=1.13-1.92 and allele model: p=0.008, OR 1.35, 95%CI=1.08-1.67). This association was stronger in participants over 60 years old, males and smokers. We therefore conclude that the CAA insertion/deletion polymorphism (rs34917480) contributes to non-small cell lung cancer risk in Chinese population. Age, sex and environmental exposure are also related to carcinogenic effects of rs34917480.

A novel charring agent containing caged bicyclic phosphate and its application in intumescent flame retardant polypropylene systems

Hua-Qiao Peng,Qian Zhou,De-Yi Wang,Li Chen,Yu-Zhong Wang 한국공업화학회 2008 Journal of Industrial and Engineering Chemistry Vol.14 No.5

A novel charring agent, bis(2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxo-4-hydroxymethyl) phenylphosphonate (BCPPO), was synthesized and characterized by FT-IR, 1H NMR and 31P NMR spectroscopies. Moreover, the novel charring agent combining with ammonium polyphosphate (APP) as well as melamine (MA) was adopted as intumescent flame retardants (IFR) to impart flame retardance and dripping resistance to polypropylene (PP). Flammability and thermal behaviors of the treated PP were investigated by Limiting Oxygen Index (LOI), Vertical Burning Test (UL-94), Thermogravimetric Analysis (TGA) and Cone Calorimeter test. Results indicate that the intumescent flame retardant with the novel charring agent shows both excellent flame retardance and anti-dripping abilities for PP when the three main components of IFR coexist at appropriate proportions, and the optimum flame retardant formulation is APP:MA:BCPPO = 3:1:1 that gives an LOI of 30.3 and UL- 94 V-0 rating, moreover, both the heat release rate (HRR) and the total heat release (THR) of IFR-PP with the optimum formulation decrease significantly relative to PP from cone calorimeter analysis. The residues from decomposition of the IFR-treated PP was characterized by FT-IR spectroscopy and SEM micrograph, and it was found that the char yield as well as char properties have direct effects on the flame retardance and anti-dripping behaviors of the treated PP.

Integrin-linked Kinase Functions as a Tumor Promoter in Bladder Transitional Cell Carcinoma

Wang, De-Lin,Lan, Jian-Hua,Chen, Liang,Huang, Biao,Li, Zeng,Zhao, Xiu-Min,Ma, Qiang,Sheng, Xia,Li, Wen-Bin,Tang, Wei-Xue Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

The aim of this study was to elucidate the role of the integrin-linked kinase (ILK) gene in development of human bladder transitional cell carcinoma (BTCC). Expression of ILK protein and ILK mRNA in 56 cases of human BTCC tissue and in 30 cases of adjacent normal bladder tissue was detected by immunohistochemistry S-P and reverse transcription polymerase chain reaction (RT-PCR), respectively. Four specific miRNA RNAi vectors targeting human ILK were synthesized and transfected into BIU-87 cells by liposome to obtain stable expression cell strains. The influence of ILK on proliferation of BTCC was detected by MTT, FCM on athymic mouse tumorigenesis. The positive rate of ILK protein in BTCC tissue (53.6%) was much higher than adjacent normal bladder tissue (10.0%) (p<0.05). Similarly, expression of ILK mRNA in BTCC tissue ($0.540{\pm}0.083$) was significantly higher than in adjacent normal bladder tissue ($0.492{\pm}0.070$) (p<0.05). MTT showed that the proliferation ability of miRNA-ILK transfected group was clearly decreased (p<0.05), the cell cycle being arrested in G0/G1-S, an tumorigenesis in vivo was also significantly reduced (p<0.05). ILK gene transcription and protein expression may be involved in the development of BTCC, so that ILK might be the new marker for early diagnosis and the new target for gene treatment.

Experience of Congenital Choledochal Cyst in Adults:Treatment, Surgical Procedures and Clinical Outcome in the Second Affiliated Hospital of Harbin Medical University

De Quan Wu,Qiu Shi Wang,Hong Bo Jia,Hong Shang,Xiang Yu Zhong,Wen Xue Zhou,Zhen Hua Sun,Long Xian Zheng 대한의학회 2004 Journal of Korean medical science Vol.19 No.6

NANOTOXICITY OF MULTIWALL CARBON NANOTUBES TO A549 CELLS IN VITRO

FU-DE WANG,Ying Tang,Yong Ji Yang,CHAN JIN,HUA ZHANG,HAO LIANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

Multiwall carbon nanotubes (MWCNTs) have been widely applied in many ¯elds due to theexcellent physical and chemical properties. As the production and applications of nanotubesexpand, public concern about their potential risks to human health has also raised. Cytotoxicityof MWCNTs was evaluated in this study using a cultured human epithelial cell line A549. Uptakeof MWCNTs by cultured A549 cells was observed by TEM imaging. Dose-dependent decrease ofcell viability showed the cytotoxicity of MWCNTs. Signi¯cant reactive oxygen species (ROS)generation and GSH depletion which reduced the cellular antioxidant level could be the majorfactor of cytotoxicity induced by MWCNTs. MWCNTs seemed to trigger the activation of cellautophagy with the intracellular ATG16L1 level increase as a defense mechanism.

Identification of Specific Gene Modules in Mouse Lung Tissue Exposed to Cigarette Smoke

Xing, Yong-Hua,Zhang, Jun-Ling,Lu, Lu,Li, De-Guan,Wang, Yue-Ying,Huang, Song,Li, Cheng-Cheng,Zhang, Zhu-Bo,Li, Jian-Guo,Xu, Guo-Shun,Meng, Ai-Min Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Background: Exposure to cigarette may affect human health and increase risk of a wide range of diseases including pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, lung fibrosis and lung cancer. However, the molecular mechanisms of pathogenesis induced by cigarettes still remain obscure even with extensive studies. With systemic view, we attempted to identify the specific gene modules that might relate to injury caused by cigarette smoke and identify hub genes for potential therapeutic targets or biomarkers from specific gene modules. Materials and Methods: The dataset GSE18344 was downloaded from the Gene Expression Omnibus (GEO) and divided into mouse cigarette smoke exposure and control groups. Subsequently, weighted gene co-expression network analysis (WGCNA) was used to construct a gene co-expression network for each group and detected specific gene modules of cigarette smoke exposure by comparison. Results: A total of ten specific gene modules were identified only in the cigarette smoke exposure group but not in the control group. Seven hub genes were identified as well, including Fip1l1, Anp32a, Acsl4, Evl, Sdc1, Arap3 and Cd52. Conclusions: Specific gene modules may provide better understanding of molecular mechanisms, and hub genes are potential candidates of therapeutic targets that may possible improve development of novel treatment approaches.

Clerodane furanoditerpenoids from the stems of Tinospora sinensis

Jun-Sheng Zhang,De-Feng Xu,Yin-Yin Wang,Ren-Fen Ma,Hua Zhang 대한약학회 2022 Archives of Pharmacal Research Vol.45 No.5

One new clerodane-type furanoditerpenoidtinosinoid A ( 1 ) and nine new nor-clerodane analogs tinosinoids B–J ( 2 − 10 ) have been isolated from the stems ofTinospora sinensis . The structures of the new compoundswith absolute confi gurations have been elucidated by spectroscopicmeans, including MS, NMR and ECD techniques,as well as chemical correlation. Compound 1 is a rare sulfurcontainingclerodane diterpenoid incorporating a 2-mercaptoethanolunit via a thioether bond, while compounds 4 / 5and 9 represent two pairs of unusual equilibrium regioisomersthrough an interesting intramolecular transesterifi cation. Our bioassays established that 1 and 8 displayed moderateantiproliferative eff ects against two human tumor celllines, and 9 and 10 showed signifi cant α -glucosidase inhibitoryactivities. A kinetics study revealed that compound 10was a noncompetitive α -glucosidase inhibitor, and its possiblebinding mode to the enzyme was further probed bymolecular docking experiments.

Effects of boundary layer and liquid viscosity and compressible air on sloshing characteristics

Chang-Fang Zou,De-Yu Wang,Zhong-Hua Cai 대한조선학회 2015 International Journal of Naval Architecture and Oc Vol.7 No.4

In this paper, numerical investigations for tank sloshing, based on commercial CFD package FLUENT, are performed to study effects of boundary layer grid, liquid viscosity and compressible air on sloshing pressure, wave height and rising time of impact pressure. Also, sloshing experiments for liquids of different viscosity are carried out to validate the numerical results. Through comparison of numerical and experimental results, a computational model including boundary layer grid can predict the sloshing pressure more accurately. Energy dissipation due to viscous friction leads to reduction of sloshing pressure and wave elevation. Sloshing pressure is also reduced because of cushion effect of compressible air. Due to high viscosity damping effect and compressible air effect, the rising time of impact pressure becomes longer. It is also found that liquid viscosity and compressible air influence distribution of dynamic pressure along the vertical tank wall.

Dynamic and Damage Characteristics of Mortar Composite under Impact Load

Qing Li,Tong-de Zhao,Chen Huang,Bing-bing Yu,Zheng-Hua Gao,Kai Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.3

In the process of underground construction, it is common to spray concrete on the working surface, which will form a concrete-rock composite structure, to achieve the expected reinforcement effect. Compared with pure concrete or rock structures, composite structures have different mechanical properties, energy evolution and damage characteristics. Understanding the dynamic mechanics and damage characteristics of composite structures under impact loads is important to the safety of underground engineering construction. First, dynamic compression tests on different grades of mortar-sandstone composite specimens were carried out by using a Hopkinson pressure bar system to discuss the effect of impact velocities on the mechanical properties and failure modes of composite specimens. The results show that the dynamic peak stress, strain energy density and fragmentation block of the mortar-sandstone composite have an obvious strain rate effect. With an increase in impact velocity, the internal cracks of the sample do not have sufficient time to expand, and the energy absorbed by the sample leads to the continuous initiation of new cracks in the sample, resulting in an increasing damage degree of composite specimens. The increase in mortar strength can significantly increase the peak stress, improve the load-bearing capacity of the sample, and reduce the degree of sample damage. At the same impact velocity, the fragmentation degree of the mortar sample is more severe than that of sandstone, and the mortar sample is broken into powder debris, while the sandstone is broken into fragments. In addition, according to the failure properties of the composite sample, the mortar and sandstone samples are described by different damage models, and the dynamic damage constitutive model of the mortar-sandstone composite is established based on the overlay principle. The dynamic test results were fitted. The research shows that the fitting curves of the model are well fitted with the test curves and that the model accurately reflects the changes in the mechanical parameters of the composite specimens.