A simple approach to the elasto-plastic coupling analyses of circular tunnels in confining pressure-dependent strain-softening rock masses

Qiang Zhang,Cheng Li,Qiang Guo,Ming Min,Yanning Wang,Binsong Jiang 한국자원공학회 2017 Geosystem engineering Vol.20 No.5

The conventional strain-softening behaviors which assume the strength parameters as the functions of the plastic strain have been studied using various methods. However, rock-like materials have also been found to manifest pressure-dependent behavior for both elastic and plastic rock masses. The realization of the radial stress was found to be continuous, and gradually increased from supporting stress to in situ stress for the circular openings under hydrostatic pressure. The radial stress was spaced as numbers of sections, and each annulus was considered as an ideal plastic rock mass. The close-formed analytical solutions of each annulus can be easily obtained. Therefore, using the displacement continuum and stress boundary conditions, the dimensionless radius corresponding to the spaced radius could be derived. The radial stress and plastic shear strain at the inner radius of the outer adjacent annulus were employed to describe the material property evolution law. Then, the radii could be recursively obtained. Finally, for the conventional strain-softening rock masses, the pressure-dependent elastic rock and elasto-plastic coupling strain-softening rock masses were employed to validate the proposed approach. In this study, having completed the above steps, it was concluded that the results were in accordance with the numerical methods.

On the Potential of Limitation-oriented Malware Detection and Prevention Techniques on Mobile Phones

Qiang Yan,Robert H. Deng,Yingjiu Li,Tieyan Li 보안공학연구지원센터 2010 International Journal of Security and Its Applicat Vol.4 No.1

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO₃^-:NH₄⁺ Ratios during the Seedling

Yan, Qiu-Yan,Duan, Zeng-Qiang,Li, Jun-Hui,Li, Xun,Dong, Jin-Long Korean Society of Horticultural Science 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures ($15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$) within a natural aerial temperature ($15-30^{\circ}C$). Four nitrate:ammonium ($NO{_3}^-:NH{_4}^+$) ratios (10:0, 8:2, 5:5, and 2:8 $mmol{\cdot}L^{-1}$) at constant nitrogen (N) concentration of $10mmol{\cdot}L^{-1}$ were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 $NO{_3}^-:NH{_4}^+$ ratio in the $15^{\circ}C$ solution, the 5:5 ratio in the $20^{\circ}C$ solution and the 8:2 ratio in the $25^{\circ}C$ solution. Photosynthetic rate (Pn) response to solution temperature and $NO{_3}^-:NH{_4}^+$ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

Concurrent Weekly Cisplatin Versus Triweekly Cisplatin with Radiotherapy in the Treatment of Cervical Cancer: A Meta-analysis Result

Hu, Yan,Cai, Zhi-Qiang,Su, Xiao-Yan Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Aims: To evaluate the adverse effect and survival outcome of weekly and triweekly cisplatin with radiotherapy in treatment of cervical cancer. Methods: After an extensive literature search between 1995-2011, we analyzed 7 studies to compare weekly cisplatin and triweekly cisplatin combined radiotherapy. Results: Our analysis established that weekly cisplatin has a lower risk of hematologic toxicity than triweekly cisplatin with concurrent radiotherapy in the treatment of cervical cancer. However, there were no differences in progression free survival and overall survival between weekly cisplatin and triweekly cisplatin (p>0.05). Conclusions: Weekly cisplatin combined with concurrent radiation has lower risk in hematologic toxicity than triweekly cisplatin, but does not improve survival. Triweekly cisplatin treatment has longer intervals and is therefore more convenient. Clinicians and patients can choose either weekly cisplatin or triweekly cisplatin combined radiotherapy for cervical cancer.

High selectivity and removal efficiency of lotus root-based activated carbon towards Fe(III) in La(III) solution

Rui-Yan Wu,Yong Wang,Xiao-Yan Xue,Fu-Qiang An,Tuo-Ping Hu,Jian-Feng Gao 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.3

Rare earth elements are an important strategic resource. However, a trace of Fe(III) impurity has serious adverse impact on the performance of rare earth materials. We synthesized a novel nitrogen-containing carbon material, ACLR-400, using lotus root as raw materials. The ACLR-400 was characterized by surface area analyzer, elemental analysis and FT-IR. The selectivity and removal efficiency of ACLR-400 towards Fe(III) were also investigated. The BET specific surface area of ACLR-400 was 68.44m2·g−1, and the average pore diameter was 12.54 nm. With abundant nitrogen- containing functional groups and well-developed internal pore structure, ACLR-400 possesses strong adsorption affinity, excellent selectivity and removal efficiency for Fe(III). The adsorption capacity of ACLR-400 towards Fe(III) could reach to 0.46mmol·g−1, selectivity coefficient with respect to La(III) was 8.9, and removal efficiency was 99.61%. The adsorption isotherm data greatly obey the Freundlich isotherm. In addition, ACLR-400 can be regenerated easily and possesses better regeneration ability and reusability.

Overexpression of Phospholipase A₂ Group IIA in Esophageal Squamous Cell Carcinoma and Association with Cyclooxygenase-2 Expression

Zhai, Yan-Chun,Dong, Bin,Wei, Wen-Qiang,He, Yan,Li, Xin-Qing,Cormier, Robert T.,Wang, Wei,Liu, Fen Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Background: Esophageal cancer is one of the most frequently occurring malignancies and the seventh leading cause of cancer-related deaths in the world. The esophageal squamous cell carcinoma (ESCC) is the most common histological type of esophageal cancer worldwide. Materials and Methods: Our goal in this study was to detect phospholipase A2 Group IIA (PLA2G2A) and cyclooxygenase-2 (COX-2) immuno-expression in ESCC in a high-risk population in China. Results: Positive expression of PLA2G2A protein was observed in 57.2% (166/290) of the cases, while COX-2 was found in 257 of 290 samples (88.6%), both PLA2G2A and COX-2 being expressed in 153 cases (52.8%), with a significant agreement (Kappa=0.091, p=0.031).Overexpression of PLA2G2A was significantly correlated with the depth of invasion (p=0.001). Co-expression of PLA2G2A and COX-2 not only significantly correlated with the depth of invasion (p=0.004) but also with TNM stage (p=0.04). Conclusions: Our results showed that in patients with ESCC, PLA2G2A overexpression and PLA2G2A co-expression with COX-2 is significantly correlated with advanced stage. The biological role and pathophysiologic regulation of PLA2G2A and COX-2 overexpression in ESCC deserve further investigation.

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO₃<SUP>-</SUP>

Qiu-yan Yan,Zeng-qiang Duan,Jun-hui Li,Xun Li,Jin-long Dong 한국원예학회 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures (15°C, 20°C, and 25°C) within a natural aerial temperature (15-30°C). Four nitrate:ammonium (NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP>) ratios (10:0, 8:2, 5:5, and 2:8 mmol・L<SUP>-1</SUP>) at constant nitrogen (N) concentration of 10 mmol・L<SUP>-1</SUP> were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP> ratio in the 15°C solution, the 5:5 ratio in the 20°C solution and the 8:2 ratio in the 25°C solution. Photosynthetic rate (Pn) response to solution temperature and NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP> ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

First Enzymatic Galactosylation of Acyclic Nucleoside Drugs by β-Galactosidase: Synthesis of Water-soluble β-D-Galactosidic Prodrugs

Li-Qiang Yan,Ning Liu,Min-Hua Zong 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.4

Acyclic nucleoside analogs constitute animportant group of antiviral agents. However, thesenucleoside drugs suffer from poor water solubility and loworal bioavailability in the clinic use. In the present work,the enzymatic synthesis of the water-soluble galactosidicprodrugs of acyclic nucleosides by using bovine liverβ-galactosidase was described. In the enzymatic transgalactosylationbetween acyclovir (ACV) and o-nitrophenylβ-galactopyranoside (oNPGal), the optimum enzyme dosage,buffer pH, temperature and molar ratio of ACV to oNPGalwere 0.225 U/mL, 7.0, 40°C and 2.5, respectively, underwhich the initial reaction rate and the yield reached0.40 mM/h and 29%, respectively. In addition, this enzymecould accept ganciclovir (GCV) and penciclovir (PCV) assubstrates, affording the corresponding 4’-β-galactosylatedderivatives with the yields of 26% and 71%, respectively.

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO3-:NH4+ Ratios during the Seedling

Qiu-yan Yan,Zeng-qiang Duan,Jun-hui Li,Xun Li,Jin-long Dong 한국원예학회 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth,photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures (15°C, 20°C, and 25°C) within a natural aerial temperature (15-30°C). Four nitrate:ammonium (NO3-:NH4+) ratios (10:0, 8:2, 5:5, and 2:8 mmol・L-1)at constant nitrogen (N) concentration of 10 mmol・L-1 were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area)in most N treatments. Dry weight accumulation was greatest at the 10:0 NO3-:NH4+ ratio in the 15°C solution,the 5:5 ratio in the 20°C solution and the 8:2 ratio in the 25°C solution. Photosynthetic rate (Pn) response to solution temperature and NO3-:NH4+ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

Overexpression of ENA1 from Yeast Increases Salt Tolerance in Arabidopsis

( Xiang Qiang Kong ),( Xiu Hua Gao ),( Wei Huan Li ),( Ji Qiang Zhao ),( Yan Xiu Zhao ),( Hui Zhang ) 한국식물학회 2008 Journal of Plant Biology Vol.51 No.2

In yeast, the plasma membrane Na+/H+ antiporter and Na+ -ATPase are key enzymes for salt tolerance. Saccharomyces cerevisiae Na+ -ATPase (Ena1p ATPase) is encoded by the ENA1/PMR2A gene; expression of ENA1 is tightly regulated by Na+ and depends on ambient pH. Although Ena1p is active mainly at alkaline pH values in S. cerevisiae, no Na+ -ATPase has been found in flowering plants. To test whether this yeast enzyme would improve salt tolerance in plants, we introduced ENA1 into Arabidopsis (cv. Columbia) under the control of the cauliflower mosaic virus 35S promoter. Transformants were selected for their ability to grow on a medium containing kanamyin. Southern blot analyses confirmed that ENA1 was transferred into the Arabidopsis genome and northern blot analyses showed that ENA1 was expressed in the transformants. Several transgenic homozygous lines and wild-type (WT) plants were evaluated for salt tolerance. No obvious morphological or developmental differences existed between the transgenic and WT plants in the absence of stress. However, overexpression of ENA1 in Arabidopsis improved seed germination rates and salt tolerance in seedlings. Under saline conditions, transgenic plants accumulated a lower amount of Na+ than did the wild type, and fresh and dry weights of the former were higher. Other experiments revealed that expression of ENA1 promoted salt tolerance in transgenic Arabidopsis under both acidic and alkaline conditions.