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Comparative study on glutathione transferases of rat brain and testis under the stress of phenobarbitol and β-methylcholanthrene

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第8期6卷 759-769页

作者： THYAGARAJU k HEMAVATHI B VASUNdHARA k RAO A.d dEVI k.N department of Biochemistry Sri Venkateswara UniversityTirupati 517 502 AP IndiaDepartment of Biochemistry Sri Venkateswara UniversityTirupati 517 502 AP IndiaDepartment of Biochemistry Sri Venkateswara UniversityTirupati 517 502 AP IndiaDepartment of Biochemistry Sri Venkateswara UniversityTirupati 517 502 AP IndiaDepartment of Biochemistry Sri Venkateswara UniversityTirupati 517 502 AP India

A comparative study was made on the tissue specific expression of glutathione transferases (GST) in brain and testis after exposure of rat to phenobarbitol (PB) and β-methylcholanthrene (MC). Glutathione transferases, a family of multifunctional proteins are involved in intracellular transport processes and in detoxication of electrophilic xenobiotics by catalyzing reactions such as conjugation, isomerization, reduction and thiolysis. On purification, the yield of GST proteins by affinity chromatography was 39% in testis and 32% in brain. The affinity purified testis GSTs were resolved by chromatofocusing into six anionic and four cationic isozymes, and in brain glutathione transferases were resolved into four anionic and three cationic isozymes, suggesting the presence of multiple isozymes with Yc, Yb, Yβ and Yδ in both of them. In testis and brain, these isozymes at identical pI values showed variable functions with a battery of substrates and the cationic isozymes of brain and testis showed identical properties in CHP (cumene hydroperoxide) at pH values of above 7.0. Substrate specificity studies and immunoblot analysis of testis and brain proteins revealed that they play a predominant role in the detoxication of phenobarbitol or β-methylcholanthrene. Expression of the isozymes in testis and brain on exposure to PB and MC indicated elevated subunit variation. In both testis and brain, Yδ of π class was expressed on PB treatment and Yc of α class and Yβ of μ class was expressed in MC treated testis and only Yc was predominantly expressed in MC treated brain. Thus these subunits expression is considered as markers for carcinogenesis and specific to chemical toxicity under phenobarbitol and β-methylcholanthrene stress.

关键词： Glutathione transferases Testis Brain Phenobarbitol β-Methylcholanthrene

A Lower Bound on Longitudinal Structure Function at Small x from a Self-Similarity Based Model of Proton

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Communications in Theoretical Physics 2014年第5期61卷 654-658页

作者： Akbari Jahan d.k.Choudhury department of Physics Gauhati University

Self-similarity based model of proton structure function at small x was reported in the literature sometime back. The phenomenological validity of the model is in the kinematical region 6.2 × 10-7 ≤ x ≤ 10-2 and 0.045 ≤ Q2 ≤ 120 GeV2. We use momentum sum rule to pin down the corresponding self-similarity-based gluon distribution function valid in the same kinematical region. The model is then used to compute bound on the longitudinal structure function FL（X, Q2） for A1tarelli-Martinelli equation in QCd and is compared with the recent HERA data.

关键词： self-similarity small x longitudinal structure function QCd

GENERALIZEd FRACTIONAL CALCULUS OF THE ALEPH-FUNCTION INVOLVING A GENERAL CLASS OF POLYNOMIALS

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Acta Mathematica Scientia 2015年第5期35卷 1095-1110页

作者： R.k.SAXENA d.kUMAR department of Mathematics and Statistics Jai Narain Vyas University

The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-function, Appell function F3 and a general class of poly- nomials. The results obtained provide unification and extension of the results given by Saxena et al. [13], Srivastava and Grag [17], Srivastava et al. [20], and etc. The results are obtained in compact form and are useful in preparing some tables of operators of fractional calculus. On account of the general nature of the Saigo-Maeda operators, R-function, and a general class of polynomials a large number of new and known results involving Saigo fractional calculus operators and several special functions notably H-function, /-function, Mittag-Leffier function, generalized Wright hypergeometric function, generalized Bessel-Maitland function follow as special cases of our main findings.

关键词： generalized fractional calculus operators a general class of polynomials R-function H-function /-function generalized Wright hypergeometric function Mittag-Leffler function generalized Bessel-Maitland function

Generalized Multiobjective Symmetric duality under Second-Order(F, α, ρ, d)-Convexity

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 529-542页

作者： S.k.Gupta d.dangar department of Mathematics Indian Institute of Technology Roorkee department of Mathematics and Humanities IT Nirma University

In this paper, we first formulate a second-order multiobjective symmetric primal-dual pair over arbitrary cones by introducing two different functions f ： R^n × R^m → Rk and g ： R^n × R^m → R^l in each k-objectives as well as l-constraints. Further, appropriate duality relations are established under second-order（F, α, ρ, d）-convexity assumptions. A nontrivial example which is second-order（F, α, ρ, d）-convex but not secondorder convex/F-convex is also illustrated. Moreover, a second-order minimax mixed integer dual programs is formulated and a duality theorem is established using second-order（F, α, ρ, d）-convexity assumptions. A self duality theorem is also obtained by assuming the functions involved to be skew-symmetric.

关键词： multiobjective symmetric duality second-order(F α ρ d)-convex duality theorems minimax self duality

Propagation of plane waves in poroviscoelastic anisotropic media

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Applied Mathematics and Mechanics(English Edition) 2008年第9期29卷 1141-1153页

作者： A.k.Vashishth M.d.Sharma department of Mathematics Kurukshetra University

This study discusses wave propagation in perhaps the most general model of a poroelastic medium. The medium is considered as a viscoelastic, anisotropic and porous solid frame such that its pores of anisotropic permeability are filled with a viscous fluid. The anisotropy considered is of general type, and the attenuating waves in the medium are treated as the inhomogeneous waves. The complex slowness vector is resolved to define the phase velocity, homogeneous attenuation, inhomogeneous attenuation, and angle of attenuation for each of the four attenuating waves in the medium. A non-dimensional parameter measures the deviation of an inhomogeneous wave from its homogeneous version. An numerical model of a North-Sea sandstone is used to analyze the effects of the propagation direction, inhomogeneity parameter, frequency regime, anisotropy symmetry, anelasticity of the frame, and viscosity of the pore-fluid on the propagation characteristics of waves in such a medium.

关键词： inhomogeneous waves anisotropy poroviscoelastic solid phase velocity,attenuation

Macronutrients and Health—Steps to Ameliorating the Nutrition Transition Trap

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Biomedical and Environmental Sciences 2001年第1期14卷 124-129页

作者： d. C. k. ROBERTS School of Health Sciences Faculty of Medicine and Health Sciences

Countries that have made the health transition from a communicable disease base to a non communicable disease base find themselves gripped in an epidemic of wealth created diseases mediated by altered macronutrient intakes, energy intakes and reduction in physical activity. Avoiding the negative impact of the nutrition transition while accepting the positive aspects of the wealth transition can best be achieved by focussing on publicising the benefits of a low fat diet in the context of an active lifestyle. How this is achieved should reflect ecologically sound food production appropriate to national needs. Countries that achieve this will be in the best position to capitalize on the reduction in communicable disease rates without causing a rise in non communicable disease rates.

关键词： physical activity food production

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基于热传导逆问题方法预测材料热物性参数

化工学报 2005年第12期56卷 2415-2420页

作者：杨晨 Ulrich gross 重庆大学动力工程学院重庆400044 弗赖贝格工业大学热力学研究所德国弗赖贝格09599

建立了一种应用LevenbergMarquardt迭代过程求解非线性热传导逆问题用于预测材料热物性的方法.以平板内的一维非稳态热传导为研究对象,在准确的数值计算结果上施加非均匀随机误差来模拟瞬态温度实验数据,应用该方法分别对热传导系数为... 详细信息

建立了一种应用LevenbergMarquardt迭代过程求解非线性热传导逆问题用于预测材料热物性的方法.以平板内的一维非稳态热传导为研究对象,在准确的数值计算结果上施加非均匀随机误差来模拟瞬态温度实验数据,应用该方法分别对热传导系数为常数、热传导系数和容积比热容为常数以及热传导系数和容积比热容为温度的函数3种情况进行了预测.参数预测结果表明,方法对基于瞬态实验方法进行热物性预测具有良好的适应性,并适用于分析多类热传导逆问题,该方法还能为优化实验提供有效信息.

关键词：热传导逆问题热物性参数预测 Levenberg-Marquardt方法

Stokes flow of micro-polar fluids by peristaltic pumping through tube with slip boundary condition

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Applied Mathematics and Mechanics(English Edition) 2011年第12期32卷 1587-1598页

作者： d.TRIPATHI M.k.CHAUBE P.k.GUPTA department of Mathematics Indian Institute of Technology Ropar Punjab 140001 India department of Mathematics Raj Kumar Goel Institute of Technology Ghaziabad 201001 India department of Applied Mathematics Institute of Technology Banaras Hindu University Varanasi 221005 India

This paper studies the Stokes flow of micro-polar fluids by peristaltic pumping through the cylindrical tube under the effect of the slip boundary condition. The motion of the wall is governed by the sinusoidal wave equation. The analytical and numerical solutions for the axial velocity, the micro-polar vector, the stream function, the pressure gradient, the friction force, and the mechanical efficiency are obtained by using the lu- brication theory under the low Reynolds number and long wavelength approximations. The impacts of the emerging parameters, such as the coupling number, the micro-polar parameter, the slip parameter on pumping characteristics, the friction force, the velocity profile, the mechanical efficiency, and the trapping phenomenon are depicted graphically. The numerical results infer that large pressure is required for peristaltic pumping when the coupling number is large, while opposite behaviors are found for the micro-polar parameter and the slip parameter. The size of the trapped bolus reduces with the increase in the coupling number and the micro-polar parameter, whereas it blows up with the increase in the slip parameter.

关键词： Stokes flow slip boundary condition mechanical efficiency micro-polarfluid peristaltic pumping trapping

deep mine cooling,a case for Northern Ontario:Part Ⅰ

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International Journal of Mining Science and Technology 2016年第6期26卷 721-727页

作者： d. Millar k. Trapani A. Romero MIRARCO 935 Ramsey Lake Rd Sudbury P3E 2C6 Canada Laurentian University 935 Ramsey Lake Rd Sudbury P3E 2C6 Canada

Cooling energy needs, for mines in Northern Ontario, are mainly driven by the mining depth and its operation. Part I of this research focusses on the thermal energy loads in deep mines as a result of the virgin rock temperature, mining operations and climatic conditions. A breakdown of the various heat sources is outlined, for an underground mine producing 3500 tonnes per day of broken rock, taking into consideration the latent and sensible portions of that heat to properly assess the wet bulb global temperature. The resulting thermal loads indicate that cooling efforts would be needed both at surface and underground to maintain the temperature underground within the legal threshold. In winter the air might also have to be heated at surface and cooled underground, to ensure that icing does not occur in the inlet ventilation shaft-the main reason why coolin~ cannot be focussed solely at surface.

关键词： Thermal loads Cooling Underground mining deep mining HVAC mining

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