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Sharif M.,University of Punjab | Azam M.,University of Punjab | Azam M.,University of Education of Pakistan
Monthly Notices of the Royal Astronomical Society | Year: 2013

We study the dynamical instability of anisotropic collapsing cylinder with the expansion-free condition, which generates vacuum cavity within fluid distribution. The perturbation scheme is applied to distinguish Newtonian, post-Newtonian and post-post Newtonian terms, which are used for constructing dynamical equation at Newtonian and post-Newtonian regimes. We analyse the role of pressure anisotropy and energy density inhomogeneity on the stability of collapsing cylinder. It turns out that stability of the cylinder depends upon these physical properties of the fluid, not on the stiffness of the fluid. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Sharif M.,University of Punjab | Azam M.,University of Education of Pakistan
European Physical Journal C | Year: 2013

In this paper, we apply the cut and paste procedure to the charged black string for the construction of a thin-shell wormhole. We consider the Darmois-Israel formalism to determine the surface stresses of the shell. We take the Chaplygin gas to deal with the matter distribution on shell. The radial perturbation approach (preserving the symmetry) is used to investigate the stability of static solutions. We conclude that stable static solutions exist both for uncharged and charged black string thin-shell wormholes for particular values of the parameters. © 2013 Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica.

Sharif M.,University of Punjab | Azam M.,University of Punjab | Azam M.,University of Education of Pakistan
Journal of the Physical Society of Japan | Year: 2012

In this paper, we construct thin-shell wormholes by applying the cut and paste procedure to a regular charged black hole in nonlinear electrodynamics field. We discuss different physical aspects of wormholes such as, the possible equation of state to matter shell, attractive or repulsive nature of wormhole and total amount of exotic matter required. The thin-shell equation of motion with and without cosmological constant is also investigated under linearized perturbation. Finally, we explore the stability regions interpreted by the parameter β (speed of sound) and conclude that there are realistic stability regions for some fixed values of parameters. ©2012 The Physical Society of Japan.

Liu H.-Y.,South China University of Technology | Mahmood M.H.R.,South China University of Technology | Mahmood M.H.R.,University of Education of Pakistan | Qiu S.X.,CAS South China Botanical Garden | Chang C.K.,Michigan State University
Coordination Chemistry Reviews | Year: 2013

Among metallocorroles, manganese corrole chemistry is one that has flourished prominently in recent years. Numerous manganese corroles have been reported in which the oxidation state of the central manganese ranges from +3 to +6. Manganese(III) corroles are the most common form of stable Mn-corrole complexes. High-valent manganese corroles exhibit quite different spectroscopic and electrochemical properties compared with manganese(III) corroles. (Imido)manganese(V) and (nitrido)manganese(V) corroles are stable enough to be well characterized by spectroscopy. (Oxo)manganese(V) corroles may be prepared by chemical or laser flash photolysis methods, and are important mechanistic probes for oxygen atom transfer reactions in the catalytic oxidation of alkenes. While various (oxo)manganese complexes have been synthesized and extensively studied, the factors controlling their reactivity are not completely understood, suggesting that manganese corrole-mediated oxidation reactions have room for further exploration. In this review, recent advances in the field of manganese corroles are summarized. © 2013 Elsevier B.V.

Safa Y.,University of Agriculture at Faisalabad | Safa Y.,University of Education of Pakistan | Bhatti H.N.,University of Agriculture at Faisalabad
Chemical Engineering Research and Design | Year: 2011

The present work describes the biosorption potential of low cost and easily available rice husk for the adsorptive removal of Direct Red-31 and Direct Orange-26 textile dyes. In the present investigation a 5 3 full factorial design analysis experiment was employed to optimize the process parameters for enhanced adsorptive removal of Direct Red-31 and Direct Orange-26 textile dyes from aqueous solution. Factorial experiments with three factors initial dye concentration, biosorbent dose and pH at five levels were conducted in duplicate. The biosorbent efficiency for the dyes was determined after 3h of treatment at 30°C using suitable size of biosorbent (0.255mm). Analysis of variance (ANOVA), F-test and p-values were used to study the main, two ways and three ways interaction effects. The values of regression coefficients (R 2=0.999) for both dyes confirmed the good fitness of model. A maximum biosorption capacity of 57.88 and 36.14mg/g was observed at pH 2 and 3 for Direct Red-31 and Direct Orange-26, respectively, with 125mg/L dyes concentration. The most significant variable was found to be dyes initial concentration. Moreover, the decolorization of both direct dyes was also affected by salts, heavy metal ions and surfactants. © 2011 The Institution of Chemical Engineers.

Malik S.,Quaid-i-Azam University | Amin-Ud-din M.,University of Education of Pakistan
Pakistan Journal of Zoology | Year: 2013

Southern Punjab in Pakistan is a heterogeneous assemblage of human populations which have diverse origins. Various waves of pre- and post-partition (1947) migrations, urbanization and high inbreeding coefficient have profoundly influenced the diversity and substructuring of this multiethnic and multilinguistic population. In order to get an insight into the genetic structure of Southern Punjab population, we have employed classical immuno-genetic markers of ABO and Rh loci. Five administrative districts, i.e., Dera Ghazi Khan, Muzaffargarh, Multan, Bahawalpur, and Liaquatpur, were included in this study and the phenotypic and genotypic data of approximately 60,000 subjects was assembled. Various genetic parameters including maximum likelihood estimates of allelic frequencies, Hardy-Weinberg Equilibrium, locus specific and combined heterozygosities, and phenotypic and allelic variances, were investigated to understand population dynamics. Affinities between recruited populations were measured through tests of homogeneity, and gene diversity and coefficient of gene differentiation was computed in sub- and total-population. These analyses established that Southern Punjab population is markedly distinct from the upper Punjab/Punjab populations for the genetic systems studied. Additionally, population stratification and substructuring were significantly higher in Southern Punjab compared to upper Punjab/Punjab, depicting the likely role of micro-evolutionary forces shaping the dynamics of this interesting population. This pilot study would help understand the genetic structure of Southern Punjab population and to find its affinities with other Pakistani populations. Copyright 2013 Zoological Society of Pakistan.

Ahmed Z.,University of Education of Pakistan
Rawal Medical Journal | Year: 2015

Test anxiety is an arising issue of today's academia. Present research attempted to explore its hidden realities in view of types, causes, prevalence, impact and coping mechanism. Test anxiety and educational performance has an inverse relation. General prevalence has been estimated from 30 to 40 percent in all schools. Female students have more anxiety as compared to male students. Major causes arise from parental attitudes, expectations of high grades, admission in good institutions, job market, work load, lack of preparation, inappropriate test techniques and home-school maladjustment. This problem may be addressed through simulation, yoga, behavior modification, therapeutic approaches, guidance and counseling. Pharmacological measures are effective in severe symptoms only. © 2015 Pakistan Medical Association. All right received.

Amir M.J.,University of Sargodha | Ali S.,University of Education of Pakistan
International Journal of Theoretical Physics | Year: 2015

The energy density of the universe is proportional to the Ricci scalar curvature in the dynamical Chern-Simon (CS) modified gravity. In this paper, we consider the Amended Friedman-Robertson-Walker (AFRW) universe and explore its scale factor and the Ricci Dark Energy. These turned out to be well-defined and definite. We compare the scale factors of FRW, Generalized Chaplygin gas (GCG) and AFRW models graphically. The combined graph of these models show that the behavior of both FRW and AFRW models is similar as these overlap each other for choosing particular values of the integration constants. Also, we draw a combined graph of the Ricci dark energy densities of FRW and AFRW models, in CS gravity, and the energy density of GCG. It shows that the densities of former two models are increasing with time while the energy density of GCG is decreasing. © 2014, Springer Science+Business Media New York.

Mansha M.,University of Education of Pakistan
Molecular biology reports | Year: 2012

Our laboratory has developed a series of Gateway(®) compatible lentiviral expression systems for constitutive and conditional gene knock-down and over-expression. For tetracycline-regulated transgenic expression, we constructed a lentiviral "DEST" plasmid (pHR-TetCMV-Dest-IRES-GFP5) containing a tetracycline-responsive minimal CMV promoter, followed by an attP site-flanked DEST cassette (for efficient cloning of cDNAs by "Gateway(®)" recombination cloning) and green fluorescent protein (GFP) driven by an internal ribosomal entry site (IRES).This lentiviral bicistronic plasmid allows immediate FACS identification and characterization of successfully transfected cell lines. Although this system worked well with several cDNAs, we experienced serious problems with SLA, Bam and BMF. Particularly, we cloned the cDNA for human SLA (Src-like adapter), a candidate gene in GC-induced apoptosis, into this plasmid. The resulting construct (pHR-TetCMV-SLA-IRES-GFP5) was transfected into HEK 293-T packaging cells to produce viral particles for transduction of CEM-C7H2-2C8 cells. Although the construct produced many green fluorescent colonies at the HEK 293-T and the CEM-C7H2-2C8 level, we could not detect any SLA protein with α-SLA antibody from corresponding cell lysates. In contrast, the antibody readily detected SLA in whole cell lysate of HEK 293-T cells transfected with a GST-flagged SLA construct lacking IRES-GFP. To directly address the potential role of the IRES-GFP sequence, we cloned the SLA coding region into pHR-TetCMV-Dest, a vector that differs from pHR-TetCMV-Dest-IRES-GFP5 just by the absence of the IRES-GFP cassette. The resulting pHR-TetCMV-SLA construct was used for transfection of HEK 293-T cells. Corresponding lysates were assayed with α-SLA antibody and found positive. These data, in concert with previous findings, suggest that the IRES-GFP cassette may interfere with translation of certain smaller size cDNAs (like SLA) or generate fusion proteins and entail defective virus production in an unpredictable manner.

University of Education of Pakistan | Date: 2011-04-19

Copper is chemically extracted from crude ores by first roasting it at temperature up to 500 C. for 90 minutes, then treating it with ammonium salt followed by leaching with sulfuric acid to obtain a soluble copper mass for further purification.

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