Islamabad, Pakistan

Quaid-i-Azam University

www.qau.edu.pk
Islamabad, Pakistan

The Quaid-i-Azam University , is a public research university located in Islamabad, Pakistan. Consisting of four faculties, nine affiliated research institutes, the university is consistently ranked as the top university in Pakistan " by the HEC and is ranked by Quacquarelli Symonds ranking among the top 500 universities in the world in 2013, while it was ranked at 69th top university of the world in field of 'Engineering and Technology'.With overall ~7,800 students currently attending the university, it offers undergraduate, post-graduate, and doctoral programmes in various academic disciplines. The Quaid-i-Azam University scholars have played critical role in the development of various academic disciplines including in social and natural science. Its school of social science is well known for its leading contribution to the movement in critical analysis. Also, the university's school of natural science holds an international prestige for its leading and developmental role in physics and mathematics since its establishment.Covering the approximated area of 1700 acres below the Margalla Hills, the university is internationally known for its higher learning, technological advancement, and intellectual interaction with a joint collaboration in various academic discipline with various international institutes, including the United Nations. It is one of the most popular universities in the country and has attracted world renowned scholars and intellectuals to serve as faculty, researchers, or alumni since its establishment in 1967. Wikipedia.


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Quantum discord quantifies the total non-classical correlations in mixed states. It is the difference between total correlation, measured by quantum mutual information, and the classical correlation. Another step forward towards the quantification of quantum discord was by Dakić et al. (Phys Rev Lett 105:190502, 2010) who introduced the geometric measure of quantum discord (GMQD) and derived an explicit formula for a two-qubit state. Recently, Luo and Fu (Phys Rev Lett 106:120401, 2011) introduced measurement-induced nonlocality (MIN) as a measure of nonlocality for a bipartite quantum system. The dynamics of GMQD is recently considered by Song et al. (arXiv: quant/ph.1203.3356) and Zhang et al. (Eur Phys J D 66:34, 2012) for inertial observers. However, the topic requires due attention in noninertial frames, particularly, from the perspective of MIN. Here I consider X -structured bipartite quantum system in noninertial frames and analyze the decoherence dynamics of GMQD and MIN at finite temperature. The dynamics under the influence of amplitude damping, depolarizing and phase flip channels is discussed. It is worth-noting that initial state entanglement plays an important role in bipartite states. It is possible to distinguish the Bell, Werner and general type initial quantum states using GMQD. Sudden transition in the behaviour of GMQD and MIN occurs depending upon the mean photon number of the local environment. The transition behaviour disappears for larger values of n̄ i.e. n̄ > 0.3 It becomes more prominent, when environmental noise is introduced in the system. In the presence of environmental noise, as we increase the value of acceleration r, GMQD and MIN decay due to Unruh effect. The effect is prominent for the phase flip and amplitude damping channels. However, in case of depolarizing channel, no sudden change in the behaviour of GMQD and MIN is observed. The environmental noise has stronger affect on the dynamics of GMQD and MIN as compared to the Unruh effect. Furthermore, Werner like states are more robust than General type initial states at finite temperature. © 2013 Springer Science+Business Media New York.


Mahmood T.,Quaid-i-Azam University
International Journal of Economics and Financial Issues | Year: 2012

β -convergence and the speed of convergence of labour productivity for 52 industries are studied with a panel of data including 13 European countries. We use fixed effect approach to model the heterogeneity across countries. In primary sector and in service sector, the existence of β - convergence is found for all industries. In manufacturing sector, convergence is found for all industries except for electronic and computing equipment industries. In general the speed of convergence estimates show slow adjustment. Speed is highest in the capital intensive industries. In primary production the convergence is slowest in agriculture and fastest in fishing industry. In manufacturing sector the convergence is slowest in food, drink and tobacco, and it is fastest in oil refining and nuclear fuel manufacturing industries. By augmenting the productivity models with labour utilization variable speeds up the convergence. Labour utilization is positively related to productivity growth in primary production industries, ICT producing manufacturing industries, and ICT producing services industries. © 2012, Econjournals. All rights reserved.


Ramzan M.,Quaid-i-Azam University
Quantum Information Processing | Year: 2013

Effect of decoherence and correlated noise on the entanglement of X-type state of the Dirac fields in the non-inertial frame is investigated. A two qubit X-state is considered to be shared between the partners where Alice is in inertial frame and Rob in an accelerated frame. The concurrence is used to quantify the entanglement of the X-state system influenced by time correlated amplitude damping, depolarizing and bit flip channels. It is seen that amplitude damping and bit flip channels heavily influence the entanglement of the system as compared to the depolarizing channel. It is found possible to avoid entanglement sudden death (ESD) for all the channels under consideration for μ > 0.75 for any type of initial state. No ESD behaviour is seen for depolarizing channel in the presence of correlated noise for entire range of decoherence parameter p and Rob's acceleration r. It is also seen that the effect of environment is much stronger than that of acceleration of the accelerated partner. Furthermore, it is investigated that correlated noise compensates the loss of entanglement caused by the Unruh effect. © 2012 Springer Science+Business Media, LLC.


Nawaz A.,Quaid-i-Azam University
Journal of Physics A: Mathematical and Theoretical | Year: 2012

We quantize prisoners' dilemma in the presence of collective dephasing with a dephasing rate γ. It is shown that for a two-parameter set of strategies, Q⊗Q is Nash equilibrium below a cut-off value of time. Beyond this cut-off it bifurcates into two new Nash equilibria Q⊗D and D⊗Q. Furthermore, for the maximum value of decoherence C⊗D and D⊗C also become Nash equilibria. At this stage the game has four Nash equilibria. On the other hand, for a three-parameter set of strategies, there is no pure strategy Nash equilibrium; however, there is a mixed strategy (non-unique) Nash equilibrium that is not affected by collective dephasing. © 2012 IOP Publishing Ltd.


Malik S.,Quaid-i-Azam University
European Journal of Human Genetics | Year: 2012

Syndactyly is one of the most common hereditary limb malformations depicting the fusion of certain fingers and/or toes. It may occur as an isolated entity or a component of more than 300 syndromic anomalies. Syndactylies exhibit great inter-and intra-familial clinical variability. Even within a subject, phenotype can be unilateral or bilateral and symmetrical or asymmetrical. At least nine non-syndromic syndactylies with additional sub-types have been characterized. Most of the syndactyly types are inherited as autosomal dominant but two autosomal recessive and an X-linked recessive entity have also been described. Whereas the underlying genes/mutations for types II-1, III, IV, V, and VII have been worked out, the etiology and molecular basis of the other syndactyly types remain unknown. In this communication, based on an overview of well-characterized isolated syndactylies, their cardinal phenotypes, inheritance patterns, and clinical and genetic heterogeneities, a current classification scheme is presented. Despite considerable progress in the understanding of syndactyly at clinical and molecular levels, fundamental questions regarding the disturbed developmental mechanisms leading to fused digits, remain to be answered. © 2012 Macmillan Publishers Limited All rights reserved.


Khan S.A.,Quaid-i-Azam University
Physics of Plasmas | Year: 2012

Low frequency electrostatic and electromagnetic waves are investigated in ultra-dense quantum magnetoplasma with relativistic-degenerate electron and non-degenerate ion fluids. The dispersion relation is derived for mobile as well as immobile ions by employing hydrodynamic equations for such plasma under the influence of electromagnetic forces and pressure gradient of relativistic-degenerate Fermi gas of electrons. The result shows the coexistence of shear Alfven and ion modes with relativistically modified dispersive properties. The relevance of results to the dense degenerate plasmas of astrophysical origin (for instance, white dwarf stars) is pointed out with brief discussion on ultra-relativistic and non-relativistic limits. © 2012 American Institute of Physics.


Irfan Ali M.,Quaid-i-Azam University
Applied Soft Computing Journal | Year: 2011

Concept of an approximation space associated with each parameter in a soft set is discussed and an approximation space associated with the soft set is defined. For any subset X of the universe U, there is a fuzzy subset of U associated with each parameter of the soft set, also there is a fuzzy subset associated with the soft set. Furthermore each soft set over a set U, gives rise to a fuzzy soft set over P(U) and induces a soft equivalence relation over P(U). © 2011 Elsevier B.V.


Malik S.,Quaid-i-Azam University
Clinical Genetics | Year: 2014

Polydactyly is one of the most common hereditary limb malformations featuring additional digits in hands and/or feet. It constituted the highest proportion among the congenital limb defects in various epidemiological surveys. Polydactyly, primarily presenting as an additional pre-axial or post-axial digit of autopod, is a highly heterogeneous condition and depicts broad inter- and intra-familial clinical variability. There is a plethora of polydactyly classification methods reported in the medical literature which approach the heterogeneity in polydactyly in various ways. In this communication, well-characterized, non-syndromic polydactylies in humans are reviewed. The cardinal features, phenotypic variability and molecular advances of each type have been presented. Polydactyly at cellular and developmental levels is mainly a failure in the control of digit number. Interestingly, GLI3 and SHH (ZRS/SHH enhancer), two antagonistic factors known to modulate digit number and identity during development, have also been implicated in polydactyly. Mutations in GLI3 and ZRS/SHH cause overlapping polydactyly phenotypes highlighting shared molecular cascades in the etiology of additional digits, and thus suggesting the lumping of at least six distinct polydactyly entities. However, owing to the extreme phenotypic and clinical heterogeneity witnessed in polydactyly a substantial genetic heterogeneity is expected across different populations and ethnic groups. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.


Hussain I.,Quaid-i-Azam University
Mathematical and Computer Modelling | Year: 2013

In this letter, we present a new audio watermarking technique using S-box transformation. Furthermore, we analyze the strength of the proposed watermarking technique with MSE analysis, PSNR analysis, SSIM analysis, robustness analysis, compression attack analysis, noise attack analysis, cropping analysis and capacity analysis and conclude that the proposed method of watermarking is better than many existing techniques. © 2012 Elsevier Ltd.


Ramzan M.,Quaid-i-Azam University
European Physical Journal D | Year: 2013

Quantum discord is an optimal resource for the measure of classical and non-classical correlations as compared to other related measures. Geometric measure of quantum discord is another measure of quantum correlations. Recently, the geometric quantum discord (GQD) for multipartite states has been introduced by Xu [J. Phys. A: Math. Theor. 45, 405304 (2012)]. Motivated from the recent study [M.-L. Hu, H. Fan, Ann. Phys. 327, 851 (2012)] for the bipartite systems, I have investigated global quantum discord (QD) and geometric quantum discord (GQD) under the influence of external environments for different multipartite states. Werner-GHZ type three-qubit and six-qubit states are considered in inertial and non-inertial settings. The dynamics of QD and GQD is investigated under amplitude damping, phase damping, depolarizing and flipping channels. The vanishing behaviour of quantum discord is seen for higher level of decoherence, i.e. the behaviour is prominent for p > 0.75 in case of three-qubit GHZ states and for p > 0.5 for six qubit GHZ states. This implies that multipartite states are more fragile to decoherence for higher values of N. Surprisingly, a rapid fall and rise of quantum discord occurs in case of phase flip channel at p = 0.5. However, the behaviour is avoidable in case of bit flip channel for the six-qubit GHZ states. On the other hand, depolarizing channel heavily influences the QD and GQD as compared to the amplitude damping channel. It means that the depolarizing channel has the most destructive influence on the discords for multipartite states. It is also seen that the QD and GQD manifest the phenomena of sudden transition and freeze in the presence of flipping noise. From the perspective of accelerated observers, it is seen that effect of environment on QD and GQD is much stronger than that of the acceleration of non-inertial frames. The degradation of QD and GQD happens due to Unruh effect. Furthermore, QD exhibits more robustness than GQD when the multipartite systems are exposed to environment. © 2013 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.

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