Allama Iqbal Open University

Islamabad, Pakistan

Allama Iqbal Open University

Islamabad, Pakistan

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Saeed S.,Allama Iqbal Open University | Rashid N.,Allama Iqbal Open University | Jones P.G.,TU Braunschweig | Ali M.,University of Punjab | Hussain R.,National Engineering and Scientific Commission
European Journal of Medicinal Chemistry | Year: 2010

Five series of thiourea derivatives bearing benzothiazole moiety (20 compounds) were efficiently synthesized and evaluated for antimicrobial and anticancer activities. The results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms and showed higher activity against fungi than bacteria. Compounds 1b, 2b, 3b, 4b and 5b exhibited the greatest antimicrobial activity. Preliminary study of the structure-activity relationship revealed that electronic factors in benzothiazole rings had a great effect on the antimicrobial activity of these compounds. In preliminary MTT cytotoxicity studies, the thiourea derivatives (2d, 5c and 5d) were found most potent. In MCF-7 and HeLa cells, the IC 50 values were observed in the range of 18-26 μM and 38-46 μM, respectively. © 2009 Elsevier Masson SAS. All rights reserved.

Saeed S.,Allama Iqbal Open University | Jasinski J.P.,Keene State College | Butcher R.J.,Howard University
Acta Crystallographica Section E: Structure Reports Online | Year: 2011

In the title compound, C 13H 9BrN 2O 3, the dihedral angle between the mean planes of the two benzene rings is 3.6 (7)°. The amide group is twisted by 28.1 (6) and 31.8 (3)° from the mean planes of the 4-bromophenyl and 4-nitrobenzene rings, respectively. The crystal packing features weak intermolecular N -H⋯O and C -H⋯O hydrogen bonds resulting in a threedimensional network.

Xavier T.S.,Center for Molecular and Biophysics Research | Rashid N.,Allama Iqbal Open University | Hubert Joe I.,Center for Molecular and Biophysics Research
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2011

FT-IR and FT-Raman spectra of the 2-(4-Bromophenyl)-1H-benzimidzole were recorded and analyzed in the solid phase. The optimized molecular geometry, the vibrational wavenumbers, the infrared intensities and the Raman scattering activities were calculated by using Hartree-Fock and density functional method (B3LYP) with 6-31G(d,p) basis set. The potential surface scan study was carried out for the conformation of theoretical structure. Detailed interpretation of the vibrational spectra had been carried out with the aid of the normal coordinate analysis. Chemical interpretation of hyperconjugative interaction was done by natural bond orbital analysis. © 2010 Elsevier B.V. All rights reserved.

Ahmad L.,Allama Iqbal Open University | Aslam M.,Forman Christian College | Jun C.-H.,Pohang University of Science and Technology
Transactions of the Institute of Measurement and Control | Year: 2014

A control chart, being an important tool of statistical process control, has been used for process monitoring and detection of any out-of-control process situation. In this paper, the Shewhart X̄ chart, also known as the traditional control chart, in combination with the process capability index Cp proposed by Subramani and Balamurali, is presented under the repetitive sampling scheme. The optimal design parameters of the proposed control chart are calculated. The performance of the proposed control chart is evaluated through the average run lengths (ARLs). Numerical tables have been constructed for the purpose of comparing the in-control ARL and the out-of-control ARL with the single sampling scheme. The findings of the study show that the newly suggested sampling scheme is better than the existing single sampling scheme in detection of mean shift of the process. © The Author(s) 2013.

A series of variously substituted 1,3-thiazole heterocyclic compounds (3a-3d) were prepared by base-catalyzed S-cyclization of corresponding 2,4-dichloro-N-{[(4-substitutedphenyl)amino]carbonothioyl}benzamide (2a-2d) with acetophenone in the presence of bromine. The structure of all compounds was established by IR, 1H-NMR, 13C-NMR, elemental analysis, and X-ray crystallographic analysis. © 2012 Hetero Corporation.

Arif M.,Allama Iqbal Open University | Mahmood K.,University of Punjab
Electronic Library | Year: 2012

Purpose -The aim of this study was to explore the pattern and extent of the adoption of Web 2.0 technologies by Pakistani librarians. Design/methodology/ approach -A survey was conducted using web-based surveying software (SurveyMonkey) and Pakistan based LIS e-mail discussion groups. Professional librarians serving in all types of libraries participated in the study. Findings -Instant messaging, blogs, social networking and wikis were the most popular Web 2.0 technologies. Librarians adopted such technologies in their professional and personal lives. Gender, length of professional experience and place of work have no effect on the frequency of use, while perceived skill level of internet use and perceived ease of Web 2.0 use have a significant effect on the frequency. Lack of computer literacy, and lower availability of computers and internet facilities were the major hindrances of Web 2.0 adoption by librarians. Awareness and training programs could enable librarians to cope with Web 2.0 technologies. Research limitations/implications -Due to the use of a non-probability/non-representative sampling method, the results cannot be generalized. Practical implications -This study will create awareness among LIS professionals toward the use of advanced technology in their professional environment. The findings of this study will contribute to the successful adoption of Web 2.0 in libraries. Originality/value -This is the first study on the adoption of Web 2.0 technologies in Pakistani librarianship. © Emerald Group Publishing Limited.

Arshad N.,Allama Iqbal Open University | Yunus U.,Allama Iqbal Open University | Razzque S.,Allama Iqbal Open University | Khan M.,Allama Iqbal Open University | And 3 more authors.
European Journal of Medicinal Chemistry | Year: 2012

Interaction and binding of isonicotinic acid hydrazide (INH) and its two analogs; pyrazine carboxylic acid hydrazide (PCH) and 2,4-dihydroxy benzoic acid hydrazide (2,4-DHBAH) with DNA has been investigated by UV-spectroscopy and cyclic voltammetry (CV) at physiological conditions of pH and temperature. Experimental results from both techniques were in good agreement and indicated stronger binding and formation of hydrazides-DNA complexes via intercalation. Among three hydrazides, 2,4-DHBAH showed greater interaction toward DNA at stomach pH (4.7) as evident from its comparatively greater binding constant, {K b; 2.02 × 10 4 M -1 (UV), 3.13 × 10 4 M -1 (CV)}. The greater binding site size (n = 3) for 2,4-DHBAH at stomach pH inferred 3:1 binding stoichiometry and possibility of electrostatic interactions or hydrogen bonding along with intercalative mode of interaction between 2,4-DHBAH and DNA. The free energies of hydrazides-DNA complexes indicated the spontaneity of their binding. 2,4-DHBAH has shown promising anti-bacterial activities while anti-oxidant and cytotoxic potentials were exhibited by all three hydrazides. © 2011 Elsevier Masson SAS. All rights reserved.

Arshad N.,Allama Iqbal Open University | Farooqi S.I.,Allama Iqbal Open University | Bhatti M.H.,Allama Iqbal Open University | Saleem S.,Quaid-i-Azam University | Mirza B.,Quaid-i-Azam University
Journal of Photochemistry and Photobiology B: Biology | Year: 2013

A carboxylic acid ligand, (Z)-4-(4-acetylphenylamino)-4-oxobut-2-enoic acid (APA-1), and its triphenyl-(APA-2) and tributyl-tin(IV) (APA-3) compounds have been synthesized and investigated for their binding with ds.DNA using UV-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and viscosity measurements under physiological conditions of pH and temperature. The experimental results from all techniques i.e. binding constant (Kb), binding site size (n) and free energy change (ΔG) were in good agreement and inferred spontaneous compound-DNA complexes formation via intercalation. Among all the compounds APA-3 showed comparatively greater binding at pH 4.7 as evident from its greater Kb values {APA-3: Kb: 5.63 × 104 M-1 (UV); 7.94 × 104 M -1 (fluorescence); 9.91 × 104 M-1 (CV)}. Electrochemical processes of compounds before and after the addition of DNA were found diffusion controlled. Among all compounds, APA-3 exhibited best antitumor activity. © 2013 Elsevier B.V.

Naseer A.,Quaid-i-Azam University | Khan A.Y.,Allama Iqbal Open University
Turkish Journal of Chemistry | Year: 2010

Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to investigate the oxide layer formed on a copper disc electrode and the changes that took place when treated potentiostatically in the range of -0.3 V to 0.9 V in buffer of pH 8.5. The response of an electrode using EIS, initially at equilibrium, to an applied potential was then modeled with equivalent circuits, proposed for different potential regions that completely illustrated the Cu/oxide/electrolyte systems and their properties in terms of 2 interfaces. Criterion for the applicability of equivalent circuit models was discussed. Changes in the film/metal interface as a function of potential were also probed at 30 mHz using Nyquist plots. Diffusion coefficient and concentration of mobile ions in the film calculated from the EIS data came out of the order of 10 -6 cm2 s -1 and 10 -6 mmol mL -1, respectively. © TÜBITAK.

Ghafoor A.,Pakistan National Agricultural Research Center | Sultana T.,The University of Faisalabad | Rizvi Z.F.,Allama Iqbal Open University
Pakistan Journal of Botany | Year: 2012

Thirty seven pure-lines of blackgram were studied for Randomly Amplified Polymorphic DNA (RAPD) markers to investigate diversity. Among 53 primers 36 produced polymorphic fragments in blackgram, hence could be used for investigating genetic diversity. Ninety four markers were observed from 11 primers and out of these 72% were polymorphic. The genotypes acquired from Korea, Afghanistan and AVRDC grouped together, whereas genotypes from Pakistan and India were scattered. The RAPD markers were found useful for studying genetic diversity but clustering did not exhibited indication for agronomic performance, whereas quantitative traits contributed more towards agronomic performance. Cluster revealed that only a portion of genetic diversity has been exploited for blackgram improvement that should broaden involving diverse parents from various clusters.

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