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Karthiga R.K.J.,Thiagarajar College of Engineering | Ravikumar R.,Lady Doak College
Journal of Child Sexual Abuse | Year: 2014

This article attempts to explore the cultural and patriarchal relevance of child sexual abuse in a conservative town in India, with a special interest in understanding the current problems experienced by teenage girls in India. A questionnaire was distributed to 100 respondents who belonged to Thiagarajar College of Engineering, Thiruparangundram, Madurai. The questionnaire was developed with special reference to the female protagonist, Lily in Jaishree Misras Secrets and Lies. The resulting article also includes an e-interview with Jaishree Misra. The researchers hypothesize that change can be envisioned when the social conscience is awakened to cruel events that happen in the Indian population. Change regarding social events must go even further to allow children to blossom and experience the joys of childhood. © Taylor & Francis Group, LLC.

Nidya M.,Lady Doak College | Umadevi M.,Mother Teresa Women's University | Rajkumar B.J.M.,Lady Doak College
Journal of Experimental Nanoscience | Year: 2015

Silver nanoparticles (NPs) functionalised with L-histidine is synthesised by a chemical reduction approach using two different methods of stirring – using a magnetic stirrer and an ultrasonicator. The former method exhibits a strong narrow absorption peak at 396 nm and the latter a blue-shifted weak broad plasmon band for the bare silver NPs. When the capping agent is incorporated, a single broad peak at low intensity evolves for the first method of stirring whereas two distinct peaks are noticed for the second. The Transmission Electron Microscope (TEM) results confirm the spherical shape of the silver NPs in the first case. In the second case, both spherical and elliptical particles are obtained. Zeta potential measurements further confirm the stability of the histidine-capped silver NPs in comparison with the pure silver NPs. A study of the variation of the plasmon peak with pH indicates that a basic medium favours the growth of the histidine-capped silver NPs. A surface-enhanced Raman scattering investigation confirms the adsorption of the capping molecule through the nitrogen of the imidazole ring with the carboxylate group pointing outwards. L-histidine-capped silver NPs can find application in biosensors and biomedicine, particularly when prepared by the magnetic stirrer method due to its greater stability. © 2013, © 2013 Taylor & Francis.

Rajkumar B.J.M.,Lady Doak College
Molecular Physics | Year: 2015

Adsorption of anthracene on silver is investigated based on the density functional theory and the surface-enhanced Raman spectroscopy (SERS). Variations in bond and dihedral angles of the optimised geometry of anthracene indicate distortions in the hexagonal structure of the ring nearer to the silver cluster and deviations in the co-planarity of carbon atoms. Natural bond orbital analysis confirms intramolecular charge transfers from π(C–C) to π*(C–C) and π(C–C) to σ*(Ag–Ag) orbitals. Higher polarisation resulting from charge transfers on adsorption accounts for Raman enhancements of selective vibrational modes and band shifts. Surface plasmon resonance peak of silver nanoparticles after the adsorption of anthracene observed around 399 nm compares well with the theoretically simulated UV–vis spectrum derived using the time-dependent density functional theory. Theoretical and experimental SERS correlate well, confirming the process of adsorption, the tilted orientation of anthracene on the silver surface and the adsorption mechanism reported. Localisation of the electron density together with a reduced band gap after the adsorption on silver suggests its utility in the design of electro-active organic molecular devices. © 2015 Taylor & Francis

Kavitha A.L.,Alagappa University | Gurumallesh Prabu H.,Alagappa University | Ananda Babu S.,Alagappa University | Suja S.K.,Lady Doak College
Journal of Nanoscience and Nanotechnology | Year: 2013

This work was aimed to develop reusable magnetite chitosan composite containing carbon paste electrode for biosensor application. Glucose oxidase (GOx) enzyme was used to prepare GOx-magnetite-chitosan nanocomposite containing carbon paste electrode for sensitive detection of glucose. The immobilized enzyme retained its bioactivity, exhibited a surface confined reversible electron transfer reaction, and had good stability. The surface parameters like surface coverage (τ), Diffusion coefficient (D0), and rate constant (kS) were studied. The carbon paste modified electrode virtually eliminated the interference during the detection of glucose. The excellent performance of the biosensor is attributed to large surface-to-volume ratio, high conductivity and good biocompatibility of chitosan, which enhances the enzyme absorption and promotes electron transfer between redox enzymes and the surface of electrode. The shelf life of the developed electrode system is about 12 weeks under refrigerated conditions. We report for the first time in the fabrication of carbon paste bioelectrode containing magnetite-chitosan-GOx. Copyright © 2013 American Scientific Publishers All rights reserved.

Rekha T.N.,Lady Doak College | Rajkumar B.J.M.,Lady Doak College
Canadian Journal of Physics | Year: 2015

We systematically investigate growth patterns of small silver clusters, Agn (n ≤ 10), using density functional theory (DFT) and time-dependent density functional theory (TDDFT), considering Ag2, Ag3, and Ag3 as basic building units. Nearest-neighbor distances increase gradually with increasing n. Compared with an earlier study, where the clusters were developed by adding one atom at a time, the clusters derived in this investigation had considerably higher computed binding energies, confirming increased stability and suggesting possible growth patterns using these basic units. We used TDDFT methods to simulate the ultraviolet-visible spectra of the silver clusters, which are in good agreement with the reported experimental absorption spectrum of Ag nanoparticles. Our study indicates that the clusters formed with units of Ag3 tend to form more reactive clusters, particularly if an odd number of atoms is involved. Further, the higher level of computations employed gives better insight into the process of particle growth. The disproportionation energies of clusters built using this scheme are compared with those built one atom at a time. Mulliken population analysis of the distributions indicates the presence of polarities among the atoms in some of the cluster isomers, suggesting sites of increased activity. In addition, patterns established for the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), and HOMO-LUMO energy gaps may be used to model stable clusters with modified optoelectrical properties. © 2015 Published by NRC Research Press.

Mahalakshmi A.,Lady Doak College | Shenbagarathai R.,Lady Doak College
Journal of Biomolecular Structure and Dynamics | Year: 2010

A three dimensional model was developed for Cry10Aa protein sequence of B. thuringiensis LDC-9 and B. thuringiensis israelensis that has not been solved empirically by X-ray crystallography or NMR. Homology modeling was employed for the structure prediction using Cry2Aa as template protein, a high-resolution X-ray crystallography structure. The model predicted for the B. thuringiensis LDC-9 Cry10Aa protein reveals a partial N-terminal domain only due to its partial sequence of 104 amino acids. B. thuringiensis israelensis Cry10Aa model contains three domains such as domain I, a bundle of eight α helices with the central relatively hydrophobic helix surrounded by amphipathic helices while domain II and III contain mostly β-sheets. Significant structural differences within domain II in this model among all Cry protein structures indicates that it is involved in recognition and binding to cell surfaces. Comparison of B. thuringiensis israelensis predicted structure with available experimentally determined Cry structures reveals identical folds. The distribution of electrostatic potential on the surface of the molecules in the model is non-uniform and identifies one side of the α-helical domain as negatively charged indicating orientation of toxic molecules toward the cell membrane during the initial binding with a cell surface receptor. The collective knowledge of Cry toxin structures will lead to a more critical understanding of the structural basis for receptor binding and pore formation, as well as allowing the scope of diversity to be better appreciated. This model will serve as a starting point for the design of mutagenesis experiments aimed to improve the toxicity and to provide a new tool for the elucidation of the mechanism of action of these mosquitocidal proteins. ©Adenine Press (2010).

Type 1 diabetes mellitus formerly called juvenile diabetes, is an organ specific T-cell mediated autoimmune disease characterized by the progressive loss of function of the insulin producing beta-cells of the islets of Langerhans. Cytotoxic T lymphocyte-associated antigen 4 gene (CTLA-4) has been proposed as a candidate gene for conferring susceptibility to autoimmunity. Association of CTLA-4 gene polymorphism is well established in autoimmune endocrinopathies across world population. The present study was conducted to investigate the association of CTLA-4 exon 1 49A/G polymorphism with TIDM in Madurai, a city in Southern India. Fifty three clinically proven T1DM patients and 53 control subjects with no history of autoimmune disease were recruited for the study. Genomic DNA was extracted from peripheral blood. CTLA-4 exon 1 49 A/G polymorphism was assessed using PCR-RFLP methods. Our findings revealed a significant association of CTLA-4 exon 1 49 A/G polymorphism with T1DM in Madurai population.

Balasubramanian R.,Lady Doak College | Michael R.D.,Tamil University
Aquaculture Research | Year: 2016

N-Oxide-Quaternary Alkaloid Fraction (NOQAF) of a Chlorophycean macroalga, Caulerpa scalpelliformis (R.Br.) C. Ag f. denticulata (Deaisne) Weber van Bosse (Patent filed) was intraperitoneally administered at different doses (0, 2, 20 or 200 mg kg-1 body weight) in different groups of Channa striata to assess its effect on the non-specific immune responses and disease resistance against live virulent Aeromonas hydrophila. A reference positive control [MacroGard (Biotec Pharmacon ASA, Norway) 20 mg kg-1 body weight] was simultaneously maintained to compare its efficacy. The fraction (NOQAF) has been found to enhance the serum lysozyme, peroxidase, antiprotease and alternate complement activities and the reactive oxygen and nitrogen species production and peroxidase activity by the peripheral blood leucocytes than the control group during the study period. On experimental challenge with live virulent A. hydrophila, maximum RPS values of 88.8 and 87.4 were noted in the groups treated with single dose of 20 mg kg-1 and double dose of 2 mg kg-1 of NOQAF respectively. In conclusion, the intraperitoneal administration of the N-Oxide-Quaternary Alkaloid Fraction (NOQAF) of C. scalpelliformis has been found to significantly enhance the non-specific immune responses and disease resistance against A. hydrophila in Channa striata. © 2016 John Wiley & Sons Ltd.

Jayanthi Kalaivani G.,Lady Doak College | Suja S.K.,Lady Doak College
Carbohydrate Polymers | Year: 2016

Inulin, a water soluble carbohydrate polymer, was extracted from Allium sativum L. by hot water diffusion method. A novel bio-nanocomposite was prepared by embedding TiO2 (rutile) onto the inulin matrix. The extracted inulin and the prepared bio-nanocomposite were characterized using UV-vis, FT-IR, XRD, SEM, TEM and TGA techniques. The photocatalytic activity of the bio-nanocomposite for the degradation of methylene blue was studied under UV illumination in batch mode experiment and was found to be twice as high as that of pristine TiO2. The kapp for inulin-TiO2 (0.0449 min-1) was higher than that for TiO2 (0.0325 min-1) which may be due to the synergistic action of inulin and TiO2. The stabilization of photo excited electron suppressed the electron-hole pair recombination thereby inducing the electrons and the holes to participate in the photo reduction and oxidation processes, respectively and enhancing the photocatalytic activity. © 2016 Elsevier Ltd. All rights reserved.

Angeline T.,Lady Doak College | Isabel W.,Lady Doak College | Tsongalis G.J.,Dartmouth Hitchcock Medical Center
Experimental and Molecular Pathology | Year: 2010

Nitric oxide (NO) synthesized by vascular endothelial cells, is a vasodilator agent produced from endothelial NO synthase (eNOS). It has been reported that decreased bioavailability of NO plays an important role in the development and progression of atherosclerosis.Electrocardiographically proven 100 patients with acute myocardial infarction and 100 age and sex matched healthy individuals with normal coronary arteries were included for the study. The genotypes of a 27-bp insertion/deletion in intron 4 (eNOS 4b/4a) and G894T polymorphism in exon 7, were determined by PCR analysis based on the banding pattern on gel electrophoresis. The genotype frequencies were calculated following the Hardy-Weinberg law. Serum NO level was also estimated by the Griess method. NO levels in AMI patients were higher than those of the healthy subjects (median [interquartile range], (14.36[12.42-15.78]) μM compared with 11.28[10.32-11.89]) μM; p < 0.001; Mann-Whitney rank sum test, U=285. Mutant "T" allele frequency of the eNOS-G894T polymorphism was found to be comparatively higher (0.29) in AMI patients than among the controls (0.17). The calculated Odds ratio showed that the occurrence of mutant allele "T" was 1.6 fold as frequent in cases than controls [OR. =1.6 (95%CI 0.898 to 2.833)].To conclude, in the present study, (i) NO levels were found to be increased in patients than in controls, (ii) the homozygous mutant (TT) genotype confers genetic susceptibility to coronary artery disease (iii) both the eNOS 4a/b and G894T polymorphisms were not associated with serum NO levels in a South Indian Tamil population. © 2010 Elsevier Inc.

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