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PublicationArticle Study of ionic conductivity, dielectric characteristics and capacitance measurement of -irradiated conducting polymeric electrolytes(2009) G.K. Prajapati; P.N. GuptaHigh conductivity and high specific capacitance of certain kinds of ion-conducting solid polymer electrolytes has been the subject of intensive study in recent years. These materials play an important role in understanding the polymer characteristics and its technological applications with tremendous impact on several aspects of our life. Extensive studies have been undertaken to investigate ion transport behavior and the effect of γ-irradiation on polymer materials. In this communication, an attempt has been made to study the electrical and dielectric properties including capacitance measurement for pure PVA and PVA-H3PO4 complexed electrolytes under γ-radiation. Various parameters such as conductivity, dielectric constant, dielectric loss, loss tangent and apacitance values have been determined using complex impedance method over the temperature range 303-383 K and frequency domain 10 kHz-1 MHz for different molar ratios of complexed materials. Particular attention and emphasis have been given to the conducting polymers in the capacitance performance of the polymeric system.PublicationArticle Fabrication of white organic light-emitting diodes by co-doping of emissive layer(2009) Ritu Srivastava; Gayatri Chauhan; Kanchan Saxena; S.S. Bawa; P.C. Srivastava; M.N. KamalasananEfficient white light emission by mixing of red emission from (Ir-BTPA) [bis(2-(2′-benzothienyl) pyridinato-N,C3) (acetyl-acetonate) iridium(III) and greenish blue from (FIrPic) [bis(2-(4,6-difluorophenyl) pyridinato-N,C2) iridium(III)] has been studied. Ir-BTPA and FIrPic are co-doped into a 4, 4′ bis 9 carbozyl (biphenyl) (CPB) host. The device emission colour is controlled by varying dopant concentration. Photoluminescence (PL), electroluminescence (EL) and colour coordinates have been studied as a function of applied voltage. The EL spectra of the devices with the co-doped emissive layer show three emission peaks at 469, 500 and 611 nm. Commission Internationale de l'Eclairage (CIE) coordinates of the devices are 0.27, 0.32 at 18 V and are well within the white region.PublicationArticle Synthesis, electronic and IR spectral studies of some polymeric cobalt(II), nickel(II), zinc(II) and cadmium(II) azido complexes with hydrazine(2009) Vinod P. Singh; K.B. Singh; K.K. NarangA series of polymeric cobalt(II), nickel(II), zinc(II) and cadmium(II) azido complexes with hydrazine of the type [M(N2H4)(H 2O)(N3)Cl]n, [M(N2H 4)(N3)2]n and [M(N2H 4)2(N3)2]n have been prepared. These were characterized by elemental analyses, magnetic susceptibility measurements, electronic and IR spectra. The complexes are highly insoluble in polar and non polar solvents. All the complexes decompose with explosion at different temperatures between 100°C to 200°C. The magnetic moment and electronic spectral data for Co(II) and Ni(II) complexes suggest that the complexes have octahedral structure. The ligand-field parameters (10 Dq, B, Β, Β° and LFSE) have also been calculated for all Co(II) and Ni(II) complexes which indicate a significant covalent character of M-L bonds. The IR spectra of the complexes show that the azide group and hydrazine molecule both act as bidentate bridging ligands in [M(N2H 4)(H2O)(N3)Cl]n and [M(N 2H4)(N3)2]n type complexes but the azide group is terminally bonded to metal in all [M(N 2H4)2(N3)2]n type complexes.PublicationArticle Surveillance of corporate governance compliance through a prolific advance(SAGE Publications Ltd, 2009) Twinkle PrustyGlobalization has not only significantly heightened business risks, but has also compelled Indian companies to adopt international norms and good governance. Much has been heard, talked and said about the topic of corporate governance, but unfortunately the parameters to judge its practical implementation is still not very clear to many. It is the premise of apprehension for Indian corporates to initiate hard core action so as to evolve and devour corporate governance at a rapid speed for their survival and growth. Corporate governance is an enduring process that requires integrated efforts and in today's exceedingly specialized epoch, it is indispensable to be the specialist to achieve quality. The question arises that whether the compliance of good corporate governance has evolved and espoused with the changing circumstances of the corporate life and customized to meet those circumstances. This whole exercise calls for professional capability, deliberation, commitment of time and focused awareness with unprejudiced approach. Thus, the surfacing of a growing consensus in regard to the compliance of good corporate governance practices imbibed through appropriate reporting in Indian industries, has been studied to explore the vital dimensions of corporate governance standards for getting pledged to the ideology with the underlying effective analysis, that sets to be a way of life and not mere compliance with a set of rules. This paper presents the evaluation of the compliance of corporate governance on the basis of assigning governance scores to the sample companies as per clause 49 of the listing agreement of SEBI Act. © 2009, SAGE Publications Ltd. All rights reserved.PublicationLetter Colonic conduit for esophageal bypass in Celphos-induced tracheoesophageal fistula: Our experience of two cases(2009) Vivek Srivastava; Mumtaz Ansari; Somprakas Basu; Damayanti Agrawal; T.K. Lahiri; Anand Kumar[No abstract available]PublicationArticle Process parameter optimization for textural properties of ready-to-eat extruded snack food from millet and legume pieces blends(2009) Subir Kumar Chakraborty; Daya S. Singh; B.K. Kumbhar; Dheer SinghFive blends of millets and legume pieces (viz. 12, 16, 20, 24, 28% legume pieces) at varying moisture contents (12, 15, 18, 21, 24%, wet basis [w.b.]) were subjected to extrusion cooking in a single-screw laboratory extruder Brabender DA47055. The extruder was operated at different die head temperatures (160-200C), barrel temperatures (100-140C) and screw speeds (100-140 rpm). Designed experiments were conducted based on central composite rotatable design to determine the optimum processing condition for extruded products. The processing parameters were optimized with the help of response surface methodology to obtain product with maximum crispness and with minimum hardness and cutting strength. The optimum processing conditions obtained were moisture content 24%, w.b.; blend ratio 18.7% legume pieces; die head temperature 171.2C; barrel temperature 140C; and screw speed 103.8 rpm. The corresponding textural properties of the extrudates in terms of crispness, hardness and cutting strength were 50, 48.2 N and 79.7 N, respectively. © 2009, Wiley Periodicals, Inc.PublicationArticle Recombinant YopJ induces apoptosis in murine peritoneal macrophages in vitro : Involvement of mitochondrial death pathway(2009) Ashok Kumar Pandey; Ajit SodhiYersinia species during infection adhere to host immune cells primarily to macrophages and employ its secretary proteins known as Yersinia outer proteins to trigger death in infected cells. In the present study, it is shown that recombinant Yersinia outer protein J (rYopJ) could induce apoptosis in murine peritoneal macrophages in vitro as assessed by morphological features, internucleosomal DNA fragmentation, change in mitochondrial membrane potential (MMP) (Δψm), activation of caspases and Annexin V binding. rYopJ-induced cell death was dose and time dependent. Pre-treatment with broad-spectrum caspase inhibitor Z-VAD-FMK, caspase-3 inhibitor Ac-DEVD-CHO and caspase-8 inhibitor Z-IETD-FMK prevented the change in MMP and DNA fragmentation, suggesting caspase-dependent apoptosis of rYopJ-treated macrophages. Blocking the endocytosis by pre-treatment of cells with cytochalasin B did not prevent the rYopJ-induced macrophages apoptosis. The data further suggest that rYopJ-induced apoptosis is mediated by molecules upstream of caspase-8 and relay through mitochondrial pathway involving Bax, Bcl-2, activation of caspase-8 and caspase-3, Bid and polyadenosine diphosphate-ribose polymerase cleavage, cytochrome c release and DNA fragmentation. The Japanese Society for Immunology. © 2009. All rights reserved.PublicationArticle A β-galactosidase from pea seeds (PsBGAL): purification, stabilization, catalytic energetics, conformational heterogeneity, and its significance(2009) Alka Dwevedi; Arvind M. KayasthaA basic glycosylated β-galactosidase (PsBGAL) has been purified from pea seeds by 910-fold with a specific activity of 77.33 μmol min-1 mg-1 protein. The purified enzyme is an electrophoretically homogeneous protein consisting of a single protein band with an apparent Mr of 55 kDa, while the deglycosylated enzyme has a Mr of 54.2 kDa on SDS-PAGE under reducing conditions. According to MALDI-TOF measurements of the 55 kDa band, the enzyme showed a homology with BGAL from other sources present in the SWISS-PROT database, while it showed no resemblance to any lectin. The N-terminal sequence of PsBGAL was determined as TIECK and showed a resemblance to BGAL from Arabidopsis thaliana (Q93Z24). The enzyme showed an unique property of multiple banding patterns on SDS-PAGE at 20 mA current, with tryptic digests of all bands having similar m/z values (using MALDI-TOF) while it showed only a single band at 10 mA current. PsBGAL is effectively compartmentalized during seed maturation inside vacuoles (pH ∼ 5). The enzyme is capable of hydrolyzing pea seed xyloglucan, and it may be involved in modifying the cell wall architecture during seedling growth and development. The enzyme has a protonated carboxyl group at its active site as observed by ionization constant, thermodynamics, and chemical modification studies. © 2009 American Chemical Society.PublicationArticle Enrichment of sugar content in melon fruits by hydrogen peroxide treatment(2009) Keiko Ozaki; Akio Uchida; Tomoko Takabe; Fumi Shinagawa; Yoshito Tanaka; Teruhiro Takabe; Takahisa Hayashi; Tasuku Hattori; Ashwani K. Rai; Tetsuko TakabeSince sweetness is one of the most important qualities of many fruits, and since sugars are translocated from leaves to fruits, the present study investigates photosynthetic activity, activity of sugar metabolizing enzymes, sugar content in leaves and fruits and endogenous levels of hydrogen peroxide in leaves of melon plants treated with various dilutions of hydrogen peroxide, a nonspecific signaling molecule in abiotic stress. For this purpose, 4-month-old melon plants were treated with various concentrations (<50 mM) of hydrogen peroxide by applying 300 mL per day to the soil of potted plants. The treatments resulted in increased fructose, glucose, sucrose and starch in the leaves and fruits. The most effective concentration of hydrogen peroxide was 20 mM. During the day, soluble sugars in leaves were highest at 12:00 h and starch at 15:00 h. Furthermore, the peroxide treatment increased the photosynthetic activity and the activities of chloroplastic and cytosolic fructose-1,6-bisphosphatase, sucrose phosphate synthase and invertases. Thus, our data show that exogenous hydrogen peroxide, applied to the soil, can increase the soluble sugar content of melon fruits. © 2008 Elsevier GmbH. All rights reserved.PublicationArticle Response of melatonin receptor mt1 in spleen of a tropical indian rodent, funambulus pennanti, to natural solar insolation and different photoperiodic conditions(2009) Sanjukta Lahiri; Chandana HaldarWe analyzed the effect of natural solar insolation and artificial photoperiodic conditions on melatonin MT1 receptor expression of a tropical rodent, Funambulus pennanti. Melatonin mediates reproductive and circadian responses and regulates the production of a large number of cytokines, including interleukin-2 (IL-2), via modulation of MT1 receptor expression. Maximum pineal activity, resulting in high melatonin level, low melatonin receptor expression, and increased splenic mass, was noted in the winter months, while an opposite effect was noted during the summer months. Further, constant light exposure mimicked an "enhanced summer"-like condition with significant hyposplenia, and an opposite effect was observed with constant dark exposure with significant splenomegaly in F. pennanti. In the annual study, a slight increase in melatonin level was noted during the monsoon period, when the duration of photoperiod was the same but the amount of solar insolation and direct radiation decreased. The present study found that not only the duration of natural sunlight (i.e., photoperiod) but the intensity of sunlight expressed by solar insolation affects the circulatory level of melatonin and melatonin receptor expression in this wild tropical rodent. An increase in the circulatory level of melatonin induced a decrease in its receptor subtype MT1 expression in splenic cells, both at the transcriptional and translational levels, thus reflecting autoregulatory down-regulation of melatonin receptors. Therefore, in our animal model, F. pennanti melatonin may be suggested as a molecular messenger of photoperiodic signals (duration and intensity) directly acting via MT1 receptor regulation to adapt the immune system of animals residing in the tropical zone. © 2009 Informa Healthcare USA, Inc.