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Shrivas K.,Guru Ghasidas University | Dewangan K.,Indira Gandhi National Tribal University
Journal of Surfactants and Detergents | Year: 2015

A technique of selective and sensitive surfactant-assisted dispersive liquid-liquid microextraction combined with spectrophotometry was developed for determination of iron in water and food samples. This method involves the formation of a red-colored iron-thiocyanate complex in the presence of cetyltrimethylammonium bromide (CTAB) as cationic surfactant. The use of CTAB assisted in color formation and effective extraction of the complex into the organic solvent through micelle formation prior to spectrophotometric and flame atomic absorption spectrometry measurement. Optimum absorbance and extraction of the iron complex was obtained with concentrations of ammonium thiocyanate, N-phenylbenzimidoyl thiourea, CTAB and sodium chloride of 0.30 M, 3.0 × 10-3 M, 0.40 × 10-3 M and 1.0 %, respectively. The calibration curve was linear over a range of 20-350 ng mL-1 iron with correlation of estimation (R 2) of 0.997. The proposed method was successfully applied to the determination of iron in food (cereal, fruit and vegetable) and water samples. © 2015 AOCS.

Prasad C.P.,Skåne University Hospital | Chaurasiya S.K.,Skåne University Hospital | Chaurasiya S.K.,Indira Gandhi National Tribal University | Axelsson L.,Skåne University Hospital | Andersson T.,Skåne University Hospital
Molecular Oncology | Year: 2013

An important role for WNT-5A is implicated in a variety of tumors, including breast carcinoma. We previously showed that WNT-5A signaling inhibits migration and metastasis of breast cancer cells, and that patients with primary breast cancer in which WNT-5A was expressed have a better prognosis. Despite the fact that RhoGTPase Cdc42 is commonly associated with increased cell migration, we here show that recombinant WNT-5A activates the Cdc42 in breast cancer cells (lines MDA-MB468 and MDA-MB231) in a time-dependent manner. Activation of Cdc42 was also observed in MDA-MB468 cells that were stably transfected with a WNT-5A plasmid (MDA-MB468-5A). In all situations, increased Cdc42 activity was accompanied by decreased migration and invasion of the breast cancer cells. To explore these findings further we also investigated the effect of WNT-5A signaling on ERK1/2 activity. Apart from an initial Ca2+-dependent rWNT-5A-induced activation of ERK1/2, Cdc42 activity was inversely correlated with ERK1/2 activity in both rWNT-5A-stimulated parental MDA-MB468 and MDA-MB468-5A cells. We also demonstrated increased ERK1/2 activity in MDA-MB468-5A cells following siRNA knockdown of Cdc42. Consistent with these results, breast cancer cells transfected with constitutively active Cdc42 exhibited reduced ERK1/2 activity, migration and invasion, whereas cells transfected with dominant negative Cdc42 had increased ERK1/2 activity in response to rWNT-5A. To gain information on how ERK1/2 can mediate its effect on breast cancer cell migration and invasion, we next investigated and demonstrated that WNT-5A signaling and constitutively active Cdc42 both decreased matrix metalloproteinase 9 (MMP9) activity. These data indicate an essential role of Cdc42 and ERK1/2 signaling and MMP9 activity in WNT-5A-impaired breast cancer cells. © 2013 Federation of European Biochemical Societies.

Chaturvedi R.,Indira Gandhi National Tribal University | Mishra S.D.,Banaras Hindu University
Transactions of the Institute of Indian Geographers | Year: 2015

The paper using satellite imagery and GIS attempts to associate geomorphology in defining flood susceptibility zones in Allahabad district, Uttar Pradesh, India. Varied landforms found in the district are the result of the processes of erosion and deposition that were operated in the past and are still continuing. Flood plain and associated features in the northern part of the district got formed during the Quaternary period whereas numerous landform features in the southern part were defined by the development of Vindhyan plateau during Pre-Cambrian to Recent periods.

Shukla P.N.,Banaras Hindu University | Pandey K.D.,Banaras Hindu University | Mishra V.K.,Banaras Hindu University | Mishra V.K.,Indira Gandhi National Tribal University
Critical Reviews in Environmental Science and Technology | Year: 2013

Methane (CH4) is one of the strongest greenhouse gases. Sources of CH4 are anthropogenic and natural, former playing ∼60% role. Major sink for CH4 are the atmospheric OH and Cl radicals (originating from CFCs), and biological system. Biological CH4 sink is mediated through the CH4 oxidation by the specialized group of bacteria called methanotrophs (MB). Methanotrophs have been reported from almost all the soil systems such as sediments, oceans, extremes of pH, salinity, and temperature. They oxidize methane aerobically in the presence of the enzyme methane monooxygenase (MMO). Anaerobic methane oxidation (AOM) also occurs in marine ecosystem where sulfate is final electron acceptor. Methanotrophs are of two types, first is cultured and low affinity group while the second is uncultured and high affinity group. Most of them can be grouped as Type I and Type II belonging to γ-and α-Proteobacteria, respectively. They may constitute up to 2% of total bacterial population in soil depending on physical factors such as water, temperature, soil depth, pH, texture, gaseous atmosphere (methane, oxygen, and CO2), soil organic content, and biological factors such as vegetation and microbial consortia. Besides, anthropogenic factors such as fertilizers, agro-and organochemicals, and land use pattern have strong influence over them. Global climate change including acid rain, high temperature, increasing rainfall, and drought have potential to affect the global methane sink activity. The authors attempt to review the recent advances made regarding CH4 oxidation and methanotrophic population size as well as community structure as affected by the various natural and anthropogenic factors. © 2013 Taylor and Francis Group, LLC.

Sharma N.K.,Indira Gandhi National Tribal University
Biodiversity and Conservation | Year: 2015

Human activities have long been recognized as a major force shaping the biosphere. Advancing urbanization is one such transformation with unforeseen effect on the soil microbiota, including the cyanobacteria. This includes the loss of agronomically important nitrogen fixing cyanobacteria, which may negatively affect the agricultural productivity of peri-urban soils. However, empirical studies are lacking to validate the statement. Even, in journals specifically dealing with diversity and distribution of organisms, urban ecology and ecosystems. Here, I describe a critical area beset with challenges that needs to be investigated. © 2015, Springer Science+Business Media Dordrecht.

Paramanik V.,Banaras Hindu University | Thakur M.K.,Banaras Hindu University | Thakur M.K.,Indira Gandhi National Tribal University
Archives Italiennes de Biologie | Year: 2013

During aging, brain undergoes several changes which influence its function through alteration in the expression of genes. Some of these genes are regulated by estrogen which requires a host of coregulator proteins including CREB. In brain, CREB is expressed in different regions and regulates a wide range of functions such as cellular growth, proliferation and memory in response to a variety of intracellular signaling events including synaptic efficacy and long-lasting changes in synaptic plasticity. In response to signals at the cell surface, CREB is phosphorylated in the nucleus by various protein kinases via secondary messengers such as cAMP and/or Ca+2 for regulating specific genes. Alterations in CREB signaling lead to cognitive deficits as observed in normal aging and neurodegenerative diseases. In brain, the expression of CREB changes with age, but its variation with sex is not known. So, in this review paper, we summarize recent findings indicating age and sex dependent expression of CREB and its interaction with estrogen receptor (ER)β, and the role of CREB signaling in brain aging and diseases. Such understanding of CREB signaling through ER may help to design therapeutic strategies for age related cognitive deficits and neurodegenerative disorders.

Das R.,CSIR - National Chemical Laboratory | Jaiswal A.,Indira Gandhi National Tribal University | Poddar P.,CSIR - National Chemical Laboratory
Journal of Physics D: Applied Physics | Year: 2013

Single-phase orthorhombic DyMnO3 and GdMnO3 nanoparticles in the size range 60-70 and 35-45 nm, respectively, were synthesized using a modified hydrothermal method. The magnetic property measurements of DyMnO3 nanocrystals show anomalies around ∼43 K (antiferromagnetic (AFM) coupling between Mn3+ spins) and at 7 K in the form of a peak in the zero-field-cooled curve (AFM coupling between Dy 3+ spins). Whereas, GdMnO3 undergoes a phase transition at ∼42 K from paramagnetic to an incommensurate-antiferromagnetic phase (ICAFM) followed by a second anomaly at ∼22 K, which could be associated with the transition from ICAFM into a canted A-type AFM ordering of the Mn 3+ spins. This transition is followed by a long-range ordering of the Gd3+ moments at 6 K yielding the canting of the Gd3+ spins with a ferromagnetic (FM) component antiparallel to the FM moment of the canted Mn3+ spins. No anomaly near the Néel temperature of the Mn moments for both DyMnO3 and GdMnO3 nanoparticles was observed in ac magnetization which were observed in dc magnetization. The room temperature Raman spectra of DyMnO3 shows two most intense Raman modes at 480 and 609 cm-1 which can be assigned to an antisymmetric Jahn-Teller stretching mode and a symmetric or breathing stretching mode, respectively, involving Mn-O bond stretching. © 2013 IOP Publishing Ltd.

Thakur T.K.,Indira Gandhi National Tribal University
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2014

The purpose of this study was to characterize the carbon, nitrogen, phosphorus and potassium in the Barnowpara Sanctuary, Raipur district, Chhattisgarh, India through the use of satellite remote sensing and GIS The total storage of nutrients in vegetation (OS+US+GS) varied from 105.1 to 560.69 kg ha-1 in N, 4.09 kg ha-1 to 49.59 kg ha-1 in P, 24.59 kg ha-1 to 255.58 kg ha-1for K and 7310 to 4836 kg ha-1 for C in different forest types. They were highest in Dense mixed forest and lowest in Degraded mixed forest. The study also showed that NDVI and carbon storage was strongly correlated to Shannon Index and species richness thus it indicates that the diversity of forest type play a vital role in carbon accumulation. The study also developed reliable regression model for the estimation of LAI, biomass, NPP, C & N storage in dry tropical forests by using NDVI and different vegetation indices, which can be derived from fine resolution satellite data. The study shows that dry tropical forests of Central India are quite immature and not in standing state and have strong potential for carbon sequestration. Both quantitative and qualitative information derived in the study helped in evolving key strategies for maintaining existing C pools and also improving the C sequestration in different forest types. The study explores the scope and potential of dry tropical forests for improving C sequestration and mitigating the global warming and climatic change.

Patel S.K.S.,Indian Institute of Technology Kanpur | Dewangan K.,Indira Gandhi National Tribal University | Srivastav S.K.,Indian Institute of Technology Kanpur | Gajbhiye N.S.,Indian Institute of Technology Kanpur
Current Applied Physics | Year: 2014

Monodisperse indium oxide (In2O3) nanoparticles (NPs) with the average diameter of 11 nm were prepared by a solvothermal method. The In2O3 NPs were characterized by X-ray diffraction, Raman and transmission electron microscopy. The intrinsic nature of ferromagnetism in In2O3 NPs has been established with the experimental observation of magnetic hysteresis loop. Photoluminescence and UV-visible studies were employed to evidence the presence of oxygen vacancies and revealed that the oxygen vacancies contribute to the ferromagnetism. The origin of ferromagnetism in In2O3 NPs may be due to exchange interactions among localized electron spin moments resulting from oxygen vacancies. © 2014 Elsevier B.V. All rights reserved.

Singh P.,Indira Gandhi National Tribal University
Sensors and Actuators, B: Chemical | Year: 2016

SPR is a real-time, label-free measurement of binding kinetics and affinity. Success of SPR biosensor is evident by the growing number of commercially available instruments. In the current review, development in plasmon resonance techniques such as SPR, SPR-imaging (microscope, spectroscope, Electrochemical Impedance), nanoplasmonics and microfluidics, membrane proteins: receptor studies, sensors based on polarization and interferometery, PWR, SPR-MS, Signal locked SPR, FOPPR, Mid-IR SPR, trends in protein array technology and point-of-care (POC) testing over last decade are summarized. In addition, advancement over sensor configuration, mechanism and immobilization techniques are also discussed. Advantage and disadvantage of each methodology is provided along with some of the latest accomplishments. © 2016 Elsevier B.V. All rights reserved.

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