University of CalcuttaWest Bengal

of Botany, India

University of CalcuttaWest Bengal

of Botany, India
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Fartyal R.S.,Systematics Cytogenetics and Molecular Laboratory | Sati P.C.,Systematics Cytogenetics and Molecular Laboratory | Pradhan S.,P.A. College | Pradhan S.,University of CalcuttaWest Bengal | And 5 more authors.
ZooKeys | Year: 2017

All Indian species of the genus Lordiphosa Basden are reviewed, with descriptions of four new species, L. curva Fartyal & Toda, sp. n. of the denticeps species group and L. ayarpathaensis Kandpal & Singh, sp. n., L. makaibarensis Pradhan & Chatterjee, sp. n. and L. srinagarensis Sati & Fartyal, sp. n. of the nigricolor species group. Two of the new species, L. ayarpathaensis and L. makaibarensis, were found visiting flowers of Hedychium spicatum and Datura suaveolens, respectively. This is the first record of flower visitation in Lordiphosa flies. In addition, L. parantillaria (Kumar & Gupta, 1990), syn. n. is synonymized with L. antillaria (Okada, 1984). Supplementary and revised descriptions for L. antillaria and L. neokurokawai (Singh & Gupta, 1981) and a key to all Indian species of Lordiphosa are provided. © 2017, Pensoft Publishers. All rights reserved.

Das S.,University of CalcuttaWest Bengal | Gupta R.,University of CalcuttaWest Bengal
Computational Science and Engineering - Proceedings of the International Conference on Computational Science and Engineering, ICCSE2016 | Year: 2017

Electrocardiography (ECG) is the most popular noninvasive technique for primary stage investigation on cardiac functions. ECG data compression finds wide application in patient monitoring and heart rhythm analysis. In this paper, we present an efficient compression method for single lead Electrocardiogram (ECG) signals based on the Discrete Wavelet Transform (DWT). Since the ECG consecutive beats exhibit sufficient redundant information, DWT was applied on an average beat estimate, computed over 10 beats and the residuals of the corresponding original beats. Selections of the significant coefficients from the average beat as well as the residuals were based on Energy Packing Efficiency (EPE). Finally, the selected coefficients for the average beat were quantized at 8-bit, and the residuals with 5-bit and compressed by a delta coder. The significance maps were encoded by binary coder and run length encoder. The algorithm was validated with one min. mitdb data under Physionet at 360 Hz sampling to obtain an average Compression Ratio (CR) of 8.65, PRD of 2.32, PRDN of 4.30. The reconstructed signals were clinically validated by cardiologists. © 2017 Taylor & Francis Group.

Sil S.,University of Calcutta | Ghosh R.,University of Calcutta | Sanyal M.,University of Calcutta | Guha D.,University of CalcuttaWest Bengal | Ghosh T.,University of Calcutta
Journal of Immunotoxicology | Year: 2016

Colchicine induces neurodegeneration, but the extent of neurodegeneration in different areas of the brain in relation to neuroinflammation remains unclear. Such information may be useful to allow for the development of a model to compare colchicine-induced neurodegeneration with other neurodegenerative diseases such as Alzheimers Disease (AD). The present study was designed to investigate the extent of neurodegeneration along with neuroinflammation in different areas of the brain, e.g. frontal cortex, parietal cortex, occipital cortex, corpus striatum, amygdala and hippocampus, in rats along with memory impairment 21 days after a single intracerebroventricular (icv) injection of colchicine. Memory parameters were measured before and after icv colchicine injection in all test groups of rats (control, sham-operated, colchicine-injected [ICIR] rats). On Day 21 post-injection, rats from all groups were anesthesized and tissues from the various brain areas were collected for assessment of biomarkers of neuroinflammation (i.e. levels of ROS, nitrite and proinflammatory cytokines TNFα and IL-1β) and neurodegeneration (assessed histologically). The single injection of colchicine resulted in impaired memory and neurodegeneration (significant presence of plaques, Nissl granule chromatolysis) in various brain areas (frontal cortex, amygdala, parietal cortex, corpus striatum), with maximum severity in the hippocampus. While IL-1β, TNFα, ROS and nitrite levels were altered in different brain areas in the ICIR rats, these parameters had their greatest change in the hippocampus. This study showed that icv injection of colchicine caused strong neurodegeneration and neuroinflammation in the hippocampus of rats and the increases in neurodegeneration were corroborated with those of neuroinflammation at the site. The present study also showed that the extent of neurodegeneration and neuroinflammation in different brain areas of the colchicine-injected rats were AD-like and supported the fact that such rats might have the ability to serve as a sporadic model of AD. © 2015 Informa UK Limited trading as Taylor & Francis Group.

Sur A.,University of CalcuttaWest Bengal | Kanoria M.,University of Calcutta
Mathematics and Mechanics of Solids | Year: 2017

The aim of the present contribution is concerned with the interactions of thermoelastic displacements, temperatures and stresses for the three-phase-lag and Green-Naghdi heat equations in a functionally graded transversely isotropic plate subjected to a spatially varying heat source. The upper surface of the plate is stress free with prescribed surface temperature while the lower surface of the plate rests on a rigid foundation and is thermally insulated. The governing equations for displacement and temperature fields are obtained in the Laplace-Fourier transform domain by applying Laplace and Fourier transform techniques. The inversion of double transform has been done numerically. The numerical inversion of Laplace transform is done by using a method based on the Fourier Series expansion technique. The solution to the analogous problem for isotropic material is obtained by taking suitable nonhomogeneity parameters. A comparative study between isotropic material and transversely isotropic material is also shown. In absence of nonhomogeneity, the results corresponding to Green-Naghdi II, Green-Naghdi III and 3P lag models agree with the results of the existing literature. © The Author(s) 2015.

Chakraborty S.B.,University of Kaposvár | Chakraborty S.B.,University of CalcuttaWest Bengal | Molnar T.,University of Kaposvár | Ardo L.,Research Institute for Fisheries | And 2 more authors.
Turkish Journal of Fisheries and Aquatic Sciences | Year: 2015

The effects of the isoflavone genistein and methanol extract of Basella alba leaves were evaluated in Nile tilapia, Oreochromis niloticus on growth and immunostimulation. Adult tilapia (mean weight 39.55 g) was fed diets containing genistein (1 gm/kg) and methanol extract of B. alba (1 g/kg) for 35 days. Basella alba extract treated tilapia showed significantly higher (P<0.05) weight gain, respiratory burst, phagocytic activity, plasma protein content and plasma lysozyme activity compared to fish fed control diet. The B. alba extract treated fish showed the highest final individual mean body weight, final individual length, specific growth rate, hepatosomatic index and total immunoglobulin content. The phagocytic and respiratory burst activities of genistein treated fish were significantly higher (P <0.05) compared to the control group. The weight gain, lysozyme activity and total protein content of genistein treated fish did not differ significantly (P>0.05) from both control and B. alba treated fish. There was no significant difference (P > 0.05) in the food conversion ratio as well among the different treatment groups. The study indicates that B. alba methanol extract might positively influence the growth and protect the health status of tilapia. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.

Mallick S.,West Bengal State University | Dutta A.,West Bengal State University | Chaudhuri A.,West Bengal State University | Mukherjee D.,National Center for Cell Science | And 17 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2016

In our previous report, we showed that astrakurkurone, a triterpene isolated from the Indian mushroom Astraeus hygrometricus (Pers.) Morgan, induced reactive oxygen species, leading to apoptosis in Leishmania donovani promastigotes, and also was effective in inhibiting intracellular amastigotes at the 50% inhibitory concentration of 2.5 μg/ml. The aim of the present study is to characterize the associated immunomodulatory potentials and cellular activation provided by astrakurkurone, leading to effective antileishmanial activity in vitro and in vivo. Astrakurkurone-mediated antileishmanial activity was evaluated by real-time PCR and flow cytometry. The involvement of Toll-like receptor 9 (TLR9) was studied by in vitro assay in the presence of a TLR9 agonist and antagonist and by in silico modeling of a three-dimensional structure of the ectodomain of TLR9 and its interaction with astrakurkurone. Astrakurkurone caused a significant increase in TLR9 expression of L. donovani-infected macrophages along with the activation of proinflammatory responses. The involvement of TLR9 in astrakurkurone-mediated amastigote killing has been evidenced from the fact that a TLR9 agonist (CpG, ODN 1826) in combination with astrakurkurone enhanced the amastigote killing, while a TLR9 antagonist (bafilomycin A1) alone or in combination with astrakurkurone curbed the amastigote killing, which could be further justified by in silico evidence of docking between mouse TLR9 and astrakurkurone. Astrakurkurone was found to reduce the parasite burden in vivo by inducing protective cytokines, gamma interferon and interleukin 17. Moreover, astrakurkurone was nontoxic toward peripheral blood mononuclear cells of immunocompromised patients with visceral leishmaniasis. Astrakurkurone, a nontoxic antileishmanial, enhances the immune efficiency of host cells, leading to parasite clearance in vitro and in vivo. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Mukhopadhyay A.,University of CalcuttaWest Bengal | Bhattacharyya T.,University of CalcuttaWest Bengal | Dasgupta A.K.,University of CalcuttaWest Bengal | Chakrabarti K.,University of CalcuttaWest Bengal
Journal of Molecular Catalysis B: Enzymatic | Year: 2015

An immobilization technique (using nanotechnology) that imparts psychrostability and enhanced activity to a psychrophilic pectate lyase (PL) has been described here. Pectate lyase from a pyscrophile was supplemented with calcium hydroxyapatite nanoparticles (NP-PL) as a substitute for Ca, (the cationic activator of this enzyme) and entrapped in single walled nanotube (SWNT) based molecular self-assembly. The activity and stability of PL was enhanced both at temperatures as low as 4°C and as high as 80°C in presence of NP and SWNT. The enzyme could be repeatedly released and re-trapped (in SWNT based molecular self-assembly) while retaining significant activity. The immobilized PL (in SWNT based molecular self-assembly), retained its activity after repeated freezing and thawing. This unique capability of SWNT to activate and stabilize a cold active enzyme at temperatures much lower or higher than its optimal range may be utilized for processes that require bio-conversion at low temperatures while simultaneously allowing for shifts to higher temperature. © 2015 Elsevier B.V.

Ghosh S.,University of CalcuttaWest Bengal | Ram S.S.,University of CalcuttaWest Bengal | Ram S.S.,UGC-DAE Consortium for Scientific Research | Ram S.S.,Institute of PhysicsBhubaneswar | And 4 more authors.
Marine Pollution Bulletin | Year: 2016

Hooghly Estuary along with the Sunderban mangroves forms one of the most diverse ecosystems in the world. We investigated the vertical and horizontal distribution of elements at nine sampling locations in this estuary for assessing the degree of elemental contamination. The elemental concentrations were analyzed by an Energy Dispersive X-ray Flurosence spectrometer (EDXRF). A higher enrichment factor (EF) value of trace elements (V, Cr, Mn, Fe, Ni, Cu and Zn) is evident considering all the sampling locations. Geo-accumulation index (Igeo) values of all the sampling locations and core depth reveals Cr and Cu are under Igeo Class I level of contamination. The value of the pollution load index (PLI) varies between 0.94–1.65 with maximum at Chemaguri and minimum at Haldi Estuary and Petuaghat. The overall variation in elemental concentration may be due to differential discharge pattern of storm water and agricultural run-off, industrial effluent and domestic sewage. © 2016 Elsevier Ltd

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