Sree Chaitanya College

North Guwāhāti, India

Sree Chaitanya College

North Guwāhāti, India
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Gayen K.S.,University of Calcutta | Sengupta T.,University of Calcutta | Saima Y.,University of Calcutta | Das A.,University of Calcutta | And 2 more authors.
Green Chemistry | Year: 2012

Small Cu(0)-nanoparticles (NPs) are fabricated utilizing CuSO 4·5H2O, surfactant (SDS) and ascorbic acid in aqueous medium. Its outstanding catalytic activity under low catalyst loading is developed toward reductive cleavage of isoxazoline, carbonyl azide and domino cyclization to furnish valuable 2-hydroxy-4-keto esters, primary amides and a new class of heterocycle, 4-hydroxy-2-pyrroline-5-one. This journal is © The Royal Society of Chemistry.


Dalapati S.,University of Calcutta | Alam M.A.,Aliah University | Jana S.,University of Calcutta | Karmakar S.,Sree Chaitanya College | Guchhait N.,University of Calcutta
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Test paper coated with Schiff base [(N,N/-bis(5-nitro- salicylidene)hydrazine] receptor 1 (host) can selectively detect fluoride and acetate ions (guest) by developing yellow color which can be detected by naked-eye both in aqueous-acetonitrile solution and in solid supported test kit. UV-vis spectral analysis shows that the absorption peaks at 288 and 345 nm of receptor 1 gradually decrease its initial intensity and new red shifted absorption bands at 397 nm and 455 nm gradually appear upon addition of increasing amount of F- and AcO- ions over several tested anions such as H2PO4-, Cl-, Br-, I-, NO3-, NO2-, HSO4-, HSO3-, and ClO4- in aqueous-acetonitrile solvent. The colorimetric test results and UV-vis spectral analysis are in well agreement with 1H NMR titration results in d6-DMSO solvent. The receptor 1 forms 1:2 stable complexes with F- and AcO- ions. However, similar kind of observation obtained from UV-vis titrations in presence of AcOH corresponds to 1:1 complexation ratio indicating the formation of H-bonding interaction between the receptor and anions (F- and AcO- ions). So, the observed 1:2 complexation ratio can only be explained on the basis of deprotonation (∼1 eqv.) and H-bonding (∼1 eqv.) interactions [1]. The ratiometric analysis of host-guest complexes corroborates well with the proposed theoretical model optimization at Density Functional Theory (DFT) level. © 2012 Elsevier B.V. All rights reserved.


Panigrahi D.,Sree Chaitanya College | Panigrahi D.,Jadavpur University
AIP Conference Proceedings | Year: 2010

We discuss the quintessential phenomena in higher dimensional spacetime with the help of a Chaplygin type of matter field. The dimensional reduction is possible in this case. It is shown that flip is delayed with dimensions which is encouraging from the observational point because all the evidences from different cosmic probes point to a very late acceleration. Fixing the initial conditions we get QCDM, ?CDM and also Phantom like cosmology in a single frame work. This is, however, a consequences of the presence of extra dimensions. Moreover, our solutions reduce to the 4D models when extra dimensions are absent. © 2010 American Institute of Physics.


Panigrahi D.,Sree Chaitanya College | Panigrahi D.,Jadavpur University
International Journal of Modern Physics D | Year: 2015

The thermodynamical behavior of the variable Chaplygin gas (VCG) model is studied, using an equation-of-state (EoS) like P = - B/ρ, where B = B0V-n/3. Here B0 is a positive universal constant, n is also a constant and V is the volume of the fluid. From the consideration of thermodynamic stability, it is seen that only if the values of n are allowed to be negative, then (∂P/∂V)S < 0 throughout the evolution. Again thermal capacity at constant volume cV shows positive expression. Using the best fit value of n = -3.4 as previously found by Guo and Zhang (Phys. Lett. B. 645 (2007) 326) gives that the fluid is thermodynamically stable throughout the evolution. The effective EoS for the special case of n = 0 goes to Λ Cold Dark Matter (ΛCDM) model. Again for n < 0, it favors phantom-like cosmology which is in agreement with the current SNe Ia constraints like VCG model. The deceleration parameter is also studied in the context of thermodynamics and the analysis shows that the flip occurs for the value of n < 4. Finally, the thermal EoS is discussed which is an explicit function of temperature only. It is also observed that the third law of thermodynamics is satisfied in this model. As expected, the volume increases as temperature falls during adiabatic expansions. In this case, for T → 0, the thermal EoS reduces to (- 1 + n/6), which is identical with the EoS for the case of large volume. © 2015 World Scientific Publishing Company.


Das M.,Sree Chaitanya College | Pal S.,Human Genetic Engineering Research Center | Ghosh A.,Visva Bharati University
Journal of Nutrition, Health and Aging | Year: 2012

Objectives: The present community-based cross-sectional study was aimed to study the interaction of physical activity level (PAL) and metabolic syndrome (MS) among the adult Asian Indians. Methods: A total of 448 adult (> 30 years) individuals (males and females) inhabiting in and around Calcutta, India participated in the study. Anthropometric measures, blood pressure, metabolic profiles and intake of dietary fatty acids were obtained from participants using standard guidelines. Metabolic syndrome (MS) was defined accordingly. The dietary intake (gram/week) of fatty acids namely total fat (TFA); saturated fatty acids (SFA); monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were obtained using nutritive values of Indian foodstuffs. Physical activity level (PAL) was categorized in to three different level: 1) high PAL - who exercised regularly and had physically demanding occupation 2) moderate PAL - who either exercised regularly or had physically demanding occupation, and 3) low PAL - who neither exercised regularly nor had physically demanding occupation. Results: The prevalence of MS was found to be inversely related with PAL. Individuals with low PAL had higher prevalence of MS as compared to their counterparts. Moreover individuals with low PAL had significantly higher BMI, WC, WHR as well as TFA and SFA than individuals with moderate and high PAL. Conclusion: PAL is playing a vital role in the constellation of risk factors associated with MS. Habitual physical activity may be beneficial to prevent growing incidence of MS phenotypes in people of Asian Indian origin. © 2012 Serdi and Springer Verlag France.


Das M.,Sree Chaitanya College | Pal S.,Human Genetic Engineering Research Center | Ghosh A.,Visva Bharati University
Journal of Cardiovascular Disease Research | Year: 2012

Background: Our objective was to test the association between familial risk of type 2 diabetes mellitus (T2DM) and the prevalence of metabolic syndrome (MS) in adult Asian Indians. Materials and Methods: A total of 448 adult (>30 years) individuals (257 males and 191 females) participated in the study. Familial risk of T2DM was classified into three groups viz., 1=both parents affected; 2=parent and/or siblings affected and 3=none or no family history for T2DM. Anthropometric measures, blood pressures, fasting blood glucose and metabolic profiles were studied using standard techniques. MS was defined accordingly. The prevalence of MS phenotypes was estimated and compared among the three familial risk strata. Results: Individuals with a history of both parents affected from diabetes had significantly higher (P<0.001) body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and fasting blood glucose (FBG; P=0.035) than individuals having no family history of T2DM. Significant difference was also noticed between individuals with and without MS according to the family history of diabetes (P<0.001). Differences were evident between individuals who fulfilled all the MS criteria (P=0.001) and individuals with only one or two criteria (phenotypes) according to family history of T2DM. Conclusion: Family history of T2DM had significant effect on individuals with MS as compared to their counterparts (individuals having no family history of T2DM). It therefore seems reasonable to argue that family history of T2DM could be useful as a predictive tool for early diagnosis and prevention of MS in Asian Indian population.


Das M.,Sree Chaitanya College | Pal S.,Human Genetic Engineering Research Center | Ghosh A.,Visva Bharati University
Journal of Cardiovascular Disease Research | Year: 2010

Objective: The present community-based cross-sectional study was aimed to examine the association of metabolic syndrome (MS) with obesity measures, metabolic profiles, and intake of dietary fatty acids in Asian Indian population. Patients and Methods: A total of 350 adult (30 years and above) individuals (184 males and 166 females) inhabiting in and around Kolkata, India participated in this study. MS was defined using the protocol specifically designed for Asian Indian population. Results: The prevalence of MS in the study was 31.4%. The prevalence was significantly higher (P < 0.01) in females (48.2%) as compared to males (16.3%). It was observed that males without MS had significantly higher mean waist circumference (WC P < 0.05); waist-hip ratio (WHR; P < 0.001); triglyceride (TG; P < 0.05); very low density lipoprotein cholesterol (VLDLc; P < 0.05) and fasting blood glucose (FBG; P < 0.01) as compared to females without MS. Significant differences were also observed for dietary intake of total fatty acids (TFA; P < 0.001); saturated fatty acids (SFA; P < 0.001) and polyunsaturated fatty acids (PUFA; P < 0.001) between individuals with and without MS. However, no significant association was observed in individuals with MS after controlling for age and sex. On the other, WC and body mass index (BMI) had significant correlation with SFA: mono unsaturated fatty acids (MUFA; P < 0.01) in individuals without MS even after controlling for age and sex. Conclusion: It seem reasonable to argue that while dealing with MS in Asian Indians, clinicians should consider obesity measures, metabolic profiles and dietary fatty acids simultaneously.


Kar T.K.,Bengal Engineering and Science University | Chattopadhyay S.K.,Sree Chaitanya College
Comptes Rendus - Biologies | Year: 2010

Within the framework of a general equilibrium model we study the long-run dynamics of a prey-predator model in the presence of an alternative prey. Our results show that sustainability, i.e. a positive value of the population in the long run, essentially depends on individual harvesting efforts and digesting factors relative to alternative prey. A detailed bifurcation analysis evidences the richness of possible long-run dynamics. Our model clearly shows that the role of an alternative prey must be taken into consideration when studying prey-predator dynamics. © 2010 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.


Sarkar E.,Sree Chaitanya College | Chatterjee S.N.,Sree Chaitanya College | Chakraborty P.,Sree Chaitanya College
Turkish Journal of Botany | Year: 2012

Cassia tora L. (CT) is a widely growing weed in India with medicinal value and has been reported to show allelopathic potential causing biological suppression on crops. The present study was conducted to observe its suppression on Brassica campestris L. (mustard). The rate of seed germination and the root length, shoot length, chlorophyll content, fresh weight (FW), dry weight (DW), and relative water content (RWC) of 10-day-old mustard seedlings were observed aft er treatment with aqueous extracts of the roots, leaves, and seeds of CT and compared with control sets treated with distilled water. A confirmatory chemical test was conducted to determine the presence of phenols, ketones, acids, and alcohols in the CT plant extracts. Diff erent concentrations of the extracts showed inhibition (up to 100%) or deterioration in all of the parameters. Roots were more aff ected than shoots and the extract taken from leaves was more suppressive than that taken from other plant parts. The FW, DW, and RWC were considerably reduced upon treatment with the tested extracts. The extracts (>25%) also caused a reduction in the chlorophyll content. The overall results indicate the possible suppressive effect of allelochemicals (phenols, ketones, acids, and alcohols) present in CT on mustard. The overall results with regard to mustard plants followed the same trend of concentrationdependent inhibition in the order of leaf > seed > root.


Pahari U.K.,Sree Chaitanya College | Kar T.K.,Bengal Engineering and Science University
Nonlinear Dynamics | Year: 2013

In the present paper, we study a dynamic reaction model in which (i) the predator is provided with an alternative food in addition to the prey species, (ii) the predator is harvested, and (iii) a tax is imposed to regulate the system. The existence of possible steady states along with their local as well as global stability is discussed for both the exploited and unexploited systems. Boundedness of the system is also discussed. It is seen that the system undergoes a Hopf bifurcation by the addition of alternative prey and the criteria for the Hopf-bifurcation is also discussed. Optimal tax policy is discussed using Pontryagin's maximal principle. Finally, some numerical simulations are given to show the consistency with theoretical analysis. © 2013 Springer Science+Business Media Dordrecht.

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