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371.
Santosh Biswas Sudip Samanta Joydev Chattopadhyay 《Journal of Applied Mathematics and Computing》2018,57(1-2):161-197
In this present article, we propose and analyze a cannibalistic predator–prey model with disease in the predator population. We consider two important factors for the dynamics of predator population. The first one is governed through cannibalistic interaction, and the second one is governed through the disease in the predator population via cannibalism. The local stability analysis of the model system around the biologically feasible equilibria are investigated. We perform global dynamics of the model using Lyapunov functions. We analyze and compare the community structure of the system in terms of ecological and disease basic reproduction numbers. The existence of Hopf bifurcation around the interior steady state is investigated. We also derive the sufficient conditions for the permanence and impermanence of the system. The study reveals that the cannibalism acts as a self-regulatory mechanism and controls the disease transmission among the predators by stabilizing the predator–prey oscillations. 相似文献
372.
In this paper, we study third power associative, antiflexible rings satisfying the identity (a,b,ac)?=?a(a,b,c). We prove that third power associative, antiflexible rings satisfying the identity (a,b,ac)?=?a(a,b,c) with characteristic ≠2,3 are associative of degree 5. As a consequence of this result, we prove that a third power associative semiprime antiflexible ring satisfying the identity (a,b,ac)?=?a(a,b,c) is associative. 相似文献
373.
Sandip Kumar Samanta Syed Samim Ali Ankita Gangopadhyay Kalipada Maiti Ajoy Kumar Pramanik Uday Narayan Guria 《Supramolecular chemistry》2019,31(5):349-360
A 3-indolylacrylate derivative, 3-IA, prepared by connecting an ethyl acrylate in 3-position of indole has been synthesised and characterised. Ethyl acrylate moiety acts as the Michael acceptor towards H2S, and the resultant addition product then participates in intramolecular cyclisation with the ester group at 2-position to form another new heterocyclic ring. Blue fluorescence of 3-IA turned into green in presence of H2S, leading to ratiometric behaviour of the fluorescent sensor with large stokes shift of 55 nm. Probe 3-IA has excellent selectivity towards H2S over other biothiols and other competing anions. Density function theory/time-dependent density function theory calculations were carried out to validate the reaction mechanism and the electronic properties of 3-IA. Importantly, the ratiometric probe 3-IA shows great promise in H2S detection by simple visual fluorescent inspection in filter paper-based protocol. The probe shows its excellent ability to detect H2S in different natural water samples. Furthermore, we have employed our probe to detect H2S for ratiometric imaging in live Vero cell. 相似文献
374.
Metal–organic frameworks (MOFs) have evolved as an exciting class of materials in the domain of porous materials. The unique features of these materials arise from the combined properties of metal ions/clusters and organic struts which form the building blocks of these fascinating architectures. Among other multifarious applications, MOFs have shown tremendous applications as sensory materials for a wide variety of species. The signal transduction induced mechanism in these confined nanospaces generate optical output in response to a particular analyte which can be detected by wide variety of detection techniques. Fluorometric methods of sensing is one of widely studied method over past few decades. MOF‐based fluorometric detection is a key research theme developed over the past few years. In this review, we give a brief overview of the recent developments of MOFs as “turn‐on” sensors for a wide range of analytes (viz. cations, anions, volatile organic compounds (VOCs), etc.). 相似文献
375.
Dutta SK Samanta S Mukhopadhyay S Burckel P Pinkerton AA Chaudhury M 《Inorganic chemistry》2002,41(11):2946-2952
The anionic cis-dioxovanadium(V) complex species LVO(2)(-) of a tridentate ONS ligand (H(2)L) can bind sodium ion in a bis-monodentate fashion like a bridging carboxylate group. The product [LVO(2)Na(H(2)O)(2)](infinity) (1) is a water soluble polymeric compound in which the complementary units are held together by the simultaneous use of hydrogen bonding and Coulombic interactions. Crystallographic characterization reveals that 1 is a single stranded helicate with LVO(2)(-) units forming the strand which surrounds the labile sodium ions that occupy the positions on the axis. In solution of protic solvents, viz. water and methanol, 1 is quite stable as indicated by electrical conductivity and (1)H NMR measurements. In aprotic solvents, viz. CH(3)CN, DMF, or DMSO, however, the extended hydrogen bonded network in 1 breaks apart and the helical structure collapses when irradiated with visible light. The product is a mixed-oxidation vanadium(IV/V) species obtained by photoinduced reduction as confirmed by EPR, time dependent (1)H NMR, and electronic spectroscopy. Compound 1 is a rare example of a nonnatural helix where hydrogen bonding interactions play a crucial role in stabilizing the single stranded polymeric structure such as that frequently observed in the biological world. 相似文献
376.
377.
By abstracting a connection between gauge symmetry and gauge identity on a noncommutative space, we analyse star (deformed)
gauge transformations with the usual Leibniz rule as well as undeformed gauge transformations with a twisted Leibniz rule.
Explicit structures of the gauge generators in either case are computed. It is shown that, in the former case, the relation
mapping the generator with the gauge identity is a star deformation of the commutative space result. In the latter case, on
the other hand, this relation gets twisted to yield the desired map. 相似文献
378.
M. Samanta 《Annals of the Institute of Statistical Mathematics》1973,25(1):301-319
Summary A method of estimating the location parameter in the univariate two sample problem when one sample is reduced to a frequency
distribution over a given set of class intervals has been developed by Bhattacharya [1]. In this paper we consider the problem
of estimating the vector of location parameters in the bivariate two sample problem. The research reported here is an extension
of Bhattacharya's work. 相似文献
379.
A Post‐Synthetically Modified MOF for Selective and Sensitive Aqueous‐Phase Detection of Highly Toxic Cyanide Ions 下载免费PDF全文
Avishek Karmakar Naveen Kumar Partha Samanta Aamod V. Desai Dr. Sujit K. Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):864-868
Selective and sensitive detection of toxic cyanide (CN?) by a post‐synthetically altered metal–organic framework (MOF) has been achieved. A post‐synthetic modification was employed in the MOF to incorporate the specific recognition site with the CN? ion over all other anions, such as Cl?, Br?, and SCN?. The aqueous‐phase sensing and very low detection limit, the essential prerequisites for an effective sensory material, have been fulfilled by the MOF. Moreover, the present detection level meets the standard set by the World Health Organization (WHO) for the permissible limit of cyanide concentration in drinking water. The utilization of MOF‐based materials as the fluorometric probes for selective and sensitive detection of CN? ions has not been explored till now. 相似文献
380.
T. Sinha Rituparna Kanungo C. Samanta Sudip Ghosh P. Basu H. Rebel 《Zeitschrift für Physik A Hadrons and Nuclei》1976,355(4):397-400
Alpha-particle scattering from the resonant (3 1 + ) and non-resonant continuum states of 6Li is studied at incident energy 10 MeV/A. The α + d breakup continuum part within the excitation energy E ex = 1.475–2.475 MeV is discretized in two energy bins. Unlike the results at higher incident energies, here the coupled-channel calculations show significant breakup continuum coupling effects on the elastic and inelastic scattering. It is shown that even when the continuum-continuum coupling effects are strong, the experimental data of the ground state and the resonant as well as discretized non-resonant continuum states impose stringent constraint on the coupling strengths of the non-resonant continuum states. 相似文献