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Solution structure of the tachykinin peptide eledoisin
Both the aqueous and the lipid-induced structure of eledoisin, an undecapeptide of mollusk origin, have been studied by two-dimensional proton nuclear magnetic resonance spectroscopy and distance geometry calculations. Unambiguous nuclear magnetic resonance assignments of protons have been made with the aid of correlation spectroscopy experiments and nuclear Overhauser effect spectroscopy experiments. The distance constraints obtained from the nuclear magnetic resonance data have been utilized in a distance geometry algorithm to generate a family of structures, which have been refined using restrained energy minimization and dynamics. These data show that, while in water and dimethyl sulfoxide, eledoisin prefers to be in an extended chain conformation, whereas in the presence of perdeuterated dodecylphosphocholine micelles, a membrane model system, helical conformation is induced in the central core and C-terminal region (K4-M11) of the peptide. N terminus, though less defined, also displays some degree of order and a possible turn structure. The conformation adopted by eledoisin in the presence of dodecylphosphocholine micelles is similar to the structural motif typical of neurokinin-2 selective agonists and with that reported for kassinin in hydrophobic environment. -
Solutions for time-fractional coupled nonlinear Schringer equations arising in optical solitons
In this work, an efficient novel technique, namely, the q-homotopy analysis transform method (q-HATM) is applied to obtain analytical solutions for a system of time-fractional coupled nonlinear Schringer (TF-CNLS) equations with the time-fractional derivative taken in the Caputo sense. This system of equations incorporate nonlocality behaviors which cannot be modeled under the framework of classical calculus. With numerous important applications in nonlinear optics, it describes interactions between waves of different frequencies or the same frequency but belonging to different polarizations. We first establish existence and uniqueness of solutions for the considered time-fractional problem via a fixed point argument. To demonstrate the effectiveness and efficiency of the q?HATM, two cases each of two time-fractional problems are considered. One important feature of the q?HATM is that it provides reliable algorithms which can be used to generate easily computable solutions for the considered problems in the form of rapidly convergent series. Numerical simulation are provided to capture the behavior of the state variables for distinct values of the fractional order parameter. The results demonstrate that the general response expression obtained by the q?HATM contains the fractional order parameter which can be varied to obtain other responses. Particularly, as this parameter approaches unity, the responses obtained for the considered fractional equations approaches that of the corresponding classical equations. 2021 The Physical Society of the Republic of China (Taiwan) -
Solvent free microwave assisted synthesis and evaluation of potent antimicrobial activity of 1,11H-pyrimido[4,5-a]carbazol-2-ones, 1,11H-pyrimido [4,5-a]carbazol-2-thiones and pyrazolo[3,4-a]carbazoles
Microwave assisted condensation of urea, thiourea and hydrazine hydrate with 1-chloro-2-formyl carbazoles in the presence of PTSA as catalyst yields 1,11H-pyrimido[4,5-a]carbazol-2-ones, 1,11H-pyrimido[4,5-a]carbazol-2-thiones and pyrazolo[3,4-a]carbazoles, respectively. The structures of the synthesized compounds have been confirmed on the basis of elemental analysis and spectral data. All the synthesized compounds have been evaluated for their antibacterial and antifungal activities. Some of the synthesized compounds 2a-g and 3a-g exhibit significant antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. The compounds 2a-g and 3a-g exhibit good antifungal activity against Candida albicans, Aspergillus flavus. Pyrazolo[3,4-a]carbazoles 4a-g register good antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. The compound 4e indicate maximum activity of 20 and 24 mm at 500 and 1000?g/disc, respectively, against Lipomyces lopofera fungi. -
Solvent polarity, structural and electronic properties with different solvents and biological studies of 3,3,5-triphenylfuran-2(3H)-one- cancers of the blood cells
The current work comprises synthesis, characterization and computational evaluation on 3,3,5-triphenylfuran-2(3H)-one with density functional theory (DFT) as the underlying principle. The theoretical optimized structure and corresponding geometrical parameters were obtained. Multiwfn 3. 8 was employed to conduct topological investigations such as R D G, E L F, L O L, and charge transfer analyses, which are used to identify the excited states, non-covalent interactions and important bonding regions in the molecule. Effect of solvents on the variation in molecular properties were studied with different polar solvents, with the IEFPCM model, as furanones interact with more polar solvents. The solvation studies were shown to impact on F M O, UV, M E P, and NLO analysis and thus between gas and solvent phases, a variation is observed in the properties under study. N B O studies were analysed to identify the natural bond orbitals within the molecule that contribute the maximum to the stabilization energy of the title compound. Pharmacological evaluation using readily available online tools that include SwissADME, Pre-ADMET, GUSAR, and ADMETLab 2.0 to determine the medicinal chemistry properties of the molecule was done. Furthermore, molecular docking onto chosen anticancer protein targets is performed utilising the softwares AutoDock Suite. PyMOL,and Discovery Studio Visualizer, is used to determine the best docked conformations that suggest potential capability of the compound to inhibit these proteins and protect the body from cancerous growths. 2022 Elsevier B.V. -
Solvent-solute interaction, thermodynamic behaviour, structural, chemical and anti-cancer biological properties of 3(2H)-furanone derivatives
In this work, the structures, reactivities, and electronic and biological properties of the 3(2H)-furanone derivatives, 2-hydroxy-2,5-diphenyl-4-(phenylamino)furan-3(2H)-one (HDPF), 2-methoxy-2,4,5-triphenylfuran-3(2H)-one (MTPF), 3-oxo-2,4,5-triphenyl-2,3-dihydrofuran-2-yl acetate (OTDF), and 2-chloro-2,4,5-triphenylfuran-3(2H)-one (CTPF), are explored via theoretical investigations using DFT (Density Functional Theory) techniques as the main tools for the study. The DFT studies include geometry optimisation, FMO (Frontier Molecular Orbital) analysis, theoretical UV studies, molecular electrostatic potential (MEP) investigations, non-linear optical (NLO) analyses, and the evaluation of thermodynamic parameters. Multiwfn 3.8 software is utilised to conduct the topological analyses. The ADME (Absorption, Distribution, Metabolism, Excretion) profiles are produced with the SwissADME online tool. The target proteins, MCL-1 (Myeloid cell leukemia-1), BCL-2 (B-cell lymphoma-2), and myeloblastin, are docked with the title molecules using AutoDock 1.5.6. 2023 Elsevier B.V. -
Solvent-solute polarity, electrophilic, steric effects, reactive sites, themodynamic quantities discussion and biological evaluation of lung cancer antiproliferative activities of spirobrassinin derivatives
The current study of spirobrassinin and its related compounds, 1-methoxyspirobrassinol and the 5-bromo analogue of methoxyspirobrassinin is performed to reveal a comparison among these molecules to understand which is the most reactive and bioactive. DFT (Density Functional Theory) studies comprising geometry optimisation (energy minimisation), FMO (Frontier Molecular Orbital) Analysis, theoretical UV analysis, NLO (Non-Linear Optics), NBO (Natural Bond Orbital) and thermodynamics studies are performed using Gaussian 09W. IEFPCM model is employed to investigate the solvent effect on the reactivity and stability of the title compounds. ADME profiles are generated using SwissADME, PreADMET and ADMETLab 2.0. Interesting lung cancer target proteins are docked with the title compounds is finally performed to obtain insight into the molecules' anticancer potential. 2023 Elsevier B.V. -
Solving Wordle Using Actor-Critic Reinforcement Learning
The popular word-game Wordle poses a difficult sequential decision-making problem with enormous discrete action spaces and partial feedback. In order to solve Wordle as efficiently as possible, this work explores the use of actor-critic reinforcement learning techniques. We develop two actor-critic variations, Vanilla Actor-Critic (AC) and Advantage Actor-Critic (A2C), and formulate Wordle as a Markov Decision Process. Through curriculum training on increasingly larger vocabulary, our method filters out invalid actions and guides learning by combining neural networks and symbolic reasoning. While the AC agent has 42.35 % success with an average guess of 4.85, the A2C agent has a 46.05 % success rate averaging 5.31 guesses per successful game. We show that, especially in the worst-case situations, batch-based A2C performs more robustly than stepbased AC. By effectively scaling from tiny vocabularies (50 words) to the entire Wordle lexicon (14,855 words), our neuro-symbolic technique demonstrates the efficacy of curriculum learning for challenging word games. 2025 IEEE. -
Some case studies for non-parametric tests for ordinal data /
International Journal Of Advanced Research In Engineering Technology & Sciences, Vol.2, Issue 7, pp.309-313, ISSN No: 2394-2819. -
Some case studies on importance of variables and scales of measurement in social sciences research /
International Advanced Research Journal In Science, Engineering And Technology, Vol.2, Issue 3, pp.34-37, ISSN No: 2393-8021 (Online) 2394-1588 (Print). -
Some characterizations of Gallai graphs
Gallai graph of a graph G is a graph whose vertices are the edges of G and the adjacency of the vertices depends on whether they are part of a triangle or not in G. We find some forbidden subgraph characterization of graphs for which Gallai graph is either a trivially perfect graph or a 3-sun-free graph or an interval graph. 2020 Author(s). -
Some examples in usage of parametric tests /
International Journal of Research In Commerce IT And Management., Vol.5, Issue 11, ISSN No: 2231-5736. -
Some graphs with super vertex sum number 2
In this paper we give optimal super vertex sum labeling scheme for super subdivision of bi-star, path union of spider and algorithm to construct super vertex sum labeling of super subdivision of Caterpillar. 2018 Academic Publications. -
Some improper injective coloring parameters of graphs
Any vertex coloring protocol of a graph can be viewed as a random experiment of assigning colors to the vertices, whose random variable is defined as the number of vertices assigned a specific color in that coloring. Based on this idea, the statistical parameters of mean and variance have been extended to chromatic mean and chromatic variance for various proper vertex colorings of graphs in the literature. In this paper, the ideas of chromatic mean and chromatic variance of graphs concerning their improper injective coloring are introduced and determined for certain standard graphs. World Scientific Publishing Company. -
Some interesting case studies using bayes theorem /
International Journal Of Scientific Research, Vol.4, Issue 4, pp.522-523, ISSN No: 2277-8179. -
Some New Results on ?(k) -Coloring of Graphs
Let ? be the minimum number of distinct resources or equipment such as channels, transmitters, antennas and surveillance equipment required for a system's stability. These resources are placed on a system. The system is stable only if the resources of the same type are placed far away from each other or, in other words, they are not adjacent to each other. Let these distinct resources represent different colors assigned on the vertices of a graph G. Suppose the available resources, denoted by k, are less than ?. In that case, placing k resources on the vertices of G will make at least one equipment of the same type adjacent to each other, which thereby make the system unstable. In ?(k)-coloring, the adjacency between the resources of a single resource type is tolerated. The remaining resources are placed on the vertices so that no two resources of the same type are adjacent to each other. In this paper, we discuss some general results on the ?(k)-coloring and the number of bad edges obtained from the same for a graph G. Also, we determine the minimum number of bad edges obtained from ?(k)-coloring of few derived graph of graphs. The number of bad edges which result from a ?(k)-coloring of G is denoted by bk(G). 2023 World Scientific Publishing Company. -
Some new results on anti-adjacency spectra of regular graphs
The anti-adjacency matrix A*(G) of a simple graph G with V (G) = {v1,v2,v3,vn}, is a square matrix of order n with rows and columns indexed by V (G), where the (i,j)-entry (i?j) is 1, if the vertices vi and vj are not adjacent to each other and 0, otherwise. The (i,i)- entry of A*(G) is 1. The anti-adjacency eigenvalues of G are the eigenvalues obtained from the matrix A*(G) and the corresponding spectra is called the anti-adjacency spectra of G, denoted by a-spec(G). In this paper, we discuss the anti-adjacency spectra of join and disjoint union of regular graphs. The anti-adjacency spectra of bipartite regular graphs, line graphs of regular graphs and strongly regular graphs are also discussed. 2026 World Scientific Publishing Company. -
Some new results on equitable coloring parameters of graphs
An equitable coloring of a graph G is a proper vertex coloring C of G such that the cardinalities of any two color classes in G with respect to C differ by at most one. Coloring the vertices of a graph G subject to given conditions can be considered as a random experiment. In this context, a discrete random variable X can be defined as the color of a vertex chosen at random, with respect to the given type of coloring of G and a probability mass function for this random variable can be defined accordingly. In this paper, we discuss two statistical parameters of the powers of certain graph classes with respect to their equitable colorings. 2019, Univerzita Komenskeho. All rights reserved.




