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51.
A network with its arc lengths as imprecise number, instead of a real number, namely, interval number and triangular fuzzy
number is considered here. Existing ideas on addition and comparison between two imprecise numbers of same type are introduced.
To obtain a fuzzy shortest path from a source vertex to all other vertices, a common algorithm is developed which works well
on both types of imprecise numbers under consideration. In the proposed algorithm, a decision-maker is to negotiate with the
obtained fuzzy shortest paths according to his/her view only when the means are same but the widths are different of the obtained
paths. Otherwise, a fuzzy optimal path is obtained to which the decision-maker always satisfies with different grades of satisfaction.
All pairs fuzzy shortest paths can be found by repeated use of the proposed algorithm. 相似文献
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Masataka?Sugimoto Kengo?Ishizuka Keisuke?Hatano Sathish?K.?Sukumaran Yuji?AokiEmail author 《Rheologica Acta》2017,56(10):779-785
The viscoelastic properties of poly(methyl methacrylate) (PMMA)/grafted poly(butyl acrylate) (PBA) nanoparticle systems were investigated. The rubber particles consist of PBA core (60 nm in diameter) and grafted PMMA shell. The grafting degree, defined as the weight ratio of grafted PMMA to PBA particles, ranges from 0.8 to 1.5. Two series of samples, A series with 7.5 wt.% of PBA content and B series with 12 wt.% of PBA content, were used. The systems exhibited fast and slow relaxation process, the former reflecting the relaxation of the matrix PMMA chains and the latter being attributed to grafted PBA particles. For A series samples, time-temperature superposition (TTS) was held well over the frequency (ω) and temperature (T) ranges measured. However, for B series samples, TTS was not satisfied at low ω due to the particle-particle interaction of grafted PBA particles, although the samples obeyed TTS at high ω associated with the relaxation with entanglement of matrix PMMA. At high T and low ω region, the B series samples showed a sol-gel transition at elevating T and the critical gel behavior characterized with a power-law relationship, G′ = G″/tan(nπ/2) ∝ ωn, was observed. This behavior suggested formation of a self-similar, fractal structure of grafted PBA particles. The critical gel temperature (T gel) and the critical exponent (n) were determined for the B series samples. TEM observations revealed that as-prepared A and B samples had well-dispersed particles but the B samples after viscoelastic measurements had fragmented networks of the PBA particles, confirming that the sol-gel transition occurred for the PMMA/grafted PBA systems at elevating T. 相似文献
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Salga SM Ali HM Abdullah MA Abdelwahab SI Wai LK Buckle MJ Sukumaran SD Hadi AH 《Molecules (Basel, Switzerland)》2011,16(11):9316-9330
Some novel Schiff bases derived from 1-(2-ketoiminoethyl)piperazines were synthesized and characterized by mass spectroscopy, FTIR, UV-Visible, 1H and 13C-NMR. The compounds were tested for inhibitory activities on human acetylcholinesterase (hAChE), antioxidant activities, acute oral toxicity and further studied by molecular modeling techniques. The study identified the compound (DHP) to have the highest activity among the series in hAChE inhibition and DPPH assay while the compound LP revealed the highest activity in the FRAP assay. The hAChE inhibitory activity of DHP is comparable with that of propidium, a known AChE inhibitor. This high activity of DHP was checked by molecular modeling which showed that DHP could not be considered as a bivalent ligand due to its incapability to occupy the esteratic site (ES) region of the 3D crystal structure of hAChE. The antioxidant study unveiled varying results in 1,1-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. This indicates mechanistic variations of the compounds in the two assays. The potential therapeutic applications and safety of these compounds were suggested for use as human acetylcholinesterase inhibitors and antioxidants. 相似文献
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Kaliraj Chandran Azar Zochedh Sureba Sukumaran Asath Bahadur Sultan Thandavarayan Kathiresan 《International journal of quantum chemistry》2024,124(1):e27299
The main aim of this study is to identify the structural stability of allo-ocimenol and its molecular reactivity against breast cancer-associated proteins to confirm its anti-cancer capability using density function theory and molecular docking analysis. The structural optimization was carried out via the DFT/B3LYP technique with a 6-311++G (d,p) basis set. The molecular geometry and vibrational assignments of the Allo-Ocimenol molecule were analyzed through density functional theory (DFT). Through optimized molecular structure, the vibrational frequencies (FT-IR and FT-Raman) were assigned and related with experimentally observed vibrational frequencies and the UV spectrum was computed and experimentally confirmed. The allo-ocimenol's reactive activity was further analyzed through a computed molecular electrostatic potential surface. Utilizing the HOMO-LUMO energies and molecular electrostatic potential energy gap, the reactivity and molecular stability of the allo-ocimenol molecule was calculated. Mulliken and natural population analyses were used to determine the charge distribution across the allo-ocimenol atoms. The natural bond orbitals were used to demonstrate the bioactivity of the titled molecule. RDG evaluation was used to examine the weak interactions of the allo-ocimenol molecule. ELF and LOL analyses were utilized to investigate the topology of the allo-ocimenol molecule. Thermodynamic evaluation has been utilized to acquire values and asses the thermodynamic parameters that reveal the thermal stability of the title molecule. Allo-Ocimenol's anti-microbial activity was assessed through an in-vitro disc diffusion method, and its tumor inhibitory and pharmacokinetic properties were evaluated through an in-silico approach using molecular docking and ADMET investigation. Zones of clearance were seen in anti-microbial analyses at various concentrations, and the breast cancer target protein NAMPT established the greatest binding potential, with a docking value of −7.4 Kcal mol−1. 相似文献
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Pradeesh Sukumaran Archana G. Nair Devi M. Chinmayee I. Mini Swapna T. Sukumaran 《Applied biochemistry and biotechnology》2012,167(6):1795-1801
Bidens biternata, belonging to the family Asteraceae, is an erect annual herb, up to 1 cm in height, and a widespread weed of cultivated areas. This plant is common, particularly in the Western Ghats regions of Kerala state in India. It is used as a leafy vegetable by the Paniya and Kattunaayika tribes of Waynadu Districts in Kerala and also to cure hepatitis, cold, cough, dysentery, etc. The multiplication and utilization of this leafy vegetable will help to overcome the nutritional deficiency problem and also to maintain the biodiversity. For effective biochemical analysis, plant extract was taken using different solvents. Various phytochemicals like reducing sugar, glycosides, flavonoids, alkaloids, tannins, steroids, terpenoids, coumarins, saponins, anthraquinones, phlobatannins and iridoids were estimated. Different nutritional factors like total carbohydrates, total proteins, total reducing sugar, different amino acids, free fatty acids, crude fibre, lipids, total moisture content, vitamins, etc. were tested by standard estimation methods. Anti-nutritional factors like phytic acid, total phenol, tannic acid, etc., were also estimated. Micronutrients and different pigments were quantified. The present studies revealed that this wild leafy plant has numerous nutritional factors with a low level of anti-nutritional factors. Therefore, this nutritive herb with diverse health-promoting compounds can be effectively utilized to overcome the nutritional deficiency problem around the globe. 相似文献