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21.
Fully β-pyrrole chlorinated corrole was obtained via reaction of the cobalt(iii) complex of 5,10,15-tris(pentafluorophenyl)corrole with chlorine. The structural and electronic effects of chlorination are reported, together with the coordination chemistry of this complex.  相似文献   
22.
A cycle C in a graph G is extendable if there is some other cycle in G that contains each vertex of C plus one additional vertex. A graph is cycle extendable if every non‐Hamilton cycle in the graph is extendable. A balanced incomplete block design, BIBD, consists of a set V of v elements and a block set of k‐subsets of V such that each 2‐subset of V occurs in exactly λ of the blocks of . The block‐intersection graph of a design is the graph having as its vertex set and such that two vertices of are adjacent if and only if their corresponding blocks have nonempty intersection. In this paper, we prove that the block‐intersection graph of any BIBD is cycle extendable. Furthermore, we present a polynomial time algorithm for constructing cycles of all possible lengths in a block‐intersection graph.  相似文献   
23.
Metal oxide nanoparticles synthesized by the biological method represent the most recent research in nanotechnology. This study reports the rapid and ecofriendly approach for the synthesis of CeO2 nanoparticles mediated using the Abelmoschus esculentus extract. The medicinal plant extract acts as both a reducing and stabilizing agent. The characterization of CeO2 NPs was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxicity of green synthesized CeO2 was assessed against cervical cancerous cells (HeLa). The exposure of CeO2 to HeLa cells at 10–125 µg/mL caused a loss in cellular viability against cervical cancerous cells in a dose-dependent manner. The antibacterial activity of the CeO2 was assessed against S. aureus and K. pneumonia. A significant improvement in wound-healing progression was observed when cerium oxide nanoparticles were incorporated into the chitosan hydrogel membrane as a wound dressing.  相似文献   
24.
Although some of the earliest Estimation of Distribution Algorithms (EDAs) utilized bivariate marginal distribution models, up to now, all discrete bivariate EDAs had one serious limitation: they were constrained to exploiting only a limited O(d) subset out of all possible \(O(d^{2})\) bivariate dependencies. As a first we present a family of discrete bivariate EDAs that can learn and exploit all \(O(d^{2})\) dependencies between variables, and yet have the same run-time complexity as their more limited counterparts. This family of algorithms, which we label DICE (DIscrete Correlated Estimation of distribution algorithms), is rigorously based on sound statistical principles, and particularly on a modelling technique from statistical physics: dichotomised multivariate Gaussian distributions. Initially (Lane et al. in European Conference on the Applications of Evolutionary Computation, Springer, 1999), DICE was trialled on a suite of combinatorial optimization problems over binary search spaces. Our proposed dichotomised Gaussian (DG) model in DICE significantly outperformed existing discrete bivariate EDAs; crucially, the performance gap increasingly widened as dimensionality of the problems increased. In this comprehensive treatment, we generalise DICE by successfully extending it to multary search spaces that also allow for categorical variables. Because correlation is not wholly meaningful for categorical variables, interactions between such variables cannot be fully modelled by correlation-based approaches such as in the original formulation of DICE. Therefore, here we extend our original DG model to deal with such situations. We test DICE on a challenging test suite of combinatorial optimization problems, which are defined mostly on multary search spaces. While the two versions of DICE outperform each other on different problem instances, they both outperform all the state-of-the-art bivariate EDAs on almost all of the problem instances. This further illustrates that these innovative DICE methods constitute a significant step change in the domain of discrete bivariate EDAs.  相似文献   
25.
Journal of Solid State Electrochemistry - Scientists are increasingly interested in improving electroactive technologies for supercapacitor applications, since energy storage devices have improved...  相似文献   
26.
The candid intension of this article is to inspect the heat and mass transfer of a magnetohydrodynamic tangent hyperbolic nanofluid. The nanofluid flow has been assumed to be directed by a wedge on its way. In addition, the collective stimulus of the convective heating mode with thermal radiation is inspected. The governing set of PDEs is rendered into that of the coupled nonlinear ODEs. The resulting ordinary differential equations are then solved by the well known shooting technique for two different cases; the flow over a static wedge and flow over a stretching wedge. The impact of intricate physical parameters on the velocity, temperature and concentration profiles is analyzed graphically. It is noticed that the intensifying values of the generalized Biot number, Brownian motion parameter, thermophoresis parameter and Weissenberg number enhances the dimensionless temperature profile.  相似文献   
27.
Research on Chemical Intermediates - Zinc oxide-doped tin dioxide (ZnO–SnO2) nanomaterials were prepared by a sol–gel method with and without different amounts (0.5, 1.0 and...  相似文献   
28.
The use of insects as a feasible and useful natural product resource is a novel and promising option in alternative medicine. Several components from insects and their larvae have been found to inhibit molecular pathways in different stages of cancer. This study aimed to analyze the effect of aqueous and alcoholic extracts of Vespa orientalis larvae on breast cancer MCF7 cells and investigate the underlying mechanisms. Our results showed that individual treatment with 5% aqueous or alcoholic larval extract inhibited MCF7 proliferation but had no cytotoxic effect on normal Vero cells. The anticancer effect was mediated through (1) induction of apoptosis, as indicated by increased expression of apoptotic genes (Bax, caspase3, and p53) and decreased expression of the anti-apoptotic gene Bcl2; (2) suppression of intracellular reactive oxygen species; (3) elevation of antioxidant enzymes (CAT, SOD, and GPx) and upregulation of the antioxidant regulator Nrf2 and its downstream target HO-1; (4) inhibition of migration as revealed by in vitro wound healing assay and downregulation of the migration-related gene MMP9 and upregulation of the anti-migratory gene TIMP1; and (5) downregulation of inflammation-related genes (NFκB and IL8). The aqueous extract exhibited the best anticancer effect with higher antioxidant activities but lower anti-inflammatory properties than the alcoholic extract. HPLC analysis revealed the presence of several flavonoids and phenolic compounds with highest concentrations for resveratrol and naringenin in aqueous extract and rosmarinic acid in alcoholic extract. This is the first report to explain the intracellular pathway by which flavonoids and phenolic compounds-rich extracts of Vespa orientalis larvae could induce MCF7 cell viability loss through the initiation of apoptosis, activation of antioxidants, and inhibition of migration and inflammation. Therefore, these extracts could be used as adjuvants for anticancer drugs and as antioxidant and anti-inflammatory agents.  相似文献   
29.
Treatment of microbial infections and inflammatory conditions have many challenges in terms of efficacy and safety issues. Novel approaches such as nanoparticles based drug delivery system have shown promising results to solve some of these problems. The aim of this study was to exploit the efficacy of the synthesized silver nanoparticles. In this study, silver nanoparticles (AgNPs) were biosynthesized using root extract (aqueous) of Duchesnea indica. They were characterized using different techniques such as, ultraviolet–visible (UV–Vis) spectrophotometry, transmission and scanning electron microscopy (TEM and SEM), X-ray diffractometer (XRD), energy dispersive X-ray spectroscopy (EDX), fourier-transform infrared spectroscopy (FTIR) and zetasizer. The UV–Vis spectra gave a characteristic peak at 423 nm; XRD confirmed its crystalline structure; FTIR confirmed the involvement of phytochemicals in their capping and reduction; TEM images confirmed their spherical shape with average width of 20.49 nm and average area of 319.25 nm2. Various biological activities were performed on these NPs, such as antimicrobial, anti-inflammatory, analgesic and muscle relaxant, which showed significant results as follow. Among bacterial strains, Salmonella typhi (MIC: 0.01 mg/ml) and Escherichia coli (MIC: 0.01 mg/ml), while among that of fungal Microsporum canis (MIC: 0.53 mg/ml) and Alternaria alternata (MIC: 0.51 mg/ml) were most susceptible. The AgNPs showed maximum anti-inflammatory activity (46.15 and 56.85%) at 20 mg/kg after 3 and 5 h of drug administration, comparable to that of standard. In-vivo model exhibited concentration dependent inhibition of both COX-2 and 5-LOX enzymes. Similarly, it exhibited maximum analgesic activity (54.24%) at 20 mg/kg dose after 60 min. of pain induction. Furthermore, they depicted maximum muscle relaxation (P < 0.01) after 60 and 90 min of drug administration. Above results suggest that these AgNPs can be studied further for the development of more effective and safe formulations.  相似文献   
30.
This article presents a new heteroleptic Zn(II) dithiocarbamate ( 1 ) having molecules linked together via H···H and π···π interactions to form a giant hexanuclear macrocycle. These macrocycles are connected together through S···H interactions to offer a unique two‐dimensional cloth‐like interwoven architecture in the solid state. The redox behavior of the complex deposited on the surface of a glassy carbon electrode was investigated in different pH media. The analyte was found to oxidize and reduce in a pH‐dependent irreversible manner. On the basis of the electrochemical findings, redox mechanistic pathways were proposed.  相似文献   
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