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31.
Datura metel L. is an important medicinal plant of Solanaceae family which has extensive pharmacological properties. The present investigation was aimed to identify the presence of phytoconstituents and assess in vitro antibacterial, anti-biofilm, anti-diabetic, anti-inflammatory, antioxidant, cytotoxicity, and wound healing efficacy of D. metel leaves extract. Among different solvent extracts, methanolic extract showed higher amount of phenolic (124.61 ± 0.68 mg GAE/g), alkaloid (88.77 ± 1.01 mg AE/g), flavonoids (42.24 ± 0.18 mg QE/g), and tannins contents (38.72 ± 0.51 mg GAE/g). The extract exhibited not only significantly (P < 0.05) different antibacterial activities against pathogens tested but also showed maximum biofilm inhibition of 94, 88, and 92% against B. subtilis, MRSA, and E. coli, respectively. Anti-diabetic assay depicted 22.55 ± 0.62–79.41 ± 1.13% and 24.31 ± 1.47–72.59 ± 0.22% of α-amylase and α-glucosidase inhibition abilities of methanolic extract, respectively at varied concentrations. The methanolic extract showed potential anti-inflammatory effect (P < 0.05) by showing 28.11 ± 0.13, 34.94 ± 1.11, 55.73 ± 0.42, 73.28 ± 0.72, and 92.62 ± 1.33% of inhibition of protein denaturation at different concentrations with an IC50 value of 52.45 µg/mL. The extract revealed significant (P < 0.05) rate of ABTS scavenging, DPPH degradation, and reducing power assay in a concentration dependent manner. The cytotoxicity assay was demonstrated on L929 mouse fibroblast cell line and found > 90% of cell viability in the presence of methanolic extract, thereby indicating its non-toxicity effect. Wound healing assay indicated that methanolic extract at 50 µg/mL closed 100% of wound gap after 24 h with high rate of migration and proliferation. Furthermore, GC–MS chromatogram revealed the presence of several components in methanolic extract, including neophytadiene, hexadecanoic acid, and hentriacontane as principal phytoconstituents. In conclusion, methanolic extract of D. metel leaves could be used as potent therapeutic agent not only for treating metabolic diseases but also superficial chronic diabetic wounds.  相似文献   
32.
This article describes a dielectrophoresis (DEP)-based simulation and experimental study of human epidermal keratinocyte (HEK) cells for wounded skin cell migration toward rapid epithelialization. MyDEP is a standalone software designed specifically to study dielectric particles and cell response to an alternating current (AC) electric field. This method demonstrated that negative dielectrophoresis (NDEP) occurs in HEK cells at a wide frequency range in highly conductive medium. The finite element method was used to characterize particle trajectory based on DEP and drag force. The performance of the system was assessed using HEK cells in a highly conductive EpiLife suspending medium. The DEP experiment was performed by applying sinusoidal wave AC potential at the peak-to-peak voltage of 10 V in a tapered aluminum microelectrode array from 100 kHz to 1 MHz. We experimentally observed the occurrence of NDEP, which attracted HEK cells toward the local electric field minima in the region of interest. The DIPP-MotionV software was used to track cell migration in the prerecorded video via an automatic marker and estimate the average speed and acceleration of the cells. The results showed that HEK cell migration was accomplished approximately at 6.43 μm/s at 100 kHz with 10 V, and FDEP caused the cells to migrate and align at the target position, which resulted in faster wound closures because of the application of an electric field frequency to HEK cells in random locations.  相似文献   
33.
Hydroxyapatite-supported Ni-Ce-Cu catalysts were synthesised and tested to study their potential for use in the steam reforming of glycerol to produce hydrogen. The catalysts were prepared by the deposition-precipitation method with variable nickel, cerium, and copper loadings. The performance of the catalysts was evaluated in terms of hydrogen yield at 600°C in a tubular fixed-bed microreactor. All catalysts were characterised by the BET surface area, XRD, TPR, TEM, and FE-SEM techniques. The reaction time was 240 min in a fixed-bed reactor at 600°C and atmospheric pressure with a water-to-glycerol feed molar ratio of 8: 1. It was found that the Ni-Ce-Cu (3 mass %-7.5 mass %-7.5 mass %) hydroxyapatite-supported catalyst afforded the highest hydrogen yield (57.5 %), with a glycerol conversion rate of 97.3 %. The results indicate that Ni/Ce/Cu/hydroxyapatite has great potential as a catalyst for hydrogen production by steam reforming of glycerol.  相似文献   
34.
The authors scrutinize the steady, MHD flow of SiO2−MoS2/water hybrid nanofluid towards two different geometries i.e. a wedge and a cone. The Tiwari and Das model is implemented with a generalized–Fourier's model, popularized as Cattaneo-Christov heat flux model. Analysis of heat transfer also incorporates the effects of suction, heat generation and thermal radiation. To showcase the relationship between engineering quantities and pertinent parameters involved in the study, the correlation coefficient for heat transfer coefficient and the skin friction coefficient is computed followed by the computation of probable error and statistical declaration. Similarity transformations are utilized to remodel the constitutive laws of flow in non-dimensional form. Numerical computation of non-linear, coupled O.D.E.’s is performed with the support of the Runge-Kutta-Fehlberg scheme and shooting method. Graphical and tabular illustrations of computed results are provided to report the variation in flow properties with the fluctuation in physical parameters. In both cases, i.e. flow close to a wedge and a cone, the temperature of hybrid nanofluid enhances on intensifying the thermal radiation and experiences a decrement with thermal relaxation parameter and magnetic field. Rising values of the suction parameter, thermal relaxation parameter, and thermal radiation cause increment in heat transfer coefficient. Interestingly, it was spotted that the heat generation parameter has contrary effects on temperature distribution over the two geometries.  相似文献   
35.
29F nucleus is a two-neutron halo nucleus with the core (27F) + n + n three-body system. We studied the Jacobi coordinates dependant T-and Y-configurations properties due to the core deformation of this nucleus. For this deformation of the core, the separation energy (S2n) and the root mean square (RMS) matter radius of this halo nucleus were calculated. This theoretical calculation for investigating T-and Y-configuration properties was accomplished through the MATLAB computational software. A positive core deformation was found, which indicates a prolate shaped halo nucleus. We found an excellent agreement for S2n and 96.4% and 96% accuracies for the T- and Y-configurations respectively.  相似文献   
36.
Hexagonal arrays of gold nanoelements with C3 symmetry are studied as a metamaterial slab of reduced anisotropy. Tri-dimensional (3D) finite-difference time domain (FDTD) simulations are used to calculate the reflected and transmitted electromagnetic field for two waves normally incident to the slab with mutually perpendicular polarizations. S-parameter method is used to retrieve the constitutive parameters for each polarization. While dipolar plasmonic resonance in the case of one layer metamaterial slab leads only to negative values of permittivity, using two layers of asymmetric nanoelements leads to a negative refractive index metamaterial in the near infrared range (158–172 THz) as a result of hybridized plasmonic states inversion.  相似文献   
37.
The attraction towards two-dimensional optical code division multiple access (2D-OCDMA) systems has increased due to its potential in enhancing the performance of optical access networks and producing optical code-based signals. 2D-OCDMA network systems enable better bit-error-ratio (BER) performance as well as increase the number of supportable users in the optical network. Time-spreading wavelength-hopping is one of the many techniques that has been proposed for 2D-OCDMA. In this paper, we present the simulative study of a 2D-OCDMA system. The developed time-spreading, wavelength-hopping network utilizes enhanced double weight (EDW) code which has enhanced properties such as a cross-correlation value of 1 and has a simple encoder/decoder design. The output BER was satisfactory at above 10?9 at data rate of 1.25 Gbps for 20 km distance with the ITU-T G.652 standard single mode optical fiber for 3 users.  相似文献   
38.
The steady laminar boundary layer flow over a permeable flat plate in a uniform free stream, with the bottom surface of the plate is heated by convection from a hot fluid is considered. Similarity solutions for the flow and thermal fields are possible if the mass transpiration rate at the surface and the convective heat transfer from the hot fluid on the lower surface of the plate vary like x−1/2, where x is the distance from the leading edge of the solid surface. The governing partial differential equations are first transformed into ordinary differential equations, before being solved numerically. The effects of the governing parameters on the flow and thermal fields are thoroughly examined and discussed.  相似文献   
39.
Diagonally implicit Runge-Kutta methods satisfying additional order conditions are examined. These conditions make it possible to solve differential algebraic equations of indices two and three to higher accuracy. Advantages of the proposed methods over other known techniques are demonstrated using test problems.  相似文献   
40.
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