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51.
We report the effects of the thermal annealing and dopant concentration on the optical properties of Se or S-doped hydrogenated amorphous silicon thin films. The Se and S-doped a-Si:H (a-Si,Se:H and a-Si,S:H) thin films were prepared by glow discharge plasma enhanced chemical vapor deposition (GD-PECVD) on 7059 corning glass. The films were subsequently annealed in vacuum in the temperature range from 100 to 500 °C. Influence of doping and annealing was examined by means of optical transmission spectroscopy of the films in the wavelength range of 300-1100 nm taken at room temperature. The absorption coefficients and refractive indices decreased as the annealing temperature increased from 100 to 300 °C and then increased again as the annealing temperature further increased to 500 °C, while the highest bandgap was observed at 300 °C for all of the samples. For a given dopant concentration bandgap was observed to be higher in a-Si,S:H than a-Si,Se:H thin films.  相似文献   
52.
Context: The vesicles based on skin lipid have a drug localization effect and its main lipid, ceramide provides protective and regenerative effects while oleic acid (OA) is a penetration enhancer, however, it causes slight irritation, so we have formulated formulation incorporating both of these to develop a transdermal formulation for better permeation.

Objective: Present study investigated the preparation and characterization of physicochemical properties and permeation of nanovesicles of ceramide-2 containing OA and palmitic acid (PA) respectively and a commercial gel.

Materials and methods: The vesicles were made using ceramide 2, cholesterol (Chol), cholesteryl sulfate (CS) and OA or PA, respectively, using film hydration method. The vesicles were characterized for physicochemical properties, ex vivo permeation using human skin and pharmacokinetic parameters and anti-inflammatory activity in rats.

Results: The vesicles showed size at 102–125?nm while PDI was 0.11–0.13 and negative zeta potential. OV-3 showed highest entrapment efficiency. The drug fluxes were 92.02 and 8.920?μg/cm2/h, respectively, for OV-3 and PV-1. The Cmax were 7.91 and 4.01?μg/ml at 4 and 6?h for OV-3 (2.5?mg) and PV-1 (10?mg), respectively. OV-3 and PV-1 showed 98.8% and 77.36% edema inhibition, respectively, at 3?h.

Discussion: Both formulations showed similar physical parameters and different permeation since OA get incorporated in vesicles and increases its permeability and ceramide makes sure that vesicles can rapidly traverse the stratum corneum.

Conclusion: OV-3 containing 3% OA showed optimum physical parameters and good permeation with maximum anti-inflammatory activity.  相似文献   
53.
It is now generally accepted that 16S and 23S ribosomal RNA play important roles in the decoding and peptidyl transferase activities of ribosomes. Despite their complex structures and numerous associated proteins it is possible that small domains of these rRNAs can fold and function autonomously, particularly those that appear devoid of protein interactions. One candidate for such a domain is the decoding region, located near the 3' end of 16S rRNA (Fig. 1a, b). Consistent with this hypothesis, aminoglycoside antibiotics that interact with the decoding region in 30S subunits interact with other RNAs in the absence of proteins. In addition, certain activities of self-splicing introns, at least superficially, resemble translational decoding. We report here that an oligoribonucleotide analogue of the decoding region interacts with both antibiotic and RNA ligands of the 30S subunit in a manner that correlates with normal subunit function. The activities of the decoding region analogue suggest that the intimidating structural complexity of the ribosome can be, to some degree, circumvented.  相似文献   
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Using the past diffusion trends of four renewable energy technologies for irrigation water pumping in India (SPV pumps, windmill pumps and biogas/producer gas driven dual fuel engine pumps), results of an attempt to project their future dissemination levels, have been presented in this study. The likely contribution of the renewable energy options considered in the study to the projected energy demand for irrigation water pumping in India has been estimated. Estimates of the associated investment requirements taking into account the learning effect have also been presented.  相似文献   
57.
In the present paper, the melting heat transfer of a nanofluid over a stretching sheet is investigated. Magnetohydrodynamic stagnation point flow with thermal radiation and slip effects is considered for this study. The governing model of the flow is solved by Runge–Kutta fourth-order method using appropriate similarity transformations. Temperature and velocity fields are presented for various flow pertinent parameters. Nondimensional physical parameters such as Prandtl number, radiation parameter, Brownian motion parameter, Lewis number, thermophoresis parameter, magnetic parameter, and melting parameter on fluid velocity, heat, concentration, skin friction, Sherwood number, and Nusselt number are presented graphically and discussed numerically. Heat transfer rate can be increased by increasing slip, melting, or radiation parameter. Mass transfer increases for greater values of melting parameter or slip parameter while radiation parameter shows the opposite impact on mass transfer.  相似文献   
58.
The design and synthesis of a series of bicyclic ring containing dual aromatase–sulfatase inhibitors (DASIs) based on the aromatase inhibitor (AI) 4‐[(4‐bromobenzyl)(4H‐1,2,4‐triazol‐4‐yl)amino]benzonitrile are reported. Biological evaluation with JEG‐3 cells revealed structure–activity relationships. The X‐ray crystal structure of sulfamate 23 was determined, and selected compounds were docked into the aromatase and steroid sulfatase (STS) crystal structures. In the sulfamate‐containing series, compounds containing a naphthalene ring are both the most potent AI ( 39 , IC50 AROM=0.25 nM ) and the best STS inhibitor ( 31 , IC50 STS=26 nM ). The most promising DASI is 39 (IC50 AROM=0.25 nM , IC50 STS=205 nM ), and this was evaluated orally in vivo at 10 mg kg?1, showing potent inhibition of aromatase (93 %) and STS (93 %) after 3 h. Potent aromatase and STS inhibition can thus be achieved with a DASI containing a bicyclic ring system; development of such a DASI could provide an attractive new option for the treatment of hormone‐dependent breast cancer.  相似文献   
59.
The objective of this research was to evaluate the rheological, sensorial, and chemopreventive properties of milk fermented with different exopolysaccharide (EPS)-producing lactic cultures. Reconstituted skim milk (11% wt/vol) was fermented with single strains of EPS-producing and non-EPS-producing cultures. Whey that collected on the surface of undisturbed fermented milks and after cutting was measured. All EPS-producing cultures reduced the amount of whey present on the surface of the undisturbed samples, whereas only 3 out of 5 strains reduced syneresis measured after cutting. All EPS-producing cultures except a strain of Lactobacillus delbrueckii ssp. bulgaricus reduced viscoelastic moduli in fermented milk. There was a linear correlation between ropiness and smoothness. In the chemoprevention study, 140 male Fisher rats were divided into 7 groups of 20 each. Rats in 6 groups were fed diets supplemented with fermented milks each made with a single strain of EPS-producing or non-producing cultures, whereas rats in group 7 (control) were fed a diet supplemented with milk acidified with glucono-δ-lactone (GDL). All rats were injected with azoxymethane (15 mg/kg, subcutaneous) at wk 7 and 8 of age to induce tumors and fed their respective diets ad libitum throughout the study. After 30 wk of initiation, all rats were anesthetized with ether, and their intestinal tissues were isolated and washed with cold normal saline. The number and size of tumors in the colon and small intestine were recorded. Rats fed diets supplemented with fermented milk made with 2 EPS-positive and 1 EPS-negative strains had significantly lowered incidence of colon tumor and colon tumor multiplicity. Cyclooxygenase-2 enzyme activity (the enzyme implicated in colon tumor development) was significantly lower in the colon tissue of rats fed diets containing milk fermented with 4 EPS-producing and 1 non-producing cultures than that in rats fed diets supplemented with GDL-acidified milk. Different EPS-positive cultures produced fermented milks with distinct rheological characteristics and levels of ropiness. No relationship was found between rheological properties or level of ropiness of fermented milk and its chemopreventive effect.  相似文献   
60.
Smart Manufacturing (SM) a revolutionary paradigm that aims to improve production systems’ performance in terms of quality, time, cost, and flexibility, as well as human and machine decision-making capabilities. Most large enterprises have already taken first steps towards adopting SM. Small and Medium-sized Enterprises (SMEs) on the other hand, are struggling with developing a SM adoption roadmap. Our research builds on the real and perceived needs and challenges faced by manufacturing SMEs and advances the field by developing and evaluating an SME-specific ‘SM adoption framework’. We have employed a multiple case study approach to acknowledge the lessons learned by selected early-adopter SMEs that have recently implemented and deployed SM tools and practices. We propose an SM adoption framework with five vital steps that SMEs interested in SM should follow: (i) identify manufacturing data available within the SME, (ii) readiness assessment of the SME data-hierarchy steps, (iii) developing SM awareness of SME leadership and staff, (iv) develop a SM tailored vision for the SMEs, and (v) identify appropriate SM tools and practices necessary to realise the tailored SM vision. Moreover, the results of the case study analysis enabled us to formulate many generalisations.  相似文献   
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