301 research outputs found
Improvement of effect of water-in-oil microemulsion as an oral delivery system for fexofenadine: in vitro and in vivo studies
Fexofenadine (FEX) has high solubility and low permeability (BCS, Class III). In this work, novel FEX loaded water in oil microemulsion (w/o) was designed to improve bioavailability and compared with Fexofen® syrup in in vitro and in vivo studies. In addition, pharmacokinetic parameters in permeability studies were estimated by using WinNonLin software program. w/o microemulsion system was optimized using a pseudoternary phase diagram, composed of span 80/lutrol F 68 (9.5:0.5 w/w), oleic acide, isopropyl alcohol and water as surfactant mixture; oil and cosurfactant was developed for oral drug delivery. w/o microemulsion systems were characterized by phase behavior, particle size, viscosity and solubilization capacity. In vitro studies were studied using Caco-2 cell monolayer. Pharmacokinetic parameters of w/o microemulsion were investigated in rabbits and compared to Fexofen® syrup. Fexofen® syrup and microemulsion were administered by oral gavage at 6 mg/kg of the same concentration. The experimental results indicated that microemulsion (HLB = 5.53) formed nanometer sized droplets (33.29 ± 1.76) and had good physical stability. This microemulsion increased the oral bioavailability of FEX which was highly water-soluble but fairly impermeable. The relative bioavailability of FEX microemulsion was about 376.76% compared with commercial syrup in rabbits. In vitro experiments were further employed for the enhanced effect of the microemulsion for FEX. These results suggest that novel w/o microemulsion plays an important role in enhancing oral bioavailability of low permeability drugs
The effect of different packaging materials on proteolysis, sensory scores and gross composition of tulum cheese
In this study, tulum cheese was manufactured using raw ewe’s milk and was ripened in goat’s skin and plastic bags. The effect of ripening materials (skin bag or plastic) on proteolysis was investigated during 120 days of ripening. In addition, sensory scores of the cheeses were assessed at the 90th and 120th days. The gross composition was also determined at the initial stage of ripening. The results showed that, some significant differences were noted between cheeses ripened in goat’s skin and plastic bags in terms of gross composition due to the porous structure of skin bag, which causes moisture loses during ripening. Significant differences were observed in proteolysis indices including water, 12% tricholoroacetic acid and 5% phosphotungstic acid-soluble nitrogen fractions among the cheese samples during ripening. Proteolysis levels were higher in tulum cheeses ripened in goat’s skin.Key words: Tulum cheese, packaging material, sensory analysis, ripening, proteolysis
Absorption enhancement in InGaN-based photonic crystal-implemented solar cells
Cataloged from PDF version of article.We investigate the absorption characteristics of InGaN solar cells with high indium (0.8) content and a one-dimensional periodic nano-scale pattern (implemented) in the InGaN layer theoretically. The short-circuit current of our InGaN-based solar cell structure is calculated for different lattice constant, etch depth, and fill factor values. A substantial increase in the absorption (17.5% increase in short-circuit current) is achieved when the photonic crystal pattern is thoroughly optimized. (c) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JNP.6.061603
In Vitro and In Vivo evaluation of hydroxypropylmethyl cellulose phthalate capsules
The aim of this study was to develop a novel HPMCP capsule. The HPMCP capsule containing99mTc-DTPA and lactose was evaluated in in vitro and in vivo studies. First of all, the HPMCP capsules were prepared and characterized with lenght and diameter size, brittleness facility, moisture content and microbiological test. In vitro resistance and solubility studies of prepared capsules were tested at pH 1.2 and pH 7.4 buffers. The radiolabeled HPMCP capsules were administrated to fasted volunteers. The disintegration times and positions of capsules were recorded by using gamma scintigraphy. In vitro studies showed that HPMCP capsules were gastro resistant for 2 h at pH 1.2 and dissolved at pH 7.4 in 20-25 minutes. The radiolabeled capsules did not disintegrate in stomach whereas disintegrated in intestines. In conclusion, it was found that, the prepared HPMCP capsules can be an alternative to the hard gelatine capsules and used for intestinal targeting.Keywords: Capsule, hydroxypropylmethylcellulose phthalate (HPMCP), gamma scintigraphy, radiolabelling, technetium-99m
Improving the efficiency enhancement of photonic crystal based InGaN solar cell by using a GaN Cap Layer
We studied a high indium content (0.8) InGaN based solar cell design where the active InGaN layer is sandwiched between a GaN cap layer and a GaN spacer layer. The incorporation of the sacrificial cap layer allows for the etching of the front surface without removing the active InGaN resulting in a 50% enhancement of the short-circuit current density for a 15 nm-thick InGaN layer. © 2014 T. F. Gundogdu et al
An intellectual disability syndrome with single nucleotide variants in <i>O-GlcNAc Transferase</i>
Contains fulltext :
220584.pdf (Publisher’s version ) (Open Access)Intellectual disability (ID) is a neurodevelopmental condition that affects ~1% of the world population. In total 5-10% of ID cases are due to variants in genes located on the X chromosome. Recently, variants in OGT have been shown to co-segregate with X-linked intellectual disability (XLID) in multiple families. OGT encodes O-GlcNAc transferase (OGT), an essential enzyme that catalyses O-linked glycosylation with β-N-acetylglucosamine (O-GlcNAc) on serine/threonine residues of thousands of nuclear and cytosolic proteins. In this review, we compile the work from the last few years that clearly delineates a new syndromic form of ID, which we propose to classify as a novel Congenital Disorder of Glycosylation (OGT-CDG). We discuss potential hypotheses for the underpinning molecular mechanism(s) that provide impetus for future research studies geared towards informed interventions
Asymmetric transmission in prisms using structures and materials with isotropic-type dispersion
It is demonstrated that strong asymmetry in transmission can be obtained at the Gaussian beam illumination for a single prism based on a photonic crystal (PhC) with isotropic-type dispersion, as well as for its analog made of a homogeneous material. Asymmetric transmission can be realized with the aid of refraction at a proper orientation of the interfaces and wedges of the prism, whereas neither contribution of higher diffraction orders nor anisotropic-type dispersion is required. Furthermore, incidence toward a prism wedge can be used for one of two opposite directions in order to obtain asymmetry. Thus, asymmetric transmission is a general property of the prism configurations, which can be obtained by using simple geometries and quite conventional materials. The obtained results show that strong asymmetry can be achieved in PhC prisms with (nearly) circular shape of equifrequency dispersion contours, in both cases associated with the index of refraction 0 1. For the comparison purposes, results are also presented for solid uniform nonmagnetic prisms made of a material with the same value of n. It is shown in zero-loss approximation that the PhC prism and the ultralow-index material prism ( 0 1. Possible contributions of scattering on the individual rods and diffraction on the wedge to the resulting mechanism are discussed. Analogs of unidirectional splitting and unidirectional deflection regimes, which are known from the studies of PhC gratings, are obtained in PhC prisms and solid uniform prisms, i.e. without higher diffraction orders. ©2015 Optical Society of America
Sparse representation of two- and three-dimensional images with fractional Fourier, Hartley, linear canonical, and Haar wavelet transforms
Sparse recovery aims to reconstruct signals that are sparse in a linear transform domain from a heavily underdetermined set of measurements. The success of sparse recovery relies critically on the knowledge of transform domains that give compressible representations of the signal of interest. Here we consider two- and three-dimensional images, and investigate various multi-dimensional transforms in terms of the compressibility of the resultant coefficients. Specifically, we compare the fractional Fourier (FRT) and linear canonical transforms (LCT), which are generalized versions of the Fourier transform (FT), as well as Hartley and simplified fractional Hartley transforms, which differ from corresponding Fourier transforms in that they produce real outputs for real inputs. We also examine a cascade approach to improve transform-domain sparsity, where the Haar wavelet transform is applied following an initial Hartley transform. To compare the various methods, images are recovered from a subset of coefficients in the respective transform domains. The number of coefficients that are retained in the subset are varied systematically to examine the level of signal sparsity in each transform domain. Recovery performance is assessed via the structural similarity index (SSIM) and mean squared error (MSE) in reference to original images. Our analyses show that FRT and LCT transform yield the most sparse representations among the tested transforms as dictated by the improved quality of the recovered images. Furthermore, the cascade approach improves transform-domain sparsity among techniques applied on small image patches. © 2017 Elsevier Lt
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