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21.
This research deals with the production of water‐soluble polysaccharides from six polysaccharide‐producing Penicillium species. Eup. pinetorum ATCC 14770 was promising for exo‐ and endopolysaccharides production under various cultural conditions. pH 5.0, 7 days, and pH 8.0, 10 days, were the optimum for the production of exo‐ and endopolysaccharides, respectively, at 30 °C in medium containing glucose and peptone. HPLC results revealed that both polysaccharides were composed of pectin, cellulose and hemicellulose. Exopolysaccharides produced by Eup. pinetorum was subjected to evaluation as a natural flavour stabiliser in cloudy apple juice (CAJ). Twenty‐one volatile compounds classified into esters, aldehydes, alcohols and ketone were detected, only eighteen compounds of which were characterised by their odours threshold. The esters and alcohols are accounting for 87.64% and 5.44% of total volatiles, respectively. This study indicates that the use of exopolysaccharides as an alternative flavour stabiliser in CAJ is very promising.  相似文献   
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An adamantane‐based atom transfer radical initiator (Adm‐Br) was prepared by the treatment of 1‐[[N‐[2‐Hydroxy‐l,l‐bis(hydroxymethyl)ethyl]amino]carbonyl]adamantane with bromopropionyl bromide. The resulting initiator was subsequently used in the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) to form (Adm‐p‐MMA), which was successfully used, as a macroinitiator, in further ATRP reactions with 3‐O‐methacryloyl‐1,2 5,6‐di‐O‐isopropylidene‐α‐d ‐glucofuranose (gly), a glycomonomer, to afford the Adm‐p‐MMA‐b‐gly polymer. The new Adm‐p‐MMA‐b‐gly polymer subsequently was employed to form a nanocomposite with chitosan‐modified, Nanofil clay (NC). The resulting Adm‐p‐MMA‐b‐gly/NC composite material was progressively hydrolyzed to regenerate the OH groups of the glucose units within the Adm‐p‐MMA‐b‐gly copolymer. The polymer/NC nanocomposites were characterized by X‐ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, and transmission electron microscopy. POLYM. ENG. SCI., 54:2669–2675, 2014. © 2013 Society of Plastics Engineers  相似文献   
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In reliability analysis, the stress-strength model is often used to describe the life of a component which has a random strength (X) and is subjected to a random stress (Y). In this paper, we considered the problem of estimating the reliability R=P [Y<X] when the distributions of both stress and strength are independent and follow exponentiated Pareto distribution. The maximum likelihood estimator of the stress strength reliability is calculatedunder simple random sample, ranked set sampling and median ranked set sampling methods. Four different reliability estimators under median ranked set sampling are derived. Two estimators are obtained when both strength and stress have an odd or an even set size. The two other estimators are obtained when the strength has an odd size and the stress has an even set size and vice versa. The performances of the suggested estimators are compared with their competitors under simple random sample via a simulation study. The simulation study revealed that the stress strength reliability estimates based on ranked set sampling and median ranked set sampling are more efficient than their competitors via simple random sample. In general, the stress strength reliability estimates based on median ranked set sampling are smaller than the corresponding estimates under ranked set sampling and simple random sample methods.  相似文献   
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Enhancement of the dissolution rate of the poorly water-soluble hypoglycemic agent, gliclazide, by the aid of lyophilization was investigated. Mannitol, sodium lauryl sulfate (SLS) and polyvinyl pyrrolidone (PVP-k-30) were employed in different weight ratios (43%, 56% and 64% w/w, respectively) as water-soluble excipients in the formulation. Lyophilized systems were found to exhibit extremely higher in vitro dissolution rate compared to the unprocessed drug powder. Solid state characterization of the lyophilized systems using X-ray powder diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry techniques revealed that dissolution enhancement was attributable to transformation of gliclazide from the crystalline to an amorphous state in the solid dispersion formed during the lyophilization process. The gastrointestinal absorption and hypoglycemic effect of the lyophilized gliclazide/SLS system were investigated following oral administration to Albino rabbits. Cmax and area under the plasma concentration–time curve of gliclazide (AUC0–12) after administration of the lyophilized formulations were significantly higher than those obtained after administration of the unprocessed gliclazide.  相似文献   
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Local delivery of antibiotics has been shown to be effective in reducing periodontopathic microorganisms. The purpose of this study is to formulate gels containing secnidazole or doxycycline hydrochloride that could be used in the treatment of periodontitis by direct periodontal intrapocket administration. Different mucoadhesive polymers were used as cellulose derivatives, carbopol and eudragit. The prepared gels were evaluated for their in vitro drug release, rheological behavior, and mucoadhesive force. Increasing the concentration of each polymer increased the viscosity, mucoadhesion, and the time required for 30 and 50% release of the original mass of each drug. Gels with appropriate balance of the above-examined parameters were selected for microbiological evaluation. Microbiological studies on selected gels showed faster release of the two drugs (expressed as inhibition zones) than the commercial products of chlorhexidine gel (Eluge and miconazole nitrate emulgel (Miconaz).  相似文献   
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Cyberbullying (CB) is a challenging issue in social media and it becomes important to effectively identify the occurrence of CB. The recently developed deep learning (DL) models pave the way to design CB classifier models with maximum performance. At the same time, optimal hyperparameter tuning process plays a vital role to enhance overall results. This study introduces a Teacher Learning Genetic Optimization with Deep Learning Enabled Cyberbullying Classification (TLGODL-CBC) model in Social Media. The proposed TLGODL-CBC model intends to identify the existence and non-existence of CB in social media context. Initially, the input data is cleaned and pre-processed to make it compatible for further processing. Followed by, independent recurrent autoencoder (IRAE) model is utilized for the recognition and classification of CBs. Finally, the TLGO algorithm is used to optimally adjust the parameters related to the IRAE model and shows the novelty of the work. To assuring the improved outcomes of the TLGODL-CBC approach, a wide range of simulations are executed and the outcomes are investigated under several aspects. The simulation outcomes make sure the improvements of the TLGODL-CBC model over recent approaches.  相似文献   
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This paper describes the results and implications of a study into the effectiveness of a blended e-learning cooperative approach (BeLCA) on Pre-Service Teacher’s (PST) achievement, attitudes towards e-learning and cooperativeness. Quantitative and qualitative methodologies were used with participants of the study. Twenty-six science PSTs, enrolled in an Egyptian university, represented the study’s experiential and control groups. Pre and post-tools were administered to participants in the two groups in a quasiexperimental design. Instruments to measure dependent variables of the study were developed by the authors in light of relevant previous studies.  相似文献   
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Multimedia Tools and Applications - In this era of technology, digital images turn out to be ubiquitous in a contemporary society and they can be generated and manipulated by a wide variety of...  相似文献   
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