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171.
Mahmoud H. Teaima Sally A. Abdelhalim Mohamed A. El-Nabarawi Dalia A. Attia Doaa A. Helal 《Drug development and industrial pharmacy》2018,44(1):158-171
Cellulite is a common topographical alteration where skin acquires an orange peel or mattress appearance with alterations in adipose tissue and microcirculation. This work aims to develop and evaluate a topical niosomal gel formulae with good permeation to reach the subcutaneous fat layer. Several caffeine niosomal dispersions were prepared and incorporated into gel formulae using Carbopol 940 polymer, chemical penetration enhancers, and iontophoresis, then the prepared gels were applied onto the skin of rats and anticellulite activity of caffeine from the prepared gels compared to that of the commercial product Cellu Destock® was evaluated by histological study of the skin and measurement of plasma level of caffeine passing through the skin using liquid chromatography (LC/MS–MS). Results of histology revealed reduction of size and thickness of fatty layer of rat skin in the following order: FVII?>?FXIV?>?Cellu Destock®?>?FVII?+?Iontophoresis?>?FXIV?+?Iontophoresis. Pharmacokinetic results of caffeine in plasma revealed that Cmax, Tmax, and AUC0–12h decreased in the following order: FXIV?>?FVII?>?Cellu Destock®. These results conclude that incorporation of caffeine niosomal dispersion into gel matrix with penetration enhancers and iontophoresis resulted in improvement in penetration of caffeine through the skin into the underlying fatty layer in treatment of cellulite. 相似文献
172.
173.
Dalia Streimikiene 《Renewable & Sustainable Energy Reviews》2012,16(5):2434-2445
Nuclear power and carbon capture and storage (CCS) are key greenhouse gas mitigation options under consideration across the world. Both technologies imply long-term waste management challenge. Geological storage of carbon dioxide (CO2) and nuclear waste has much in common, and valuable lessons can be learnt from a comparison. Seeking to compare these technologies economic, social and environmental criteria need to be selected and expressed in terms of indicators. Very important issue is costs and economics of geological storage of carbon dioxide and nuclear waste. The costs of storage are one of the main indicators for assessment of technologies in terms of economic criteria.The paper defines the costs of the geological storage of CO2 and nuclear waste in Lithuania, drawing also on insights from other parts of the world. The costs of carbon dioxide and nuclear waste storage are evaluated in UScnt/kWh and compared. The paper critically compares the characteristics and location of the both sources of and storage options for CO2 and nuclear waste in Lithuania. It discusses the main costs categories for carbon dioxide and nuclear waste storage. The full range of potential geological storage options is considered and the most reliable options for carbon dioxide and nuclear waste are selected for the comparative costs assessment. 相似文献
174.
AlAli Moneera AlQahtani Maram AlJuried Azizah Taghareed AlOnizan Dalia Alboqaytah Nida Aslam Irfan Ullah Khan 《计算机、材料和连续体(英文)》2021,66(2):1681-1696
Online advertisements have a significant influence over the success or failure of your business. Therefore, it is important to somehow measure the impact of your advertisement before uploading it online, and this is can be done by calculating the Click Through Rate (CTR). Unfortunately, this method is not eco-friendly, since you have to gather the clicks from users then compute the CTR. This is where CTR prediction come in handy. Advertisement CTR prediction relies on the users’ log regarding click information data. Accurate prediction of CTR is a challenging and critical process for e-advertising platforms these days. CTR prediction uses machine learning techniques to determine how much the online advertisement has been clicked by a potential client: The more clicks, the more successful the ad is. In this study we develop a machine learning based click through rate prediction model. The proposed study defines a model that generates accurate results with low computational power consumption. We used four classification techniques, namely K Nearest Neighbor (KNN), Logistic Regression, Random Forest, and Extreme Gradient Boosting (XGBoost). The study was performed on the Click-Through Rate Prediction Competition Dataset. It is a click-through data that is ordered chronologically and was collected over 10 days. Experimental results reveal that XGBoost produced ROC-AUC of 0.76 with reduced number of features. 相似文献
175.
Carvalho AT Maia AC Ojima PY dos Santos AA Schlindwein C 《Journal of chemical ecology》2012,38(3):315-318
Flower localization in darkness is a challenging task for nocturnal pollinators. Floral scents often play a crucial role in
guiding them towards their hosts. Using common volatile compounds of floral scents, we trapped female nocturnal Megalopta-bees (Halictidae), thus uncovering olfactory cues involved in their search for floral resources. Applying a new sampling
method hereby described, we offer novel perspectives on the investigation of nocturnal bees. 相似文献
176.
de Moura LP Kalva-Filho CA Loures JP de Sousa Silva M Zorzetto LP Junior MC de Araújo MB Dalia RA de Mello MA 《Journal of the International Society of Sports Nutrition》2012,9(1):10-7
Background
The influence of feed restriction and different diet's caloric value on the aerobic and anaerobic capacity is unclear in the literature. Thus, the objectives of this study were to determine the possible influences of two diets with different caloric values and the influence of feed restriction on the aerobic (anaerobic threshold: AT) and anaerobic (time to exhaustion: Tlim) variables measured by a lactate minimum test (LM) in rats.Methods
We used 40 adult Wistar rats. The animals were divided into four groups: ad libitum commercial Purina? diet (3028.0 Kcal/kg) (ALP), restricted commercial Purina? diet (RAP), ad libitum semi-purified AIN-93 diet (3802.7 Kcal/kg) (ALD) and restricted semi-purified AIN-93 diet (RAD). The animals performed LM at the end of the experiment, 48 h before euthanasia. Comparisons between groups were performed by analysis of variance (p < 0,05).Results
At the end of the experiment, the weights of the rats in the groups with the restricted diets were significantly lower than those in the groups with ad libitum diet intakes. In addition, the ALD group had higher amounts of adipose tissue. With respect to energetic substrates, the groups subjected to diet restriction had significantly higher levels of liver and muscle glycogen. There were no differences between the groups with respect to AT; however, the ALD group had lower lactatemia at the AT intensity and higher Tlim than the other groups.Conclusions
We conclude that dietary restriction induces changes in energetic substrates and that ad libitum intake of a semi-purified AIN-93 diet results in an increase in adipose tissue, likely reducing the density of the animals in water and favouring their performance during the swimming exercises. 相似文献177.
Dr. Mathew Sutherland Alice Li Anissa Kaghad Dimitrios Panagopoulos Dr. Fengling Li Dr. Magdalena Szewczyk Dr. David Smil Dr. Cora Scholten Dr. Léa Bouché Dr. Timo Stellfeld Dr. Cheryl H. Arrowsmith Dr. Dalia Barsyte Dr. Masoud Vedadi Dr. Ingo V. Hartung Dr. Holger Steuber Dr. Robert Britton Dr. Vijayaratnam Santhakumar 《ChemMedChem》2021,16(7):1116-1125
Protein arginine N-methyl transferase 4 (PRMT4) asymmetrically dimethylates the arginine residues of histone H3 and nonhistone proteins. The overexpression of PRMT4 in several cancers has stimulated interest in the discovery of inhibitors as biological tools and, potentially, therapeutics. Although several PRMT4 inhibitors have been reported, most display poor selectivity against other members of the PRMT family of methyl transferases. Herein, we report the structure-based design of a new class of alanine-containing 3-arylindoles as potent and selective PRMT4 inhibitors, and describe key structure–activity relationships for this class of compounds. 相似文献
178.
Dalia Emam Mohamed Nabel A. Negm Marwa R. Mishrif 《Journal of surfactants and detergents》2013,16(5):723-731
The interfacial and micellization behaviors of binary mixtures of two gemini cationic surfactants and conventional the cetyl trimethyl ammonium bromide surfactant were studied at various molar ratios. From the equilibrium surface tension measurements, the critical micelle concentrations (CMC) data were obtained as functions of the composition. Values of the CMC were analyzed according to the regular solution model developed by Rubingh for mixed micelles. Two interaction parameters were obtained for each system, the interaction at the interface, and in the micellar phase. The results showed that micellization and adsorption properties of the studied mixed systems depend on the spacer chain lengths of the gemini surfactants and their ratio in the mixed systems. 相似文献
179.
Nabel A. Negm Ahmed F. M. El Farargy Dalia Emam Mohammed Haytham N. Mohamad 《Journal of surfactants and detergents》2012,15(4):433-443
In order to discover new and safe surfactants with regard to the environment, new environmentally friendly nonionic surface active agents were synthesized by the reaction of tannic acid (as a natural product presents in several plants) and polyethylene glycol fatty acids containing different numbers of ethylene glycol units. The fatty acids were dodecanoic, hexadecanoic, octadecanoic and oleic acids. The chemical structures of the synthesized surfactants were confirmed using elemental analysis, infrared and 1H-NMR spectroscopy. The molecular weights of the synthesized surfactants were determined using viscosity measurements and gel permeation chromatography. The surface properties of these surfactants were determined using surface tension measurements. The chemical structure?Csurface activity relationship of these surfactants showed a strong dependence of the surface activity on their chemical structures including the hydrophobic chains and the number of ethylene glycol units incorporated in the molecules. The free energy of micellization of the surfactants in their solutions showed their tendency towards micellization in the bulk of their solutions, while the free energy of adsorption showed their high tendency towards adsorption at the air?Cwater interface. 相似文献
180.
Based on the poudretteite (K Na2 B3 Si12 O30) glass composition, six transparent glass frits were prepared. TiO2, LiF and Cr2O3 were experimented on the base glass composition as nucleation catalysts. Only cristobalite and tridymite were developed through the sintering process of the glasses between 900 and 1100?°C. LiF enhances mainly tridymite with traces of cristobalite and in the opposite side the parent and both TiO2 and Cr2O3 containing glasses catalyzed mainly cristobalite with traces of tridymite. The microstructure of the glass samples heat-treated at 1000?°C showed backbone-like, small rods, quadrant-, hexagonal crystals referred to the cristobalite and tridymite. The EDS microanalysis shows the presence of both alkalis, i.e. Na?+? and K?+?, in the cristobalite crystal structure while the residual glass contains K?+?. The infrared spectroscopy indicates the band patterns of cristobalite and tridymite. 相似文献