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991.
J. Á. García Hernández D. Madera González M. Padilla Castillo T. Figueras Falcón 《International journal of cosmetic science》2013,35(3):233-237
Few studies have tested the efficacy of commercially available cosmetic products for preventing striae gravidarum. Therefore, the objective of this study was to evaluate efficacy on prevention of striae gravidarum using a specific anti‐stretch mark cream containing hydroxyprolisilane‐C, rosehip oil, Centella asiatica triterpenes and vitamin E. A randomized, double‐blind, placebo‐controlled trial was conducted between November 2009 and April 2011. Pregnant women were included and classified as treated group (emollient and moisturizer containing hydroxyprolisilane C, rosehip oil, Centella asiatica triterpenes and vitamin E) and control group (cream without the active ingredients). Overall incidence of stretch marks during pregnancy was 33.3% for the control group and 37.6% for the treated group (n.s.). Severity of previous stretch marks significantly increased in the control group during the study (17.8%, P = 0.001), but not in the treated group (6.3%, ns). In women who developed new stretch marks during the study, there was a significantly greater ‘difference in severity’ (between baseline and maximum severity) in control group vs. treated group (0.47 [0.57] vs. 0.14 [0.60], P = 0.031). In women without previous striae, incidence of these marks was significantly lower for the treated group patients compared with control group (5.6% vs. 35%, P = 0.031, OR: 9.2 [95% CI: 1.0–83.3]). The use of the anti‐stretch mark product is proved to be effective in reducing severity of the striae during pregnancy, prevents the appearance of new striae and halts progression of those already present. In women who had no striae at baseline, use of the anti‐stretch mark cream was more effective than placebo in preventing new stretch marks. 相似文献
992.
Viscoelastic and morphological properties of functionalized‐polymer‐modified asphalt, FPMA, have been described as function of number of epoxy groups presented in the functionalized polymer. At low temperatures, simple viscoelastic models can predict the elastic response of FPMA at short times and its viscous behavior at long times. The increase of epoxy groups yielded an increase on activation energy for viscous deformation of FPMA, and so, on its resistance to irreversible deformations under strain cycles. From ambient to higher temperatures, emulsion model can predict rheological properties of FPMA because they behave as viscoelastic emulsions. Modification of relaxation spectrum for FPMA due to the presence of a polymer network was not as strong as in normal PMA, thus, the rheological behavior of FPMA was found similar to systems having weak networks. However, the network became stronger as the number of epoxy groups was increased. This trend was verified by morphology of FPMA. Emulsion‐like structure was observed for all FPMA but differentiating each other by the polymer particle size. It was also observed that increase on epoxy groups, polymer particle size in the FPMA decreased, and higher stability at 180°C of FPMA was observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
993.
Marta Diez-Valcarce Katarina Kovač Nigel Cook David Rodríguez-Lázaro Marta Hernández 《Food Analytical Methods》2011,4(3):437-445
Internal amplification controls (IACs) were constructed for incorporation into real-time nucleic acid amplification assays
for bovine polyomavirus, hepatitis A virus, hepatitis E virus, human adenovirus, human norovirus genogroup I, human norovirus
genogroup II, murine norovirus and porcine adenovirus. The addition of optimised amounts of IAC into the assays did not affect
the limits of detection for each specific target virus. A poorly performed extraction of viral nucleic acids was simulated,
and the effectiveness of IACs in identifying failed assays was demonstrated. The IACs constructed in this study can be reliably
used in their specific assays to provide a robust control that can be routinely applied in the analysis of foods for viruses. 相似文献
994.
M. Hernández-Hernández W. Cruz-Mendez C. González-Rivera 《Materials and Manufacturing Processes》2015,30(2):216-221
Mathematical and physical models of water deoxidation in a batch aluminum degassing reactor using the rotor-injector technique were developed. The mathematical model was successfully validated against measured degassing kinetics. The physical model was employed to perform a process analysis using a two-level factorial experimental design to determine the influence of gas flow rate, impeller angular velocity, and gas injection points on gas consumption efficiency and degassing kinetics. A combination of higher rotor speeds and gas flow rates results in fast degassing kinetics. However, moderate gas flow rates are recommended to save gas. 相似文献
995.
MoVTeNb mixed oxides catalysts have been prepared by a slurry method with different molar compositions (Mo/Te ratio from 2 to 6 and Nb/(V + Nb) ratio from 0 to 0.7) in the synthesis gel leading to different crystalline phases distribution and catalytic behaviour in the partial oxidation of both propane and propylene to acrylic acid. Chemical analysis indicates that the composition of samples before and after the heat-treatment changes, especially the Te-content, since a significant amount of Te is lost during the heat-treatment step when the amount of oxalate (from niobium oxalate) increases in the synthesis gel. Thus, the nature of the crystalline phases and the catalytic performance of heat-treated materials will be related to the final chemical composition. On the other hand, only the catalysts presenting Te2M20O57 (M = Mo, V, Nb) crystalline structure, the so-called M1 phase, were active and selective in the partial oxidation of propane to acrylic acid. Moreover, all catalysts were active and relatively selective to the formation of O-containing products, i.e. acrolein and/or acrylic acid, during the partial propylene oxidation although the more active ones were those presenting M1 phase. 相似文献
996.
L. May‐Hernández F. Hernández‐Sánchez J. L. Gomez‐Ribelles R. Sabater‐i Serra 《应用聚合物科学杂志》2011,119(4):2093-2104
A series of segmented poly(urethane‐urea) polymers have been synthesized varying the hard segments content, based on the combination of polycaprolactone diol and aliphatic diisocyanate (Bis(4‐isocyanatocyclohexyl)methane), using diamine (1,4‐Butylenediamine) as the chain extender. The microstructure and properties of the material highly depend on the hard segments content (from 14 to 40%). These PUUs with hard segment content above 23% have elastomeric behaviors that allow high recoverable deformation. The chemical structure and hydrogen bonding interactions were studied using FTIR and atomic force microscopy, which revealed phase separation that was also confirmed by DSC, dynamic‐mechanical, and dielectric spectroscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
997.
Native and modified chayotextle flour effect on functional property and cooking quality of spaghetti
Sara M. Chavarría-Fernández J. De J. Berrios James L. Pan Priscila L.S. Alves Heidi M. Palma-Rodriguez Juan P. Hernández Uribe Alejandro Aparicio-Saguilan Apolonio Vargas-Torres 《International Journal of Food Science & Technology》2021,56(9):4516-4525
The objective of this research was to study the effect of partially substituting semolina flour by native (NCHF) and modified chayotextle (CHFMD) flours, on the physicochemical properties and cooking quality of spaghetti. Spaghetti was obtained by replacing semolina flour (control) with five different concentrations of NCHF and CHFMD flours (10%, 17.5%, 25%, 32.5% and 40%). The proximal composition of the flours showed that both NCHF and CHFMD flours lower content of protein and fat but higher content of ash and resistant starch (RS). Moreover, the RS content increased due to thermal modification (TM) and that RS remained high, even after the cooking process. Pasting properties such as peak viscosity, breakdown, setback and final viscosity were influenced by NCHF and CHFMD concentrations. Brightness (ΔL*) was significantly reduced by inclusion of increasing CHFMD levels. True density and water absorption values increased with addition of NCHF and CHFMD, compared to the control spaghetti. The results obtained in this study demonstrated the possibility for producing spaghetti containing up to 40% CHFMD flour, with acceptable quality and functional properties. 相似文献
998.
R. Quintana-Sol��rzano A. Rodr��guez Hern��ndez R. Garc��a-de-Le��n E. Terr��s 《Topics in Catalysis》2011,54(8-9):547-560
Besides offering an adequate product distributions, a cracking catalyst must exhibit a reasonable resistance to the combined effect of high temperature, steam and metals. Two commercial catalysts, poisoned with Ni + V (~2,500 ppm), are subjected to a large scale cyclic deactivation with steam, then characterized using mostly basic techniques and finally tested via bench scale and pilot scale cracking experiments. As examples of industrial deactivation, corresponding equilibrium catalysts (E-CATs) are investigated in parallel. Depending on their specific formulation, catalysts deactivate differently due to the exposition to high temperature steam and metals. The intrinsic deviations in the catalytic properties of cyclic deactivated catalysts (CD-CATs) related to E-CATs are further biases by the particular history of the latter and the particular reactor configuration and hydrodynamics, such deviations being magnified in the bench scale testing. Relative differences in activity and product yields (except for coke and hydrogen) of CD-CATs referred to E-CATs are below 10% at the pilot scale, and within 23% at the bench scale. Relative biases in hydrogen and coke yield of may be as high as 75 and 26% in the pilot plant and as much as 150 and 32% at the bench scale. 相似文献
999.
Gaxiola Hernández Alberto Ossa López Alexandra 《Mechanics of Time-Dependent Materials》2019,23(3):267-281
Mechanics of Time-Dependent Materials - Embankment dams with asphalt concrete cores have been constructed on practically all continents with satisfactory results. Nowadays many advantages, such as... 相似文献
1000.
Liliana Maribel Perez-Perez José Ángel Huerta-Ocampo José Rogelio Ramos-Enríquez Saúl Ruiz-Cruz Francisco Javier Wong-Corral Ema Carina Rosas-Burgos Magdalena Hernández-Ortíz Sergio Encarnación-Guevara Miguel Angel Robles-García Rey David Iturralde-García Jesús Borboa-Flores Carmen Lizette Del-Toro-Sánchez 《International Journal of Food Science & Technology》2021,56(12):6497-6506
The objective of this work was to release bound phenolic compounds (PC) from chickpea by the interaction of the microbiota of a volunteer and to identify the enzymes implied to deliver these PC. The highest amount of PC was released at 12 and 24 h (16.8–18.5 mg GAE/g). Higher antioxidant capacity was observed in these hours through 2,20-azino-bis-(3ethylbenzothiazoline-6-sulfonic acid), 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power and 2,´2.Azobis (2 methylpropionamidine) techniques. Escherichia, Klebsiella, Bacteroides and Veillonella were some genera identified in the microbiota implied in delivered PC. The principal PC identified by ultra performance liquid chromatography–mass spectrometry were flavonoids. Proteomic analysis identified hundreds of proteins from the intestinal microbiota after 12 h of fermentation, including enzymes related to the release of bound PC from chickpea such as pectin esterase. Therefore, this enzyme could be used in other food sources for the release of PC bound to the food matrix and thus take advantage of their bioactive benefits. 相似文献