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101.
Violeta T. Pardio Krzysztof N. Waliszewski Argel Flores 《International Journal of Food Science & Technology》2010,45(2):344-347
The effects of enzyme assisted vanilla extract (EAVE), traditional vanilla extract made from the same mature vanilla beans and commercial vanilla extract, adjusted to 0.1% vanillin concentration, on the sensory and colour properties of vanilla ice cream were studied. For the production of 1 kg of ice cream, vanilla extracts contributed 5 mg of vanillin but each extract contributed different amounts of non‐vanillin flavour compounds. Flavour and odour parameters of ice creams did not show changes during 3 weeks of storage while colour parameters decreased in ice cream made with EAVE from the first day of manufacture. When EAVE was used, it produced a whiter colour in the ice cream, which was found to be less stable from the second week of storage. This observation was confirmed with the measurement of L and chroma colour parameters. 相似文献
102.
Madalina Dumitrescu Ana Maria Vacaru Violeta Georgeta Trusca Ioana Madalina Fenyo Radu Ionita Anca Violeta Gafencu 《International journal of molecular sciences》2021,22(2)
Adenoviral vectors are important vehicles for delivering therapeutic genes into mammalian cells. However, the yield of the adenoviral transduction of murine mesenchymal stromal cells (MSC) is low. Here, we aimed to improve the adenoviral transduction efficiency of bone marrow-derived MSC. Our data showed that among all the potential transduction boosters that we tested, the K2 Transfection System (K2TS) greatly increased the transduction efficiency. After optimization of both K2TS components, the yield of the adenoviral transduction increased from 18% to 96% for non-obese diabetic (NOD)-derived MSC, from 30% to 86% for C57BL/6-derived MSC, and from 0.6% to 63% for BALB/c-derived MSC, when 250 transduction units/cell were used. We found that MSC derived from these mouse strains expressed different levels of the coxsackievirus and adenovirus receptors (MSC from C57BL/6≥NOD>>>BALB/c). K2TS did not increase the level of the receptor expression, but desensitized the cells to foreign DNA and facilitated the virus entry into the cell. The expression of Stem cells antigen-1 (Sca-1) and 5′-nucleotidase (CD73) MSC markers, the adipogenic and osteogenic differentiation potential, and the immunosuppressive capacity were preserved after the adenoviral transduction of MSC in the presence of the K2TS. In conclusion, K2TS significantly enhanced the adenoviral transduction of MSC, without interfering with their main characteristics and properties. 相似文献
103.
Violeta Mircevska Vladimir Bickovski Ivana Aleksov Viktor Hristovski 《Engineering Analysis with Boundary Elements》2013,37(3):624-636
Fluid–structure interaction phenomenon, by its nature, is three-dimensional and consequently dependant on the shape of a dam and canyon that in-fact defines the spatial domain where the generated acoustic waves are spread. The complex topography of the terrain in general requires sufficiently large extent of reservoir to be included in the model, which is undoubtedly feasible if BEM technique is used. This paper shows that the irregular canyon shape dictates “the most adequate” location of the truncation surface that gives the smallest negative impact on calculation accuracy. The derived conclusions are based on various 3D analyses of a rigid dam–reservoir system with different shapes and lengths of the fluid domain, where the fluid is treated as incompressible and inviscid. The presented work contributes towards disclosure of the topographic site effects and towards promotion of simple and effective procedure for generation of BE mesh, which is quite accurate in following the topology of the terrain. 相似文献
104.
Ethanolic extracts prepared from the fruits of three cultivars of black currant (‘Record’, ‘Blackdown’ and ‘Ronix’) macerated in three concentrations (40%, 60% and 96%) of aqueous ethanol were investigated for their anthocyanins profile, total phenolics and antioxidant activity. 相似文献
105.
María Rojas Isabel González Violeta Fajardo Irene Martín Pablo E. Hernández Teresa García Rosario Martín 《Food Control》2009,20(10):896-902
Polymerase chain reaction (PCR) based on oligonucleotide primers targeting the mitochondrial 12S rRNA gene has been applied to the specific identification of meats from quail (Coturnix coturnix), pheasant (Phasianus colchicus), partridge (Alectoris spp.), and guinea fowl (Numida meleagris). The use of specific primers pairs for quail, pheasant, partridge and guinea fowl allowed the selective amplification of the desired avian sequences. The specificity of each primer pair was verified by PCR analysis of DNA from meats of various game and domestic bird and mammalian species. The assay can be useful for the accurate identification of meats from game bird species, avoiding mislabelling or fraudulent species substitution in meat products. 相似文献
106.
Violeta Petkova 《Cement and Concrete Research》2005,35(5):926-930
The paper treats the use of modelling of the mixture proportioning of a new composite material (CM) on the basis of combined utilization of secondary industrial by-products [V. Petkova, Composition of Heavy Strength Concrete, Patent Ser. B No. 60100, 03.10.19094, Bulgaria]. A three-parameter polynomial model is used for the determination of the amount of the composite components cement, active additive and granulated blast-furnace slag. It is shown that using this approach, the component's influence on the changes of compressive strength in the course of up to one-year hardening of the composite can be evaluated. 相似文献
107.
A new diol with bistriazene groups, 1,1′[4,4′‐diphenylether]‐3,3′‐di(β‐hydroxyethyl methyl)‐bistriazene (BTD), was synthesized and characterized. BTD, along with N‐methyldiethanolamine as a chain extender, was used to prepare a segmented polyurethane based on poly(tetramethylene oxide) diol (weight‐average molecular weight = 2000) and 2,4‐tolylene diisocyanate (80:20 v/v 2,4‐/2,6‐isomer mixture). Subsequent quaternization of the amine with benzyl chloride formed the cationomer. The structure–property relationships, including the photochemical behavior of the triazene linkage in these polymers, were investigated with respect to another polyurethane prepared from 4,4′‐diphenylmethane diisocyanate and a bistriazene compound. Photolysis experiments were carried out in polymer solutions and in the film state, and the reduction of the π–π* absorption band, characteristic of the triazene chromophore in ultraviolet spectra, was followed. A kinetic evaluation revealed a first‐order photoprocess. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 385–391, 2005 相似文献
108.
Elvira Gonzlez de Mejía Violeta Martínez‐Resendiz Eduardo Castao‐Tostado Guadalupe Loarca‐Pia 《Journal of the science of food and agriculture》2003,83(10):1022-1030
The objective of the present study was to investigate the effect of drought on the metabolism of proline, ornithine and polyamines, and the enzymes involved in their synthesis and degradation, in tepary and common bean seeds. Furthermore, the effect on seed yield, protein content and in vitro protein digestibility was also studied. Genotypes of tepary bean (Phaseolus acutifolius) used were: PI‐301‐801 from Nicaragua; G‐400‐35 from Oaxaca, Mexico; L‐242‐24 and L‐242‐36 from Sonora, Mexico; L‐172 from Arizona, USA; and the common bean (Phaseolus vulgaris) variety Flor de Mayo Bajío (FMB) from Mexico. The cultivars were grown in a greenhouse under controlled temperature, light and humidity. Water content in plants (WCP) decreased when irrigation was stopped (1 and 2 weeks after blooming). Common bean had the lowest WCP value (73.75%), while the best genotypes were PI‐301‐801 (91.62%), G‐400‐35 (88.70%) and L‐242‐24 (85.73%). Tepary bean plants had superior water absorption capacity, which helped to increase yield. De novo synthesis of drought proteins may explain the increased protein content present under drought conditions. The results suggest that water stress induced ornithine amino transferase activity and ornithine concentration. Proline also increased under drought conditions (p < 0.05). Genotypes L‐242‐24 and G‐400‐35, which had the highest yield, also had a major concentration of polyamines under water stress. The results also suggest that arginase activity participated in amino acid synthesis such as ornithine and, consequently, in the protein concentration under water stress. Genotypes G‐400‐35 and L‐242‐24 are good alternatives for cultivation in arid zones. Copyright © 2003 Society of Chemical Industry 相似文献
109.
Shallow and ultrashallow p-n junctions were formed in Si by stimulated diffusion of P from phosphosilicate glass and B from borosilicate glass under pulsed photon annealing. Electrical, photoelectric, and optical properties of these junctions were investigated. Special features of stimulated diffusion of P and B in surface layers of Si under pulsed photon annealing were revealed. The obtained results are discussed in terms of kick-out, pair vacancy-interstitial, and dissociative diffusion mechanisms. The features of the dopant concentration profiles are explained in terms of the vacancy-interstitial mechanism and the stimulated diffusion model with allowance made for the time dependence of the dopant surface concentration and the concentration dependence of the diffusivity. 相似文献
110.
Application of a polymerase chain reaction to detect adulteration of ovine cheeses with caprine milk
Inés López-Calleja Díaz Isabel González Alonso Violeta Fajardo Irene Martín Pablo Hernández Teresa García Lacarra Rosario Martín de Santos 《European Food Research and Technology》2007,225(3-4):345-349
A polymerase chain reaction (PCR) procedure has been applied for the detection of caprine milk in ovine cheeses by using primers
targeting the mitochondrial 12S ribosomal RNA gene. The use of a primer pair specific for goat in PCR analysis of cheese samples,
enabled the amplification of a goat 122 bp fragment with a sensitivity threshold of approximately 1%, whereas no amplification
signal was achieved with sheep's, cow's and water buffalo's milk DNA. This study demonstrates the usefulness of the proposed
PCR assay for the qualitative detection of goats’ milk in ewes’ cheeses, and may therefore provide a simple and accurate approach
applicable to the authentication of cheese or other dairy products in routine monitoring programs. 相似文献