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11.
Abellán A Cayuela JM Pino A Martínez-Cachá A Salazar E Tejada L 《Journal of the science of food and agriculture》2012,92(8):1657-1664
BACKGROUND: Enzymes present in the flowers of Cynara cardunculus (cyprosins) are used in the production of some traditional Spanish and Portuguese cheeses, replacing animal rennet. The aim of this work was to study the changes that take place in free amino acids during the ripening of a goat's milk cheese (Murcia al Vino) manufactured with plant coagulant (PC) or animal rennet (AR). RESULTS: The total free amino acid (TFAA) concentration increased during ripening, with Ile, Val, Ala, Phe, Gaba, Arg and Lys representing more than 50% of the TFAA content at 60 days in both types of cheese. The TFAA concentration was significantly higher in cheeses made with PC (854 mg 100 g?1 total solids (TS)) than those made with AR (735 mg 100 g?1 TS). The concentration of most free amino acids, especially His, Ser, Gln, Thr, Ala, Met and Ile, was higher in the PC cheese. CONCLUSION: Cheese made using PC as coagulant presented higher contents of free amino acid throughout the ripening period than cheese made using AR. Therefore we can conclude that the use of PC to produce Murcia al Vino goat's cheese would accelerate the ripening process as a result of increased cyprosin proteolytic activity. Copyright © 2011 Society of Chemical Industry 相似文献
12.
Males of the parasitoid wasp Pimpla disparis Viereck (Hymenoptera: Ichneumonidae) aggregate on parasitized gypsy moth, Lymantria dispar, host pupae when the emergence of a prospective mate is imminent or under way. We tested the hypotheses that the developing
parasitoid (“DePa”) inside the host pupal case produces a pheromone that attracts and arrests mate-seeking males, and that
the pheromone is most effective during the emergence of the parasitoid from the host. Results obtained in two-choice laboratory
experiments, with 4–7-d-old virgin males, indicate that (1) DePa-derived semiochemicals arrest males, (2) the opening of a
host pupal case strongly arrests males, and (3) the arrestment cue emanates from oral fluid secreted by both female and male
parasitoids while they chew their way out of a host pupal case. This phenomenon implies that emerging females, which are haplodiploid
and can reproduce without mating, do not engage in active pheromone signaling to attract males, and that mate-seeking males
co-opt chemicals involved in eclosion as a mate-finding cue, taking a 50% chance that the prospective mate is a female. 相似文献
13.
María Florencia Torres Rita H. de Rossi Mariana Adela Fernández 《Journal of surfactants and detergents》2013,16(6):903-912
The mixed system of an anionic hydrocarbon surfactant, sodium dodecyl sulfate, and a perfluorinated surfactant, perfluorononanoic acid (PFNA), was investigated by a combination of methods. The critical micellar concentrations (CMC) were determined over a wide range of sample compositions by surface tension, conductivity and UV–visible spectrophotometry using N-(4-nitrophenyl)perfluorononanamide as a molecular probe. The values of CMC obtained by different techniques were in good agreement. In addition, the aggregation numbers were determined in the mixtures with a low content of hydrocarbon surfactant, by measuring the fluorescence quenching of pyrene. The hydrodynamic radii of the aggregates were estimated through the diffusion ordered 19F- and 1H-NMR spectroscopy. The values obtained are in agreement with those expected according to the measured aggregation numbers. The analysis of the data with different aggregation models suggests the formation of a non-ideal mixed micelle that is enriched in the perfluorinated surfactant when its mole fraction increases, and that is practically formed by PFNA only at mole fractions higher than 0.8. 相似文献
14.
Mothers, fathers, and their 6-year-old children (N?=?164) participated in a study testing key tenets of the specific emotions model of marital conflict. Parents reported their marital conflict strategies, were observed interacting with their children, and rated children's behavioral adjustment. Children reported their emotional reactions to specific interparental conflicts. Results support the specific emotions model. Children's behaviors mirrored the marital or parental behaviors of same-gender parents. Indirect effects of marital aggression through parental behavior were detected, and marital and parental behaviors interacted to predict girls' externalizing. Girls' anger, sadness, and fear increased with fathers' marital aggression. Fear and the anger by fear interaction predicted girls' internalizing. Fathers' marital aggression interacted with anger to predict externalizing and interacted with fear to predict internalizing behavior in boys. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Francisco Márquez-Montesino Neil Torres-Figueredo Adela Lemus-Santana Fernando Trejo 《化学工程与技术》2020,43(9):1716-1725
Activated carbon (AC) was gained from Pinus montezumae (PM) wood sawdust and chemical activation with K2CO3 was used for obtaining activated carbons. Variations in reaction conditions such as temperature, impregnation ratio (IR), and activation time were carried out to study their influence on the specific surface area (SSA) and average pore volume (APV) in AC. Materials were analyzed by means of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) to determine the functional groups, pore structure, and morphology of pine sawdust and activated carbons. Activated carbons were amorphous in nature with some crystalline regions. 相似文献
16.
Amaia Garcia-Pena Jaime Ibarrola Adela Navarro Alba Sadaba Carolina Tiraplegui Mattie Garaikoetxea Vanessa Arrieta Lara Matilla Amaya Fernndez-Celis Rafael Sadaba Virginia Alvarez Alicia Gainza Eva Jover Natalia Lpez-Andrs 《International journal of molecular sciences》2021,22(5)
Mitral valve disease (MVD) is a frequent cause of heart failure and death worldwide, but its etiopathogenesis is not fully understood. Interleukin (IL)-33 regulates inflammation and thrombosis in the vascular endothelium and may play a role in the atherosclerotic process, but its role in mitral valve has not been investigated. We aim to explore IL-33 as a possible inductor of myxomatous degeneration in human mitral valves. We enrolled 103 patients suffering from severe mitral regurgitation due to myxomatous degeneration undergoing mitral valve replacement. Immunohistochemistry of the resected leaflets showed IL-33 and ST2 expression in both valve interstitial cells (VICs) and valve endothelial cells (VECs). Positive correlations were found between the levels of IL-33 and molecules implicated in the development of myxomatous MVD, such as proteoglycans, extracellular matrix remodeling enzymes (matrix metalloproteinases and their tissue inhibitors), inflammatory and fibrotic markers. Stimulation of single cell cultures of VICs and VECs with recombinant human IL-33 induced the expression of activated VIC markers, endothelial–mesenchymal transition of VECs, proteoglycan synthesis, inflammatory molecules and extracellular matrix turnover. Our findings suggest that the IL-33/ST2 system may be involved in the development of myxomatous MVD by enhancing extracellular matrix remodeling. 相似文献
17.
Ratikanta Mishra Ales Kroupa Adela Zemanova Herbert Ipser 《Journal of Electronic Materials》2013,42(4):646-653
Phase equilibria in the ternary Ni-Sb-Sn system are of interest for high-temperature soldering, both considering ternary alloys as solder materials themselves or as the basis for understanding the reactions between Sb-Sn-based solders and Ni-based substrates. Therefore, the Sn-rich corner of the ternary Ni-Sb-Sn phase diagram with Sn content of more than 75 at.% was investigated by a combination of powder x-ray diffraction (XRD), differential thermal analysis (DTA), and electron probe microanalysis (EPMA). Ternary phase equilibria and phase compositions of the respective equilibrium phases were determined within the isothermal section at 200°C, and two isopleths were constructed for constant Sn contents of 80 at.% and 85 at.%. The experiments were supported by CALPHAD-type calculations of this ternary system to yield a consistent reaction scheme which shows four invariant ternary transition reactions in this composition range. A liquidus projection is presented, accompanied by the corresponding Scheil diagram. 相似文献
18.
19.
Preparation and characterization of membranes obtained from blends of acrylonitrile copolymers with poly(vinyl alcohol) 下载免费PDF全文
Teodor Sandu Andrei Sârbu Celina Maria Damian Adela Marin Silviu Vulpe Temenuzhka Budinova Boyko Tsyntsarski M. Ferhat Yardim Ahmet Sirkecioglu 《应用聚合物科学杂志》2014,131(21)
New microfiltration and ultrafiltration membranes were obtained using acrylonitrile‐vinyl acetate copolymers in mixture with poly(vinyl alcohol) (PVA). Thus, a blend polymer solution was prepared in dimethylsulfoxide (DMSO) and used to obtain bicomponent polymer membranes by phase inversion. The rheological behavior of the DMSO polymer solutions was, mostly, dilatant at low shear gradients and pseudo plastic with quasi Newtonian tendency at higher gradients. Membranes were characterized by Fourier transform infrared spectrometry (FTIR), optical microscopy, atomic force microscopy, thermal gravimetric analysis‐differential thermal gravimetry, and pure water flux (PWF). FTIR spectra displayed the characteristic bands for acrylonitrile, vinyl acetate, and PVA. The morphology and the porosity can be tailored by the preparation conditions. PVA allows controlling the size of the pores and enables, in principle, to use the resulted membranes as supports for enzyme immobilization. PVA content influences the thermal stability. PWF values depend on the copolymer, on the content in PVA, but also on the coagulation bath composition. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41013. 相似文献
20.
Mărghitaş Liviu Al Dezmirean Daniel Adela Moise Otilia Bobis Laura Laslo Stefan Bogdanov 《Food chemistry》2009
In this study, we investigated and compared the physico-chemical properties (moisture, colour, ash, and sugars content) as well as total phenols, total flavonoids and antioxidant activity of several honey samples (24) collected from different regions of Romania. The physico-chemical values were in the range of approved limits (conforming to EU legislation); excepting the monosaccharide values for one sample (T2). For this sample, the other values were within legislation limits. The results obtained showed that the most valuable honey is the honeydew one. Correlation between RSA and total phenols and total flavonoids, respectively, was determined, and a positive correlation was found. This study demonstrates remarkable variation in antioxidant properties and content of total phenols in honey, depending on its botanic or geographic source. 相似文献