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Breadmaking is a complex process that involves a series of parameters that must be controlled. Rheological measurements are often used to predict the behavior of wheat dough during processing and the quality of the final product. There are many different dietary fiber sources that can be used to enhance the nutritional quality of bread. However, they will affect processing and final product quality. Response surface methodology (RSM) was employed to study the effects of adding different dietary fiber sources (wheat bran, resistant starch, and locust bean gum) on farinographic parameters of wheat flour. The experiments were conducted according to a 23 central composite rotational design (CCRD). With the experimental results or responses (farinographic parameters), the effect of each variable was calculated and the interactions between them were determined. Models that explain the effects of the different fiber sources on water absorption, arrival time, dough development time, and mixing tolerance index of wheat flour were established. The fiber sources interacted for some of the parameters analyzed, demonstrating that if two or more sources of dietary fiber are present in the mix, they might act different to what would be expected of the sum of them. It was also noticed that for most parameters, wheat bran and locust bean gum had a greater influence on farinographic parameters than resistant starch. The simultaneous presence of the three fibers, within the ranges studied, contributed to an increase in water absorption, arrival time, and mixing tolerance index, and to a reduction in departure time and dough stability.  相似文献   
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Pulsed laser deposition (PLD) is a conceptually and experimentally simple yet highly versatile tool for thin-film and multilayer research. Its advantages for the film growth of oxides and other chemically complex materials include stoichiometric transfer, growth from an energetic beam, reactive deposition, and inherent simplicity for the growth of multilayered structures. With the use of PLD, artificially layered materials and metastable phases have been created and their properties varied by control of the layer thicknesses. In situ monitoring techniques have provided information about the role of energetic species in the formation of ultrahard phases and in the doping of semiconductors. Cluster-assembled nanocrystalline and composite films offer opportunities to control and produce new combinations of properties with PLD.  相似文献   
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The use of high-resolution NMR and high-resolution diffusion-ordered spectroscopy (DOSY) for the characterization of selected Port wine samples of different ages with the aim of identifying changes in composition is described. Conventional 1D and 2D NMR methods enabled the identification of about 35 compounds, including minor components such as some medium-chain alcohols, amino acids, and organic acids. High-resolution (HR) DOSY extended sample characterization, increasing the number of compounds identified and NMR assignments made, by providing information on the relative molecular sizes of the metabolites present. Port wines of different ages were found to differ mainly in their content of (a) organic acids and some amino acids, (b) an unidentified possible disaccharide, and (c) large aromatic species. The relative amount of these last high Mw aromatics is seen to decrease significantly in the oldest wine, as expected from the known formation and precipitation of anthocyanin-based polymers during red wine aging.  相似文献   
5.
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated. Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate (EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to 150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important source of some minerals.  相似文献   
6.
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2.  相似文献   
7.
An iron-sulfur compound (Fe3S2) was synthesized at pressures greater than 14 gigapascals in the system Fe-FeS. The formation of Fe3S2 changed the melting relations from a simple binary eutectic system to a binary system with an intermediate compound that melted incongruently. The eutectic temperature in the system at 14 gigapascals was about 400°C lower than that extrapolated from Usselman's data, implying that previous thermal models of Fe-rich planetary cores could overestimate core temperature. If it is found in a meteorite, the Fe3S2 phase could also be used to infer the minimum size of a parent body.  相似文献   
8.
The objective was to evaluate the animal thermal comfort indices from two integrated crop-livestock-forestry (ICLF) systems. For this, temperature–humidity index (THI), black globe temperature and humidity index (BGHI), and the radiant thermal load (RTL) were assessed. Two ICLF (ICLF-1 and ICLF-2) systems and one control system were established. On the ICLF systems, the arboreal component was the eucalyptus tree (Eucalyptus grandis × Eucalyptus urophylla; H13 clone), planted in simple wide-spaced rows. The ICLF-1 system had a tree spacing of 14 × 2 m with 357 trees per hectare, and the ICLF-2 had a tree spacing of 22 × 2 m with 227 trees per hectare. The control system had five scattered native trees per hectare, pertaining to Gochnatia and Dipteryx species. The forage component in all three systems was piatã-grass (Brachiaria brizantha cv. BRS Piatã). The experimental design was a randomized block in a sub-subplot design scheme with four replications. The presence of shade provided by the trees offered better conditions of animal comfort when compared with the condition of full sun. The ICLF-1 system, with higher tree density, provided better indicators for thermal comfort, THI, BGHI, and RTL when compared with the condition of full sun, while ICLF-2 was no different than ICLF-1 for BGHI.  相似文献   
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Different stunning methods (carbon dioxide [CO2] and hypothermia) used in industrial fish processing were compared with asphyxia in air, which is used in traditional fishing, to evaluate the effects of these methods on the stress responses and the meat quality of the Amazon hybrid surubim, Pseudoplatystoma fasciatum female × Leiarius marmoratus male. After the application, blood and behavioral indicators were evaluated. Following death by gill cutting, the fish were gutted, and analyses of muscle pH, rigor mortis, the exudation of the meat, and coloration were performed. Significantly higher levels of cortisol and glucose were exhibited by the fish subjected to asphyxia than by the fish stunned by either CO2 or hypothermia. The fish subjected to asphyxia displayed decreasing muscle pH during the first 2 h after death and showed higher rates of rigor mortis after 3 h than the fish that were stunned by the other two methods. The asphyxia is a practice that exposes fish to suffering by causing an increase in stress responses, which affects meat quality. The immersion of fish in water and ice (hypothermia) for 5 min was more effective stunning method than the use of CO2, resulting in higher loss of sensibility and greater welfare.  相似文献   
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