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91.
92.
The effects of exogenous growth factors (indolacetic acid, gibberellic acid and kinetin and steroidal hormones (estrone, estradiol and testosterone on the germination pattern of Pinus pinea seeds were studied. Nucleic acids metabolism during the stages before germination, has also been investigated. Seeds sown in the presence of all these substances, showed a higher growth rate and a higher germination degree than their respective controls; kinetin and estradiol were the most active factors. The level of total nucleic acids was studied in seeds after one day soaking and on the 1rst, 3rd, 5th, and 7th day after sowing. Megagametophytes contained a higher amount of acids when growth factors and steroidal hormones were present, specially after one day soaking. In embryos; after the 3rd day, a similar result was obtained. The RNA fraction increased the most.  相似文献   
93.
An efficient method for the determination of nanogram levels of zinc in waters (potable, irrigation, waste and sea waters) is described. Acidified water samples were analyzed by an accurately optimized time/temperature program for electrothermal atomic absorption spectrometry. The samples were previously treated with a matrix modifier consisting of 0.1% Mg(NO3)2 in 0.5 M HNO3 and injected through a graphite tube with L'Vov platform. Sample recoveries, repeteability, and analyses of NIST reference material demonstrated the reliability and accuracy of this technique. Zinc concentrations ranged from 2.0 to 73.0 microg l(-1). No significant differences among the mean zinc levels determined in the four types of water considered from southeastern Spain were found. Zinc concentrations in waters from the zone were not affected by human and industrial activity.  相似文献   
94.
We have carried out a new study of the color combinations selected by Le Corbusier in ‘les claviers de couleurs’ for the Salubra wallpaper company in 1931, by analyzing them in the Natural Color System, which allows us to understand the perceptive variables of colors (hue, blackness, and chromaticness) as well as their combination criteria. Regarding the perceptive variables, we have discussed the selected hue ranges in relation to other color proposals of Le Corbusier himself, and we have shown the extensive presence of earthy hues, or the noteworthy absence of other colors such as yellows, violets, black, and white. We have also analyzed the chromaticness of colors, which is generally low, and the blackness, also very limited. In relation to the combination criteria, we aim to find out the underlying order in the color combinations by studying the similarities and contrasts of their perceptive variables. We demonstrate graphically, by a navigable three‐dimensional model, and with statistical support, some principles in Le Corbusier's color preferences, such as the combination of colors with equal chromaticness, the search of some contrast in blackness, or the usual resource of contrasting cool with warm colors, something slightly different to the contrast of complementary colors. We have also discussed other compositional criteria held by Le Corbusier to use color in his Purist architecture, which are related to the position and proportion of the surfaces to be colored, the connotations associated to different hues, or the use of plain colors, among others. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 85–100, 2016  相似文献   
95.
The effect of high pressure treatment on the hydrolysis of fish skin gelatin and the antioxidant properties of the hydrolysates was evaluated. Hydrolysis was performed by Alcalase, collagenase, trypsin and pepsin both at atmospheric pressure and under high pressure (100 MPa/15 and 30 min, 200 MPa/15 and 30 min, 300 MPa/15 min). The degree of hydrolysis (DH) was determined according to the base consumption via pH‐stat as well as the percentage of soluble nitrogen in trichloroacetic acid (TCA). About 16% of nitrogen in the gelatin was still soluble in 10% TCA, indicative of a significant amount of low molecular weight components. The high pressure treatment increased the DH with all the enzymes used between 5% and 10%. However, in comparison with the hydrolysates obtained at atmospheric pressure after 3 h of digestion under controlled conditions (using a pH‐stat), the radical scavenging capacity of the pressured hydrolysates was only significantly enhanced when Alcalase or collagenase were used. High pressure may be a useful tool for the quick obtaining of gelatin hydrolysates with antioxidant capacity.  相似文献   
96.
97.
Taking into account consumers’ perception in new product development has been regarded as a key strategy to developing more successful food products. In this context, consumer profiling techniques have increased their popularity in the last decade. The aim of the present work was to compare four consumer profiling techniques (sorting, projective mapping, intensity scales and check‐all‐that‐apply questions) in orange‐flavoured powdered juice drinks. A consumer study was carried out with 200 regular consumers of the category, which were divided into four groups. Each group used a different methodology to evaluate seven commercial powdered drinks. After completing the task consumers were asked to rate its difficulty on a nine‐point hedonic scale. Results showed that the four evaluated methodologies were able to identify differences in consumers’ perception of the sensory characteristics of the drinks, providing similar information. However, the application of CATA questions and intensity scales was regarded as easier for consumers. Advantages and disadvantages of the evaluated methodologies are discussed.  相似文献   
98.
99.
This study establishes data on polyphenols, tocopherols, and antioxidant capacity (AC) of virgin argan oil. A total of 22 samples from Morocco were analyzed. Total polyphenol content ranged between 6.07 and 152.04 mg GAE/kg. Total tocopherols varied between 427.0 and 654.0 mg/kg, being γ‐tocopherol the major fraction (84.68%); α‐, β‐, and δ‐tocopherols represent 7.75, 0.33, and 7.29%, respectively. No influence of oil extraction method on total tocopherols was observed. The AC of argan virgin oils determined by the ABTS method in n‐hexane oils dilution ranged between 14.16 and 28.02 mmol Trolox/kg, and by the ABTS, DPPH, and FRAP methods in methanolic oil extracts between 2.31–14.15, 0.19–0.87, and 0.62–2.32 mmol Trolox/kg, respectively. A high correlation was found between ABTS and DPPH methods applied to a methanolic oil extract. Virgin argan oil presents a higher polyphenol and tocopherol content, and total AC than other edible vegetable oils.  相似文献   
100.
One hundred six female Holstein calves [body weight (BW) = 41.5 ± 0.37 kg and 11.2 ± 0.3 d old] were used to evaluate the effects of physical form of a starter on animal performance and starter intake. Calves were randomly allocated to 2 treatments consisting of either a multiparticle or a pelleted starter. Both starters had exactly the same ingredient and nutrient composition but differed in their physical form. Calves received 4 L/d of the same milk replacer at a 150 g/kg dilution rate in 2 offers of 2 L each until they consumed an average of 300 g/d of starter (as fed) for 2 consecutive days; then the dilution rate was decreased to 120 g/kg until the age of 49 d when milk replacer was limited to 1 daily dose of 2 L until 57 d of age. Calves were kept in individual hutches for at least 1 wk after weaning. Body weight was measured at the beginning of the study and at 49 and 64 d of age. The median perimeters for the multiparticle and pelleted starters were 0.61 ± 0.016 and 2.71 ± 0.082 cm, respectively. Overall starter consumption was greater in calves receiving the multiparticle starter (944.8 ± 30.01 g/d) than in those receiving the pelleted starter (863.9 ± 32.04 g/d). There were no differences in the total milk replacer intake between the 2 treatments. Calf BW when leaving the individual hutches at the end of the study was similar between both treatments. Consequently, feed conversion efficiency was greater in calves consuming the pelleted than the multiparticle starter up to 64 d of age, mainly due to the greater conversion efficiency obtained with the pelleted than with the multiparticle starter after the preweaning period. It is concluded that pelleted starters may result in lower dry feed consumption compared with multiparticle starters, but because final BW was similar in both treatments, feed efficiency of calves consuming pelleted starters may be greater than that of calves consuming multiparticle starters. Therefore, when feeding a starter with similar nutrient composition to the one used in this study, there seems to be an economic advantage associated with feeding the starter in a pelleted form compared with a multiparticle form.  相似文献   
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