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21.

The studied hypothesis is that the herbicide glyphosate (GLY) can affect the oxidative balance in the hydrophobic intracellular medium in non-target Chlorella vulgaris cells. Analytical GLY and RoundUp (RUP) supplementation, affected the growth profile. A significant 42% decrease in the cellular biomass in stationary (St) phase was observed in cultures supplemented with either 5 µM of GLY or RUP, as compared to control cultures. The treatment with 0.3 µM of GLY generated non-significant effects on the oxidation rate of 2’, 7’ dichlorofluorescein diacetate (DCFH-DA), neither in exponential (Exp) nor in St phase of development, as compared to control cultures. However, the treatment with either 5 µM GLY or 0.3 and 5 µM RUP lead to a significant decrease in the DCFH-DA oxidation rate, as compared to control cultures. The lipid radical (LR) generation rate, detected by Paramagnetic Resonance Spectroscopy (EPR), was significantly increased in the presence of RUP, in Lag and Exp phase of growth. The non-enzymatic antioxidants, α-Tocopherol (α-T) and β-Carotene (β-C), are aimed to protect membranes against the damage produced by the radical reactions. The content of β-C was not significantly affected, as compared to control cultures, by any of the treatments, in both growth phases of cellular development. The content of α-T was significantly decreased by the supplementation with either 0.3 or 5 µM of RUP or 5 µM GLY. The LR/α-T ratio, used as indicator of the oxidative balance in the hydrophobic cellular media, was significantly different between samples obtained from control and RUP-exposed microalgae in both, Exp and St phase of development, with either 0.3 or 5 μM RUP. The data presented here showed evidence that suggested that oxidative balance in the hydrophobic environment was affected by either GLY or RUP.

  相似文献   
22.
In grapevines, stomatal aperture decreases after a mid-morning peak during summer days. Afternoon stomatal closure increases in non-irrigated plants as water limitation progresses, which suggests the involvement of abscisic acid (ABA) in the control of stomatal aperture. The objective of this work was to study the seasonal and diurnal time-courses of CO2 assimilation rate, leaf conductance, leaf water potential +, and ABA concentration in xylem sap, leaves, flowers and berries in non-irrigated field-grown Tempranillo grapevines throughout reproductive development. Leaf decreased throughout fruit development because water availability decreased towards the end of the reproductive cycle. CO2 assimilation rate, leaf conductance and xylem ABA concentration also decreased during the course of the growing season. Combining all measurements xylem ABA was either not correlated, or only slightly correlated, with leaf water status + and daily leaf conductance, respectively. This lack of relationship indicates that xylem ABA during fruit ripening had functions other than provision of a non-hydraulic signal. On a seasonal basis, xylem ABA concentration measured in non-irrigated grapevines was well related to berry ABA concentration, especially at the end of fruit development (veraison and harvest).  相似文献   
23.
Ascorbic acid levels in 13 types of commercially packaged orange juices and a juice drink were monitored over 5–7 days at 4.5°C as stored in the original container. Comparable samples stored in an open plastic container were monitored for comparison. In both cases the average ascorbic acid loss was about 1.5–2% per day. These simulated consumer home conditions showed that juice retained an average of 88% of the original ascorbic acid after 1 wk, and 67% after 2 wk in opened containers stored at typical home refrigerator temperatures.  相似文献   
24.
A selected group of 195 oils from the Spanish “Toxic Oil” Syndrome (TOS) epidemic including 29 high-probability “case” and 64 “control” oils were examined to investigate the relationship between oil composition and the risk of TOS. As indicated by fatty acid and sterol patterns, the presence of rapeseed oil was significantly more prevalent in the case than in the control oils, but fatty acid anilides were the most useful markers of case-related samples. Anilides were detected in 62% of case oils and at lower concentrations in 23% of the control samples. The ratios of individual anilides were quite constant in these oils and most consistent with their formation in the original (undiluted) rapeseed oil.  相似文献   
25.
The objective of this study was to determine the effect of the partial homogenization of milk and the use of an adjunct lactic culture on the processing, quality and yield of low-fat Chanco cheese.
  Treatments were: T1 normal-fat control and T2 low-fat control. The low-fat treatments were: T3 using homogenized milk, T4 with adjunct lactic culture and T5 both variables.
   It was concluded that the homogenization slightly increased the time of rest after cutting of the curd, and the addition of adjunct lactic culture increased the acidity of whey during a second agitation. Nevertheless, the total time and pH at the end of the process were normal and without significant statistical difference ( P  > 0.05) between treatments. When using homogenized milk the losses of fat in whey decreased by 50% with respect to the low-fat control and nearly 80% in relation to the full fat control. Consequently, the yield was increased. The physical and chemical characteristics of the Chanco cheese were not affected by the studied variables. With respect to the sensory evaluation, significant differences in colour and aroma did not appear, but there were statistically significant differences (P <  0.05) in taste, hardness, adhesiveness, cohesiveness and elasticity between the full-fat control and all the low-fat treatments. In the case of general acceptance, the treatment with adjunct lactic culture was similar to the full-fat control. In addition, it showed the least difference (mild) in elasticity and taste in relation to this control .  相似文献   
26.
This study concerns the ozonation of Resorcinol, Phloroglucinol and 1,3 Cyclohexanedione in the presence of bromide ion in a bubble column, prior to chlorination. Preozonation in aqueous solutions reduces the potential for forming chlorinated trihalomethane compounds. At organic concentrations greater than 10?4?M a short ozonation time increases the potential for forming trihalo compounds. At longer ozonation times the reverse is true. Finally the influence of mass transfer and chemical reaction on the ozone absorption rate have been evaluated following the film theory.  相似文献   
27.
基于近红外高光谱图像的冬枣损伤早期检测   总被引:1,自引:0,他引:1  
为了对冬枣损伤进行早期检测,采用近红外高光谱图像技术对损伤区域成像。针对高光谱图像波长多的特点,分别采用连续投影算法、相关特征选择算法、一致性(Consistency)算法选择冬枣损伤的特征波长,对提取的特征波长分别应用k-邻近、朴素贝叶斯(naive bayes,NB)、支持向量机(support vector machine,SVM)3种分类方法进行损伤区域识别。结果表明:所有方法选择的一致特征波长在1 353 nm和1 691 nm附近。Consistency算法选择的特征波长在SVM分类器下分类识别正确率达到95.16%,一致特征波长在NB分类器下分类识别正确率达到84.26%,验证了一致波长的有效性,为多光谱成像技术实现在线检测冬枣损伤提供参考依据。  相似文献   
28.
The optical and structural properties of r.f. sputtered CeO2 thin films deposited on Pyrex substrates have been studied as a function of substrate temperature during deposition. The refractive index, n, extinction coefficient, k, and bandgap of the films were calculated from reflectance, R, and transmittance, T, spectra in the wavelength range 340–900 nm. The refractive index of CeO2 films at 550 nm comprises values from about 2.25–2.4 depending on the substrate temperature during deposition. The extinction coefficient was negligible for wavelength values higher than 400 nm. The value obtained for the bandgap was 3.1 eV. The X-ray diffraction patterns showed the same (f c c) cubic structure with preferential orientation depending on substrate temperature during deposition. The scanning force microscope measurements showed that the roughness and grain size of the CeO2 films increase with increasing substrate temperature. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
29.
Browning prevention of avocado halves using polyphenol oxidase (PPO) inhibitors along with sulfites was investigated. Browning inhibitiors were selected on the basis of the inhibition of a crude extract of avocado PPO. The most effective inhibitors were ascorbic acid and sodium sulfite, these compounds plus citric acid were mixed to get an inhibitory solution. In vivo experiments were performed on avocado halves by measuring Hunter color values after 15 days' storage to test the potential of solutions to prevent browning. Results showed that immersion in solutions along with refrigerated storage was needed to get an inhibitory effect. Color preservation was not due to oxygen exclusion nor to low pH and sulfite was unnecessary. The best treatment was the storage of avocado halves in a 1% ascorbic acid/1 % citric acid solution at pH 5 and 7C.  相似文献   
30.
PSYCHOLOGICAL EFFECTS OF UNILATERAL AND BILATERAL SUBCORTICAL SURGERY WERE EXAMINED. SPECIFICALLY, COGNITIVE AND PERCEPTUAL FUNCTIONS AND PERFORMANCE ON VISUAL AND AUDITORY TASKS OF RECENT RECALL WERE COMPARED IN THE STABILIZED POSTOPERATIVE SITUATION FOR SS UNDERGOING NO SURGERY, UNILATERAL RIGHT OR LEFT, AND BILATERAL CRYOTHALAMECTOMY. NO SIGNIFICANT CHANGES (P > .05) OBTAINED ON ANY OF THESE BEHAVIORAL DIMENSIONS. THE DISCUSSION FOCUSED ON THE RESILIENCE OF SO-CALLED "HIGHER INTEGRATIVE" ACTIVITIES AND THE FUNCTIONAL DUPLICATION OR EQUIVALENCE APPARENT AT THE SUBCORTICAL CORE. THE POSSIBILITY OF THE CONTRIBUTION OF THE BILATERAL SUBCORTICAL ZONE TO A BALANCE BETWEEN DIFFUSE BEHAVIORAL ACTIVATION AND SPECIFIC PSYCHOLOGICAL DIMENSIONS IS RAISED. (21 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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