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111.
Alzheimer’s disease (AD) is a degenerative brain disorder characterized by a progressive decline in memory and cognition, mostly affecting the elderly. Numerous functional bioactives have been reported in marine organisms, and anti-Alzheimer’s agents derived from marine resources have gained attention as a promising approach to treat AD pathogenesis. Marine sterols have been investigated for several health benefits, including anti-cancer, anti-obesity, anti-diabetes, anti-aging, and anti-Alzheimer’s activities, owing to their anti-inflammatory and antioxidant properties. Marine sterols interact with various proteins and enzymes participating via diverse cellular systems such as apoptosis, the antioxidant defense system, immune response, and cholesterol homeostasis. Here, we briefly overview the potential of marine sterols against the pathology of AD and provide an insight into their pharmacological mechanisms. We also highlight technological advances that may lead to the potential application of marine sterols in the prevention and therapy of AD.  相似文献   
112.
The effect of two lipases and DATEM at different concentrations on the rheological and thermal properties of white and whole wheat flour doughs was determined by farinograph, extensograph, texture analyzer and differential scanning calorimetry. Lipases provided similar or better results than that of DATEM on decreasing softening degree and stickiness, and increasing stability, maximum resistance to extension and hardness. Extensibility and energy did not change with lipases, but decreased with DATEM. Lipases and DATEM slightly modified the transition temperatures and enthalpies of ice-melting and starch gelatinization, but significantly increased the moisture and unfrozen water contents, and decreased the solid concentration in unfrozen water. The greatest effect of lipases was observed on decreasing the peak temperature and increasing the enthalpy of amylose–lipid complex dissociation. The changes in the rheological and thermal properties were almost independent of the concentration levels tested, and were mostly reduced when whole wheat flour was used. The improvement in the dough properties by lipases is possibly related to the in situ formation of surface active compounds from endogenous flour lipids. Presumably, these compounds are already located in the right positions in dough, where they might have higher interaction potentials than DATEM with the dough components.  相似文献   
113.
Twelve wheat varieties were studied for their phytic acid, calcium, iron, zinc, copper and phosphorus contents, which respectively ranged between 114–166, 25.1–53.5, 3.41–5.55, 0.71–3.00, 0.65–1.32 and 298–314 mg/100 g. The molar ratios as Ca:Phy, Phy:Fe, Phy:Zn, Phy:Cu were found to be 0.14–0.29, 1.96–3.86, 5.11–20.5 and 13.0–23.9, respectively. Significant dephytinization, ranging between 35.3 and 69.3% in different varieties, was achieved on exogenous enzymatic treatment. Enzymatic dephytinization in the in vitro simulated gastrointestinal digestion resulted in significant increase in the bioavailability of essential minerals. The increase in bioavailability of calcium, iron, zinc and copper on exogenous enzymatic dephytinization ranged between, respectively (x-folds): 1.30–1.96, 1.11–1.52, 1.22–1.78 and 1.11–1.73.  相似文献   
114.
Shi drum (Umbrina cirrosa L.) is regarded as a promising new candidate for Mediterranean mariculture but specifically formulated feeds are not yet available due to knowledge gaps in its basic nutritional requirements. Therefore, this study was carried out to determine the effects of dietary lipid levels on growth and feed utilization in shi drum (72.6 g average weight). Four isonitrogenic diets differing in dietary lipid levels between 10 and 19% (named 10L, 13L, 16L, and 19L, respectively) were fed to triplicate groups of fish for 8 weeks. Growth was not affected by treatment whereas feed efficiency was significantly deteriorated in fish fed diets containing lipid higher than 13%. Whole body dry matter and lipid contents were significantly higher in fish fed 19L compared with fish fed the 10L, while whole body protein, ash, and total carbon (C) were statistically unaffected by the dietary treatment. A significant increase in feed, lipid, energy, nitrogen (N), and carbon (C) intake was recorded in fish fed 16L and 19L when compared with 10L. Carbon/nitrogen (C/N) ratio was significantly higher in fish fed 19L than 10L. Moreover, the N and C losses significantly increased in fish fed 19L compared with 10L and 13L. It was concluded that high dietary lipid did neither had any protein-sparing effect nor other positive result, and diets for shi drum are not recommended to contain more than 13% lipid.  相似文献   
115.
This research was conducted to quantify total phosphorus (TP) losses in poorly drained-consolidated paddy fields equipped with different surface and shallow subsurface drainage systems including drain depth of 0.9 m and drain spacing of 30 m (D0.9L30), drain depth of 0.65 m and drain spacing of 30 m (D0.65L30), drain depth of 0.65 m and drain spacing of 15 m (D0.65L15), drain spacing of 15 m and drain depths of 0.65 and 0.9 m as alternate depths (Bilevel). Typical surface drainage system of consolidated paddy fields was also considered as conventional practice of the study area (control). The subsurface drained fields were under year-round crop production of rice-canola, while the surface drained fields experienced only rice cropping once a year. During three rice-canola-rice growing seasons, TP losses through drainage and leaching in the D0.9L30, Bilevel, D0.65L30, D0.65L15 and control treatments were respectively, 1.12, 0.98, 1.44, 1.53 and 24.48 kg ha?1, equivalent to about 3.9%, 3.4%, 5.1%, 5.3% and 85.7% of applied triple superphosphate fertilizer. In the rice growing seasons, TP losses through surface runoff were higher than those through subsurface drainage effluents. Shallow subsurface drainage systems were promising for the study area compared surface drainage as phosphorus risks were reduced by 79%, 77%, 64% and 57% through D0.9L30, Bilevel, D0.65L30 and D0.65L15, respectively. These results demonstrated that, by providing suitable condition for winter cropping, subsurface drainage systems can diminish concerns related to phosphorus losses from poorly drained paddy fields in the north of Iran.  相似文献   
116.
Information is key in reducing the uncertainties of sustainable agricultural practices (SAPs). The objective of this study was to improve the understanding of the relationship between utilized informational sources and other key identified factors affecting Malaysian vegetable producers' choices. The findings of a multivariate probit model suggest that information sources are complementary. The choices for these sources are influenced by heterogeneity in access to credit, social network (member of farmers association), and farm settings (distance from farm to market, resource depletion issues, and geographical regions). Future promotion of SAPs should be delivered through the provision of quality content disseminated through the preferred information sources, which target potential users.  相似文献   
117.
118.
Teak plantations date back to 1871 in Bangladesh.This study was designed to assess how teak monoculture has impacted the soil properties in Bangladesh.Multiple linear regression and correlation matrices were estimated to evaluate these impacts.The means of soil physicochemical properties were compared across various attributes of the plantations.Older plantations accumulated more organic carbon in the soils than the younger plantations.Excessive removal of litter from the forest floor resulted in reduced levels of N, P, K, and other nutrients in the soils.Since bulk density was continuously decreasing deeper into the soil, the penetration of mineral nutrients into the soil was low.Furthermore, moisture content in the topsoil was significantly lower than that in the bottom layers due to the exposed and dry condition of the forest floor under teak plantations.For improving depleted teak plantation soils, teak could be planted with other tree species rather than just in monocultures.In addition, the forest floor could be enriched with leguminous herbs and shrubs to improve soil health in these plantations.  相似文献   
119.
Forest roads require important design specifications to ensure all-season access for various vehicles. Long and heavy log trucks can face serious maneuvering problems on forest roads due to insufficient amount of area to the left for road widening on horizontal curves. In order to provide safe and continuous shipment and transportation,appropriate curve widening areas should be provided for long vehicles along horizontal curves. In this study, a statistical model was developed to provide curve-widening solutions for long trucks(e.g., those with 18 wheels) considering various curve radius and deflection angles. The dynamic curve widening feature of Plateia 2013 program was employed to calculate curve widening for the specified vehicle. During the solution process, nine different horizontal curve diameters from 10 to 50 m(by 5 m intervals)and 17 different deflection angles from 90° to 170°(by 5°intervals) were evaluated to run horizontal curve-widening analysis. Using a multiple regression model, we made suitable predictions about curve widening. The curvewidening areas decrease as the horizontal curve radius increases, while increasing the deflection angle on horizontal curves increases curve widening areas. Clearly, the computer-based dynamic curve widening model developed in this study can be effectively used in determining optimum widening for horizontal curves by evaluating the number of alternatives that fit geometrical specifications and vehicle types.  相似文献   
120.
To study the effect of foliar application of urea fertilizer on the growth and yield of tomato and to find out the optimum concentration of foliar application of urea for maximum growth and yield of tomato, an experiment was conducted with different concentrations of foliar application of urea fertilizer, namely, 2500, 5000, 7500, and 10000 ppm. The experiment was laid out by a randomized complete block design (RCBD) with four replications. Results showed that different yield components and yield of tomato were influenced by the foliar application of different concentrations of urea. The maximum plant height (132.6 cm), number of leaves (30.73), number of green leaves per plant at harvest (21.08), days to first flowering (28.94), number of flower clusters (11.89), number of flowers (75.18), fruit clusters (5.81), fruits per cluster (4.14), and fruits per plant (21.49); length (4.72 cm), diameter (6.58 cm), and weight of individual fruit (151.0 g) were significantly influenced by the 10000 ppm concentration of foliar application of urea fertilizer. The 10000 ppm application gave the highest yield (63.69 t/hm2) with the lowest (28.48 t/hm2) in the control treatment. The yield per plant as well as per hectare increased with increasing concentrations of foliar application of urea fertilizer.  相似文献   
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