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991.
Sotelo A Argote RM Moreno RI Flores NI Diaz M 《Journal of agricultural and food chemistry》2003,51(9):2821-2825
The nutritive and toxicological values of the dry seeds, germinated seeds, and string beans of Erythrina americana were studied using raw and boiled samples. Raw germinated seeds had a higher protein content and lower fiber content than dry seeds. The whole string bean had lower protein content and higher fiber content. However, the seeds of the green pod showed the same protein concentration as the dry seeds (dry basis). Boiling and elimination of broth was beneficial in diminishing the alkaloid concentration in all the samples. The trypsin inhibitors, lectins, and tannins were also diminished as was expected. The raw string bean showed the lowest LD(50). Although the total essential amino acids content of the boiled germinated seeds was increased, the quality of protein, protein efficiency ratio (PER), was lower than in boiled dry seeds, and in these, the PER was similar to the control (casein). The present results suggest that for the protein quality and low alkaloid content, the boiled dry seeds and string beans could be used for animal feeding. It could be interesting to test the raw string beans in ruminants since in this stage E. americana showed the lowest toxicity. 相似文献
992.
Janot‐Reine Mendler De Suarez 《Land Degradation \u0026amp; Development》2007,18(2):235-235
993.
Tolerance to zinc (Zn) deficiency was examined for three wheat (Triticum aestivum L.) and three barley (Hordeum vulgare L.) varieties grown in chelator‐buffered nutrient solution. Four indices were chosen to characterize tolerance to Zn deficiency: (1) relative shoot weight at low compared to high Zn supply (“Zn efficiency index”), (2) relative shoot to root ratio at low compared to high Zn supply, (3) total shoot uptake of Zn under deficient conditions, and (4) shoot dry weight under deficient conditions. Barley and wheat exhibited different tolerance to Zn deficiency, with barley being consistently more tolerant than wheat as assessed by all four indices. The tolerance to Zn deficiency in the barley varieties was in the order Thule=Tyra>Kinnan, and that of wheat in the order Bastian=Avle>Vinjett. The less tolerant varieties of both species accumulated more P in the shoots than the more tolerant varieties. For all varieties, the concentrations of Mn, Fe, Cu, and P in shoot tissue were negatively correlated with Zn supply. This antagonism was more pronounced for Mn and P than for Cu and Fe. Accumulation of Cu in barley roots was extremely high under Zn‐deficient conditions, an effect not so clearly indicated in wheat. 相似文献
994.
995.
J.‐M. Nicolau 《Land Degradation \u0026amp; Development》2003,14(2):215-226
This paper examines trends in topography design and construction in opencast mining restoration. The greatest geomorphological focus is the protection of aquatic ecosystems downstream of reclaimed sites through the construction of topographies and structures that not only reduce sediments and contaminants to a minimum, but which soften the impact of maximum water flows. From the ecological point of view, the most important focus is the integration of the geomorphological component with those of the soil and vegetation, and the formation of a functional ecosystem with the capacity to maintain itself. The conceptual models of relief that have been used in practice are discussed and criticized: these include the platform‐bank model (geotechnically but not ecologically stable), faithful reproduction of the original topography (inadequate in steep areas), and understanding the hydrological basin as a restoration unit (now considered the most appropriate). Finally, erosion models are reviewed as tools for relief design. The practicality of ‘RUSLE 1.06 for Mined Lands, Construction Sites and Reclaimed Lands’ is underlined owing to its ease of use. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
996.
Double‐null partial waxy wheat (Triticum aestivum L.) flours were used for isolation of starch and preparation of white salted noodles and pan bread. Starch characteristics, textural properties of cooked noodles, and staling properties of bread during storage were determined and compared with those of wheat flours with regular amylose content. Starches isolated from double‐null partial waxy wheat flours contained 15.4–18.9% amylose and exhibited higher peak viscosity than starches of single‐null partial waxy and regular wheat flours, which contained 22.7–25.8% amylose. Despite higher protein content, double‐null partial waxy wheat flours, produced softer, more cohesive and less adhesive noodles than soft white wheat flours. With incorporation of partial waxy prime starches, noodles produced from reconstituted soft white wheat flours became softer, less adhesive, and more cohesive, indicating that partial waxy starches of low amylose content are responsible for the improvement of cooked white salted noodle texture. Partial waxy wheat flours with >15.1% protein produced bread of larger loaf volume and softer bread crumb even after storage than did the hard red spring wheat flour of 15.3% protein. Regardless of whether malt was used, bread baked from double‐null partial waxy wheat flours exhibited a slower firming rate during storage than bread baked from HRS wheat flour. 相似文献
997.
X. Z. Xu H.‐W. Zhang G.‐Q. Wang Y. Peng O. Y. Zhang 《Land Degradation \u0026amp; Development》2006,17(6):629-644
The building of check‐dams is one of the most effective measures for the conservation of soil and water in the Loess Plateau of China, and the hydro‐sedimentologic balance is the most important factor influencing the relative stability of the check‐dam systems. This means that the soil and water in small watersheds controlled by the check‐dams will be absorbed internally, without the need for raising the height of the dams, if some given parameters have reached certain values. A runoff simulation experiment for a single check‐dam and a rainfall simulation experiment for the whole check‐dam system has been conducted, and the runoff/rainfall intensity and the parameter RV were determined through the annual erosion rate of the prototype watershed. The results indicated that the raising of the dam‐land altitude became slower, and the mean gradient of the gully was kept at a constant. The main reasons causing the check‐dam to show a good relative stability are the enlarging of the dam‐land area, the alleviating of erosion by the check‐dam, and the auto‐stabilizing mechanism of the gullies. This study presents a kind of scale‐down model experiment in which the ratio of the model geomorphological variable to the corresponding prototype variable keeps constant after the determinate runs of rainfalls, so that the soil and water erosion processes of the prototype could be monitored from the results of the model experiment. Four measures have been suggested for ensuring this ratio is a constant: (1) A bare‐land model with an appropriate erosion rate should be used in the experiment. (2) Dimensions of the landform, including the check‐dam, should normally be scaled down according to the prototype watershed. (3) Soil similar to those of the prototype should be used. (4) The antecedent water content before each rainfall simulation should be kept constant. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
998.
N. T. W. Cooper T. J. Siebenmorgen P. A. Counce J.‐F. Meullenet 《Cereal Chemistry》2006,83(4):447-450
Rice quality, specifically head rice yield (HRY), can vary inexplicably from one lot to another, and from year to year. In an effort to correlate air temperatures during various growth stages to HRY, growth staging data expressed in degree day units was used to predict the occurrence of sequential growth stages within a set of 17‐year historical data, which included HRY and 50% heading dates for two long‐grain rice cultivars, (Oryza sativa L) Newbonnet and Lemont, and area weather data. HRY was most strongly affected by the average daily low temperature (or nighttime temperature) during the R8 developmental stage. Lower HRY were associated with high nighttime air temperatures during this stage for both Newbonnet and Lemont. When used as a single variable in a regression model, the nighttime temperature during the R8 developmental stage explained over 25% of the variation in HRY. 相似文献
999.
The impact of extrusion on physical and sensory properties and on the in vitro bile acid (BA) binding was examined for N979 and Jim oat (Avena sativa) lines with 8.1 and 4.8% β‐glucan, respectively. Based on hardness and edibility of products made from Jim oats, moisture concentrations of 16–25% and temperatures of 165–180°C were selected for N979 extrusion. Jim‐based cereal had a significantly greater (P < 0.05) expansion ratio than did N979‐based cereal at most moistures. N979 cereal was browner, but not harder, than Jim cereal. Extruded products from N979 and Jim oats had 5.29–5.99% and 3.38–3.94% β‐glucan, respectively. Changing extrusion temperature or moisture content did not affect β‐glucan concentration in the products. N979 cereal made at 165°C and 16% moisture had greater BA binding than at other conditions, and had crunchiness comparable to cereals made at other conditions. BA binding of Cheerios brand breakfast cereal was close to that of N979 cereal made at 180°C and 18% moisture, but lower than cereals made at other conditions. Cereals made from Jim and N979 oats were browner, harder, coarser, and crunchier than Cheerios breakfast cereal. Proper processing and preparation techniques should be considered when producing extruded products from high β‐glucan oats. 相似文献
1000.
Generation of organic waste is increasing worldwide and strategies for its environmentally sound use must be developed and optimized. Regulations in European countries and the USA differ largely with respect to requirements of organic waste quality and the quantities of pollutants which can be added to the soil. Research has shown beneficial effects regarding the improvement of soil fertility. Enrichment of total metals in soil was attributed to long‐term sludge application but the effect on bioavailability of metals must be further clarified. A number of organic pollutants, such as hydrophobic persistent organic contaminants and surfactants, are known to accumulate in organic wastes. However, the former interact strongly with organic matter in the sludge‐soil‐plant system and systemic plant uptake is generally assumed to be minimal. Surfactants may cause adverse environmental impacts when they enter sewage systems in high loads and accumulate in sludge. Surfactants and some of their metabolites are not readily biodegraded in non‐aerated environments. Due to their toxicity and estrogenic activity, of nonylphenol for example, more research is needed to optimize analytical techniques and to trace their behavior in soil. Some options to cope with the risks of huge amounts of organic waste and also some benefits are presented: (1) further limitation of standards for pollutants and reduced application rates; (2) improved treatment of sewage sludge to reduce the total and bioavailable portions of both heavy metals and organic pollutants; (3) adaptation of waste application rates to soil properties such as sorption capacity for pollutants; (4) harmonization of analytical protocols for organic contaminants, i.e. surfactants and metabolites, enabling a more thorough monitoring of the wastes which are to be applied onto soils. 相似文献