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61.
Fractions rich in indigestible carbohydrates, such as fructan and arabinoxylan, are obtained as by‐products when ethanol, starch, and gluten are produced from wheat flour. Today, these fractions are used as animal feed. However, these components may have positive physiological effects in humans. In this study, the content of indigestible carbohydrates in distillers' grains and process streams from the wet fractionation of wheat flour was determined. The fractions were further characterized by ethanol extractability analysis, anion‐exchange chromatography, NMR, and size‐exclusion chromatography. One fraction from wet fractionation contained (g/100 g, db) 6.0 ± 1.0 fructan and 10.3 ± 1.1 dietary fiber (66 ± 4% arabinoxylan), while distillers' grains contained 20.7 g/100 g (db) dietary fiber (30% arabinoxylan). In addition to indigestible carbohydrates from wheat, distillers' grains contained β‐(1→3) and β‐(1→6) glucans and mannoproteins from the yeast and low molecular weight carbohydrates mainly composed of arabinose. The use of endoxylanase in wet fractionation decreased the molecular weight of the arabinoxylans and increased the arabinose to xylose ratio but had no effect on the fructans. In conclusion, waste streams from industrial wheat processing were enriched in fructan, arabinoxylan, and other indigestible carbohydrates. However, the physiological effects of these fractions require further investigation.  相似文献   
62.
Epidemiology and Integrated Control of Potato Late Blight in Europe   总被引:1,自引:0,他引:1  
Phytophthora infestans, the causal agent of late blight, is a major threat to potato production in northwestern Europe. Before 1980, the worldwide population of P. infestans outside Mexico appeared to be asexual and to consist of a single clonal lineage of A1 mating type characterized by a single genotype. It is widely believed that new strains migrated into Europe in 1976 and that this led to subsequent population changes including the introduction of the A2 mating type. The population characteristics of recently collected isolates in NW Europe show a diverse population including both mating types, sexual reproduction and oospores, although differences are observed between regions. Although it is difficult to find direct evidence that new strains are more aggressive, there are several indications from experiments and field epidemics that the aggressiveness of P. infestans has increased in the past 20?years. The relative importance of the different primary inoculum sources and specific measures for reducing their role, such as covering dumps with plastic and preventing seed tubers from becoming infected, is described for the different regions. In NW Europe, varieties with greater resistance tend not to be grown on a large scale. From the grower??s perspective, the savings in fungicide input that can be achieved with these varieties are not compensated by the higher (perceived) risk of blight. Fungicides play a crucial role in the integrated control of late blight. The spray strategies in NW Europe and a table of the specific attributes of the most important fungicides in Europe are presented. The development and use of decision support systems (DSSs) in NW Europe are described. In The Netherlands, it is estimated that almost 40% of potato growers use recommendations based on commercially available DSS. In the Nordic countries, a new DSS concept with a fixed 7-day spray interval and a variable dose rate is being tested. In the UK, commercially available DSSs are used for c. 8% of the area. The validity of Smith Periods for the new population of P. infestans in the UK is currently being evaluated.  相似文献   
63.
Leaching of phosphorus (P) from agricultural land is a major contributor to eutrophication of surface waters in many countries, and effective mitigation options to reduce P in leachate are needed. In this study, intact columns (0.77 m deep) of subsoil from three Swedish agricultural soils (one sand and two clay) were used to examine whether placing quicklime (calcium oxide, CaO) on the subsoil could reduce P leaching over a 3‐yr period. Leaching of particulate P (PP) was significantly less from clay soil columns with lime than from clay soil columns without (P < 0.001 and P < 0.05, respectively), with a relative reduction of 49 and 51% in the two soils. Leaching of dissolved reactive P (DRP) was less from sand columns with lime than from sand columns without, although not significantly so due to large variation in P leaching between columns. These results indicate that placement of lime on subsoil has potential to reduce P leaching, especially of PP from clay soils. However, more studies including both topsoil and subsoil and a range of soil types are needed to assess the full potential of this P mitigation option.  相似文献   
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Stream waters were sampled weekly during spring and monthly during summer and autumn in 1998. The streams are more or less acidified, and some have been treated with lime. The aluminium fractions (total monomeric Al, organic monomeric Al, inorganic monomeric Al) were determined colourimetrically with pyrocatechol violet combined with cation exchange using Continuous Flow Analysis (Autoanalyzer I). The levels of inorganic monomeric aluminium varied substantially, between <3 to 271 µg/l. The levels were higher in untreated than in limed waters and twice as high in the most humic waters as in less humic waters. The importance of aluminium mobilisation from the catchments was obvious, with higher aluminium concentrations in surface runoff (unbalanced stream waters) compared to lake outlets (balanced and precipitated lake water). The highest mean levels were measured at spring, whereas the highest single peaks occurred during summer. Inorganic monomeric and total monomeric aluminium was best correlated to ion ratio and pH whereas acid soluble aluminium and organic monomeric aluminium was best correlated to TOC, water colour and iron.  相似文献   
66.
Two systems for enrichment and collection of natural Zooplankton in cooling water recipients were developed for rearing fish fry. One system filters-off plankton from the cooling water with rotating dip-nets (diam. 60 cm). The rotation is powered by the kinetic energy of the water and the nets are continuously flushed clean by high-pressure sprays. The water from the nets, being enriched with plankton, is pumped continuously to a grading station where undesirable size fractions are removed, after which the water is distributed to the rearing pens. The system has been tested at a nuclear power station in the south-western part of the Bothnian Sea and found to be promising, with a collection of, on average, 280 g day–1. The other system is based on attraction using underwater lamps and pumping of organisms into floating rearing pens. The system is automatic and powered by electricity from the grid. The technical performance has been good. The plankton has been size-graded by attaching net baskets around the lamps. At a nuclear power station on the western coast of the central Baltic Sea, the amount collected has, on average, been 45–570 g Zooplankton lamp–1 night–1. The collection system is considered to be of use in productive areas with moderate turnover of water. Both systems are in early stages of development and have not reached their full potential. Improvements are proposed and discussed.  相似文献   
67.
Maturing male and female Atlantic salmon (Salmo salar L.) were held under three temperature regimes for 10 weeks between September and December: warm (constant 14–16 °C), ambient (decreasing from 11 to 5 °C), and cold (decreasing from 7 to 3 °C). Blood samples were analyzed for plasma steroid levels, and the fish were inspected for the presence of expressible milt (total volume and spermatocrit) and ovulation weekly. Samples of eggs were dry-fertilized with milt stripped from three males held at the same temperatures and incubated until the eyed stage. In females, levels of plasma testosterone (T) and 17β-oestradiol (E2) dropped as ovulation approached, concurrent with a rapid increase in levels of plasma 17α,20β-dihydroxy-4-pregnen-3-one (17,20β-P). In males, levels of T and 11-ketotestosterone (11-KT) peaked 2–3 weeks after the first appearance of expressible milt, while levels of 17,20β-P increased steadily and did not exhibit a definite peak. Exposure of females to cold water amplified and advanced the profiles of all three steroids compared with the ambient group, and increased the survival rates to the eyed egg stage. Cold water had no immediate effect on the male steroid profiles, but later, higher levels of 17,20β-P were evident compared with both the ambient controls and the warm water group, while the effects on 11-KT and T were more variable. Exposure to warm water completely inhibited both milt production and ovulation. Moreover, warm water modulated the steroid profiles of the males with lower 11-KT levels compared with ambient controls and lower 17,20β-P level compared with cold-water-treated males. In females, warm water resulted in total inhibition of the peri-ovulatory peak in 17,20β-P and prevented the normal decline of T and E2 levels associated with ovulation. The findings of the present study are highly relevant for broodstock management in aquaculture, as well in understanding the impact of climate change/temperature variability on wild salmon spawning.  相似文献   
68.
Bali cattle still represents 27% of the total cattle population in Indonesia, and it is considered the pillar breed for small farmers. Moreover, it is a breed of evolutionary importance regarding its direct ancestry from Banteng. However, there is a need for the establishment of a rational system for the evaluation of breeding soundness for indigenous Bali bulls to be used as sires for artificial insemination breeding programmes. Moreover, there is a need for cryobanking of well-identified genetic resources pertaining their use in evolutionary research and application as essential germplasm in breeding programmes.  相似文献   
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