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71.
Dannenberger D Nuernberg G Scollan N Ender K Nuernberg K 《Journal of agricultural and food chemistry》2007,55(2):452-460
The objective of this study was to investigate the effect of diet on the distribution of phospholipid classes and fatty acid profiles of individual phospholipid classes in longissimus muscle of beef. An experiment was established to examine the effect of pasture-based versus concentrate diet offered to two different breeds (German Holstein and German Simmental bulls) to enhance the content of beneficial fatty acids in beef and improve the meat quality for the consumer. High-performance thin-layer chromatography was utilized to separate the phospholipid classes. The fatty acid composition of the individual phospholipid classes was determined by gas chromatography. The main phospholipid classes in the muscle were phosphatidylethanolamine and phosphatidylcholine, representing approximately 60% of the total phospholipids, followed by phosphatidylinositol ranging between 11.8 and 14.8%. The results have shown that the fatty acid profiles in the detected seven phospholipid classes can be affected by different feeding systems. Pasture-based feeding resulted in an enrichment of total and individual n-3 fatty acids in all phospholipid classes of muscle lipids of bulls compared with those fed on concentrate. In contrast, pasture-based diet significantly decreased the proportion of total and individual n-6 fatty acids in phospholipid classes, except in the sphingomyelin fraction. The total saturated fatty acid proportions in the phospholipid classes were different and ranged between 4.5% in the cardiolipin fraction and 50.5% in the sphingomyelin fraction of muscle lipids of bulls. Furthermore, the diet effects on the saturated fatty acid proportion in the different phospholipid classes differ widely. The results have shown that the C18:1 trans and CLA profiles in the detected seven phospholipid classes can be affected by different feeding systems. 相似文献
72.
Gerd Wegener 《Euphytica》1996,90(2):iii-v
Editorial: a warm welcome to Professor Dr. Evert Jacobsen, new Editor-in-Chief and retrospections on thirty years of editorship 相似文献
73.
Site characteristics and hydrology of sealed aereas Soil physical and chemical properties of typical sealed urban sites in Berlin were measured. Water components were determined using lysimeters with differently sealed surfaces. Water storage and infiltration is small and depends on sealing materials. Evapotranspiration and drainage are reduced whereas runoff is increased. During summer time high surface temperatures might occur on sealed surfaces. Because of high dust input, infiltration of old sealed sites is reduced by an order of magnitude compared to sites which have been sealed recently. Long-term input of dust resulted in an increase of clay, silt, organic material and heavy metals. Finally specific recommendations for land planners are given. 相似文献
74.
Determination of bulk density in stony soils A new method is represented which makes it possible to measure the bulk density easily even in the case of stony soils. First results demonstrate the reliability of this new method. 相似文献
75.
Ametaj BN Bobe G Lu Y Young JW Beitz DC 《Journal of agricultural and food chemistry》2003,51(8):2105-2110
The objective was to evaluate the effect of sample preparation (pulverization under liquid nitrogen, homogenization, or sonication), time length of sonication (0-60 s), shaking in chloroform/methanol solvent (0, 2, 4, or 12 h), incubation in chloroform (0 or 12 h), and drying of extracted lipids at 50 degrees C (2, 4, 6, or 24 h), and sample size (50-250 mg) on quantification of total lipids from bovine liver. Pulverization under liquid nitrogen yielded the lowest recovery. Sonication was least time-consuming for sample preparation. Precise estimates and the greatest recovery were obtained with 30 s of sonication, at least 2 h of shaking in chloroform/methanol solvent, 12 h of incubation in chloroform, and at least 6 h of drying. Sample sizes of at least 150 mg gave precise estimates. The results demonstrate that sample preparation, time length of different steps of the extraction procedure, and sample size affect quantification of total lipid from bovine liver. 相似文献
76.
Gerd Palm 《Erwerbs-Obstbau》2011,53(3):107-118
Faced with a large diversity of pests and diseases of regular or variable importance to fruit production, the Plant Protection Section has to deliver timely disease forecasts and decisions concerning potential control measures. The main strength of the Plant Protection Section has been a functional experimental set-up which lays an important foundation for the regional advisory service. Applied research has been a basis for developments in crop protection in the Lower Elbe region. Thus, crucial prerequisites for the introduction of Integrated Crop Protection have been established and further developed, always looking for solutions to existential problems. Problems in controlling of apple sucker and apple scab led to the establishment of the Fruit Experiment Station (OVA) Jork. Existential threats in subsequent years were posed by a large number of pests and diseases, including water voles and bitter rot in apple production, and fire blight, tree decline and little-cherry in sweet cherry production. Specific legislation covering the special fruit production area??Altes Land?? has been a milestone in securing the future of regional fruit production. Along similar lines, comprehensive surveys of the behaviour of crop protection compound residue have been conducted recently, the results being used as arguments against scientifically unfounded demands by food retailers concerning limitations of the number of detectable residues. The Plant Protection Section will continue to play a crucial role in the Fruit Experiment Station. Future challenges have to be met by a highly motivated and well equipped team. 相似文献
77.
Europe's terrestrial biosphere absorbs 7 to 12% of European anthropogenic CO2 emissions 总被引:2,自引:0,他引:2
Janssens IA Freibauer A Ciais P Smith P Nabuurs GJ Folberth G Schlamadinger B Hutjes RW Ceulemans R Schulze ED Valentini R Dolman AJ 《Science (New York, N.Y.)》2003,300(5625):1538-1542
Most inverse atmospheric models report considerable uptake of carbon dioxide in Europe's terrestrial biosphere. In contrast, carbon stocks in terrestrial ecosystems increase at a much smaller rate, with carbon gains in forests and grassland soils almost being offset by carbon losses from cropland and peat soils. Accounting for non-carbon dioxide carbon transfers that are not detected by the atmospheric models and for carbon dioxide fluxes bypassing the ecosystem carbon stocks considerably reduces the gap between the small carbon-stock changes and the larger carbon dioxide uptake estimated by atmospheric models. The remaining difference could be because of missing components in the stock-change approach, as well as the large uncertainty in both methods. With the use of the corrected atmosphere- and land-based estimates as a dual constraint, we estimate a net carbon sink between 135 and 205 teragrams per year in Europe's terrestrial biosphere, the equivalent of 7 to 12% of the 1995 anthropogenic carbon emissions. 相似文献
78.
Gerd Junne 《Agriculture and Human Values》1993,10(2):40-46
The predominant position of large companies, while crucial for the acceptance of biotechnology, at the same time slows down the pace of biotechnological development and application. Large agrochemical and food processing companies are characterized by a number of internal barriers against applications of biotechnology in agriculture. They also show a greater sensibility to the external barriers than many small companies. Their takeover of agricultural biotechnology, therefore, has led to a more evolutionary than revolutionary development.Gerd Junne holds the Chair in International Relations at the Social Sciences Faculty of the University of Amsterdam in The Netherlands. His current research addresses strategies of multinational enterprises, changes in the international division of labor, and the impact of new technologies. He has been the editor of theBiotechnology and Development Monitor, published by the University of Amsterdam and the Dutch Ministry of Foreign Affairs. 相似文献
79.
Contribution of bricks to urban soil properties 总被引:3,自引:2,他引:1
Thomas Nehls Sarah Rokia Beate Mekiffer Christophe Schwartz Gerd Wessolek 《Journal of Soils and Sediments》2013,13(3):575-584
Purpose
Bricks are regularly found in urban soils where they can strongly impact soil properties. The purpose of this study is to investigate abundance, especially in the fine earth fraction, and properties of bricks in urban soils, focusing on rooting, plant nutrition and contamination.Materials and methods
Three different urban soils from the city of Berlin have been studied for their brick contents in the coarse and fine earth fractions by hand sorting. Light (LM) and scanning electron microscopy (SEM) was employed to investigate bricks for proofs of rooting. Third, CEC, pH, EC, Corg, nutrient and contaminant storage and availability have been investigated for bricks and the fine earth fractions of the corresponding soil horizons.Results and discussion
The fine earth fractions of the investigated soils contain 3 to 5 % of bricks, while the coarse fractions contain up to 50 %. The LM and SEM micrographs made the proof that roots enter brick pores or attach to brick surfaces. Therefore, they can use the water and nutrients stored in bricks and bypass pore system discontinuities between bricks and surrounding soil. The CEC of bricks is grain size dependent and reaches a maximum of 6 cmolc kg?1 for particles smaller than 0.063 mm. This dependency is the result of the restricted diffusion into the brick pore system due to the short shaking time in the CEC analysis protocol and of the rising surface with decreasing particle size. From the nutrient storage and availability, we conclude that bricks can better supply plants with K, Mg, Ca and S than the investigated sandy bulk soil.Conclusions
The nutrient availability from bricks is low compared to control soils, except for Ca and S. Because of the water and nutrient storage, low contamination status and the possible rooting of bricks, they can be used for amelioration of poor sandy soils and for constructed Technosols, preferably employed in small grain sizes. 相似文献80.
IUSS SUITMA 6 International Symposium 2011 总被引:1,自引:1,他引:0