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21.
An alternative to the use of synthetic pesticides is to exploit the natural defense chemicals produced by cereals. An important class of allelochemicals is cyclic hydroxamic acids and related benzoxazolinones. A prolonged degradation experiment of the allelochemical compound from rye 2-benzoxazolinone (BOA) was carried out for up to 90 d at 15°C at three different concentration levels, 3, 3000, and 30,000 nmol BOA· g soil–1, respectively, in a sandy loam soil. Two main degradation products, 2-amino-(3H)-phenoxazin-3-one (APO) and 2-acetylamino-(3H)-phenoxazin-3-one (AAPO), were identified and quantified by LC-ESI-MS-MS. The half-life of BOA increased with higher levels of BOA added to the soil. Half-lives of BOA, APO, and AAPO were determined by fitting a single first-order model to the degradation data. Half-life of BOA was determined to be 0.6 d in the 3 nmol BOA g soil–1 treatment. Half-lives of BOA, APO, and AAPO were 3.1, 2.7, and 2.1 d, respectively, in the 3000 nmol BOA· g soil–1 treatment. In the 30,000 nmol BOA· g soil–1 treatment, the half-lives were 31 d for BOA and 45 d for APO. The microbial community structure was not affected by addition of BOA to the soil as investigated by analysis of signature fatty acids. The results suggest that the exploitability of BOA for crop protection is dependent on the existing concentration of BOA in the soil and the timing of incorporation of hydroxamic acid synthesizing crops into the soil. 相似文献
22.
The smart grid is promoted as one of the key elements in a low-carbon transition in many countries. In Denmark, the dominant framing of the smart grid emphasises the challenge of integrating much more wind power into the electricity system and using electricity for heating (heat pumps) and transport (electric cars). In the process of radically transforming the electricity system, strategic system builders need to align many forces, including consumers, who play an important role in the functioning of such large networked systems. System builders need to explore, for instance, whether and how users can be motivated to be flexible in relation to moving electricity consumption over time. This paper reports on one of the first smart-grid-related projects in Denmark in which consumer aspects have been central and where potentials for flexible electricity consumption have been tested. The aim of the paper is to explore what can be learned from such experiments and which roles they play in the construction of the smart grid. In this context, the concept of the ‘aligned user’ is introduced. 相似文献
23.
24.
The article deals with the issues related to the implementation of EU greenhouse gas (GHG) emission trading scheme in Baltic States. The main objectives of the article are to analyse the main features and requirements of EU emission trading scheme and to assess the results of the first trading GHG trading period based on verified GHG emissions in Baltic States. The main aim of the article is to compare GHG emission trading results among Baltic States and provide with some insights for the next GHG trading period and assess possible implications on energy sector of Lithuania, Latvia and Estonia. 相似文献
25.
This article deals with external cost of electricity generation in Baltic States. The costs of electricity generation and distribution are the most important criteria shaping decisions within the electricity system. However, the external cost due to air pollution should also be adequately taken into account seeking to promote new and clean technologies for electricity generation. External costs of electricity generation in the main power plants burning fossil fuel were calculated based on ExternE methodology for Baltic States during EU Framework 6 project CASES. The article presents the first results of external cost of electricity generation in Baltic States. 相似文献
26.
27.
J. W. Blankenship C. M. Van Gent L. B. Sandberg P. J. Roos J. A. Scharffenberg 《Lipids》1991,26(5):381-384
The incorporation of dietary cholestan-3β, 5α, 6β-triol (triol) into rat thoracic aortic tissue and changes in amino acid
composition of the elastin were investigated to identify the cytotoxic properties of the triol. Weanling male Sprague-Dawley
rats were fed the following diets for three months: (i) normal chow, (ii) normal chow with 1% (w/w) cholesterol added, or
(iii) normal chow with 0.9% (w/w) cholesterol and 0.1% (w/w) triol added. Triol levels in the blood and in the thoracic aortic
tissue were measured. Compositional changes of elastin were also determined. After three months on the triol-containing diet,
triol was found in the thoracic aorta but was not detected in the blood. Amino acid analyses of the aortic tissue elastin
revealed that the proline levels in the triol-fed animals were significantly greater than in the other two diet groups, while
the elastin levels of leucine, aspartate, arginine, and phenylalanine decreased significantly. The mechanism for these observed
changes induced by triol may reflect alternate splicing of elastin messenger ribonucleic acid (mRNA) resulting in structural
changes in the elastin molecule. Dietary triol does contribute to tissue triol content and is associated with aortic elastin
compositional changes. How these changes may contribute to the development of cardiovascular disease is not known. 相似文献
28.
Urine and preputial gland secretion of male bank voles were analyzed by gas chromatography (GC) and mass spectrometry (MS) (selected ion monitoring, SIM). GC-MS analyses showed the presence of hexadecyl acetate in preputial gland secretion and in marking urine but not in metabolic urine. Female bank voles responded more strongly to marking urine of males than to metabolic urine, and they responded more to preputial gland secretion (pure or added to urine) than to metabolic urine. Dominant males spent more time and marked more frequently in response to hexadecyl acetate-enriched urine than to urine alone. The opposite reaction was shown by subordinate males. The results suggest that the acetate functions in the bank voles' dominance interactions. 相似文献
29.
Airi Mäkinen Inge de Wreede Hermann Stegemann und Hans Heinz Heinert 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,168(4):282-285
Zusammenfassung Das Lösungsvermögen des Anionendetergents Na-dodecylsulfat (SDS) in Gegenwart disulfidbrückenspaltender Reagentien auf native und auf hitzedenaturierte Proteine wird an Fleisch-und Kartoffelproteinen mit Hilfe elektrophoretischer Methoden untersucht. Die zur Resolubilisierung notwendige Menge an SDS und die erforderliche Incubationszeit werden für die verschiedenen Proben ermittelt. Die Proteine des Skeletmuskels von Rind, Schwein, Huhn und Pute einerseits und die Proteine der europäischen Kartoffelsorten und der südamerikanischen Primitivkultivare andererseits zeigen in der SDS-PAGE ein sehr ähnliches Bandenmuster, das speziesdifferenzierend kaum ausgewertet werden kann, aber ein gutes Charakteristikum für Muskel-bzw. Kartoffelproteine ist.
Diese Arbeit ist Teil der Dissertation von I. de Wreede. Die Analyse der tierischen Proteine bearbeitete I. de Wreede.Sonderdruckanfragen an: I. de Wreede (Adresse siehe oben) 相似文献
Solubility and electrophoretic patterns of heat-denaturated proteins (including samples containing starch) after treatment with SDS (sodiumdodecylsulfat)
Summary The ability of the anionic detergent SDS (sodium-dodecylsulfate) to solubilize native and heat-denaturated proteins of meat and potatoes in presence of disulphide reducing agents was checked by electrophoretic methods. Skeletal muscle proteins of beef, pork, chicken and turkey have shown very similar patterns in SDS-gelelectrophoresis, which could hardly be used for species identification but they are characteristic for fresh or boiled muscles. Proteins of European potato cultivars and primitive cultivars from South America have almost identical SDS-patterns even if taken from boiled potatoes. Their patterns are different from the proteins of other European crops plants and may serve for detection of the presence of potatoes in food mixtures.
Diese Arbeit ist Teil der Dissertation von I. de Wreede. Die Analyse der tierischen Proteine bearbeitete I. de Wreede.Sonderdruckanfragen an: I. de Wreede (Adresse siehe oben) 相似文献
30.
Beatrice Ekesa Marie Poulaert Mark W. Davey Judith Kimiywe Inge Van den Bergh Guy Blomme Claudie Dhuique-Mayer 《Food chemistry》2012
Bananas and plantains (Musa spp.) constitute an important component of the diet in Africa. Substantial levels of provitamin A carotenoids (pVACs) in Musa fruit have been reported, but the bioaccessibility of these pVACs remains unknown. In this study, we used an in vitro digestion model to assess the bioaccessibility (i.e. the transfer into micelles) of pVACs from boiled bananas and derived dishes using the Eastern Democratic Republic of Congo as a study context. In particular, the effect of different food ingredients added to boiled bananas on pVAC’s bioaccessibility was studied. The bioaccessibility of all-trans β-carotene ranged from 10% to 32%, depending on the food recipes, and was modified, particularly when pVACs-rich ingredients (palm oil/amaranth) were added. Efficiency of micellarization of all-trans β-carotene was similar to that of all-trans α-carotene and depended on the cultivar (Musilongo, plantain type, 16%; Vulambya, East African cooking type, 28%), while that of the 13-cis isomer was higher (21–33.5%). Taking into account bioaccessibility, the estimated vitamin A activity was significantly different across the different Musa-based dishes tested. Results are discussed in terms of recommendations to help reduce vitamin A deficiency in Musa-dependent African communities. 相似文献