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31.
Throughout the short history of industrial ecology, issues of implementation have been heavily emphasized. Less attention has been given to the ways in which the technical models of industrial ecology interact with social processes. Yet the practitioners of industrial ecology frequently encounter challenges pertaining to contextualization when embedding a general model in different local contexts. In addition, there are reasons to believe that the models of industrial ecological systems become politically meaningful only when they are carefully contextualized and linked to localized needs. In this article, we aim at a better understanding of the political embedding of industrial ecology. In order to demonstrate some general mechanisms of embedding, we first conduct a frame analysis of complex utilization—a scientific policy instrument analogous to industrial ecology, developed in the Kola Peninsula, Russia. We identify five frames in which complex utilization has been promoted between 1935 and 2005. These frames are then compared to six frames identified in the industrial symbiosis in Kalundborg, Denmark. We find that effective political embedding relies on frames that function both on a general level and in specific contexts. General frames, such as efficiency, economy, and environment, need to be aligned with localized perceptions of particular issues. What is more, sensitivity to purely context-specific frames is necessary for effective political embedding. Finally, the political processes of framing also shape the scientific-technical models that are being promoted.  相似文献   
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Local adaptation of interacting species to one another indicates geographically variable reciprocal selection. This process of adaptation is central in the organization and maintenance of genetic variation across populations. Given that the strength of selection and responses to it often vary in time and space, the strength of local adaptation should in theory vary between generations and among populations. However, such spatiotemporal variation has rarely been explicitly demonstrated in nature and local adaptation is commonly considered to be relatively static. We report persistent local adaptation of the short‐lived herbivore Abrostola asclepiadis to its long‐lived host plant Vincetoxicum hirundinaria over three successive generations in two studied populations and considerable temporal variation in local adaptation in six populations supporting the geographic mosaic theory. The observed variation in local adaptation among populations was best explained by geographic distance and population isolation, suggesting that gene flow reduces local adaptation. Changes in herbivore population size did not conclusively explain temporal variation in local adaptation. Our results also imply that short‐term studies are likely to capture only a part of the existing variation in local adaptation.  相似文献   
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Although the indigo reduction process is performed via natural fermentation and maintained under open-air condition, the indigo-reducing reactions continue for 6 months (on average) or longer. Identifying the mechanism underlying the maintenance of this process could lead to the development of a novel, long-lasting, unsterilized bioprocesses. To determine the mechanisms underlying the maintenance of the indigo fermentation system microbiota for more than 6 months in a reduced state in an anaerobic alkaline environment, we examined changes in the microbiota in one early-phase batch and two aged batches of indigo fermentation fluid. The microbiota in the aged fermentation fluid consisted mainly of the genera Alkalibacterium, Amphibacillus, Anaerobacillus and Polygonibacillus and the family Proteinivoraceae. The genera Alkalibacterium, Amphibacillus and Polygonibacillus are known to include indigo-reducing bacteria. Although the transition speed was slower in the aged fermentation fluid than in the early-stage fluid, the microbiota in the aged fermentation fluid maintained for more than 6 months was drastically changed within a period of 3 months. The results of this study indicate that the bacterial consortia consisted of various indigo-reducing species that replace the previous group of indigo-reducing bacteria. The notable transitional changes may be concomitant with changes in the environmental conditions, such as the nutritional conditions, observed over 3 months. This flexibility may lead to important changes in the microbiota that allow for the maintenance of a fermentation-reducing state over a long period.  相似文献   
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Collagen XVIII is characterized by three variant N termini, an interrupted collagenous domain, and a C-terminal antiangiogenic domain known as endostatin. We studied here the roles of this collagen type and its variant isoforms in the mouse kidney. Collagen XVIII appeared to be in a polarized orientation in the tubular basement membranes (BMs), the endostatin domain embedded in the BM, and the N terminus residing at the BM-fibrillar matrix interface. In the case of the glomerular BM (GBM), collagen XVIII was expressed in different isoforms depending on the side of the GBM. The orientation appeared polarized here, too, both the endothelial promoter 1-derived short variant of collagen XVIII and the epithelial promoter 2-derived longer variants having their C-terminal endostatin domains embedded in the BM and the N termini at the respective BM-cell interfaces. In addition to loosening of the proximal tubular BM structure, the Col18a1(-/-) mice showed effacement of the glomerular podocyte foot processes, and microindentation studies showed changes in the mechanical properties of the glomeruli, the Col18a1(-/-) glomeruli being ~30% softer than the wild-type. Analysis of promoter-specific knockouts (Col18a1(P1/P1) and Col18a1(P2/P2)) indicated that tubular BM loosening is due to a lack of the shortest isoform, whereas the glomerular podocyte effacement was due to a lack of the longer isoforms. We suggest that lack of collagen XVIII may also have disparate effects on kidney function in man, but considering the mild physiological findings in the mutant mice, such effects may manifest themselves only late in life or require other compounding molecular changes.  相似文献   
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The abuse of anabolic androgenic steroids (AASs), such as nandrolone, is not only a problem in the world of sports but is associated with the polydrug use of non-athletes. Among other adverse effects, AAS abuse has been associated with long term or even persistent psychiatric problems. We have previously found that nandrolone decanoate treatment could produce prolonged changes in rats’ brain reward circuits associated to drug dependence. The aim in this study was to evaluate whether AAS-induced neurochemical and behavioral changes are reversible.The increases in extracellular dopamine (DA) and serotonin (5-HT) concentration, as well as stereotyped behavior and locomotor activity (LMA) evoked by cocaine were attenuated by pretreatment with nandrolone. The recovery period, which was needed for the DA system to return back to the basic level, was fairly long compared to the dosing period of the steroid. In the 5-HT system, the time that system needed to return back to the basal level, was even longer than in the DA system. The attenuation was still seen though there were no detectable traces of nandrolone in the blood samples.Given that accumbal outflow of DA and 5-HT, as well as LMA and stereotyped behavior are all related to reward of stimulant drugs, this study suggests that nandrolone decanoate has significant, long-lasting but reversible effects on the rewarding properties of cocaine.  相似文献   
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Nitrogen transformations in the soil, and the resulting changes in carbon and nitrogen compounds in soil percolate water, were studied in two stands of Norway spruce (Picea abies L.). Over the last 30 years the stands were repeatedly limed (total 6000 kg ha–1), fertilized with nitrogen (total about 900 kg ha–1), or both treatments together. Both aerobic incubations of soil samples in the laboratory, and intact soil core incubations in the field showed that in control plots ammonification widely predominated over nitrification. In both experiments nitrogen addition increased the formation of mineral-N. In one experiment separate lime and nitrogen treatments increased nitrification, in the other, only lime and nitrogen addition together had this effect. In one experiment immobilization of nitrogen to soil microbial biomass was lower in soil only treated with nitrogen. Soil percolate water was collected by means of lysimeters placed under the humus layer and 10 cm below in the mineral soil. Total N, NH4-N and NO3-N were measured, and dissolved organic nitrogen was fractioned according to molecular weight. NO3-N concentrations in percolate water, collected under the humus layer, were higher in plots treated with N-fertilizer, especially when lime was also added. The treatments had no effect on the N concentrations in mineral soil. A considerable proportion of nitrogen was leached in organic form.  相似文献   
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Zusammenfassung Ein neuer thermophiler Actinomycet, Streptomyces fragmentosporus wird beschrieben. Kennzeichnend für die Art sind gabelig bis rechtwinklig verzweigte Sporophoren mit kurzen, geraden Ketten aus locker gestellten, stacheligen Fragmentationssporen und die Bildung von Fragmentationssporen im Substratmycel. Neben den Sporophoren werden lange Lufthyphen entwickelt, die teils Sporophoren tragen und gewöhnlich basipetal in Sporen zerfallen. Das Luftmycel ist weiß. Substrat-und Luftsporen sind polymorph. Die Art wächst nur auf wenigen komplexen Nährböden, Pigmente oder Melanin werden nicht gebildet. Streptomyces fragmentosporus ist am nächsten mit der mesophilen Art Streptomyces ramulosus verwandt. Die vergleichende morphologische Untersuchung beider Arten zeigte eine große Übereinstimmung in der Differenzierung des Substrat-und Luftmycels.
Streptomyces fragmentosporus, a new thermophilic actinomycete
Summary The new thermophilic species Streptomyces fragmentosporus is described. The organism is characterized by short, straight, often rectangularly branched aerial sporophores with loosely arranged fragmentation spores, and by the production of fragmentation spores in the substrate mycelium. Beside the sporophores long aerial hyphae are developed which may bear sporophores, and usually fragmentate into spores in basipetal direction. The spores are polymorph and bear small spines.Good growth and production of aerial mycelium was obtained only on manure- and hay-yeast-agar. No pigments or melanin were formed, and no antibiotic activity was observed. The optimum temperature was 50 to 60° C. Streptomyces fragmentosporus is most closely related to the mesophilic Streptomyces ramulosus. It differs from that species mainly by the colour of the aerial mycelium, the absence of pigments, and by the spiny spores which are connected in the chains by ± long parts of hyphal remnants.In a comparative morphological study Streptomyces ramulosus was found to produce abundantly short, ± rectangularly branched sporophores as reported by Shirling and Gottlieb (1968), and occasionally long aerial hyphae bearing sporophores as described by Ettlinger and coworkers (1958). In contrast to the latter authors we observed a production of spores also in these long hyphae like in Streptomyces fragmentosporus.


Die Untersuchung wurde durch eine Sachbeihilfe der Deutschen Forschungsgemeinschaft unterstützt.  相似文献   
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Ecosystems - Climate change and the related increases in evapotranspiration threaten to make northern peatlands drier. The carbon sink function in peatlands is based on the delicate balance between...  相似文献   
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