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101.

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More European heritage awards  相似文献   
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Absorption is one of the most widely used techniques for treating odourous waste gases. An improvement of the effectiveness of gas scrubbers can be achieved by using adapted washing liquids. A screening test is proposed as a low cost tool for testing washing liquids on industrial waste gases. The odour index is used to identify the main cause of the specific smell and to simplify the analysis of absorptive performances of washing liquids. The method is verified by experiments at a chocolate factory and a fat and oil refinery.  相似文献   
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Disturbance to ecosystems in parks and protected areas from nature-based tourism and recreation is increasing in scale and severity, as are the impacts of climate change—but there is limited research examining the degree to which these anthropogenic disturbances interact. In this perspective paper, we draw on the available literature to expose complex recreation and climate interactions that may alter ecosystems of high conservation value such that important species and processes no longer persist. Our emphasis is on ecosystems in high demand for tourism and recreation that also are increasingly experiencing stress from climate change. We discuss the importance of developing predictive models of direct and indirect effects, including threshold and legacy effects at different levels of biological organization. We present a conceptual model of these interactions to initiate a dialog among researchers and managers so that new research approaches and managerial frameworks are advanced to address this emerging issue.  相似文献   
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Abnormally developing embryos (ADEs) of the common pill millipede Glomeris marginata have been investigated by means of nuclear staining and mRNA in situ hybridization. It showed that all ADEs represent cases of Duplicitas posterior, which means that the posterior body pole is duplicated. The severity of the duplication ranges from duplicated posterior trunk segments in one specimen to an almost completely duplicated specimen that only shares the very anterior head region. Remarkably, none of the encountered ADEs represents a case of Duplicitas anterior (duplicated anterior pole) or a case of Duplicitas cruciata (cruciate duplication with two anterior and two posterior poles). This observation is discussed in the light of earlier reports on G. marginata ADEs that claim to have found these abnormalities. The lack of any other axial abnormality aside from D. posterior implies that early axis determination in G. marginata, and possibly myriapods in general, underlies the developmental mechanisms that prevent the formation of any other type of axial duplication. It is proposed that the formation of D. posterior-type embryos could be caused by the formation of two instead of only one posterior cumulus early during development.  相似文献   
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Mycotoxins are a heterogeneous group of secondary fungal metabolites. Their formation in food and feedstuffs is influenced by many factors, including humidity, temperature, pH, oxygen concentration, type of substrate or presence of competitive microflora. The Food and Agriculture Organisation of the United Nations estimated in 1985 that approximately 25% of the world’s grain supply is contaminated with mycotoxins. There are more than 300 known mycotoxins; however, due to their occurrence and concentrations in food, and their toxic potential, only few of these are relevant with regard to consumer protection. These include the aflatoxins, ochratoxins and trichothecenes like deoxynivalenol, zearalenone and fumonisins. In Germany, only aflatoxins in food and feedstuffs are subjected to legal regulations. Beside the negative effects of mycotoxins on health and performance of farm animals, it is of importance to consider to what extent mycotoxins might be carried over into edible tissues like meat, milk and eggs when fed to farm animals. The present review shows that the carry over of mycotoxins into edible tissues is relatively low and is dependent on the specific mycotoxin and animal species. For example, due to the microbial decomposition of mycotoxins in the rumen, the carry over of mycotoxins into edible tissues of ruminants is considerably lower compared to monogastric species (pigs, chickens). Furthermore, after a short withdrawal period of 4 to 14 days combined with the feeding of non-contaminated diets, most of the mycotoxins, aside from ochratoxin A, are no longer detectable in any edible tissue. Ochratoxin A has a high binding affinity to specific blood proteins and is reabsorbed in the kidney; these mechanisms delay its elimination and increase the withdrawal period to at least 4 weeks. However, aside from the concentration of these substances in food, the daily intake of contaminated food is important for the risk analysis of mycotoxins to humans. In a recent study, it has been shown that more than 50% of the daily intake of ochratoxin A is derived from cereals and cereal products, and 30% from red wine, coffee and beer. Mear products from pigs and chickens only account for 4% of the total intake, while products from ruminants are considered to be negligible. These results indicate that mycotoxin-contaminated edible tissue, as compared to plant products, only plays a minor role with respect to consumer protection.  相似文献   
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Ohne Zusammenfassung Dr. rer. nat. Henner Hollert: • Leitung lokales Organisationskomittee SETAC-GLB 2003 • Studium der Biologie und Geographie an der Universit?t Heidelberg von 1990 bis 1997. Februar 1997: Diplom in Biologie, Oktober 1997: Erstes Staatsexamen für das h?here Lehramt in Biologie/Geographie • Von November 1997 bis April 2001: Promotion über die Entwicklung eines kombinierten Untersuchungssystems für die Bewertung der ?kotoxikologischen Belastung von Flie?gew?ssersedimenten und-schwebstoffen • Forschungsaufenthalte 1999 und 2000 an den Universit?ten Uppsala und ?rebro (Schweden) zur Untersuchung der Dioxin-?hnlichen Wirksamkeit von Sedimenten in embryonaler Hühnerleberkultur • In der Lehre seit 2000 als Wissenschaftlicher Angestellter am Zoologischen Institut (Abt. Morphologie/?kologie) mit den Schwerpunkten ?kotoxikologie, ?kologie und Zoologie t?tig • Leitung der Arbeitsgruppe Sediment- und Bodentoxikologie • Forschungsschwerpunkte: Sediment- und Bodentoxikologie, Hochwasseruntersuchunge, Bioassay-dirigierte Fraktionierungstechniken, Statistische Bewertungsmethoden, Integrierte Sedimentuntersuchungen (Kombination aus Makrozoobenthosanalysen, in-vitro-Biotests und chemischer Analytik) • Vizepr?sident der deutschsprachigen Sektion der SETAC-GLB (Society of Environmental Toxicology and Chemistry) • Organisationskomitee der europ?ischen Jahrestagung der SETAC und des Club of Rome in Hamburg-Harburg 2003 • Seit dem 11. Juni 2003 geh?rt Henner Hollert dem UWSF-Herausgebergremium an  相似文献   
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The formation of aromatic amines was investigated using a summarized test (NEDA-test) during the composting of 2,4,6-trinitrotoluene (TNT) contaminated soil. In this test, the aromatic amines were diazolated and then coupled to N-1-Naphthyl-ethylenediamine-dihydrochloride (NEDA) to yield an azo dye which can be monitored photometrically. The test was calibrated for known TNT-metabolites with an active amine-group. Liquid samples from composting- and liquid-culture-experiments were analyzed by HPLC for these known metabolites. Moreover, the samples were monitored by the NEDA-test and the expected extinction of the TNT-metabolites found with amine function were extrapolated with the help of calibration curves. It was shown that substantial differences are obvious between the monitored and extrapolated values. After separation into polar and non-polar aromatic amines, it became clear that these differences are made by the polar aromatic amines. Polar aromatic amines, which are not detectable by presently available analytical tests, were generated during the composting of TNT-contaminated soils. Contaminated stagnant water, which was generated during anaerobization of a compost prephase, was treated aerobically for 70 days in a biofermenter. During this treatment TNT and its known metabolites were eliminated almost entirely. Simultaneously, the toxicity in the Lumis Tox-test decreased drastically. In striking contrast, the sum of aromatic amines decreased only to a minor extent. Moreover, the percentage of polar compounds from total amount of aromatic amines increased drastically from 48% to more than 95%. At present, the chemical identification of these polar compounds is still missing and is the object for further research.  相似文献   
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