Antibody titer against bovine viral diarrhea virus (BVDV) in bulk milk samples from Bavaria     

Meier N  Meier B  Banzhaf K  Wittkowski G  Schmitt D  Truyen U 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(5-6):240-243

A total of 5204 bulk milk samples were tested for antibodies against bovine viral diarrhea virus (BVDV) classified according to the scheme after Alenius. Forty-five percent of the samples from 2002 were classified as class 0 and class 1, 55% as class 2 and 3. 6420 bulk milk samples from 1997 were classified in an independent study in 65.6% class 0 and 1 and 34.4% in class 2 and 3. In class 0 and class 1 farms only very rarely persistent viremic animals have been found, whereas in class 2 and 3 their presence is highly likely. Our studies with non-selected sera defined the serological screening of bulk milk samples as a promising tool for a possible BVDV eradication program in Bavaria.  相似文献   

Long-term sea-level fluctuations driven by ocean basin dynamics     

Müller RD  Sdrolias M  Gaina C  Steinberger B  Heine C 《Science (New York, N.Y.)》2008,319(5868):1357-1362

Earth's long-term sea-level history is characterized by widespread continental flooding in the Cretaceous period (approximately 145 to 65 million years ago), followed by gradual regression of inland seas. However, published estimates of the Late Cretaceous sea-level high differ by half an order of magnitude, from approximately 40 to approximately 250 meters above the present level. The low estimate is based on the stratigraphy of the New Jersey margin. By assimilating marine geophysical data into reconstructions of ancient ocean basins, we model a Late Cretaceous sea level that is 170 (85 to 270) meters higher than it is today. We use a mantle convection model to suggest that New Jersey subsided by 105 to 180 meters in the past 70 million years because of North America's westward passage over the subducted Farallon plate. This mechanism reconciles New Jersey margin-based sea-level estimates with ocean basin reconstructions.  相似文献   

Bioassays for the ecotoxicological and genotoxicological assessment of contaminated soils (Results of a round-robin test)     

Kerstin?Hund-RinkeEmail author  Werner?Koerdel  Dieter?Hennecke  Rudolf?Achazi  Dietmar?Warnecke  Berndt-Michael?Wilke  Birgit?Winkel  Stefanie?Heiden 《Journal of Soils and Sediments》2002,2(2):83-90

For the assessment of contaminated or remediated soils, aside from chemical analyses, ecotoxicological tests are performed which focus on the retention function of soils (determined by tests with aqueous soil extracts) and on the habitat function (determined by tests with soil). Whereas numerous tests exist as standardized guidelines for identifying the effect of chemicals, this is not the case for the assessment of soil quality. A round-robin test was performed to monitor the comparability of the results from ecotoxicological test methods on soils and to facilitate the standardization of corresponding test methods. Four contaminated soils were tested using a total number of fifteen test systems, including ecotoxicological and genotoxicological tests with soil extracts and soil. In the second part of this publication series, the results obtained from the tests with soil microorganisms and soil fauna are presented.  相似文献   

Extensive diversity of Ig-superfamily proteins in the immune system of insects   总被引：1，自引：0，他引：1  

Watson FL  Püttmann-Holgado R  Thomas F  Lamar DL  Hughes M  Kondo M  Rebel VI  Schmucker D 《Science (New York, N.Y.)》2005,309(5742):1874-1878

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Contribution of organic amendments to soil organic matter detected by thermogravimetry          下载免费PDF全文

David Tokarski  Jiří Kučerík  Karsten Kalbitz  Michael Scott Demyan  Ines Merbach  Dietmar Barkusky  Joerg Ruehlmann  Christian Siewert 《植物养料与土壤学杂志》2018,181(5):664-674

Sustainable soil management requires reliable and accurate monitoring of changes in soil organic matter (SOM). However, despite the development of improved analytical techniques during the last decades, there are still limits in the detection of small changes in soil organic carbon content and SOM composition. This study focused on the detection of such changes under laboratory conditions by adding different organic amendments to soils. The model experiments consisted of artificially mixing soil samples from non‐fertilized plots of three German long‐term agricultural experiments in Bad Lauchstädt (silty loam), Grossbeeren (silty sand), and Müncheberg (loamy sand) with straw, farmyard manure, sheep faeces, and charcoal in quantities from 3 to 180 t ha^?1 each. In these mixtures we determined the organic carbon contents by elemental analysis and by thermal mass losses (TML) determined by thermogravimetry. The results confirmed the higher reliability of elemental analysis compared to TML for organic carbon content determination. The sensitivity of both methods was not sufficient to detect the changes in organic carbon content caused by small quantities of organic amendments (3 t ha^?1 or 0.1–0.4 g C kg^?1 soil). In the case of elemental analysis, the detectability of changes in carbon content increased with quantities of added amendments, but the method could not distinguish different types of organic amendments. On the contrary, the based on analysis of degradation temperatures, the TML allowed this discrimination together with their quantitative analysis. For example, added charcoal was not visible in TML from 320 to 330°C, which is used for carbon content determination. However, increasing quantities of charcoal were reflected in a higher TML around 520°C. Furthermore, differences between measured (with TML_110–550) and predicted mass loss on ignition using both organic carbon (with TML₃₃₀) and clay contents (with TML₁₄₀) were confirmed as a suitable indicator for detection of organic amendments in different types of soils. We conclude that thermogravimetry enables the sensitive detection of organic fertilizers and organic amendments in soils under arable land use.  相似文献   

Leaching of PCE-based Superplasticiser from Microfine Cement: a Chemical and Ecotoxicological Point of View     

Veronika Märkl  Stephan Pflugmacher  Dietmar A. Stephan 《Water, air, and soil pollution》2017,228(6):217

The construction materials industry faces major challenges since 2013 when the European Construction Products Regulation was implemented, especially in the sector of environmentally friendly construction products. This study determined concentrations of leachable inorganic and organic compounds from microfine cement paste with and without superplasticiser addition. Furthermore, the leached superplasticiser amounts were detected via LC-MS. The multi-method approach was supplemented by ecotoxicological assays. Phytotoxicity was tested with white mustard (Sinapis alba) and cress (Lepidium sativum). The mutagenic and genotoxic potential of the leachates was tested with the Ames fluctuation assay and the umuC assay. As leaching protocol, the European horizontal dynamic surface leaching test was used. The cement paste samples with superplasticiser followed the wash-off effect with a total organic carbon release up to 43 mmol/m², whereas the release of samples without superplasticiser was driven by diffusion. The ecotoxicological assays showed a clear time depending behaviour. No cytotoxicity and mutagenicity could be observed; anyhow some leachates show minor genotoxic potential. In all tests, a clear difference between the samples with and without superplasticiser could be detected.This study clearly demonstrates the importance of further studies in the field of leaching of construction products.  相似文献