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161.
The automated determination of glucosamine,galactosamine, muramic acid,and mannosamine in soil and root hydrolysates by HPLC 总被引:2,自引:0,他引:2
Astrid Appuhn Rainer Georg Joergensen Markus Raubuch Edwin Scheller Brigitte Wilke 《植物养料与土壤学杂志》2004,167(1):17-21
Amino sugars make a significant contribution to soil organic N and are mainly of microbial origin. The most important amino sugars in soil are glucosamine, galactosamine, muramic acid, and mannosamine. A method was developed for the simultaneous determination of these four amino sugars by high‐performance reverse‐phase liquid chromatography in standard solutions, soil and root hydrolysates. Pre‐column derivatization with o‐phthaldialdehyde (OPA) was used in an automated sample injector with thermostatic regulation of the reagent at 4 °C. The separation of the four amino sugars was fully satisfactory and was not disturbed by other fluorescent components in the soil and root hydrolysates. 相似文献
162.
Eleonora Deschamps Virginia S. T. Ciminelli Frank Thomas Lange J?rg Matschullat Brigitte Raue Hanka Schmidt 《Journal of Soils and Sediments》2004,4(3):169
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median
concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and
to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil
and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential
effects and how they compare with current screening and threshold values. While surface soil As-val-ues are reproducible at
a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrologicai variances.
Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential
health risk. 相似文献
163.
Eleonora?DeschampsEmail author Virginia?S.?T.?Ciminelli Frank?Thomas?Lange J?rg?Matschullat Brigitte?Raue Hanka?Schmidt 《Journal of Soils and Sediments》2002,2(4):216-222
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median
concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and
to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil
and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential
effects and how they compare with current screening and threshold values. While surface soil As-values are reproducible at
a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrological variances.
Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential
health risk. 相似文献
164.
Beat Schäffer Lisa Eggenschwiler Brigitte Suter Lea Vogt Bernhard Buchter Hans Pfister Rainer Schulin 《植物养料与土壤学杂志》2007,170(5):669-681
Influence of temporary stockpiling on the initial development of restored topsoils Due to increasing construction and open‐cast mining activities on fertile agricultural land, excavation, stockpiling, and restoration of soils have become important issues in soil protection. In this study, we performed a restoration experiment to investigate how the conditions during stockpiling may influence initial soil development and plant growth on a restored site. Four topsoils, which originated from two depths (with uninhibited and inhibited aeration) of a nontrafficked and a trafficked topsoil deposit, were repacked in strips and sown with three meadow‐seed mixtures in strips perpendicular to the soil strips. During stockpiling as well as during the first 2 years after restoration, we assessed the physical and mechanical properties of the topsoils and (after restoration) also plant growth. None of the investigated properties of the topsoils was influenced by the depth in the deposit. In contrast, the coarse porosity and compression index were lower, whereas the bulk density and precompression stress were higher in the trafficked than in the nontrafficked topsoil deposit. However, these differences largely disappeared already in the course of soil restoration. Contrary to our expectations, the plants grew better on the soil of the trafficked topsoil deposit than on the soil of the nontrafficked topsoil deposit in the year of restoration. This might be attributed to the extremely dry and hot summer of that year. In the course of the 2 years following restoration, also the differences in plant growth tended to disappear. The remaining differences in bulk density and plant growth could not be attributed to differences in stockpiling conditions. The results suggest a re‐examination of current soil restoration guidelines. The maximum permitted stockpiling heights for topsoils might be increased in order to reduce the areas required for temporary stockpiling. 相似文献
165.
166.
M. Kirchgessner Brigitte Gedek Susanne Wiehler A. Bott U. Eidelsburger F. X. Roth 《Journal of animal physiology and animal nutrition》1992,68(2):73-81
Insgesamt 48 Kreuzungsferkel (DL × P) wurden nach einem Wachstumsversuch von 42 Tagen geschlachtet und der Inhalt von Duodenum, Jejunum, Ileum, Caecum und Colon auf mögliche Veränderungen der Keimzahlen von Laktobazillen/Bifidobakterien, Eubacteria, Bacteroidaceae, E. coli und Enterokokken untersucht. Als Zulagen wurden dem Futter neben einer Kontrollgruppe 1,25% Ameisensäure oder äquivalent im Säureanionengehalt 1,8% Calciumformiat (Cafo) zugelegt. Diese drei Behandlungen wurden zudem ohne bzw. mit 2% Natriumhydrogencarbonat (Puffer) versehen. Der Puffer sollte die pH-Wert-Absenkung der Ameisensäure wieder ausgleichen. Durch den Zusatz von 1,25% Ameisensäure und 1,8% Cafo wurden im Duodenum und Jejunum die Keimzahlen der Bacteroidaceae und E. coli signifikant gesenkt. Im Jejunum hatte Ameisensäure zudem verminderte Eubacteria-Keimzahlen zur Folge. Der Zusatz von Puffer I führte im Duodenum und Jejunum stets zu höheren Keimzahlen, unabhängig davon, ob er zur Kontrollration, Cafo- oder Ameisensäure-Behandlung zugelegt wurde. Im Ileuminhalt wies die Ameisensäure-Gruppe von allen Spezies die niedrigsten Keimzahlen auf. Die E. coli-Keime waren auch in der Cafo- sowie der gepufferten Ameisensäure-Gruppe nominell reduziert. Im Caecum und Colon konnten gegenüber der Kontrollgruppe keine signifikanten Veränderungen in den Keimzahlen festgestellt werden. Allgemein lagen jedoch die Laktobazillen/Bifidobakterien, Eubacteria, Bacteroidaceae und E. coli-Keime in der Ameisensäure- und Cafo-Gruppe jeweils in geringeren Keimzahlen vor. 相似文献
167.
Brigitte Dorn Hans-Rudolf Forrer Stéphanie Schürch Susanne Vogelgsang 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):51-61
The Fusarium species complex of maize kernels and stem pieces as well as mycotoxin contamination of commercial grain maize hybrids for
animal feed were evaluated in Switzerland. Throughout 2 years, natural Fusarium infection varied significantly between the years and the locations and it ranged from 0.4% to 49.7% for kernels and from
24.2% to 83.8% for stem pieces. Using the agar plate method, 16 different Fusarium species were isolated from kernels and 15 from stem pieces. The Fusarium species composition, prevalence and impact differed between the north and the south and between kernel and stem piece samples.
The dominant species on kernels in the north were F. verticillioides (32.9%), F. graminearum (31.3%), F. proliferatum (7.3%) and F. crookwellense (7.1%), in the south F. verticillioides (57.1%), F. subglutinans (24.6%), F. proliferatum (14.8%) and F. graminearum (1.5%) and on stem pieces F. equiseti (36.0%), F. verticillioides (20.1%), F. graminearum (9.5%), F. crookwellense (6.2%) and F. subglutinans (6.2%). In the south, fumonisin concentration of most hybrids exceeded guidance values for animal feed. Other Fusarium species isolated were F. avenaceum, F. culmorum, F. oxysporum, F. poae, F. sambucinum, F. semitectum, F. sporotrichioides, F. solani, F. tricinctum and F. venenatum. Maize hybrids varied in their susceptibility to Fusarium infection. Because of the high diversity of Fusarium species encountered in Switzerland representing a high toxigenic potential, we propose to screen maize hybrids for resistance
against various Fusarium species and examine maize produce for several mycotoxins in order to ensure feed safety. 相似文献
168.
Casrouge A Zhang SY Eidenschenk C Jouanguy E Puel A Yang K Alcais A Picard C Mahfoufi N Nicolas N Lorenzo L Plancoulaine S Sénéchal B Geissmann F Tabeta K Hoebe K Du X Miller RL Héron B Mignot C de Villemeur TB Lebon P Dulac O Rozenberg F Beutler B Tardieu M Abel L Casanova JL 《Science (New York, N.Y.)》2006,314(5797):308-312
Herpes simplex virus-1 (HSV-1) encephalitis (HSE) is the most common form of sporadic viral encephalitis in western countries. Its pathogenesis remains unclear, as it affects otherwise healthy patients and only a small minority of HSV-1-infected individuals. Here, we elucidate a genetic etiology for HSE in two children with autosomal recessive deficiency in the intracellular protein UNC-93B, resulting in impaired cellular interferon-alpha/beta and -lambda antiviral responses. HSE can result from a single-gene immunodeficiency that does not compromise immunity to most pathogens, unlike most known primary immunodeficiencies. Other severe infectious diseases may also reflect monogenic disorders of immunity. 相似文献
169.
170.
Thierry Koumbi-Mounanga Daniela Tudor Brigitte Leblon Kevin Groves Paul A. Cooper Tony Ung 《Wood material science & engineering》2018,13(4):204-221
A combination of statistical techniques of analyses were used to evaluate the potential of International Commission on Illumination (CIE) lightness (L*), redness (a*) and yellowness (b*) colour space system and near-infrared spectroscopy (NIRS) to assess surface changes in relation with progressive decay of beech (Fagus grandifolia Ehrh.) by wood-inhabiting lignicolous fungi Inonotus hispidus, Trametes versicolor and Xylaria polymorpha. pH effects based modelling predictions of beech earlywood and latewood tissues were also included. Multivariate analysis techniques included response surface optimization, sample-specific standard error of prediction (SEP) method and projection to latent structures partial least squares (PLS) regression. Strong statistical relationships were derived for pH predictions with R2 values ranged: from 0.77 to 0.84 for I. hispidus; from 0.77 to 0.84 for T. versicolor and from 0.83 to 0.91 for X. polymorpha. R2 values for CIE-based L*a*b* colour space measurements ranged: from 0.43 to 0.69 (L*), 0.66 to 0.76 (a*), 0.42 to 0.53 (b*) for I. hispidus; from 0.59 to 0.69 (L*), 0.69 to 0.79 (a*), 0.64 to 0.79 (b*) for T. versicolor; and from 0.51 to 0.75 (L*), 0.89 to 0.94 (a*), 0.85 to 0.89 (b*) for X. polymorpha. Multivariate technical analysis (response surface analysis, sample-specific SEP, PLS regression) of CIE L*a*b* system and NIRS results should be able to characterize pH effects and surface changes of wood spalted by lignicolous fungi as a quick and reliable non-destructive method relevant to wood-spalting concerns and the forest products industry. 相似文献