Protecting the Commons: the use of Subtidal Ecosystem Engineers in Marine Management          下载免费PDF全文

Ulrike Braeckman  Marijn Rabaut  Jan Vanaverbeke  Steven Degraer  Magda Vincx 《水产资源保护:海洋与淡水生态系统》2014,24(2):275-286

Extraintestinal pathogenic Escherichia coli in poultry meat products on the Finnish retail market     

Ulrike Lyhs  Ilona Ikonen  Tarja Pohjanvirta  Kaisa Raninen  P?ivikki Perko-M?kel?  Sinikka Pelkonen 《Acta veterinaria Scandinavica》2012,54(1):64

Background

Extraintestinal pathogenic Escherichia coli bacteria (ExPEC) exist as commensals in the human intestines and can infect extraintestinal sites and cause septicemia. The transfer of ExPEC from poultry to humans and the role of poultry meat as a source of ExPEC in human disease have been discussed previously. The aim of the present study was to provide insight into the properties of ExPEC in poultry meat products on the Finnish retail market with special attention to their prevalence, virulence and phylogenetic profiles. Furthermore, the isolates were screened for possible ESBL producers and their resistance to nalidixic acid and ciprofloxacin was tested.

Methods

The presence of ExPEC in 219 marinated and non-marinated raw poultry meat products from retail shops has been analyzed. One E. coli strain per product was analyzed further for phylogenetic groups and possession of ten virulence genes associated with ExPEC bacteria (kpsMT K1, ibeA, astA, iss, irp2, papC, iucD, tsh, vat and cva/cv) using PCR methods. The E. coli strains were also screened phenotypically for the production of extended-spectrum β-lactamase (ESBL) and the susceptibility of 48 potential ExPEC isolates for nalidixic acid and ciprofloxacin was tested.

Results

E. coli was isolated from 207 (94.5%) of 219 poultry meat products. The most common phylogenetic groups were D (50.7%), A (37.7%), and B2 (7.7%). Based on virulence factor gene PCR, 23.2% of the strains were classified as ExPEC. Two ExPEC strains (1%) belonged to [O1] B2 svg+ (specific for virulent subgroup) group, which has been implicated in multiple forms of ExPEC disease. None of the ExPEC strains was resistant to ciprofloxacin or cephalosporins. One isolate (2.1%) showed resistance to nalidixic acid.

Conclusions

Potential ExPEC bacteria were found in 22% of marinated and non-marinated poultry meat products on the Finnish retail market and 0.9% were contaminated with E. coli [O1] B2 svg+ group. Marinades did not have an effect on the survival of ExPEC as strains from marinated and non-marinated meat products were equally often classified as ExPEC. Poultry meat products on the Finnish retail market may have zoonotic potential.  相似文献   

No evidence of superclones in leaf-feeding forms of austrian grape phylloxera (Daktulosphaira vitifoliae)     

Forneck  Astrid  Anhalt  Ulrike C. M.  Mammerler  Roswitha  Griesser  Michaela 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):441-448

European Journal of Plant Pathology - The genetic structure of ten grape phylloxera populations, sampled in summer of 2006 and 2007 from four distinct viticultural areas in Austria, Daktulosphaira...  相似文献   

Monitoring of root‐zone water content in the laboratory by 2D geoelectrical tomography     

Ulrike Werban  Said Attia al Hagrey  Wolfgang Rabbel 《植物养料与土壤学杂志》2008,171(6):927-935

Root water uptake is one of the essential processes within the soil–plant–atmosphere continuum. We present a method for monitoring soil‐water redistributions due to water uptake by roots. Our aim is to image and monitor diurnal soil‐water redistribution during a small‐scale (centimeter‐to‐decimeter range) indoor experiment and to correlate water content determined by applied geoelectrical time‐lapse imaging techniques with values from single‐point time domain reflectometry (TDR) measurements. This includes establishing pedophysical relationships within the root zone and deriving the water‐content distribution from the electrical‐resistivity model. Using DC geoelectrics of high resolution (970 data points for 220 cm²), we monitored significant spatial heterogeneity of soil moisture with time, whereas no irrigation was applied. Thus, we imaged the high heterogeneity of fluid movements within the soil. We found diurnal variations with high spatial variability of soil water content during the morning and afternoon hours. The water content continuously increased from dawn to noon, whereas the increase started in the near‐surface zone from 1 cm to 3 cm above the main root zone. Between 8:00 a.m. and 10:00 a.m., water content decreases along most of the sections. Water content irregularly decreases and increases during the afternoon. During night time, we observed nearly no changes in soil water content due to the absence of transpiration and subsequently soil‐water redistribution. Most of these diurnal variations in soil water content lie within the intensive root zone, as measurements showed on soil samples excavated from these areas after the experiment. Furthermore, we quantified water content derived from geoelectrical tomography of the monitored area before and after an irrigation event using a geophysical pedotransfer function of Archie, established specifically for the used lupine and the applied physico‐chemical boundary conditions of the experiment. The resulting average water content from 2D geoelectrical tomography agreed well with the values determined by the TDR measurements.  相似文献   

Red fluorescence in reef fish: A novel signalling mechanism?     

Nico K Michiels  Nils Anthes  Nathan S Hart  Jürgen Herler  Alfred J Meixner  Frank Schleifenbaum  Gregor Schulte  Ulrike E Siebeck  Dennis Sprenger  Matthias F Wucherer 《BMC ecology》2008,8(1):16

Background  

At depths below 10 m, reefs are dominated by blue-green light because seawater selectively absorbs the longer, 'red' wavelengths beyond 600 nm from the downwelling sunlight. Consequently, the visual pigments of many reef fish are matched to shorter wavelengths, which are transmitted better by water. Combining the typically poor long-wavelength sensitivity of fish eyes with the presumed lack of ambient red light, red light is currently considered irrelevant for reef fish. However, previous studies ignore the fact that several marine organisms, including deep sea fish, produce their own red luminescence and are capable of seeing it.  相似文献   

Fish Biomechanics. Volume 23 in the Series 'Fish Physiology'     

Ulrike Müller 《Fish and Fisheries》2007,8(1):73-74

  相似文献   

An integrative approach for analysing landscape dynamics in diverse cultivated and natural mountain areas   总被引：3，自引：1，他引：2  

Erich Tasser  Flavio V. Ruffini  Ulrike Tappeiner 《Landscape Ecology》2009,24(5):611-628

Our landscape can be regarded as a development process that is affected and subsequently shaped by a series of different environmental and human-induced factors. However, to date, concrete data about the impact of each of these factors are still missing. One key reason for this is that methods of acquisition and evaluation of these factors inherently have differences, thereby preventing meaningful comparative analyses. This study presents an integrative methodical approach that bridges many of these gaps. Our approach also has the advantages of being generally applicable while delivering easily interpretable results that also allow comparisons between diverse geographical regions. The indicators used enable all major features of landscape change, e.g. changes in land use, landscape structuring, habitat settings, and urban sprawl, to be accurately monitored and provide high-quality realistic results that were validated in our study site, South Tyrol (North Italy). Indicators were selected for both their further subdivision, e.g. monocrops and different features of mixed crops, and their easy to ascertain hierarchically structured feature classification, e.g. land cover. Furthermore, our use of ecoregions enables better comparison of aspects of landscape development for geographical regions having diverse socio-economic and ecological conditions. Our methodical approach can be used as a basis not only for creating landscape change scenarios, but also for determining the environmental and human-induced factors involved and being able to list them in order of importance. Further the detected striking difference between the mapped land-use data and the official census data suggests a validation of the methodical approach in context of the national agriculture census.  相似文献   

Bodenmykoflora in unterschiedlichen Bewirtschaftungssystemen des Weizens mit besonderer Berücksichtigung der Fusarium‐Akten     

Ulrike Damm 《Archives of Agronomy and Soil Science》2013,59(6):509-521

In einem Feldversuch wurden in drei Jahren die Auswirkungen unterschiedlicher Bewirtschaftungssysteme des Weizens auf die Bodenmykoflora untersucht. Dabei wurde ein Bewirtschaftungssystem mit Vorfrucht Grünbrache, konservierender Bodenbearbeitung mit Grubber und unterlassener Stickstoffdüngung (Variante E) einem System mit Vorfrucht Silomais, konventioneller Bodenbearbeitung mit Pflug und mineralischer Stickstoffdüngung (Variante I) gegenübergestellt. Die Besiedlungsdichte und das Spektrum der Bodenpilze wurden durch Auslegen von Bodenpartikeln auf Nährboden untersucht. Die Artbestimmung der Gattung Fusarium stand dabei im Vordergrund.

Die Bodenproben der Variante E zeigten quantitativ und qualitativ eine höhere Pilzbesiedlung als die Proben der Variante I. Die Gattung Fusarium war zu jedem Probenahmetermin im Boden der Variante E deutlich häufiger, wobei sowohl saprophytische Arten (z. B. F. tabacinum) als auch die pathogene Art F. eulmorum zu nennen sind. Neben Fusarium zeigten auch Gattungen wie Alternaria, Cladosporium und Mucor die zum Teil antagonistische Fähigkeiten gegenüber F. eulmorum besitzen, höhere Abundanzen in den Bodenproben der Variante E.  相似文献   

Prevalence and antimicrobial susceptibility of Salmonella spp. in small Indian mongooses (Herpestes auropunctatus) in Grenada,West Indies     

Steven Miller  Victor Amadi  Diana Stone  Roger Johnson  Harry Hariharan  Ulrike Zieger 《Comparative immunology, microbiology and infectious diseases》2014

Intestinal samples from 156 small Indian mongooses (Herpestes auropunctatus) collected island-wide in Grenada from April 2011 to March 2013 were examined for the presence of Salmonella enterica spp. Nineteen (12%) mongooses were culture-positive for S. enterica spp. of which five serotypes were identified. Salmonella javiana and S. Montevideo were the most commonly isolated serotypes. The other serotypes isolated were S. Rubislaw, S. Panama and S. Arechavaleta. All isolates were susceptible to amoxicillin–clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, imipenem and trimethoprim–sulfamethoxazole. One isolate (S. Montevideo) showed resistance to tetracycline and intermediate resistance to streptomycin. The five isolated Salmonella serotypes are potential human pathogens suggesting that the mongoose may play a role in the epidemiology of human salmonellosis in Grenada.  相似文献   

A combined hydraulic and toxicological approach to assess re-suspended sediments during simulated flood events. Part I–multiple biomarkers in rainbow trout     

Markus Brinkmann  Sebastian Hudjetz  Catrina Cofalla  Sebastian Roger  Ulrike Kammann  John P. Giesy  Markus Hecker  Steve Wiseman  Xiaowei Zhang  Jan Wölz  Holger Schüttrumpf  Henner Hollert 《Journal of Soils and Sediments》2010,10(7):1347-1361

Purpose

One of the central issues related to global changes in weather is the increasing occurrence of flood events that can result in the re-suspension of contaminated sediments in rivers. Here, we report on a proof-of-concept study combining hydraulic engineering and ecotoxicology in a new interdisciplinary approach to assess the toxicity of re-suspended polluted sediments after a simulated flood event.

Materials and methods

Rainbow trout (Oncorhynchus mykiss) were exposed for 5 days under simulated flood conditions in an annular flume with artificial sediments that were spiked with a mixture of polycyclic aromatic hydrocarbons (PAH) at environmentally relevant concentrations. Specifically, the objective of this study was to bridge the gap between the physical re-suspension of pollutants and resulting toxicological impacts on aquatic organisms. A suite of different molecular, biochemical and histological markers was used to test the hypothesis that re-suspension of sediments can lead to re-mobilization of PAHs and subsequently to effects on aquatic organisms.

Results and discussion

The micronucleus frequency was significantly 4.3-fold elevated after exposure. There was no significant indication of Aryl hydrocarbon receptor signaling (no EROD induction or increased CYP1A protein content, only slight induction of CYP1A gene expression). Biliary metabolite concentration was the most sensitive marker of PAH exposure. Results for other biomarkers (glutathione-S-transferase, catalase and lipid peroxidation) were inconclusive.

Conclusions

In combination with chemical analyses of suspended matter, the presented approach will be used to improve understanding of the re-mobilization of pollutants from sediments in support of environmental risk assessment.  相似文献