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101.
Theodoridis D Schwarz S Kietzmann M Strutzberg-Minder K 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(1-2):50-60
In Germany, the application of antimicrobial agents represents the method of choice to control infections of food-producing animals by bacteria of the genus Leptospira. However, only few data are available on the susceptibility of Leptospira spp. against antimicrobial agents and the in vivo efficacy of antimicrobial agents. Based on a modified broth microdilution method, a standardised in-vitro susceptibility testing system for Leptospira spp. was established which also included quality control aspects. Considering the minimum inhibitory concentrations determined in this study in-vivo efficacy is expected for the following classes of antimicrobial agents: penicillins, cephalosporins, macrolides, lincosamides, fluoroquinolones, phenicols, and in part also for aminoglycosides and tetracyclines. Clinical aspects and bioavailability of the drugs in the target tissues have to be taken into account. Penicillins and aminoglycosides as commonly used inhibitory supplements in semen extender seem to be effective against leptospires. 相似文献
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Detlef Deumlich Jürgen Thiere Manfred Altermann 《Archives of Agronomy and Soil Science》2013,59(6):767-784
Spatial assessment of soil properties needs conversion of point data to an area-oriented model. Methods are required that create a reproducible map. The development of a map is shown by the example of cation exchange capacity. Twenty sorption types are formed and derived from the vertical sequence of values for substrate types and are aggregated to six main types. A qualitative assessment of the main CEC sorption types is carried out with comparative ranking. The association of different substrate types on an areal soil pattern requires the identification of sorption association types. These are shown by the areal share of the main sorption types for the substrate types involved in each case. For interpreting the site parameters from the MMK (Mittelmaßstäbige Landwirtschaftliche Standortkartierung), the procedure is presented in detail. An example of the results is shown with CEC maps. Tables complement the visualization for different areas, defined by administrative or natural landscape boundaries. The application of this method for relative evaluation of CEC is demonstrated using KA5-rules. The CEC characterization of agricultural areas can be reproduced on the basis of the mapping units of soil maps with different scales (BÜK 200). The areal-specific labeling of CEC constitutes soil-related decision guideline. 相似文献
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Pontamine fast scarlet 4B: a new fluorescent dye for visualising cell wall organisation in radiata pine tracheids 总被引:1,自引:0,他引:1
Jimmy Thomas Manfred Ingerfeld Hema Nair Shakti Singh Chauhan David A. Collings 《Wood Science and Technology》2013,47(1):59-75
Using confocal microscopy, tracheid wall organisation was investigated with pontamine fast scarlet 4B (P4B), a cellulose-specific stain that fluoresced red following green excitation. P4B fluorescence was present throughout unlignified walls (cambium, ray cells, resin canals and parenchyma cells) and in two concentric bands around opposite and compression wood tracheids. Scanning electron micrographs demonstrated these bands as the S1 and S3 layers of normal wood, and the S1 and inner S2 layers of compression wood. Fluorescence was also strongly dependent on the polarisation of the excitation light, a phenomenon referred to as bifluorescence. Compared to two other cell wall stains, Congo red and calcofluor white, P4B showed a higher specificity for the S1 and S3 layers and increased bifluorescence. These results suggest that P4B is an ideal tool with which to investigate the orientation of cellulose microfibrils in the S1 and S3 layers of the tracheid wall. 相似文献
107.
Richard Simon Mwakapuja Zachariah Ephraim Makondo Joseph Malakalinga Ward Bryssinckx Robinson Hammerthon Mdegela Irmgard Moser Rudovick Reuben Kazwala Manfred Tanner 《Tropical animal health and production》2013,45(5):1223-1230
Bovine tuberculosis (BTB) is an important neglected zoonosis that affects livestock, wildlife and human. A study to determine prevalence and geospatial clusters for BTB was conducted from June 2010 to March 2012 at livestock–wildlife interface areas (LWIA). A total of 1,288 cattle located in vicinity of Mikumi-Selous ecosystem Tanzania were tested. Single Intradermal Comparative Tuberculin Test and spatial scan statistic analysis were applied to establish the status of the disease and identify significant spatial BTB clusters. Overall individual prevalence was 3.7 % (n?=?1,288) (95 % CI?=?2.8–4.9) and 7.8 % (95 % CI?=?6.4–9.4) with cut-off of >4 and >2 mm, respectively. Villages with at least one reactor were 55.8 % (n?=?43). Reactivity was significantly higher in Mvomero and Kilosa districts compared with Kilombero and Ulanga districts (χ 2?=?15.9; P?<?0.001). Significant spatial BTB clusters were revealed at 11 villages. BTB clustering was significant in Kilosa and Mvomero districts compared with Kilombero and Ulanga districts. There was overlap and aggregation of BTB clusters covering south and south-east of Kilosa district bordering Mikumi National Park (MNP) and Mvomero. Generally, clustering occurred around major rivers. The current study provides useful information on the dynamics and epidemiological status of BTB around the wildlife–livestock–human interface, it reveals that the wildlife are at risk of BTB from infected livestock. The study revealed hotspots for BTB that can be applied to guide implementation of participatory intervention at LWIA and control strategies in marginalised pastoralist communities. This study calls for similar studies in other Tanzania’s LWIA for efficient intervention of BTB countrywide. 相似文献
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Marc Breulmann Elke Schulz Manfred van Afferden Roland A. Müller Christoph Fühner 《Archives of Agronomy and Soil Science》2018,64(6):860-872
Large amounts of labile compounds are adsorbed to the surface of chars produced by hydrothermal carbonization (HTC). The aim of this study was to characterize the core and adsorbed fractions of hydrochars and to gain knowledge about the possibility to remove phytotoxic compounds by washings with water. Chars were produced by HTC of sewage sludge at different temperatures (180 – 200 °C) and over different periods of time (4 – 8 h). For comparison one pyrolysis char produced by thermocatalytic low temperature conversion (LTC) at 400 °C for 1 h was included in the study. The chars and their feedstocks were treated varying the duration (1 x 15, 1 × 30 and 1 × 60 min) and number (2 x 60 and 3 × 60 min) of washings. Physicochemical properties, including the molecular structure of the test materials, and their effects on germination and plant growth were analysed. Element concentrations and phytotoxic effects were reduced and the number of washings had a stronger effect than their length of time. Intensive washings with water reduced the hydrochars’ portion of biodegradable compounds significantly. However, also plant available nutrients were lost by washing with water, decreasing the value of hydrochars as a soil amendment. 相似文献
110.
Joachim H. Spangenberg K. L. Heong Anika Klotzbücher Thimo Klotzbücher Quynh Anh Nguyen Vera Tekken Dao Thanh Truong Manfred Türke Josef Settele 《Paddy and Water Environment》2018,16(2):321-337
The transdisciplinary research project LEGATO analysed the combined generation of provisioning, regulating and cultural ecosystem services in wet rice agriculture in South-East Asia and applied ecological engineering to future-proof it against global change and environmental pollution challenges. Due to its transdisciplinary character and the sheer size, a systematic stakeholder involvement was inevitable. Starting with stakeholder identification by snowballing from a limited number of contacts, we derived a multi-level stakeholder analysis and tried to involve those identified as relevant. Applying different means and aiming at different depth of involvement, the effort can be judged successful. The paper describes the methods used to identify and classify stakeholders, and key elements of the stakeholder management, guided by the BiodivERsA Stakeholder Activation Handbook. While on the local level, farmers and extension workers turned out to be influential and interested stakeholders in both countries, as well as local (PH) or provincial authorities (VN), differences were manifest on higher levels due to the divergent institutional setting. National-level agents were hard to get interested in both countries, and influential agents along the production chain, including middle men, were not really interested in collaboration. 相似文献