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101.
102.
Natural feline coronavirus (FCoV) infection has been shown to not only induce intestinal infection with viral shedding, but also systemic infection which either remains without clinical signs or leads to feline infectious peritonitis (FIP). As systemic infection is not the key event in the development of FIP, the question arises as to whether a potential difference in viral load might be of importance. Therefore, the purpose of this study was to quantitatively assess feline coronavirus (FCoV) RNA loads in haemolymphatic tissues of healthy, long-term FCoV-infected cats and cats with FIP. In cats that died from FIP, viral loads were significantly higher, indicating a higher rate of viral replication or a reduced capacity for viral clearance in cats developing and/or suffering from FIP. 相似文献
103.
104.
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
105.
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
106.
D. Callo-Concha M. Denich M. M. Ul Hassan F. Place D. A. Wardell 《Agroforestry Systems》2017,91(5):795-798
Since its foundation in the 1970’s, agroforestry science has evolved from setting its concepts, research approaches and flagship technologies towards its increasing contribution to ecologically sound land use, food security and income generation in the global North and South. The Third World Congress on Agroforestry held in Delhi in April 2014 continued contributed to this evolution by focusing, beyond the scientific realm, on the implementation of findings by convening ad-hoc stakeholders and subjects. Accordingly, some of the congress sessions dealt with key aspects of how agroforestry can foster and contribute to development. The special issue “Lessons for research, capacity development and policy in agroforestry for development” compiles approaches, experiences and overall lessons from (i) research, (ii) capacity development, and (iii) policy-making, capable to promote and generate developmental change through agroforestry. This introductory paper outlines the rationale for the three areas and the contributing articles. 相似文献
107.
Irauschek Florian Rammer Werner Lexer Manfred J. 《European Journal of Forest Research》2017,136(5-6):1051-1069
European Journal of Forest Research - Future provisioning of ecosystem services (ES) from mountain forests is uncertain due to potential impacts of climate change. For a case study catchment in the... 相似文献
108.
Bittrich E Rodenhausen KB Eichhorn KJ Hofmann T Schubert M Stamm M Uhlmann P 《Biointerphases》2010,5(4):159-167
With a coupled spectroscopic ellipsometry-quartz crystal microbalance with dissipation (QCM-D) experimental setup, quantitative information can be obtained about the amount of buffer components (water molecules and ions) coupled to a poly(acrylic acid) (PAA) brush surface in swelling and protein adsorption processes. PAA Guiselin brushes with more than one anchoring point per single polymer chain were prepared. For the swollen brushes a high amount of buffer was found to be coupled to the brush-solution interface in addition to the content of buffer inside the brush layer. Upon adsorption of bovine serum albumin the further incorporation of buffer molecules into the protein-brush layer was monitored at overall electrostatic attractive conditions [below the protein isolectric poimt (IEP)] and electrostatic repulsive conditions (above the protein IEP), and the shear viscosity of the combined polymer-protein layer was evaluated from QCM-D data. For adsorption at the "wrong side" of the IEP an incorporation of excess buffer molecules was observed, indicating an adjustment of charges in the combined polymer-protein layer. Desorption of protein at pH 7.6 led to a very high stretching of the polymer-protein layer with additional incorporation of high amounts of buffer, reflecting the increase of negative charges on the protein molecules at this elevated pH. 相似文献
109.
<正>水便综合征对家禽生产造成的的影响是巨大的。除了疾病,饲料质量、垫料和环境温度,包括通风都对粪便质量产生影响。其中,饲料的影响是主要因素之一。非淀粉多糖酶早就作为饲料添加剂应用于改善水便综合征,另外一个可能的 相似文献
110.
Renovation of grassland may increase the mineralization of organic material and leads to a high amount of mineral N in soil which can be leached in the winter period. Soil mineral N (SMN) in autumn and calculated nitrate leaching during winter were measured after the renewal of 8 y–old cut grassland on a sandy soil in NW Germany in 1999 to 2002. Several factors, which may influence the intensity of N mineralization, were investigated in the 2 years following renewal: the season of renovation (spring or late summer/early autumn), the technique (rotary cultivator or direct drilling), and the amount of N fertilization (0 or 320 kg N ha–1 y–1 in the 7 years before the renovation). Calculated nitrate‐N leaching losses during winter were significantly higher following renewal in early autumn (36–64 kg N ha–1) compared to renewal in spring (1–7 kg N ha–1). This effect was only significant in the first, not in the second winter after renovation. The renovation technique had a significant effect on the nitrate‐N leaching losses only in the first year after the renovation. Direct drilling led to higher leaching losses (35 kg N ha–1) than the use of a rotary cultivator (30 kg N ha–1) in the same year. Calculated nitrate losses (on average over 60 kg N ha–1) were highest after renewal of N‐fertilized grassland in late summer/early autumn. To minimize N leaching losses, it would be more effective to plan grassland renewal in spring rather than in late summer/autumn. Another, however, less effective option is to reduce N fertilization before a renovation in autumn. 相似文献