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231.
In order to avoid the occurrence of boar taint, castration of piglets without pain relief is a common practice in pork production. Due to increasing animal welfare concerns, the practice will be banned in organic agriculture from 2012 and alternative methods will have to be implemented. An important factor for the successful implementation of such alternatives is consumers’ acceptance of the methods, as consumers’ daily buying decisions are crucial to the further development of the organic pork sector. Thus, this paper explores organic consumers’ attitudes towards piglet castration without pain relief and three alternative methods and examines which aspects of these alternatives are important to consumers of organic products. The analysis of nine focus group discussions in Germany conducted in fall 2009 and involving a total of 89 participants, shows that castration without pain relief in organic farming was unacceptable for participants. Animal welfare, food safety, taste, and costs were principal aspects that participants used to assess the three alternatives. Participants had mainly favorable attitudes towards castration with anesthesia and analgesia. Although participants had some concerns regarding the fattening of boars (taste), there was openness towards this alternative due to its perceived naturalness. Immunocastration was seen quite critically because participants feared that this alternative might lead to (hormone) residues in meat. Overall, the results suggest that fattening of boars and castration with anesthesia and analgesia could be acceptable alternatives to consumers of organic pork. 相似文献
232.
Carbamazepine (CBZ), caffeine and cetirizine were monitored by enzyme-linked immunosorbent assays (ELISAs) in surface and wastewaters from Berlin, Germany. This fast and cost-efficient method enabled to assess the spatial and temporal variation of these anthropogenic markers in a high-throughput screening. CBZ and cetirizine were detected by the same antibody, which selectively discriminates between both compounds depending on the pH value used in the incubation step. To our best knowledge, this is the first dual-analyte immunoassay working with a single antibody.The frequent sampling with 487 samples being processed allowed for the repeated detection of unusually high concentrations of CBZ and caffeine. ELISA results correlate well with the ones obtained by liquid chromatography tandem mass spectrometry (LC-MS/MS). Caffeine concentrations found in surface waters were elevated by combined sewer overflows after stormwater events. During the hay fever season, the concentrations of the antihistamine drug cetirizine increased in both surface and wastewaters.Caffeine was almost completely removed during wastewater treatment, while CBZ and cetirizine were found to be more persistent. The maximum concentrations of caffeine, CBZ and cetirizine found in influent wastewater by LC-MS/MS were 470, 5.0 and 0.49 μg L−1, while in effluent wastewater the concentrations were 0.22, 4.5 and 0.51 μg L−1, respectively. For surface waters, concentrations up to 3.3, 4.5 and 0.72 μg L−1 were found, respectively. 相似文献
233.
234.
In Germany, there is a lack of consistent and comparable data for the time dependent behaviour and spatial distribution of dioxin-like and indicator PCB in ambient air, deposition and plants. The aim of this study was to improve the data on PCDD/PCDF, dioxin-like PCB and non dioxin-like PCB in spruce and pine shoots from different locations and years by retrospective monitoring. The survey was conducted with archived samples of one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) from the German environmental specimen bank. Two sets of samples from locations in urbanized areas in western and eastern Germany (Warndt and Duebener Heide Mitte, respectively) were investigated as time series. Additionally, spruce shoots from seven different rural locations sampled in the years 2000-2004 were analyzed in order to get an overview about the spatial distribution of PCB and PCDD/PCDF. The analytical results of the samples from the two urbanized areas clearly show that the atmospheric contamination with PCDD and PCDF has declined by about 75% between 1985 and 1997 at Warndt and about 40% between 1991 and 1997 at Duebener Heide. However, concentrations stayed virtually constant at both locations from 1997 to 2004 at a level of about 1 ng WHO-TEQ/kg dry matter (d.m.). Similarly, the investigation of spruce shoots from rural locations from 2000 to 2004 did not reveal a temporal trend at any site. PCDD/PCDF levels were between 0.1 and 1.0 ng WHO-TEQ/kg d.m. At the urbanized location Warndt the six indicator PCB as well as the 12 dioxin-like PCB according to WHO revealed a significant decline by more than 75% between 1985 and 1999. Thereafter, PCB levels stayed virtually constant. At the location Duebener Heide an overall decrease of PCB concentrations in pine shoots of about 60% was detected between 1991 and 2004. Spruce shoots from all locations showed a relevant contribution of dioxin-like PCB to the total WHO toxicity equivalent (PCDD/PCDF+PCB). In most samples, the contribution of dioxin-like PCB was between 21% and 41%. The TEQ contribution of PCB in the samples from three rural sites was higher and similar to the TEQ value of PCDD/PCDF. The investigated pine shoots from the urbanized site Duebener Heide showed a 15-28% contribution of dioxin-like PCB to total TEQ and thus lower than in spruce shoots from different locations. In all samples except one PCB 126 contributed to more than 80% to the PCB-TEQ. 相似文献
235.
The need for coordination among scientific and policy activities is an old debate in which respective communities have often tried to impose their views rather than reflecting on pragmatic solutions. In the last few years, however, constructive exchanges have taken place in the context of expert groups linked to the implementation of the Water Framework Directive (WFD) and related EU funded research projects, which have resulted in a better understanding of communication and knowledge transfer gaps. These exchanges concern not only the way research is being interfaced with water policies, but also how improved coordination could be organised regarding technical specifications linked to standardisation. This paper discusses on-going efforts to improve coordination among research, standardisation and policy in support of WFD implementation, with emphasis on chemical monitoring requirements. 相似文献
236.
Erich Zeeck Carsten T. Müller Manfred Beckmann Jörg D. Hardege Ulrich Papke Volker Sinnwell Frank C. Schroeder Wittko Francke 《Chemoecology》1998,8(1):33-38
Summary. In the marine polychaete Nereis succinea (Frey & Leuckart 1847) a sex pheromone was isolated from the coelomic fluid of sexually mature females and identified by
NMR studies and independent synthesis. This pheromone is released by the females during reproduction together with eggs and
coelomic fluid into the free water column and induces sperm release of surrounding males. Its structure was ascertained as
L-cysteine-glutathione disulfide. It exhibited a response threshold of 0.6 · 10−7 M.
Received 15 July 1997; accepted 25 November 1997. 相似文献
237.
238.
Holger Brackemann Ulrich Hagendorf Jürgen Hahn Ute Vogel 《Environmental Sciences Europe》2000,12(1):5-12
Wastes from three different types of waste treatment facilities (slag from a municipal waste incineration plant, slag granules from a pilot plant combining carbonization and incineration, mechanical and biological treated wastes) were examined to determine their hazard potential to different waters sites. The process temperature is seen to be the main difference between the three treatment processes. The wastes were extracted with water according to the German standard DIN 38414 S 4 and additionally at a constant pH value of 4. The leachates were investigated in a battery of aquatic bioassays and characterised physically and chemically. Every leachate revealed in a toxic effect at least in one test. The toxicity of the leachates prepared at a pH of 4 was significantly higher than the toxicity of the leachates prepared by extraction with water without pH adjustment. The leachates of the slag granules showed the lowest toxicity. On the basis of these experimental results, a scheme to derive Water Hazard Classes of wastes, which is presented in part II of this publication, was developed. 相似文献
239.
Uta Berger Marion Glaser Boris Koch Gesche Krause Rubén Lara Ulrich Saint-Paul Dirk Schories Matthias Wolff 《Journal of Coastal Conservation》1999,5(2):125-134
The main objective of the MADAM project (Mangrove Dynamics and Management) is to generate the scientific basis enabling the
sustainable stewardship of the resources of the Caeté mangrove estuary in Northeast Brazil in the sense of integrated coastal
(zone) management. To achieve this, it is necessary to acquire in-depth knowledge of natural processes as well as of the relevant
institutional, cultural, economic, social and political dynamics. Causal linkages within the ecosystem, as well as between
ecosystem, economy and society, are analysed and explained via dynamic and trophic modelling. Scenario construction is intended
to forecast the effects of acute or chronic interference on utilized resources, and to answer wider, management-related questions
(e.g. restoration of destroyed areas, utilization potential for aquaculture). This paper describes the project strategy as
developed and modified in the context of research results from the initial 2-yr project phase. It is argued that a continuous
discussion process is essential to assess the validity of the strategies formulated at the beginning of a medium-time project,
particularly if the project is of interdisciplinary nature. 相似文献
240.
Henner Hollert Susanne Heise Steffen Keiter Peter Heininger Ulrich Förstner 《Environmental Sciences Europe》2007,19(1):58-70