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61.
Slurry management is a central topic in the agronomic and environmental analysis of intensive livestock production systems. The objective of this study is to compare the environmental performance of two scenarios of collective slurry management for the disposal of excess nitrogen from animal manure. The scenarios are the transfer of slurry and its injection to crop land, and the treatment of slurry in a collective biological treatment station. The study is based on a real case in the West of France, where a group of farmers is developing a collective plan for the disposal of almost 7000 m(3) of excess pig slurry. The evaluation is carried out by Life Cycle Assessment, where emissions and resource consumption are quantified and aggregated into four environmental impact categories: eutrophication, acidification, climate change, and non-renewable energy use. Ammonia emitted is the most important contributor to acidification and eutrophication, while methane contributes most to climate change. Both ammonia and methane are mostly emitted during the storage of slurry and, in the case of the treatment scenario, also during composting the solid fraction of the slurry. The two management strategies are similar with respect to climate change, whereas eutrophication and acidification are twice as large for treatment relative to transfer. Electricity needed for the treatment process is the main contributor to non-renewable energy use for the treatment scenario, while the transfer scenario represents a net energy saving, as energy saved by the reduction of mineral fertiliser use more than compensates for the energy needed for transport and injection of slurry. The overall environmental performance of transfer is better than that of treatment, as it involves less acidification, eutrophication and non-renewable energy use. The method employed and the results obtained in this study can provide elements for a transparent discussion of the advantages and disadvantages of contrasting excess slurry management scenarios as well as the identification of the main aspects determining their environmental performance.  相似文献   
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In this paper we examine the effect of Gross Domestic Product (GDP) on the level of fish intake in China in comparison with the rest of the world. We also analyse the origin and destination of China’s seafood products in order to understand the main patterns during the last decades. The results show that in the 1961–2011 period the rate of growth of the GDP in China doubled that of other developing regions, while the daily fish intake of China increased fourfold, making China the largest fish consumer in the world. Given the size and scale of China’s role in production, consumption, and global transformation of seafood markets, China is shaping a new era of industrialization in the history of the fishing industry.  相似文献   
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An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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The bioremediation of a long-term contaminated soil through biostimulation and surfactant addition was evaluated. The concentrations of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) and its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE) were monitored during an 8-week remediation process. Physicochemical characterization of the treated soil was performed before and after the bioremediation process. The isolation and identification of predominant microorganisms during the remediation process were also carried out. The efficiency of detoxification was evaluated after each bioremediation protocol. Humidity and pH and the heterotrophic microorganism count were monitored weekly. The DDT concentration was reduced by 79% after 8 weeks via biostimulation with surfactant addition (B + S) and 94.3% via biostimulation alone (B). Likewise, the concentrations of the metabolites DDE and DDD were reduced to levels below the quantification limits. The microorganisms isolated during bioremediation were identified as Bacillus thuringiensis, Flavobacterium sp., Cuprivadius sp., Variovorax soli, Phenylobacterium sp. and Lysobacter sp., among others. Analysis with scanning electron microscopy (SEM) allowed visualization of the colonization patterns of soil particles. The toxicity of the soil before and after bioremediation was evaluated using Vibrio fischeri as a bioluminescent sensor. A decrease in the toxic potential of the soil was verified by the increase of the concentration/effect relationship EC50 to 26.9% and 27.2% for B + S and B, respectively, compared to 0.4% obtained for the soil before treatment and 2.5% by natural attenuation after 8 weeks of treatment.  相似文献   
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Inversions are structural chromosome abnormalities that may be associated with infertility, multiple miscarriage and chromosomally unbalanced offspring. Preimplantation genetic diagnosis (PGD) with subtelomeric probes was used to select for transfer only those embryos that were normal or balanced for three pericentric inversions. In contrast to previous protocols the present procedure allows the detection of unbalanced embryos that might arise from U-recombination in the inverted region. Additionally, aneuploidy screening was carried out in two cases by a second round of fluorescent in situ hybridization (FISH) with centromeric probes. Of the three couples that underwent the procedure one became pregnant twice. The first pregnancy delivered a healthy and chromosomally normal baby and the second pregnancy is ongoing with triplets. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Environmental Chemistry Letters - Most of the catalytic systems for C–C coupling reactions are based on homogeneous catalysts which are normally used only once and do not have a sustainable...  相似文献   
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Environmental Modeling & Assessment - Different linear transfer functions (TFs) models are compared to the traditional non-linear rating curve (RC) model in a novel event-based exploratory...  相似文献   
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