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排序方式: 共有136条查询结果,搜索用时 15 毫秒
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Silvestre García de Jalón Paul J. Burgess Anil Graves Gerardo Moreno Jim McAdam Eric Pottier Sandra Novak Valerio Bondesan Rosa Mosquera-Losada Josep Crous-Durán Joao H. N. Palma Joana A. Paulo Tania S. Oliveira Eric Cirou Yousri Hannachi Anastasia Pantera Régis Wartelle Sonja Kay Nina Malignier Philippe Van Lerberghe Penka Tsonkova Jaconette Mirck Mercedes Rois Anne Grete Kongsted Claudine Thenail Boki Luske Staffan Berg Marie Gosme Andrea Vityi 《Agroforestry Systems》2018,92(4):829-848
Whilst the benefits of agroforestry are widely recognised in tropical latitudes few studies have assessed how agroforestry is perceived in temperate latitudes. This study evaluates how stakeholders and key actors including farmers, landowners, agricultural advisors, researchers and environmentalists perceive the implementation and expansion of agroforestry in Europe. Meetings were held with 30 stakeholder groups covering different agroforestry systems in 2014 in eleven EU countries (Denmark, France, Germany, Greece, Hungary, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom). In total 344 valid responses were received to a questionnaire where stakeholders were asked to rank the positive and negative aspects of implementing agroforestry in their region. Improved biodiversity and wildlife habitats, animal health and welfare, and landscape aesthetics were seen as the main positive aspects of agroforestry. By contrast, increased labour, complexity of work, management costs and administrative burden were seen as the most important negative aspects. Overall, improving the environmental value of agriculture was seen as the main benefit of agroforestry, whilst management and socio-economic issues were seen as the greatest barriers. The great variability in the opportunities and barriers of the systems suggests enhanced adoption of agroforestry across Europe will be most likely to occur with specific initiatives for each type of system. 相似文献
83.
Tânia Luz Palma Mbagag Neba Donaldben Maria Clara Costa Jorge Dias Carlier 《Water, air, and soil pollution》2018,229(6):200
Paracetamol, the most widely and globally used analgesic and antipyretic, is easily accumulated in aquatic environments. In the present study, the biodegradation of paracetamol in different media (one for general growth, one specific for sulfate reducing bacteria, a mineral salts medium and municipal wastewater) inoculated with two types of sludge (from anaerobic lagoon and from oxidation ditch) under different oxygenic conditions (anoxic; moderate oxygenation in open flasks and high oxygenation by aeration) was investigated. In addition, bacteria with relative abundances increasing simultaneously with paracetamol degradation, when this drug was the only carbon source, thus with a putative role in its degradation, were identified using 16S rRNA gene sequences. The results show that aerobic microorganisms had a major role in the degradation of paracetamol, with 50 mg/L totally removed from municipal wastewater after 2 days incubation with aeration, and that the metabolites 4-aminophenol and hydroquinone plus one compound not identified in this work were produced in the process. The identification of bacteria with a role in the degradation of paracetamol revealed a strain from genus Pseudomonas with the highest final relative abundance of 21.2%, confirming previous works reporting strains of this genus as paracetamol decomposers. Besides, genera Flavobacterium, Dokdonella and Methylophilus were also in evidence, with initial relative abundances of 1.66%, 1.48 and 0.00% (not detected) in the inoculum and 6.91%, 3.80 and 3.83% after incubation, respectively. Therefore, a putative role of these genera in paracetamol biodegradation is suggested for the first time. 相似文献
84.
Zanetti F Mattiello R Garbino C Kaloghlian A Terrera MV Boviez J Palma E Carrillo E Berinstein A 《Avian diseases》2001,45(3):567-571
In this report, we describe the biological and molecular characterization of a paramyxovirus type-1 (PPMV-1) isolate found in wild pigeons in an urban habitat in Buenos Aires, Argentina. Of the nine pigeons captured, three were moribund, and the other six showed diarrhea, ataxia, tremor, torticolis, and wing paralysis. The intracerebral pathogenicity index was 1.29, and the amino acid (aa) sequence at the fusion protein cleavage site was 112GRQ KRF117. These characteristics correspond to a virulent Newcastle disease virus isolate. Nevertheless, it was not possible to reproduce the disease in chickens experimentally although the chickens exhibited seroconversion after inoculation. On the other hand, pigeons inoculated with the isolate became sick. These results provide further evidence about the unusual pathogenicity of PPMV-1 for chickens and show once more the need for more biological determinations in these cases to arrive at a final conclusion. 相似文献
85.
There has been much emphasis placed on the economic contribution that non-timber forest products (NTFP) can make to rural
livelihoods of people living in or near forests. In this study we focus on the benefits of greenery obtained from two tree
species, romerillo (Lomatia ferruginea (Cav.) R. Br.) and avellano (Gevuina avellana Mol.), collected by indigenous women in southern Chile. Trees producing commercial-quality leaves grew in secondary forests
dominated by species usually abundant in ecological formations that follow forest degradation. Natural availability of greenery
was relatively low (658 and 38 commercial leaves per hectare for romerillo and avellano, respectively) which added to restrictive
market conditions resulted in modest financial returns and a contribution to household income of less than 1%. Our results
confirm that trade on NTFP does not always lead to significant income generation. Yet, the information provided, represents
a basis to explore management alternatives, such as agroforestry schemes, which can potentially expand greenery yield and
economic returns. 相似文献
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Oestrus Synchronization Treatment Induces Histomorphological Changes on the Uterine Tube Epithelium of the Gilt 下载免费PDF全文
M. L. Juárez‐Mosqueda S. R. Anzaldúa Arce I. Palma Lara C. García Dalmán M. A. Cornejo Cortés A. Córdova Izquierdo H. Villaseñor Gaona M. E. Trujillo Ortega 《Anatomia, histologia, embryologia》2015,44(6):441-451
The aim of this study was to determine the histomorphological changes that occurred in response to two treatments for oestrus synchronization in three different regions of the gilt's uterine tubes epithelium: the ampulla (AMP), ampulla–isthmic junction (AIJ) and isthmus (IST). Nine prepuberal gilts were divided into three groups (n = 3): (1) eCG 400 IU and hCG 200 IU (eCG/hCG), (2) progesterone agonist (P4) and (3) control group. The number of secretory cells (stained with periodic acid–Schiff reaction or PAS‐positive cells) decreased in the AMP in the P4 treated group when compared to the control group, whereas, no difference was observed in the number of PAS‐negative cells in the AMP of the three groups. A significant decrease in the number of PAS‐positive cells was observed in the AIJ and IST of the P4 treated group when compared to the eCG/hCG and control groups. An increase in the number of PAS‐negative cells was observed in the AIJ and IST in the P4 treated group. The epithelium height in the AMP and AIJ was increased in the eCG/hCG group when compared to the control and P4 groups. In this last group, we observed a reduced height compared with the other two groups for the AIJ. In the IST, there were no significant changes in the epithelium height of the control or the other two groups (eCG/hCG and P4). The epithelial cells of the P4 treated group had the least amount of cytoplasmic granules and the lowest intensity of PAS staining in the AMP, AIJ and IST. Animals treated with eCG/hCG showed an intermediate number of cytoplasmic granules and intensity in all regions evaluated. These data show that P4 treatment for synchronization induces a significant (P < 0.001) decrease of PAS‐positive cells and staining intensity of cytoplasmic granules in the different regions studied and an increased number of PAS‐negative cells in the AIJ and IST epithelium. Moreover, eCG/hCG treatment increased the height of the epithelium in the AMP and AIJ, while in this last region, the P4 treatment decreased the epithelium height. These results show that synchronization treatments with P4 and in a smaller proportion with eCG/hCG can modify the amount of PAS‐positive and PAS‐negative cells, and the epithelium height. This has influence in the secretory activity of the epithelium and possibly alters the fluid microenvironment of the gilt's uterine tube. The biological impact of regional variations in the epithelial cells of the gilt′s uterine tube needs further investigation to understand the implications that the reproductive processes can have in the uterine tube. 相似文献
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Marty B Palma RL Pepin RO Zimmermann L Schlutter DJ Burnard PG Westphal AJ Snead CJ Bajt S Becker RH Simones JE 《Science (New York, N.Y.)》2008,319(5859):75-78
Materials trapped and preserved in comets date from the earliest history of the solar system. Particles captured by the Stardust spacecraft from comet 81P/Wild 2 are indisputable cometary matter available for laboratory study. Here we report measurements of noble gases in Stardust material. Neon isotope ratios are within the range observed in "phase Q," a ubiquitous, primitive organic carrier of noble gases in meteorites. Helium displays 3He/4He ratios twice those in phase Q and in Jupiter's atmosphere. Abundances per gram are surprisingly large, suggesting implantation by ion irradiation. The gases are probably carried in high-temperature igneous grains similar to particles found in other Stardust studies. Collectively, the evidence points to gas acquisition in a hot, high ion-flux nebular environment close to the young Sun. 相似文献