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41.
Marta Salgueiro Alves Anabela Pereira Cludia Vicente Manuel Mota Isabel Henriques 《Forest Pathology》2019,49(6)
In this study, we characterized the diversity of Pseudomonas associated with Bursaphelenchus xylophilus, its insect vector (Monochamus galloprovincialis) and its host (Pinus pinaster), by a culture‐independent approach using rpoD clone libraries. Clone libraries of Pseudomonas rpoD were obtained from B. xylophilus, M. galloprovincialis and infected P. pinaster. Most M. galloprovincialis and B. xylophilus sequences grouped together in the P. fluorescens group. Genes related to xenobiotics degradation and phenylacetate synthesis were present in the genomes of the type strains closely related to sequences retrieved from the nematode libraries. Results demonstrated that the nematode, during its life stages inside the tree, maintains a diverse Pseudomonas community that is closely related to the one associated with the insect vector. These bacteria might contribute to degradation of xenobiotics and tree weakening during the nematode tree infection. 相似文献
42.
43.
Rita Bastos António T. Monteiro Diogo Carvalho Carla Gomes Paulo Travassos João P. Honrado Mário Santos João Alexandre Cabral 《Landscape Ecology》2016,31(4):701-710
Context
Land-use/land-cover (LU/LC) dynamics is one of the main drivers of global environmental change. In the last years, aerial and satellite imagery have been increasingly used to monitor the spatial extent of changes in LU/LC, deriving relevant biophysical parameters (i.e. primary productivity, climate and habitat structure) that have clear implications in determining spatial and temporal patterns of biodiversity, landscape composition and ecosystem services.Objectives
An innovative hierarchical modelling framework was developed in order to address the influence of nested attributes of LU/LC on community-based ecological indicators.Methods
Founded in the principles of the spatially explicit stochastic dynamic methodology (StDM), the proposed methodological advances are supported by the added value of integrating bottom-up interactions between multi-scaled drivers.Results
The dynamics of biophysical multi-attributes of fine-scale subsystem properties are incorporated to inform dynamic patterns at upper hierarchical levels. Since the most relevant trends associated with LU/LC changes are explicitly modelled within the StDM framework, the ecological indicators’ response can be predicted under different social-economic scenarios and site-specific management actions. A demonstrative application is described to illustrate the framework methodological steps, supporting the theoretic principles previously presented.Conclusions
We outline the proposed multi-model framework as a promising tool to integrate relevant biophysical information to support ecosystem management and decision-making.44.
Rita Constantino Miguel B. Gaspar Fábio Pereira Susana Carvalho João Cúrdia Domitília Matias Carlos C. Monteiro 《水产资源保护:海洋与淡水生态系统》2009,19(5):542-553
- 1. Razor clams are found in different habitats ranging from sheltered systems (e.g. lagoons and estuaries) to open coasts. They are distributed worldwide and comprise a small number of species of high economic value. Depending on the specific habitat and species exploited, different mechanical and hand‐harvesting techniques are employed. While the environmental effects resulting from mechanized methods have been described by several authors, the impacts caused by traditional hand‐harvesting methods remain unknown. Therefore, a study was undertaken in Ria Formosa lagoon (South of Portugal) addressing the environmental effects resulting from harvesting Solen marginatus with salt.
- 2. No significant impact on the sediment was found; the main effect was an increase in salinity after covering the area with salt, which decreased rapidly with the flood tide and after a few hours had returned to pre‐harvesting levels.
- 3. No effects on benthic communities were observed, with similar fluctuation patterns recorded in control and experimental areas, the observed differences being attributed to the natural variability of benthic populations.
- 4. Based on the results obtained in the present study, a razor clam fishery using salt in intertidal areas can be considered environmentally ‘friendly’.
45.
Victor JV Rossetto Lígia SLS da Mota Noeme S Rocha Hélio A Miot Fabrizio Grandi Cláudia VS Brand?o 《Acta veterinaria Scandinavica》2013,55(1):39
Background
Due to numerous complications associated to gastrointestinal augmented cystoplasty, this study aimed to analyze the anatomic repair of the bladder of 10 female dogs using grafts of porcine small intestinal submucosa (SIS) seeded with cultured homologous smooth muscle cells, and compare them with the acellular SIS grafts.Results
We assessed the possible side effects and complications of each type of graft by clinical examination, abdominal ultrasound and laboratory findings. Anatomic repair of neoformed bladder was assessed by histological staining for H/E and Masson''s Trichrome, analyzed with a Nikon Photomicroscope connected to the system of image analysis Image J.Conclusions
We propose that SIS associated to homologous smooth cells can improve the quality of tissue repair, and consequently decrease the potential complications inherent to acellular SIS. 相似文献46.
Bergamasco Rde C Zanin GM de Moraes FF 《Journal of agricultural and food chemistry》2005,53(4):1139-1143
Sulfluramid is an expensive active principle of insecticidal baits that is lost by volatilization during the pelletization of baits. To increase the thermal stability of sulfluramid, we tested its molecular encapsulation in beta-cyclodextrin (beta-CD), using molar ratios of 1:1 and 1:2 (sulfluramid:beta-CD), using the complex preparation techniques of coprecipitation and kneading. The physical mixture of sulfluramid and beta-CD was also tested for comparison. The products of complexation were characterized by differential scanning calorimetry, thermogravimetry, and derivative thermogravimetry, indicating the formation of a sulfluramid/beta-CD complex and showing that the release of the complexed sulfluramid occurs in the range of 270-300 degrees C, a temperature range that is well above the temperature at which sulfluramid sublimates (40 degrees C). This result warrants a reduced sulfluramid loss in the preparation of insecticidal baits. The preparation of the complex by kneading with molar ratio of 1:2 gave the highest yield of complex, about 64%, in relation to the theoretical maximum. 相似文献
47.
Erin Nelson Laura Gómez Tovar Rita Schwentesius Rindermann Manuel Ángel Gómez Cruz 《Agriculture and Human Values》2010,27(2):227-237
Over the past two decades the growth of the organic sector has been accompanied by a shift away from first party, or peer
review, systems of certification and towards third party certification, in which a disinterested party is responsible for
the development of organic standards and the verification of producer compliance. This paper explores some of the limitations
of the third party certification model and presents the case of Mexico as an example of how an alternative form of participatory
certification has emerged. The paper suggests that participatory guarantee systems (PGS) are reflective of the growing “beyond
organic” movement, which focuses on reconstructing the local and re-embedding food systems into their socio-ecological contexts.
It argues that PGS offers a number of benefits for producers and consumers, particularly in the South, but that it faces a
number of challenges as well, such as a lack of formal recognition, social conflicts and dependence on donated resources. 相似文献
48.
49.
Santamaria AR Mulinacci N Valletta A Innocenti M Pasqua G 《Journal of agricultural and food chemistry》2011,59(17):9094-9101
Methyl jasmonate, jasmonic acid and chitosan were tested as elicitors on cell suspension cultures obtained from Vitis vinifera cv Italia to investigate their effect on stilbene production. Stilbene accumulation in the callus, grown under nonelicited conditions, was also investigated. Calli and cell suspensions were obtained in a B5 culture medium supplemented with 0.2 mg L(-1) NAA and 1 mg L(-1) KIN. Stilbene determination was achieved by HPLC/DAD/MS. Whereas callus biosynthesized only piceid, cell suspensions elicited with jasmonates produced several stilbenes, mainly viniferins. In suspended cells, methyl jasmonate and jasmonic acid were the most effective in stimulating stilbene biosynthesis, whereas chitosan was less effective; in fact, the amount of stilbenes obtained with this elicitor was not significantly different from that obtained for the control cells. The maximum production of total stilbenes was at day 20 of culture with 0.970 and 1.023 mg g(-1) DW for MeJA and JA, respectively. 相似文献
50.
Nils Dittbrenner Hannah Schmitt Yvan Capowiez Rita Triebskorn 《Journal of Soils and Sediments》2011,11(6):1000-1010