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排序方式: 共有244条查询结果,搜索用时 250 毫秒
1.
Santana Pedro Henrique Lopes Burak Diego Lang Thiengo Cássio Carlette Peçanha Anderson Lopes Neves Mirna Aparecida Mendonça Eduardo de Sá 《Journal of Soils and Sediments》2020,20(11):4103-4110
Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for... 相似文献
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Vernica da Silva Oliveira Meringela Miranda da Cruz Gabriela Suassuna Bezerra Natan Emanuell Sobral e Silva Fernando Henrique Andrade Nogueira Guilherme Maranho Chaves Jos Lamartine Soares Sobrinho Francisco Jaime Bezerra Mendona-Junior Bolívar Ponciano Goulart de Lima Damasceno Attilio Converti dley Antonini Neves de Lima 《Marine drugs》2022,20(2)
In this study, films of chitosan and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (6CN), a 2-aminothiophene derivative with great pharmacological potential, were prepared as a system for a topical formulation. 6CN-chitosan films were characterized by physicochemical analyses, such as Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Additionally, the antifungal potential of the films was evaluated in vitro against three species of Candida (C. albicans, C. tropicalis, and C. parapsilosis). The results of the FTIR and thermal analysis showed the incorporation of 6CN in the polymer matrix. In the diffractogram, the 6CN-chitosan films exhibited diffraction halos that were characteristic of amorphous structures, while the micrographs showed that 6CN particles were dispersed in the chitosan matrix, exhibiting pores and cracks on the film surface. In addition, the results of antifungal investigation demonstrated that 6CN-chitosan films were effective against Candida species showing potential for application as a new antifungal drug. 相似文献
3.
Sigauque I Van den Bossche P Moiana M Jamal S Neves L 《The Onderstepoort journal of veterinary research》2000,67(3):167-172
A tsetse and bovine trypanosomosis survey was conducted during 1998 and 1999 in the Matutuine District of Maputo Province (Mozambique). A total of 59 Glossina brevipalpis and 17 Glossina austeni were captured throughout the district. Survey results suggest that Glossina brevipalpis is mainly concentrated in dense vegetation along the Maputo River and in the wetlands east of the river. G. austeni, on the other hand, was captured mainly in dense thickets in drier areas. Both tsetse species are suspected to be vectors of bovine trypanosomosis. Bovine trypanosomosis (75,5% Trypanosoma congolense) was diagnosed in 53 animals (13,9%) from seven sampling sites distributed throughout the district. The prevalence of cattle with anti-trypanosomal antibodies was high (29,9%).The incidence of trypanosomal infections in sentinel cattle was also high. The widespread distribution of bovine trypanosomosis and the high prevalence of infection are likely to have a significant impact on cattle production and, hence, the cattle restocking exercise in the district. 相似文献
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Summary Differences between isogenic uptake hydrogenase (HUP) mutants of Bradyrhizobium japonicum in terms of nodule efficiency, N2 fixation and N incorporation into various plant parts were studied in a monoxenic greenhouse experiment in order to confirm previous results with soybeans and beans inoculated with various HUP+ and HUP– strains. The HUP+ revertant PJ17-1 of a HUP– mutant (PJ17) of strain USDA DES 122 showed a completely restored relative efficiency (100% versus 78±2% for the HUP– mutant), higher nodule efficiency (N2 fixed per g nodules), higher ureide-N transport rates, higher N contents in pods and higher N harvest indices. All these observations confirm previous experiments with HUP+ and HUP– strains. 相似文献
8.
Quantitative data were obtained for arboreal species within 50 lowland forests in southeastern Ohio. Thirty-seven communities were dominated by Betula nigra L. and 13 were dominated by Acer saccharinum L. The acidic soils collected from B. nigra communities contained toxic concentrations of exchangeable Al and low concentrations of Ca and Mg. Tree species diversity (Shannon-Weaver index) and species equitability were inversely related to high concentrations of exchangeable Al and H and directly related to high concentrations of exchangeable Ca and Mg and an increase in soil pH. 相似文献
9.
Jorge Nunes Manuel Madeira Luíz Gazarini José Neves Henrique Vicente 《Agroforestry Systems》2012,84(1):89-100
The changes in the soil nitrate concentration were studied during 2 years in a “montado” ecosystem, in the South of Portugal.
Total rainfall, air and soil temperature and soil water content under and outside Quercus rotundifolia canopy were also evaluated. A cluster analysis was carried out using climatic and microclimatic parameters in order to maximize
the intraclass similarity and minimize the interclass similarity. It was used the k-Means Clustering Method. Several cluster
models were developed using k values ranging between 2 and 5. Thereafter, in each cluster, the data were divided according
to their origin (soil under canopy and open areas, and from surface and deep layers). Multiple regression models were tested
for each cluster, to assess the relationship between soil nitrate concentration and a set of climatic and microclimatic parameters
and the results were compared with models assessed without clustering. The models achieved with data grouped in result of
clustering analysis showed better performance than the models achieved without clustering, mostly for data from open areas
soils. When temperature is low and/or water presents excess or scarcity levels, the data from soils in undercanopy areas,
give rise to models with worst performance than models from open soil areas data. The results obtained for undercanopy area
suggest that nitrification process in soil under Quercus rotundifolia trees influence is more complex than for open areas, and subject to other relevant factors beyond water and temperature. 相似文献
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