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261.
Franco Gozzo Luigi Garlaschelli Pier M. Boschi Angela Zagni Jean C. Overeem Lambertus de Vries 《Pest management science》1985,16(3):277-286
The influence of structural variations in compounds of the N-acylalanine type, on their fungicidal activity towards Peronosporales, was examined. Within a series of methyl N-(acyl)-N-(2,6-xylyl)alaninates ( I ), a quantitative structure-activity relationship was given for the curative action against Plasmopara viticola, through a Hansch-type equation. A deviation from this equation is discussed with reference to benalaxyl ( I ; acyl=phenylacetyl). Syntheses and qualitative indications of activity are reported for structural changes in the xylyl and in the alanine moieties. Progress in the latter approach is briefly outlined. 相似文献
262.
Luigi d'Aquino Massimo Morgana Michele Staiano Marilena Re Francesco Vinale Sheridan L. Woo 《Soil biology & biochemistry》2009,41(12):2406-2413
Accumulation of rare earth elements (REE) in the soil may be due to the use of REE enriched fertilizers and to contamination by REE containing wastes. Although widely used in China for soil and foliar dressing of crops, little is known about the effect of REE applications on the soil microbial community. The effect of REE on the growth of biological control strains of Trichoderma atroviride and Trichoderma harzianum was investigated in vitro using either a mix of different REE containing different amounts of lanthanum, cerium, praseodymium, neodymium, gadolinium nitrate and lanthanum nitrate alone in comparison to treatments with potassium nitrate and water. In plate tests applied concentrations ranged from 0.1 mM to 300 mM for lanthanum and REE mix and from 0.1 mM to 900 mM for the potassium solution. In liquid culture tests applied concentrations ranged from 0.001 mM to 100 mM for lanthanum and REE mix and from 0.003 mM to 900 mM for the potassium solution. ICP-MS, TEM and TEM X-ray microanalysis were used to study the accumulation of REE in fungal biomass. All the Trichoderma strains showed a good tolerance to the presence of REE in the culture media. Some growth enhancing effects were observed in liquid cultures of T. harzianum strains but not in T. atroviride. Accumulation of REE in fungal biomass, both at intracellular level and in the extracellular matrix, was observed. 相似文献
263.
Column Elution Experiments on Volcanic Ash: Geochemical Implications for the Main Ethiopian Rift Waters 总被引:1,自引:0,他引:1
Tewodros Rango Nicolò Colombani Micòl Mastrocicco Gianluca Bianchini Luigi Beccaluva 《Water, air, and soil pollution》2010,208(1-4):221-233
Column laboratory experiments were employed to assess the leaching behaviour of pyroclastic glassy ash deposits collected in the central Main Ethiopian Rift, where surface and groundwater resources are affected by fluoride (F?) pollution, which is the cause of an endemic disease (fluorosis) in the local community. To elucidate the source of F? and simulate the water–rock interaction processes, as well as quantify its distribution within different grain sizes, the pyroclastic ash was analysed by XRF, XRD and SEM and separated into coarse and fine fractions. Three columns were filled with raw (unsieved), coarse (63 μm–2 mm) and fine (<63 μm) fraction, respectively, and flushed with synthetic rain water in saturated conditions. Very fast F? leaching was observed in the fine fraction column at the start of the experiment, while in the other two columns, F? was slowly released; in addition, a strong accumulation of F? was found in the fine fraction. The effect was more pronounced in the fine fraction column due to the available effective adsorbing surface area. Subsequent to elution experiments, the columns were characterised via moment analysis of tracer test. Finally, flow and transport modelling (MODFLOW-2000 and MT3DMS) was employed to compute the amount of F? adsorbed onto the solid phase, comparing the calculated conservative transport of F? and the observed concentrations. The results of this study suggest that fluoride is a fundamental constituent of the glass phase (about 0.3 wt.%) and that it is released during the incongruent dissolution of glassy particles. Dissolution of coatings on glass particles could provide an additional contribution to the geochemistry of the interacting fluids. These processes are more effective in the fine fraction due to a much higher reactive (specific) surface area. 相似文献
264.
Mattia Cesa Alessandro Bizzotto Claudio Ferraro Flaminio Fumagalli Pier Luigi Nimis 《Water, air, and soil pollution》2010,208(1-4):59-77
The concentration of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, V and Zn was measured in the aquatic bryophyte Rhynchostegium riparioides after a 4-week transplantation at 83 stations in seven main watercourses and three smaller tributaries of the basin of the River Bacchiglione (NE Italy). The study, carried out in 9 months, aimed at establishing a database for statistical analyses to define a novel index of water quality, specifically calibrated for moss bags, and suitable for bio-monitoring purposes where autochthonous bryophytes are not available. The background level was estimated for each element, the ratio between sample and background concentration was adopted as measure of environmental alteration and a five-class interpretation scale was defined. The 73.8% of measured concentrations reflected a condition of naturality, 16.6% suspect of alteration, 7.6% sure alteration, 1.6% severe alteration and <0.5% extreme alteration. The condition of global environmental alteration (all contaminants) at each station was also defined. Forty-four stations presented absence or suspect of alteration, 39 sure alteration for one or more elements. Bivariate and multivariate analyses revealed (1) highly significant correlations (p?<?0.001) between the concentrations of Co–Mn, Sb–Zn, and Fe–V, depending on both natural and human factors, (2) chemical patterns leading to galvanic industries, metallurgy or urban sewages, in some case with a geographical distribution and (3) a gradient of environmental alteration from the Pre-Alps to the lowland. Coloured maps indicate both point sources and widespread environmental alteration, highlighting not only industrial–urban areas but also some apparently undisturbed sites. 相似文献
265.
266.
267.
Fortunati Elena Rescignano Nicoletta Botticella Ermelinda La Fiandra Domenico Renzi Marsilio Mazzaglia Angelo Torre Luigi Kenny Josè Maria Balestra Giorgio Mariano 《植物病害和植物保护杂志》2016,123(6):301-310
Journal of Plant Diseases and Protection - Nanotechnology can change the scenario of current tools minimizing the chemical inputs in plant protection. Here, novel poly(dl-lactide-co-glycolide acid)... 相似文献
268.
Dell'Orco M Bertazzolo W Pagliaro L Roccabianca P Comazzi S 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(3):264-269
A 3-year-old, spayed, female Boxer was presented because of acute onset of anorexia, vomiting, and hemorrhagic diarrhea. Microangiopathic hemolytic anemia with intravascular hemolysis, thrombocytopenia, and acute renal failure were detected. The dog was treated with fluids, antiemetics, antibiotics, and diuretics. Despite supportive therapy, the dog's condition worsened, and the owners elected euthanasia. Necropsy revealed disseminated petechiae on the parietal peritoneum and serosal surfaces of the intestinal tract. The histologic lesions were consistent with severe arteritis and microvascular thrombosis involving only the renal and intestinal arterioles. The final diagnosis was hemolytic-uremic syndrome (HUS), a rarely described disorder in dogs. The clinical presentation of primarily gastrointestinal clinical signs was similar to that of typical or diarrhea-associated HUS (D+ HUS) in humans (mainly children), which is caused by gastrointestinal proliferation of verocytotoxin-producing Escherichia coli. Bacterial toxins can be adsorbed and cause endothelial injury, activation of hemostasis, and thrombosis, with lesions confined primarily to the kidneys. Although rare, HUS should be considered in the differential diagnosis of dogs with microangiopathic hemolytic anemia. 相似文献
269.
270.
Changes in land-use/land-cover patterns in Italy and their implications for biodiversity conservation 总被引:2,自引:0,他引:2
Land-use/land-cover change is the most important factor in causing biodiversity loss. The Mediterranean region has been affected
by antropic disturbance for thousands of years, and is, nowadays, one of the most significantly altered hotspots in the world.
However, in the last years a significant increase in forest cover has been measured. These new patterns are independent from
planned conservation strategies and appear to have a substantial impact on landscapes and biodiversity. We used three land-use/land-cover
maps (from 1960 to 2000) covering the Italian peninsula to analyze the pattern of land-use/land-cover change. We measured
an increase in forests, especially in mountains, an increase in artificial areas, especially in coastal zones, and a decrease
in pastures. Intensively cultivated areas showed a limited decrease while extensively cultivated ones showed a marked decrease.
In the same period mammal and bird species followed a similar pattern, with forest birds, ungulates and carnivores increasing,
and typically Mediterranean species decreasing. We suggest that our results may provide important information, which could
be useful for conservation planning in the entire Mediterranean hotspot. We suggest that an increasing conservation effort
should be made to protect the Mediterranean-type forests and scrublands, as well as traditional agricultural practices. Moreover,
future conservation efforts should consider the broad socio-political and ecological processes that are most likely to occur
across the whole hotspot, especially along coastal areas, and the network of protected areas should be functionally integrated
in a conservation strategy that includes the human-dominated landscape. 相似文献