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. 2004. Influence of compost on the physical properties and organic matter fractions of a fine sandy loam throughout the cycle of a potato rotation. Can. J. Soil Sci. 84: 211-218. Potato (Solanum tuberosum L.) rotations often require organic amendments to maintain or improve soil organic matter levels and soil physical properties. However, beneficial effects of compost can be modified by time of application and rotating tillage depth and intensity. This study was conducted to evaluate the effect of compost applied once at different phases in a 3-yr potato, barley (Hordeum vulgare L.), and red clover (Trifolium pretense L.) rotation on a range of soil physical properties and organic matter fractions for a Charlottetown fine sandy loam (Orthic Humo-Ferric Podzol) in Prince Edward Island. Soil samples (0-8 cm) were obtained during the second cycle of the rotation (after two compost applications) in the fifth year of the experiment. Soil properties were influenced by compost addition, time of compost addition, and crop phase. Compost-induced benefits in soil physical properties (bulk density, macro-porosity, oxygen diffusion rate, shear vane strength, water-filled pore space) were mainly expressed in the red clover phase of the rotation, where soil density was relatively high compared to the barley and potato phases, due to the absence of tillage. The soil physical parameters, however, were mainly within their established optimum ranges for this soil type. Soil water content at -0.033 MPa was increased by compost in the potato phase, compared to the control. Soil organic matter was influenced by both compost and crop C inputs. Compost increased soil particulate organic matter (POM) in the potato and barley phases. Due to differences in crop residue inputs, compost-related differences in organic matter were minimized in the red clover phase of the rotation. Compost addition increased potato tuber yield above the maximum yield obtained with nitrogen application. This "non-nitrogen" compost yield effect may be related to the slight, but significant, improvement in soil water-holding capacity. Overall, compost application in an intensive 3-yr potato rotation provided benefits for potato productivity and in both soil physical and biological properties. 211-218. Les assolements avec pomme de terre (Solanum tuberosum L.) exigent souvent des amendements organiques pour que le sol garde ou améliore la quantité de matière organique et ses propriétés physiques. Toutefois, le moment de l'application ainsi que la profondeur et l'intensité des labours peuvent modifier les avantages du compost. La présente étude devait préciser les conséquences de l'application de compost à divers moments lors d'un assolement de trois ans incluant la pomme de terre, l'orge (Hordeum vulgare L.) et le trèfle rouge (Trifolium pratense L.) sur diverses propriétés physiques du sol et sur les fractions de la matière organique dans un fin loam sablonneux Charlottetown (podzol orthique humo-ferrique) de l'Île-du-Prince-Édouard. Les auteurs ont prélevé des...

We conclude that 100 mg twice a day sitafloxacin in Caucasians is associated with a mild degree of cutaneous phototoxicity. Enoxacin 200 mg three times a day and sparfloxacin 200 mg day-1 are much more photoactive. Sparfloxacin phototoxicity is induced by UVA and visible wavelengths. Levofloxacin and placebo failed to show a phototoxic effect. In the Oriental study, sitafloxacin 50 mg twice a day and 100 mg twice a day failed to demonstrate a clinically significant phototoxic effect.