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91.
Didier Noël Carlotti Pauline Guinot Etienne Meissonnier Pierre‐Antoine Germain 《Veterinary dermatology》2010,21(3):259-266
Enzootic dermatophytosis in a shelter with approximately 140 cats was treated according to a protocol combining identification, isolation and treatment of subclinical carrier and affected animals in accordance with a three‐area system: healthy animals (no lesions and negative cultures), subclinical carrier animals (no lesions but with positive cultures) and clinically affected animals (lesions and positive cultures). The cats were examined and inspected under a Wood’s lamp and had samples taken for fungal culture every 2 weeks. Thirty‐three per cent of the cats had a positive fungal culture at the start of the study. Clinically affected animals and carriers were treated with a 0.2% enilconazole lotion (Imaverol®) twice a week and given itraconazole (Itrafungol®) 5 mg/kg SID orally every other week. The environment was treated once a day with a 1% bleach solution and once a week with a 0.6% enilconazole (Clinafarm®) solution. Treated animals were considered cured after two consecutive negative fungal cultures. All cats were cured within 56 days. Prophylactic measures against dermatophytosis were implemented for new arrivals consisting of individual quarantine and the systematic taking of fungal cultures. No relapses were observed based on the fungal cultures taken from the animals and the environment over the first 10 months. 相似文献
92.
Amadou M. Bâ Abdala G. Diédhiou Yves Prin Antoine Galiana Robin Duponnois 《Annals of Forest Science》2010,67(3):301-301
93.
Isabelle Pillin Antoine KervoelenAlain Bourmaud Jérémy GoimardNicolas Montrelay Christophe Baley 《Industrial Crops and Products》2011,34(3):1556-1563
Many works deal with the mechanical properties of flax fibers cultivated for textile applications and today used for the reinforcement of polymers. Nevertheless, quantities of oleaginous flax fiber are obtained each year and not promoted. The aim of this work is to study the mechanical properties of single linseed flax fiber as a function of variety, culture year, dew-retting degree and agronomic factors. Five varieties of oleaginous flax have been characterized by tensile tests on elementary fibers and compared to four varieties of textile flax. These tensile experiments have been carried out on with the same equipment, experimental protocol and environmental conditions.The results show that interesting mechanical properties were obtained with the oleaginous variety and are close of those of textile varieties, such as Agatha or Electra. Considering the diameters and specific properties of these oleaginous fibers, we evidenced that they are good candidates for the substitution of glass fibers in composite materials. To increase the development of flax fibers, it is important to have a better control of the spread of their mechanical properties. This point could be observed with the Everest variety cultivated for 4 years and no conclusion could be made.We have evidenced that the retting degree has no influence on the diameters and mechanical properties of the fibers; the same conclusion is obtained with agronomic factors such as seeding rate and plant height. 相似文献
94.
Holger Wernsd?rfer Antoine Colin Jean-Daniel Bontemps Hélène Chevalier Gér?me Pignard Sylvain Caurla Jean-Michel Leban Jean-Christophe Hervé Meriem Fournier 《Annals of Forest Science》2012,69(7):829-844
? Context
Forest resource projections are required as part of an appropriate framework for sustainable forest management. Suitable large-scale projection models are usually based on national forest inventory (NFI) data. However, sound projections are difficult to make for heterogeneous resources as they vary greatly with respect to the factors that are assumed to drive forest dynamics on a large spatial scale, e.g. geographically varying growth conditions (here represented by NFI regions), tree species composition (here broadleaf-dominated, conifer-dominated and broadleaf-conifer mixed stands) and stand structure (here high forest, coppice forest and high-coppice forest mixture).? Question and objective
Our question was how does the variance of forest dynamics parameters (i.e. growth, felling and mortality, and recruitment processes) and that of 20-year forest resource projections partition between these factors (NFI region, tree species composition and stand structure), including their interactions. Our objective was to capitalise on the suitability of an existing multi-strata, diameter class matrix model for the purposes of making projections for the highly heterogeneous French forest resource.? Methods
The model was newly calibrated for the entire territory of metropolitan France based on most recent NFI data, i.e. for years 2006?C2008. The forest resource was divided into strata by crossing the factors NFI region, tree species composition and stand structure. The variance partitioning of the parameters and projections was assessed based on a model sensitivity analysis.? Results
Growth, felling and mortality varied mainly with NFI region and species composition. Recruitment varied mainly with NFI region and stand structure. All three factors caused variations in resource projections, but with unequal intensities. Factor impacts included first order and interaction effects.? Conclusions
We found, by considering both first order and interaction effects, that NFI region, species composition and stand structure are ecologically relevant factors that jointly drive the dynamics of a heterogeneous forest resource. Their impacts, in our study, varied depending on the forest dynamics process under consideration. Recruitment would appear to have a particularly great impact on resource changes over time. 相似文献95.
96.
The black-backed woodpecker (Picoides arcticus) is considered a fire specialist throughout its breeding range. Given its high abundance in recent burns, it has been hypothesized that post-fire forests are source habitats for this species. We conducted a 3-year post-fire study to evaluate the temporal occupancy and reproductive success of black-backed woodpeckers in high-severity burned black spruce forests of central Quebec, Canada. We examined how reproductive success varied temporally and spatially within a burned landscape and investigated the potential source or sink status of this woodpecker population over time. Woodpecker nest density was high in the year after fire but declined significantly over the 3-year period. Based on 106 nests, nest success declined from 84% the first year after fire to 73% and 25%, respectively, for the second and third years after fire. Nest density and reproductive success were higher in areas with high proportions of burned mature forests than in areas dominated by burned young forests. Reproductive success was also higher in proximity to unburned forests. Comparison of annual productivity with a range of survival estimates indicated that these burned forests likely functioned as source habitats for the first 2 years following fire, although this status varied as a function of pre-fire forest age. Our results suggest that post-fire forests may contribute significantly to population levels in fire-prone ecosystems. Forest management practices that reduce the amount of mature and over-mature forests can affect the quality of post-fire habitats important to the black-backed woodpecker and other fire-associated species. 相似文献
97.
98.
Fayeulle Antoine Veignie Etienne Schroll Reiner Munch Jean Charles Rafin Catherine 《Journal of Soils and Sediments》2019,19(7):3056-3067
Journal of Soils and Sediments - Remediation of contaminated soils is of high relevance considering losses of this limited resource in most countries through erosion or through destruction for... 相似文献
99.
Cover cropping is currently increasing in vineyards as it provides solutions to some of the problems encountered in vine growing. However, its development is still hampered in Mediterranean regions because of fears of severe competition for water. Recent studies have shown that soil resources other than water may also be restrictive, and particularly nitrogen. Over a three-year period, the effect of introducing a cover crop was studied with respect to the temporal and spatial changes to nitrogen dynamics in a Mediterranean vineyard. The experiment compared the impact of three different types of soil cover management on nitrogen dynamics, and particularly on soil nitrogen mineralization which is the principal source of inorganic nitrogen in situations with no application of N fertilizers which are frequent in viticulture.This experiment provided evidence that the presence of an intercrop significantly reduced nitrogen accumulation in aerial parts of grapevine during the year due to competition for soil resources. This reduction varied markedly between years and treatments, and was more pronounced during dry years. The competition for nitrogen was direct as intercrop deprived grapevine of soil nitrogen beneath the inter-row and caused grapevine uptake to be higher beneath the row. In deep soils, a grapevine can adapt its root system in order to access deeper water resources, but it then partially abandons the mineralization zone containing most inorganic nitrogen. Competition for nitrogen was less marked with a temporary cover crop than with a permanent one, because of the shorter period of uptake with the former and the time needed for an annual cover crop to develop its root system each year. Intercrop also competed indirectly for nitrogen with grapevine as it took up soil water and made inorganic nitrogen less mobile and accessible to grapevine. Intercrop markedly decreased soil nitrogen mineralization. Although it did not significantly affect organic matter characteristics or soil temperature, it clearly modified the water regime. Indeed, under either temporary or perennial cover crops, the upper soil layers dried more rapidly than when there was only evaporation from bare soil. Consequently, nitrogen mineralization decreased faster with intercropped treatments and halted prematurely during the summer.The earliness of the reduction in nitrogen accumulation in intercropped vineyards also suggested that a lower level of nitrogen transfer to perennial reserves was involved. Indeed, grass cover grows and competes for nitrogen during the autumn which is a favourable period for nitrogen accumulation in wood reserves. Although better water infiltration was observed in the presence of a cover crop (notably in the autumn), the favourable conditions for nitrogen mineralization were propitious for grass cover growth and uptake. Consequently, intercrop reduced grapevine growth of the year but also the potential growth for the next year by decreasing grapevine nitrogen perennial reserves. 相似文献
100.
Tilapia cabrae Boulenger, 1899, a cichlid fish from coastal lowlands of the Republic of Congo (Africa), was examined for gill parasites. Four new species of the Monogenea were found, all belonging to Cichlidogyrus (Ancyrocephalidae): C. berradae sp. n., C. revesati sp. n., C. legendrei sp. n., and C. lemoallei sp. n. A possible relationship between the relative size of haptoral sclerites (i.e., uncinuli compared to gripi) and microhabitat selection in the studied host-parasite model is discussed. 相似文献