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121.
Teodoro Lasanta Estela Nadal‐Romero Paz Errea Jos Arnez 《Land Degradation \u0026amp; Development》2016,27(2):373-386
Mediterranean mountain landscapes have high ecological and cultural values. However, since 1950, a large number of these landscapes have been subject to degradation as a consequence of land abandonment. Some regional administrations have enacted measures that favour the regeneration of pasturelands through scrubland clearing. The aim of this study was to evaluate the consequences of clearing and the regeneration of pasturelands on landscape structure and the recovery of extensive livestock in La Rioja. The results indicate that between 1986 and 2011 an area of 29,659 ha was cleared in the mountains of La Rioja, although 62·6% of this was cleared in the period 2000–2011. In 1956, the landscape was dominated by cultivated fields, but by 2001, much of the agricultural area had been abandoned and replaced by scrubland, natural woods and reforested areas. Furthermore, the landscape was more fragmented in 1956 than in 2001. The landscape structure varied following clearing, with a doubling in the number of patches and an increase in heterogeneity. The consequences of clearing have included an increase in the area of pastureland and the number of large animals. In addition, the number of farms has decreased, but their mean size has increased. Clearing is an appropriate way for spatial reorganization in marginal mountain areas. It does not require excessive investment but favours the reintegration of abandoned fields and an increase in pasturelands. The results of this study contribute to the debate about reclaiming mountain landscapes affected by human activities and subject to intense degradation processes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
122.
This report describes a case of neutrophilic dermatosis in a dog, with a number of clinical and pathological similarities to human pyoderma gangrenosum. A seven-year-old, female German shepherd dog with a history of non-erosive idiopathic polyarthritis was presented with severe facial swelling, bilateral erosivoulcerative lesions on the muzzle and multiple, eroded, dermal-subcutaneous nodules on the cranial trunk. Histopathological examination of skin biopsies revealed a necrotising neutrophilic dermatitis. No infectious agents could be detected using specific stains, immunohistochemistry, serology and bacterial aerobic, anaerobic or fungal cultures. A sterile neutrophilic dermatosis resembling human pyoderma gangrenosum was presumptively diagnosed, and the patient showed an excellent response to treatment with prednisone and ciclosporin. 相似文献
123.
124.
Jiří Svoboda David Fischer Eva Kozubíková-Balcarová Andrea Šťástková Marie Brůčková Antonín Kouba Adam Petrusek 《Journal of fish diseases》2020,43(1):129-138
The crayfish plague pathogen (Aphanomyces astaci) can be transmitted through the digestive system of fish, but its dispersal through mammalian and bird digestive tracts has been considered unlikely, and direct experimental evidence remains scarce. We present a small-scale transmission experiment with European otter and American mink fed with infected crayfish, and experiments testing survival of cultures of five A. astaci strains at temperatures corresponding to those inside mammal and bird bodies. The pathogen was neither isolated from predator excrements nor transmitted to susceptible crayfish exposed to excrements. In agar-based artificial media, it occasionally survived for 15 min at 40.5°C and for 45 min at 37.5°C, but not so when incubated at those temperatures for 45 min and 75 min, respectively. The five tested strains differed in resistance to high temperatures, two (of genotype groups E and D) being more susceptible than other three (of groups A, B and D). Their survival to some extent varied when exposed to the same temperature after several weeks or months, suggesting that some yet-unknown factors may influence A. astaci resistance to temperature stress. Overall, we support the notion that passage through the digestive tract of warm-blooded predators makes A. astaci transmission unlikely. 相似文献
125.
Vlastimil Stejskal Jan Matoušek Markéta Prokešová Peter Podhorec Jiří Křišťan Tomáš Policar Tatyana Gebauer 《Journal of fish diseases》2020,43(2):253-262
We evaluated the relationship of stocking density to survival, growth performance and fin condition of European perch Perca fluviatilis with hand feeding and self-feeders. Hand-fed perch (body weight 19.1 ± 5.1 g and total length 107 ± 9 mm) were reared at 0.5, 1.0, 1.5 and 2.0 fish/L. Self-feeding perch (body weight 25.4 ± 3.9 g and total length 128 ± 7 mm) were reared at stocking densities of 0.6, 1.0 and 1.4 fish/L. Pond-reared perch served as a comparison group for fin damage assessment. We found no differences in survival rate among stocking densities with either feeding method. Hand-fed fish displayed the highest weight gain and SGR at stocking density of 0.5 fish/L. The self-feeding fish showed a non-linear association of weight gain with stocking density with the highest growth at 1.0 fish/L. Fin length was noticeably greater in pond-reared fish compared with RAS-reared fish regardless of feeding method. In both experiments, fin length relative to standard length showed a negative relationship with stocking density, with pectoral fins showing the greatest effect. Fin condition deteriorated with increasing stocking density, and growth was highest at 0.5 and 1.0 fish/L in hand-fed and self-feeding fish, respectively. 相似文献
126.
Tardigrade communities are affected by micro and macro-environmental conditions but only micro-environmental variables, and
altitudinal gradients have been studied. We review previous reports of altitudinal effects and evaluate the influence by interacting
macro- (climate, soils, biome, and others) and micro-environmental (vegetation, moss and leaf litter) factors on tardigrade
assemblages at the Sierra de Guadarrama mountain range (Iberian Central System Mountains, Spain). Terrestrial tardigrade assemblages
were sampled using standard cores to collect leaf litter and mosses growing on rocks. General Linear Models were used to examine
relationships between Tardigrada species richness and abundance, and macro- and micro-environmental variables (altitude, habitat
characteristics, local habitat structure and dominant leaf litter type, and two bioclimatic classifications). Variation partitioning
techniques were used to separate the effects of altitude and habitat variation, and to quantify the independent influences
of climate and soil, vegetation structure and dominant type of leaf litter. Altitude shows a unimodal relationship with tardigrade
species richness, although its effect independent of habitat variation is negligible. The best predictors for species richness
were bioclimatic classifications. Separate and combined effects of macro-environmental gradients (soil and climate), vegetation
structure and leaf litter type are important determinants of richness. A model including both macro- and micro-environmental
variables explained nearly 60% of tardigrade species richness in micro-scale plots. Abundance was significantly related only
to soil composition and leaf litter type. Tardigrade abundance was not explained by macro-environmental gradients analysed
here, despite a significant correlation between abundance and richness. 相似文献
127.
The in vitro activity of some isolated hydroxyanthracenones belonging to the genus Karwinskia against four bacteria, six filamentous fungi and four yeast are reported. These hydroxyanthracenones were found to possess antimicrobial activity, particularly against Streptococcus pyogenes, Candida albicans, C. boidinii, C. glabrata and Cryptococcus neoformans; minimal inhibitory concentrations range between 16 and 2 microg/ml. 相似文献
128.
129.
Jorge Alfonso Murillo-González Belen Notario Estela Maldonado Elena Martinez-Sanz M. Carmen Barrio Manuel Herrera 《Anatomia, histologia, embryologia》2021,50(1):84-92
Sheep are recognized as useful species for translational neurodegeneration research, in particular for the study of Huntington disease. There is a lack of information regarding the detailed anatomy and connections of the basal ganglia of sheep, in normal myeloarchitectonics and in tract-tracing studies. In this work, the organization of the corticostriatal projections at the level of the putamen and globus pallidus (GP) are explored. For the first time, the myeloarchitectonic pattern of connections between the internal (IC) and the external (EC) capsules with the GP have been investigated in the sheep. Formaldehyde-fixed blocks of the striatum were treated with a metallic stain containing potassium dichromate and visualized using micro-CT (µ-CT). The trivalent chromium (Cr3+), attached to myelin phospholipids, imparts a differential contrast to the grey and white matter compartments, which allows the visualization of myelinated fascicles in µ-CT images. The fascicles were classified according to their topographical location in dorsal supreme fascicles (X, Y, apex) arising from the IC and EC; pre-commissurally, basal fascicles connecting the ventral part of the EC with the lateral zone of the ventral pallidum (VP) and, post-commissurally, superior (Z1), middle (Z2) and lower (Z3) fascicles, connecting at different levels the EC with the GP. The results suggest that the presumptive cortical efferent and afferent fibres to the pallidum could be organized according to a dorsal to ventrolateral topography in the sheep, similar to that seen in other mammals. The proposed methodology has the potential to delineate the myeloarchitectonic patterns of nervous systems and tracts. 相似文献
130.