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81.
A 3‐year‐old female mixed‐breed dog was referred with a 2‐day history of serious dyspnea, coughing, lethargy, anorexia, and a low‐grade right anterior lameness. At presentation, the dog had an increased respiratory rate, dull heart and lung sounds, and cyanotic mucous membranes. It was hyperthermic and slightly dehydrated. Laboratory findings showed mild neutrophilia with a left shift, while serum biochemistry variables were in the normal range. However, urinalysis revealed mild proteinuria and rare erythrocytes and leukocytes on sediment examination. Thoracic radiographs showed a diffuse mixed interstitial and alveolar pattern with an air bronchogram, while appendicular radiographs showed a right humeral interrupted brush‐like periosteal reaction. Thoracic ultrasonography revealed mediastinal lymph node enlargement. Cytology from a fine‐needle aspirate of mediastinal lymph nodes revealed a pyogranulomatous lymphadenitis with numerous fungal hyphae. Culture on Sabouraud dextrose agar isolated dark fungal colonies with microscopic features consistent with Cladosporium spp. Sequencing of the internal transcribed spacer region identified the fungus as a species of the Cladosporium cladosporioides‐complex.  相似文献   
82.
Europe’s woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.  相似文献   
83.
A size‐age modelling technique is presented for assessing the vital rates, stock and recruitment of eel populations in semi‐closed lagoons with fully monitored migration of silver eels. Data for yellow and silver European eels (Anguilla anguilla L.) were obtained in 2011 from the Comacchio lagoon (Italy). The analysis was performed in three steps: (i) correction of yellow eel data, which are affected by the fyke nets selectivity during samplings, (ii) estimation of survival curve, stock, recruitment and metamorphosis rates of the population (calibration using data from 2011) and (iii) validation of the model using the observed amount of silver eel migrating population of the next year. A bootstrap procedure was used to assess the level of uncertainty for each parameter using the 95% intervals of the highest posterior density distribution HPDD (Bayesian approach). The measured abundance of silver eels was 0.56 ind·ha?1, while the yellow eel abundance and recruitment were estimated by the model for 2011 at 8.77 ind·ha?1 and 5.99 ind. ha?1 respectively. The model performance during validation was satisfactory as the observed total mass of migrating population of 2012 (3777 kg) was inside the 95% HPDD intervals (3197–3839 kg) of model's predictions. The estimated stocks and recruitment were at least ten times lower from the respective estimations of previous studies of 1989 highlighting the crucial conditions of the population. The proposed modelling approach can provide significant information about eel population conditions, facilitating the evaluation of a range of management options in the context of eel conservation plans.  相似文献   
84.
85.
The aims of this work were to re-evaluate the moments of resistance (MoRs) of the vertebral column proposed by Slijper (1946) in the dog and to study the relationship between the MoRs and the frequency distribution of vertebral traumas in the same species. The spine (C2-L7) of four dogs was measured to obtain MoRs and subsequently scanned with a dual-energy X-ray absorptiometer (DXA). These findings were then analysed retrospectively the frequency distribution of canine vertebral fractures and luxations, diagnosed radiographically at a referral practice. The highest percentage of vertebral injuries affected the T9-L7 tract. This study confirmed that this segment was characterized by a rising trend of the MoR curves and presumably bore the major bending forces. The significant correlation between T9-L1 MoRs and DXA values supports the Slijper’s hypothesis suggesting the posterior thoracic region as the weakest segment of the body-axis.  相似文献   
86.
Landslides are considered a form of physical soil degradation and are concentrated, especially in southern European countries, on inland and marginal rural areas. Low‐density, economically disadvantaged and poorly accessible areas are assumed to share a high landslide occurrence probability. However, an empirical verification of this assumption is still lacking for Mediterranean countries. This study investigates the spatial relation between a composite index of landslide risk and more than 100 indicators at the municipal level in Italy – a country with high landslide risk – exploring multiple territorial dimensions (population dynamics and settlements, job market and human capital, economic specialization and competitiveness, quality of life, agriculture and rural development, territory and environment). We combine nonparametric correlation, principal component analysis and hierarchical clustering, to profile municipalities according to their levels of landslide risk. The high landslide risk in certain areas of Italy is related to specific socio‐economic attributes (depopulation, ageing, tourism specialization, low density of economic activities, modest participation to the job market and crime intensity) and agro‐environmental features (low‐intensity cropping systems, natural landscapes and water resource availability).  相似文献   
87.
Exposure to UV-A radiation is known to induce discrete lesions in DNA and the generation of free radicals that lead to a wide array of skin diseases. Strawberry (Fragaria × ananassa) contains several polyphenols with strong antioxidant and anti-inflammatory activities. Because the major representative components of strawberry are anthocyanins, these may significantly contribute to its properties. To test this hypothesis, methanolic extracts from the Sveva cultivar were analyzed for anthocyanin content and for their ability to protect human dermal fibroblasts against UV-A radiation, as assayed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenytetrazolium bromide and Comet assays. Five anthocyanin pigments were identified using high-performance liquid chromatography-diode array detection-electrospray ionization/mass spectrometry. Moreover, the strawberry extract showed a photoprotective activity in fibroblasts exposed to UV-A radiation, increasing cellular viability, and diminishing DNA damage, as compared to control cells. Overall, our data show that strawberry contains compounds that confer photoprotective activity in human cell lines and may protect skin against the adverse effects of UV-A radiation.  相似文献   
88.
The aim of this work was to evaluate the susceptibility to flavescence dorée (FD) of 12 Vitis vinifera cultivars grown in Piedmont, and representative of the wine-making tradition of this area. The experiments were conducted under controlled conditions to ensure constant infection pressure. Test plants were ex vitro potted vines, singly inoculated with four Scaphoideus titanus infected by FD-C phytoplasma (FDp), under greenhouse conditions. Vines were tested for FDp at 5 and 8 weeks postinoculation (wpi) and the phytoplasma load was measured in leaves and roots at 8 wpi. Within the 14 V. vinifera accessions (belonging to 12 cultivars), three susceptibility clusters were identified. Cultivars within the low susceptibility group showed low phytoplasma loads and low percentages of infected plants, suggesting a tolerant behaviour. To confirm these results, four Vitis cultivars, representing extremes of FD susceptibility from low to high, were grafted onto Kober 5BB rootstocks and inoculated with laboratory-infected S. titanus, under semi-field conditions. The transmission experiments onto grafted cuttings confirmed that susceptibility to the disease depends on the scion genotype. The data indicated that none of the tested V. vinifera genotypes are resistant to FD, although some cultivars with low susceptibility are available, and can be explored for identifying genetic traits involved in disease tolerance/resistance. Moreover, ranking Vitis genotypes for their susceptibility to FD is in itself a valuable tool to support vine growers in their decision management, by helping them to choose the most appropriate varieties according to their specific FD epidemiological contexts.  相似文献   
89.
A total of 25 ornamental plant species representing 10 families were inoculated using three genotypes, each representing one of the genetic lineages NA1, NA2, and EU1 of the pathogen Phytophthora ramorum. Leaves were inoculated using suspensions with two zoospore concentrations and exposure at three temperatures, while stems were inoculated using agar plugs colonized by mycelia. Susceptibility was determined by measuring either the success of pathogen reisolation or lesion length caused by the pathogen. Infectivity was determined by counting sporangia in washes of inoculated leaves or stems. Results from all three pathogen genotypes combined were used to rank each of the 25 plant species for susceptibility and infectivity, while pooled results per genotype from all 25 hosts combined were employed for a preliminary comparison of pathogenicity and infectivity among genotypes. Statistical analyses showed that leaf results were affected by the concentration of zoospores, temperature, plant host, pathogen genotype, and by the interaction between host and pathogen genotype. Stem results were mostly affected by host and by the interaction between host and pathogen genotype. Hosts ranked differently when looking at the various parameters, and differences in rankings were also significant when comparing stem and leaf results. Differences were identified among the 25 hosts and the three pathogen genotypes for all parameters: results can be used for decision-making regarding regulations or selection of plants to be grown where infestations by P. ramorum are an issue.  相似文献   
90.
We estimated water-use efficiency and potential photosynthetic assimilation of Holm oak(Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in two Mediterranean coppice forests. We used standard techniques for quantifying gas exchange and carbon isotopes in leaves and analyzed total chlorophyll, carotenoids and nitrogen in leaves collected from Mediterranean forests managed under the coppice system. We postulated that responses to drought of coppiced trees would lead to differential responses in physiological traits and that these traits could be used by foresters to adapt to predicted warming and drying in the Mediterranean area. We observed physiological responses of the coppiced trees that suggested acclimation in photosynthetic potential and water-use efficiency:(1) a significant reduction in stomatal conductance(p0.01) wasrecorded as the drought increased at the SW site;(2) foliar δ13C increased as drought increased at the SW site(p0.01);(3) variations in levels of carotenoids and foliar nitrogen, and differences in foliar morphology were recorded, and were tentatively attributed to variation in photosynthetic assimilation between sites. These findings increase knowledge of the capacity for acclimation of managed forests in the Mediterranean region of Europe.  相似文献   
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