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1.
  1. A large‐scale assessment of the summertime suitable habitat for Delphinus delphis (short‐beaked common dolphin) and Tursiops truncatus (common bottlenose dolphin) in Greek Seas (Eastern Mediterranean) was conducted using data from dedicated and opportunistic cetacean surveys and published data records.
  2. Using a presence/absence approach, generalized additive models were applied to define a suite of environmental, bathymetric and biotic factors that best describe common and bottlenose dolphin spatial distribution, during early (May, June, July) and late (August, September) summer.
  3. A geographic information system (GIS) was used to integrate sightings data with environmental characteristics, distance from the coast and sardine probability of presence. These variables were considered as good proxies for defining species‐suitable habitat within the study area's coastal environment.
  4. The final selected models were used to produce annual probability maps of the presence of the species in the entire Greek Seas, as a measure of habitat suitability. Based on the mean probability and standard deviation maps for the study period GIS techniques were subsequently used to determine the persistent (areas with high mean and low variation) and occasional (high mean and high variation) habitat of each species.
  5. Results showed that there was a high probability of common dolphin presence in areas with a high probability of sardine presence. For bottlenose dolphin, higher probability of the presence of species occurred in areas closer to the shore, with a high probability of sardine presence and with high concentrations of chlorophyll‐a.
  6. In both seasons, the North Aegean Sea and the Inner Ionian Sea Archipelago were indicated as the most suitable areas for common dolphin distribution. Persistent habitat areas of the bottlenose dolphin included enclosed seas, continental shelf waters, and waters surrounding islands. The indicated suitable areas are discussed along with deficiencies of the models and future implications for conservation.
Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
2.
A novel spectrophotometric method for the determination of capsaicinoids in habanero pepper extracts is described that does not require prior analyte separation. The method uses partial-least-squares (PLS-1) multivariate regression modeling techniques in conjunction with ordinary UV absorption spectral data obtained on alcoholic extracts of habanero peppers (Capsicum chinese). The PLS-1 regression models were developed by correlating the known total concentration of the two major capsaicinoids (capsaicin and dihydrocapsaicin) in the extracts as determined by high-performance liquid chromatography with the spectral data. The regression models were subsequently validated with laboratory-prepared test sets. The validation studies revealed that the root-mean-square error of prediction varied from 4 to 8 ppm, based on the results obtained from models prepared from nine test sets. Once a regression model has been developed and validated, analyses of the extracts can be accomplished rapidly by ordinary spectrophotometric procedures without any prior separation steps.  相似文献   
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OBJECTIVE: To determine clinical signs and clinicopathologic abnormalities in dogs with naturally occurring clinical spirocercosis. DESIGN: Retrospective case series. ANIMALS: 39 dogs with spirocercosis. PROCEDURES: Medical records were reviewed, and information on signalment, residence (rural vs urban), owner complaints, physical examination findings, clinicopathologic abnormalities, radiographic and endoscopic findings, and concurrent systemic diseases was recorded. RESULTS: Hellenic hounds and mixed-breed dogs were overrepresented, compared with a group of 117 control dogs without spirocercosis that were examined because of gastrointestinal tract disease, and mean body weight of dogs with spirocercosis was significantly higher than mean body weight of control dogs. Odynophagia (34 [87%]), regurgitation (24 [62%]), and excessive salivation (14 [36%]) were the most common clinical findings. The most common radiographic abnormalities were a mass in the caudodorsal aspect of the mediastinum (15/35 [43%]) and spondylitis of the caudal thoracic vertebrae (10 [29%]). Parasitic nodules were seen during esophagoscopy in all 39 dogs. Normocytic, normochromic, nonregenerative anemia; neutrophilic leukocytosis; hyperproteinemia; and high alkaline phosphatase activity were significantly more common in dogs with spirocercosis than in a control group of 56 healthy dogs. Concurrent systemic diseases, mainly leishmaniosis, dirofilariosis, and monocytic ehrlichiosis, were documented in 14 (36%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that clinical spirocercosis occurs more often in young-adult, large-breed dogs. Nonregenerative anemia, neutrophilic leukocytosis, hyperproteinemia, and high alkaline phosphatase activity may be useful clinicopathologic indicators of this disease.  相似文献   
4.
Intervertebral disc (IVD) degeneration is common in dogs and can give rise to a number of diseases, such as IVD herniation, cervical spondylomyelopathy, and degenerative lumbosacral stenosis. Although there have been many reports and reviews on the clinical aspects of canine IVD disease, few reports have discussed and reviewed the process of IVD degeneration. In this first part of a two-part review, the anatomy, physiology, histopathology, and biochemical and biomechanical characteristics of the healthy and degenerated IVD are described. In Part 2, the aspects of IVD degeneration in chondrodystrophic and non-chondrodystrophic dog breeds are discussed in depth.  相似文献   
5.
Due to decades of loss of grassland diversity across Europe, there is a need to identify factors affecting species composition and diversity in managed meadows. The aim of the current study was to assess how ecological, landscape and management factors may affect plant species composition, biodiversity and forage value in Alpine hay meadows. Species composition, Shannon index and forage value were obtained from phytosociological relevés. Twenty explanatory variables were selected from a set of ecological, landscape and management factors. Their effects on plant species composition, Shannon index and forage value were analysed by applying the variation partitioning approach. Plant species composition was related to sixteen factors, explaining 35·6% of the variability. Shannon index and forage value were related to eleven factors, explaining 47·8 and 40·8% of their total variation respectively. Ecological factors were the main set explaining species composition and diversity, whereas none of the three individual groups of factors (ecological, landscape, management) significantly explained variability within forage value. Overall, the effects of the three groups of factors accounted for 70% of the total variability in plant species composition, but less than half that of Shannon index and of forage value.  相似文献   
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A collection was carried out in the Italian Alps to gather local genetic resources and acquire information on the ecological adaptation of supina bluegrass (Poa supina Schrad.), a cool‐season grass native to the Alpine region in Europe. It has potential for pastures and a growing interest for turfs, owing to excellent traffic, shade and cold tolerance. Available germplasm for research and breeding is scant, and extensive collections are needed to enable further development of adapted materials. Alpine germplasm has already proved valuable for breeding at lower altitude in pioneering selection work carried out in Germany. Extensive exploration throughout different environments, mostly above 1600 m elevation, yielded fifty‐five novel populations. Collections largely occurred in environments exposed to heavy disturbance by livestock, but it was also frequently found on very poor substrates along mountain paths and dirt roads, or around buildings. Some populations were present locally in shaded environments. Preliminary ex‐situ observations indicated likely among‐population variation to occur for important traits of breeding relevance such as disease and drought tolerance. Genetic variation for adaptive traits, although unproven, is hypothesized given the diversified habitats where the species was collected across the Italian Alps.  相似文献   
9.
Large-scale correlates of alien plant invasion in Catalonia (NE of Spain)   总被引:1,自引:0,他引:1  
Identification of the main correlates of the invasion process is a fundamental step in alien species management at the regional scale. This paper explores the main climatic, territorial, and anthropic correlates of alien plant species richness and percentage in Catalonia (NE of Spain), by means of GIS techniques. We used floristic data collected in FLORACAT per UTM 10 km × 10 km to set up the number and the percentage of alien species. The association of these variables with climate, topography, landscape, human settlement, and geographic position was explored by means of stepwise regression models applied on the axes obtained from principal component analysis. The significance of the resulting correlates was tested using the modified t test of Dutilleul to remove the effects of spatial autocorrelation. PCA reduced the 22 variables to 12 principal components (PC) that explained 90% of the cumulative variance. Regression models were highly significant and captured a high proportion of total variance (adjusted r2 = 0.70 for alien species richness and r2 = 0.56 for alien species percentage). Both alien species richness and percentage were mainly correlated to PC summarising variables concerning climate, habitat and landscape heterogeneity, and potential anthropogenic disturbance. However, while these PC exhibited similar weights on alien species richness, species percentage was mainly determined by climate. Implications for conservation are discussed considering a future scenario of climate warming and increasing land use change in Mediterranean areas.  相似文献   
10.
The squid pen (gladius) from the Loligo vulgaris was used for preparation of β-chitin materials characterized by different chemical, micro- and nano-structural properties that preserved, almost completely the macrostructural and the mechanical ones. The β-chitin materials obtained by alkaline treatment showed porosity, wettability and swelling that are a function of the duration of the treatment. Microscopic, spectroscopic and synchrotron X-ray diffraction techniques showed that the chemical environment of the N-acetyl groups of the β-chitin chains changes after the thermal alkaline treatment. As a consequence, the crystalline packing of the β-chitin is modified, due to the intercalation of water molecules between β-chitin sheets. Potential applications of these β-chitin materials range from the nanotechnology to the regenerative medicine. The use of gladii, which are waste products of the fishing industry, has also important environmental implications.  相似文献   
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