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41.
Malassezia nana (M. nana) is a lipid-dependent yeast that has been isolated from cats and cows. Some sequence variability has been observed in the large subunit (LSU) and internal transcribed spacer (ITS) regions between strains isolated from cats and cows though these regions in M. nana isolates from cats alone have proven to be relatively conserved. In the present study, microsatellite PCR fingerprinting and β-tubulin gene sequence analysis were carried out on M. nana isolates from cats to investigate the genetic diversity of this species. Although a relatively small number of isolates were available, the similarity in the sequences of the β-tubulin and the microsatellite profiles indicate that a particular M. nana genotype colonizes cats. Moreover, all isolates obtained from animals with otitis externa had the same microsatellite fingerprinting pattern. Further studies of a wider population of M. nana isolates from other hosts and status disease are needed to establish that M. nana is a genetically homogeneous species. This is the first report of the characterization of the β-tubulin gene in Malassezia spp.  相似文献   
42.
Objective— To compare the biomechanical properties of cervical arthroplasty to a ventral slot procedure and pin‐polymethylmethacrylate (pin‐PMMA) fixation. Sample Population— Fresh cadaveric cervical (C2–T1) spines from 6 large dogs. Methods— Four spinal conditions were studied in each spinal specimen: intact, disk arthroplasty, ventral slot, and fixation with smooth pin‐PMMA at C5–C6 intervertebral space. Axial compression, torsion, flexion–extension, and lateral bending moments were sequentially tested on each specimen for the 4 spinal conditions. Data from the C3–C4, C4–C5, C5–C6, and C6–C7 vertebral motion units (VMUs) were compared among treatments. Results— In axial compression and torsion, the ventral slot procedure allowed significantly less motion than intact, pin‐PMMA, and arthroplasty groups at C5–C6. In lateral bending and flexion–extension, pin‐PMMA had the least motion of C5–C6, followed by the arthroplasty group, intact spine, and ventral slot, all of which were significantly different from each other. Overall, the artificial disk was better able to mimic the behavior of the intact specimens compared with the ventral slot and pin‐PMMA, producing similar displacements in axial compression and rotation in torsion, but more limited motion than intact in flexion–extension and in lateral bending. Conclusion— Cervical spine specimens with an implanted prosthesis have biomechanical behaviors more similar to an intact spine compared with spinal specimens with ventral slot and pin‐PMMA procedures. Cervical arthroplasty may then preserve some of the motion in the affected area after neural decompression while providing distraction. Clinical Relevance— Cervical arthroplasty should be further investigated in vivo to determine if it is a viable alternative to the ventral slot or pin‐PMMA procedures for surgical treatment of cervical diseases in dogs and in particular for treatment of disk‐associated caudal cervical spondylomyelopathy.  相似文献   
43.
44.
The seeds of the main Italian carob varieties, Latinissima and Tantillo, and those of two selected accessions of Latinissima were evaluated in terms of yield, rheological properties, and sugar composition of the endosperm (LBG). The separation of the seed components in Latinissima and its seedlings yielded meanly 52.2% gum, 17.4% germ, and 30.5% tegument, whereas Tantillo furnished a lower gum yield (38.5%) and a higher yield of tegument (45.8%). The viscosity of 1% LBG aqueous solutions was measured at different shear rates (3-60 rpm), pH values (3.0-6.0), and temperatures (10-60 degrees C). The best results were shown by Latinissima, whereas Tantillo provided always the poorest thickening capacity. The content of free simple sugars and sucrose in the raw flours, the total monosaccharide residues after acidic hydrolysis, the mannose/galactose ratio, and the distribution of polysaccharides by size exclusion chromatography accounted for the observed viscosities. The seeds of Latinissima showed the highest technological potential.  相似文献   
45.
Genetic Resources and Crop Evolution - The genus Brachypodium is generally considered taxonomically difficult because of the high levels of phenotypic variation and frequent...  相似文献   
46.
Essential oil from flowers (FL) and vegetative parts (VP) of Achillea ligustica (Asteraceae), naturalized after cultivation in central Italy, was investigated by GC–FID and GC–MS. The most abundant components were linalool, viridiflorol, β-pinene, 1,8-cineole and terpinen-4-ol. The antioxidant assays (DPPH and ABTS radical scavenging assays, and β-carotene bleaching test) demonstrated a moderate activity of essential oils. The antimicrobial activity was evaluated by the broth micro-dilution method on 6 microbial strains and showed to be quite strong against the cariogenic Gram-positive Streptococcus mutans, suggesting that this essential oil could be a valid candidate for anti-cariogenic formulations. Moderate cytotoxic activity was observed in assays on four tumour cell lines by MTT assay.  相似文献   
47.

Purpose

Phytostabilization with native plant species might represent an economically more realistic and cost-effective option than excavation, soil washing, and sludge disposal for rehabilitation of degraded and polluted industrial areas. This work was done to assess the changes induced by native plant revegetation in the chemical properties and mobility-bioavailability of Pb and Zn pollutants of soil and post-washing sludges from an Italian brownfield site of national interest.

Materials and methods

A 5-year native plant revegetation of polluted soil and relative post-washing sludges from a steel plant was achieved in situ and ex situ in pot and in the presence and absence of peat as organic amendment. During the experiment, the vegetation growth was monitored (Adamo et al. In Int J Environ Sci Technol 12(6):1811–1824, 2015). Before and after plant growth, the substrates were studied for pH, organic carbon, and carbonate contents. Lead, Zn, and other metal mobility and leachability were investigated by water extraction. The metal bioavailability was estimated by diethylenetriaminepentaacetic acid (DTPA) extraction at pH 7.3. Sequential extractions (BCR procedure) were used to fractionate Pb and Zn in soil main geochemical forms. Plant ability to uptake metals was evaluated on the three most representative species: Bituminaria bituminosa, Daucus carota, and Dactylis glomerata.

Results and discussion

After 5 years of revegetation with native plants, the substrate pH and organic carbon content were respectively decreased and increased by plant growth, with changes masked by peat treatments. Although metal pollutants in both substrates were characterized by low water solubility and DTPA availability, after plant growth, an increase of rhizospheric Zn, Cu, Fe, and Mn solubility in H2O was detected. According to metal speciation, Pb and Zn were largely occluded in easily reducible manganese/iron oxides and trapped in the mineral structure of silicates, with no visible changes of distribution after plants. Water extraction always underestimated plant uptake, whereas DTPA and sequential extractions better predicted Pb and Zn uptake.

Conclusions

Despite the original extremely low mobility and bioavailability of metal pollutants in both soil and post-washing sludges, the acidification and increase of organic carbon content induced by peat amendments and plant growth enhance the solubility in water of metal-containing compounds. Therefore, attention must be paid to these effects in the long period. A continuous monitoring of the changes of pollutant mobility-bioavailability induced by native plant revegetation of brownfields is crucial to prevent risks to the surrounding environment and human health.
  相似文献   
48.
Savi's pine vole (Microtus savii) is a rodent species of the Cricetidae family, inhabiting southern European agroecosystems. It is considered to be the main cause of rodent‐attributed damage in Italy. To achieve an effective management, detailed knowledge of this species is needed. However, the available information about this species is fragmentary and incomplete. In this paper, the existing knowledge of Savi's pine vole taxonomy, reproduction, population dynamics, habitat and food preferences is reviewed in order to organise available information and identify priority areas of future research. Some of the changes in farming practices that have occurred in recent decades may have increased the impact of Savi's pine vole populations in crop fields. To manage this pest species effectively, an integrated strategy is recommended (involving habitat management, trapping and, when appropriate, the use of rodenticides). The apparent lack of cyclical population outbreaks and the relatively small litter size and long gestation and interpartum period of this species suggest that it could be more manageable than other vole species, while its strict herbivorous diet, stable population size in open habitats and wide distribution seem to indicate it as an ideal model species for risk assessment studies. © 2015 Society of Chemical Industry  相似文献   
49.

Background

Noise (errors) in scientific data is endemic and may have a detrimental effect on statistical analyses and experimental results. The effects of noisy data have been assessed in genome-wide association studies for case-control experiments in human medicine. Little is known, however, on the impact of noisy data on genomic predictions, a widely used statistical application in plant and animal breeding.

Results

In this study, the sensitivity to noise in the data of five classification methods (K-nearest neighbours—KNN, random forest—RF, ridge logistic regression—LR, and support vector machines with linear or radial basis function kernels) was investigated. A sugar beet population of 123 plants phenotyped for a binary trait and genotyped for 192 SNP (single nucleotide polymorphism) markers was used. Labels (0/1 phenotype) were randomly sampled to generate noise. From the base scenario without errors in the labels, increasing proportions of noisy labels—up to 50 %—were generated and introduced in the data.

Conclusions

Local classification methods—KNN and RF—showed higher tolerance to noisy labels compared to methods that leverage global data properties—LR and the two SVM models. In particular, KNN outperformed all other classifiers with AUC (area under the ROC curve) higher than 0.95 up to 20 % noisy labels. The runner-up method, RF, had an AUC of 0.941 with 20 % noise.
  相似文献   
50.
Tropical Animal Health and Production - Small ruminant lentiviruses (SRLVs) are a heterogeneous group of viruses of sheep, goat, and wild ruminants responsible of lifelong persistent infection...  相似文献   
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