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171.
Andrea Coppi 《Biological conservation》2008,141(8):2000-2011
Although several plants endemic to Corsica and Sardinia are included in various redlists, no attempts have been made to analyse their genetic diversity with molecular techniques. Genus Anchusa occurs with seven taxa in either mountain or coastal habitats of the two islands, but the very restricted range and low population size pose these endemisms in a very precarious conservation status. Highly variable markers (AFLP) were therefore used to analyse the patterns and levels of genetic diversity in a sample of 11 populations from the entire range of the group.Results indicate the separation between a mountain genic pool including Anchusa formosa, Anchusa capellii and Anchusa montelinasana, and four groups of coastal accessions. In spite of small size, mountain taxa show low interpopulation differentiation (Fst = 0.02) and relatively high intrapopulation genetic variation (0.365), while coastal accessions showed on average a stronger differentiation (mean Fst = 0.20) and a lower diversity (0.281), possibly due to higher rates of inbreeding. The particularly low levels of variation found in A. sardoa, A. littorea and A. crispa ssp. maritima from the Coghinas bay are likely due to a historical decrease of populations and to bottleneck events caused by loss of habitat and natural stochastic factors on sand dune ecosystems. While habitat maintenance and regulation of grazing by domestic herbivores should be sufficient to ensure the persistence of the mountain endemics, additional actions of in situ and ex situ conservation are needed for the critically endangered coastal species A. sardoa and A. littorea. A. crispa showed a relatively high variation, especially on Corsica. No correlation between population size and genetic variation was found in the latter species, highlighting the importance of the small patches for its conservation. Also, the genetic separation between subspecies crispa and maritima stresses the need of keeping them distinct in redlists and conservation actions on Sardinia. 相似文献
172.
Masino F Montevecchi G Arfelli G Antonelli A 《Journal of agricultural and food chemistry》2008,56(20):9495-9501
In this study, two different doses of commercial beta-glucanase enzyme preparation were tested to verify their effect on wines aged on lees. These wines were compared with two samples with no enzymatic treatment. The former was aged on lees (control), and the latter was readily filtered off from the yeast cell biomass (standard). Analysis of variance (one-way ANOVA), the Tukey test, and principal component analysis (PCA) were applied to all of the samples, which were analyzed for aroma composition, along with galacturonic acid, total acidity, pH, and color. Results showed a large number of statistically significant differences among samples. In general, wines treated with beta-glucanase were characterized by higher concentration of many volatile compounds. The presence of lees and even more the exogenous enzymatic action enhanced almost all volatile compounds. Besides the high presence of ethyl esters, it is worth mentioning the behavior of hexanol and trans-3-hexenol, which are strongly enhanced by the presence of lees and by enzymatic treatments. 相似文献
173.
Cocchi M Consonni R Durante C Grandi M Manzini S Marchetti A Sighinolfi S 《Journal of agricultural and food chemistry》2008,56(15):6397-6407
Cooked must is the starting raw material in Aceto Balsamico Tradizionale di Modena (ABTM) production, and the cooking process is a crucial step to ensure quality and safety standards. In particular, the furfural content has to be strictly monitored. In this study, we followed, directly at the production plant, nine cooking processes, differing for grape type and process conditions in order to monitor the actual variability in cooked must reduction. 5-Hydroxymethylfurfural (5-HMF) and furfural contents were determined by high performance liquid chromatography (HPLC) technique and glucose, fructose, and tartaric and malic acids by gas chromatography (GC) technique. Furthermore, some bulk properties, such as the water content, refractive index, density, and total acidity, were also measured. The obtained results show that the product undergoes, in the worse operating conditions, remarkable degradation, leading to extremely high levels of furfurals (5-HMF and furfural), corresponding to a water content lower than 40%. On the basis of these results, a first draft of an optimal heating protocol may be suggested in order to guarantee the safety and quality of the final product. 相似文献
174.
Particulate phosphorus (P) can be transported via soil erosion in overland flow to waters, where it provides a long-term source of P for aquatic biota, and can accelerate freshwater eutrophication. Hence, knowledge of P sources is important for good environmental management. However, data on P, and related Fe, losses from various structures of a post-mining landscape are lacking. A year-long monitoring, and ten short rainfall simulations on plot scale, at ridges and rills and a combination of them, revealed high erosion from bare lignite mining dumps at Schlabendorf-North, Lusatia, Germany. The mean annual soil erosion rate from the year-long monitoring site was 18 × 106 kg km− 2 yr− 1, corresponding to 0.034 g m− 2 min− 1. The erosion rates were lowest at rill plots (1.9–4.4 g m− 2 min− 1), intermediate at ridge plots (14.3–37.1 g m− 2 min− 1), and highest at a combined rill and ridge plot (48.7–63.4 g m− 2 min− 1). These differences in extent were due to small scale differences in morphology and extreme water repellency. The hydrophobicity leads to very low infiltration, thus generating surface runoff even at low rainfall intensities. Loss rates of P and Fe, as deduced from the year-long erosion rate, were 470–650 kg km− 2 yr− 1, and 37.9 × 103–71 × 103 kg km− 2 yr− 1 respectively. However, these P inputs from lignite mining dump erosion, consisting of P-poor (17–90 μg g− 1) tertiary spoil materials, into aborning mining lakes, are negligible since they are accompanied by high Fe inputs, which favour an efficient P co-precipitation in the water column. 相似文献
175.
van Asten AJ Allaart JG Meeles AD Gloudemans PW Houwers DJ Gröne A 《Veterinary microbiology》2008,127(3-4):412-416
Clostridium perfringens which is a causative agent of several diseases in animals and humans is capable of producing a variety of toxins. Isolates are typed into five types on the basis of the presence of one or more of the four major toxins genes, i.e. cpa, cpb, etx, and iap. A decade ago another toxin termed beta2 (beta2) and its gene (cpb2) were identified. Two alleles of cpb2 are known and a possible link between differences in gene expression and allelic variation has been reported. A correlation between the level of expression and the origin of the isolates has also been suggested. The demonstration and typing of the cpb2 gene in the genome of isolates can be seen as a vital part of research on the role of the beta2 toxin in the pathogenesis of disease. This study describes a PCR with a single primer set which in contrast to published primer sets recognizes both alleles. Subsequent restriction enzyme analysis of the PCR product enables typing of the alleles. Applying this protocol on a total of 102 isolates, a sub-variant was found which occurred only in C. perfringens isolates from pigs and appeared to be the predominant variant found in C. perfringens isolates from this species. 相似文献
176.
Kerkmann A Kuiper H Ganter M Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(7-8):292-305
Shortness of the lower jaw (brachygnathia inferior, underbite, overshot, parrot mouth) is an inborn and mostly hereditary malformation often seen in many sheep breeds. Chromosomal anomalies are generally not involved in brachygnathia inferior. Viral infections, teratogenic drugs and alkaloids of plants often lead to craniofacial malformations associated with brachygnathia inferior. A maternal deficiency of iron is discussed as a cause for brachygnathia inferior. We performed a three-year breeding trial using mainly East Friesian milk sheep affected by brachygnathic occlusion. Mating schemes included affected by affected and affected by unaffected matings. In the breeding trial, 60 lambs were born and from these 37 animals had variable degrees of brachygnathia inferior. The brachygnathic condition increased with rising age of the lambs. Extremely affected lambs showed palatine ulcers and growth retardation. Moreover, some animals had abnormal positions of the incisor teeth, distortion of the lower jaw and deformities of the external ear. Analysis of the pedigree did not support a monogenic inheritance pattern. An oligogenic inheritance including a dominant and recessive locus responsible for the major gene effects and possibly further modifying loci appeared much more likely. Other causes for brachygnathia inferior such as viral infections and anemia of the ewes could be ruled out. Chromosomal abnormalities were not evident and thus, large chromosomal defects were not associated with brachygnathia inferior. 相似文献
177.
Comparative evaluation of six different body regions of the dog using analog and digital radiography
Meyer-Lindenberg A Ebermaier C Wolvekamp P Tellhelm B Meutstege FJ Lang J Hartung K Fehr M Nolte I 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(5-6):216-227
In this study the quality of digital and analog radiography in dogs was compared. For this purpose, three conventional radiographs (varying in exposure) and three digital radiographs (varying in MUSI-contrast [MUSI = MUlti Scale Image Contrast], the main post-processing parameter) of six different body regions of the dog were evaluated (thorax, abdomen, skull, femur, hip joints, elbow). The quality of the radiographs was evaluated by eight veterinary specialists familiar with radiographic images using a questionnaire based on details of each body region significant in obtaining a radiographic diagnosis. In the first part of the study the overall quality of the radiographs was evaluated. Within one region, 89.5% (43/48) chose a digital radiograph as the best image. Divided into analog and digital groups, the digital image with the highest MUSI-contrast was most often considered the best, while the analog image considered the best varied between the one with the medium and the one with the longest exposure time. In the second part of the study, each image was rated for the visibility of specific, diagnostically important details. After summarisation of the scores for each criterion, divided into analog and digital imaging, the digital images were rated considerably superior to conventional images. The results of image comparison revealed that digital radiographs showed better image detail than radiographs taken with the analog technique in all six areas of the body. 相似文献
178.
Domenico Santoro Andrea Spaterna Luca Mechelli Paolo Ciaramella 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(12):1204-1207
A case of canine cutaneous sterile pyogranuloma/granuloma syndrome (SPGS) with generalized asymmetrical alopecia and plaques is described. Results from histopathologic examination were suggestive of SPGS and failed to demonstrate any etiological agent. A systematic approach on how to definitively rule out infectious skin diseases is discussed. 相似文献
179.
Happy Birthday Geoff Sumner-Smith from all your friends and colleagues around the world!: Laudation.
180.