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21.
The study has been conducted on 40 species of mammals included in different taxonomic orders: 10 carnivores (felines and canides), 13 primates and 17 herbivores (artiodactyles, perisodactyles and proboscideans). Domestic, experimental and wild animals have been included in the sample. The purpose of the study is to offer new data regarding morphometric aspects of the epithelium of the cornea of mammals. We also aim to establish the relationships and differences between the different epithelia studied and to determine the morphometric characteristics which best define the epithelium of the different species under study. The results obtained have demonstrated the existence of correlations between thicknesses, number of cellular layers and number of the epithelial cells in the different groups. It has also been established that the variants in thickness and number of layers define and characterize the epithelia. Finally, the study reveals that morphometric characteristics of the epithelium of primates and carnivores have more similarities than those of herbivores.  相似文献   
22.
From a battery of microsatellite markers (100 loci), recently identified by our group, we have selected eight for parentage assignment in Senegal sole ( Solea senegalensis ). This tool is based on microsatellite loci obtained from four genomic DNA libraries and one cDNA library. Within the eight loci (six from anonymous genomic DNA sequences and two located in expressed sequence tags of known genes), we have found, in an analysis of a reproductive broodstock, between nine and 16 alleles. The expected heterozygosity was between 0.616 and 0.860. In addition, we have optimized the polymerase chain reaction (PCR) conditions to amplify all loci simultaneously in a single multiplex PCR reaction, and we have tested three lots of male and female (five to six individuals) and three offspring (50–60 larvae each). The use of the eight microsatellite loci, the possibility of amplifying them in a single PCR reaction and the high value of the exclusion probability (0.9992) make this multiplex PCR method a unique tool for parentage assignment.
Finally, analysing one meiotic gynogenetic progeny, we have determined the relative distance of six of these loci to the centromere, and we have also found that all of them are unlinked. All these characteristics confer this tool with a high accuracy for parentage studies and genetic population analyses of Senegal sole.  相似文献   
23.
Precision Agriculture - Hedgerow orchard is an olive growing system where trees are planted at a super high-density higher than 20-fold (i.e., 1200–2500 trees ha?1) compared to the...  相似文献   
24.
The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis. Total polyphenols are distributed in a wide concentration range depending on the cultivar. Procyanidins are the class of polyphenols that present major concentrations in apple. Their average degrees of polymerization range from 4 to 8 depending on the cultivar. Apple cultivars were technologically classified into bitter and nonbitter categories using different classification systems obtained by applying several pattern recognition techniques, such as principal component analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed-forward-artificial neural networks, to apple pulp, peel, or juice data (individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins). Bitter apple cultivars present higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Detailed knowledge of the polyphenolic profile of each apple cultivar affords information about their susceptibility to oxidation, their sensory properties (bitterness, astringency), and their possible influence on the characteristics and quality of the final product (juice, cider) when apples are processed.  相似文献   
25.
The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography--diode array detection analysis of crude extracts and after thiolysis. Data sets, consisting of individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins, were evaluated by multivariate chemometric techniques, to develop decision rules for classifying apple cultivars technologically into bitter and nonbitter categories. A preliminary study of the data structure was performed by cluster analysis and principal component analysis in each apple material. Bitter apple varieties presented higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Different classification systems for the two categories on the basis of the chemical data were obtained applying several supervised pattern recognition procedures, such as linear discriminant analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed forward artificial neural networks. Excellent performance in terms of recognition and prediction abilities for both categories (100% of hits) was achieved in every case (pulp, peel, or juice). Polyphenolic profiles of apple pulp, peel, or juice provide enough information to develop classification criteria for establishing the technological group of apple cultivars (bitter or nonbitter).  相似文献   
26.
Field experiments conducted in 2007/08 and 2008/09 at the Changwu Agricultural Research Station on the Loess Plateau of China comprised three seeding rates (SR1: 225 seeds m−2, SR2: 280 seeds m−2, and SR3: 340 seeds m−2) and two root pruning treatments (W: root pruning in the over-wintering period and S: root pruning at the spring-growth stage), with the un-pruned wheat plants as controls. In the severe drought toward the end of the growing season of 2008, grain yield decreased as the seeding rate increased, but under the more favorable conditions in 2009 the reverse was true. Averaged over the seeding rates, grain yield was significantly increased in both W and S in both years; grain yield and yield components were higher in W; and S recorded the highest water use efficiency. The interaction between seeding rate and root pruning was not statistically significant. Leaf area index (LAI) and tiller density were higher as seeding rates increased whereas in W and S, increased LAI and decreased tillers significantly, but had no effect on fertile tillers. The rate of leaf photosynthesis was lower and root respiration was significantly higher at higher seeding rates, whereas in root pruning treatments, significantly higher leaf photosynthetic rate and lower root respiration were observed. Soil water contents were lower as seeding rate increased. A significant decrease in water use before stem elongation was observed in W, while S consumed less soil water than W and the control over the whole growing season. Post-heading accumulation of dry matter and its remobilization from vegetative parts to the grain was significantly greater at higher seeding rates. Post-heading accumulations of dry matter and grain yield were also significantly greater in W and S than the un-pruned plants, although pruning reduced both dry matter remobilization and its contribution to grain yield. The possibility of reducing the proliferation of roots to increase yields at higher seeding rates and conserving the soil water at different growing stages in water-limited environments is discussed.  相似文献   
27.
Genetic Resources and Crop Evolution - The biofortification of cassava (Manihot esculenta Crantz) roots is one of the actual goals of genetic breeding, with the development of roots richer in...  相似文献   
28.
Even though Brazil is a mega-diverse country, many Brazilian cities prioritize exotic plants in their treescapes. Aiming to evaluate how much the treescape in Fortaleza (the fifth largest city in Brazil) is aligned with the policy of valorization of native biodiversity, we sampled street and backyard trees surrounding one of the few vegetation fragments of the city, which is an area considered a priority for conservation. We used the vegetation fragment's flora as reference to compare the potential number of local native species with the actual number of native species in the treescape of the site. To account how much of the native flora was present in the surrounding treescape, we made an inventory of the trees in streets, squares and backyards around the vegetation and compared with the native flora of the vegetation fragment. We then compared the ratio of native to exotic species and checked how many native species of the fragment were also in the surrounding treescape. Exotics were prevalent in both number of species and number of individuals, comprising 70% of the species and 86% of the individuals of public spaces, and 79% of the species and 78% of the individuals of private spaces. Only 14% of the native species of the vegetation were also represented in the treescape, and, in general, they comprehended only a few individuals. We argue that the city's treescape should be re-evaluated in order to value native plants more. Native plants in the treescape could be used as an environmental education tool to publicize native biodiversity to citizens.  相似文献   
29.
Cytokinin amounts were determined in the ovaries of flowers and fruitlets on leafy and leafless inflorescences of seeded and seedless cultivars of Citrus sinensis, C. reshni and C. clementine. Flowers were sampled over a 65 day period from before anthesis to after fruit set, during the period from fructification to fruitlet expansion. Cytokinin activity appeared in both organic and aqueous phases obtained in the extraction process. Generally, the maximum activity in the organic phase occurred at anthesis, except in ‘Navelate’ orange, and decreased sharply following petal fall, whereas the aqueous phase had more cytokinins later, when the fruitlets had reached 1-2 cm diameter. The effect of pollination on cytokinin-like compounds was studied in seeded cultivars. The pollinated ovaries showed a peak in cytokinin activity at anthesis, in contrast to unpollinated ovaries. Partition chromatography of the organic phase on Sephadex LH-20 indicated five zones of cytokinin activity, four of which had the same elution volumes as ribosyl zeatin, zeatin, isopentenyl adenosine and isopentenyl adenine.  相似文献   
30.
The data set composed by phenolic compound profiles of 83 Citrus juices (determined by HPLC-DAD-MS/MS) was evaluated by chemometrics to differentiate them according to Citrus species (sweet orange, tangerine, lemon, and grapefruit). Cluster analysis (CA) and principal component analysis (PCA) showed natural sample grouping among Citrus species and even the Citrus subclass. Most of the information contained in the full data set can be captured if only 15 phenolic compounds (concentration ≥10 mg/L), which can be quantified with fast and accurate methods in real samples, are introduced in the models; a good classification which allows the confirmation of the authenticity of juices is achieved by linear discriminant analysis. Using this reduced data set, fast and routine methods have been developed for predicting the percentage of grapefruit in adulterated sweet orange juices using principal component regression (PCR) and partial least-squares regression (PLS). The PLS model has provided suitable estimation errors.  相似文献   
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