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1.
Possible correlations among several environmental factors and the internal phenol content and oxidative enzyme activities of olive explants were examined. The statistic analysis revealed that the same environmental factor exhibited different relation with the various individual phenolic compounds found in explants and the oxidative enzyme activities. The major contribution of air temperature, total radiation, soil temperature at a depth of 25 cm and photoperiod on the explant phenol content and on the oxidative enzyme activities has been revealed. These environmental factors exhibited the highest number of significant relationships with the measured variables.  相似文献   
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To elucidate the photochemical behavior of pesticide metolachlor, degradation was carried out in aqueous media of different compositions such as sea, river, lake, and distilled water under natural and simulated solar irradiation. In addition, the effect of important constituents of natural water such as dissolved organic matter (DOM, isolated from Pamvotis Lake) and nitrate ions was also examined. It was found that photodegradation proceeds via a pseudo-first-order reaction in all cases. The presence of DOM inhibits the photolysis reaction with half-lives ranging from 87 to 693 h whereas the degradation rate was accelerated up to 11 times in the presence of NO(3)(-). In addition, the toxicity of the degradation products formed (generally through hydroxylation, dealkylation, and cyclization reactions) was also performed using the marine luminescent bacterium Vibrio fisheri. Our results indicated a toxicity increase of the irradiated solution showing that photoproducts of higher acute toxic effects were formed.  相似文献   
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Water availability is an important factor for irrigated agriculture in the Mediterranean countries, because it affects significantly crop production. Surface soil samples were collected in Merambelo area located in Eastern Crete and analyzed. High values for exchangeable potassium and magnesium values were recorded and can be attributed to intensive fertilization and soil heredity factors. Groundwater quality based on two sampling campaigns performed during two irrigation periods. Three different scenarios were taken into account regarding the height of water application by means of irrigation. The contribution and the effects of nutrients and micronutrients from irrigation water to the soil was calculated, on the basis of the mean determined concentrations and the volume of applied irrigation. Significant variation was recorded in most soil properties, and these differences may be attributed to different mobility of nutrients, erosion factors, fertilization practices, and hydraulic soil properties.  相似文献   
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Pagellus erythrinus culture was carried out from the fertilizable egg to the larval stage at different temperatures: 15°, 18°, and 21°C for the embryonic stage and 16°, 18°, and 21°C for yolk-sac and larval stages. Total length and variability, growth rate, duration of each stage, hatching percentage, survival of each developmental stage, efficiency of vitelline and lipid utilization, and the percentages of morpho-anatomical abnormalities were used as criteria for the evaluation of temperature's influence on culture of Pagellus erythrinus. A temperature of 18°C favors the early life stages culture of Pagellus erythrinus.  相似文献   
7.

Background

We conducted a study in order to determine the usefulness and diagnostic value of International Autoimmune Hepatitis Group (IAHG) score in non-autoimmune hepatitis (AIH) hepatic disorders as well as in AIH/overlap syndromes and in cases with coexistence of AIH and other liver diseases.

Methods

We applied the IAHG score in 423 patients with liver diseases excluding patients with AIH, AIH/overlap syndromes and AIH with concurrent other liver disease namely, patients with chronic hepatitis B (n = 109), chronic hepatitis C (n = 95), chronic hepatitis D (n = 4), alchoholic liver disease (n = 28), non-alcoholic fatty liver disease (n = 55), autoimmune cholestatic liver diseases (n = 77), liver disorders of undefined origin (n = 32) and with miscellaneous hepatic disorders (n = 23). 24 patients with AIH associated with any kind of liver disorder including 10 patients with AIH/overlap syndromes and 14 AIH with concurrent other liver disease were also investigated. 43 patients with AIH consisted the control group.

Results

The specificity of the score was 98.1% while the sensitivity in unmasking AIH in patients with either AIH/overlap syndromes or AIH with concurrent other liver diseases was only 50% and 78.6%. In the binary logistic regression model, the presence of other autoimmune diseases (p < 0.001), the total histological score (p < 0.001) and positivity for autoantibodies (p < 0.05) were identified as independent predictors for the presnce of AIH/ovea syndromes o AI with concurren other liver diseass.

Conclusion

The IAHG scoring system has very good specificity for excluding AIH in patients with chronic liver diseases but not that sensitivity in order to unmask AIH/overlap syndromes or AIH with concurrent other liver diseases. The presence of other autoimmune diseases or autoantibody markers in the absence of hepatitis viral markers should alarm physicians for the possible presence of AIH either as "pure" AIH or in association with other liver disorders (AIH/overlap syndromes or AIH with concurrent other liver diseases). Under these conditions, liver histology seems essential and it must always be included in the work up of hepatic patients.
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ABSTRACT

The present work investigates the impact of municipal solid waste mechanical separation and industrial composting on the metal content of composts and assesses the availability of Cu, Cd, Cr, Pb, and Zn at different maturation stages of compost produced at the largest mechanical biological treatment plant in Greece. Substantial metal contamination of composts was found to take place within the industrial facility, attributed to segmentation and sorption mechanisms during composting. In fresh compost, Zn is present in mobile fractions (41%), Cu is mostly held on the less mobile organic phases (57%), Cd is mostly present in bioavailable forms (51%), whereas Pb and Cr are associated with less mobile phases, such as Fe-Mn oxides and organic molecules. Cd, Cu, and Zn migrate to more inert phases during compost maturation, paralleled by the decrease of overall metal leachability. Cu and Pb concentrations (mg kg?1) exceeded the permissible limits in both composts (Fresh: Cu: 213 ± 48, Pb: 128 ± 69; Mature: Cu: 263 ± 1, Pb: 158 ± 29) and water leachates (Fresh: Cu: 106 ± 4, Zn: 126 ± 13; Mature: Cu: 50 ± 0.50, Zn: 118 ± 20). Nevertheless, toxic effects were not observed in monocot, dicot, or aquatic biosensor plants as indicated by radicle and shoot growth and visual quality ratings. Since metal availability in composts is related to their leaching potential, metal speciation studies should be conducted in leachates for the appropriate characterization of industrial composts.  相似文献   
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Hybridization and introgression between Quercus alnifolia Poech and Q. coccifera L. is studied by analyzing morphological traits, nuclear and chloroplast DNA markers. The study site is a mixed stand on Troodos Mountains (Cyprus), and the analyzed material includes both adult trees and progenies of specific mother trees. Multivariate analysis of morphological traits shows that the two species can be well distinguished using simple leaf morphometric parameters. A lower genetic diversity in Q. alnifolia than in Q. coccifera and a high interspecific differentiation between the two species are supported by an analysis of nuclear and chloroplast microsatellites. The intermediacy of the four designated hybrids is verified by both leaf morphometric and genetic data. Analysis of progeny arrays provides evidence that interspecific crossings are rare. This finding is further supported by limited introgression of chloroplast genomes. Reproductive barriers (e.g. asynchronous phenology, postzygotic incompatibilities) might account for this result. A directionality of interspecific gene flow is indicated by a genetic assignment analysis of effective pollen clouds with Q. alnifolia acting as pollen donor. Differences in flowering phenology and species distribution in the stand may have influenced the direction of gene flow and the genetic differentiation among effective pollen clouds of different mother trees within species.  相似文献   
10.
The evergreen Quercus alnifolia and Q. coccifera form the only interfertile pair of oak species growing in Cyprus. Hybridization between the two species has already been observed and studied morphologically. However, little evidence exists about the extent of genetic introgression. In the present study, we aimed to study the effects of introgressive hybridization mutually on both chloroplast and nuclear genomes. We sampled both pure and mixed populations of Q. alnifolia and Q. coccifera from several locations across their distribution area in Cyprus. We analyzed the genetic variation within and between species by conducting analysis of molecular variance (AMOVA) based on nuclear microsatellites. Population genetic structure and levels of admixture were studied by means of a Bayesian analysis (STRUCTURE simulation analysis). Chloroplast DNA microsatellites were used for a spatial analysis of genetic barriers. The main part of the nuclear genetic variation was explained by partition into species groups. High interspecific differentiation and low admixture of nuclear genomes, both in pure and mixed populations, support limited genetic introgression between Q. alnifolia and Q. coccifera in Cyprus. On the contrary, chloroplast DNA haplotypes were shared between the species and were locally structured suggesting cytoplasmic introgression. Occasional hybridization events followed by backcrossings with both parental species might lead to this pattern of genetic differentiation.  相似文献   
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