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Recent studies have shown that there are many effects of climate change on aeroallergens, and thus on allergic diseases in humans. In the Mediterranean region, despite the importance of the olive tree for production, there is high allergenicity of olive pollen and related risks to human health. Aerobiological sampling techniques can be used to analyse the pollinosis phenomenon through determination of mean daily pollen concentrations per cubic metre of air. The present study was carried out from 1999 to 2008 in 16 olive-growing areas in Italy, to update the information on the pollinosis characteristics of Olea europaea in the study areas. The analysis of the average flowering season over the study period highlights a temporal scaling of pollen in the atmosphere that depends on the different climatic characteristics. This is mainly dependent on temperature, and in part, determined by latitude. Generally, the levels of O. europaea pollen in the atmosphere are higher from mid-April to the end of June, with the period of greatest risk to human health due to this olive pollen in this area currently limited primarily to the last 10 days of May. However, the pollen season can move, depending on the climate scenario considered, and data here can be used to determine potential time shifts in pollinosis that might cause more precocious asthma and allergy problems. The allergy season for this type of pollen might be significantly precocious in future decades (20–30 days earlier in the year), which will impact on the severity and duration of allergies attributable to olive tree pollen.  相似文献   
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The Lagoon of Venice is a transitional environment suffering from industrial, urban and agricultural impact. Recently the mechanical clam fishing, preventing a regular deposition of sediments has made sampling of cores suitable for radiodating very problematic. Therefore, in this study, in order to assess temporal and spatial trends of contamination, the same sampling scheme was repeated three times over a 12-year period. The concentrations of PCBs, PAHs and organochlorine pesticides were measured in the uppermost 5 cm of sediments collected in 25 sites in the central portion of the lagoon during three campaigns conducted in 1987, 1993 and 1998. Analytical results, validated statistically, indicated that, while PCB and pesticide concentrations tend to decrease during the considered period of time, PAH do not, showing that the input rate of these compounds to the lagoon environment is still important. A spatial trend of pollution was also found in the lagoon for PCBs and pesticides, which decrease from the sources, namely the industrial zone and the mouths of rivers, to areas closer to the sea: a reduction up to 80% and 90%, respectively, was monitored. PAH contamination, originating chiefly from incomplete combustion of fossil fuels, as inferred from ratios of congeners, was mainly located around the historical center of Venice, where most of the boat traffic is concentrated and has an increasing trend.  相似文献   
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The analysis of habitat selection in radio-tagged animals is approached by comparing the portions of use against the portions of availability observed for each habitat type. Since data are linearly dependent with singular variance-covariance matrices, standard multivariate statistical tests cannot be applied. To bypass the problem, compositional data analysis is customarily performed via log-ratio transform of sample observations. The procedure is criticized in this paper, emphasizing the several drawbacks which may arise from the use of compositional analysis. An alternative nonparametric solution is proposed in the framework of multiple testing. The habitat use is assessed separately for each habitat type by means of the sign test performed on the original observations. The resulting p values are combined in an overall test statistic whose significance is determined permuting sample observations. The theoretical findings of the paper are checked by simulation studies. Applications to case studies previously considered in literature are discussed.  相似文献   
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Omphalopagus conjoined twins were diagnosed by ultrasonography in a pregnant woman at 21 weeks' gestation. In order to clarify the anatomical connections, magnetic resonance imaging (MRI) was performed, having achieved fetal paralysis by intravascular injection of 100 mg of pancuronium into each twin. Prior to MRI, 2 ml of a 0.0001 mmol/ml solution of gadolinium DTPA was also injected into the stomach of one twin. The contrast agent opacified the bowel loops of both twins, indicating bowel to bowel anastomosis. Following pregnancy termination, autopsy confirmed the prenatal diagnosis.  相似文献   
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Environmental Science and Pollution Research - Microplastic pollution is one of the greatest environmental concerns for contemporary times and the future. In the last years, the number of...  相似文献   
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Public healthcare wastes from the region of Ribeirão Preto, Brazil, pre-sterilized in an autoclave, were inoculated with spores of Bacillus atrophaeus for microwave processing on a laboratory scale. The influence of waste moisture (40%, 50% and 60% wet basis), presence of surfactant, power per unit mass of waste (100, 150 and 200 W/kg) and radiation exposure time (from 5 to 40 min) on the heating curves was investigated. The most favorable conditions for waste heating with respect to moisture and use of surfactant were then applied in an experimental analysis of the degree of inactivation of B. atrophaeus spores as a function of time and power per unit mass of waste. Based on Chick’s and Arrhenius laws, the experimental results were adjusted by the least squares method to determine the activation energies (9203–5782 J/mol) and the Arrhenius pre-exponential factor (0.23 min?1). The kinetic parameters thus obtained enabled us to predict the degree of inactivation achieved for B. atrophaeus spores in typical healthcare waste. The activation energy was found to decrease as the power per waste mass increased, leading to the conclusion that, in addition to the thermal effect on the inactivation of B. atrophaeus spores, there was an effect inherent to radiation.  相似文献   
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We present and compare results obtained from the analysis of polychlorinated biphenyls (PCBs) of a limited number of contaminated soil samples collected in three areas of Basilicata region (south of Italy). The levels of PCBs were evaluated by using two analytical methods: (i) parallel dual-column gas-chromatography with dual electron capture detectors (GC-ECD) and (ii) gas-chromatography coupled to high-resolution mass spectrometry (GC-HRMS) via electron impact ionization (EI) in the multiple ion monitoring mode (MIM, two ions per compound). Two extraction methods prior to sample cleanup were also examined: microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE). The MAE was the extraction procedure adopted using acetone/n-hexane (1:1, v/v) as it is mainly characterized by higher sample throughput and allowed reduced consumption of organic solvents. While extraction and analysis of spiked soil samples showed the applicability of both methods, systematic differences between the results were obtained for the sum of PCBs as a result of some non-detected congeners by GC-ECD compared with GC-HRMS. Indeed, high resolution MS using EI mode (electron energy 40eV) with a resolving power of 10,000 provides additional information about the contamination pattern. The GC-ECD screening of 11 soil samples led to just one sample non-compliant to as it was close to the guide value for soils fixed by the Italian legislation (i.e., 60ppb for private or urban soil). Using GC-HRMS, the amount of all PCBs found ranged from 5.4 to 127ppb with five soil samples non-compliant to the guide value. The number of identified congeners ranged from 1 to 9 and 9 to 18 using dual-column GC-ECD and GC-HRMS, respectively.  相似文献   
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