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1.
Investigation of PCDDs, PCDFs, PCBs, Al, As, Pb, Ba, Co, Cu, Cr, Fe, Mn, Cd, Ag, Sn, Zn, and Hg contents in 60 samples of cold-pressed essential oils produced in Calabria and Sicily in 2003-2005 was carried out. PCDDs, PCDFs, and PCBs were analyzed by HRGC-HRMS techniques using U.S. EPA 1613/94 and U.S. EPA 1668/A (1999) analytical methods. Mineral components were determined through GFAAS techniques; Hg content was determined by FI-M/H-AAS. The results of this study showed that essential oil contamination was due to a widespread pollution, typical background of rural areas, with relatively higher concentrations of PCDDs compared to PCDFs and little presence of PeCDF. Congeners OCDD, HpCDF, and OCDF were found at high concentrations. Regarding mineral components, mean values of Cr, Fe, and Ni were in agreement with data reported in the literature. Concentrations of As and Pb were below the maximum limits accepted by the current legislation. Finally, none of the samples analyzed were contaminated with Hg.  相似文献   
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The terminal uranium nitride linkage is a fundamental target in the study of f-orbital participation in metal-ligand multiple bonding but has previously eluded characterization in an isolable molecule. Here, we report the preparation of the terminal uranium(V) nitride complex [UN(Tren(TIPS))][Na(12-crown-4)(2)] {in which Tren(TIPS) = [N(CH(2)CH(2)NSiPr(i)(3))(3)](3-) and Pr(i) = CH(CH(3))(2)} by reaction of the uranium(III) complex [U(Tren(TIPS))] with sodium azide followed by abstraction and encapsulation of the sodium cation by the polydentate crown ether 12-crown-4. Single-crystal x-ray diffraction reveals a uranium-terminal nitride bond length of 1.825(15) angstroms (where 15 is the standard uncertainty). The structural assignment is supported by means of (15)N-isotopic labeling, electronic absorption spectroscopy, magnetometry, electronic structure calculations, elemental analyses, and liberation of ammonia after treatment with water.  相似文献   
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Deep root water uptake and hydraulic redistribution (HR) have been shown to play a major role in forest ecosystems during drought, but little is known about the impact of climate change, fertilization and soil characteristics on HR and its consequences on water and carbon fluxes. Using data from three mid-rotation loblolly pine plantations, and simulations with the process-based model MuSICA, this study indicated that HR can mitigate the effects of soil drying and had important implications for carbon uptake potential and net ecosystem exchange (NEE), especially when N fertilization is considered. At the coastal site (C), characterized by deep organic soil, HR increased dry season tree transpiration (T) by up to 40%, and such an increase affected NEE through major changes in gross primary productivity (GPP). Deep-rooted trees did not necessarily translate into a large volume of HR unless soil texture allowed large water potential gradients to occur, as was the case at the sandy site (S). At the Piedmont site (P) characterized by a shallow clay-loam soil, HR was low but not negligible, representing up to 10% of T. In the absence of HR, it was predicted that at the C, S and P sites, annual GPP would have been diminished by 19, 7 and 9%, respectively. Under future climate conditions HR was predicted to be reduced by up to 25% at the C site, reducing the resilience of trees to precipitation deficits. The effect of HR on T and GPP was predicted to diminish under future conditions by 12 and 6% at the C and P sites, respectively. Under future conditions, T was predicted to stay the same at the P site, but to be marginally reduced at the C site and slightly increased at the S site. Future conditions and N fertilization would decrease T by 25% at the C site, by 15% at the P site and by 8% at the S site. At the C and S sites, GPP was estimated to increase by 18% and by >70% under future conditions, respectively, with little effect of N fertilization. At the P site, future conditions would stimulate GPP by only 12%, but future conditions plus N fertilization would increase GPP by 24%. As a consequence, in all sites, water use efficiency was predicted to improve dramatically with future conditions. Modeling the effect of reduced annual precipitation indicated that limited water availability would decrease all carbon fluxes, including NEE and respiration. Our simulations highlight the interactive effects of nutrients and elevated CO(2), and showed that the effect of N fertilization would be greater under future climate conditions.  相似文献   
5.
An 8‐month‐old intact male English Setter was presented with bilateral shoulder lameness. Radiographic and CT examinations demonstrated bilateral irregular margination and separation of the supraglenoid tubercle from the scapula, with involvement of the cranial articular surface of the glenoid cavity. After 30 days of cage rest, complete fusion of proximal portions of both supraglenoid tubercles and persistent un‐united cranial portions of both glenoid cavities were evident. Histopathologic findings from biopsies of glenoid cavity defects were consistent with osteochondrosis or focal chondrodysplasia.  相似文献   
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Italian pasta must be prepared using exclusively durum wheat. According to current Italian rules, only a maximum of 3% Triticum aestivum is allowed to account for cross-contamination that may occur during the agricultural process. Efficient methods for the detection of accidental or intentional contamination of common wheat to durum wheat products are therefore required. This article describes a novel approach for the detection and quantification of soft wheat adulteration in whole grain durum flours and dried pasta. The assay relies on the presence of intron-specific DNA length polymorphisms in the plant β-tubulin gene family, which can be highlighted through the PCR-based TBP (Tubulin-Based Polymorphism) method. In wheat, the TBP method produces species-specific amplification products, which can be either directly used as new DNA molecular markers capable of discriminating between T. aestivum and Triticum durum or analyzed at the sequence level for the design of species-specific probes. The latter approach allowed the development of new sequence-specific targets that can be exploited in RT-PCR assays for a rapid and accurate quantification of soft wheat adulteration in durum wheat pasta.  相似文献   
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Between May 2007 and October 2008, 34 outbreaks of mild to moderate forms of infectious laryngotracheitis (ILT) occurred in commercial broiler flocks in Italy. Affected birds showed watery eyes, conjunctivitis, nasal discharge, reduction of feed and water consumption, and gasping with expectoration of blood-stained mucus. The mortality rate was < 10%. Gross lesions consisted of conjunctivitis, excess of mucus, blood, or presence of diphtheritic membranes in trachea. A real-time PCR assay was performed to confirm the presence of ILT virus (ILTV) DNA in tracheal tissue homogenates. Twenty-three ILTV isolates were propagated on the chorion-allantoic membrane of embryonated chicken eggs showing typical plaques. PCR combined with restriction fragment length polymorphism and gene sequencing of isolates showed a high genetic correlation between field strains and chicken embryo origin vaccines.  相似文献   
8.
A multidisciplinary study was carried out over four years in Northern Italy on a silt loam under continuous maize. The experimental design was a split-plot with four replicates; the main factor was the soil management system, conventional tillage (CT) or no-tillage (NT), while the secondary factor was N fertilisation. At the end of the trial, soil samples were taken from all plots at four depths (from 0 to 20 cm). In these samples the following were determined: pH, soil organic carbon (SOC), total N, available P, exchangeable K, cation exchange capacity (CEC), electrical conductivity (EC) and water aggregate stability (WAS). Soil compaction was measured during the last three years, after maize harvesting. To study the microarthropod community, soil samples (0–10 cm depth) were taken six times over the four years. Our results show that NT significantly increased SOC (+15.8%), total N (+9.6%), C/N (+5.3%), exchangeable K (+37.1%) and WAS (+64.8%). The stratification ratio for exchangeable K reached 2.15 for NT plots. N fertilisation, on the other hand, had no significant effect on most of the physico-chemical indicators, except for pH, CEC and EC. Soil compaction was significantly higher for NT compared with CT up to a depth of 25–30 cm. During the last year, interesting reductions in soil penetration resistance for NT were measured, up to 300–430 kPa in the 2.5–12.5 cm layer. As for the microarthropods, Acari were more sensitive to tillage compared with Collembola, and the Wardle V index proved to be a good indicator of the response to tillage. N fertilisation with 300 kg N ha−1 had a negative effect on the total microarthropod abundance. The Shannon diversity index gave fluctuating and significantly different results: over the years results were split alternately between the two tillage systems. The QBS-ar index, calculated for all the four years of the study, ranged between 48 and 72, values typical of intensively cultivated soils. The results obtained suggested that it was not influenced by the tillage system. Therefore, this index seems to be unsuitable for detecting the influence of tillage management and N fertilisation on the microarthropod community.  相似文献   
9.
Italian lentil landraces are principally cultivated for self or local consumption. Most of them are disappearing, particularly macrosperma types by being less required by the market. A pre-requisite for the conservation and the efficient use of genetic resources is the better understanding of the extent and the distribution of the existing genetic variation, useful for future breeding programmes. Our study was undertaken to analyse and quantify the genetic diversity within and among three macrosperma Italian lentil landraces (Onano, Altamura and Villalba), using fluorescent AFLP markers. AFLP markers generated information to differentiate among closely related genotypes and group within the same cluster individuals belonging to the same landrace. The total genetic diversity (HT), the genetic diversity within population (HS) and the extent of differentiation between populations (DST) were 0.198, 0.155 and 0.043, respectively. The fixation index (GST = 0.219) showed that about 78% of the observed total genetic variation can be attributed to within population differences and around 22% is due to differences among populations. The gene flow estimate (Nm = 1.774) and the mean genetic distance value (0.077) suggested narrow genetic base among the analysed populations, confirming the tendency of Italian lentil landraces to group together. The present study showed that fluorescence-based AFLP technique is a biotechnological tool that can provide significant insights for research in genetic diversity of lentil landraces and their subsequent conservation and utilization in breeding programs.  相似文献   
10.
Blood lactate concentrations were determined in 16 horses (three Thoroughbreds, seven Standardbreds and six polo ponies) before and 5 mins after they galloped over distances of 200, 300 and 400 m at maximal speed. The highest net lactate concentration (delta Lamax) of 14 to 15 mmol/litre was attained by the polo ponies and the highest speed by the Thoroughbreds. The maximal rate of lactate production (delta L?max) was about 35 mmol/litre X min for the polo ponies and 20 to 25 mmol/litre X min for the Standardbreds and the Thoroughbreds. Values for delta Lamax and delta L?max were similar to those measured in human athletes after exhaustive work. delta L?max increases with the speed (v) and can be described by the equation delta L? = a (v-v1), where a is a proportionality constant representing the amount of lactate needed to cover a unit distance and v1 the theoretical speed at which delta L? = 0 X v1 was highest for the Thoroughbreds and lowest for the polo ponies; this difference could be caused by the effect of training and/or to genetic differences among the different breeds of horses X v1 could be a useful index of the fitness of a horse following a training programme.  相似文献   
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