Accumulation of polychlorinated biphenyls and organochlorine pesticide in pet cats and dogs: Assessment of toxicological status

PCB and DDT concentrations were determined in the adipose tissue of cats and dogs from Southern Italy. In cats p,p′-DDE was the most abundant DDT component (95.0%), while in dogs these compounds were absent, except in two specimens. PCB concentrations were higher in cats (199.02 ng g^− 1 lipid weight) than in dogs (41.61 ng g^− 1 lipid weight). Also there were inter-specific differences in the contribution of the different congeners to PCBs, although PCB 138, PCB 153 and PCB 180 were the most representative congeners in both species. Animals from one location, Taranto City, had significantly elevated concentrations of dioxin-like PCBs compared to the other locations. Consequently the estimated mean 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) of coplanar PCBs were higher in these animals (cats: 0.65 pg g^− 1 lipid weight; dogs 0.29 pg g^− 1 lipid weight) than in the other ones (cats: 0.12 pg g^− 1 lipid weight; dogs: 0.001 pg g^− 1 lipid weight).     

Evidence for the combined participation of a C10 and a C15 precursor in the biosynthesis of moenocinol, the lipid part of the moenomycin antibiotics

Upon feeding of [2-(13)C,4-(2)H]-1-deoxy-D-xylulose to Streptomyces ghanaensis, the deuterium label was retained exclusively at positions C-7 and C-17 in the moenocinol part of the moenomycin antibiotics. This result vindicates the hypothesis that the C(25) structure of moenocinol is assembled from a C(10) and a C(15) precursor, each of which requires for its formation the involvement of a dimethylallyl diphosphate starter unit.     

XML document indexes: a classification

XML's increasing diffusion makes efficient XML query processing and indexing all the more critical. Given the semistructured nature of XML documents, however, general query processing techniques won't work. Researchers have proposed several specialized indexing methods that offer query processors efficient access to XML documents, although none are yet fully implemented in commercial products. In this article the classification of XML indexing techniques identifies current practices and trends, offering insight into how developers can improve query processing and select the best solution for particular contexts.     

An anelastic spectroscopy, differential scanning calorimetry and X-ray diffraction study of the crystallization process of Mg–Ni–Fe alloys

The effects of heating-induced crystallization on the structural and mechanical properties of Mg–Ni–Fe amorphous ribbons were studied by anelastic spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction. DSC results show that the crystallization occurs through several non-reversible steps, which correspond to significant changes in the Young's modulus and concomitant irreversible elastic energy loss peaks. Moreover, an anelastic peak is found at 215 K, which for the first time indicates the presence of some dynamical process related to the simultaneous presence of different phases. The formation of a metastable Mg₆Ni phase is detected, which transforms into Mg and Mg₂Ni stable phases. A quantitative analysis of the different phases present at the different steps was also carried out.     

Quality factors and grades for the classification and standardisation of complex ready pasta meals

The aim of this study is to arrive at a new classification of ready pasta meals, through the evaluation of their global quality, since their growing number, present in the market, often may be cause of confusion to consumers, because the parameters that contribute to the quality level are not clearly identifiable and measurable. After having explored several possible quality factors, we arrived at the conclusion that at least five must be taken into consideration: degree of pulping of the pasta, capacity to hold the sauce, weight constancy, wholeness and defects. Then, three quality grades are here proposed and discussed. Particular emphasis should be given to the sauce, because it highly influences on the global quality of these foodstuffs.     

Real-Time PCR-Based Ready-to-Use Multi-Target Analytical System for GMO Detection

This paper describes the development, production, and testing of a high-throughput analytical system, i.e., a unique screening tool for the unequivocal simultaneous identification of all currently EU-approved and all unapproved genetically modified organisms (GMOs) known to the Community Reference Laboratory for GM Food and Feed (CRL-GMFF), established according to Regulation (EC) No 1829/2003. The rationale and comparative advantage of the strategy selected as well as the formulation, potentiality, and flexibility of the system are illustrated here. The approach, developed in response to the worldwide growing testing needs, allows the event-specific simultaneous detection of 39 single-insert GMOs and their derived stacked events. System performance (specificity, efficiency, etc) has been successfully confirmed by experimental testing conducted within the CRL-GMFF and in collaboration with European control laboratories. The limit of detection (LOD) has been determined to be at least 0.045% expressed in haploid genome copies, thus in full compliance with EU requirements for method LOD. The “real-time PCR-based ready-to-use multi-target analytical system for GMO detection” developed by the Joint Research Centre is the first analytical tool worldwide allowing the simultaneous detection of so many genetic modification events using event-specific targets.     

Hydrochemistry of the high-boron groundwaters of the Cornia aquifer (Tuscany, Italy)

The groundwaters of the Cornia River alluvial aquifer (southern Tuscany) were studied to determine the origin of their characteristic high-boron content. The interpretation is based on concentrations of major ions and selected minor and trace elements (B, Br, F, and Li). Mass balance calculations confirm that the main processes in the entire system are mixing of three water types and cation exchange between waters and sediments. The observed geochemical patterns indicate that the Ca-HCO₃ waters recharging the aquifer interact with the alluvial sediments, increasing the TDS contents of the groundwaters without changing their chemical facies. High SO₄ (up to 1840 mg/l) and F (up to 2.6 mg/l) thermal (hot) waters are discharged at several points in the Cornia basin. These Ca-SO₄ waters mix with the Ca-HCO₃ waters in the upstream part of the basin. Near the coastline, seawater intrusion occurs as a result of over-pumping, giving rise to Na-Cl-dominated waters near the shore. Further inland, within the transition zone between fresh and salty waters, cation exchange on the clay fraction of the aquifer leads to a loss of Na and a gain of Ca, shifting the composition towards Ca-Cl and mixed-anion waters. Interaction with clay minerals explains the higher contents of B and Li in the Cornia groundwaters than in the seawater.The geochemical data, presented in the form of GIS-based geochemical maps, provide a baseline that can be used as a useful diagnostic tool to monitor the hydrochemical evolution of the Cornia groundwaters in view of possible future degradation of their quality in response to natural causes and human activities, including geothermal developments in the general Larderello area.     

A new radiation detector made of multi-walled carbon nanotubes

We report first results on a microstrip radiation detector made of multi-walled carbon nanotubes directly grown on a sapphire substrate between platinum electrodes. Signals induced in nanotubes by pulsed laser beams have been collected and analysed at three different wavelengths, 355, 532 and 1064 nm. Improvement of sensitivity towards UV wavelengths has been observed reflecting the shape of the absorbance spectrum of material. Signals clearly indicate the production of charges and the subsequent transport in the direction of the applied electric field. Measurement of the charge amount collected at different drain voltages as well as the detection efficiency are reported for each of the three wavelengths exploited.     

Scaled-up production of a promising Mg-based hydride for hydrogen storage

The feasibility of scaling up the production of a Mg-based hydride as material for solid state hydrogen storage is demonstrated in the present work. Magnesium hydride, added with a Zr–Ni alloy as catalyst, was treated in an attritor-type ball mill, suitable to process a quantity of 0.5–1 kg of material. SEM–EDS examination showed that after milling the catalyst was well distributed among the magnesium hydride crystallites. Thermodynamic and kinetic properties determined by a Sievert's type apparatus showed that the semi-industrial product kept the main properties of the material prepared at the laboratory scale. The maximum amount of stored hydrogen reached values between 5.3 and 5.6 wt% and the hydriding and dehydriding times were of the order of few minutes at about 300 °C.