The Cambrian conundrum: early divergence and later ecological success in the early history of animals

Diverse bilaterian clades emerged apparently within a few million years during the early Cambrian, and various environmental, developmental, and ecological causes have been proposed to explain this abrupt appearance. A compilation of the patterns of fossil and molecular diversification, comparative developmental data, and information on ecological feeding strategies indicate that the major animal clades diverged many tens of millions of years before their first appearance in the fossil record, demonstrating a macroevolutionary lag between the establishment of their developmental toolkits during the Cryogenian [(850 to 635 million years ago (Ma)], and the later ecological success of metazoans during the Ediacaran (635 to 541 Ma) and Cambrian (541 to 488 Ma) periods. We argue that this diversification involved new forms of developmental regulation, as well as innovations in networks of ecological interaction within the context of permissive environmental circumstances.     

Classification of Italian honeys by 2D HR-NMR

The importance of honey has been recently increased because of its nutrient and therapeutic effects, but the adulteration of honey in terms of botanical origin has increased, too. The floral origin of honeys is usually determined using melisso-palynological analysis and organoleptic characteristics, but the application of these techniques requires some expertise. A number of papers have confirmed the possibility of characterizing honey samples by selected chemical parameters. In this study high-resolution nuclear magnetic resonance (HR-NMR) and multivariate statistical analysis methods were used to identify and classify honeys of five different floral sources. The 71 honey samples (robinia, chestnut, citrus, eucalyptus, polyfloral) were analyzed by HR-NMR using both 1H NMR and heteronuclear multiple bond correlation spectroscopy (HMBC). Spectral data were analyzed by application of unsupervised and supervised pattern recognition and multivariate statistical techniques such as principal component analysis (PCA) and general discriminant analysis (GDA). The use of 1H-(13)C HMBC coupled with appropriate statistical analysis seems to be an efficient technique for the classification of honeys.     

A simple and rapid assay for analyzing residues of carbamate insecticides in vegetables and fruits: hot water extraction followed by liquid chromatography-mass spectrometry

A simple, specific, and rapid analytical method for determining seven largely used carbamate insecticides in tomato, spinach, lettuce, zucchini, pear, and apple is here presented. This method is based on the matrix solid-phase dispersion technique, with heated water as extractant followed by liquid chromatography (LC)-mass spectrometry (MS) equipped with a single quadrupole and an electrospray ion source. Target compounds were extracted from the vegetal matrixes by water heated at 50 degrees C. After acidification and filtration, 0.25 mL of any aqueous extract was injected in the LC column. MS data acquisition was performed in the selected ion monitoring mode, selecting three ions for each target compound. Heated water appeared to be an excellent extractant because recovery data ranged between 76 (carbaryl in spinach) and 99% (pirimicarb in spinach), with RSDs not larger than 10%. Using trimethacarb (an obsolete carbamate insecticide) as a surrogate internal standard, the accuracy of the analysis varied between 84 and 110%, with RSDs not larger than 9%. On the basis of a signal-to-noise ratio of 10, limits of quantification were estimated to range between 2 (pirimicarb) and 10 ppb (oxamyl) and were not influenced by the type of matrix. When trying to fractionate analytes by using a short chromatographic run time, marked weakening of the ion signals for oxamyl, methomyl, and aldicarb were observed. This effect was traced to polar endogenous co-extractives eluted in the first part of the chromatographic run that interfered with gas-phase ion formation for carbamates. Adopting more selective chromatographic conditions eliminated this effect.     

Monitoring of Submicron Particulate Matter Concentrations in the Air of Turin City, Italy. Influence of Traffic-limitations

Several studies have shown the association between ambient particulate matter (PM) and adverse health effects, thus highlighting the need to limit the anthropogenic sources of PM, especially motor vehicle emissions. PM exposure is commonly monitored as mass concentration of PM10 or PM2.5, although increasing toxicity with decreasing aerodynamic diameter has been reported. In the present study an analysis was performed of the concentration and size distribution of airborne PM fractions collected at street level in the city center of Turin, Italy, to verify the usefulness of “ecological” days with traffic limitations. PM levels were determined daily at five different outdoor sites, from Thursday to Tuesday for 7 weeks (five with “ecological” Sunday, two with normal traffic density). Air sampling was performed using a six-channel laser particle counter to determine the number of particles (n°/l) in six size ranges between 0.3 and 10 μm. Climatic conditions and indoor PM levels were also monitored. The PM size distribution was constant for all the samples tested, with the 90% of the particles smaller than 0.5 μm, suggesting that measurements for count are needed in addition to the traditional ones based on the mass. The total number of particles was highly variable comparing days or weeks of monitoring, but much less among the sites of air sampling. The restriction of motor vehicle circulation has not determined any significant effect on PM levels and, in the winter period, PM0.5 peak concentrations were measured also on the ecological days.     

‘Net-System’ Models Versus Traditional Models in NWFP Marketing: The Case of Mushrooms

Marketing strategies for successful non-wood forest product (NWFP) commercialization are important especially in those rural economies where NWFPs represent a considerable source of income for small and medium-scale forest-based enterprises. Two different organisational models in mushrooms marketing—a ‘traditional approach’ and a ‘net-system approach’—are compared through a case-study research approach. The first model is usually based on single large-scale enterprises producing large quantities of standardized, mass-market oriented products; its main commercial goal is the improvement of the value-chain from producer to end-users, with no special links or integration between the production area and the producers. The second, quite new approach is based on several integrated small and medium-scale rural-based enterprises supplying relatively limited quantities of high quality products, oriented to niche markets. In this case, product specialty identification, complementary actions, integration, and clustering among small and medium enterprises (SMEs) within the same production area are the most important goals. In the case studies, both organisational models have proved to be feasible and working with respect to the respective goals. Traditional large-scale enterprises, based on vertical integration and a short value chain, can achieve substantial economic performance; however, these are unlikely to have a significant positive impact on the socio-economic local context and are threatened by high business risk (mainly due to its strong specialization on a ‘climate-dependent’ NWFP). The analysed forest-based business model founded on networking, which involves not only forest-based SMEs but also other institutional, economic, and social actors, has proved to be not only economically viable and less risky with respect to the traditional model, but also more equitable in distribution of benefits, and effective in stimulating the local economy as a whole, integrated system based on NWFPs and related environmental services.

Resistance to Dicarboximide Fungicides in <Emphasis Type="Italic">Stemphylium vesicarium</Emphasis> of Italian Pear Orchards

Brown spot, caused by Stemphylium vesicarium, is the main fungal disease of pear in northern Italy where it may cause severe crop losses and it requires numerous fungicide applications. Monitoring work was performed by collecting fungal populations in Po valley between 1995 and 2003 in order to study the dicarboximides resistance already detected in the 1990s for procymidone as a result of control failures in field. Sensitivity tests showed that the resistant strains occur all over the monitored areas. Where present the efficacy of procymidone in field is completely lost in spite of what is observed often in other fungi. In most of the isolates (phenotype R₁), S. vesicarium resistance level to procymidone (Sialex) was shown to be very high (RF≅3000) whereas it was lower towards the other dicarboximides iprodione (Rovral), vinclozolin (Ronilan) and chlozolinate (Serinal) (RF≅10). Therefore the resistance is partially crossed even if a high level of resistance was rarely observed for all dicarboximides (phenotype R₂). At least two different mechanisms of resistance seem to be involved: one that may provide a moderate resistance and the other that may give a high resistance level. Monospore isolate sensitivity tests confirmed the qualitative response suggested by such high resistance factors.     

Distribution,abundance, and movements of the bottlenose dolphin (Tursiops truncatus) in the Pelagos Sanctuary MPA (north‐west Mediterranean Sea)

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Phenols content and 2-D electrophoresis protein pattern: a promising tool to monitor <Emphasis Type="Italic">Posidonia</Emphasis> meadows health state

Background  

The endemic seagrass Posidonia oceanica (L.) Delile colonizes soft bottoms producing highly productive meadows that play a crucial role in coastal ecosystems dynamics. Human activities and natural events are responsible for a widespread meadows regression; to date the identification of "diagnostic" tools to monitor conservation status is a critical issue. In this study the feasibility of a novel tool to evaluate ecological impacts on Posidonia meadows has been tested. Quantification of a putative stress indicator, i.e. phenols content, has been coupled to 2-D electrophoretic protein analysis of rhizome samples.