Monovarietal extra virgin olive oils: correlation between thermal properties and chemical composition

Thermal properties of monovarietal extra virgin olive oils were evaluated by means of differential scanning calorimetry (upon cooling) and related to their chemical composition (triacylglycerols, diacylglycerols, total and free fatty acids, oxidation status). The overall crystallization enthalpy did not significantly differ among samples and did not account for the differences observed in chemical compositions. On the contrary, a higher degree of unsaturation in the lipid profile induced a shift of the crystallization onset towards lower temperatures and narrowing of the crystallization temperature range. The presence of triacylglycerol lysis and lipid oxidation products shifted the crystallization towards higher temperatures and the phase transition developed over a larger temperature range. Differential scanning calorimetry thermograms were deconvoluted into three constituent exothermic peaks for all samples. The area of the two lower-temperature exotherms was found to be statistically correlated with the amount of triunsaturated and monosaturated triacylglycerols present in the oil. Thermal properties of extra virgin olive oil were found to be affected by oil chemical composition.     

Plant and animal diversity in a region of the Southern Alps: the role of environmental and spatial processes

Different organisms respond to landscape configuration and spatial structure in different terms and across different spatial scales. Here, regression models with variation partitioning were applied to determine relative influence of the three groups of variables (climate, land use and environmental heterogeneity) and spatial structure variables on plant, bird, orthopteran and butterfly species richness in a region of the Southern Alps, ranging in elevation from the sea level to 2,780 m. Grassland and forest cover were positively correlated with species richness in both taxonomic groups, whilst species richness decreased with increasing urban elements and arable land. The variation was mainly explained by the shared component between the three groups in plants and between landscape and environmental heterogeneity in birds. The variation was related to independent land use effect in insects. The distribution in species richness was spatially structured for plants, birds and orthopterans, whilst in butterflies, no spatial structure was detected. Plant richness was associated with linear trend variation and broad-scale spatial structure in the northern part of the region, whilst bird richness with broad-scale variation which occurs on the external Alpine ridge. Orthopteran diversity was strongly related to fine-scale spatial structure, generated by dynamic processes or by unmeasured spatially structured abiotic factors. Although the study was carried out in relatively small area, the four taxonomic groups seem to respond to biodiversity drivers in a surprisingly different way. This has considerable implications for conservation planning as it restricts the usefulness of simple indicators in prioritizing areas for conservation purposes.     

The effects of drug detection training on behavioral reactivity and blood neurotransmitter levels in drug detection dogs: A preliminary study

The aim of the present study was to analyze the effects of drug detection training on behavior and blood neurotransmitter levels in drug detection dogs so as to investigate some variables influencing dog reactivity and responsiveness to training. In all, 20 dogs were sampled out of the Guardia di Finanza canine population. All the subjects were born, reared, housed, and trained in the same facility and followed the same training sessions. Dogs’ behavioral reactivity was scored according to a standardized working dogs test to evaluate natural dog attitudes. Plasma samples were analyzed by the high-performance liquid chromatography method to evaluate adrenaline, noradrenaline, L-3,4-dihydroxyphenylalanine, homovanillic acid (HVA), 3-methoxy-4-hydroxyphenylglycol acid (MHPG), 5-hydroxyindole acetic acid (5-HIAA), and 5-hydroxytryptamine (5-HT) levels. 5-HT and 5-HIAA were also analyzed from platelets. The analysis was carried out considering training, breed, and sex as independent variables. From a behavioral point of view, significant differences were recorded before and after training in “sociability,” “playfulness,” “predatory instinct,” and “aggressiveness” scores. Lower levels of platelet 5-HT and 5-HIAA were found after training. Plasma L-3,4-dihydroxyphenylalanine levels differed between sexes, with males showing higher concentrations. These results underline the importance of complete and objective evaluations protocols of the dogs before, during, and after drugs search training to determine effective and successful selection strategies and training procedures.     

Prevalence and concentration of Verotoxigenic Escherichia coli O157:H7 in adult sheep at slaughter from Italy

A 1-year study on the animal-level prevalence and concentration of Escherichia coli O157 in adult sheep at slaughter was performed, to collect qualitative and quantitative information on the diffusion of the pathogen in adult sheep from Italy. A total 533 samples were collected, with a similar distribution in the four seasons. For prevalence estimates, a simple random sampling technique was used. An immuno-magnetic separation technique was used for sample screening, with enumeration of the pathogen in positive samples, along with molecular and serological identification of isolates. An overall prevalence of 7.1% (38/ 533, 95% CI 4.9-9.3%) was observed for fully virulent E. coli O157. A wide interval of VTEC O157 per gram was observed (< 100 to 6 x 10(5) CFU g(-1)), with 28.9% (11/38) of positive samples > or = 1 x 10(3) CFU g(-1), set as the threshold for those animals defined 'active shedders' for the purpose of the study. Eight per cent (3/38) of animals shed > 1 x 10(4) g(-1) VTEC O157, which represents > 96% of the total VTEC O157 bacteria cultured from all animals tested. The prevalence estimate of active shedders was therefore 2.1% (95% CI 0.9-3.3%). Most (34/38, 89.5%) of the positive animals were found in summer (July-September). Prevalence and concentrations of virulent VTEC O157 obtained in this study contribute to the demonstration that adult sheep represent a relevant source of environmental contamination from virulent VTEC O157, as well as a source of VTEC O157 contamination for food of ovine origin (meat and dairy products), especially during warm months.     

The influence of land abandonment on forest disturbance regimes: a global review

Landscape Ecology - Since the nineteenth century, rural areas have experienced progressive abandonment mostly due to socioeconomic changes, with direct and indirect effects on forest disturbance...     

Predicting the response of nekton assemblages to seagrass transplantations in the Venice lagoon: An approach to assess ecological restoration

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SSR markers reveal the uniqueness of olive cultivars from the Italian region of Liguria

Twenty-three important Ligurian olive accessions corresponding to 16 cultivars were studied using 12 SSR markers and 40 Mediterranean cultivars were included in the study in order to investigate the relationships between Ligurian and Mediterranean germplasm. All SSRs produced polymorphic amplifications. One hundred and forty-nine alleles were found in the 63 accessions analysed. Twenty-two alleles were specific to germplasm from Liguria and of these 12 were unique to single cultivars. Heterozygosity and discriminating power calculated in this regional germplasm were high on average (0.70 and 0.74) and not so much lower than the values in the total sample that includes cultivars from different Mediterranean countries (0.77 and 0.88 respectively). No cases of genetic identities were found between Ligurian and Mediterranean accessions. Several cases of homonyms and synonyms within the Ligurian germplasm were explained. Cluster analysis generally revealed a clear discrimination of the profiles from Liguria and Italy with respect to the cultivars from other Mediterranean countries. Only one Ligurian cultivar, “Negrea”, appeared to have a different origin, grouping with the Mediterranean cultivars.