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The epidermis of plant shoot organs is generally covered by epicuticular waxes. The role of this layer is related mainly to the protection of the inner tissues from biotic and abiotic stresses. In this study, attention is focused on the optical properties of the berry epicuticular waxes of the grapevine (Vitis vinifera L.) at fruit ripening. The relectance of the berry surface was measured before and after chloroform treatments in four Georgian grape cultivars grown in northern Italy. Epicarp optical properties were underlined at different wavelengths (341 to 1025 nm) for each cultivar. The results show that the berry waxes have several optical properties; it is possible that their main eco-physiological effect is to provide speciic protection against different types of radiation. Besides the physiological aspects, the results are interesting also from a technical point of view in the ield of interpretation of relectance measurements carried out by non-invasive instruments. [ABSTRACT FROM AUTHOR]

We apply a measurement technique that utilizes thermal video of vapor-dominated volcanic plumes to estimate the HO gas flux at three degassing volcanoes. Results are compared with HO flux measurements obtained using other methods to verify the thermal camera-derived values. Our estimation of the HO emission rate is based on the mass and energy conservation equations. HO flux is quantified by extracting the temperature and width of the gas plume from the thermal images, calculating the transit velocity of the gas plume from the thermal video, and combining these results with atmospheric parameters measured on-site. These data are then input into the equations for conservation of mass and energy. Selected volcanoes for this study were Villarrica in Chile, Stromboli in Italy, and Santa Ana in El Salvador. HO fluxes estimated from the thermal imagery were 38-250 kg s at Villarrica, 4.5-14 kg s for Stromboli's Central Crater, and 168-219 kg s at Santa Ana. These compare with HO flux values estimated by other methods of 73-220, 3-70 and 266 kg s, at the three volcanoes, respectively. The good agreement between thermal image-derived results and those estimated by other methods seem to validate this method. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal venting occurs on numerous volcanoes of various age, setting, topographic and structural expression. Vent locations are commonly found not within volcanic craters only, but predominantly at the crater margins and topographic highs. A case example is Vulcano Island, Italy, where the control on such vent locations along crater margins remained poorly understood, however. This paper describes numerical models combined with field observations and infrared imaging to explore the mechanisms that control the ascent paths of fluids in the Fossa cone on Vulcano. Using finite element modelling we calculate the gravitational stress in the volcanic edifice imposed by the topography. Results predict hydrofractures to be arranged in radial patterns at depth and in concentric patterns close to the surface. Furthermore, low compressive stress values are found at the rims of the nested craters. We compare the stress models to fumarole field data: Using a forward looking infrared camera we recorded images of the entire cone. Images were assembled to a mosaic and geocoded, providing the first map of a remotely sensed temperature field in high resolution at La Fossa. The degassing and high temperature anomalies are found to be located mainly at the crests of the craters, predominately in the northern and southern sector of the main crater. Therefore, the stress distribution favours and indeed corresponds to the occurrence of fumaroles at La Fossa. The stress models also yield compression at the bottom of the crater where temperatures are cool. Thus, we consider that the overall distribution of the fumaroles at the Fossa cone is controlled by topography. Additional mechanisms contribute to the exact position of the degassing sites: The influence of the lithological control seems to be strong in the southwestern part of the crater where the fumaroles are located 10–20m below the inner crater rim in bedded strata. In the northern part of the crater, the exhalation sites can mainly be found at surface fractures and cracks emphasizing the structural control on the location of the fumaroles at this sector of the Fossa cone. Using combined theoretical modelling and field observations, this study helps to shed light into the processes directing fluids in volcanic edifices elsewhere and might contribute to the evaluation of upcoming hazard scenarios. [Copyright &y& Elsevier]

One-hundred and fourteen samples of saffron harvested in four different Italian areas (three in Central Italy and one in the South) were investigated by IR and UV-Vis spectroscopies. Two different multi-block strategies, Sequential and Orthogonalized Partial Least Squares Linear Discriminant Analysis (SO-PLS-LDA) and Sequential and Orthogonalized Covariance Selection Linear Discriminant Analysis (SO-CovSel-LDA), were used to simultaneously handle the two data blocks and classify samples according to their geographical origin. Both multi-block approaches provided very satisfying results. Each model was investigated in order to understand which spectral variables contribute the most to the discrimination of samples, i.e., to the characterization of saffron harvested in the four different areas. The most accurate solution was provided by SO-PLS-LDA, which only misclassified three test samples over 31 (in external validation). [ABSTRACT FROM AUTHOR]