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Deficit irrigation may be used to control canopy development, yield, and fruit composition in order to enhance fruit colour, texture, and juice composition. The present study was carried out in 2007 using five-year old Lambrusco grapevines grown with the root system split into two pots. Water stress was applied on half of the vines (stressed) by withholding water from one out of the two pots from pre-veraison till harvest. At harvest, yield and cluster number per vine were recorded. Leaves and berries were collected and their mineral composition analyzed. Samples of 200-berries were collected to obtain qualitative parameters and to investigate mechanical properties using a TAxT2i Texture Analyzer. In order to confirm berry skin values obtained using texture analysis, microscope observations were made on frozen samples. Berry development (cluster and berry weight) was reduced by water stress; yield, sugar concentration, acidity and pH were similar between treatments, while malic acid and potassium concentrations in control vines were greater than in stressed vines. Water stress significantly enhanced the total anthocyanins. Mechanical properties of berries were strongly affected by water stress, showing a significant increase of berry skin thickness and a decrease of firmness. Microscope observations confirmed greater skin thickness as a result of water stress. Calcium, Mg, and B content in leaves and in berries significantly changed when water stress conditions were imposed. Sulphur and Mn content in leaves and P content in berries were also affected by treatment. These changes probably resulted from differential uptake and flow of nutrients from leaves to berries under water stress. In particular low Ca in leaves and high Ca levels in berries were registered in stressed vines, indicating the important role of Ca in enhancing berry skin thickness. The same pattern of flow from leaves to berries was noticed for Mg. In contrast, low levels of B were found both in leav

The BaR-SPOrt experiment is designed to measure the E-mode power spectrum of the Cosmic Microwave Background Polarization (CMBP) in the multipole range 50 < I < 1000. In the current configuration at 32 GHz it can explore up to l = 400. Recent low frequency observations of the target region show that the synchrotron emission should not contamine the CMBP already at 32 GHz. A 6month observation of a 6° × 6° sky area during the polar night, in ideal environmental conditions, will allow the Italian-French collaboration to both measure the E-mode power spectrum with appropriate sensitivity and perform important tests of the anomalous dust emission. The BaR-SPOrt 32 GHz instrument, now under test and ready for operations by Spring 2005, is proposed for 1-2 years Winter operations at Dome C.

The BaR-SPOrt (Balloon-Borne Radiometers for Sky Polarization Observations) experiment, a program of the Agenzia Spaziale Italiana (ASI) co-funded by PNRA (Progetto Nazionale di Ricerca in Antartide) was originally designed as a payload for long duration balloons flights. The changing scenario, both scientific and strategic, has led us to propose it for the starting winter campaign of at the Concordia Base. Here the instrument and the features making it suitable to operate at Dome-C are described. After the initial setup, BaR-SPOrt should not require any kind of routine intervention by a dedicated base staff. The experiment will just need electrical power (less than 2 kW) and a suitable accommodation on the field. It can be fully monitored and controlled, including the data acquisition, through its own telemetry/telecommand link using IRIDIUM modems. Both the receiver and the critical electronics are housed inside a temperature-controlled vacuum chamber, providing the properly stabilized environment. The cold part of the radiometer employs a closed loop mechanical cryo-cooler that provides temperatures < 70 +/- 0.1 K with low power consumption (< 200 W).

The Sky Polarization Observatory (SPOrt) is an ASI-funded experiment specifically designed to measure the sky polarization at 22, 32 and 90 GHz, which was selected in 1997 by ESA to be flown on the International Space Station. Starting in 2006 and for at least 18 months, it will be taking direct and simultaneous measurements of the Stokes parameters Q and U at 660 sky pixels, with FWHM=7°. Due to development efforts over the past few years, the design specifications have been significantly improved with respect to the first proposal. Here we present an up-to-date description of the instrument, which now warrants a pixel sensitivity of 1.7 K for the polarization of the cosmic background radiation, assuming two years of observations. We discuss SPOrt scientific goals in the light of WMAP results, in particular in connection with the emerging double-reionization cosmological scenario.