Giuseppe Provenzano

Hepatitis C virus replication in 'autoimmune' chronic hepatitis.

Both high and low anti-hepatitis C virus antibody (anti-HCV) prevalence has been reported in autoimmune chronic active hepatitis. Therefore, we studied 15 consecutive HBsAg-negative, ELISA anti-HCV-positive, autoantibody-positive patients with biopsy proven chronic active hepatitis in order to confirm ELISA specificity by immunoblot test (RIBA-HCV), and to evaluate HCV replication by serum HCV-RNA. Nine patients were anti-nuclear, three type 1 anti-liver-kidney microsomal and three anti-smooth muscle antibody positive. None had associated autoimmune disease. All cases showed mild clinical disease and only moderate necroinflammatory activity. Response to prednisone was poor. RIBA-HCV confirmed ELISA results in all patients. HCV-RNA was found in the serum from 10 patients. Institution of alpha-interferon treatment in three steroid non-responsive patients was followed by prompt normalization of transaminases. Thus, a subgroup of autoantibody-positive chronic active hepatitis can be recognized as HCV-related and should be clinically and etiologically distinguished from autoimmune chronic active hepatitis. Trials of alpha-interferon treatment are worthwhile in this condition.

Multicentre randomized placebo‐controlled trial of ursodeoxycholic acid with or without colchicine in symptomatic primary biliary cirrhosis

To establish the efficacy of combination therapy with ursodeoxycholic acid (UDCA) and colchicine in patients with symptomatic primary biliary cirrhosis (PBC), defined by the presence of liver cirrhosis, pruritus or bilirubin exceeding 2 mg/mL.

Assessing Field and Laboratory Calibration Protocols for the Diviner 2000 Probe in a Range of Soils with Different Textures

AbstractFrequency domain reflectometry (FDR) downhole sensors have been increasingly used for soil moisture field monitoring because they allow measurement, even continuously, along a soil profile. Moreover, they can also be installed with minimal soil disturbance around the access tube. The objectives of the paper were to assess the field and laboratory calibration protocols for a FDR capacitance probe (Diviner 2000) for a range of soils characterized by different particle size distributions and shrink/swell potential and to propose a practical and effective protocol on the basis of undisturbed soil samples, accounting for soil shrinkage/swelling processes characterizing swelling clay soils. The experiments showed that on coarse-textured soils, field calibration under wet, moist, and dry conditions allows estimations of the volumetric soil water content, with root-mean-square error (RMSE) values always lower than 0.058  cm3·cm−3. On the contrary, the problems occurring in the field on finer-textured soil...

Integrated Emitter Local Loss Prediction Using Artificial Neural Networks

This paper describes an application of artificial neural networks (ANNs) to the prediction of local losses from integrated emitters. First, the optimum input-output combination was determined. Then, the mapping capability of ANNs and regression models was compared. Afterwards, a five-input ANN model, which considers pipe and emitter internal diameter, emitter length, emitter spacing, and pipe discharge, was used to develop a local losses predicting tool which was obtained from different training strategies while taking into account a completely independent test set. Finally, a performance index was evaluated for the test emitter models studied. Emitter data with low reliability were removed from the process. Performance indexes over 80% were obtained for the remaining test emitters.

Immunoblotting as a confirmatory test for antimitochondrial antibodies in primary biliary cirrhosis.

Primary biliary cirrhosis is characterised by the presence of antimitochondrial antibodies which are directed against components of mitochondrial dehydrogenase complexes. The specificity of antimitochondrial antibodies for primary biliary cirrhosis as detected by immunoblotting was investigated. Commercially available preparations of pyruvate and oxo-glutarate dehydrogenases and beef-heart mitochondria were used as source of antigens. Sera from 47 primary biliary cirrhosis patients (46 of whom were antimitochondrial antibody positive by immunofluorescence), 16 non-primary biliary cirrhosis patients (antimitochondrial antibody positive by immunofluorescence), 23 liver-kidney microsomal antibody positive chronic active hepatitis patients, and 32 patients with connective tissue diseases were examined. Of the 47 subjects with primary biliary cirrhosis, 43 (91%) and 13 (28%) tested positive by immunoblotting for pyruvate and oxo-glutarate dehydrogenase, respectively. Only three primary biliary cirrhosis patients were negative for both antigens, including the only one shown to be antimitochondrial antibody negative by immunofluorescence. The other two patients were positive by immunoblotting with beef-heart mitochondria. In contrast, only three of 16 (19%) non-primary biliary cirrhosis patients who were antimitochondrial antibody positive by immunofluorescence tested positive by immunoblotting (for both pyruvate dehydrogenase and beef-heart mitochondria). None of the 23 liver-kidney microsomal antibody positive and the 32 patients with rheumatic diseases were positive by immunoblotting with any antigen. Our data show that immunoblotting with commercially available oxo-acid dehydrogenases is a reproducible method for the detection of antimitochondrial antibodies highly specific for primary biliary cirrhosis.

Analysis of geometrical relationships and friction losses in small-diameter lay-flat polyethylene pipes

AbstractThe use of lay-flat polyethylene pipes to irrigate horticultural crops has been receiving widespread attention in the last decade, due to the significant improvements in their hydraulic performance, their potentially high application efficiency, and their limited installation costs. However, even if hydraulic design procedures for conventional microirrigation systems are fairly well established, there is still the need to know how different pipe-wall thicknesses of lay-flat pipes can affect the pipe geometry under different operating pressures as well as the related consequences on friction losses. This paper, after comparing two different procedures (caliper and photographic) to assess the geometry of lay-flat polyethylene pipes under different operating pressures, analyzes the friction losses per unit of pipe length, J, in order to identify and to assess a procedure for their evaluation. Hydrostatic tests, initially carried out on pipes with wall thicknesses of 6, 8, and 10 thousandth of an inch...

Assessing a Local Losses Evaluation Procedure for Low-Pressure Lay-Flat Drip Laterals

AbstractIn the past, several research experiments have focused on the hydraulic characterization of traditional drip irrigation systems, and different design methodologies have been proposed with the aim of achieving very high emitter discharge uniformity (EU). The increasing use of low-pressure lay-flat drip laterals, characterized by a thin-walled polyethylene pipe, makes necessary a specific determination of their hydraulic properties, aimed to a correct design of such systems. Here, the validity of an empirical local losses estimation model was assessed for five different commercial lay-flat drip tapes. Moreover, the errors in the maximum lateral lengths obtained for a fixed emitter uniformity, when the local losses are neglected or empirically estimated, were evaluated. The step by step (SBS) procedure was then implemented to model the hydraulic behavior of each tested lateral with values of the upstream pressure head different than those investigated. The experiments demonstrated that under the exam...

Determining Optimal Seasonal Irrigation Depth Based on Field Irrigation Uniformity and Economic Evaluations: Application for Onion Crop

AbstractThe crop water production function (WPF), representing the relationship between crop yield and seasonal irrigation water, is a useful tool for irrigation planning purposes. The objective of the paper is to propose a methodology to evaluate the optimal seasonal irrigation depth based on the crop production function, the field distribution uniformity, and economic considerations. An extended unpublished database experimentally obtained on the onion crop on the island of Kula, Hawaii, was initially used to assess the crop WPF. The combination between the crop WPF and the model representing the field distribution uniformity allowed determining the area subjected to underirrigation and overirrigation, as well as the corresponding yield, that were finally averaged across the field. An economic comparison was also carried out in order to evaluate the optimal seasonal water depth aimed at maximizing the farmer’s gross margin under different irrigation system distribution uniformities and water prices. Acc...

Special Issue on Trends and Challenges of Sustainable Irrigated Agriculture

In the twenty-first century, the shortage of freshwater is one of the most important environmental concerns facing several regions of the world because of the growing demand of increasing population, agricultural intensification, and economic growth. Global climate change will contribute to exacerbate the problem, generating new drought-prone areas and increasing those already characterized by severe aridity. Worldwide it is estimated that, on average, agriculture accounts for 70% of the total water consumption, compared with 10% for domestic consume and the remaining used by industry. Moreover, according to FAO estimates, by 2050 agricultural production has to increase by 60% to satisfy the demands for food and feed (FAO 2013). Within this context, it is necessary to think back and make effective policies and actions for enhancing rational land use planning and agricultural inputs for a better exploitation of the existing technologies, even to rise the farmers’ awareness on the consequences of water scarcity. Sustainable agriculture must therefore be prescribed as a policy approach to maximize production while maintaining environmental quality in a fragile and quite stressed environment (Provenzano et al. 2013; Cammalleri et al. 2013b). It requires the conversion of current agricultural practices toward systems more productive and resilient to climate variability, in which land, water, and other inputs would be more efficiently used, and crops yield would be less variable. Heading forward to achieve these goals, shortand long-term strategies across different and integrated pathways are required. These would have to keep in mind issues such as food security and agricultural development, and take into account the existing environmental constrains. According to FAO (2013), climate-smart agriculture (CSA) would be an integrated approach to achieve the goals of a sustainable development. It addresses the food security and climate challenges issues within the economic, social, and environmental dimensions of sustainable development. Considering that in irrigated agriculture, water resources (both quantity and quality) are one of the major environmental constrains, which will intensify in the future, there is a priority for water management agents and stakeholders to consider its use sustainable. Thus, it is required and no longer postponed to improve technologies and approaches to optimize water use at different scales (farm, field, district, and higher). On the one hand, it is necessary to increase the performance of irrigation systems, and on the other hand, it is crucial to adopt technologies for irrigation scheduling aimed to increase water use efficiency, avoiding wastes and losses. This special issue reports the results of some research presented in the session 11.3. Soil and Irrigation Sustainability Practices, at the European Geoscience Union general assembly, held in Vienna in 2012, related, as summarized below, to applications of on-farm control sensors aimed to increase effectiveness of irrigation, to methodologies for improving agrohydrological models predictions, as well as to practices of good management in different cropsystems. The contributions of the papers in this volume are not intended to get into an exhaustive detail of the above issues; nevertheless, they highlight some advice to implement actions toward a more sustainable management of irrigated agriculture. Playan et al. (2014) describe the importance of investment in water-efficient technologies aiming at maximizing economic return in on-farm irrigation systems. Then, present a list of existing opportunities that, under particular conditions, allows to maximize irrigation efficiency and water productivity overpassing the unsatisfactory water use efficiency, often recognized at farm level. In particular, agrohydrological models and soil sensors have been successfully used to control landscape irrigation, whereas intelligent and autonomous systems are effectively applied to monitor the climate and to drive the complex water and nutrient application in greenhouses. In addition, the development of affordable systems for drip irrigated orchards, for irrigation machines, and for solidsets sprinkler irrigation still remain in the domain of science and technology. In fact, according to the authors, in drip irrigated orchards with automated deficit irrigation, the need of a high number of sensors for the continuous and precise monitoring of soil and crop water status, as well as the required skills, often limit this methodology. Moreover, for self-propelled sprinkler irrigation machines, the main concern still remains in the difficulty of set input application to field variability despite the progress in automation and also in the possibility of adaption under different soil-crop systems. The paper finally presents an on-farm controller device driven by simulation models that can be used for a solid set sprinkler system, in order to reduce the effects of meteorological conditions on wind drift and evaporation losses. The opportunities and the limitation of their different alternatives, according to sitespecific conditions, are illustrated and discussed. A methodology to derive standardized reference evapotranspiration zone maps by daily climate data and GIS is proposed in the paper by Mancosu et al. (2014) that describes its application for Sardinia region (Italy). The characterization of irrigated zones by class of reference evapotranspiration open the window to evaluate crop water requirements on large areas and/or to investigate the impact of climate change. Reference evapotranspiration was estimated by means of the UN-FAO Penman Monteith equation (PM), as later modified by ASCE-EWRI, for the meteorological stations providing the full required dataset (solar radiation, air temperature, wind speed, relative humidity). Likewise, for meteorological stations providing only air temperature (partial data), it is shown that the PM equation generally provides better estimations of reference evapotranspiration than the Hargreaves-Samani equation, even

Assessing actual evapotranspiration via surface energy balance aiming to optimize water and energy consumption in large scale pressurized irrigation systems

Satellite imagery provides a dependable basis for computational models that aimed to determine actual evapotranspiration (ET) by surface energy balance. Satellite-based models enables quantifying ET over large areas for a wide range of applications, such as monitoring water distribution, managing irrigation and assessing irrigation systems’ performance. With the aim to evaluate the energy and water consumption of a large scale on-turn pressurized irrigation system in the district of Aguas Nuevas, Albacete, Spain, the satellite-based image-processing model SEBAL was used for calculating actual ET. The model has been applied to quantify instantaneous, daily, and seasonal actual ET over high- resolution Landsat images for the peak water demand season (May to September) and for the years 2006 – 2008. The model provided a direct estimation of the distribution of main energy fluxes, at the instant when the satellite overpassed over each field of the district. The image acquisition day Evapotranspiration (ET24) was obtained from instantaneous values by assuming a constant evaporative fraction (Λ) for the entire day of acquisition; then, monthly and seasonal ET were estimated from the daily evapotranspiration (ETdaily) assuming that ET24 varies in proportion to reference ET (ETr) at the meteorological station, thus accounting for day to day variation in meteorological forcing. The comparison between the hydrants water consumption and the actual evapotranspiration, considering an irrigation efficiency of 85%, showed that a considerable amount of water and energy can be saved at district level.