Irrigated agriculture plays a vital role for the socio-economic development of the Mediterranean area, although it has significant impacts on both water and energy resources. Therefore, in a context in which water resources are also experiencing increasing pressures, there is an urgent need for supporting their sustainable management. This may be an extremely challenging task, especially at the local scale, due to the several interconnected dynamics affecting the state of a complex irrigation system. In fact, multiple actors are involved in decision-making processes, and the use of natural resources (and their mutual interactions) strongly depends on their behaviors, which affect the system as a whole. In this context, the present study proposes an integrated methodology, based on the Water Energy Food Nexus (WEFN), specifically focused on the sustainable management of water resources for irrigation. Firstly, a model based on Causal Loop Diagrams (CLD) is developed in order to get a deep insight into the key dynamics behind a complex irrigation system. Secondly, three indices based on the “footprint” concept are identified, in order to synthesize such dynamics. The integration of these two approaches support investigating the whole system and, particularly, understanding the influence of multiple decisional actors on it, as well as the role of a set of key drivers and constraints. This might also allow drawing some relevant conclusions, useful for supporting effective decisions oriented to a sustainable water resources management. Specific reference is made to a case study, the Capitanata irrigation system, located in the Southern Italy.
The initiation of matrix microcracking was investigated in unidirectional glass matrix composites having controlled fiber spacing. Observations were taken from composites consisting of regular arrays of TiB2-coated SIGMA 1240 and carbon-coated SCS-6 monofilament SiC fibers in a series of borosilicate glasses. The thermal expansion mismatch between the fibers and glass matrix was varied such that the resulting radial stresses after processing ranged from tensile to compressive. The glass strongly bonds to the TiB2-coated SIGMA 1240 fiber but weakly bonds to the carbon coating of the SCS-6 fiber, allowing the investigation of the effects of bonding at the fiber/matrix interface. The observed crack initiation stresses of the various composites are compared to predictions based on a previously developed semiempirical model and used to study the influence of the volume fraction of fibers, residual stress state and interface strength. 相似文献
Sol–gel derived silica (SiO2) films doped with nickel oxide (NiO) nanocrystals were fabricated. A bifunctional ligand was used, bearing amine groups capable of coordinating the nickel ions and hydrolysable siloxane groups for anchoring the metal complex moiety to the silicate matrix. Nickel oxide nanocrystals precipitated at 500°C while the film was still porous. The nanocomposite films showed a reversible change in the optical transmittance in the VIS-NIR range when exposed to carbon monoxide gas. The effects of residual porosity, testing temperature, and carbon monoxide gas concentration on optical transmittance were studied. 相似文献
Axi-symmetric compression and focusing of a low temperature laser produced copper plasma with an electrostatic plasma optical system was investigated for the first time. The degree of plasma concentration was quantified using Langmuir ion measurements of the ion flow and optical measurements of the thickness distributions of copper depositions on glass substrates. Both the ion flow and the deposition measurements showed strong concentration of the ion-plasma flow towards the axis. The ion current density at the focus was compressed by a factor up to 9. The on-axis deposition rate was increased by about the same factor. 相似文献
Important pumice quarries are located on the island of Lipari (Italy) where an intense activity of extraction, transformation and trade of pumice takes place. Nevertheless, the finest fraction amounting to about 60% of mined pumice is discarded and disposed off in open-sky pits. This implies economic losses for mining industries and environmental problems for neighbouring villages. In order to find a sustainable use of this waste, we resumed and improved an old extractive process with aqueous sodium alkali, where a sodium silicate concentrated solution was produced together with an unextracted residue partially converted into zeolite P in Na+ form and now we are searching for suitable applications of this residue. In this paper, we relate about its use as a low cost water softening agent on the basis of results obtained from several tests both in batch systems and column. They show that, at room temperature, the residue works well with calcium and badly with magnesium, whereas, at 60 degrees C, also the affinity toward Mg ions increases to acceptable levels. Repeated regenerations of the residue with concentrated NaCl solutions do not appreciably compromise the performance. The limits for the possible use as water softening agent are defined. 相似文献
Extracellular vesicles (EVs) are promising therapeutic tools in the treatment of cardiovascular disorders. We have recently shown that EVs from patients with Acute Coronary Syndrome (ACS) undergoing sham pre-conditioning, before percutaneous coronary intervention (PCI) were cardio-protective, while EVs from patients experiencing remote ischemic pre-conditioning (RIPC) failed to induce protection against ischemia/reperfusion Injury (IRI). No data on EVs from ACS patients recovered after PCI are currently available. Therefore, we herein investigated the cardio-protective properties of EVs, collected after PCI from the same patients. EVs recovered from 30 patients randomly assigned (1:1) to RIPC (EV-RIPC) or sham procedures (EV-naive) ({"type":"clinical-trial","attrs":{"text":"NCT02195726","term_id":"NCT02195726"}}NCT02195726) were characterized by TEM, FACS and Western blot analysis and evaluated for their mRNA content. The impact of EVs on hypoxia/reoxygenation damage and IRI, as well as the cardio-protective signaling pathways, were investigated in vitro (HMEC-1 + H9c2 co-culture) and ex vivo (isolated rat heart). Both EV-naive and EV-RIPC failed to drive cardio-protection both in vitro and ex vivo. Consistently, EV treatment failed to activate the canonical cardio-protective pathways. Specifically, PCI reduced the EV-naive Dusp6 mRNA content, found to be crucial for their cardio-protective action, and upregulated some stress- and cell-cycle-related genes in EV-RIPC. We provide the first evidence that in ACS patients, PCI reprograms the EV cargo, impairing EV-naive cardio-protective properties without improving EV-RIPC functional capability. 相似文献
In this paper a two-dimensional (2-D) dynamic model, based on a tensor formulation and solved numerically by combining finite elements and finite differences, is proposed and used for analyzing nematic liquid crystal (LC) test cells with interdigital electrodes. We compare theoretical and experimental results concerning the switching behavior, response mechanism, and viewing angle characteristics of nematic LC pixel structures which use the in-plane-switching (IPS) mode. The good agreement observed between theory and experiment in terms of electro-optical properties validates our modeling and demonstrates its potential for design optimization. We show that the proposed LC test cells, using the in-plane-switching mode, ensure switching-ON and -OFF response times of 22 and 28 ms, respectively, and excellent viewing angle characteristics 相似文献
The calibration in frequency of piezoelectric transducers can be obtained by sending an ultrashort laser pulse (30 ps), generated by a mode-locked Nd:YAG laser, directly on the detector surface. Thanks to its short duration, the mode-locked pulse behaves as an excitation source of wide spectral content, so that the spectral analysis of the recorded electric signal gives direct information about the frequency response of the probe. In particular, we report a series of measurements on various transducers of several nominal frequencies and we show the different response of the probe to a focused laser beam to that of an unfocused one. 相似文献