A procedure for the identification of the source of distortion in three-phase systems by means of the measurement of current components

The practical application of electric power theories under non-sinusoidal conditions relies on the availability of accurate and reliable methods for the identification of the source of distortion. The present paper proposes a current decomposition that allows to identify whether the source of distortion of the line signals is located after the metering section or before it. The proposed decomposition applies to three-phase systems under whatever conditions of distortion, asymmetry and unbalance. An instrument able to attain the proposed decomposition is also described and the results of some experimental work are reported as well as the measurement accuracy and sensitivity.     

A system for securing push-based distribution of XML documents

Push-based systems for distributing information through Internet are today becoming more and more popular and widely used. The widespread use of such systems raises non trivial security concerns. In particular, confidentiality, integrity and authenticity of the distributed data must be ensured. To cope with such issues, we describe here a system for securing push distribution of XML documents, which adopts digital signature and encryption techniques to ensure the above mentioned properties and allows the specification of both signature and access control policies. We also describe the implementation of the proposed system and present an extensive performance evaluation of its main components.     

LEAVES OF NERIUM OLEANDER L. AS BIOACCUMULATORS OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) IN THE AIR OF PALERMO (ITALY): EXTRACTION AND GC-MS ANALYSIS,DISTRIBUTION AND SOURCES

Polycyclic Aromatic Hydrocarbons (PAH) were determined in the leaves of Nerium oleander L. an evergreen plant that occurs widely in both urban and rural areas, to monitor the degree of pollution in the urban area of Palermo (Italy) compared to remote areas. Twenty sites (urban roadside, urban, urban park, suburban and rural) in and around Palermo city were investigated.

The purpose of this research was to investigate concentration levels and distribution patterns and relate them to possible sources. Analysis of 19 PAH was performed by gas chromatography/mass spectrometry (GCMS) using selected ion monitoring (SIM). The total amount of PAH ranged from 10 to 166 μg/Kg d.w.

Each source gives rise to a characteristic PAH pattern, and it is therefore possible to get access to the processes that generate the compounds. To this aim, the recommended as priority pollutants by the Environmental Protection Agency (EPA), perylene and three additional alkylated compounds were analyzed.

Positive correlations were found between total PAH content of the leaves with CO, benzene and particulate levels measured in air of Palermo.     

Experimental study of the thermo-mechanical properties of recycled PET fiber-reinforced concrete

This work presents an experimental study of thermal conductivity, compressive strength, first crack strength and ductility indices of recycled PET fiber-reinforced concrete (RPETFRC). We examine PET filaments industrially extruded from recycled PET bottle flakes with different mechanical properties and profiles. On considering a volumetric fiber dosage at 1%, we observe marked improvements in thermal resistance, mechanical strengths and ductility of RPETFRC, as compared to plain concrete. A comparative study with earlier literature results indicates that RPETFRC is also highly competitive over polypropylene-fiber-reinforced concrete in terms of compressive strength and fracture toughness.     

Replication casting of open-cell AlSi7Mg0.3 foams

A typical aluminum alloy for casting (AlSi7Mg0.3) was used to produce open-cell foams by replication of a salt precursor. The process was set to minimize complexity and costs of the casting operations: the preform sintering was avoided and mold temperature lower than the eutectic temperature of the alloy was used. Open-cell foams with a relative density about 35% and high compressive strength resulted. Material analyses showed that, in replication casting, the material response to the process is optimal and a homogeneous and fine grain size distribution is visible in the foams.     

Transglutaminase crosslinked pectin- and chitosan-based edible films: a review

The production of biodegradable and edible films with desired mechanical characteristics and gas barrier properties represents one of the most advanced challenges in the field of food wrapping and coating. New edible films can serve not only to provide food with physical protection but also to reduce loss of their moisture, to restrict absorption of oxygen, to lessen migration of lipids, to improve their mechanical handling features, and as materials, to apply in direct contact with internal food to realize a multilayer food packaging. Polymers derived from natural products, like carbohydrates and proteins, offer the greatest opportunities as component of edible films since their biodegradability and environmental compatibility are assured and they can also supplement the nutritional value of specific foods. However, excessive water solubility and poor water vapor barrier properties, and often poor mechanical resistance, have their application limited until the present time. Numerous studies have been carried out to improve their properties by preparing composite and multi-component films or by physically and chemically crosslinking their natural components. In the present review we summarize the main results obtained by crosslinking with the enzyme transglutaminase different proteins contained in multi-component pectin- and chitosan-based edible films, having the aim to create environmentally-friendly "bioplastics" with mechanical and permeability properties similar to the ones exhibited by plastics of petrochemical origin.     

Basestock Oils for Lubricants from Mixtures of Corn Oil and Synthetic Diesters

Environmentally friendly vegetable oils and their derivatives represent alternatives to mineral-based lubricants. Vegetable oils have high biodegradability and low production costs. Their poor thermo-oxidative stability and poor low temperature properties are disadvantages in their use as lubricant basestocks. In our study we used corn oil and diester mixtures, which become lubricants when additives are introduced. These mixtures of corn oil and di-2-ethylhexyl-adipate (DOA) and di-2-ethylhexyl-sebacate (DOS) offer a wide range of kinematic viscosities, pour points lower than −39 °C and flash points over 218 °C. The diameters of wear scars measured under four-ball testing (40 daN) are less than 0.90 mm and the copper strip corrosion test result is 1a. The differential scanning calorimetry study and thermogravimetric study under nitrogen atmosphere and in synthetic air are reported. From these studies a higher thermal stability was observed for corn oil than for diester oils. The thermo-oxidative instability occurred at temperatures higher than 350 °C. The low production cost of corn oil and its mixtures with diesters makes them an attractive alternative to mineral oil lubricants.     

Assay of tyrosol and hydroxytyrosol in olive oil by tandem mass spectrometry and isotope dilution method

Hydroxytyrosol and tyrosol, the strong antioxidant present in large amount in virgin olive oil have been assayed by LC-MS/MS under MRM condition and isotope dilution method, using d(2)-labelled internal standards obtained by simple synthetic procedures. The assay has been performed under MRM condition monitoring two transitions for each analyte to improve the specificity. This paper deals with a modern approach for assaying the content of this polyphenols in virgin olive oil down to a limit of a few hundreds of parts per billion. Tyrosol and hydroxytyrosol ranged from 10 to 47ppm and from 5 to 25ppm in commercial olive oil, respectively. The accuracy (98-107%) and analytical parameters values confirm the reliability of the proposed approach. The method can be extended to any natural matrices, including mill wastes, after a simple step of sample preparation.     

Galactose derivative immobilized glow discharge processed polyethersulfone membranes maintain the liver cell metabolic activity

New strategies aimed to surface modification of polymeric membranes are crucial to optimise cell-biomaterial interactions in vivo and in vitro biohybrid systems. In this paper, we investigated the surface modification of Polyethersulfone (PES) membranes by plasma polymerisation of acrylic acid monomers (PES-pdAA) and by immobilization of galactonic acid through a hydrophilic "spacer arm" molecule (PES-pdAA-SA-GAL). The modification steps were characterised by high resolution X-ray photoelectron spectroscopy. The performance of modified and unmodified membranes was evaluated by assessing the expression of liver specific biotransformation functions of pig and human hepatocytes. Human liver cells cultured on PES-pdAA-SA-GAL membranes displayed an enhanced albumin production, urea synthesis and protein secretion for 24 days of culture. The immobilisation of galactose derivative units on the membrane allowed specific interactions with hepatocytes biomimicking the cellular microenvironment and produced an improvement of the long-term maintenance and differentiation of human hepatocytes.     

Mitochondria Can Cross Cell Boundaries: An Overview of the Biological Relevance,Pathophysiological Implications and Therapeutic Perspectives of Intercellular Mitochondrial Transfer

Mitochondria are complex intracellular organelles traditionally identified as the powerhouses of eukaryotic cells due to their central role in bioenergetic metabolism. In recent decades, the growing interest in mitochondria research has revealed that these multifunctional organelles are more than just the cell powerhouses, playing many other key roles as signaling platforms that regulate cell metabolism, proliferation, death and immunological response. As key regulators, mitochondria, when dysfunctional, are involved in the pathogenesis of a wide range of metabolic, neurodegenerative, immune and neoplastic disorders. Far more recently, mitochondria attracted renewed attention from the scientific community for their ability of intercellular translocation that can involve whole mitochondria, mitochondrial genome or other mitochondrial components. The intercellular transport of mitochondria, defined as horizontal mitochondrial transfer, can occur in mammalian cells both in vitro and in vivo, and in physiological and pathological conditions. Mitochondrial transfer can provide an exogenous mitochondrial source, replenishing dysfunctional mitochondria, thereby improving mitochondrial faults or, as in in the case of tumor cells, changing their functional skills and response to chemotherapy. In this review, we will provide an overview of the state of the art of the up-to-date knowledge on intercellular trafficking of mitochondria by discussing its biological relevance, mode and mechanisms underlying the process and its involvement in different pathophysiological contexts, highlighting its therapeutic potential for diseases with mitochondrial dysfunction primarily involved in their pathogenesis.