Papers by Selected Lecturers at the 11th International Symposium on Non-thermal/Thermal Plasma Pollution Control Technology & Sustainable Energy (ISNTPT 11)

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Risk allocation and incentives for private contractors: an analysis of Italian project financing contracts

Based on the economic literature and international comparison, the paper examines the adequacy of the terms of Italian project financing contracts to build and operate public works, and identifies potential areas for improvement. We analyze the main contractual content of the public works construction and management concessions submitted to the Project Financing Technical Unit with a view to monitoring public-private contract partnerships. Overall, the analysis reveals the backwardness of the Italian system and the existence of not insignificant problem areas. The survey supports the need to foster adequate standardization of contracts in Italy aimed, in particular, at ensuring: i) the provision of more appropriate mechanisms for the employment of penalties for breach of contract by the concessionaire, especially in the management phase, and – conversely – of reward mechanisms; ii) the inclusion of clauses relative to the sharing of financing documents by the contracting authorities; iii) appropriate attention to the quantitative elements of the business plan; and iv) the strengthening of supervisory activity of the grantor during the various phases of the contract.project financing, regulation, risk allocation

Oxidation of clofibric acid in aqueous solution using a non-thermal plasma discharge or gamma radiation

In this work, we study degradation of clofibric acid (CFA) in aqueous solution using either ionizing radiation from a $^{60}$Co source or a non-thermal plasma produced by discharges in the air above the solution. The results obtained with the two technologies are compared in terms of effectiveness of CFA degradation and its by-products. In both cases the CFA degradation follows a quasi-exponential decay in time well modelled by a kinetic scheme which considers the competition between CFA and all reaction intermediates for the reactive species generated in solution as well as the amount of the end product formed. A new degradation law is deduced to explain the results. Although the end-product CO$_2$ was detected and the CFA conversion found to be very high under the studied conditions, HPLC analysis reveals several degradation intermediates still bearing the aromatic ring with the chlorine substituent. The extent of mineralization is rather limited. The energy yield is found to be higher in the gamma radiation experiments.Comment: 25 pages, 7 figure

Cold plasma for green advanced reduction/oxidation processes (AROPs) of organic pollutants in water

Cold plasma is gaining increasing attention as a novel tool to activate energy demanding chemical processes, including advanced reduction/oxidation processes (AROPs) of organic pollutants in water. The very complex milieu generated by discharges at the water/plasma interface comprises photons, strong oxidants and strong reductants which can be exploited for achieving the degradation of most any kind of pollutants. Despite the complexity of these systems, the powerful arsenal of mechanistic tools and chemical probes of physical organic chemists can be usefully applied to understand and develop plasma chemistry. Specifically, the added value of air plasma generated by in situ discharge with respect to ozonation (ex situ discharge) is demonstrated using phenol and various phenol derivatives and mechanistic evidence for the prevailing role of hydroxyl radicals in the initial attack is presented. On the reduction front, the impressive performance of cold plasma in inducing the degradation of recalcitrant perfluoroalkyl substances, which do not react with OH radicals but are attacked by electrons, is reported and discussed. The widely different reactivities of perfluorooctanoic acid (PFOA) and of perfluorobutanoic acid (PFBA) underline the crucial role played in these processes by the interface between plasma and solution and the surfactant properties of the treated pollutants

New water-soluble carbamate ester derivatives of resveratrol

Low bioavailability severely hinders exploitation of the biomedical potential of resveratrol. Extensive phase-II metabolism and poor water solubility contribute to lowering the concentrations of resveratrol in the bloodstream after oral administration. Prodrugs may provide a solution—protection of the phenolic functions hinders conjugative metabolism and can be exploited to modulate the physicochemical properties of the compound. We report here the synthesis and characterization of carbamate ester derivatives of resveratrol bearing on each nitrogen atom a methyl group and either a methoxy-poly(ethylene glycol)-350 (mPEG-350) or a butyl-glucosyl promoiety conferring high water solubility. Ex vivo absorption studies revealed that the butyl-glucosyl conjugate, unlike the mPEG-350 one, is able to permeate the intestinal wall. In vivo pharmacokinetics confirmed absorption after oral administration and showed that no hydrolysis of the carbamate groups takes place. Thus, sugar groups can be attached to resveratrol to obtain soluble derivatives maintaining to some degree the ability to permeate biomembranes, perhaps by facilitated or active transport

Management of craniofacial development in the Parry-Romberg syndrome: Report of two patients

Objective: The aim of this article is to describe the orthodontic therapy for Parry-Romberg syndrome. The therapeutic goal is to minimize the wasting effects of progressive atrophy on facial development of a part of the face. Design: To correct problems affecting craniofacial development of these patients, occurring during puberty, an orthodontic appliance was employed, which helps maintain parallelism of the facial planes, in particular the mandibular plane. Setting: Orthodontic care was carried out in the Dental Clinic of the Catholic University of the Sacred Heart of Rome. Intervention: Two patients underwent orthodontic therapy for 6 years. Appliances were checked every month and modified periodically so as to adapt to facial bone growth. Results: At the end of craniofacial growth, the mandible was almost symmetric and the problem relating to atrophy remained confined to the initial area. Cephalometric analyses demonstrated that the occlusal plane and the mandibular plane maintained a straight orientation in relation to the bizygomatic plane. The ratio between the left and right side of the ramus and condyle, in the mandible, improved. Conclusions: The use of orthodontic therapy allows patients affected by hemifacial progressive atrophy to present a more harmonic face at the end of puberty when final reconstruction can be planned. These results provide for a limitation of surgical intervention to the sclerodermic area alone

Chapter Pollutant Degradation in Gas Streams by means of Non-Thermal Plasmas

Biomedical engineerin

On the use of microwaves during combustion/calcination of N-doped TiO2 precursor: An EMW absorption study combined with TGA-DSC-FTIR results

For the first time, dielectric properties and electromagnetic wave (EMW) absorbing performance of a precursor for N-doped TiO2 nanoparticles undergoing combustion synthesis are reported. The precursor contains titania, NH4Cl as source of N atoms for TiO2 nanoparticles doping, and organics. Thermogravimetric analysis (TGA) reveals that the 180-450 degrees C temperature range accounts for the overall weight loss of the process. High -temperature gas evolution analysis confirms combustion of the organic component. Aiming to optimize output power and time schedule of the material's microwave (MW) calcination, in situ high temperature dielectric properties measurements were recorded during MW irradiation in a dedicated cavity. Results revealed that after a first stage of non-combustive decomposition, in a second stage the EMW absorption decreases, so MW power is no longer necessary and hybrid heating is suggested to reach the desired calcination temperature (375-400 degrees C)

pH-Controlled Liposomes for Enhanced Cell Penetration in Tumor Environment

An innovative pH-switchable colloidal system that can be exploited for site-selective anticancer drug delivery has been generated by liposome decoration with a new novel synthetic non-peptidic oligo-arginine cell-penetration enhancer (CPE) and a quenching PEGylated counterpart that detaches from the vesicle surface under the acidic conditions of tumors. The CPE module (Arg(4)-DAG) is formed by four arginine units conjugated to a first-generation (G1) 2,2-bis(hydroxymethyl)propionic acid (bis-MPA)/2,2-bis(aminomethyl)propionic acid (bis-AMPA) polyester dendron terminating with 1,2-distearoyl-3-azidopropane for liposome bilayer insertion. The zeta potential of the Arg(4)-DAG-decorated liposomes increased up to +32 mV as the Arg(4)-DAG/lipids molar ratio increased. The Arg(4)-DAG liposome shielding at pH 7.4 was provided by methoxy-PEGS(5 kDa)-polymethacryloyl sulfadimethoxine (mPEG(5) (kDa)-SDM8) with 7.1 apparent pK(a). Zeta potential, surface plasmon resonance and synchrotron small-angle X-ray scattering analyses showed that at pH 7.4 mPEG(5) (kDa)-SDM8 associates with polycationic Arg(4)-DAG-decorated liposomes yielding liposomes with neutral zeta potential. At pH 6.5, which mimics the tumor environment, mPEG(5) (kDa)-SDM8 detaches from the liposome surface yielding Arg(4)-DAG exposure. Flow cytometry and confocal microscopy showed a 30-fold higher HeLa cancer cell association of the Arg(4)-DAG-decorated liposomes compared to non-decorated liposomes. At pH 7.4, the mPEG(5) (kDa)-SDM8-coated liposomes undergo low cell association while remarkable cell association occurred at pH 6.5, which allowed for the controlled intracellular delivery of model macromolecules and small molecules loaded in the liposome under tumor conditions.Peer reviewe

Cytotoxicity of a mitochondriotropic quercetin derivative: Mechanisms

AbstractThe mitochondriotropic compound 7-O-(4-triphenylphosphoniumbutyl)quercetin iodide (Q-7BTPI) in the μM concentration range caused necrotic death of cultured cells by acting as a prooxidant, with generation of superoxide anion in the mitochondria. Externally added membrane-permeating superoxide dismutase or catalase largely prevented death. Rescue by permeant catalase indicates that the toxicant is H2O2, or reactive species derived from it. Rescue by permeant dismutase suggests the possibility of a chain mechanism of H2O2 production, in which dismutation of superoxide constitutes a termination step. Oxidative stress was due to the presence of free phenolic hydroxyls and to accumulation in mitochondria, since the analogous mitochondriotropic per-O-methylated compound -3,3′,4′,5-tetra-O-methyl,7-O-(4-triphenylphosphoniumbutyl) quercetin iodide (QTM-7BTPI)—or Quercetin itself induced no or little superoxide production and cell death. Q-7BTPI did not cause a significant perturbation of the mitochondrial transmembrane potential or of respiration in cells. On the other hand its presence led to inhibition of glutathione peroxidase, an effect expected to accentuate oxidative stress by interfering with the elimination of H2O2. An exogenous permeable glutathione precursor determined a strong increase of cellular glutathione levels but did not rescue the cells. Death induction was selective for fast-growing C-26 tumoral cells and mouse embryonic fibroblasts (MEFs) while sparing slow-growing MEFs. This suggests a possible use of Q-7BTPI as a chemotherapeutic agent