Thermochemistry of the E-ALD process for the growth of Cu x Zn y S on Ag(111): Interpretation of experimental data

The electrochemical atomic layer deposition (E-ALD) growth of chalcogenides materials enables the deposition of technologically interesting ultra-thin films. However, this method raises some questions about the actual growth mechanism. We addressed one of the more interesting anomalies reported lately: the occurrence of the Zn-deficiency and of the polycrystalline thread-like overgrown structures in the E-ALD growth of CuxZnyS. The present study was developed using a computational speciation approach under the mass balance method. Exploiting a well-established computational approach, but uncommonly applied to the electrochemical science, we calculated the predominance charts and the equilibrium speciation of the solid phases during the electrochemical process. On this basis, we obtained a deep insight into the mechanism underlying the E-ALD process from a thermodynamic standpoint. Thus, we identified the crucial steps of the CuxZnyS growth leading to the anomalies object of this research

Osteoporosis, inflammation and ageing

Osteoporosis is a condition characterized by low bone mass and increased bone fragility, putting patients at risk of fractures, which are major causes of morbidity substantially in older people. Osteoporosis is currently attributed to various endocrine, metabolic and mechanical factors. However, emerging clinical and molecular evidence suggests that inflammation also exerts significant influence on bone turnover, inducing osteoporosis. Numerous proinflammatory cytokines have been implicated in the regulation of osteoblasts and osteoclasts, and a shift towards an activated immune profile has been hypothesized as important risk factor. Chronic inflammation and the immune system remodelling characteristic of ageing, as well as of other pathological conditions commonly associated with osteoporosis, may be determinant pathogenetic factors. The present article will review the current perspectives on the interaction between bone and immune system in the elderly, providing an interpretation of osteoporosis in the light of inflamm-ageing

Genetic Algorithm for the optimal placement of Self-Centering Damage-Free joints in steel MRFs

Nowadays' earthquake engineering is coping with the challenging task of providing low-cost seismic resilient structures. Among others, a viable solution for seismic resilient Steel Moment Resisting Frames (MRFs) is based on the use of Self-Centering Damage-Free (SCDF) joints at Column Bases (CBs) and Beam-to-Column Joints (BCJs), ensuring both the energy dissipation capacity and self-centering behavior of the structure. Past studies demonstrated the beneficial effects gained in damage and residual drifts reduction by including SCDF joints at all BCJs and CBs. However, this solution leads to the highest structural complexity, limiting the practical application. Significant improvements can be obtained including a limited number of SCDF BCJs, but there is a lack of generalized recommendations on the number required and their effective placement. In this work, a Genetic Algorithm (GA) is proposed to define the optimal placement of SCDF BCJs in steel MRFs. The GA is implemented in Matlab, and non-linear time-history analyses are performed in OpenSees to calculate the Fitness-Function. The results of the GA are validated against a Brute-Force Approach. An 8-story 3-bays steel MRF and a type of SCDF joint are selected for case study purposes, non-linear Finite Element Models are developed in OpenSees, and the GA is applied. The results show that the proposed GA is an efficient methodology to solve the considered optimization problem

Polyhedral separation via difference of convex (DC) programming

We consider polyhedral separation of sets as a possible tool in supervised classification. In particular, we focus on the optimization model introduced by Astorino and Gaudioso (J Optim Theory Appl 112(2):265–293, 2002) and adopt its reformulation in difference of convex (DC) form. We tackle the problem by adapting the algorithm for DC programming known as DCA. We present the results of the implementation of DCA on a number of benchmark classification datasets

Comparative effects between electronic cigarette and tobacco cigarette smoke on oxidative markers in cultured immune cells isolated from rats.

Background. Tabaco cigarette smoke (TCS) was previously demonstrated to affect the innate and adaptive immune responses as a consequence of oxidant generation which play a pivotal role in neutrophilic airway inflammation. Aim of this paper was to investigate whether electronic-cigarette smoke (ECS) generates reactive oxygen species (ROS) similarly to cigarette smoke. Method. By means of a house made apparatus, ECS and TCS were collected in FBS which was used to grow immune cells isolated from rats. As index of oxidative products nitrite and thiobarbituric acid-reactive substances (TBARS) were determined in the medium before and after cell growth. Results. The results showed that  i) ECS caused a remarkable increase of nitrites and TBARS although in lesser extension than TCS, ii) the cells grown in ECS and TCS-exposed medium were able to reduce TBARS but not nitrites present in the medium, iii) while all 3 kinds of cells in ECS- exposed medium gave the same levels of ROS, PBMC in TCS-exposed medium were able to reduce nitrites and TBARS more efficiently than spleen and lymph node cells, iiii) TCS and ECS not influence the PBMC and spleen T cell subtype populations (CD4+, CD8+). Conclusions. As ECS nicotine-free gave the same results of unexposed medium, we could conclude that the increase of ROS in ECS exposed medium was prevalently due to nicotine

A study on occupational exposure of Sicilian farmers to Giardia and Cryptosporidium

Introduction. A cross-sectional study was undertaken to deter- mine the prevalence of Giardia and Cryptosporidium in calves of Palermo area (Sicily) and to evaluate the occupational risk associated with occurrence of zoonotic genotypes. Methods. A total of 217 faecal samples, from 149 calves (between 2 and 240 days of age) and 68 farmers, were collected in 19 cattle- farms of Palermo area. A questionnaire regarding demographic characteristics and personal hygienic measures was submitted to all farmers. All faecal samples were analyzed by Immunoflu- orescence assay and Polimerase Chain Reaction (PCR); geno- types were determined by DNA sequencing of Triose Phosphate Isomerase gene for Giardia and Small Subunit Ribosomal RNA gene for Cryptosporidium. Results. None farmer tested was positive for Giardia and Cryptosporidium, whereas these protozoa were respectively detected in 53 (including 5 with zoonotic G. duodenalis geno- type A) and 17 (of which 1 with zoonotic C. ubiquitum) of the examined calves. Discussion. The results indicate that the risk of transmitting both protozoa to farmers in Palermo area is negligible although it can- not be considered null because of identification of human geno- types/species in calves

Computational Speciation Models: A Tool for the Interpretation of Spectroelectrochemistry for Catalytic Layers under Operative Conditions

none7In this study,the first coupled FEXRAV and chemical speciation modelling study of the Pd deactivation is presented. Due to the high brilliance of synchrotron light, FEXRAV can investigat edeeply buried surfaces. More specifically, we directly analyzed the evolution of the Pd/C catalytic layer during a voltammetric cycle, through a specifically designed electrochemical cell. Still, we observed a complex interfacial chemistry of Pd, which impairs a straightforward interpretation of FEXRAV data. Exploiting thermodynamic chemical speciation modelling we were able to overcome this issue. The study leads to three main results: 1) the confirmation of the relationship between the change of the Pd/Pd(II) ratio and the change of the Fluorescence intensity 2) the investigation of the deactivation mechanism 3)the identification of the relevant species leading to the electrodissolution of Pd under operative conditions. This study opens new perspectives for the application of the chemical speciation modelling to the study of the deactivation mechanism of Pd in Pd/C catalytic layers under operative conditions in different electrolytes.mixedMontegrossi, G.; GIACCHERINI, ANDREA; BERRETTI, ENRICO; DI BENEDETTO, FRANCESCO; INNOCENTI, MASSIMO; D'Acapito, F.; LAVACCHI, ALESSANDROMontegrossi, G.; Giaccherini, Andrea; Berretti, Enrico; DI BENEDETTO, Francesco; Innocenti, Massimo; D'Acapito, F.; Lavacchi, Alessandr

Road tunnel risk-based safety design methodology by GU@LARP Quantum risk model

The ALARP concept is used in different countries for different sectors of activity where a risk assessment or measure is requested. In this paper a model is developed based upon ALARP principle for tunnel risk-based design in case of fire accident scenarios. In Italy, ALARP risk acceptability and tolerability criteria have been adopted then the compliance with them has to be verified in order to guarantee a minimum-sufficient level of safety. The quantum of risk coupled with any design scenario is defined and modelled and the consequent individual quantum of risk coupled with the single exposed unit in the scenario is defined too. The methodologies for the identification of the requested design scenario, in number and type, are outlined. The scenarios are described in a shape suitable as INPUTS in the thermo-dynamical numerical simulations for fire generation and exposed units evacuation. The expected OUTPUTS of the numerical simulation are the estimations of the number of the fatalities (N) coupled with the single specific scenarios. In parallel with the above physical deterministic scenario simulations, a conceptual and operational procedure has been also established for the scenarios probabilities assessment. Merging the resulting data of both the above separate models, the risk quanta Gu@larp model is finally established. A case study is developed considering scenarios related to a virtual limit tunnel to support the description of the model itself, properties, advantages and perspectives

Ottimizzazione del posizionamento di nodi ricentranti in telai momento resistenti in acciaio tramite un algoritmo genetico = Optimal Placement of Self-Centering Joints in Steel Moment Resisting Frames Through a Genetic Algorithm

Nowadays’ earthquake engineering is coping with the challenging task of providing low-cost seismic resilient structures. For Steel Moment Resisting Frames (MRFs) a viable solution is to use Self-Centering Damage-Free (SCDF) devices at Column Bases (CBs) and Beam-to-Column Joints (BCJs), ensuring both the energy dissipation capacity and the self-centering behavior of the structure. Past studies demonstrated the beneficial effects gained in damage and residual drifts reduction through the use of SCDF devices in all BCJs and CBs. However, this solution leads to the highest structural complexity and cost, limiting the practical application of these systems. Significant improvements can be obtained including a limited number of SCDF BCJs, but there is a lack of generalized recommendations on the number required and the effective placement. In this work, a Genetic Algorithm (GA) is proposed to define the optimal placement of a limited number of SCDF BCJs in steel MRFs. The GA is implemented in Matlab, and Non-Linear Time-History Analyses are performed in OpenSees to calculate the Fitness-Function based on residual drifts. An 8-story 3-bays steel MRF and a type of SCDF device are selected as case study and non linear Finite Element Models (FEM) are developed in OpenSees. The GA is applied assuming 16 SCDF BCJs and it is validated through a Brute Force approach. The results show that the proposed GA is an efficient methodology to solve the considered optimization problem. // Uno degli obiettivi principali dell'ingegneria sismica odierna è quello di progettare strutture sismo-resilienti a basso costo e tali da poter essere ampiamente utilizzate su larga scala. Per i telai momento resistenti in acciaio (MRFs), una possibile soluzione consiste nell'utilizzo di dispositivi dissipativi-ricentranti (SCDF) nei nodi trave-colonna (BCJs) e nodi di base (CBs) in modo da garantire sia la capacità dissipativa che il comportamento ricentrante della struttura. È stato dimostrato che l'uso di tali dispositivi in tutti i BCJs e CBs ha effetti benefici nella riduzione dei danni e degli spostamenti residui. Tuttavia, tale soluzione incrementa complessità e costo strutturale, limitando l'applicazione di questi sistemi nella pratica progettuale. Al fine di raggiungere un compromesso, studi precedenti hanno investigato l’utilizzo di un numero limitato di SCDF BCJs dimostrando che tali soluzioni possono fornire miglioramenti significativi in termini di prestazione sismica mantenedo una complessità ridotta. Tuttavia non ci sono ancora raccomandazioni generalizzate rispetto al numero di dispositivi necessario e al loro efficace posizionamento. In questo studio, viene proposto un Algoritmo Genetico (GA) per definire il posizionamento ottimale di un numero limitato di SCDF BCJs in MRFs in acciaio. Il GA è implementato in Matlab ed analisi dinamiche non lineari sono eseguite in OpenSees per calcolare la Fitness-Function basata sui drifts residui. Un MRF in acciaio con 8 piani e 3 campate e un tipo di dispositivo SCDF sono considerati per la definizione di un caso studio. Il GA è applicato assumendo 16 SCDF BCJs e validato rispetto un approccio Brute Force. I risultati mostrano che il GA proposto è una metodologia efficiente per risolvere il problema di ottimizzazione considerato

E-ALD: Tailoring the Optoeletronic Properties of Metal Chalcogenides on Ag Single Crystals

Technological development in nanoelectronics and solar energy devices demands nanostructured surfaces with controlled geometries and composition. Electrochemical atomic layer deposition (E-ALD) is recognized as a valid alternative to vacuum and chemical bath depositions in terms of growth control, quality and performance of semiconducting systems, such as single 2D semiconductors and multilayered materials. This chapter is specific to the E-ALD of metal chalcogenides on Ag single crystals and highlights the electrochemistry for the layer-by-layer deposition of thin films through surface limited reactions (SLRs). Also discussed herein is the theoretical framework of the under potential deposition (UPD), whose thermodynamic treatment open questions to the correct interpretation of the experimental data. Careful design of the E-ALD process allows fine control over both thickness and composition of the deposited layers, thus tailoring the optoelectronic properties of semiconductor compounds. Specifically, the possibility to tune the band gap by varying either the number of deposition cycles or the growth sequence of ternary compounds paves the way toward the formation of advanced photovoltaic materials