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In many fields, it is a common practice to collect large amounts of data characterized by a high number of features. These datasets are at the core of modern applications of supervised machine learning, where the goal is to create an automatic classifier for newly presented data. However, it is well known that the presence of irrelevant features in a dataset can make the learning phase harder and, most importantly, can lead to suboptimal classifiers. Consequently, it is becoming increasingly important to be able to select the right subset of features. Traditionally, optimization metaheuristics have been used with success in the task of feature selection. However, many of the approaches presented in the literature are not applicable to datasets with thousands of features because of the poor scalability of optimization algorithms. In this article, we address the problem using a cooperative coevolutionary approach based on differential evolution. In the proposed algorithm, parallelized for execution on shared-memory architectures, a suitable strategy for reducing the dimensionality of the search space and adjusting the population size during the optimization results in significant performance improvements. A numerical investigation on some high-dimensional and medium-dimensional datasets shows that, in most cases, the proposed approach can achieve higher classification performance than other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The deactivation pattern of a "model" Ni/MgO catalyst in the pre-reforming of n-hexane with steam (T, 450 °C; P, 5-15 bar) is reviewed. The influence of the steam-to-carbon ratio (S/C, 1.5-3.5) on the rate of catalyst fouling by coking is ascertained. Catalyst fouling leads to an exponential decay in activity, denoting 1st-order dependence of the coking process on active sites availability. Hydrogen hinders the coking process, though slight activity decay is due to sintering of the active Ni phase. Deactivation by thiophene causes a sharp, almost linear, drop to nearly zero activity within only 6 h; this deactivation is likely due to dissociative adsorption of thiophene with subsequent strong, irreversible chemical adsorption of S-atoms on active Ni sites, i.e., irreversible poisoning. Modeling of activity decay curves (α, at/a0) by proper kinetic equations allows assessing the effects of temperature, pressure, S/C, H2 and thiophene feed on the deactivation pattern of the model Ni/MgO catalyst by coking, sintering, and poisoning phenomena. [ABSTRACT FROM AUTHOR]

Batch sorption experiments using a starch-based sorbent were carried out for the removal of heavy metals present in industrial water discharges. The influence of contact time, mass of sorbent and pollutant load was investigated. Pollutant removal was dependent on the mass of sorbent and contact time, but independent of the contaminant load. The process was uniform, rapid and efficient. Sorption reached equilibrium in 60 min irrespective of the metal considered (e.g. Zn, Pb, Cu, Ni, Fe and Cd), reducing concentrations below those permitted by law. The material also removed residual turbidity and led to a significant decrease in the residual chemical oxygen demand (COD) present in the industrial water discharge. The germination success of lettuce (Lactuca sativa) was used as a laboratory indicator of phytotoxicity. The results show that the sorption using a starch-based sorbent as non-conventional material, is a viable alternative for treating industrial wastewaters. [Copyright &y& Elsevier]

Abstract: A class of MnCeO x catalysts has been synthesized via the new redox-precipitation route in alternative to the conventional co-precipitation technique. The effects of preparation method, composition and calcination temperature on catalyst texture, dispersion and reduction pattern properties have been addressed. Redox-precipitated systems exhibit high surface area (SA, 120–170m2/g), large pore volume (PV, 0.4–0.5cm3/g) and a “narrow” pore size distribution (PSD) in a wide range of the Mn/Ce ratio (1/3–3/1). A quasi-molecular dispersion markedly improves oxide-support interactions and reducibility of the active phase. Redox-precipitated systems show a superior performance in the catalytic wet oxidation of phenol with oxygen (CWAO) at 373K in terms of substrate and total organic carbon (TOC) elimination and mineralization (i.e., CO2 formation) selectivity. Carbon mass-balance from TG-DSC data of used catalysts and CO2 selectivity values signal that the CWAO of phenol proceeds via a L–H reaction path, the oxidation of C-containing species being the rate limiting step (r.l.s.). Then, an optimum average pore diameter (APD, 10–15nm) enhances the rate of the adsorption step, while a straight relation between CO2 selectivity and reducibility prove that dispersion and redox properties of the active phase control the mineralization activity of the MnCeO x system. [Copyright &y& Elsevier]

Abstract: A new synthesis route driving redox-precipitation reactions among MnVII, CeIII and MnII precursors in basic aqueous solution yields MnCeO x catalysts (Mn loading, 9–33wt%) with improved textural and structural properties in comparison to the conventional co-precipitation technique. Irrespective of the Mn loading, BET, X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) findings prove that the new method ensures a very high reproducibility in all the main physico-chemical properties of MnCeO x catalysts. Enabling a monolayer dispersion of the active phase, the “redox-precipitation” method greatly promotes the reducibility and the surface affinity of the MnCeO x system towards gas-phase oxygen. [Copyright &y& Elsevier]

The planning process is a multiactor, multilevel process, and the techniques we need for it must be suitable for all the protagonists involved. Moreover, the difficulty in dealing with the complexity of urban systems and the related difficulty of analyzing and forecasting are twofold: one kind of difficulty lies in the complexity of the system itself, and the other is due to the actions of actors, which are "acts of freedom." Correspondingly, the process of urban planning requires a set of techniques and models that have proved to be of great potential for management of communication, participation, consensus-building and system' simulation. In this paper, we describe the peculiarity of the articulated set of tools that should be used to support planning, allowing the setting up and management of processes of participation and communication tailored to the needs of specific projects — a set of friendly tools that make the relationship between technicians, clients and users effective and efficacious. Following this discussion we present a very flexible software environment based on cellular automata (Cellular Automata General Environment — CAGE) that can be used to simulate planning decisions and can be coupled with other modules dealing with the "social side" of complexity. [ABSTRACT FROM AUTHOR]

Abstract: The atmospheric oxidation of mercury in the Mediterranean marine boundary layer (MBL) has been studied using the Atmospheric Mercury Chemistry over the Sea (AMCOTS) model. The model results have been compared to measured data obtained during an oceanographic research campaign in 2000, with more success than previous modelling attempts. In light of the often high concentrations of ozone present in the Mediterranean boundary layer, seasonal case studies using typical meteorological conditions and average ozone concentrations have been performed to identify the main oxidants of elemental mercury. The sensitivity of the modelled reactive gaseous mercury (RGM) concentrations to the Hg+O3 rate constant has been assessed using the two most recent rate determinations. The results using the higher of the two literature values gives results inconsistent with measured values of RGM when the reaction between Hg and O3 is assumed to give a gas phase product. This does not necessarily indicate that the rate constant is incorrect but possibly that other rate constants in the model are overestimated or indeed that there may be reduction reactions occurring in the atmosphere which have yet to be identified. Alternatively, when the reaction product of Hg and O3 is assumed to be a solid and therefore not contribute to RGM the modelled and measured results are comparable. The deposition rates calculated by the model when compared with calculated and measured sea surface emission fluxes available in the literature indicate that dry deposition flux of RGM is comparable to the sea surface emission flux. The calculated lifetime of Hg0 in the Mediterranean MBL is between one and two weeks. [Copyright &y& Elsevier]

The activity–stability pattern of a 19 wt.% Ni/MgO catalyst in the pre-reforming (T, 450 °C; P, 10 bar) of n-hexane with steam (S/C, 1.5–3.5) in absence and presence of H2 (H/C, 2) has been investigated. Deactivation profiles of the kinetics of CH4 and CO/CO2 formation indicate that the activity, selectivity and stability are closely related. Hydrogenation of carbon species to methane is a critical step involving the occurrence of coking in the pre-reforming of hexane. Thermodynamic analysis of the outlet reaction stream signals that the net coking rate depends upon the relative kinetics of carbon methanation (MET, C+2H2⇄CH4) and gasification/water–gas-shift (GAS, C+H2O⇄H2+CO; WGS, CO+H2O⇄CO2+H2) reactions, while negligible appears the contribution of the Bouduard reaction path (DISP, 2CO⇄C+CO2). [Copyright &y& Elsevier]

This study presents an application that estimates all possible paths within an urban environment and proposes the optimal one according to objective criteria and individualized options. The application grounds its functionality on a Cellular Automaton (CA) that models the area of interest and provides the rule that activates the processing of input data. The model incorporates the term walkability as a discrete magnitude that integrates qualitative features of pedestrian mobility. The proposed application fosters sustainable forms of movement at a local level that undoubtedly improves the human physical status and upgrades civilian living conditions. In the context of this paper, we provide a thorough description of the operational principles of the model, and we test its validity by applying it in Xanthi, a medium size city located in northeastern Greece. Finally, we describe variants of the initial scenario to demonstrate the sensibility of the model in external assessments as well as its resilience in biasing manipulations. [ABSTRACT FROM AUTHOR]

Evidence exists that the gut microbiota contributes to the alterations of lipid metabolism associated with high-fat diet (HFD). Moreover, the gut microbiota has been found to modulate the metabolism and absorption of dietary lipids, thereby affecting the formation of lipoproteins occurring at the intestinal level as well as systemically, though the pathophysiological implication of altered microbiota composition in HFD and its role in the development of atherosclerotic vascular disease (ATVD) remain to be better clarified. Recently, evidence has been collected indicating that supplementation with natural polyphenols and fibres accounts for an improvement of HFD-associated intestinal dysbiosis, thereby leading to improved lipidaemic profile. This study aimed to investigate the protective effect of a bergamot polyphenolic extract (BPE) containing 48% polyphenols enriched with albedo and pulp-derived micronized fibres (BMF) in the gut microbiota of HFD-induced dyslipidaemia. In particular, rats that received an HFD over a period of four consecutive weeks showed a significant increase in plasma cholesterol, triglycerides and plasma glucose compared to a normal-fat diet (NFD) group. This effect was accompanied by body weight increase and alteration of lipoprotein size and concentration, followed by high levels of MDA, a biomarker of lipid peroxidation. Treatment with a combination of BPE plus BMF (50/50%) resulted in a significant reduction in alterations of the metabolic parameters found in HFD-fed rats, an effect associated with increased size of lipoproteins. Furthermore, the effect of BPE plus BMF treatment on metabolic balance and lipoprotein size re-arrangement was associated with reduced gut-derived lipopolysaccharide (LPS) levels, an effect subsequent to improved gut microbiota as expressed by modulation of the Gram-negative bacteria Proteobacteria, as well as Firmicutes and Bacteroidetes. This study suggests that nutraceutical supplementation of HFD-fed rats with BPE and BMP or with their combination product leads to restored gut microbiota, an effect associated with lipoprotein size re-arrangement and better lipidaemic and metabolic profiles. [ABSTRACT FROM AUTHOR]

The surface acidic properties of oxide catalysts and carriers (γ-Al 2 O 3 , CeO 2 , ZrO 2 , SiO 2 , TiO 2 , HZSM5 zeolite) have been comparatively probed by ammonia temperature programmed desorption (ATPD) measurements. Reliability and accuracy of ATPD data were assessed by theoretical criteria and experimental tests highlighting the effects of carrier gas, data acquisition mode, catalyst particle size and reactor geometry. All the materials feature complex ATPD patterns spanned in the range 423–873 K, except for ceria showing a narrow and resolved desorption peak, indicative of homogeneous weak acidity. Quantitative data signal a difference of more than one order of magnitude in ammonia uptake between silica and the other materials. Since the ATPD profiles of ceria match Gaussian curves regardless of heating rate and surface coverage, the patterns of the studied materials are described as linear combinations of four Gaussian functions related to weak, medium, strong and very strong site populations. ATPD modelling analyses to get energy data are discussed. The functionality of the studied materials in the dehydration of isopropanol to propylene matches abundance, type and strength of surface acid sites. [ABSTRACT FROM AUTHOR]

The objective of this computational study was to investigate to which extent theavailabilityand theway of useof historical maps may affect the quality of the calibration process of cellular automata (CA) urban models. The numerical experiments are based on a constrained CA applied to a case study. Since the model depends on a large number of parameters, we optimize the CA using cooperative coevolutionary particle swarms, which is an approach known for its ability to operate effectively in search spaces with a high number of dimensions. To cope with the relevant computational cost related to the high number of CA simulations required by our study, we use a parallelized CA model that takes advantage of the computing power of graphics processing units. The study has shown that the accuracy of simulations can be significantly influenced by both the number and position in time of the historical maps involved in the calibration. [ABSTRACT FROM AUTHOR]

We propose an operational approach to incorporate complex urban geography into urban land-use cellular automata (CA) models. The local interactions in the standard urban CA models are habitually based on the 'as the crow flies' spatial distances among cells. This is hardly a plausible assumption if the local interactions and influences among places are to depend on their mutual proximity in terms of accessibility to humans, shaped among others by the network of transportation and pedestrian networks. Very little operational efforts have been undertaken in CA-based urban modelling to investigate and provide a more coherent treatment of such irregular proximities. In this paper, as a contribution in that direction, we lay down a possible CA modelling approach, discuss a few toy examples and present an application on the city of Heraklion in Crete. [ABSTRACT FROM AUTHOR]

The accuracy of most Cellular Automata (CA) models for simulating wildfires is limited by the fact that spread directions are constrained to the few angles imposed by the regular lattice of cells. To mitigate such problem, this paper proposes a new CA in which a local randomization of the spread directions is introduced. The suggested technique, inspired by a method already used for simulating lava flows, is empirically investigated under homogeneous conditions and by comparison with the wildfire simulator FARSITE. According to the presented results, the adopted randomization can significantly improve the accuracy of fire spread simulations based on a standard center-to-center ignition scheme. [ABSTRACT FROM AUTHOR]

In recent years, urban models based on Cellular Automata (CA) are becoming increasingly sophisticated and are being applied to real-world problems covering large geographical areas. As a result, they often require extended computing times. However, in spite of the improved availability of parallel computing facilities, the applications in the field of urban and regional dynamics are almost always based on sequential algorithms. This paper makes a contribution toward a wider use in the field of geosimulation of high performance computing techniques based on General-Purpose computing on Graphics Processing Units (GPGPU). In particular, we investigate the parallel speedup achieved by applying GPGPU to a popular constrained urban CA model. The major contribution of this work is in the specific modeling we propose to achieve significant gains in computing time, while maintaining the most relevant features of the traditional sequential model. [ABSTRACT FROM AUTHOR]

Abstract: The effects of the preparation method (deposition–precipitation, co-precipitation, incipient-wetness, combustion) and loading (1–5wt.%) on the structure and redox features of the Au/CeO2 system have been probed by XRD, TEM and TPR techniques. The catalytic pattern in total (TOX) and preferential (PROX) CO oxidation has been assessed by temperature programmed reaction tests in the range 273–473K. Controlling surface area and residual chlorine, the synthesis route determines the strength of the Au–CeO2 interaction which, reflecting in a hard reduction of the active phase, hinders the CO oxidation functionality. Chlorine removal by washing treatment in diluted alkaline solutions enables an easy reduction of the active phase, levelling off the TOX and PROX performance of the various systems. [Copyright &y& Elsevier]

The kinetics of the CO oxidation on a typical nanocomposite MnCeO x catalyst (M5C1) were probed by temperature programmed catalytic reaction (TPCR) tests in the range of 293–533 K, varying reagent partial pressure ( i.e. , p CO and p O2 ) between 0.00625 and 0.025 atm (P, 1 atm) (Arena et al., 2017). Experimental data indicate kinetic orders of 0.6 and 0.4 on p CO and p O2 respectively, with apparent activation energy of 40 ± 3 kJ/mol (Arena et al., 2017). A systematic study of the interaction pattern of catalyst with reagent and product molecules shows easy reactivity of surface oxygen to CO, low mobility of lattice oxygen and weak surface affinity to CO 2 . Systematic evidences on reaction mechanism and surface intermediates signal an extrafacial redox path, triggered by abstraction of oxygen atoms in the neighbouring of active Mn IV sites (Arena et al., 2017), and sustained by O 2 species adsorbed on those surface oxygen vacancies. A Langmuir-Hinshelwood (L-H) reaction mechanism leads to a formal kinetic model explaining the CO oxidation functionality of bare and promoted MnO x catalysts. [ABSTRACT FROM AUTHOR]

We present a methodology and a planning and design support software tool for evaluating walkability and pedestrian accessibility of places which are relevant for people’s capabilities, and thus an important component of quality of life in cities. A multicriteria evaluation model, at the core of the decision support system, is used to assign walkability scores to points in urban space. Walkability scores are obtained through algorithms which process spatial data and run the evaluation model in order to derive potential pedestrian routes along the street network, taking into account the quality of urban space on several attributes relevant for walkability. One of its notable characteristics is a certain reversal of perspective in evaluating walkability: the walkability score of a place does not reflect how that place isper sewalkable, but instead how and where to can one walk from there, that is to say, what is the walkability the place is endowed with. This evaluation incorporates three intertwined elements: the number of destinations/opportunities reachable by foot, their walking distances, and the quality of the paths to these destinations. In this article, we furthermore demonstrate possible uses of the support system by reporting and discussing the results of a case-study assessment of a project for the Lisbon’sSegunda Circular(Second Ring Road). The software tool is made freely available for download. [ABSTRACT FROM PUBLISHER]

The pressing need to prevent further damages to environment and deterioration of natural resources urges a global effort to shift from the current money-making industrial policies to a sustainable development pattern. This requires an easy availability of handy and economical technologies for depollution of gas and liquid wastes, “green” industrial manufacturing processes and “zero-emission” energy supply systems. In this context the purification and reuse of industrial wastewaters represents a very critical environmental issue because of the global freshwater shortage, the continuing water resources depletion, and the increasing pollutants release. In this context, the heterogeneous catalytic wet air oxidation (CWAO) is nowadays considered the most promising technology for large-scale application to detoxification of noxious wastewaters, provided that robust, effective and cost-effective catalysts are available. Then, this work provides an overview of mechanistic and kinetic issues of the homogeneous and heterogeneous CWAO of several classes of industrial pollutants, at basis of recent advances on design and development of supported noble metal and oxide catalysts. [ABSTRACT FROM AUTHOR]

Patterns of urban development influence flows of material and energy within urban settlements and exchanges with its surrounding. In recent years the quantitative estimation of the components of the so-called urban metabolism has increasingly attracted the attention of researchers from different fields. To contribute to this effort we developed a modelling framework for estimating the carbon exchanges together with sensible and latent heat fluxes and air temperature in relation to alternative land-use scenarios. The framework bundles three components: (i) a Cellular Automata model for the simulation of the urban land-use dynamics; (ii) a transportation model for estimating the variation of the transportation network load and (iii) the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA) model tightly coupled with the mesoscale weather forecasting model WRF. We present and discuss the results of an example application on the City of Florence. [ABSTRACT FROM AUTHOR]

Highlights: [•] The activity of MnCeO x catalyst in the wet air oxidation of toxic and refractory pollutants is assessed. [•] The CWAO of phenol and C1-C2 acids proceeds via a Langmuir–Hinshelwood reaction path. [•] The removal efficiency of phenol and C1-C2 acids depends on different adsorption mechanisms. [•] Surface oxidation is the rate determining step of the CWAO of phenol. [•] The CWAO of C1-C2 acids implies comparable rates of surface adsorption and oxidation steps. [ABSTRACT FROM AUTHOR]

Abstract: In the field of wildfire risk management the so-called burn probability maps (BPMs) are increasingly used with the aim of estimating the probability of each point of a landscape to be burned under certain environmental conditions. Such BPMs are usually computed through the explicit simulation of thousands of fires using fast and accurate models. However, even adopting the most optimized algorithms, the building of simulation-based BPMs for large areas results in a highly intensive computational process that makes mandatory the use of high performance computing. In this paper, General-Purpose Computation with Graphics Processing Units (GPGPU) is applied, in conjunction with a wildfire simulation model based on the Cellular Automata approach, to the process of BPM building. Using three different GPGPU devices, the paper illustrates several implementation strategies to speedup the overall mapping process and discusses some numerical results obtained on a real landscape. [Copyright &y& Elsevier]

Abstract: Physicochemical properties and CO2-to-methanol hydrogenation functionality (T R, 453–513K; P R, 0.1–5.0MPa) of Al2O3-, ZrO2-, and CeO2-supported Cu–ZnO catalysts are systematically addressed. Carriers control texture and metal surface exposure (MSA), while characterization of steady-state catalysts shows extensive CO2 and H2 coverage regardless of MSA, proving a crucial influence of the oxide carrier on the adsorption properties of the Cu–ZnO system. The kinetic dependence on p CO2 and p H2 confirms that dioxo-methylene intermediate hydrogenation is the rate-determining step (r.d.s.) at P <0.1MPa, while a low kinetic dependence on pressure (0.3–0.5) signals that product desorption is the r.d.s. at P >0.1MPa. The influence of flow rate on selectivity pattern discloses that CH3OH is the primary reaction product at T <473K, while at higher temperatures, CO forms by consecutive decomposition of methanol (MD) and parallel reverse water–gas shift (RWGS). Textural and chemical effects of the zirconia carrier confer superior performance on the Cu–ZnO/ZrO2 system, attaining a space time yield (STY) of 1.2 at 10% conversion per pass. [Copyright &y& Elsevier]

A hybrid technique based on Cellular Automata and Genetic Algorithms has been used for modeling lava flows on Mt Etna volcano (Italy). In particular, a Parallel Master-Slave Genetic Algorithm has been applied to evolve a two dimensional Cellular Automatamodel for "aa"-type lava flows, typical of the considered study area. Specifically, the 2001 Etnean Nicolosi case study has been considered for model calibration, while a subsequent validation phase has been performed by considering further events occurred in the same area. Results have confirmed both the goodness of the cellular automata simulation model and of the genetic algorithm employed for its calibration. An application concerning hazard evaluation has been subsequently performed on a vast area of the volcano, regarding different types of vulnerability assessments. Results have pointed out the validity of the methodology and its usefulness for Civil Defence purposes. [ABSTRACT FROM AUTHOR]

Abstract: Cellular automata are widely utilized for modelling and simulating complex dynamical systems whose evolution depends on the local interactions of their constituent parts. Simulation by Cellular Interactive Automata of the Rheology of Aetnean lava flows (SCIARA) is a Cellular Automata model for simulating lava flows; its release γ2 introduces innovations to the empirical method for modelling macroscopic phenomena that was utilized in the previous releases. The lava flows are described as “blocks”, individuated by their barycentre co-ordinates and velocities. This approach is different from the previous releases of SCIARA and from cellular automata derived models for fluid-dynamical phenomena such as lattice-gas and lattice-Boltzmann models. Block specifications permit to obtain a more physical description of the phenomenon and a more accurate control of its development. SCIARA γ2 was applied to the 2002 Etnean lava flows with satisfying results, obtaining better simulations in comparison with the previous releases. [Copyright &y& Elsevier]

The working mechanism of a ceria-supported Cu (Cuat:Ceat = 1:10) system in the Catalytic Wet Oxidation (CWO) of phenol with O2 ( T R, 130–170 °C; P O 2, 7 atm) has been thoroughly assessed. Basic relationships amongst pH, extent of leaching and rate of phenol and TOC conversion prove the major contribution of a homogeneous catalytic path by Cu ions on the peculiar CWO pattern of supported copper catalyst. In addition, gas-phase reduction/oxidation tests signal the lack of reversibility of the redox cycle of the CuCeO x system under typical reaction conditions. [ABSTRACT FROM AUTHOR]