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A detailed experimental characterization of the particle emissions of a EURO 5 light-duty Diesel engine, equipped with a wall flow Diesel Particulate Filter (DPF), is presented. Particle Size Distributions (PSDs) in the range from 4.5 up to 160 nm have been measured at the engine exhaust by means of a Scanning Mobility Particle Sizer, during both DPF accumulation and regeneration phase. During accumulation, the size-dependent DPF removal efficiency has been evaluated by PSDs measurements at both inlet and outlet of the filter. The maximum efficiency was found in the range 10-40 nm. Nevertheless, the DPF ensures a strong reduction in the emissions for the sub-23 nm nanoparticles too, with an efficiency between 91–95%. Unless for the warm-up phase, the engine operating conditions do not have a great impact on the particles emitted due to the high DPF removal efficiency. The measurements carried out during the regeneration phase evidenced that particle emissions strongly depend on DPF temperature. Actually, once the soot burnout temperature is reached, soot oxidation starts and a great amount of particles in terms of PN is released. Overall, PSDs showed an increase in particle number concentration up to two order of magnitude with respect to the emissions measured during the accumulation phase. [ABSTRACT FROM AUTHOR]

Flame synthesis of Carbon NanoParticle (CNP) films is gaining strong interest for novel industrial applications because of the easy tuning of the operating conditions that enables accurate control of the chemical and physical properties of the produced CNPs. This work proposes a novelty in the synthesis of CNP films, namely the possibility of applying electric fields in flame to trigger electrophoretic deposition phenomena. In this way, it is possible to add another degree of freedom to the harvesting process and potentially modify the properties of the CNP films, without changing the operating flame conditions. To investigate the physical mechanisms governing the thermo-electrophoretic deposition of CNPs, a numerical model to simulate the particle dynamics close to the collecting substrate has been developed, and experiments have been carried out to provide highly controlled test conditions that can be used to support model validation. The experimental results consist of Atomic Force Microscopy (AFM) measurements to determine the number of particles deposited after a controlled harvesting condition as a function of the applied electrophoretic force, imposed on the substrate by means of a DC voltage varied from 0 to -3kV. The AFM shows that the amount of deposited material increases up to six times when passing from an uncharged to the -3kV charged case. The model predictions are highly consistent with the AFM measurements and pointed out that the electric field in flame significantly alters the CNP deposition velocities and impact angles, which are likely to affect the properties of the film. [Display omitted] • Proposed model is able to reproduce AFM results for particle deposition. • Electrophoresis is effective in harvesting naturally charged particles in flame. • Electrophoresis is the dominant phenomenon when active for particle deposition. • Electrophoresis increases up to 6 times the collection rate of charged particles. • Electrophoresis increases impact velocity of collected particles on substrate. [ABSTRACT FROM AUTHOR]

In this paper a 3-D electrothermal (ET) analysis of a DC–DC parallel resonant converter (PRC) for constant current (CC) application is presented. A full 3-D ET simulation approach is proposed at application level to provide a support for the design stage and to analyse possible fault conditions inside the active devices. Simulations and measurements have been performed on a 100 W–2 A prototype of a PRC-CC circuit with 80 kHz nominal switching frequency. In particular, in the reported case study, the analysis has been focused on the full-bridge section of the circuit in order to prove the effect of the soft switching operation, introduced by the resonant technique, and consider the effect of possible fault conditions. To this purpose an unexpected short-circuit condition on a power MOSFET composing the H-bridge is considered, to evaluate the ET circuit behaviour and the time-to-failure of the power section. Considerations are carried out in terms of minimum requirements of protection circuits which must be fulfilled in order to avoid catastrophic system failure. A second power converter, rated for 1.5 kW, has been then designed, based on the same circuital topology, and an ET simulation has been performed in order to carry out considerations on the effect of mismatches among the input bridge devices. [ABSTRACT FROM AUTHOR]

Mediterranean mesophotic hard bottoms are mostly characterized by coralligenous banks. Although investigations on this habitat have increased in the last years, knowledge about its structure and spatial variability is still very limited as most studies are focused on the description of assemblages of peculiar and small locations such as biodiversity hotspots. This study aimed at i) describing coralligenous megafauna on the western Sardinian continental shelf between 80 and 120 m of depth, ii) assessing the distribution of the dominant taxa, and iii) estimating patterns of spatial variability at different scales. The coralligenous banks were studied along five sectors of the western Sardinian continental shelf by means of Remote Operated Vehicles (ROVs) and images were analyzed to identify the main taxa or morphological groups and their abundance. Results highlighted several common patterns among sectors, with assemblages dominated by the gorgonians Eunicella cavolini and Callogorgia verticillata. On the other hand, some taxa (e.g. Callogorgia verticillata , Paramuricea hirsuta, Antipathella subpinnata, Corallium rubrum Paramuricea clavata , Poecillastra compressa and Aplidium spp.) mainly contribute to segregate the coralligenous assemblages within the considered sectors of this study. A high small-scale variability was also observed. The presence of extensive and well diversified mesophotic animal forests stresses the importance to improve the conservation of the western Sardinian continental shelf. • The structure of coralligenous banks on the Sardinian continental shelf was described. • Patterns of spatial variability at different scales were estimated. • Sardinian coralligenous bank assemblages were dominated by erect anthozoans. • Sectors segregated among them due to the local abundance of different taxa. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a novel 3D electro-thermal simulator for high power devices operating in avalanche condition will be presented. The proposed solution is based on two coupled systems: a 3D-FEM thermal simulator and a 2D electrical solver. The simulator has been implemented in MATLAB language. It is capable of simulating a large number of macro-cells composing a wide-area power devices operating in avalanche condition. The electrical solver uses a SPICE-like algorithm with a look-up-table description for every cell. The thermal problem is solved by a finite element method (FEM) in an iterative scheme with the electrical simulator. In order to prove the effectiveness of the simulator, we will present electro-thermal simulations in Unclamped Inductive Switching (UIS) conditions for a high power Trench-IGBT. [Copyright &y& Elsevier]

In organic-enriched sedimentary systems, like many Mediterranean coastal lagoons, a detailed analysis of sediment grain size composition and partitioning within the muds is crucial to investigate sedimentological trends related to both hydrodynamic energy and basin morphology. In these systems, sediment dynamics are particularly important because the partitioning and transport of fine sediments can strongly influence the redistribution and accumulation of large amounts of organic matter, and consequently the distribution of benthic assemblages and the trophic status and functioning of a lagoon. Nevertheless, studies on benthic–sediment relationships have been based mainly on a rather coarse analysis of sediment grain size features. In muddy systems, however, this approach may impede a proper evaluation of the relationships and effects of the distribution of fine sediment and organic matter on the biotic benthic components. Here we show that the distribution of sedimentary organic matter (OM) and total organic carbon (TOC) in the Cabras lagoon (Sardinia, Italy) can be explained (i.e., predicted) as a function of a nonlinear increase in the amount of the cohesive fraction of sediments (⩽8μm grain size particles) and that this fraction strongly influences the structure, composition and distribution of macrobenthic assemblages. Even in such a homogeneously muddy system, characterized by “naturally” occurring impoverished communities, impaired benthic assemblages were found at ⩽8μm, OM, TOC contents of about 77%, 11% and 3.5%, respectively. A review of studies conducted in Mediterranean coastal lagoons highlighted a lack of direct integrated analysis of sediment features and the biotic components. We suggest that, especially in organic-enriched coastal lagoons, monitoring programs should primarily investigate and consider the cohesive fraction of sediments in order to allow a better assessment of benthic–sediment relationships and ecological quality of the system. [Copyright &y& Elsevier]

Abstract: Introduction: Neurokinin B (NKB) is a neuropeptide belonging to the family of tachykinins-related peptides that elicits contractility of human myometrial strips in vitro. The present study evaluates whether placental mRNA and peptide expression of NKB change in women at preterm labor. Methods: A group of 26 women with singleton pregnancies were enrolled in the study. Placental tissue specimens were collected from pregnant women delivering after elective cesarean section, after labor at term, or after preterm labor. Changes in placental NKB mRNA and protein expression were evaluated by real-time quantitative RT-PCR analysis and by immunofluorescence respectively. Results: Placental mRNA expression of NKB was significantly higher after term and preterm labor (P <0.001) than cesarean section, and highest after preterm labor. Immunofluorescent staining in placentas from preterm or term labor was more intense than after cesarean section (P <0.001). In particular, NKB protein expression was higher in placentas collected after preterm labor than those collected after term labor. Discussion: Neurokinin B mRNA and protein are highly expressed in placenta at term and preterm labor; thus, the involvement of this neuropeptide in the events cascade leading to parturition may be suggested. [Copyright &y& Elsevier]

We studied the spatial variability and within-year temporal changes in hydrological features, grain size composition and chemical characteristics of sediments, as well as macrofaunal assemblages, along a heavily modified inlet in the Gulf of Oristano (western Sardinia, Italy). The inlet connects the Cabras lagoon to the gulf through a series of convoluted creeks and man-made structures, including a dam and fish barriers built in the last three decades. Sediments were muddy and mainly composed of the “non-sortable” fraction (i.e., <8μm particle size) in all four areas investigated: Lagoon, Creeks, Channel and Seaward. Along the inlet, however, the ratio between the <8μm and the 8–64μm fractions was highest in Creeks and Channel, between the fish barriers and the dam, suggesting impaired hydrodynamics. Consistently, steep gradients in water salinity, temperature and dissolved oxygen concentrations were found in proximity to the fish barriers. The whole inlet was characterized by a major organic enrichment of sediments, with up to an annual mean of 33.6% of organic matter and 11.7% of total organic carbon in Seaward due to the presence of seagrass leaf litter. Acid-volatile sulphide and chromium-reduced sulphur concentrations were highest throughout the year in Seaward and Lagoon, respectively, with a peak in summer. Consistently, the whole inlet supported low structured macrofaunal assemblages dominated by few opportunist species, with a relatively lower diversity in Lagoon throughout the year and the highest abundances in Seaward in summer. We infer that the presence of artificial structures along the inlet, such as fish barriers and the dam, impair the lagoon-gulf hydrodynamics, sediment exchange and animal recruitment and colonization. We suggest that the removal of these structures would favour water renewal in the Cabras lagoon, but would also increase the outflow of organic C-bonding fine particles into the gulf with serious consequences for Posidonia oceanica and Cymodocea nodosa seagrass meadows. We conclude that all possible consequences of such initiatives should be carefully considered before any action is taken. [Copyright &y& Elsevier]

Abstract: Aims: Germline mutation of the E-cadherin gene (CDH1) accounts for the Hereditary Diffuse Gastric Cancer (HDGC) syndrome. Fourteen pedigrees with Diffuse Gastric Cancer that fulfilled the International Gastric Cancer Linkage Consortium (IGCLC) criteria were selected and screened for CDH1 germline mutations. Methods: The entire coding region of the CDH1 gene and all intron–exon boundaries were analyzed by direct sequencing in the 14 families fulfilling the IGCLC criteria. E-cadherin immunohistochemical expression was evaluated on tumour as well as normal formalin-fixed paraffin embedded tissues. Results: A novel germline missense mutation was found. It was a single C→T substitution in exon 8, resulting in a transition of CCG→CTG (C1118T; Pro373Leu) demonstrated in the proband and her brother. At immunohistochemical analysis, the staining intensity was reduced and considered weakly positive (15%). Conclusions: The first CDH1 germline mutation of an Italian family is herein reported. The present missense mutation has never been described so far. [Copyright &y& Elsevier]

Abstract: A year-round biomonitoring study on blue mussels (Mytilus galloprovincialis) was carried out in 4 selected sites along the Gulf of Oristano (Sardinia, Italy): a commercial port (Port), the outlet of the S''Ena Arrubia and Marceddì lagoons (in the catchment area of intensive agricultural and diary activities, and abandoned mining), and a reference site (North). Heavy metal concentrations in sediments from Marceddì were 2–3 to 10–20 times higher in Pb, Cd and Zn, respectively, than those found at North and S''Ena Arrubia. Higher values (P <0.05) of micronuclei frequency were detected in mussels from Marceddì and Port compared to those detected in mussels from North and S''Ena Arrubia. DNA damage in animals from North was significantly lower than that at the other sites. Results of acetylcholinesterase inhibition consistently showed the strongest effects in mussels from Port and Marceddì. Our results suggest that these biomarkers can be used in coastal marine biomonitoring as early signals of exposure and adverse effects along a pollution gradient. [Copyright &y& Elsevier]

The electric-field assisted deposition is successfully proposed as a method for the manufacturing of carbon nanostructured films with tunable properties, benefiting from the superimposition of electric fields on the thermophoretic deposition. Morphology, optical, and thermo-resistive properties of the carbon nanoparticle (CNP) films have been studied by UV–vis Absorption Spectroscopy, Scanning Electron Microscopy, Atomic Force Microscopy, and Current-Voltage analysis. In comparison to thermophoresis alone, the introduction of an electric field results in a six-fold increase in the deposition rate characterized by a non-linear film growth influenced by a three-fold augmentation in surface roughness and polarization effects. Notably, the surface morphology of the CNP films undergoes modification, exhibiting larger grains and a reduced optical band gap energy. Moreover, while maintaining a non-ohmic behaviour, the electric field plays a crucial role in increasing by about two orders of magnitude the electrical conductance of CNP films at ambient temperature. This effect is accompanied by a decrease in temperature sensitivity, attributed to the low and nearly temperature-independent activation energy for the tunneling of electrons in the percolative network. In summary, electric-field assisted deposition is a promising approach to tailor the thermal response of CNP films, which could be beneficial for the development of next-generation sensors. [Display omitted] • Electric field-assisted thermophoretic deposition of flame-made CNP films is proposed. • Film morphology and electrical conductivity can be controlled. • Thermal response of CNP films can be tailored by electric field-assisted deposition. [ABSTRACT FROM AUTHOR]

Reactive adsorption of hydrogen sulphide (H 2 S) from gaseous streams at room temperature with mixed Zn and Cu active phase supported onto γ-alumina is dealt in this manuscript. Sorbents with a fixed total metal content and variable Cu:Zn ratios were prepared by impregnation of commercial γ-alumina spheres in order to investigate the role of the support and the possible synergic effect between the two metals on the adsorption mechanism and performance. H 2 S (500–3000 ppmv in N 2 ) removal tests were run under dynamic conditions at 30 °C. Experimental techniques such as BET and pore size distribution by N 2 -adsorption, SEM-EDX, XRD and DRIFT analysis were coupled for the characterization of fresh and spent sorbents. TPD/TPO experiments on saturated sorbents were performed to assess their regenerability and allowed the speciation of adsorbed sulphur species, testifying the complexity of the surface reactions and the effect of the support. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we experimentally demonstrate that SiC high voltage Power MOSFTEs exhibit an unstable electro-thermal behavior for given electrical conditions, depending on the chip thermal impedance. This instability can lead to hot-spot formation and eventually thermal runaway whit subsequent device destruction after a stressful short-circuit. The analysis was carried out on a commercial 1.2kV SiC Power MOSFET by investigating the device electro-thermal behavior in short-circuit operation with a state-of-art IR thermographic set-up. By biasing the device at different gate voltages, the stable and unstable regions are evidenced with electrical and thermal measurements. Finally an unstable behavior is triggered and an hot-spot coherent with the failure location is demonstrated. [Copyright &y& Elsevier]

The input flow of groundwater from the seabed to the coastal ocean, known as Submarine Groundwater Discharge (SGD), has been only recently recognized as an important component of continental margin systems. It potentially impacts physical, chemical and biological marine dynamics. Independently of its specific nature (seepage, submarine springs, etc.) or fluid chemical composition, a SGD is generally characterized by low flow rates, hence making its detection and quantification very difficult, and explaining why it has been somewhat neglected by the scientific community for a long time. Along with the growing interest for SGDs emerged the need for in-situ observations in order to characterize in details how these SGDs behave. In this work, we describe the morphology of a pockmark field, detected in the Southern Tyrrhenian Sea (Mediterranean Sea), and provide observational evidences of the presence of active submarine springs over the coastal shelf area. We describe the effect of the fluid seeps on the water column stratification close to the main plumes and in the neighbouring areas, providing quantitative estimates of the intensity of the turbulent mixing and discussing their potential impact on the seabed morphology and pockmark formation in the context of turbulent buoyant plumes analytical modelling. [ABSTRACT FROM AUTHOR]

We depict the relative sea-level rise scenarios for the year 2100 from four areas of the Italian peninsula. Our estimates are based on the Rahmstorf (2007) and IPCC-AR5 reports 2013 for the RCP-8.5 scenarios ( www.ipcc.ch ) of climate change, adjusted for the rates of vertical land movements (isostasy and tectonics). These latter are inferred from the elevation of MIS 5.5 deposits and from late Holocene sea-level indicators, matched against sea-level predictions for the same periods using the glacio-hydro-isostatic model of Lambeck et al. (2011). We focus on a variety of tectonic settings: the subsiding North Adriatic coast (including the Venice lagoon), two tectonically stable Sardinia coastal plains (Oristano and Cagliari), and the slightly uplifting Taranto coastal plain, in Apulia. Maps of flooding scenarios are shown on high-resolution Digital Terrain Models mostly based on Lidar data. The expected relative sea-level rise by 2100 will change dramatically the present-day morphology, potentially flooding up to about 5500 km 2 of coastal plains at elevations close to present-day sea level. The subsequent loss of land will impact the environment and local infrastructures, suggesting land planners and decision makers to take into account these scenarios for a cognizant coastal management. Our method developed for the Italian coast can be applied worldwide in other coastal areas expected to be affected by marine ingression due to global climate change. [ABSTRACT FROM AUTHOR]

Angiogenesis is a biological process by which new capillaries are formed from pre-existing vessels. It occurs in physiological and pathological conditions, such as tumours, where a specific critical turning point is the transition from the avascular to the vascular phase. Tumour angiogenesis depends mainly on the release by neoplastic cells of growth factors specific for endothelial cells that able to stimulate the growth of the host''s blood vessels. This review summarises the literature concerning the relationship between angiogenesis and progression in human neuroblastoma, the most common extracranial solid tumour of infancy and childhood. It is becoming increasingly evident that agents which interfere with blood vessel formation also block tumour progression. Accordingly, anti-angiogenic tumour therapy has gained much interest in preclinical and clinical assessments. The recent applications of anti-angiogenic agents which interfere or block neuroblastoma progression are reviewed. [Copyright &y& Elsevier]

The reactive adsorption of H 2 S on CuO-ZnO dispersed onto activated carbon was investigated in different gas streams, containing either O 2 , H 2 O or O 2 /H 2 O, at room temperature and in a lab-scale fixed-bed reactor. Sorbents performances were analysed in terms of H 2 S capture rate and capacity, and results correlated with the sulphur species formed upon adsorption under different experimental conditions. Temperature Programmed Desorption (TPD), porosimetric and XPS analyses were performed in order to support the adsorption dynamic tests. The co-presence of O 2 and H 2 O caused a remarkable increase in H 2 S adsorption capacity, in particular for Cu-containing sorbents, favouring the formation of various sulphur species such as sulphides, sulphates and, above all, elemental sulphur. The analysis of the experimental data set showed the occurrence of two main H 2 S oxidation mechanisms with different rates: the first one quickly formed metal sulphates utilizing lattice oxygen from metal oxide clusters or superficial oxygen species; the second process was slower and required moisture and molecular oxygen in the feed gas to catalytically form elemental sulphur chains that progressively filled-up the sorbent microporosity. Image 1 • Enhanced H 2 S capacity of CuO-ZnO/AC sorbents with O 2 and H 2 O. • Reactive adsorption mechanism starts with the initial fast formation of metal sulphates. • CuO catalyzes H 2 S oxidation to elemental S in the presence of H 2 O and O 2. • Large sorption capacity related to the filling up of micropores with elemental S. [ABSTRACT FROM AUTHOR]