Search

A microkinetic analysis in terms of DFT-calculated temperature-dependent Gibbs free energies was performed for the oxidation reactions of CO and H 2 on a model Mn 4 O 8 cluster. Apparent activation energies data predict a peculiar CO preferential oxidation pattern of Mn(IV) sites in presence of hydrogen (PROX) substantiated by the unprecedented PROX behavior of a nanocomposite MnCeO x catalyst in the range of 353–423 K under both ideal and real process conditions. Micro- and macrokinetic data on the "model" cluster and "real" catalyst are discussed. [Display omitted] • Unprecedented CO-PROX behavior is showed by nanocomposite MnO x catalyst. • PROX activity is confirmed by model DFT calculations and experiments on real catalytic systems. • CO and H 2 oxidation reactions occur on different Mn sites, whose presence depends on the temperature. • DFT-based microkinetic analysis can be easily refined to take into account temperature and site number effects. • Manganese oxide could be used to heavily reduce CO level in hydrogen feeds. [ABSTRACT FROM AUTHOR]

The paper proposes a new solution, in the context of equivalent storm models, for long-term statistics of ocean storms. These models are essentially based on the concept of equivalent sea which consists of substituting the actual storms at a given location with a sequence of equivalent storms, achieved from a statistical perspective. Firstly the Equivalent Triangular Storm (ETS) was proposed in which triangular storms were considered. The model was then generalized assuming a power law for a more realistic description of the storm history in time domain. The two models were developed following the same logic and assuming the equivalent storm symmetric with respect to its peak. In both cases the solution for the calculation of return period of a sea storm whose maximum significant wave height is greater than a given threshold is achieved, but only for ETSs it has a closed form and for all the others shapes it requires a numerical calculation. The main focus of the present work is to combine in a unique model the main advantages of the two previous ones, that is to obtain an optimized shape (as for EPS) and closed from solutions for the long-term statistics (as for ETS). An exponential law is introduced, taking into account asymmetry in storm profile. The long-term statistics of ocean storms is then investigated via this new Equivalent Exponential Storm (EES) model, by analyzing the effects of asymmetry between the growth and decay phases of each storm. Data from National Data buoy Center (NDBC) are processed for the new EES model validation and comparison with previous ETS and EPS. The results show that the assumption of asymmetric storm profile does not lead to significant changes of the long-term statistics, but could be very useful in other kinds of application as it enables a more realistic representation of storm history. Finally, in comparison with ETS and EPS, it has been seen that EES provides a better representation of actual storm duration. [ABSTRACT FROM AUTHOR]

The paper deals with the directional analysis of sea storms in the Atlantic and Pacific Oceans and in the Mediterranean Sea. The main focus of the work is to investigate the variability of wave directions during sea storms. The analysis is carried out starting from significant wave height and wave direction time series. At the first stage storms are selected from time series without conditions on wave direction. Subsequently the directional analysis of each storm is performed by considering the wave direction associated to each sea state during the storm. A methodology to classify the “directional storms” pertaining to a certain directional sector is proposed. Finally a technique to determine the main directions of occurrence of the strongest sea storms and the appropriate width of sectors for directional analysis is proposed. Results are useful for different kind of applications such as directional long-term predictions for the design process of angle-dependent structures or for wave energy converter devices. [ABSTRACT FROM AUTHOR]

The Natural Ocean Engineering Laboratory (NOEL) of the Mediterranea University of Reggio Calabria, Italy, is the first ocean engineering laboratory working in the field. A peculiarity of the lab is that a local wind from NNW often generates sea states consisting of pure wind waves that represent a small scale model, in Froude similarity, of ocean storms. Significant wave height ranges between 0.20 m and 0.80 m, with peak periods between 2.0 s and 3.6 s. This local wind is very stable and sometimes stays steady from morning to evening. The tidal amplitude is very small (typically within 0.10 m). The physical structure was built after the successful experience of some initial small-scale field experiments directed by Professor Paolo Boccotti since 1989. [ABSTRACT FROM AUTHOR]

Highlights: [•] Carriers control texture, chemical and adsorption properties of Cu–ZnO system. [•] Methanol is a primary product of CO2-hydrogenation reaction at T ≤473K. [•] A consecutive-parallel reaction network lead to CO, mostly at T >473K. [•] Ceria strongly promotes CO2 adsorption and functionality of Cu–ZnO system. [•] Textural and chemical features explain the superior activity of Cu–ZnO/ZrO2 system. [Copyright &y& Elsevier]

Aquaporin-9 (AQP-9) regulates tissue hydration by promoting transmembrane exchanges of both water and solutes, such as lactate. The latter is a key metabolite of primary spermatocytes and of maturing haploid germ cells (h-GCs). The present investigation was aimed at immunolocalising human AQP-9 in both normal and varicocele testes. Histology and immmunocytochemistry were investigated in archival biopsies from 20 varicocele testes and in eight unaffected ones. AQP-9 immunostaining was performed using a rabbit antibody, and either focal or diffuse cell membrane labelling was recorded. Varicocele testes showed disarranged tubular compartments, with sloughing h-GCs, tissue hyperhydration, spermiogenesis failure and fibrosis. AQP-9 immunohistology of the control testes showed a diffuse cell membrane staining of the primary spermatocytes and h-GCs, without any positive reaction of spermatogonia and Sertoli cells. AQP-9 cell expression in the varicocele testes was focal or lacking in both adluminal and sloughing GCs. AQP-9 expression occurs in normal human testis, at cell membrane of primary spermatocytes and h-GCs, suggesting a possible role of AQP-9 in the water and lactate transport from Sertoli cells to GCs. AQP-9 is focal or lacking in adolescent varicocele testes, and this suggests AQP-9 to be downregulated in such testicular disorder, leading to lactate deprivation with subsequent hypospermatogenesis. [ABSTRACT FROM AUTHOR]

Abstract: Several polymers with ion exchanging groups showing acidic strength comparable with that of “concentrated” sulfuric acid were used to prepare silica-heterogenized perfluorosulfonic (PFS) acid catalysts by either incipient wetness impregnation of commercial silicas or sol–gel and precipitation routes. Solid-acid catalysts were probed in the synthesis of acetal at 4°C and 3atm in a stirred batch reactor. A systematic analysis of activity data and the acid strength of the various catalysts points out a direct relationship between the acidic capacity and catalytic activity, pointing out a minor influence of the strength distribution on the main reaction path. [Copyright &y& Elsevier]

Abstract: The heterogeneous catalytic etherification of glycerol with tert-butyl alcohol was investigated in presence of lab-made silica supported acid catalysts. As reference, two commercial acid ion-exchange resins were also used. Experiments were carried out in batch mode at T R ranging from 303 to 363K. An increase in reaction temperature favors the formation of di-substituted ethers. The etherification reaction proceeds according to a consecutive path and the surface reaction between adsorbed glycerol and protonated tert-butanol (tertiary carbocation) can be considered as the rate determining step. Steric hindrance phenomena and water hinder the formation of tri-substituted ether (TBGE). As expected, water removal was necessary to allow the higher ethers formation. The specific activity (turnover frequency, TOF) of A-15 catalyst is significantly higher than that of the other studied acid systems, due to the wide pore diameter that allows an easier accessibility of the reagent molecules. [Copyright &y& Elsevier]

Abstract: A series of Cu–ZnO/ZrO2 catalysts (Znat/Cuat, 0–3; ZrO2, 42–44wt.%) with markedly improved total (SA, 120–180m2/g) and metal surface area (MSA, 9–63m2/g) has been synthesized via the reverse co-precipitation under ultrasound field. Structure, adsorption properties and surface reactivity were probed by BET, XRD, TPR, N2O-titration and TPD measurements of H2, CO and CO2, while the activity pattern in the CO2 to CH3OH hydrogenation reaction (T R, 433–473K; P R, 1.0MPa) has been addressed. An optimum ZnO loading (Znat/Cuat, 0.3–0.8) ensures higher process productivity, while the apparent structure sensitive character of the title reaction relies on the synergism of metal hydrogenation and oxide basic sites (dual-site). The extent of the oxide/metal interface, probed by Cuδ+/Cu0 and oxide-to-metal surface area (OSA/MSA) ratios, is the key-parameter allowing the normalization of the catalytic specific activity in a wide range (3–60%) of metal dispersion and the consequent structure insensitive character of the CO2 hydrogenation reaction. [Copyright &y& Elsevier]

Abstract: A comparative testing of flat and hollow fiber Nafion/PEEK-WC catalytic membranes in the partial oxidation of propane to oxygenates (n-propanol, isopropanol, propionic aldehyde and acetone) with Fe2+–H2O2 Fenton system in a multifunctional three-phase reactor (3PCMR) under mild conditions (T R, 70–120°C; P R, 140kPa) has been accomplished. The features of the multifunctional 3PCMR that enables reaction along with product separation and recovery are discussed. The influence of the membrane geometry on selectivity and distribution of reaction products in gas and liquid phases is outlined. Hollow fiber systems ensure higher productivity per unit of reactor volume, higher selectivity to primary oxidation products (n-propanol and isopropanol) and a more effective product recovery. [Copyright &y& Elsevier]

Abstract: The structure and redox properties of low-loaded (0.015–0.73wt% Fe) FeO x /SiO2 catalysts obtained by adsorption–precipitation of Fe2+ were probed by Mössbasuer and TPR techniques. Oxide dispersion data, obtained by deconvolution of Mössbasuer and TPR spectra, signal the speciation of the active phase into “isolated”FeO x sites, “2-d FeO x patches” and “3-d Fe 2 O 3 clusters”. The reactivity of FeO x /SiO2 catalysts in the selective oxidation of CH4 and C3H8 in the range 475–650°C has been assessed. Basic relationships amongst dispersion, specific rate of alkane conversion and product formation signal that the selective oxidation functionality depends upon local environment and oxygen bond strength of active sites, their distribution being closely related to the efficiency of synthesis route. [Copyright &y& Elsevier]

Abstract: The effects of the preparation method (deposition–precipitation, incipient-wetness, combustion) on the structure and redox properties of 1% Au/CeO2 catalyst have been probed by TPR, XRD, and TEM techniques. The catalytic pattern in total (COX) and selective (SCOX) CO oxidation has been assessed by temperature programmed reaction tests in the range 273–473K. Controlling residual chlorine, the synthesis route determines the strength of the Au–CeO2 interaction which affects both the reduction of the active phase and the CO oxidation functionality. Removal of chlorine by washing in a diluted alkaline solution enables then an easy reduction of Au precursor levelling off the reactivity of the Au/CeO2 catalysts. [Copyright &y& Elsevier]

Background: The symptoms affecting the sexual sphere in women's during climacteric are of high prevalence. Objective: To describe the fundamental aspects of human sexual response during the climacteric and to analyze the effect of climacteric replacement hormone therapy. Methodology: A revision of existing bibliography was done, from MEDLINE and LILACS databases, finding a total of 465 articles. From that group, those which presented the highest scientific rigor were selected. Results: It was found that climacteric affects in a variable way the female sexual response, affecting not only her biological sphere, but her psychological and behavioral spheres. It can be seen that there are endocrine and trophic factors acting upon the different tissues which modify the coital factor of this response. It was also found that sexual desire and orgasm are affected in a more variable way, the affection not exclusively depending on biological parameters. Conclusion: The use of hormone replacement lowers the deterioration of the human sexual response during climacterium. [ABSTRACT FROM AUTHOR]

Abstract: The effects of the preparation method (combustion and incipient wetness) and Co loading (1–5 wt%) on the structure, redox, and morphological properties of the Co/CeO2 system were probed by X-ray diffraction, X-ray photoemission spectroscopy, scanning electron microscopy, CO and H2 chemisorption and temperature-programmed desorption measurements. Synthesis route and Co-loading control the structure and morphological properties, markedly affecting the reactivity of the Co/CeO2 system in the Fischer–Tropsch synthesis (FTS) reaction (; ). Both metal–support interaction(s) and Co dispersion control the strength and relative concentration of CO and H2 adsorption sites enabling marked differences in the specific site–time–yield of the various catalysts. [Copyright &y& Elsevier]

The effects of preparation method on surface structures and catalytic properties in the selective oxidation of CH4 to HCHO with O2 (MPO) of low-loaded (0.09–0.43 wt.% Fe) FeOx/SiO2 catalysts have been addressed. The DR-UV-Vis patterns prove that the preparation route, based on “adsorption–precipitation” of FeII precursors on silica under anaerobic conditions (ADS/PRC), enhances the dispersion of the active phase in comparison to the conventional “incipient-wetness” route. FTIR of adsorbed NO data signal the presence on silica of several “isolated” Fe moieties with a different surface coordination. A higher FeOx dispersion confers a superior performance to ADS/PRC FeOx/SiO2 catalysts in terms of specific rate of CH4 conversion (σCH4) and HCHO formation (#x03B5;HCHO) of Fe atoms which result in quite larger HCHO productivity values (STYHCHO). [Copyright &y& Elsevier]

The partial oxidation of methane to formaldehyde (MPO) with molecular O2 has been investigated on various bare and Fe-doped commercial silica catalysts at 650 °C. The influence of the Fe loading (0.01–3.2 wt.%) on the catalytic pattern and steady-state properties of the catalysts have been evaluated. The dispersion and coordination symmetry of surface Fe3+ species have been investigated by EPR analysis. “Isolated Fe3+ ions”, “small Fe2O3 clusters” and “Fe2O3 particles” are present on the surface of the FeOx/SiO2 catalysts, their relative concentration depending upon the loading. Iron species, irrespective of the state of aggregation, enable the reactivity of the silica surface, whilst the highest HCHO productivity is associated with an optimum surface Fe loading (0.05–0.1 Feat nm−2). The different reactivity of the various Fe-doped silica catalysts has been rationalised and normalised in terms of different concentration of “isolated Fe3+ species” and “aggregated Fe2O3 moieities”. [Copyright &y& Elsevier]

Prostatic malacoplakia associated with prostatic abscess is an extremely rare disease. We present a case of prostatic malacoplakia presenting as a prostatic and seminal vesicle abscess in a patient with diabetes. The diagnosis and management are discussed, and the literature is reviewed.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Hydrogen permeation through uniaxially strained thin SiO x based gas barrier films, formed at room temperature and ambient pressure on PET foil substrates by UV photochemical conversion (Photoconversion), was investigated using a dedicated measurement system. Hydrogen permeation measurements were conducted as a function of the stack of laminated single SiO x barrier films, of the sample temperature as well as of the uniaxial mechanical strain applied to the samples. The results demonstrate a significant overall improvement of the hydrogen barrier properties for both single SiO x barrier films on PET and laminated single SiO x barrier films on PET. In the case of strained samples, the hydrogen barrier properties deteriorate due to stress-induced crack formation in the barrier films. This deterioration is strongest for strained single SiO x barrier films but can be substantially reduced by laminating single SiO x barrier films. • Hydrogen permeation measurements as a function of sample strain and temperature • Use of a dedicated hydrogen permeation measurement system for strained samples • Hydrogen permeation through thin SiO x gas barrier films on PET foil substrates • SiO x barrier films formed by UV photochemical conversion of perhydropolysilazane • Hydrogen barrier improvement for single and laminated SiO x barrier films on PET [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effectiveness of incisions of Peyronie's plaque and vein grafting combined with contralateral plication to straightening the penis. Patients and methods: Twenty-four patients with Peyronie's disease were treated surgically with a vein patch grafting technique to correct penile curvature. Median penile deviation was 70° (range 60-90°), in 1 patient curvature was 30° and all were unable to have normal sexual intercourse. The deep dorsal vein was excised and opened longitudinally. Transverse relaxing incisions about 1-2 cm long were made on the plaques at the point of maximal curvature, then, two other lateral incisions were made on both ends at 3 and 9 o'clock. The endothelial side of the harvested vein was placed in contact with the cavernous tissue to cover the defect created. Application of the contralateral surface of the tunica albuginea was performed in 21 cases to straighten the penis. Results: After a median follow-up of 24 months, 19 patients were able to perform sexual intercourse, 3 patients who required intracavernous injection to maintain erection presented pre-operative adverse factors affecting erectile function. One patient returned to baseline pre-operative curvature. Twelve patients reported penile shortening, although only 5 patients were concerned about it. None of the patients permanently lost sensation in the glans of the penis. Palpable knots on the site of plication were reported in 5 patients. Conclusions: Plaque incision and placement of a deep dorsal vein patch graft, combined with contralateral corporeal plication, is a relatively simple, safe and effective alternative to correct angulations greater than 60°. [ABSTRACT FROM AUTHOR]

Objective To define the neonatal management and ultimate surgical correction via the anterior sagittal transanorectal approach (ASTRA) in cases of neonatal urinary hydrometrocolpos associated with a persistent urogenital sinus (UGS). Patients and methods We report three patients with UGS (with no ambiguous genitalia) and urinary hydrometrocolpos in whom prenatal ultrasonography showed cystic dilatation of the pelvis. Two patients were temporarily treated with intermittent vaginal catheterization and antibiotic prophylaxis, and in one a cystostomy was necessary to temporarily drain the urine. At the age of 6–8 months the patients underwent reconstructive surgery of the UGS via the ASTRA, under a previous protective colostomy. Results The mean (range) age of the patients at the last follow‐up was 18.7 (8–32) months. A good cosmetic result was obtained in all patients. The vagina was dilated briefly with no anaesthesia in each patient. Patients had normal faecal control after the colostomy was closed and none had urinary incontinence. Conclusions When possible, intermittent vaginal catheterization permits sufficient temporary drainage of the urinary hydrometrocolpos associated with a persistent UGS. Subsequent ASTRA allows good exposure of the UGS, assuring the preservation of the anorectal innervation and of the sphincteric mechanism. [ABSTRACT FROM AUTHOR]

For seismic assessment of wind turbines in seismically-active areas, International Standards and Guidelines allow the combination of two uncoupled analyses under environmental and earthquake loads, respectively. The separate earthquake response is generally computed including an additional aerodynamic damping in the structural model. Although some work has been done to estimate the effectiveness of uncoupled analyses for land-based wind turbines, and determine appropriate levels of aerodynamic damping, to date no similar studies have been carried out for offshore wind turbines. This paper assesses the accuracy of different time-domain implementations of uncoupled analyses for offshore wind turbines, and investigates pertinent levels of aerodynamic damping. The case study is a 5-MW wind turbine, resting on a tripod in intermediate waters. [ABSTRACT FROM AUTHOR]

This paper studies the dynamics and power extraction of a U-Oscillating Water Column (U-OWC) device. A three-dimensional hydrodynamic model, based on the boundary integral equations method, is implemented. The U-OWC width and wave direction are analysed and compared with a two-dimensional model based on the eigen-function expansion method. Results show that as the device width increases, the power extraction per unit width tends to the two-dimensional value. For small converter widths, which are expected to be implemented in practical applications, three-dimensional effects are relevant and provide a systematic improvement in power output per unit width, due to their influence in the device hydrodynamic characteristics. [ABSTRACT FROM AUTHOR]

The space‐time evolution of wave groups in crossing seas is investigated. Profiles were calculated by applying Quasi‐determinism theory of Boccotti in its first formulation starting first from the laboratory data and then using the theoretical spectrum used for wave generation, given that a very high crest takes place at a fixed point in the basin. The analysis of the predictions shows that the group with the high crest is given by the superposition of two wave groups, associated one to the low‐frequency component of the spectrum and the other to the high‐frequency one. Different locations of high crest occurrence were considered in order to study the effect of the change in spectrum on the deterministic profiles. The comparison between the predictions obtained by the two modalities of application of the theory shows agreement when the spectrum at any point maintains almost the same characteristic of the spectrum measured in correspondence of the high crest occurrence location. Finally the analysis of the second‐order contribution revealed that the nonlinear effect gives higher and steeper crests and lower and flatter troughs than the linear ones whatever is the sea state considered being the greatest in presence of the wind wave dominated spectrum. [ABSTRACT FROM AUTHOR]

Abstract: This work was aimed at investigating the catalytic behaviour of MnCeO x and MnZrO x systems in biodiesel production by sunflower oil transesterification reaction with methanol. Surface and textural properties were deeply investigated by different techniques whereas CH3OH surface reactivity was evaluated by FT-IR and MeOH-TPSR measurements, in order to disclose the nature of the active sites and to provide evidences of a complex reaction mechanism, in which a synergic role of Mn and carrier significantly affects the methyl esters productivity. Direct relationship among catalytic activity, density of strong basic sites and amount of adsorbed bidentate methoxy species were found. The doubly-bridging coordinated methoxy species were recognized as the ones mainly involved in the transesterification reaction. Anyway, even if the basic strength resulted to be considered the key factor for MeOH activation, only the proper balance between basic and acid sites controls catalyst behaviour. The linear dependence of activity with catalyst porosity clearly demonstrated that a wide porous structure is required to enhance the sites accessibility to large triglycerides (TGs) molecules. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a 3-year-long (November 2004–November 2007) study based on the use of acoustic Doppler current profilers (ADCPs) to estimate the solid transport through the three inlets of Venice lagoon. In each of the three inlets instruments were mounted both on survey boats and deployed on the channel bed. The three bottom-mounted ADCPs were positioned in the central part of the inlets, continuously monitoring vertical profiles in the water column. Periodic transects along the investigated sections were collected by the boat-mounted ADCP. Both installations measured current speed and acoustic backscatter intensity. The latter expresses the attenuation of acoustic energy due to material in the water column. The conversion of acoustic backscatter into suspended solids concentration (SSC) was carried out by means of direct measurements of concentration; also an indirect method was used. Boat-mounted ADCP acquisitions were used to calibrate and to validate the bottom-mounted ADCP data. Hourly time series of water discharge and SSC were obtained by calculation from the current speed and acoustic backscatter data recorded by the fixed ADCPs. Hourly solid flux time series were computed. The solid flux and SSC time series at the three inlets were analyzed in relation to the hydrodynamic and atmospheric conditions, highlighting the impact of intense meteorological events on the resuspension process. The lagoon sediment budget is estimated to be about 0.5×106 t/yr and shows a tendency for sediment loss. [Copyright &y& Elsevier]

Abstract: Doped Ni-based Thin Layer Catalysts (Ni-TLCs) for Catalytic Decomposition of Natural Gas (CDNG) were investigated using a new Multilayer Catalytic Reactor (MCR). The influence of K, La, Mg and Cl on activity–stability patterns of a Ni-TLC catalyst was evaluated. An inverse straight-line relationship between carbon capacity (C/Ni, number of CH4 molecules decomposed for Ni atom until complete deactivation) and reaction temperature was found independently of the dopant used. However, dopants significantly affect Ni specific activity (TOF, s−1), acting as either an electronic promoter or inhibiting Ni sintering phenomena. Reaction temperature is a key parameter in determining the evolution of coke. At low reaction temperature (<823K), carbon whiskers form prevalently on “bare” and Mg, La, and Cl doped samples, whereas only the encapsulating carbon type formed on a K doped system. High hydrogen productivity was obtained on an Mg doped catalyst which, furthermore, proved to be the most stable system. [Copyright &y& Elsevier]

Abstract: Using a new structured multilayer reactor (MLR) that houses Ni based thin layer catalysts, catalytic decomposition of natural gas (CDNG) for making “CO x -free” hydrogen in a T R range of 773–873K was investigated. The influence of Ni loading (5–50wt%), Ni particle size, T R, and GHSV (h−1) on the reaction pattern was evaluated. A volcano shape relationship between H2 space time yield and Ni loading with a maximum range of 20–25wt% was found. H2 productivity and catalyst lifetime are controlled by the nature of the coke formed on Ni active species. As such, T R and GHSV significantly affect both the kinetics and the mechanism of coking. At T R <873K and low GHSV (<2000h−1), the prevailing formation of filamentous carbon (whisker-like) prolongs the catalyst lifetime, while at T R =873K and high GHSV (>2000h−1) encapsulating carbon is formed, causing a sudden decline in catalytic activity. A preliminary attempt to find optimal operating conditions ensuring the highest values of H2 productivity is presented. The features of the MLR that allowed CDNG reaction under a quasi-isothermal regime without any pressure drop, irrespective of operating conditions and the extent of carbon formation, are discussed. [Copyright &y& Elsevier]

The influence of the Mg addition on the catalytic performance of a 20% Ni based SiO2/silica cloth system in the decomposition of methane for making “CO x -free” H2 in the TR range 773–873 K has been evaluated. As the Mgat/Niat ratio increases from 0.10 to 2.20 the incipient Ni–Mg-O interaction becomes stronger until the formation of Ni x Mg(1− x)O solid solution. The presence of Mg2+ ions allows a higher carbon capacity (C/Ni, number of CH4 molecules converted per Ni atom until complete catalyst deactivation) and consequently a higher H2 productivity of the Ni based systems which results in a smoothing effect of the unavoidable declining activity trend even if it does not affect the tip growth coking mechanism. [ABSTRACT FROM AUTHOR]

The partial oxidation of propane to oxygenates (isopropanol, n-propanol, propionic aldehyde and acetone) is attained in a multifunctional three phase catalytic membrane reactor (3PCMR) operating under mild conditions (TR, 80–120 °C; PR, 140 kPa). A comparative testing of different Nafion-based catalytic membranes mediated by Fe2+/H2O2 Fenton system has been carried out. The influences of textural and compositional properties and acid functionality on the catalytic performance of the Nafion membranes are outlined. The enhancing effect of the partial heterogenisation of the Fenton system on reaction rate and H2O2 yield is discussed. [Copyright &y& Elsevier]

Synthesis of liquid oxygenates from light alkanes (C1--C3) is achieved in a multifunctional three-phase catalytic membrane reactor (3PCMR) operating under mild conditions (TR, 80-120 °C; PR, 140 kPa). The features of superacid catalytic membranes mediated by the Men+/H2O2 Fenton system in activating C1-C3 alkanes are presented. The effect of operating conditions ([H2O2], [Men+]) on the catalyst activity is outlined. A general reaction pathway accounting for the activation of the CH bond of the alkane molecule on the superacid sites and the subsequent reaction of the activated alkane with primary reactive intermediates, generated from the Men+/H2O2 system, is proposed. The suitability of the 3PCMR in enabling simultaneous reaction and product separation is discussed. [ABSTRACT FROM AUTHOR]

The structure and morphology of carbon species generated under dry reforming of methane (DRM) at 650 and 800°C on ‘bare’ and ‘K-doped’ Ni/MgO catalysts have been comparatively investigated by Transmission Electron Microscopy (TEM) analyses of ‘used’ samples. K-addition (Kat/Niat, 0.125) strongly improves the resistance of the Ni/MgO catalyst to coking and sintering phenomena at any temperature. At 650°C, an extensive formation of filamentous (whisker carbon) carbon species on bare Ni/MgO catalyst causes the detachment of a large number of Ni particles from the support with a consequent destruction of the structure and remarkable sintering phenomena of the active phase. Considerably lower amounts of carbon deposits with a shell-like (encapsulating carbon) morphology, forming at 800°C on both catalysts, point to the Bouduard reaction as the main route of carbon deposition on Ni-based catalysts during DRM. The electronic effect induced by potassium on the active phase of the Ni/MgO system, timely monitored by a rise in Eapp of DRM from 50 to 70 kJ/mol, markedly hinders the rate of coking also affecting the morphology of carbon whiskers, by inhibiting the processes of C diffusion and nucleation across Ni particles under steady-state conditions. [Copyright &y& Elsevier]

Background: In the phase III MPACT trial, nab-paclitaxel plus gemcitabine (nab-P + Gem) demonstrated superior efficacy versus Gem alone for patients with metastatic pancreatic cancer. We sought to examine the feasibility of positron emission tomography (PET) and to compare metabolic response rates and associated correlations with efficacy in the MPACT trial. Patients and methods: Patients with previously untreated metastatic adenocarcinoma of the pancreas were randomized 1:1 to receive nab-P + Gem or Gem alone. Treatment continued until disease progression by RECIST or unacceptable toxicity. Results: PET scans were carried out on the first 257 patients enrolled at PET-equipped centers (PET cohort). Most patients (252 of 257) had ≤2 PET-avid lesions, and median maximum standardized uptake values at baseline were 4.6 and 4.5 in the nab-P + Gem and Gem-alone arms, respectively. In a pooled treatment arm analysis, a metabolic response by PET (best response at any time during study) was associated with longer overall survival (OS) (median 11.3 versus 6.9 months; HR, 0.56; P < 0.001). Efficacy results within each treatment arm appeared better for patients with a metabolic response. The metabolic response rate (best response and week 8 response) was higher for nab-P + Gem (best response: 72% versus 53%, P = 0.002; week 8: 67% versus 51%; P = 0.014). Efficacy in the PET cohort was greater for nab-P + Gem versus Gem alone, including for OS (median 10.5 versus 8.4 months; hazard ratio [HR], 0.71; P = 0.009) and ORR by RECIST (31% versus 11%; P < 0.001). Conclusion: Pancreatic lesions were PET avid at baseline, and the rate of metabolic response was significantly higher for nab-P + Gem versus Gem alone at week 8 and for best response during study. Having a metabolic response was associated with longer survival, and more patients experienced a metabolic response than a RECIST-defined response. [ABSTRACT FROM AUTHOR]

Background: A phase I/II study and subsequent phase III study (MPACT) reported significant correlations between CA19-9 decreases and prolonged overall survival (OS) with nab-paclitaxel plus gemcitabine (nab-P + Gem) treatment for metastatic pancreatic cancer (MPC). CA19-9 changes at week 8 and potential associations with efficacy were investigated as part of an exploratory analysis in the MPACT trial. Patients and methods: Untreated patients with MPC (N = 861) received nab-P + Gem or Gem alone. CA19-9 was evaluated at baseline and every 8 weeks. Results: Patients with baseline and week-8 CA19-9 measurements were analyzed (nab-P + Gem: 252; Gem: 202). In an analysis pooling the treatments, patients with any CA19-9 decline (80%) versus those without (20%) had improved OS (median 11.1 versus 8.0 months; P = 0.005). In the nab-P + Gem arm, patients with (n = 206) versus without (n = 46) any CA19-9 decrease at week 8 had a confirmed overall response rate (ORR) of 40% versus 13%, and a median OS of 13.2 versus 8.3 months (P = 0.001), respectively. In the Gem-alone arm, patients with (n = 159) versus without (n = 43) CA19-9 decrease at week 8 had a confirmed ORR of 15% versus 5%, and a median OS of 9.4 versus 7.1 months (P = 0.404), respectively. In the nab-P + Gem and Gem-alone arms, by week 8, 16% (40/252) and 6% (13/202) of patients, respectively, had an unconfirmed radiologic response (median OS 13.7 and 14.7 months, respectively), and 79% and 84% of patients, respectively, had stable disease (SD) (median OS 11.1 and 9 months, respectively). Patients with SD and any CA19-9 decrease (158/199 and 133/170) had a median OS of 13.2 and 9.4 months, respectively. Conclusion: This analysis demonstrated that, in patients with MPC, any CA19-9 decrease at week 8 can be an early marker for chemotherapy efficacy, including in those patients with SD. CA19-9 decrease identified more patients with survival benefit than radiologic response by week 8. [ABSTRACT FROM AUTHOR]

This paper presents the main results obtained during the European project (FCH-JU) “LoLiPEM – Long-life PEM-FCH & CHP systems”. The paper describes significant improvements in the polymer electrolyte by tailored heat treatments for cross-linking of Sulfonated Poly(ether ether ketone) (SPEEK), obtained without any addition of cross-linker species. The reported properties of the ionomers include mechanical properties, gas permeability and ionic conductivity. Innovative gas-diffusion electrodes are fabricated by the electrochemical deposition of Pt catalyst; the fuel cell current–voltage characteristics are reported with Nafion and SPEEK-based binder. The fuel cell performances at 80 °C of membrane-electrode-assemblies containing a SPEEK membrane with a cross-linking degree of 32% are among the best in the literature compared with the PEMFC using membrane alternative than Nafion. [ABSTRACT FROM AUTHOR]

Highlights: [•] Differently prepared Cu-Zn-Zr catalysts were used in CO2 hydrogenation reaction. [•] Catalyst composition and preparation method affect the physico-chemical properties. [•] The gel-oxalate coprecipitated catalyst showed high CH3OH productivity and stability. [•] The interaction of sites at metal-oxide interface plays a key catalytic role. [Copyright &y& Elsevier]

The aim of this study is to describe the synthesis of, relaxometric characterization of, pharmacokinetic properties of, and animal imaging experiments with a new, low molecular weight gadolinium complex with high binding affinity toward serum albumin. The gadolinium(III) chelate (B25716/1) is based on the structure of the heptadentate ligand 1,4-bis(hydroxycarbonylmethyl)-6-[bis(hydroxycarbonylmethyl)]amino-6 methylperhydro-1,4-diazepine (AAZTA) covalently conjugated to an analogue of deoxycholic acid. The study was conducted as a comparison with that of an analogous complex based on the octadentate diethylenetriaminepentaacetic acid ligand B22956/1 (whose albumin binding properties were previously assessed). The structural modification with respect to B22956/1 leads to a system that can host two coordinated water molecules in fast exchange with bulk water with potential higher efficiency as an MRI contrast agent. On interaction with human serum albumin the expected-field-independent-relaxation enhancement is not observed, possibly as a consequence of the displacement of one of the two inner-sphere water molecules of the gadolinium complex. At clinically relevant magnetic fields, however, the plasma relaxivity of B25716/1 is markedly higher than that shown by B22956/1, owing to concomitant synergistic contributions from the electronic correlation time and water molecules in the second coordination sphere. The capability of B25716/1 to enhance tumor regions in magnetic resonance images was assessed in vivo at 3 T on a xenograft tumor mouse model prepared with PC-3 cells. B25716/1 displays signal enhancements approximately double those observed for B22956/1, in agreement with the findings of the in vitro relaxivity investigations. [ABSTRACT FROM AUTHOR]

Highlights: [•] An integrated one-step process for CO2 hydrogenation to DME is proposed. [•] Cu–ZnO–ZrO2 and HZSM-5 were combined in different reactor bed configurations. [•] A balanced ratio between metal and acid sites is crucial for high DME production. [•] Bifunctional catalysts prepared by physical mixing show superior catalytic activity. [Copyright &y& Elsevier]

Highlights: [•] Cu–ZnO–ZrO2 methanol catalyst and H-ZSM5 zeolite were used to prepare a hybrid system. [•] Different reactor bed configurations were adopted in CO2 hydrogenation to DME. [•] The physical mixing of pre-pelletized samples exhibits a superior performance. [•] The interaction of sites at metal/oxide-acid interface plays a key catalytic role. [Copyright &y& Elsevier]

Abstract: Ni and Co supported on SiO2 and Al2O3 Silica Cloth Thin Layer Catalysts (TLC) were investigated in the Catalytic Decomposition of Natural Gas (CDNG) reaction using a Multilayer Catalytic Reactor (MCR). The influence of support and reaction temperature was evaluated with the aim to design a novel catalyst suitable to develop a dual-step process to produce pure hydrogen for fuel cell. Ni and Co silica supported catalyst, due to the low metal supported interaction (MSI) characterizing such systems, were not found suitable to efficiently perform CDNG reaction. On the contrary in case alumina was used as support both metals strongly interact with surface becoming so more resistant to sintering. In addition in case the metals (both Ni and Co) strongly interact with support surface, the formation of encapsulating carbon is depressed and only filamentous carbon forms. Using Ni and Co TLC supported on Al2O3 samples it has been possible to realize a cyclic dual-step process based on reaction and regeneration in oxygen stream without any catalyst detriment. A deactivation modelling to discriminate the role of sintering and coking on the deactivation pattern is proposed. [Copyright &y& Elsevier]

Abstract: This paper reports the results obtained using a novel MnCeO x system in the transesterification reaction of refined sunflower oil with methanol. The performance of such catalysts has been compared with that of common acid supported catalysts. Results obtained revealed that MnCeO x system possesses a superior activity especially by operating at low temperatures (≤120°C). Independently of Mn loading, the redox-precipitation method for the preparation of Mn-based systems allowed to obtain always high dispersed catalysts and, as a consequence, a linear relationship between reaction rate and Mn loading was obtained. NH3-TPD and CO2-TPD measurements indicate that MnCeO x systems are characterized by a prevalent nature of basic sites. However, the catalyst performance is the result of a synergic role played by both the surface acid/base character and textural porosity. [Copyright &y& Elsevier]

Abstract: The hydrogen production through the decomposition of methane into hydrogen and carbon on Ni supported catalysts followed by catalyst regeneration in oxidative atmosphere was evaluated. Typical temperature programmed catalytic reaction (TPCR) results revealed that the nature of the carrier slightly affects the onset temperature of CH4 decomposition, while catalytic performance and regeneration capacity in O2 or CO2 streams depend on dispersion and morphology of the active phase. The “structure-sensitive” character of methane decomposition reaction has been confirmed. TEM analyses of the “spent” catalysts revealed that both “filamentous” and “encapsulating” carbon species were formed under isothermal conditions at 823K, the last being responsible for catalyst deactivation. [Copyright &y& Elsevier]

Abstract: Objectives: To investigate the immunoexpression of aquaporin-1 (AQP-1), a major transmembrane water channel, in high-grade varicocele testes, which are known to imply an unbalanced transmembrane water flow, in both tubular and extratubular compartments. Methods: Light microscopy and AQP-1 immunohistologic examination were carried out on incisional testicular biopsies from 20 adolescent boys, aged 13 to 18 years, with grade 2 or 3 idiopathic varicocele. Testicular tissue from 4 autopsied subjects of matched age were also investigated as parallel controls. Results: At microscopic examination, the tubular lumina and extracellular matrix were expanded and venular profiles dilated. Cytoplasmic vacuoles were frequent in the Sertoli cells, spermatogonia, and spermatocytes, together with premature sloughing of germ cells and residual cytoplasmic droplets inside the spermatozoa, if present. Diffuse AQP-1 positivity occurred at venular endothelial cell membranes and, unexpectedly, at the cell membranes of the Sertoli cells, diploid germ cells, and haploid cells. In the control testes, focal AQP-1 immunolabeling was confined to the microvessel endothelial cells, without any positive reaction in the tubular or extratubular compartments. Conclusions: This is the first report showing AQP-1 cell expression in adolescent varicocele testes in both tubular and extratubular compartments. It was associated with the main histologic features of unbalanced water flow in the tubular and interstitial compartments of the testis. Immunocytochemical patterns revealed AQP-1 as a possible critical reabsorption factor, acting to reduce abnormal fluid retention in endotubular cells and the extracellular matrix and, to a lesser extent, in Leydig cells. [Copyright &y& Elsevier]

This paper aims to maximize the performance of a U-type Oscillating Water Column power plant integrated into a breakwater to be built in Roccella Jonica, Mediterranean Sea, Italy. In this location, both prevalent mild waves and less frequent highly energetic sea states occur. The main challenge is to select a Power Take-Off (PTO) system able to operate with high-efficiency in this wave climate without the need of turning the power plant off for safety reasons. A non-linear time-domain wave-to wire model was developed to evaluate the performance of the Roccella Jonica power plant. Capture width ratio results for single and multi-stage Wells turbines were compared with the biradial turbine. The possibility to install a single turbine on combined air chambers was also considered to reduce the overall PTO costs. The rotational speed of the biradial turbine was found to only rarely exceed the maximum allowed limit during the most energetic sea states, while the Wells turbines too often exceeded that limit. The introduction of relief valves was found to be necessary to keep the PTO rotational speed within safety limits. Optimal turbine diameter, generator rated power and multi-chamber configuration were selected by maximizing the performance of the power plant. • Time-domain wave-to-wire model of the Roccella Jonica U-OWC power plant was developed. • Results for single and multi-stage Wells turbines were compared with biradial turbine. • Multi-chamber configurations were considered to reduce PTO costs. • Relief valves were considered to keep turbine rotational speed within safety limits. • The biradial turbine was found to be more efficient than the Wells turbines. [ABSTRACT FROM AUTHOR]

Background: GPNMB is an internalizable transmembrane glycoprotein overexpressed in multiple tumor types, including breast cancer (BC). GPNMB promotes BC metastases in a murine model and is a poor prognostic marker in patients (pts) (Rose 2010). CDX-011 (glembatumumab vedotin) is a fully human GPNMB-specific monoclonal antibody conjugated to the potent cellular toxin MMAE via a protease-sensitive peptide linker, designed to cleave upon cellular internalization. In Phase I/II studies of CDX-011 in BC (n = 42), an objective response rate (ORR) (including confirmed and unconfirmed response) of 12% overall and 20% for "triple-negative" (ER/PR/HER2-; TN) pts was observed (Saleh, ASCO 2010). Methods: The Phase II EMERGE study examined the efficacy of CDX-011 by level of GPNMB expression. Refractory BC (2-7 prior cytotoxic regimens in metastatic setting), GPNMB expression in ≥ 5% of tumor or stroma cells (as centrally determined on archival tumor), and no persistent treatment-related toxicity (including neuropathy) of ≥ Grade 2 severity were required for enrollment. Pts were stratified by GPNMB expression pattern (any tumor, low stromal or high stromal) and randomized 2:1 to CDX-011 (1.88 mg/kg IV q 21 days) or "investigator's choice" (IC) single-agent chemotherapy, and treated until progression (PD) or intolerance with IC pt crossover permitted to CDX-011 at PD. Endpoints: ORR (primary), progression-free survival (PFS), safety, pharmacokinetics, pharmacodynamics. Results: 99% of screened tumor samples expressed GPNMB. 122 treated pts (81 CDX-011 vs. 41 IC) had median age = 56 vs. 56 years; median # prior anticancer regimens = 6 vs. 5; visceral disease (liver/lung) = 83% vs. 80%; TN = 33% vs 27%, respectively. To date, 15 IC pts have crossed over to CDX-011, and 14 pts (8 CDX-011, 6 IC) continue on treatment. CDX-011 was well tolerated with less hematologic toxicity than IC; CDX-011-related toxicity included rash (overall = 38%; Grade 1 = 20%; Grade 2 = 15%; Grade 3 = 3%) and neuropathy (overall = 18%; Grade 1 = 8%; Grade 2 = 7%; Grade 3 = 2%). Conclusions: CDX-011 was a well-tolerated and active agent in this heavily pre-treated BC pt population. Preliminary analysis of the EMERGE study demonstrates enhanced activity of CDX-011 in TN as well as high GPNMB expressing BC tumors, confirming that CDX-011 is a targeted agent. This noted promising activity in advanced TN and hGPNMB enriched pt populations warrants further evaluation. [ABSTRACT FROM AUTHOR]