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Metal binder jetting (MBJ) is an additive manufacturing (AM) technology split into two process steps: printing and sintering. Firstly, product is built up layer-by-layer by the selective deposition of a binder agent on a powder bed. Secondly, a thermal treatment (sintering) consolidates the metal structure. MBJ is currently becoming more and more attractive on the reason of high potential scalability, cost-effective production and wide range of available material feedstocks. However, the transition towards industrial scale production is restrained by the critical control of dimensional and geometrical precision of parts after sintering operation. In fact, product geometry is affected by anisotropic dimensional change or even shape distortion. This study aims at investigating the dimensional and geometrical precision of through holes. Three sample geometries were designed, having a through hole with axis perpendicular to the building direction and located at different levels along sample height. Samples were measured by a coordinate measuring machine before and after sintering, in order to assess the shrinkage and any shape change. Results highlight the inhomogeneous volumetric and linear shrinkage of the three geometries, which is influenced by the printing position in the building plane. A macroscopic deformation of parallelepiped geometry was also evidenced, caused by the superposition of layer shifting originated on printing, and by the frictional forces between sample surface and alumina support during sintering. Such distortion significantly affects the shrinkage and form error of holes.

The increase in pesticide consumption has a negative health impact. Studies point to an association between exposure to pesticides and cardiovascular disease (CVD), one of the leading causes of world mortality. This review synthesize evidence on the association between occupational exposure and environmental contamination by pesticides with CVDs from 1750 references databases (EBSCO, Medline, Science Direct, Scielo, Lilacs and Ovid) without date or language restriction. Selected 24 articles by PRISMA and DownsBlack methodologies, were included from inclusion criteria: original studies (case-control, cohort or cross-sectional design); clear CVD definition and exposure to pesticides; representative sample of the target population. The results show the occupational exposure to pesticides chlorpyrifos, coumafos, carbofuran, ethylene bromide, mancozeb, ziram, metalaxyl, pendimethalin and trifluralin was associated a risk of 1.8 to 3.2 for acute myocardial infarction. Primaphos, fenitrothion, malathion and deltamethrin pesticides were associated with a blood pressure increase. Environmental contamination by tetrachlorodibenzo-p-dioxin was associated with CVD with risk of 1.09 to 2.78 and organochlorine, 1.19 to 4.54; heavy metals, arsenic, trimethylarsine and dimethylarsinic acid with atherosclerosis and systemic arterial hypertension. These findings point to the association between exposure to pesticides and CVD, signaling the importance of greater rigor in the public policy related to pesticides.

This document presents an overview of the induced photocurrents in the Amorphous Silicon Position Detectors used in the network of diode lasers and photo sensors of the CMS Link alignment system recorded during its eleven years of operation. After a description of the sensors characteristics, the layout of the sensors network is discussed. The sensors are distributed throughout the muon spectrometer and connected by laser lines. The data used correspond to readout information obtained during some of the physics runs from 2008 to 2018.

Vanadium redox flow battery technology can support the spread of energy storage in stationary applications and allow higher penetration of renewables in the electric grid. Currently, its market competitiveness is hindered by low power density, which stems from complex interplay between kinetic and mass transport losses. The quantitative interpretation of experimental observations should rely on physics-based models, which allow a consistent comparison of different operative conditions. In this work, a fast analytical physics-based 1D model of the impedance of vanadium flow battery is presented and validated with respect to experimental data. The model, made available online at http://mrtfuelcell.polimi.it, employs a macro-homogeneous approach and considers losses due to kinetics, reactant distribution within the electrode (Sigracet® SGL 39 AA carbon paper), convection in flow channel and vanadium transport to electrode surface. Additionally, analytical expressions of contributions to impedance of single physical phenomena are derived through an asymptotical analysis. The results show that, at negative electrode, transport of ions to active surface is the limiting phenomenon at lower flow rates, while at higher flow rates depletion of reactants within electrode becomes critical together with charge transfer processes. At positive electrode, the main contribution to performance loss is the vanadium transport to electrode surface.

Homogeneous distribution of the electrolyte over the porous electrode is a critical issue hindering the commercialization of vanadium redox flow batteries, owing to increased overpotential at high current and limited power density of the system. Therefore, an understanding of the physical phenomena regulating mass transport of the electrolyte is crucial to improving system performance. The present work describes the development and experimental validation of a 3D computational fluid dynamic model of a vanadium redox flow battery in a half-cell configuration with an active area of 25 cm2. The model simulates the influence of a single serpentine and an interdigitated flow field. The adoption of the half-cell configuration allows the negative electrode to be considered as a pseudo-reference electrode with zero potential loss, leading to a reduction in computation time and the number of fitting parameters, which can be determined with reduced uncertainty. The developed model includes a traditional fluid dynamic analysis of the electrolyte in the flow field and in the porous electrode, coupled with the electrochemistry of the reactions involved. In both the experiments and the simulations, the single serpentine distributor exhibits better performance and higher pressure drops compared to those of the interdigitated geometry under all the investigated operating conditions. In the analysis of the local reaction rate, both distributors experienced increased reaction rates under the rib, induced by a by-pass flow between adjacent channels. The reaction rate shows a highly heterogeneous distribution in the serpentine geometry, while it is more uniform in the interdigitated configuration.

Degradation of catalyst electrochemical active surface is a major issue that hinders polymer electrolyte fuel cells commercialization. Several degradation mechanisms that have been reported in the literature are known to result in heterogeneity of ageing, whose effects on performance loss have not been previously investigated. In this work experimental and theoretical methodologies are combined to provide an insight between the effects of heterogeneity of ageing and the evolution of electrochemical impedance spectra. Experimental results collected during a 6000 hours degradation test indicate an increase of cathode charge transfer and mass transport resistances, consistently with cyclic voltammetry that reveals about 60% loss of cathode catalyst active surface. A physical based model is developed and validated to demonstrate that uniform cathode ageing does not to affect the evolution of impedance spectra. On the other side, it is shown that non-uniform ageing of cathode active area improves the agreement with experimental data. The evolution of the polarization curves and impedance spectra recorded during 6000 hours degradation test is critically discussed by including heterogeneity of ageing.

Due to an error in production the members of SICE CoDIG (Colon Dx Italian Group) listed in the Acknowledgments were not tagged correctly as authors in the XML of this article. This listing is presented again here:.

Reduced power density is one of the main critical issues of vanadium redox flow batteries and it is mainly due to critical electrolyte distribution over the porous electrodes and sluggish kinetics. Therefore, it is crucial to elucidate the interplay between morphological and electrochemical features of carbon electrodes and their influence on battery performance. In this work, three considerably different carbon electrodes were characterized in order to highlight the most relevant electrode properties governing system operation, distinguishing between positive and negative electrode performance, that are differently affected by kinetic and mass transport losses, especially at local level. Scanning electron microscopy and Raman spectroscopy provided insights on the electrodes structure, while mercury intrusion porosimetry and thermogravimetric analyses permitted to evaluate porous volume, surface area, skeletal density and pores diameter. Local electrochemical characterization was performed by means of through-plate hydrogen reference electrodes: innovative in-situ cyclic voltammetry allowed to decouple electrode operation from fluid-dynamic phenomena, whose influence on battery performance was evaluated with polarization curves at different flow rates. The best electrode design is the result of a proper combination between high surface area and pores diameter, that on one hand has to be sufficiently large to promote electrolyte permeation from distribution channel, but on the other hand has to be small to reduce mass transport losses at pore scale. The negative electrode performance is strongly affected by kinetic losses, while the operation of positive electrode is mainly influenced by mass transport phenomena.

Methanol crossover is one of the most critical issues hindering commercialization of direct methanol fuel cells since it leads to waste of fuel and significantly affects cathode potential, forming a so-called mixed potential. Unfortunately, due to the sluggish anode kinetics, it is not possible to obtain a reliable estimation of cathode potential by simply measuring the cell voltage. In this work we address this limitation, quantifying the mixed potential by means of innovative open circuit voltage (OCV) tests with a methanol-hydrogen mixture fed to the anode. Over a wide range of operating conditions, the resulting cathode overpotential is between 250 and 430 mV and is strongly influenced by methanol crossover. We show using combined experimental and modelling analysis of cathode impedance that the methanol oxidation at the cathode mainly follows an electrochemical pathway. Finally, reference electrode measurements at both cathode inlet and outlet provide a local measurement of cathode potential, confirming the reliability of the innovative OCV tests and permitting the evaluation of cathode potential up to typical operating current. At 0.25 A cm −2 the operating cathode potential is around 0.85 V and the Ohmic drop through the catalyst layer is almost 50 mV, which is comparable to that in the membrane.

Magnet Cycles and Stability Periods of the CMS Experiment are studied with the Alignment Link System data recorded along the 2008-2013 years of operation. The motions of the mechanical structures due to the magnetic field forces are studied and the mechanical stability of the detector during the physics data taking periods is verified.

Capacity loss induced by the undesired transport of vanadium ions across the ion-exchange membrane (i.e. crossover) is one of the most critical issues associated with vanadium redox flow batteries. This work reports on the manufacturing and testing of an innovative barrier layer to mitigate crossover. The barrier layer conceptual design is described in detail in the patent application WO 2019/197917. The barrier was deposited directly onto Nafion® 212 using the Reactive Spray Deposition Technology, in which carbon-rich particles (∼4–10 nm in diameter) formed in the flame were deposited simultaneously with a mixture of 1100EW Nafion® and Vulcan® XC-72R (∼40 nm diameter) that was sprayed from air-assisted secondary nozzles. During cycles at fixed capacity, the presence of the barrier layer significantly reduced battery self-discharge; the average variation of battery state of charge compared to a reference cell with Nafion® 115 was reduced from 21% to 7%. Moreover, battery energy efficiency was increased by nearly 5%, indicating that the barrier layer does not significantly hinder proton transport. During cycles at 50 mA cm−2 with fixed cut-off voltages, the barrier layer exhibited stable operation, maintaining a coulombic efficiency around 99.4%. Additionally, the use of the barrier layer projects to a 30% reduction of stack-specific cost.

Unrecoverable and recoverable performance degradation is a major issue hindering commercialization of polymer electrolyte membrane fuel cells. The recoverable losses, caused for example by a contaminant adsorption, catalyst flooding, ionomer dehydration, and platinum oxidation, can be reversed, usually following an interruption in the cell operation. In order to elucidate the link between platinum oxidation and recoverable performance loss, three MEAs were characterized in this work. They involved catalysts with different nanoparticle sizes and loadings tested using a combination of the electrochemical impedance spectroscopy, constant-voltage, constant-current and potential controlled techniques, before and after electrocatalyst aging. Experimental results indicate that a decrease in specific activity over time is not affected by nanoparticle size or aging. Nevertheless, linear sweep voltammetry, which is adopted to reduce platinum oxide and as diagnostics for oxide composition, reveals that a change in composition is observed in correlation with catalyst morphology and catalyst aging. The formation of the platinum oxide associated with the peak at 0.61 VRHE in the voltammetry is found to decrease the catalyst's specific activity more than oxides associated with peaks at higher potentials. This indicates that the recoverable performance loss due to the platinum oxide formation depends on the oxide composition.

The inhomogeneous distribution of electrolyte over the porous electrode is one of the main issues hindering vanadium flow battery performance, limiting the system power density. Moreover, the interplay between fluid dynamics in distribution channels and morphology of porous electrodes is not well understood at local level throughout the cell active area, where local reactant starvation may occur and further limit system performance. Therefore, a systematic local characterization is fundamental to improve the understanding of system operation and to enhance system power density. This work discusses the implementation of a 10 regions macro-segmented flow battery with 25 cm2 active area, that permits the local measurement of polarisation curves and impedance spectra. Both positive and negative symmetric cells, as well as all-vanadium configuration, are adopted, combining carbon paper electrodes of different thickness with single serpentine and interdigitated distributors. The characterization evidences that single serpentine presents poor performance towards cell outlet, while interdigitated geometry is limited in the central region of active area. In most of the investigated operating conditions, single serpentine induces a more heterogeneous operation, especially if coupled with thinner electrode and positive electrolyte. Moreover, the representativeness at local level of symmetric cells compared to all-vanadium one is analysed and discussed.

This study investigated the antioxidant activity of

Durability issues of direct methanol fuel cell still hinder technology widespread commercialization; uneven aging of MEA components, generally harsher in air outlet region, is known to exasperate overall performance degradation. In a previous work, the authors selected a stable cathode electrode, demonstrated to fade homogenously: uneven water-related limitations, such as dehydration and flooding, were revealed to locally worsen performance at cathode inlet and outlet regions, leading to current redistribution. Aiming to reduce degradation rate, in this work homogeneous current distribution during operation is pursued by tuning MEA properties to meet local operating conditions. A properly improved 1D+1D physical model is used to support the development of a gradient MEA, featuring 1.6 mg cm−2 and 0.8 mg cm−2 of catalyst and ionomer respectively at inlet/outlet and center regions of cathode electrode. Tests based on custom macro-segmented cell demonstrated 55% more homogeneous current distribution, controllable during operation by means of cathode air stoichiometry. 500 h degradation test revealed 70% decreased degradation rate from uniform MEA (11 μV h−1) with a homogenous fading of performance. An 18% lower Pt nanoparticle growth at cathode outlet and limited ionomer degradation at cathode inlet were identified by ex-situ analyses (TEM and XPS), indicating locally mitigated fading mechanisms.

Vanadium redox flow battery performance is actually hindered by increased overpotentials at high current, due to poor electrochemical activity of the most commonly used carbon electrodes and to electrolyte distribution, implying local mass transport limiting conditions. Moreover, vanadium cross-contamination leads to coulombic efficiency reduction and uncontrolled electrolytes imbalance. This work presents the application of through-plate reference electrodes at inlet and outlet of both positive and negative electrodes. The utility of the electrodes potential measurement is firstly demonstrated in the identification of a relation between electrolytes potential and the corresponding state of charge. Subsequently, local overpotentials and impedance spectra at both electrodes are evaluated, evidencing that the negative electrode is kinetically dominated and presents high overpotential even at low current, while the positive exhibits mass transport effects at high current, especially at cell outlet. Finally, during cycling operation with fixed capacity reference electrode measurements permit to monitor electrolytes imbalance induced by cross-contamination, that mainly affects negative electrolyte. Moreover, additional insights into electrodes potential loss during cycling are provided.

The central feature of the CMS Link alignment system is a network of Amorphous Silicon Position Detectors distributed throughout the muon spectrometer that are connected by multiple laser lines. The data collected during the years from 2008 to 2015 is presented confirming an outstanding performance of the photo sensors during more than seven years of operation. Details of the photo sensor readout of the laser signals are presented. The mechanical motions of the CMS detector are monitored using these photosensors and good agreement with distance sensors is obtained., Open Access funded by CERN.

The study deals with the investigation of a sol–gel/nanoclay composite coating as a protective layer for the corrosion protection of hot dip galvanized (HDG) steel. Sol–gel coatings prepared from glycidoxypropyltrimethoxysilane, tetraethoxysilane and methyltriethoxysilane with 2 wt.% of sodium montmorillonite were investigated. The effect of different curing times (2, 5, 10, 15 min) and different curing temperatures (90 °C, 150 °C, 180 °C) on the protection properties of the hybrid layer was investigated. ToF-SIMS analyses and FT-IR measurements highlighted that the higher is the curing temperature, the higher is the densification of the sol–gel network. FT-IR spectroscopy measurements underlined that the Si O Si/Si OH ratio rises by increasing curing time or temperature. ToF-SIMS analyses indicate a lessening in the coating thickness by increasing the curing temperature. The densification of the network through formation of siloxane bonds was found to be responsible for the improved protection offered by the sol–gel layer which leads to a remarkable drop of the cathodic current density and an increase of the resistance associated to the sol–gel film.

Haemophilia is an inherited haemorrhagic disease characterized by the lack of coagulative factors associated nowadays mostly to musculoskeletal complications, particularly severe secondary arthritis in specific joints. Recurrent traumatic or spontaneous joint bleeding, induce severe arthropathy at a young age that can be treated only by joint replacement. Total knee or hip arthroplasty in young subjects may fail earlier due to wear or infections and in the haemophilic population, this means bone loss, pseudo tumours and the need of revision or even limb salvage surgery. Modern modular implants and the use of bone graft enriched by tissue engineering techniques such as a concentration of autologous mesenchymal cells or PRP may be helpful to compensate all bone loss and anatomic alterations due to failures of orthopaedic implants. The authors present their experience with this type of surgery and their biological approach to these challenging cases.

The DMFC is a promising option for backup power systems and for the power supply of portable devices. However, from the modeling point of view liquid-feed DMFC are challenging systems due to the complex electrochemistry, the inherent two-phase transport and the effect of methanol crossover. In this paper we present a physical 1D cell model to describe the relevant processes for DMFC performance ranging from electrochemistry on the surface of the catalyst up to transport on the cell level. A two-phase flow model is implemented describing the transport in gas diffusion layer and catalyst layer at the anode side. Electrochemistry is described by elementary steps for the reactions occurring at anode and cathode, including adsorbed intermediate species on the platinum and ruthenium surfaces. Furthermore, a detailed membrane model including methanol crossover is employed. The model is validated using polarization curves, methanol crossover measurements and impedance spectra. It permits to analyze both steady-state and transient behavior with a high level of predictive capabilities. Steady-state simulations are used to investigate the open circuit voltage as well as the overpotentials of anode, cathode and electrolyte. Finally, the transient behavior after current interruption is studied in detail.

Mass transport of the electrolyte over the porous electrode is one of the most critical issues hindering Vanadium Redox Flow Battery commercialization, leading to increased overpotential at high current and limiting system power density. In this work, a 1D physically based impedance model of Vanadium Redox Flow Battery negative electrode is developed, taking into account electrochemical reactions, convection at carbon fiber, diffusion in the pores and migration and diffusion through electrode thickness. The model is validated with respect to experimental data measured in a symmetric cell hardware, which allows to keep the State of Charge constant during the measurement. The physically based approach permits to elucidate the origin of different impedance features and quantify the corresponding losses. Charge transfer resistance decreases with increasing current and is generally lower compared to the ones related to mass transport phenomena. Migration losses through the porous electrode are negligible, while convection at carbon fiber is relevant and in Nyquist plot results in a linear branch at low frequency. In presence of significant convection losses the reaction tends to concentrate close to the channel: this leads to a reduction of diffusion losses through the electrode, while diffusion process in the pores becomes more limiting.

Electrochemical impedance spectroscopy is a widely recognized tool for in situ diagnostics of polymer fuel cells. The main drawback of this measurement is that it includes several features, which are not directly related to physical phenomena and the interpretation is often difficult. In this work, a physical quasi 2D model is applied to experimental data of a high temperature proton exchange fuel cell based on polybenzimidazole doped with phosphoric acid. The quasi 2D approach is applied in order to decrease the computational cost of the model, without decreasing the prediction capability. The model is able to simulate polarization curves and impedance spectra and it is fitted on six polarization data and impedance spectra recorded in different conditions. The model is able to capture the main features of a typical spectrum of a polybenzimidazole based high temperature polymer fuel cell. A sensitivity analysis is also performed on the model parameters to show the effect of each physical parameter.

In the present work a physically based model of direct methanol fuel cell anode impedance has been developed and validated at different operating current densities. The proposed model includes the two-phase mass transport of both methanol and water through diffusion and catalyst layers and the methanol oxidation reaction involving CO adsorbed intermediate. Model simulations are in good quantitative agreement with experimental observations and permit to evaluate the origin of anode impedance features. Model results confirm that the high frequency 45° linear branch is caused by proton transport limitations within the catalyst layer and that the low frequency inductive behavior is due to surface coverage by CO reaction intermediate. Moreover model predictions elucidate the contribution to the impedance of mass transport phenomena through diffusion layer, that is relevant even at low current density and increases along the channel length. In particular liquid convective fluxes are considered as a process of pressure buildup and breakthrough at diffusion layer intersecting fibers, resulting in a discontinuous phenomenon. By means of this intermittent description it is possible to correctly reproduce mass transport limitations through diffusion layers, that manifest themselves as a second arch superimposed to the first one, peculiar of kinetic losses.

Degradation is one of the critical issues of direct methanol fuel cells. The experimental investigations found in the literature show that degradation has both permanent and temporary contributions. The latter can be recovered after operation interruption, but its origins are not fully understood. This work aims to investigate the anodic degradation by measuring the anode overpotential setting the cathode as a dynamic hydrogen electrode. Experimental degradation tests are performed in cycling operation, which consists in cycles of 20 min of continuous operation at constant current and a variable number of minutes at OCV. Experimental results show that the anode overpotential decreases after OCV period, demonstrating the existence of anode temporary degradation. Moreover the temporary contribution is strongly affected by the duration of OCV period: long operation interruption lowers temporary degradation. From the interpretation of impedance spectra, it is reasonable to attribute the anode temporary degradation mainly to the dehydration of the anode electrode and the reduction of methanol concentration due to CO2 accumulation that determines a gas diffusion layer and electrode saturation reduction. Instead hydrogen crossover from cathode to anode has a negligible effect. Finally, a physical model of anode impedance is used to support the proposed origins of anode temporary degradation.

Arce, Pedro et al., A study of the time required for the CMS detector to reach structural equilibrium once the magnetic field is ramped to its operational value of 3.8 T is presented. In addition, the results from a stability monitoring at 3.8 T over an eight-month period are given. © 2012 Elsevier B.V. All rights reserved.

The primary energy consumption in residential buildings is determined by the envelope thermal characteristics, air change, outside climatic data, users’ behaviour and the adopted heating system and its control. The new Italian regulations strongly suggest the installation of centralized boilers in renovated buildings with more than four apartments. This work aims to investigate the differences in primary energy consumption and efficiency among several independent and centralized heating systems installed in Northern Italy. The analysis is carried out through the following approach: firstly building heating loads are evaluated using the software TRNSYS ® and, then, heating system performances are estimated through a simplified model based on the European Standard EN 15316. Several heating systems have been analyzed, evaluating: independent and centralized configurations, condensing and traditional boilers, radiator and radiant floor emitters and solar plant integration. The heating systems are applied to four buildings dating back to 2010, 2006, 1960s and 1930s. All the combinations of heating systems and buildings are analyzed in detail, evaluating efficiency and primary energy consumption. In most of the cases the choice between centralized and independent heating systems has minor effects on primary energy consumption, less than 3%: the introduction of condensing technology and the integration with solar heating plant can reduce energy consumption by 11% and 29%, respectively.

From May 2007 to March 2008, blood samples were collected from 92 healthy dogs living in 21 households (17 farms in rural area, and 4 homes in urban area) in 6 counties of the State of Espírito Santo, southeastern Brazil. In addition, ticks were collected from these dogs. A mean of 4.4+/-3.0 dogs (range: 1-12) were sampled per household; 78 and 14 dogs were from rural and urban areas, respectively. Polymerase chain reaction (PCR) designed to amplify fragments of the 18S rDNA gene of Babesia spp or Hepatozoon spp revealed amplicons of the expected size in 20 (21.7%) dogs for Babesia, and 54 (58.7%) dogs for Hepatozoon. All Babesia-positive dogs were also Hepatozoon-positive. Among the 21 households, 15 (71.4%) from 3 counties had at least one PCR-positive dog, including 13 farms (rural area) and 2 homes (urban area). A total of 40 PCR products from the Hepatozoon-PCR, and 19 products from the Babesia-PCR were submitted to DNA sequencing. All generated sequences from Hepatozoon-PCR were identical to each other, and to corresponding 18S rDNA sequences of H. canis in GenBank. Surprisingly, all generated sequences from the Babesia PCR were also identical to corresponding 18S rDNA sequences of H. canis in GenBank. Dogs from 10 rural and 2 urban households were found infested by Rhipicephalus sanguineus ticks. Immature of Amblyomma cajennense ticks were found in dogs from only 4 rural households (also infested by R. sanguineus). All but one household with R. sanguineus-infested dogs had at least one Hepatozoon-infected dog. Statistical analysis showed that the presence of ticks (i.e. R. sanguineus) infesting dogs in the households was significantly (P0.05) associated with at least one PCR-positive dog. There was no significant association (P0.05) between PCR-positive dogs and urban or rural households. Canine hepatozoonosis caused by H. canis is a high frequent infection in Espírito Santo, Brazil, where it is possibly vectored by R. sanguineus. Since all infected dogs were found apparently healthy, the pathogenicity of H. canis for dogs in Espírito Santo is yet to be elucidated.

This document describes results obtained from the Link alignment system data recorded during the Compact Muon Solenoid (CMS) Magnet Test. A brief description of the system is followed by a discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotations of detector structures (from microradians to milliradians). Observed displacements are studied as functions of the magnetic field intensity. In addition, the reconstructed positions of active element sensors are compared to their positions as measured by photogrammetry and the reconstructed motions due to the magnetic field strength are described.

The intracellular signaling mechanisms underlying the pathogenesis of cardiac diseases are not fully understood. We report here that selective deletion of Shp2, an SH2-containing cytoplasmic tyrosine phosphatase, in striated muscle results in severe dilated cardiomyopathy in mice, leading to heart failure and premature mortality. Development of cardiomyopathy in this mouse model is coupled with insulin resistance, glucose intolerance, and impaired glucose uptake in striated muscle cells. Shp2 deficiency leads to upregulation of leukemia inhibitory factor-stimulated phosphatidylinositol 3-kinase/Akt, Erk5, and Stat3 pathways in cardiomyocytes. Insulin resistance and impaired glucose uptake in Shp2-deficient mice are at least in part due to impaired protein kinase C-zeta/lambda and AMP-kinase activities in striated muscle. Thus, we have generated a mouse line modeling human patients suffering from cardiomyopathy and insulin resistance. This study reinforces a concept that a compound disease with multiple cardiovascular and metabolic disturbances can be caused by a defect in a single molecule such as Shp2, which modulates multiple signaling pathways initiated by cytokines and hormones.

Expression of the NR3A subunit with NR1/NR2 in Xenopus oocytes or mammalian cell lines leads to a reduction in N-methyl-d-aspartate (NMDA)-induced currents and decreased Mg2+ sensitivity and Ca2+ permeability compared with NR1/NR2 receptors. Consistent with these findings, neurons from NR3A knockout (KO) mice exhibit enhanced NMDA-induced currents. Recombinant NR3A can also form excitatory glycine receptors with NR1 in the absence of NR2. However, the effects of NR3A on channel properties in neurons and synaptic transmission have not been fully elucidated. To study physiological roles of NR3A subunits, we generated NR3A transgenic (Tg) mice. Cultured NR3A Tg neurons exhibited two populations of NMDA receptor (NMDAR) channels, reduced Mg2+ sensitivity, and decreased Ca2+ permeability in response to NMDA/glycine, but glycine alone did not elicit excitatory currents. In addition, NMDAR-mediated excitatory postsynaptic currents (EPSCs) in NR3A Tg hippocampal slices showed reduced Mg2+ sensitivity, consistent with the notion that NR3A subunits incorporated into synaptic NMDARs. To study the function of endogenous NR3A subunits, we compared NMDAR-mediated EPSCs in NR3A KO and WT control mice. In NR3A KO mice, the ratio of the amplitudes of the NMDAR-mediated component to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-mediated component of the EPSC was significantly larger than that seen in WT littermates. This result suggests that NR3A subunits contributed to the NMDAR-mediated component of the EPSC in WT mice. Taken together, these results show that NR3A subunits contribute to NMDAR responses from both synaptic and extrasynaptic receptors, likely composed of NR1, NR2, and NR3 subunits.

Polymer Electrolyte Membrane Fuel Cell (PEMFC) based systems have recently received increasing attention as a viable alternative for meeting the residential electrical and thermal demands. However, as the intermittent demand profiles of a building can only be addressed by a tri-generative unit which can operate at partial loads, the variation of performance of the system at partial loads might affect its corresponding potential benefits significantly. Nonetheless, no previous study has been carried out on assessing the performance of this type of tri-generative systems in such conditions. The present paper is the first of a two part study dedicated to the investigation of the performance of a tri-generative system in which a PEMFC based system is coupled with a desiccant wheel unit. This study is focused on evaluating the performance of the PEMFC subsystem while operating at partial loads. Accordingly, a detailed mathematical model of the fuel cell subsystem is first developed and validated using the experimental data obtained from the plant’s and the fuel cell stack’s manufacturer. Next, in order to increase the performance of the plant, two modifications have been proposed and the resulting performance at partial load have been determined. The obtained results demonstrate that applying both modifications results in increasing the electrical efficiency of the plant by 5.5%. It is also shown that, while operating at partial loads, the electrical efficiency of the plant does not significantly change; the fact which corresponds to the trade-off between the increment in the gross electrical efficiency and the lower slope of decrement in the auxiliary losses. The obtained results are suitable to be employed to assess the performance of the overall tri-generative system, conducted in the second part of the study, while meeting intermittent load profiles.

Performance degradation is one of the key issues hindering direct methanol fuel cell commercialization, caused by different mechanisms interplaying locally and resulting in both temporary and permanent contributions. This work proposes a systematic experimental investigation, coupling in-situ diagnostics (electrochemical and mass transport investigation) with ex-situ analyses of pristine, activated and aged components (X-ray photoelectron spectroscopy and transmission electron microscopy), with an in-plane and through-plane local resolution. Such a combined approach allows to identify on one hand the degradation mechanisms, the affected components and the presence of heterogeneities; on the other hand, it allows to quantify the effect of the major mechanisms on performance decay. Thanks to a novel procedure, temporary (21 μV h−1) and permanent degradation (59 μV h−1) are separated, distinguishing the latter in different contributions: the effects of active area loss at both at anode (9 μV h−1) and cathode (31 μV h−1), mass transport issue (15 μV h−1) and membrane decay (4 μV h−1). The post-mortem analysis highlights the effect of degradation mechanisms consistent with the in-situ analysis and reveals the presence of considerable in plane and through plane heterogeneities in: particle size growth in catalyst layers, Pt/Ru and polymer content in catalyst and diffusion layers, Pt/Ru precipitates in the membrane.

Background A patient with Waldenstrom's macroglobulinemia was admitted to the hospital with fever, leg pain, and dyspnea. The patient had gas gangrene of the left leg that required above-the-knee amputation. Plasmapheresis was instituted to treat hyperviscosity. Study design and methods The patient's serum contained an IgM-kappa paraprotein, a cryoglobulin, and a cold agglutinin. The serum was studied. Results The patient's red cells typed as A1, Rh-positive. The direct antiglobulin test was negative. The serum contained a cold agglutinin with anti-Pr cold agglutinin specificity (titer 4096). Maximal thermal range was 30 degrees C. Following dithiothreitol treatment, the cold agglutinin activity disappeared. The serum IgM concentration in the tested sample was 62.3 g per L. The cold agglutinin titer in the supernatant after removal of the cryoglobulin was 256, and the IgM level was 0.31 g per L. Redissolving the cryoglobulin in a equivalent volume of saline resulted in a cold agglutinin titer of 4096 and an IgM level of 68.4 g per L. These results indicate that the cryoglobulin and the cold agglutinin are the same paraprotein. Serum protein electrophoresis using agarose gel and immunofixation of the serum revealed an IgM-kappa monoclonal band. Progenitor cell assays were performed by adding the patient's serum at final concentrations of 0, 1, 5 and 10 percent (vol/vol) to patient's and normal donor's peripheral blood mononuclear cells. Inhibition of burst-forming units-erythroid and colony-forming units-granulocyte/macrophage by the patient's serum was demonstrated. Appropriate controls and the use of the serum of another patient with Waldenstrom's macroglobulinemia did not suppress progenitor cell growth. The patient's serum inhibited colony formation in a dose-response fashion. Conclusion Reports of cryoprecipitable cold agglutinins are rare. This case is unusual because the IgM-kappa paraprotein was also a cold agglutinin with anti-Pr specificity and erythroid and granulocyte-macrophage progenitor cell-suppressive properties.

In mammals, the most important synchronizer for endogenous rhythms is the environmental light/dark cycle. In this report we have explored the ability of light/dark cycle and melatonin, the pineal hormone released during the night, to modulate cerebellar cholinergic input by interfering with the nicotinic acetylcholine receptors' (nAChRs) availability. Through the analysis of the response to selective cholinergic agonists and antagonists, we observed that nAChRs containing the alpha7 gene product mediate the release of [(3)H]glutamate from rat cerebellum slices. The [(3)H]glutamate overflow induced by alpha7 nAChR activation was higher during the dark phase, although the number of alpha-[(125)I]bungarotoxin binding sites, but not the [(3)H]nicotine binding sites (B(max)), was reduced. On the other hand, glutamate-evoked [(3)H]glutamate release was not modified by the hour of the day. Finally, we show that the nocturnal increase in nicotine-evoked [(3)H]glutamate release is imposed by a nocturnal surge of melatonin, as it is abolished when pineal melatonin production is inhibited by either maintaining the animals in constant light for 48 h or by injecting propranolol just before lights off for 2 days. The difference between light and dark [(3)H]glutamate-evoked release is restored in propranolol-treated animals that received melatonin during the dark period. In conclusion, we show that nicotine-evoked [(3)H]glutamate release in rat cerebellum presents a diurnal variation, driven by nocturnal pineal melatonin surge.

A high voltage generator built by a series connection of 100 kV modules was produced. The series connection feasibility is ensured by the inherent floating character of each module which is wireless powered by high efficiency photovoltaic cells illuminated by a laser system. Each module is equipped with a control and monitoring board allowing excellent stabilization of the high voltage output. The performance of the system in terms of reliability, stability, and efficiency was evaluated. In particular using a three module setup, we achieved a maximum voltage of 234 kV with stability better than 0.1%.

O objetivo desta revisao foi atualizar a evolucao da producao cientifica em epidemiologia da atividade fisica no Brasil. Tambem buscamos verificar a distribuicao geografica das pesquisas e a evolucao do conhecimento conforme os principais dominios que caracterizam a pesquisa em atividade fisica e saude. Foi realizada uma busca sistematica da literatura nas bases de dados PubMed, LILACS e SciELO, alem de buscas manuais por autores e referencias cruzadas. Artigos originais publicados entre 2005 e 2013 foram incluidos contendo um ou mais dominios da atividade fisica, conhecimento sobre atividade fisica e/ou comportamento sedentario, com amostra igual ou maior a 500 participantes. Apos a sintese descritiva, os estudos foram estratificados conforme localizacao geografica, delineamento e dominios de pesquisa na area da atividade fisica e saude. A analise final foi feita com 276 estudos. Os dados obtidos demonstraram crescente publicacao cientifica brasileira na area de epidemiologia da atividade fisica (de 7 para 49 artigos/ano), sendo 82,2% delineados para analisar os determinantes, niveis e tendencias temporais e as consequencias a saude da pratica regular da atividade fisica e/ou do prolongamento do comportamento sedentario. No plano regional, houve concentracao das pesquisas nas regioes Sul (43,5%) e Sudeste (22,1%) do pais e crescimento das publicacoes provindas da regiao Nordeste (18,5%), e dos trabalhos com representatividade nacional, ou que envolvem cidades de regioes distintas (12,3%). Foi evidenciada grande evolucao no numero de publicacoes brasileiras em epidemiologia da atividade fisica, apesar de importantes limitacoes regionais, tipo de delineamento utilizado e dos dominios de pesquisa desenvolvidos.