In situ monitoring of electroactive species by using voltammetry at microelectrodes

Mercury coated platinum microelectrodes were employed for the in situ determination, in soils and porewater of sediments, of redox key species of environmental interest. Sand samples were considered as soil model for the in situ detection of oxygen. Direct measurements of sulphide were performed in anoxic sediments collected in the Lagoon of Venice. An investigation on the interaction among heavy metals, sulphide and solid particles in pore-water extracted from the sediments was also performed. For the quantification of the various electroactive species examined, calibrantioless procedures were employed. Usou-se microeletrodos de platina recobertos de mercúrio, em solo e águas sedimentares, para a determinação in situ de espécies "redox", de importância ambiental. Amostras de areia foram consideradas como o modelo para solos, na detecção in situ de oxigênio. Medidas diretas de sulfeto foram realizadas em sedimentos anóxidos coletados nos lagos de Veneza. Uma investigação da interação entre metais pesados, sulfeto e partículas sólidas em água corrente, extraídos dos sedimentos, também foi feita. A quantificação das várias espécies eletroativas examinadas, foi feita por procedimentos sem necessidade de calibração

Acquiring, archiving, analyzing and exchanging seismic data in real time at the Seismological Research Center of the OGS in Italy

After the 1976 Friuli earthquake (Ms = 6.5) in north-eastern Italy that caused about 1,000 casualties and widespread destruction in the Friuli area, the Italian government established the Centro di Ricerche Sismologiche (CRS). This is now a department of the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), and it is specifically devoted to the monitoring of the seismicity of north-eastern Italy. Since its inception, the North-East Italy Seismic Network has grown enormously. Currently, it consists of 14 broad-band and 20 short-period seismic stations, all of which are telemetered to and acquired in real time at the OGS-CRS data center in Udine. Data exchange agreements in place with other Italian, Slovenian, Austrian and Swiss seismological institutes lead to a total number of 94 seismic stations acquired in real time, which confirms that the OGS is the reference institute for seismic monitoring of north-eastern Italy. Since 2002, CRS has been using the Antelope software suite as the main tool for collecting, analyzing, archiving and exchanging seismic data. SeisComP is also used as a real-time data exchange server tool. A customized web accessible server is used to manually relocate earthquakes, and automatic procedures have been set-up for moment-tensor determination, shaking-map computation, web publishing of earthquake parametric data, waveform drumplots, state-of-health parameters, and quality checks of the station by spectra analysis. Scripts for email/SMS/fax alerting to public institutions have also been customized. Recently, a real-time seismology website was designed and set-up (http://rts.crs.inogs.it/)

A novel PNPLA2 mutation causing total loss of RNA and protein expression in two NLSDM siblings with early onset but slowly progressive severe myopathy

Neutral lipid storage disease with myopathy (NLSDM) is a rare autosomal recessive disorder, due to an enzymatic error of lipid metabolism. Patients present always with skeletal muscle myopathy and variable cardiac and hepatic involvement. NLSDM is caused by mutations in the PNPLA2 gene, which encodes the adipose triglyceride lipase (ATGL). Here we report the molecular characterization and clinical findings of two NLSDM siblings carrying the novel c.187+1G > C homozygous PNPLA2 mutation, localized in the splice site of intron 2. Molecular analyses revealed that neither aberrant PNPLA2 mRNA isoforms, nor ATGL mutated protein were detectable in patient's cells. Clinically, both patients presented early onset muscle weakness, in particular of proximal upper limb muscles. In almost 15 years, muscle damage affected also distal upper limbs. This is a NLSDM family, displaying a severe PNPLA2 mutation in two siblings with clinical presentation characterized by an early onset, but a slowly evolution of severe myopathy

Zebrafish as a Model to Investigate Dynamin 2-Related Diseases

Mutations in the dynamin-2 gene (DNM2) cause autosomal dominant centronuclear myopathy (CNM) and dominant intermediate Charcot-Marie-Tooth (CMT) neuropathy type B (CMTDIB). As the relation between these DNM2-related diseases is poorly understood, we used zebrafish to investigate the effects of two different DNM2 mutations. First we identified a new alternatively spliced zebrafish dynamin-2a mRNA (dnm2a-v2) with greater similarity to human DNM2 than the deposited sequence. Then we knocked-down the zebrafish dnm2a, producing defects in muscle morphology. Finally, we expressed two mutated DNM2 mRNA by injecting zebrafish embryos with human mRNAs carrying the R522H mutation, causing CNM, or the G537C mutation, causing CMT. Defects arose especially in secondary motor neuron formation, with incorrect branching in embryos injected with CNM-mutated mRNA, and total absence of branching in those injected with CMT-mutated mRNA. Muscle morphology in embryos injected with CMT-mutated mRNA appeared less regularly organized than in those injected with CNM-mutated mRNA. Our results showing, a continuum between CNM and CMTDIB phenotypes in zebrafish, similarly to the human conditions, confirm this animal model to be a powerful tool to investigate mutations of DNM2 in vivo

Magnetic Moments and Electron Transport through Chromium-Based Antiferromagnetic Nanojunctions

We report the electronic, magnetic and transport properties of a prototypical antiferromagnetic (AFM) spintronic device. We chose Cr as the active layer because it is the only room-temperature AFM elemental metal. We sandwiched Cr between two non-magnetic metals (Pt or Au) with large spin-orbit coupling. We also inserted a buffer layer of insulating MgO to mimic the structure and finite resistivity of a real device. We found that, while spin-orbit has a negligible effect on the current flowing through the device, the MgO layer plays a crucial role. Its effect is to decouple the Cr magnetic moment from Pt (or Au) and to develop an overall spin magnetization. We have also calculated the spin-polarized ballistic conductance of the device within the Buttiker-Landauer framework, and we have found that for small applied bias our Pt/Cr/MgO/Pt device presents a spin polarization of the current amounting to similar or equal to 25%

Quantitative localized proton-promoted dissolution kinetics of calcite using scanning electrochemical microscopy (SECM)

Scanning electrochemical microscopy (SECM) has been used to determine quantitatively the kinetics of proton-promoted dissolution of the calcite (101̅4) cleavage surface (from natural “Iceland Spar”) at the microscopic scale. By working under conditions where the probe size is much less than the characteristic dislocation spacing (as revealed from etching), it has been possible to measure kinetics mainly in regions of the surface which are free from dislocations, for the first time. To clearly reveal the locations of measurements, studies focused on cleaved “mirror” surfaces, where one of the two faces produced by cleavage was etched freely to reveal defects intersecting the surface, while the other (mirror) face was etched locally (and quantitatively) using SECM to generate high proton fluxes with a 25 μm diameter Pt disk ultramicroelectrode (UME) positioned at a defined (known) distance from a crystal surface. The etch pits formed at various etch times were measured using white light interferometry to ascertain pit dimensions. To determine quantitative dissolution kinetics, a moving boundary finite element model was formulated in which experimental time-dependent pit expansion data formed the input for simulations, from which solution and interfacial concentrations of key chemical species, and interfacial fluxes, could then be determined and visualized. This novel analysis allowed the rate constant for proton attack on calcite, and the order of the reaction with respect to the interfacial proton concentration, to be determined unambiguously. The process was found to be first order in terms of interfacial proton concentration with a rate constant k = 6.3 (± 1.3) × 10–4 m s–1. Significantly, this value is similar to previous macroscopic rate measurements of calcite dissolution which averaged over large areas and many dislocation sites, and where such sites provided a continuous source of steps for dissolution. Since the local measurements reported herein are mainly made in regions without dislocations, this study demonstrates that dislocations and steps that arise from such sites are not needed for fast proton-promoted calcite dissolution. Other sites, such as point defects, which are naturally abundant in calcite, are likely to be key reaction sites

Roles of pathway-based models and their contribution to the redesign of health-care systems

Care pathways provide a practical analytical tool that encompasses both organizational efficiency and individual patients'care. In the UK, constructing the care pathway has been a recommended starting point for the re-design of health-caresystems. This paper examines the re-design cycle for health-care systems and looks at the role of pathway-basedmodels in the design and operation phases of the cycle. In addition, the models provide further benefits for communicatingrecommended practice and audit of care and outcomes. The models span the classic care pathway with extensions tosimulation modelling. An example of the use of care pathways in the re-design of an emergency department is used forillustration. This study shows the role of pathway models as: a tool for re-design, a catalyst for enhancing communicationand as a repository for audit information. The final role of a tool for modelling contingencies was not implemented. Fromthe example it can be concluded that sophisticated models can be useful, in some applications; however, the simplerapproaches may often be the best, offering rapid, transparent recommendations based on a multidisciplinary approach

Erratum to: Seismic waves in 3-D: from mantle asymmetries to reliable seismic hazard assessment

Acknowledgments This paper is strongly relying upon the work of many colleagues and collaborators to whom we are greatly thankful, in particular: Carlo Doglioni, Gillian Foulger, Vahid Gholami, Hossein Hamzehloo, Volodya Kossobokov, Cristina La Mura, Anatoly Levshin, Andrea Magrin, Antonella Peresan, Federica Riguzzi, Franco Vaccari, Peter Varga, Tatiana Yanovskaya. Financial support from PRIN 2010-2011 and RITMARE projects, funded by Italian Ministry of University and Research, is gratefully acknowledged. In addition, Fig. 3 should be updated by new one as below

Treatment of synthetic textile wastewater containing dye mixtures with microcosms

The aim was to assess the ability of microcosms (laboratory-scale shallow ponds) as a post polishing stage for the remediation of artificial textile wastewater comprising two commercial dyes (basic red 46 (BR46) and reactive blue 198 (RB198)) as a mixture. The objectives were to evaluate the impact of Lemna minor L. (common duckweed) on the water quality outflows; the elimination of dye mixtures, organic matter, and nutrients; and the impact of synthetic textile wastewater comprising dye mixtures on the L. minor plant growth. Three mixtures were prepared providing a total dye concentration of 10 mg/l. Findings showed that the planted simulated ponds possess a significant (p < 0.05) potential for improving the outflow characteristics and eliminate dyes, ammonium-nitrogen (NH4-N), and nitrate-nitrogen (NO3-N) in all mixtures compared with the corresponding unplanted ponds. The removal of mixed dyes in planted ponds was mainly due to phyto-transformation and adsorption of BR46 with complete aromatic amine mineralisation. For ponds containing 2 mg/l of RB198 and 8 mg/l of BR46, removals were around 53%, which was significantly higher than those for other mixtures: 5 mg/l of RB198 and 5 mg/l of BR46 and 8 mg/l of RB198 and 2 mg/l of BR46 achieved only 41 and 26% removals, respectively. Dye mixtures stopped the growth of L. minor, and the presence of artificial wastewater reduced their development