Ecology of the toxic dinoflagellate Ostreopsis cf. ovata along the coasts of the Campania region (Tyrrhenian Sea, Mediterranean Sea)

Blooms of the toxic dinoflagellate Ostreopsis genus are a recurrent phenomenon in tropical and temperate regions worldwide. The most widely distributed species in the Mediterranean Sea, Ostreopsis cf. ovata, produces blooms with increasing intensity, frequency and distribution. These blooms have been associated with respiratory problems and skin irritations in humans, causing health problems along Italian coasts. In addition, palytoxin-like substances produced by this species can be accumulated by various organisms and make the seafood toxic, with further risks to human health. This thesis is based on the analysis of a multiannual dataset gathered at different coastal sites along the Campania region: 1) the area of Posillipo, in the Gulf of Naples, where the most intense blooms of O. cf. ovata for the Campania Region are regularly recorded; 2) the Ischia Island coasts, which are subjected to natural acidification due to the presence of volcanic vents; 3) the sandy littoral of the Gulf of Salerno littoral, where O. cf. ovata has not been found previously, and where structures for the defence from coastal erosion will be built. Results showed that: i) Ostreopsis cf. ovata blooms are a stable phenomenon, occurring at regular frequency over the years in summer months along Posillipo and Ischia Island coasts; ii) the blooms show a marked seasonality, with peaks in the summer months, thus representing a risk for people during the bathing season, either through direct contact and aerosol or following the consumption of contaminated seafood; iii) based on the results from the Ischia island, a lower pH does not affect Ostreopsis blooms, meaning no risk decrease in future scenarios of ocean acidification; iv) Ostreopsis does occur in the Gulf of Salerno, although at low concentrations, probably due to the absence of a suitable substrate; by providing a hard substrate for macroalgae hosting Ostreopsis blooms, artificial structures against coastal erosion might determine an increase of the species in an area where it has not represented a risk so far. The present study highlights the relevance of appropriate strategies for monitoring Ostreopsis blooms. Knowledge and data obtained can be used for a better assessment and interpretation of these phenomena, thus supporting informed management actions to protect the environment, seafood resources and human health

Qualité réglée, qualité gérée

Ce texte est un chapitre destiné à publication dans un ouvrage collectif du CRTD sur "Qualité du travail, qualité au travail"La recherche de la qualité a envahi les politiques de management, dans des contextes variés : secteur industriel, secteur des services, service public. La qualité est supposée être obtenue par la définition et l'application de standards, de procédures, de référentiels, de règles, de normes. On parlera alors de "qualité réglée". La "qualité gérée" repose à l'inverse sur les capacités d'initiative des opérateurs, seuls ou en groupe, à faire face à l'imprévisible et à la variabilité naturelle du réel. A partir de quelques exemples, on montre que la qualité du travail est la résultante d'ajustements, de compromis, d'optimisations entre critères de sécurité, de performance et d'équité. La qualité gérée n'est pas seulement le comblement des lacunes de la qualité réglée ou la réponse à des violations à la qualité réglée. C'est aussi un jugement sur la pertinence, dans des circonstances données, de l'application de la qualité réglée et la conception et la mise en œuvre d'un arbitrage raisonné permettant l'atteinte du meilleur niveau de qualité possible dans le contexte particulier

Thermal characterization of electrically injected thin-film InGaAsP microdisk lasers on Si

Abstract—We have performed a numerical and experimental analysis of the thermal behavior of electrically injected microdisk lasers that are defined in an InGaAsP-based thin film bonded on top of a silicon wafer. Both the turn-on as well as the pulsed-regime temperature evolution in the lasing region was simulated using the finite-element method. The simulation results are in good agreement with experimental data, which was extracted from the broadening of the time-averaged emission spectra. Lasing at room temperature was only possible in pulsed regime due to the high thermal resistance (10 K/mW). Some strategies to decrease the thermal resistance of the microdisk lasers are proposed and discussed. Index Terms—Heterogeneous integration, InGaAsP, integrated optics, microdisk laser, Si, thermal characterization

Immunosuppression and Viral Infections

Immunosuppression is commonly used for prevention of graft rejection in solid organ transplantation (SOT) and prevention of graft versus host disease in hematopoietic allogeneic stem cell transplant (ASCT). In ASCT, immunosuppression is used to control GVHD and can be tapered off within 6–12 months after transplantation. SOT recipients require lifelong immunosuppression to prevent graft rejection, making them susceptible to serious viral infections including EBV PTLD. EBV PTLD occurs within the first 6 months following ASCT prior to effective reconstitution of cytotoxic T lymphocytes (CTL). Our understanding on EBV-related PTLD is mostly extrapolated from SOT-associated PTLD. Features of conditioning and use of serotherapy remain important in development of EBV PTLD. Other viral infections that occur early post-transplant include CMV, HHV6, BK, and adenovirus, and usually correspond to degree of immunosuppression post-transplant. These infections are associated with significant morbidity and mortality. However, the current literature lacks information on outcomes of viral infections related to immunosuppression. Alternative donor ASCT are now more common, and patients are more susceptible to multiple viral infectious complications at the peak of immunosuppression and require monitoring for viral infections in these immunosuppressed patients

Self-alignment of silicon chips on wafers: a capillary approach

As the limits of Moores law are approached, three-dimensional integration appears as the key to advanced microelectronic systems. Die-to-wafer assembly appears to be an unavoidable step to reach full integration. While robotic methods experience difficulties to accommodate fabrication speed and alignment accuracy, self-assembly methods are promising due to their parallel aspect, which overcomes the main difficulties of current techniques. The aim of this work is the understanding of the mechanisms of self-alignment with an evaporating droplet technique. Stable and unstable modes are examined. Causes for misalignments of chips on wafers and their evolution are investigated with the help of the SURFACE EVOLVER numerical software. Precautions for suitable alignment are proposed

Silicon Die Self-alignment on a Wafer: Stable and Unstable Modes

3D integration is the key to advanced microelectronic systems. Die-to-wafer assembly is a necessary step to reach full integration. Self-assembly methods are promising due to their parallel aspect which overcomes the main difficulties of the current techniques. The aim of this work is the understanding of the mechanisms of self-alignment with an evaporating droplet technique and the investigation the stable and unstable modes. Using the Surface Evolver software, we analyze the causes for misalignments of the system and their evolution

Análise numérica da influência de pás auxiliares no desempenho aerodinâmico e acústico de ventiladores centrífugos

This work presents a Methodology for Numerical Analysis of Centrifugal Fans with splitter blades through Computational Fluid Dynamics Techniques (CFD), to determine the influence of splitter blades on fan behavior and broadband noise sources. It was considered a rotor with ten main blades in a circle arc shape. A three-dimensional numerical simulations of the complete steady flow field in the whole impeller were considered, the inlet velocity and constant speed rotation as boundary conditions were given based on the experimental test. The numerical results of the rotor without splitter blades was conducted by comparison with the experimental data from the UNIFEI fan test rig. The turbulence model employed k-w SST was suitable to identify viscous effects and energy dissipation by turbulent viscosity provides a good qualitative prediction with the experimental results. Regarding the acoustic power levels results, based on the sound pressure, it was satisfactory based on analysis in the literature. Aerodynamic loading analysis were also performed to quantify the effects on efficiency considering the splitter blades.Este trabalho apresenta uma análise numérica de ventiladores centrífugos com pás auxiliares através de técnicas de Dinâmica dos Fluidos Computacional (CFD), para determinar a influência das pás auxiliares no comportamento aerodinâmico do ventilador e as fontes de ruído de banda larga. Foi considerado um rotor com 10 pás principais em formato de arco de círculo com 10 pás auxiliares intercaladas às pás principais. Para as análises do campo de escoamento foram consideradas simulações em regime permanente, onde as condições de contorno de velocidade na entrada, mantendo a rotação constante foram dadas com base no ensaio experimental. Em princípio, os resultados numéricos do rotor sem pás auxiliares foram validados com dados experimentais obtidos do banco de ensaios de ventiladores da UNIFEI. O modelo de turbulência empregado k-w SST, mostrou-se adequado na identificação dos efeitos viscosos e a dissipação de energia pela viscosidade turbulenta, resultando numa representação numérica coerente com os dados experimentais. Em relação à potência acústica, com base na pressão sonora, os resultados foram satisfatórios, com base em análises disponíveis na literatura. Foram também feitas análises de carregamentos aerodinâmicos para quantificar os efeitos no rendimento hidráulico considerando as pás auxiliares

Indium phosphide based membrane photodetector for optical interconnects on silicon

We have designed, fabricated and characterized an InP-based membrane photodetector on an SOI wafer containing a Si-wiring photonic circuit. New results on RF characterization up to 20 GHz are presented. The detector fabrication is compatible with wafer scale processing steps, guaranteeing compatibility towards future generation electronic IC processing

The dark side of springs: what drives small-scale spatial patterns of subsurface meiofaunal assemblages?

International audience; Springs are amongst the most relevant Groundwater Dependent Ecosystems (GDEs) and are key research environments in freshwater ecology and biology. The strict dependency on ground water of surface spring biodiversity is widely recognized, whereas the biodiversity occurring below the spring is very poorly known. This study analyzes copepod assemblages in the subsurface habitat of a karstic rheo- limnocrenic spring in relation to seventeen environmental parameters. Subsurface copepod assemblages were sensitive to microspatial variation in habitat structure, and species distributions were mostly driven by groundwater flowpath and substratum type, resulting in biologically distinct limnocrenic and rheocrenic sectors at the spring system scale. Habitat patchiness was reflected in differences in the microdistribution of subsurface copepods, stygobiotic assemblages being more sensitive to the measured environmental gradients than non-stygobiotic ones. In spite of the apparent stability of spring environments, copepods, as a target group, performed well as de- scriptors of sediment texture and hydrodynamics, and may offer relevant information for a better understanding of the potential changes generated by anthropogenic disturbance on these ecosystems