Hidden secrets of the Northern Adriatic: "Tegnúe", peculiar reefs

Abstract Research carried out over the last 40 years has underlined the scientific importance of the rocky outcrops scattered on the Northern Adriatic Sea bed sometimes referred to as "tegnúe". The zoobenthic biocenoses developing over these peculiar geological formations are as extraordinary as they are unique. A study carried out for an entire year in two sampling stations, at different distances from the coast, revealed a very high number of zoobenthic species, including those which have now become rare and are therefore protected in Italian seas. The water turbidity of the northern Adriatic Sea greatly reduces the quantity of light reaching these outcrops, limiting the activity of autotrophic organisms only to sciaphilous genera. Thus, the most represented trophic categories of zoobenthos are suspension, especially filter feeders. Biodiversity values calculated for the communities of these particular reefs are far higher than normally found in the soft seabed in nearby areas, but even higher than in other coralligenous outcrops in other marine ecosystem in the world. The ecological role played by the tegnúe in the Northern Adriatic is extraordinary because as well as being true oases of biodiversity, they are areas naturally protected against bottom trawl-fishing. Thus, they offer shelter and reproduction sites for a number of fish and invertebrate species, including some under stress due to severe fishing pressure

Epitaxy and characterization of InP/InGaAs tandem solar cells grown by MOVPE on InP and Si substrates

The integration of III-V multi-junction solar cells on Si substrates is currently one of the most promising possibilities to combine high photovoltaic performance with a reduction of the manufacturing costs. In this work, we propose a prospective study for the realization of an InP/InGaAs tandem solar cell lattice-matched to InP on a commercially available Si template by direct MOVPE growth. The InP top cell and the InGaAs bottom cell were firstly separately grown and optimized using InP substrates, which exhibited conversion efficiencies of 13.5% and 11.4%, respectively. The two devices were then combined in a tandem device by introducing an intermediate InP/AlInAs lattice-matched tunnel junction, showing an efficiency of 18.4%. As an intermediate step towards the realization of the tandem device on Si, the InP and InGaAs single junction solar cells were grown on top of a commercial InP/GaP/Si template. This transitional stage enabled to isolate and evaluate the effects of the growth of III-V on Si on the photovoltaic performance through the comparison with the aforementioned devices on InP. Each cell was electrically characterized by external quantum efficiency and dark and illuminated current-voltage under solar simulator. The material quality was also analyzed by means of X-ray diffraction, Atomic-Force Microscopy, Transmission Electron and Scanning Electron Microscopy. The III-V on Si devices showed efficiencies of 3.6% and 2.0% for the InP and InGaAs solar cells, respectively

Serum Albumin Is Inversely Associated With Portal Vein Thrombosis in Cirrhosis

We analyzed whether serum albumin is independently associated with portal vein thrombosis (PVT) in liver cirrhosis (LC) and if a biologic plausibility exists. This study was divided into three parts. In part 1 (retrospective analysis), 753 consecutive patients with LC with ultrasound-detected PVT were retrospectively analyzed. In part 2, 112 patients with LC and 56 matched controls were entered in the cross-sectional study. In part 3, 5 patients with cirrhosis were entered in the in vivo study and 4 healthy subjects (HSs) were entered in the in vitro study to explore if albumin may affect platelet activation by modulating oxidative stress. In the 753 patients with LC, the prevalence of PVT was 16.7%; logistic analysis showed that only age (odds ratio [OR], 1.024; P = 0.012) and serum albumin (OR, -0.422; P = 0.0001) significantly predicted patients with PVT. Analyzing the 112 patients with LC and controls, soluble clusters of differentiation (CD)40-ligand (P = 0.0238), soluble Nox2-derived peptide (sNox2-dp; P < 0.0001), and urinary excretion of isoprostanes (P = 0.0078) were higher in patients with LC. In LC, albumin was correlated with sCD4OL (Spearman's rank correlation coefficient [r(s)], -0.33; P < 0.001), sNox2-dp (r(s), -0.57; P < 0.0001), and urinary excretion of isoprostanes (r(s), -0.48; P < 0.0001) levels. The in vivo study showed a progressive decrease in platelet aggregation, sNox2-dp, and urinary 8-iso prostaglandin F2 alpha-III formation 2 hours and 3 days after albumin infusion. Finally, platelet aggregation, sNox2-dp, and isoprostane formation significantly decreased in platelets from HSs incubated with scalar concentrations of albumin. Conclusion: Low serum albumin in LC is associated with PVT, suggesting that albumin could be a modulator of the hemostatic system through interference with mechanisms regulating platelet activation

Cellules solaires tandem à base de InP intégrées sur substrats Si par hétéro-épitaxie MOVPE

This thesis focuses on III-V/Si integration of single- and dual-junction solar cells by Metalorganic Vapor Phase Epitaxy (MOVPE). The photovoltaic devices were made with materials lattice matched to InP. The goal was to firstly obtain efficient devices on InP substrates and then to integrate them on a structure with a different lattice parameter, by evaluating the effects on the photovoltaic performances. This required the realization and the optimization of several manufacturing steps.Firstly, we realized an InP single junction device, which may correspond to the top cell of our tandem structure. This was also necessary to set up a manufacturing process for all the next cells. The growth conditions were optimized by taking advantage of material characterization techniques such as XRD, C-V profiling and SIMS. By optimizing thicknesses and doping levels of the various layers of the device, as well as the clean room process, we obtained a conversion efficiency of 12.9%, with a FF of 84.3%. We demonstrated that the use of an AlInAs window layer instead of InP may increase the efficiency to 13.5%, despite a slight reduction in FF (81.4%). The same procedure was then extended to the realization of an InGaAs solar cell as the bottom component of the tandem device. We obtained an efficiency of 11.4% and a FF of 74.5%.In parallel, tunnel junctions able to electrically connect the two subcells in a tandem device were studied. In particular, we focused our attention on the growth conditions of the junction anode, which was made in AlInAs and doped with CBr4 precursor. The particular chemical interactions that such a precursor has with Al precursor and In required a relevant reduction of growth temperature to 540 °C. By determining the effects of the flows on composition and doping levels of the compound, we obtained a high doping of +4x1019 cm-3. By obtaining an equivalent level for the InP:S cathode, we realized a device presenting a Jp of 1570 A/cm2, able to work under high solar concentration conditions. By finally combining the three presented devices in a tandem cell, we could obtain an overall conversion efficiency of 18.3%, with a FF of 83.9%.A proper template for III-V/Si integration was determined by testing several possibilities provided by different partners. XRD and AFM characterizations demonstrated that an InP/GaP/Si template provided by NAsP Company was the best option. This was confirmed by the growth of an InP single junction cell over the template. The processing over a Si substrate was made possible by shifting the rear contact of the cell on the front side of the device, which required the development of a proper set of photolithographic masks. The successful integration of the III-V solar cells on Si was confirmed by the relevant produced photocurrent. This corresponds to around 60% of the value obtained on InP substrates. Furthermore, the measured J-V characteristics show a diode-like trend, which demonstrates the validity of the proposed approach.Cette thèse s’intéresse à l'intégration sur Si de cellules solaires III-V à simple et double jonction par épitaxie en phase vapeur aux organo-métalliques (MOVPE). Les dispositifs photovoltaïques ont été réalisés avec des matériaux accordés sur InP. L'objectif était d'abord d'obtenir des dispositifs performants sur des substrats InP, puis de les intégrer sur une structure avec un paramètre de maille différent, en évaluant les effets sur les performances photovoltaïques. Ceci a nécessité la réalisation et l'optimisation de plusieurs étapes de fabrication.Tout d'abord, nous avons réalisé une cellule InP à simple jonction, qui peut correspondre à la cellule top dans notre structure tandem. Cela était également nécessaire pour mettre en place un processus de fabrication pour toutes les cellules suivantes. Les conditions de croissance ont été optimisées en profitant des techniques de caractérisation des matériaux telles que la XRD, l’analyse C-V et le SIMS. En optimisant les épaisseurs et les niveaux de dopage des différentes couches du dispositif, ainsi que le procédé en salle blanche, nous avons obtenu une efficacité de conversion de 12.9%, avec un FF de 84.3%. Nous avons démontré que l'utilisation d'une couche fenêtre en AlInAs au lieu de l’InP peut augmenter l'efficacité à 13.5%, malgré une légère réduction du FF (81.4%). La même procédure a ensuite été étendue à la réalisation d'une cellule solaire InGaAs comme cellule bottom du dispositif tandem. Nous avons obtenu un rendement de 11.4% et un FF de 74.5%.En parallèle, des jonctions tunnels capables de relier électriquement les deux sous-cellules dans un dispositif tandem ont été étudiées. En particulier, nous avons concentré notre attention sur les conditions de croissance de l'anode de la jonction, qui a été fabriquée en AlInAs et dopée avec le précurseur CBr4. Les réactions chimiques d’un tel précurseur avec le précurseur de l’Al et l’In nécessitaient une importante réduction de la température de croissance à 540 °C. En déterminant les effets des flux sur la composition et les niveaux de dopage du composé, nous avons obtenu un dopage élevé de +4x1019 cm-3. En obtenant un niveau équivalent pour la cathode InP:S, nous avons réalisé un dispositif présentant un Jp de 1570 A/cm2, capable de fonctionner dans des conditions de concentration solaire élevée. En combinant finalement les trois dispositifs présentés dans une cellule tandem, nous avons pu obtenir un rendement global de conversion de 18.3%, avec un FF de 83.9%.Un template approprié pour l'intégration III-V/Si a été déterminé en testant plusieurs possibilités fournies par différents partenaires. Les caractérisations XRD et AFM ont démontré qu'un template InP/GaP/Si fourni par la société NAsP était la meilleure option. Ceci a été confirmé par la croissance d'une cellule InP à simple jonction sur le template. La techno sur un substrat Si a été rendu possible en déplaçant le contact arrière de la cellule sur la face avant du dispositif, ce qui a nécessité la mise au point d'un ensemble approprié de masques photolithographiques. La réussite de l’intégration des cellules solaires III-V sur Si a été confirmée par le photocourant produit. Celui-ci correspond à environ 60% de la valeur obtenue sur les substrats InP. De plus, les caractéristiques J-V mesurées donnent une tendance de type diode, démontrant la validité de l'approche proposée

InP:S/AlInAs:C Tunnel Junction Grown by MOVPE for Photovoltaic Applications

International audienceMultijunction solar cells based on III–V compounds are one of the most effective possibilities to achieve high efficiencies for space and terrestrial applications. In this work, AlInAs:C/InP:S tunnel junctions are fabricated using MOVPE. Type‐II interface band alignment of AlInAs/InP heterostructure is ideal for increasing the photogenerated carriers tunneling. Furthermore, wide bandgaps ensure a high transmission of the incident light. The J–V characteristics of the final devices show very good results in terms of tunneling peak current density (1000 A cm−2) and specific resistance at low applied bias, making them compatible for photovoltaic applications

The clinical impact of an extra virgin olive oil enriched mediterranean diet on metabolic syndrome: Lights and shadows of a nutraceutical approach

For years it has been established that the only truly effective treatment of metabolic syndrome (MS) is lifestyle modification to prevent its cardiovascular (e.g., coronary artery disease and atherosclerosis), metabolic (e.g., diabetes mellitus), and hepatic (e.g., steatosis and non-alcoholic steatohepatitis) complications. The focal points of this approach are to increase physical activity and intake of a diet characterized by high quantities of fruits, vegetables, grains, fish, and low-fat dairy products, the so called mediterranean diet (MD); however, the added value of MD is the presence of extra virgin olive oil (EVOO), a healthy food with a high content of monounsaturated fatty acids, especially oleic acid, and variable concentrations (range 50-800 mg/kg) of phenols (oleuropein, ligstroside, and oleocanthal, and their derivatives, phenolic alcohols, such as hydroxytyrosol and tyrosol). Phenolic compounds not only determine EVOO's main organoleptic qualities (oxidative stability, specific flavor, and taste features) but, theoretically, make it a source of antioxidant, anti-inflammatory, insulin-sensitizing, cardioprotective, antiatherogenic, neuroprotective, immunomodulatory, and anticancer activity. Although many studies have been carried out on EVOO's clinical effects and attention toward this dietary approach (healthy and palatable food with strong nutraceutical activity) has become increasingly pressing, there are still many dark sides to be clarified, both in terms of actual clinical efficacy and biochemical and molecular activity. Thus, we reviewed the international literature, trying to show the state of the art about EVOO's clinical properties to treat MS (along with correlated complications) and the future prospective of its nutraceutical use

Contact Dermatitis Due to Nickel Allergy in Patients Suffering from Non‐Celiac Wheat Sensitivity

BACKGROUND: Non‐celiac wheat sensitivity (NCWS) is a new clinical entity in the world of gluten‐related diseases. Nickel, the most frequent cause of contact allergy, can be found in wheat and results in systemic nickel allergy syndrome and mimics irritable bowel syndrome (IBS). OBJECTIVE: To evaluate the frequency of contact dermatitis due to nickel allergy in NCWS patients diagnosed by a double‐blind placebo‐controlled(DBPC)challenge,and to identify the characteristics of NCWS patients with nickel allergy. METHODS: We performed a prospective study of 60 patients (54 females, 6 males; mean age 34.1 ± 8.1 years) diagnosed with NCWS from December 2014 to November 2016; 80 age‐ and sex‐matched subjects with functional gastrointestina l symptoms served as controls. Patients reporting contact dermatitis related to nickel‐containing objects underwent nickel patch test (Clinicaltrials.gov registration number: NCT02750735). RESULTS: Six out of sixty patients (10%) with NCWS suffered from contact dermatitis and nickel allergy and this frequency was statistically higher (p = 0.04)than observed in the control group(5%. The main clinical characteristic of NCWS patients with nickel allergy was a higher frequency of cutaneous symptoms after wheat ingestion compared to NCWS patients who did not suffer from nickel allergy (p < 0.0001. CONCLUSIONS: Contact dermatitis and nickel allergy are more frequent in NCWS patients than in subjects with functional gastrointestinal disorders;furthermore, these patients had a very high frequency of cutaneous manifestations after wheat ingestion. Nickel allergy should be evaluated in NCWS patients who have cutaneous manifestations after wheat ingestion

Epitaxy and characterization of InP/InGaAs tandem solar cells grown by MOVPE on InP and Si substrates

The integration of III-V multi-junction solar cells on Si substrates is currently one of the most promising possibilities to combine high photovoltaic performance with a reduction of the manufacturing costs. In this work, we propose a prospective study for the realization of an InP/InGaAs tandem solar cell lattice-matched to InP on a commercially available Si template by direct MOVPE growth. The InP top cell and the InGaAs bottom cell were firstly separately grown and optimized using InP substrates, which exhibited conversion efficiencies of 13.5% and 11.4%, respectively. The two devices were then combined in a tandem device by introducing an intermediate InP/AlInAs lattice-matched tunnel junction, showing an efficiency of 18.4%. As an intermediate step towards the realization of the tandem device on Si, the InP and InGaAs single junction solar cells were grown on top of a commercial InP/GaP/Si template. This transitional stage enabled to isolate and evaluate the effects of the growth of III-V on Si on the photovoltaic performance through the comparison with the aforementioned devices on InP. Each cell was electrically characterized by external quantum efficiency and dark and illuminated current-voltage under solar simulator. The material quality was also analyzed by means of X-ray diffraction, Atomic-Force Microscopy, Transmission Electron and Scanning Electron Microscopy. The III-V on Si devices showed efficiencies of 3.6% and 2.0% for the InP and InGaAs solar cells, respectively

Epitaxy and characterization of InP/InGaAs tandem solar cells grown by MOVPE on InP and Si substrates

International audienceThe integration of III-V multi-junction solar cells on Si substrates is currently one of the most promising possibilities to combine high photovoltaic performance with a reduction of the manufacturing costs. In this work, we propose a prospective study for the realization of an InP/InGaAs tandem solar cell lattice-matched to InP on a commercially available Si template by direct MOVPE growth. The InP top cell and the InGaAs bottom cell were firstly separately grown and optimized using InP substrates, which exhibited conversion efficiencies of 13.5% and 11.4%, respectively. The two devices were then combined in a tandem device by introducing an intermediate InP/AlInAs lattice-matched tunnel junction, showing an efficiency of 18.4%. As an intermediate step towards the realization of the tandem device on Si, the InP and InGaAs single junction solar cells were grown on top of a commercial InP/GaP/Si template. This transitional stage enabled to isolate and evaluate the effects of the growth of III-V on Si on the photovoltaic performance through the comparison with the aforementioned devices on InP. Each cell was electrically characterized by external quantum efficiency and dark and illuminated current-voltage under solar simulator. The material quality was also analyzed by means of X-ray diffraction, Atomic-Force Microscopy, Transmission Electron and Scanning Electron Microscopy. The III-V on Si devices showed efficiencies of 3.6% and 2.0% for the InP and InGaAs solar cells, respectively