217 research outputs found

    PHOTOELECTRIC CHARACTERIZATION OF P3HT POLYMER/PbS NANOCRYSTAL COMPOSITS

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    Photoelectric properties of new type conjugated polymer-semiconductor nanocrystals hybrid solar cells were investigated. Dependencies of charge carrier generation, mobility and recombination on composition of samples and the way how the samples were prepared were evaluated by using ultrafast time-resolved fluorescence, transient photocurrent and delayed collection field techniques. The combination of several investigation techniques enabled to distinguish and investigate three processes determining solar cell efficiency: charge carrier generation, carrier recombination and extraction. Charge carrier generation was found to be limited by relatively slow electron transfer from photoexcited polymer to PbS nanoparticles, but this process was determined being independent of the electric field strength. Carrier recombination and extraction rates strongly depend on the PbS nanoparticle concentration and determine the extraction efficiency. Efficient carrier extraction at short circuit conditions is possible only in chemically and thermally treated samples with high PbS nanoparticle concentration

    Influencia de un cosechado nocturno de aceitunas en “Salento” sobre la calidad del aceite de oliva virgen extra

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    In southern Italy, some olive cultivars such as ‘Ogliarola Salentina’ ripen when the day temperature is still high, at up to 28 to 30 °C. This can affect both the oil quality and the expression of its valuable characteristics. In addition, it increases the risk of undesirable fermentation that can generate off-flavors. In the present study, nocturnal olive harvesting was carried out to determine the influence that temperature can have on the characteristics of the extra virgin olive oil, and particularly on the volatile and oxidative compounds. The data obtained are encouraging: the lower temperatures that occur during the night appear to have a particular and positive impact on the organoleptic characteristics of the extra virgin olive oil produced, with enhanced formation of the volatile compounds that contribute to the ‘green’ notes of the flavor. In areas where daytime temperatures are very high, the nocturnal harvesting of olives at the correct stage of maturity therefore represents a good agronomic practice for the production of oils with high organoleptic and nutritional merit.En el sur de Italia, algunas variedades de olivo maduran cuando la temperatura del día sigue siendo alta, hasta 28 °C a 30 °C. Esto puede perjudicar la calidad del aceite y a la expresión de sus valiosas características, y aumenta el riesgo de fermentación indeseable que puede generar malos sabores. En el presente estudio, la cosecha nocturna de aceitunas se llevó a cabo para determinar la influencia que la temperatura puede tener sobre las características del aceite de oliva virgen extra, y en particular sobre los compuestos volátiles y los compuestos relacionados con la oxidación. Los datos obtenidos son alentadores: las temperaturas más bajas que se producen durante la noche parecen tener un impacto positivo en las características organolépticas del aceite de oliva virgen extra producido, con una mejora de la formación de los compuestos volátiles que contribuyen a las notas “verdes” del sabor. En las zonas donde las temperaturas diurnas son muy altas, la cosecha nocturna de aceitunas, representa, por tanto, una buena práctica agronómica para la producción de aceites con grandes ventajas organoléptica y nutritivas

    Climacteric Lowers Plasma Levels of Platelet-Derived Microparticles: A Pilot Study in Pre-versus Postmenopausal Women

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    Background: Climacteric increases the risk of thrombotic events by alteration of plasmatic coagulation. Up to now, less is known about changes in platelet-(PMP) and endothelial cell-derived microparticles (EMP). Methods: In this prospective study, plasma levels of microparticles (MP) were compared in 21 premenopausal and 19 postmenopausal women. Results: No altered numbers of total MP or EMP were measured within the study groups. However, the plasma values of CD61-exposing MP from platelets/megakaryocytes were higher in premenopausal women (5,364 x 10(6)/l, range 4,384-17,167) as compared to postmenopausal women (3,808 x 10(6)/l, range 2,009-8,850; p = 0.020). This differentiation was also significant for the subgroup of premenopausal women without hormonal contraceptives (5,364 x 10(6)/l, range 4,223-15,916; p = 0.047; n = 15). Furthermore, in premenopausal women, higher plasma levels of PMP exposing CD62P were also present as compared to postmenopausal women (288 x 10(6)/l, range 139-462, vs. 121 x 10(6)/l, range 74-284; p = 0.024). This difference was also true for CD63+ PMP levels (281 x 10(6)/l, range 182-551, vs. 137 x 10(6)/l, range 64-432; p = 0.015). Conclusion: Climacteric lowers the level of PMP but has no impact on the number of EMP in women. These data suggest that PMP and EMP do not play a significant role in enhancing the risk of thrombotic events in healthy, postmenopausal women. Copyright (C) 2012 S. Karger AG, Base

    APache Is an AP2-Interacting Protein Involved in Synaptic Vesicle Trafficking and Neuronal Development

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    Synaptic transmission is critically dependent on synaptic vesicle (SV) recycling. Although the precise mechanisms of SV retrieval are still debated, it is widely accepted that a fundamental role is played by clathrin-mediated endocytosis, a form of endocytosis that capitalizes on the clathrin/adaptor protein complex 2 (AP2) coat and several accessory factors. Here, we show that the previously uncharacterized protein KIAA1107, predicted by bioinformatics analysis to be involved in the SV cycle, is an AP2-interacting clathrin-endocytosis protein (APache). We found that APache is highly enriched in the CNS and is associated with clathrin-coated vesicles via interaction with AP2. APache-silenced neurons exhibit a severe impairment of maturation at early developmental stages, reduced SV density, enlarged endosome-like structures, and defects in synaptic transmission, consistent with an impaired clathrin/AP2-mediated SV recycling. Our data implicate APache as an actor in the complex regulation of SV trafficking, neuronal development, and synaptic plasticity

    PRRT2 controls neuronal excitability by negatively modulating Na+ channel 1.2/1.6 activity

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    Proline-rich transmembrane protein 2 (PRRT2) is the causative gene for a heterogeneous group of familial paroxysmal neurological disorders that include seizures with onset in the first year of life (benign familial infantile seizures), paroxysmal kinesigenic dyskinesia or a combination of both. Most of the PRRT2 mutations are loss-of-function leading to haploinsufficiency and 80% of the patients carry the same frameshift mutation (c.649dupC; p.Arg217Profs*8), which leads to a premature stop codon. To model the disease and dissect the physiological role of PRRT2, we studied the phenotype of neurons differentiated from induced pluripotent stem cells from previously described heterozygous and homozygous siblings carrying the c.649dupC mutation. Singlecell patch-clamp experiments on induced pluripotent stem cell-derived neurons from homozygous patients showed increased Na+ currents that were fully rescued by expression of wild-type PRRT2. Closely similar electrophysiological features were observed in primary neurons obtained from the recently characterized PRRT2 knockout mouse. This phenotype was associated with an increased length of the axon initial segment and with markedly augmented spontaneous and evoked firing and bursting activities evaluated, at the network level, by multi-electrode array electrophysiology. Using HEK-293 cells stably expressing Nav channel subtypes, we demonstrated that the expression of PRRT2 decreases the membrane exposure and Na+ current of Nav1.2/Nav1.6, but not Nav1.1, channels. Moreover, PRRT2 directly interacted with Nav1.2/Nav1.6 channels and induced a negative shift in the voltage-dependence of inactivation and a slow-down in the recovery from inactivation. In addition, by co-immunoprecipitation assays, we showed that the PRRT2-Nav interaction also occurs in brain tissue. The study demonstrates that the lack of PRRT2 leads to a hyperactivity of voltage-dependent Na+ channels in homozygous PRRT2 knockout human and mouse neurons and that, in addition to the reported synaptic functions, PRRT2 is an important negative modulator of Nav1.2 and Nav1.6 channels. Given the predominant paroxysmal character of PRRT2-linked diseases, the disturbance in cellular excitability by lack of negative modulation of Na+ channels appears as the key pathogenetic mechanism

    Sviluppo di strumenti tecnologici predittivi sanitario/meteo-ambientali per potenziare l’efficienza e la sostenibilità degli impianti di molluschicoltura: avvio del progetto FORESHELL

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    FORESHELL project is funded by the FLAG Costa Blu trough 2014-20 EMFF program of the Abruzzo Region. It is carrying out a pilot initiative to develop sanitary/weather-environmental predictive technological tools to enhance the efficiency and sustainability of the mussel farm in the Giulianova Maritime District. The hydrographic basins of the rivers close to the farm, Vibrata and Salinello, are constantly monitored trough the hydrological model (CHyM), to forecast occurrences of discharge peaks at the river mouth. Moreover, a specific sampling programme is established before and after severe weather events to determine the concentration of E. coli in freshwater at the river mouths and in mussels/seawater at the farming area. Until September 2021, there were 4 meteorological events that did not cause a peak discharge at the river mouth. Results did not show a significant increase of E. coli in the mussels. At the same time, the environmental parameters such as sea water temperature, salinity, chlorophyll a, sea currents and wave motion are acquired by the satellites and in situ probe. The web application for data visualisation is under construction, as well as the early warning signalling to the farmer. Furthermore, the growth of mussels is constantly monitored with biometric controls. In conclusion, the implementation of all phases of the FORESHELL project are progressing according to the timeline in order to develop innovative tools useful for the management of mussel farming area
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