372 research outputs found

    Perception of climate change, loss of social capital and mental health in two groups of migrants from African countries

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    AbstractIntroduction. The negative effects of climate change affect community subsistencemodels, thus determining an increase in social conflicts, a loosening of social capital, anincrease in the incidence of traumas and diseases, and a push for migration.Aim. This exploratory research compares the perception of climate change, as well as thereduction of social capital and mental health, in two groups of migrants arriving in Italyfrom African countries with high or extreme vulnerability to climate change.Methods. The perception of climate change and the degree of social capital were assessedwith a semi-structured interview. The psychological condition was investigatedthrough a clinical psychological interview and tests.Results. The group of migrants coming from countries with extreme exposure to climatechange perceive greater vulnerability of their country and reports a greater loss of socialcapital. The level of education does not seem to affect the ability to perceive climatechange. In the entire sample, there is a strong correlation between the perception ofchange and the loss of social capital, and between the loss of social capital and emotionaldisorders.Conclusions. The study suggests that actions to preserve the social capital of a communitystrongly exposed to climate change can mitigate the impact of change on mentalhealth

    Interaction and coherence of a plasmon-exciton polariton condensate

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    Polaritons are quasiparticles arising from the strong coupling of electromagnetic waves in cavities and dipolar oscillations in a material medium. In this framework, localized surface plasmon in metallic nanoparticles defining optical nanocavities have attracted increasing interests in the last decade. This interest results from their sub-diffraction mode volume, which offers access to extremely high photonic densities by exploiting strong scattering cross-sections. However, high absorption losses in metals have hindered the observation of collective coherent phenomena, such as condensation. In this work we demonstrate the formation of a non-equilibrium room temperature plasmon-exciton-polariton condensate with a long range spatial coherence, extending a hundred of microns, well over the excitation area, by coupling Frenkel excitons in organic molecules to a multipolar mode in a lattice of plasmonic nanoparticles. Time-resolved experiments evidence the picosecond dynamics of the condensate and a sizeable blueshift, thus measuring for the first time the effect of polariton interactions in plasmonic cavities. Our results pave the way to the observation of room temperature superfluidity and novel nonlinear phenomena in plasmonic systems, challenging the common belief that absorption losses in metals prevent the realization of macroscopic quantum states.Comment: 23 pages, 5 figures, SI 7 pages, 5 figure

    Is There Daily Growth Hysteresis versus Vapor Pressure Deficit in Cherry Fruit?

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    The growth of cherry fruit is generally described using a double sigmoid model, divided into four growth stages. Abiotic factors are considered to be significant components in modifying fruit growth, and among these, the vapor pressure deficit (VPD) is deemed the most effective. In this study, we investigated sweet cherry fruit growth through the continuous, hourly monitoring of fruit transversal diameter over two consecutive years (2019 and 2020), from the beginning of the third stage to maturation (forth stage). Extensometers were used in the field and VPD was calculated from weather data. The fruit growth pattern up to the end of the third stage demonstrated three critical steps during non-rainy days: shrinkage, stabilization and expansion. In the third stage of fruit growth, a partial clockwise hysteresis curve of circadian growth, as a response to VPD, appeared on random days. The pattern of fruit growth during rainy days was not distinctive, but the amount and duration of rain caused a consequent decrease in the VPD and indirectly boosted fruit growth. At the beginning of the fourth stage, the circadian growth changed and the daily transversal diameter vs VPD formed fully clockwise hysteresis curves for most of this stage. Our findings indicate that hysteresis can be employed to evaluate the initial phenological phase of fruit maturation, as a fully clockwise hysteresis curve was observable only in the fourth stage of fruit growth. There are additional opportunities for its use in the management of fruit production, such as in precision fruit farming

    Determination of band-offset enhanced in InGaAsP -InGaAsP strained multiquantum wells by photocurrent measurements

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    We experimentally determine the band offset of strain-compensated InGaAsP-InGaAsP multiquantum-well (MQW) heterostructures, emitting at 1.55 mum, that were grown by metal-organic chemical vapor deposition. A band offset value of about 56% is found for the conduction band, which is higher than the value reported for the unstrained structure. The temperature dependence of the photoluminescence intensity shows that the unipolar detrapping of carriers in such MQWs is more efficient than the thermal activation of excitons. (C) 2005 American Institute of Physic

    An Alternative Tool for Intra-Row Weed Control in a High-Density Olive Orchard

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    none6openAssirelli, Alberto; Ciaccia, Corrado; Giorgi, Veronica; Zucchini, Matteo; Neri, Davide; Lodolini, Enrico MariaAssirelli, Alberto; Ciaccia, Corrado; Giorgi, Veronica; Zucchini, Matteo; Neri, Davide; Lodolini, Enrico Mari

    Radiative recombination dynamics in tetrapod-shaped CdTe nanocrystals: Evidence for a photoinduced screening of the internal electric field

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    We study the radiative recombination processes in CdTe tetrapod nanocrystals at 10K. Two intrinsic emission bands, namely the ground state (GS) and the excited state (EX), decay with three time constants, due to a power dependent Auger-like recombination process (tens of picoseconds), to the intrinsic emission of the two states (hundreds of picoseconds) and to emission from defect states (a few nanoseconds). The existence of an internal electric field originating from the e-h separation induced by the peculiar symmetry of the GS is demonstrated by a dynamical shift of the GS emission energy that is correlated to the EX population

    How harvest, cleaning and conservation good practices affect the quality of saffron: results of a research conducted in Italy

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    Saffron (Crocus sativus L.) spice making requires time-spending manual operations: stigmas are separated from the flower picked in bud early in the morning, and once dried they are preserved protected from light. This study verified how the correct pursuing of these good practices affects saffron quality. Few hours of exposure of the flower to the sun determined a significant decrease in the colouring strength (239.66 ± 10.33 versus 255.35 ± 11.87). The correct cleaning of stigmas determined a very significant increase of colouring strength (247.12 ± 13.32 instead of 224.35 ± 14.88) and a significant increase of flavour strength (99.72 ±7.48 against 90.31 ± 6.32, p <0.05). In 24 months, all the samples kept in the dark were still of first category of quality while the ones kept in the light dropped in second category. For all samples there was an increase of aroma strength and a decrease of the flavour and colouring strength, but only the colouring strength loss followed a significantly more sloping trendline. A detectable difference in the content of trans-crocin 4 correlated to the ageing or the way of conservation was not found, nevertheless, it was confirmed that the isomers tend towards a photostationary state where the trans isomer is more present
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