Guide sur les techniques de restauration du sol en viticulture

Guidelines for soil functionality restoration in degraded areas of vineyard (French language

Guía de técnicas de restauración de suelos degradados en viticultura

Guidelines for soil functionality restoration in degraded areas of vineyard (spanish language

IMPACT OF AGRICULTURAL MANAGEMENT ON COMMUNITIES OF ORIBATIDA, GAMASINA AND COLLEMBOLA IN ITALIAN AND FRENCH VINEYARDS

Quantitative and qualitative analyses among the soil microarthropods can be used in biomonitoring as tools in multi-disciplinary approach to characterize soil quality. Three groups of microarthropods - Collembola and Oribatida as detrivores and Gamasina as predators - were selected to evaluate the impact of different management treatments adopted to recover degraded soil in organic. Differences in arthropod populations between French and Italian sites were registered. In Italy, after two years of recovering treatments, an increase of the abundances of all groups, particularly detritivores in degraded plots, was observed. The population of gamasids increased, in all sites, only in non degraded plots. Soil invertebrates of similar trophic groups, like collembolans and oribatids, seem to differently respond to treatments: the collembolans were more affected by some agronomic practices enhancing soil fertility

Effect of organic treatments on soil carbon and nitrogen dynamics in vineyard

The work aims to investigate the effects of different soil management strategies on carbon sequestration and total nitrogen in areas of vineyards suffering from loss of soil functionality. Treatments, selected for inter-row management, to re-install soil functionality were based on compost or other organic amendments (COMP), green manure (GM), and dry mulching (DM) strategies using winter legumes and cereals. Cover crops were seeded in fall and mown in late spring, leaved in the ground for mulching in DM or incorporated into the uppermost soil layers in GM. Such approaches were investigated in six vineyards in Italy, six in France, and two vineyards in Slovenia and Turkey. The results showed that COMP significantly increased total organic carbon (TOC) and total nitrogen (Ntot) in the topsoil after one year of application. Also DM tends to increase significantly TOC in the topsoil, but only after two years. Modelling 20-year carbon stock dynamics in Italy vineyards, the average increase resulted 0.49, 0.34, 0.21 and 0.03 Mg C ha-1 yr-1 for COMP, DM, GM and control, respectively

Effects of Lattice and Molecular Phonons on Photoinduced Neutral-to-Ionic Transition Dynamics in Tetrathiafulvalene-pp-Chloranil

For electronic states and photoinduced charge dynamics near the neutral-ionic transition in the mixed-stack charge-transfer complex tetrathiafulvalene-$p$-chloranil (TTF-CA), we review the effects of Peierls coupling to lattice phonons modulating transfer integrals and Holstein couplings to molecular vibrations modulating site energies. The former stabilizes the ionic phase and reduces discontinuities in the phase transition, while the latter stabilizes the neutral phase and enhances the discontinuities. To reproduce the experimentally observed ionicity, optical conductivity and photoinduced charge dynamics, both couplings are quantitatively important. In particular, strong Holstein couplings to form the highly-stabilized neutral phase are necessary for the ionic phase to be a Mott insulator with large ionicity. A comparison with the observed photoinduced charge dynamics indicates the presence of strings of lattice dimerization in the neutral phase above the transition temperature.Comment: 9 pages, 7 figures, accepted for publication in J. Phys. Soc. Jp

Soil functionality assessment in degraded plots of vineyards

Land transformation to adapt fields to mechanization in perennial crop farming is a common practice which includes land levelling, deep ploughing, stone-breakage and clearing, application of fertilizers and amendments. Manipulation of the natural soil profile along its entire depth can severely disturb the naturally existing chemical physical,biological and hydrological equilibrium (Costantini and Barbetti, 2008; Costantini et al., 2013). The most common effects of the land transformation are mixing of soil horizons and soil truncation, which result in reduction of soil depth and available water, organic matter depletion, enrichment of calcium carbonate content in the topsoil,imbalance of some element ratio, and decline in the activity and diversity of soil biological communities involved in nutrient cycles. A decline in the capacity of soil to accommodate the soil-dwelling organisms causes a strong impact on several ecosystem services, in particular, the growth of the vine, the quality and quantity of the grapes,the production costs and the risk of erosion. These negative effects of a pre-planting mismanagement can occur simultaneously and interact to decrease soil fertility and grapevine performance (Lanyon et al., 2004; Tagliavini and Rombolà, 2001; Martínez-Casasnovas and Ramos, 2009).Since soil spatial variability is usually high, soil manipulations frequently result into reduced soil functionality and decline of soil ecosystem services in defined plots of the vineyards. Sometimes soil degradation in these areas is very high and compromises not only vine performance and crop yield, but also disease resistance of plants to diseases and their survival. The impact of improper soil manipulations in vineyards may be of particular concern, because vineyards are frequently located on marginal hillsides, which are sensitive to soil erosion and characterized by shallow soil depth (Ramos, 2006). This paper wants to show the assessment of soil functionality in degraded areas within two farms in Tuscany. This work reports the results of the first activities in Italian sites of the ReSolVe Core-organic+ project, aimed at restoring optimal Soil functionality in degraded areas within organic European vineyards

Structural and dynamic disorder, not ionic trapping, controls charge transport in highly doped conducting polymers

Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of the dopant counter-ions. Here, we present a combined experimental and theoretical study rebutting this belief. Using a newly developed doping technique, we find the conductivity of several classes of high-mobility conjugated polymers to be strongly correlated with paracrystalline disorder but poorly correlated with ionic size, suggesting that Coulomb traps do not limit transport. A general model for interacting electrons in highly doped polymers is proposed and carefully parameterized against atomistic calculations, enabling the calculation of electrical conductivity within the framework of transient localisation theory. Theoretical calculations are in excellent agreement with experimental data, providing insights into the disordered-limited nature of charge transport and suggesting new strategies to further improve conductivities

Structural and dynamic disorder, not ionic trapping, controls charge transport in highly doped conducting polymers

Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of the dopant counter-ions. Here, we present a combined experimental and theoretical study rebutting this belief. Using a newly developed doping technique, we find the conductivity of several classes of high-mobility conjugated polymers to be strongly correlated with paracrystalline disorder but poorly correlated with ionic size, suggesting that Coulomb traps do not limit transport. A general model for interacting electrons in highly doped polymers is proposed and carefully parameterized against atomistic calculations, enabling the calculation of electrical conductivity within the framework of transient localisation theory. Theoretical calculations are in excellent agreement with experimental data, providing insights into the disordered-limited nature of charge transport and suggesting new strategies to further improve conductivities

Impact of social determinants on antiretroviral therapy access and outcomes entering the era of universal treatment for people living with HIV in Italy

Background: Social determinants are known to be a driving force of health inequalities, even in high income countries. Aim of our study was to determine if these factors can limit antiretroviral therapy (ART) access, outcome and retention in care of people living with HIV (PLHIV) in Italy. Methods: All ART naïve HIV+ patients (pts) of Italian nationality enrolled in the ICONA Cohort from 2002 to 2016 were included. The association of socio-demographic characteristics (age, sex, risk factor for HIV infection, educational level, occupational status and residency area) with time to: ART initiation (from the first positive anti-HIV test), ART regimen discontinuation, and first HIV-RNA < 50 cp/mL, were evaluated by Cox regression analysis, Kaplan Meier method and log-rank test. Results: A total of 8023 HIV+ pts (82% males, median age at first pos anti-HIV test 36 years, IQR: 29-44) were included: 6214 (77.5%) started ART during the study period. Women, people who inject drugs (PWID) and residents in Southern Italy presented the lowest levels of education and the highest rate of unemployment compared to other groups. Females, pts aged > 50 yrs., unemployed vs employed, and people with lower educational levels presented the lowest CD4 count at ART initiation compared to other groups. The overall median time to ART initiation was 0.6 years (yrs) (IQR 0.1-3.7), with a significant decrease over time [2002-2006 = 3.3 yrs. (0.2-9.4); 2007-2011 = 1.0 yrs. (0.1-3.9); 2012-2016 = 0.2 yrs. (0.1-2.1), p < 0.001]. By multivariate analysis, females (p < 0.01) and PWID (p < 0.001), presented a longer time to ART initiation, while older people (p < 0.001), people with higher educational levels (p < 0.001), unemployed (p = 0.02) and students (p < 0.001) were more likely to initiate ART. Moreover, PWID, unemployed vs stable employed, and pts. with lower educational levels showed a lower 1-year probability of achieving HIV-RNA suppression, while females, older patients, men who have sex with men (MSM), unemployed had higher 1-year risk of first-line ART discontinuation. Conclusions: Despite median time to ART start decreased from 2002 to 2016, socio-demographic factors still contribute to disparities in ART initiation, outcome and durability

Displacement of polarons by vibrational modes in doped conjugated polymers

Organic pi-conjugated polymers are deemed to be soft materials with strong electron-phonon coupling, which results in the formation of polarons, i.e., charge carriers dressed by self-localized distortion of the nuclei. Universal signatures for polarons are optical resonances below the band gap and intense vibrational modes (IVMs), both found in the infrared (IR) spectral region. Here, we study p-doped conjugated homo-and copolymers by combining first-principles modelling and optical spectroscopy from the far-IR to the visible. Polaronic IVMs are found to feature absorption intensities comparable to purely electronic transitions and, most remarkably, show only loose resemblance to the Raman or IR-active modes of the neutral polymer. The IVM frequency is dramatically scaled down (up to 50%) compared to the backbone carbon-stretching modes in the pristine polymers. The very large intensity of IVMs is associated with displacement of the excess positive charge along the backbone driven by specific vibrational modes. We propose a quantitative picture for the identification of these polaron shifting modes that solely based on structural information, directly correlates with their IR intensity. This finding finally discloses the elusive microscopic mechanism behind the huge IR intensity of IVMs in doped polymeric semiconductors