Unmanned Aerial Vehicle (UAV)-based remote sensing to monitor grapevine leaf stripe disease within a vineyard affected by esca complex

Foliar symptoms of grapevine leaf stripe disease (GLSD, a disease within the esca complex) are linked to drastic alteration of photosynthetic function and activation of defense responses in affected grapevines several days before the appearance of the first visible symptoms on leaves. The present study suggests a methodology to investigate the relationships between high-resolution multispectral images (0.05 m/pixel) acquired using an Unmanned Aerial Vehicle (UAV), and GLSD foliar symptoms monitored by ground surveys. This approach showed high correlation between Normalized Differential Vegetation Index (NDVI) acquired by the UAV and GLSD symptoms, and discrimination between symptomatic from asymptomatic plants. High-resolution multispectral images were acquired during June and July of 2012 and 2013, in an experimental vineyard heavily affected by GLSD, located in Tuscany (Italy), where vines had been surveyed and mapped since 2003. Each vine was located with a global positioning system, and classified for appearance of foliar symptoms and disease severity at weekly intervals from the beginning of each season. Remote sensing and ground observation data were analyzed to promptly identify the early stages of disease, even before visual detection. This work suggests an innovative methodology for quantitative and qualitative analysis of spatial distribution of symptomatic plants. The system may also be used for exploring the physiological bases of GLSD, and predicting the onset of this disease.

Unmanned Aerial Vehicle (UAV)-based remote sensing to monitor grapevine leaf stripe disease within a vineyard affected by esca complex

Foliar symptoms of grapevine leaf stripe disease (GLSD, a disease within the esca complex) are linked to drastic alteration of photosynthetic function and activation of defense responses in affected grapevines several days before the appearance of the first visible symptoms on leaves. The present study suggests a methodology to investigate the relationships between high-resolution multispectral images (0.05 m/pixel) acquired using an Unmanned Aerial Vehicle (UAV), and GLSD foliar symptoms monitored by ground surveys. This approach showed high correlation between Normalized Differential Vegetation Index (NDVI) acquired by the UAV and GLSD symptoms, and discrimination between symptomatic from asymptomatic plants. High-resolution multispectral images were acquired during June and July of 2012 and 2013, in an experimental vineyard heavily affected by GLSD, located in Tuscany (Italy), where vines had been surveyed and mapped since 2003. Each vine was located with a global positioning system, and classified for appearance of foliar symptoms and disease severity at weekly intervals from the beginning of each season. Remote sensing and ground observation data were analyzed to promptly identify the early stages of disease, even before visual detection. This work suggests an innovative methodology for quantitative and qualitative analysis of spatial distribution of symptomatic plants. The system may also be used for exploring the physiological bases of GLSD, and predicting the onset of this disease.

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Developing an innovative tool to enhance the biological activity of active substances for the control of fungal diseases in Vitis vinifera L.

Ce travail a consisté en l'étude l'application du phosphate de calcium comme système de transporteur (" drug delivery ") pour la protection de la vigne (Vitis vinifera L.). Ce biomatériau a été étudié avec succès dans le domaine médical, de la fonctionnalité du phosphate de calcium avec des molécules anticancéreuses, à la mise au point d'un dentifrice innovant. Des essais préliminaires dans le contrôle des maladies fongiques de la vigne ont révélé des résultats prometteurs.Dans ce contexte, l'hydroxyapatite inorganique et biomimétique a été étudié en tant que système transporteur potentiel de substances bioactives autorisées en agriculture biologique pour la protection des plantes. À travers une approche multidisciplinaire, l'objectif de l'étude était d'évaluer l'efficacité de l'hydroxyapatite dans l'amélioration de l'activité biologique des composés de cuivre(II) pour lutter contre des maladies fongiques telles que le mildiou et les maladies du bois. Cette étude a pour ambition de contribuer à l'optimisation de la distribution et de la persistance des substances bioactives dans les tissus végétaux, y compris vasculaires, où des pathogènes nocifs peuvent se développer ainsi qu'à la réduction des quantités de fongicides.Cette recherche a ainsi permis de (i) comprendre l'interaction entre le système transporteur, la substance fonctionnelle et les tissus de la vigne ; (ii) démontrer le mécanisme sur lequel l'efficacité supérieure de la substance fonctionnelle est basé ; (iii) recueillir de nouvelles informations sur les mécanismes impliqués dans l'expression des symptômes des maladies du bois en étudiant les réactions de défense des plantes induites par les traitements.The research investigates the application of biomimetic calcium phosphate as innovative delivery system for grapevine (Vitis vinifera L.) protection purposes. This smart material was successfully studied in the biomedical field, from the functionalization of biomimetic calcium phosphate with anti-cancer molecules for localized releases, to the development of an innovative toothpaste for oral hygiene. Preliminary assays to implement the control of the grapevine fungal diseases, have revealed promising results. In this framework, the biomimetic inorganic hydroxyapatite was investigated as potential delivery system of bioactive substances allowed in organic agriculture for plant protection.Through a multidisciplinary approach, the study was aimed to evaluate the efficiency of hydroxyapatite in enhancing the biological activity of copper(II) compounds, on the control of relevant common diseases, like downy mildew, and complex fungal diseases, such as the grapevine trunk diseases. This aim is related to further ambitious goals: the significant reduction of the fungicides amounts applied in plant protection and the optimization of the distribution and persistence of the bioactive substances in the plant tissues, including the vascular ones, where harmful pathogens can develop. Overall, the experimental activities allowed: (i) to understand the interaction between delivery system, functional substance and grapevine tissues; (ii) to demonstrate the mechanism on which the higher efficacy of the functional substance is based; (iii) to collect new information on the mechanisms involved in the symptoms expression by studying the plant defense reactions induced by the treatments

Higher-order organization of multivariate time series

Time series analysis has proven to be a powerful method to characterize several phenomena in biology, neuroscience and economics, and to understand some of their underlying dynamical features. Several methods have been proposed for the analysis of multivariate time series, yet most of them neglect the effect of non-pairwise interactions on the emerging dynamics. Here, we propose a framework to characterize the temporal evolution of higher-order dependencies within multivariate time series. Using network analysis and topology, we show that our framework robustly differentiates various spatiotemporal regimes of coupled chaotic maps. This includes chaotic dynamical phases and various types of synchronization. Hence, using the higher-order co-fluctuation patterns in simulated dynamical processes as a guide, we highlight and quantify signatures of higher-order patterns in data from brain functional activity, financial markets and epidemics. Overall, our approach sheds light on the higher-order organization of multivariate time series, allowing a better characterization of dynamical group dependencies inherent to real-world data