Dipartimento di Biologia, Ecologia e Scienze della Terra - Tesi di dottorato

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Questa collezione raccoglie le Tesi di Dottorato afferenti al Dipartimento Dipartimento di Biologia, Ecologia e Scienze della Terra dell'Università della Calabria.

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End date: 2019Has files: Yes

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    Procedure sinottiche di calibrazione di analisi condotte mediante interferometria radar satellitare su reti di infrastrutture urbane e stradali .
    (2009-02-04) Gerardo, Fortunato; Ferrucci, Fabrizio; Deffontaines, Benoit;
    L’étude ci-dessous illustre les résultats d’une activité expérimentale basée sur des couples d’images ERS et ENVISAT, déroulée dans l’Italie du Sud et en particulier en Calabre centreméridionale pour la période 1998-2000 (ERS) et jusqu’à 2005 (ENVISAT). En particulier, les techniques d’interférométrie SAR différentielles se sont montrées comme un outil important pour différentes applications et pour la détection de phénomènes distinct. Les données dérivées constituent un élément important pour supporter l’analyse et intégrer les connaissances d’un territoire comme celui de la Calabre Central qui, paradoxalement encore aujourd’hui, n’a été pas objet d’études géologiques détaillées suffisamment fines bien que les chroniques reportent plusieurs faits majeurs d’ « instabilité gravitaire ». L’objectif principal du travail a été la détection de subsidences, de glissements de terrain et l’évaluation générale des conditions du risque pour une zone régionale stratégiquement très important tel que la « Piana di Lamezia » à travers l’utilisation de donnés dérivées de l’analyse interférométrique SAR et leur intégration dans un SIG. Puis, on a voulu vérifier si la production de « donnés accessoires », toujours dérivées du processing SAR (cartographie ILU), sont exploitables et utiles à intégrer, en l’améliorant, la cartographie thématique et la bibliographie géologique-technique existantes. Après avoir présenté synthétiquement les principes des techniques utilisées et l’illustration de certaines approches originales dans leur implémentation pour la réduction des problèmes générales de bruit, on a montrés les résultats de leur application pour des thématismes. En particulier nous avons focalisé l’attention sur les zones urbaines et l’environnements des villes de Vibo Valentia et Lamezia Terme et sur le réseau des infrastructures présentes (ligne ferroviaire Tirrena Inferiore, autoroute A3 Salerno-Reggio Calabria et aéroport Sant’Eufemia de Lamezia Terme). Les exemples choisis constituent le prototype des petites villes caractéristiques de l’Italie méridionale avec des agglomérations urbaines modestes situées dans des zones qui parfois encore restent rurales et surtout avec des passages nets à des terrains à haut taux de couverture végétale. Les deux villes, toutefois, maintiennent des particularités étant Lamezia Terme placé dans un graben tectonique où il y a des évidences d’une tectonique active avec subsidence généralisée et Vibo Valentia sur un horst où le soulèvement néotectonique régional montre une accélération des processus de démantèlement des versants. Finalement, ce travail montre que l'interférométrie radar différentielle est un outil opérationnel pour l'étude des déformations actives dans ce territoire. Si le travaille a porté sur la standardisation d’une procédure opérationnelle avec l’intégration d’un logiciel expérimental, les apports de la technique concernent à la fois la localisation, la caractérisation et la quantification des phénomènes affectant la surface topographique. L'ensemble des informations obtenues fournit des indications inédites et précieuses pour la compréhension de certains phénomènes et leur modélisation. L’analyse qualitative et semi-quantitative des zones relatives à l’aéroport Sant’Eufemia de Lamezia Terme et à la zone urbaine de Vibo Valentia pose de nouvelles questions par rapport au déclenchement de phénomènes d’instabilités géologiques par exemple pendant des phénomènes sismiques et donc aussi pas rapport à la gestion de situation de risque par la protection civil. Pour ce qui concerne l’apport direct de la technique de l’interférométrie SAR différentielle au control des infrastructures, elle semble résulter actuellement adapte que pour un leur étude indirect. En effet, l’utilisation d’images dérivées par les satellites européens ERS et ENVISAT, ne permet pas de résoudre par exemple les problématiques liées par exemple à l’extension des cibles. Actuellement, n’étant pas complètement opérationnels les nouveaux satellites SAR caractérisés pas une résolution métrique et/ou sub-métrique, une analyse plus fine ne serait possible qu’avec l’utilisation de la technique des Permanent Scatterers qu’il faudrait développer maintenaient ici.
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    Ruolo del sistema Glutammatergico nella plasticità neuronale amigdalare del Mesocricetus auratus
    (2008) Granata, Teresa; Canonaco, Marcello
    La plasticità sinaptica è un meccanismo neuronale alla base di funzioni complesse del Sistema Nervoso Centrale, come l’apprendimento e la memoria. Tali funzioni sono associate a eventi di potenziamento e depressione sinaptici necessari ad evitare che tutte le sinapsi vadano incontro a saturazione e prevenire cicli di feedback positivo tra l’attività della rete di neuroni e la forza sinaptica. I neuroni di per sé regolano le trasmissioni eccitatorie tramite la variazione del numero e della composizione sinaptica di alcuni sistemi recettoriali come quello glutammatergico. Un ruolo centrale nel controllo della plasticità neuronale è svolto sia dai recettori dell’NMDA che dell’AMPA, costituiti entrambi da diverse subunità recettoriali la cui variazione nella composizione e reciproca organizzazione determina la formazione di recettori con caratteristiche cinetiche e farmacologiche differenti, regolando i processi di plasticità sinaptica sia durante le fasi critiche dello sviluppo encefalico che di particolari stadi fisiologici quali l’ibernazione. In virtù di ciò, il Mesocricetus auratus, un roditore ibernante facoltativo, ha rappresentato un valido modello sperimentale per gli studi neurobiologici condotti in questo lavoro. In un simile contesto, un elemento chiave della regolazione plastica è costituito dal controllo eccitazione-inibizione attraverso fenomeni di cross-talking tra i recettori glutammatergici e quelli GABAergici. In questo lavoro si è evidenziato come l’attivazione di due delle principali subunità recettoriali GABAergiche, quali α1 e α5, abbia determinato un controllo negativo sulle azioni esplicate dagli agonisti glutammatergici, sia nel contesto delle attività di feeding e drinking behavior che dal punto di vista molecolare. Infatti, la subunità α1 si oppone maggiormente alle variazioni nella capacità e/o nella volontà di assumere acqua e cibo, in seguito all’azione dell’NMDA esplicata nell’area di transizione tra l’ipotalamo e l’amigdala, sia in eutermia che in ibernazione; diversamente α5 modula il comportamento alimentare AMPA-dipendente riconducibile all’attività dell’amigdala. E’ stato, inoltre, evidenziato, mediante l’ibridazione in situ, che le maggiori variazioni trascrizionali delle subunità recettoriali glutammatergiche avvengono in seguito alla modulazione per lo più inibitoria esercitata dal sistema GABAergico principalmente attraverso la subunità α5. Questo controllo trascrizionale sarebbe il risultato di meccanismi molecolari atti a modulare l’azione di fenomeni altamente eccitatori attraverso sofisticati processi di feedback negativo: il GABA, ormai inibitorio nell’encefalo adulto, tende a silenziare l’attivazione dei recettori eccitatori, modulando la trascrizione delle loro subunità recettoriali. Un simile meccanismo assume un ruolo funzionale importante nel controllo del ciclo di ibernazione, soprattutto del risveglio, quando potrebbero innescarsi fenomeni eccitotossici simil-ischemici che indurrebbero morte cellulare.
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    Effects of long-term exposure fungicides, pyrimethanil and tebuconazole, on italian tree frog (Hyla intermedia)
    (2017-09-09) Guardia, Antonello; Tripedi, Sandro; Brunelli, Elvira
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    Implementazione di sistemi innovativi per la qualità e tracciabilità di “Healthy Food”
    (2017-07-03) Macchione, Claudia; De Cindio, Bruno; Canonaco, Marcello
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    Innovativi multiclassificatori con applicazione ai sistemi di supporto alle decisioni cliniche
    (2017-07-03) Groccia, Maria Carmela; Conforti, Domenico; Canonaco, Marcello
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    Impact of DNA methylation on plant growth and development: a study on a methylation-defective mutant of Arabidopsis thaliana
    (2017-06-09) Forgione, Ivano; Bruno, Leonardo; Van Lijsebettens, Mieke
    Epigenetic modifications of DNA contribute to chromatin remodeling process and gene expression regulation playing a relevant role on the development of eukaryotic organisms. DNA methylation is an important epigenetic mark consisting in the addition of a methyl group on cytosine bases, which is observed in most of the organisms at the different evolution levels. In plants, DNA methylation is controlled by several genetic pathways, encoding different methyltransferases which act on different sequence contexts. Targets for cytosine DNA methylation in plant genomes are CG, CHG and CHH (H is A, T, C) sequences. The plant DNMT1-homolog METHYLTRANSFERASE1 (MET1) maintains DNA methylation at CG sites, whereas the DNMT3 homolog DOMAINS REARRANGED METHYLASE 1 and 2 (DRM1 and DRM2) are responsible for the de novo methylation in all sequence contexts. In addition, the plant-specific CHROMOMETHYLASE3 (CMT3) is responsible for DNA maintenance methylation at CHG sites, as well as at a subset of CHH sites. In plants DNA methylation is involved in diverse biological processes. Loss of methylation in the Arabidopsis thaliana mutants met1 and ddm1 (decrease in DNA methylation 1) causes several developmental abnormalities. Similarly, combined mutations in the DRMs and CMT3 genes induce pleiotropic defects in plants. Here, we used the Arabidopsis thaliana triple mutant drm1 drm2 cmt3, defective in DNA methylation to get deeper insight into the correlation between DNA methylation and plant growth. We identified novel developmental defects of the triple mutant dealing with the agravitropic response of the root and an altered differentiation pattern of the leaf which also exhibits a curly shape. Confocal microscopy of mutant transgenic lines expressing DR5:GFP reporter gene allowed us to verify that the loss of DNA methylation impacts on the accumulation and distribution of auxin from embryo to adult plant. The expression of auxin-related genes has been also found to be altered in drm1 drm2 cmt3 mutant. Furthermore, through an optimized and implemented protocol of comparative analysis of genomic methylated regions based on MeDIP-qPCR, we provide evidence about the direct and organ-specific modulation of auxin-related genes through DNA methylation process. The epigenetic mechanisms interplay with each other rather than work independently to modulate gene function. Accordingly, in our study we provide a novel evidence of the crosstalk between DNA methylation status and histone modification. Indeed, in the drm1 drm2 cmt3 mutant the overexpression of CLF gene, a component of PCR2 complex that performs trimethylation of histone H3 lysine 27, was accompanied by a high level of histone methylation, as evaluated through ChIP-qPCR analysis, and by a concomitant down-regulation of genes target of PRC2 complex action. Thus, the results obtained in these three years of PhD course are encouraging and may open new perspectives in the study of the DNA methylation in plants.
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    Aspetti genetici dell'evoluzione linguistica nelle popolazioni umane: un'analisi comparativa e interdisciplinare
    (2017-07-12) Vigna, Mara; Pantano, Pietro; Passarino, Giuseppe; Dato, Serena
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    Stima della produzione solida in bacini idrografici con differenti caratteristiche mediante l'applicazione del modello EPM
    (2017-07-12) Vacca, Carmine; Pantano, Pietro Salvatore; Dominici, Rocco; Mao, Luca
    In order to increase the knowledge of sediment production and transport at the river basin scale, the research aims at the creation of a GIS project based on the multiparametric equation related to the potential erosion model EPM (Gavrilovic, 1988). The GIS allows the remote sensing data (DEM, satellite images, aerial photos etc.) to be associated with the informations detected on field. The interaction between different thematic layers allows to obtain, in an analytical way, a cartographic and a numeric output as database. These data storage are easily consulted and implemented, making the use of GIS essential for proper spatial planning. Starting from this methodological assumption, the EPM Model was applied for a certain number of catchment areas, in different geographic contexts, to better characterize the input data as a function of the output data. The output model has been calibrated and validated by comparing the experimental data obtained with real estimates of sediment transport, suspend load and bed load, of an Alpine Basin (Rio Cordon) and a Chilean Basin (Estero Morales), and with estimates of silting of dams, located in the Alpine Arc and along the Southern Apennines. The implementation of a connectivity index (degree of linkage between sediment sources and downstream areas) has led to the individuation of the volume of material that can feed an hypothetical coastal physiographic unit or can cause problems to an artificial reservoir. This more efficient model was applied to three test basin located in the Ionian (F.ra Saraceno e Stilaro) and Tyrrhenian (F.ra Sfalassà) Calabria areas. The versatility of GIS platforms and the data obtained from the EPM Model enable us to obtain a connective tool easily developable through the time, which permits the interaction between individuals and institutions in order to perform a proper management of the areas particularly vulnerable from the hydrogeological point of view
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    Modeling of biological permeable reactive barriers
    (2017-07-11) Arias Arias, Fabian Ernesto; Pantano, Pietro; Straface, Salvatore; Molinari., Raffaele
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    Due pesi e due misure: differenze di genere nella Malattia di Alzheimer
    (2017-07-12) Notaro, Patrizia; Pantano, Pietro; Passarino, Giuseppe; Bruni, Amalia C.
    Starting from the particular female exposure to Alzheimer’s disease (AD), the aim of the study was to investigate gender differences in the onset and evolution. 1925 medical records of AD patients, diagnosed with NINCDS-ADRDA criteria, were digitalized in order to extrapolate data. The mean age of the sample was 71 years, 57 years for early onset patients and 75 years for late onset, with duration of the disease around 9 years. Data taken into account and differentiated for gender were: prevalence and onset of the disease; time elapsed between the onset and the first visit, the duration of follow-up and the duration of disease; the educational level, cardiovascular and metabolic risk factors. MMSE score was considered at T0 (first visit), T1 (2yrs>T0) and T2 (4yrs>T0). A checklist of symptoms and signs, extrapolated from the cognitive-behavioral anamnesis, was then analyzed. It was furthermore calculated the genotype frequency and the allele frequency on a sample of 912 patients. IBM SPSS 20 statistics software was used (significance was given by p <0.05). Results highlighted that women were more represented in the cohort (67.1%) and in the early onset group (81.6%, p=0.008). There was no gender differences in the time elapsed from symptoms onset to the first visit (4 years), in the follow-up period (4 years) and in the duration of disease (9 years). Women were more cognitively impaired at T0 with 15.9+5.9 MMSE score vs 17+6.5 male score, while men seemed to decline faster at T2, -3.85+4.66 vs -2.93+4.39. Women had a lower level of education 5.6 years vs 6.51 years of men (p=0.000) and presented a higher comorbidity: dysthyroidism (p=0.000), cholesterol (p=0.000) hypertension (p=0.000) and a higher incidence of depression (p=0.000) while men were more statistically represented for irritability (p=0.000). Signs extrapolated from the cognitive-behavioral anamnesis have revealed a higher percentage of man for language impairment (p=0.000), behavioral symptoms (p=0.009), apraxia (p=0.005), spatial disorientation (p=0.006) and calculus impairment (p=0.035). APOE results were not representative in terms of gender differences but confirmed a possible impact of the allele ε4 on cognitive decline. Results have outlined a female patient highly represented in the sample, less educated, with a worse cognitive impairment and more exposed to comorbidity. Men seemed to impair faster in the first 2 years from onset, presenting a more aggressive picture. Furthermore, the diagnosis of the disease for the entire cohort delays of 3 years compared to the international and national mean of time elapsed from onset to first visit, which is about only 1 year The particular exposure of women to dementia and the different evolutionary impact of neurodegenerative diseases, from a gender point of view, still require ample studies and in-depth observations. In particular, the identification of specific gender aspects may be a valuable aid for a more timely identification of diseases and their better management.