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Transcriptomes testiculaire et épididymaire chez le verrat : variations au cours du développement post-natal et en relation avec la fertilité / Testicular and epididymal transcriptomes in the boar : variations during post-natal development and according to fertilityGuyonnet, Benoît 19 December 2008 (has links)
Ce travail analyse à l’aide d’une puce à ADN porcine (GEO : GPL3729) comportant 9216 dépôts, les transcriptomes testiculaire et épididymaire chez des verrats adultes ainsi que leurs variations au cours du développement post-natal et en relation avec la fertilité. Cinq unités transcriptionnelles ont été mises en évidence le long de l’épididyme grâce à l’adaptation de méthodes statistiques originales. Pour un certain nombre de gènes (déjà connus ou nouveaux), cette régionalisation d’expression a été confirmée par RT-PCR et PCR en temps réel. Un début de régionalisation est présent dès l’âge d’un mois et évolue jusqu’à huit mois pour atteindre son état définitif. Pour la première fois chez une espèce de mammifères domestiques, l’existence de gènes différentiellement exprimés entre des lots d’animaux de fertilité contrastée est démontrée. / This study used a pig DNA microarray (GEO: GPL3729) including 9216 spots to analyze testicular and epididymal transcriptomes of adult boars and their variations during post-natal development and according to fertility. Five transcriptome units were defined along the epididymis using original statistical methods. For some genes (both already known and new genes), this regionalized expression was confirmed both by PCR and by real-time PCR. The beginnings of regionalization are present from one month of age and evolve to reach its definitive state at eight months of age. For the first time in a large mammal, we demonstrated the existence of differentially expressed genes in boars of contrasting fertility.
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Lateral spreading and associated slope processes in fractured rock slabsSpreafico, Margherita Cecilia <1984> 21 May 2015 (has links)
Landslides of the lateral spreading type, involving brittle geological units overlying ductile terrains, are a common occurrence in the sandstone and limestone plateaux of the northern Apennines of Italy. These instability phenomena can become particularly risky, when historical towns and cultural heritage sites built on the top of them are endangered. Neverthless, the mechanisms controlling the developing of related instabilities, i.e. toppling and rock falls, at the edges of rock plateaux are not fully understood yet. In addition, the groundwater flow path developing at the contact between the more permeable units, i.e. the jointed rock slab, and the relatively impermeable clay-rich units have not been already studied in details, even if they may play a role in this kind of instability processes, acting as eventual predisposing and/or triggering factors. Field survey, Terrestrial Laser Scanner and Close Range Photogrammetry techniques, laboratory tests on the involved materials, hydrogeological monitoring and modelling, displacements evaluation and stability analysis through continuum and discontinuum numerical codes have been performed on the San Leo case study, with the aim to bring further insights for the understanding and the assessment of the slope processes taking place in this geological context.
The current research permitted to relate the aquifer behaviour of the rocky slab to slope instability processes. The aquifer hosted in the fractured slab leads to the development of perennial and ephemeral springs at the contact between the two units. The related piping erosion phenomena, together with slope processes in the clay-shales led to the progressive undermining of the slab. The cliff becomes progressively unstable due to undermining and undergoes large-scale landslides due to fall or topple.
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Geomorphic Features Revealed by the Acquisition, Processing and Interpretation of HIgh-Resolution Seismic Reflection Profiles across a Large Debris-Flow Fan (Vinschgau/Val Venosta, Italian Alps)Maraio, Stefano <1985> January 1900 (has links)
Researches concerning the Quaternary sedimentary dynamics in the European Alps have become of increasing interest in the late decades, producing a large volume of literature. This thesis uses high-resolution seismic reflection data and seismic stratigraphic methods to examine the formation and evolution of a major alluvial/glacial fan in the eastern Italian Alps. Alluvial fan environments, often pose significant challenges for high-resolution seismic exploration, due to high heterogeneity of deposits and rugged topography. Using both non-conventional field (dense wide aperture array) and processing techniques (Common Reflection Surface stack), we were able to obtain high-quality seismic reflection and refraction images across a representative transect of Venosta Valley. By using stratigraphic, geophysical and morphologic data this work characterizes the fan and valley deposits and their evolution throughout post-glacial times. Using this information, we model the evolution of the valley fill in the framework of post-glacial climate fluctuations. The results provide an understanding of the landscape geomorphic evolution in response to the main climatic changes and also can represent a tool in policy decision regarding natural hazards.
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Anatomia, paleobiologia e filogenesi di Macrocnemus bassanii Nopcsa 1930 (Reptilia, Protorosauria) / Anatomy, paleobiology and phylogenesis of Macrocnemus bassanii Nopcsa 1930 (Reptilia, Protorosauria)Saller, Franco <1963> 15 April 2016 (has links)
Macrocnemus bassanii è un rettile diapside del Triassico medio appartenente al gruppo dei Protorosauria. Le sue principali caratteristiche sono gli arti posteriori molto più lunghi di quelli anteriori e il collo rigido e allungato. Questo lavoro ha lo scopo di chiarire alcuni aspetti ancora poco noti della sua anatomia, in particolare la struttura della regione nasale, la mobilità del quadrato e l’eventuale presenza di placche sternali e di epifisi. Inoltre si vuole comprendere la funzione del collo allungato, che è il principale enigma di questo gruppo di rettili. La sua particolare struttura è probabilmente correlata al tipo di locomozione di Macrocnemus bassanii. Ricostruire il tipo di locomozione è fondamentale per stabilire qual era il ruolo ecologico di questo rettile. Si esaminano infine i rapporti filogenetici tra Macrocnemus bassanii e gli altri taxa appartenenti al gruppo dei protorosauria. / Macrocnemus bassanii is a Middle Trias diapsid reptile that belongs to the group of the Protorosauria. Its main features are the elongated stiff neck and the hindlimbs which are much longer than the forelimbs. The aim of this study is to clarify some aspects of its anatomy that are still controversial, like the structure of the nasal region, the mobility of the quadrate, and the existence of sternal plates and epiphysis. Furthermore it is very important to understand the function of the neck. The neck is the major conundrum of this group of reptiles. Its particular structure is probably correlated to the kind of locomotion of Macrocnemus bassanii. The reconstruction of the kind of locomotion is fundamental to establish what the ecological role of this reptile was. Finally the phylogenetic relationships between Macrocnemus bassanii and the other taxa of the Protorosauria are studied.
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Stream sediments analysis for geochemical mapping of Romagna Apennines (Northern Italy): monitoring and management tool of environmental resources at various scalesLancianese, Valerio <1985> 05 May 2014 (has links)
Geochemical mapping is a valuable tool for the control of territory that can be used not only in the identification of mineral resources and geological, agricultural and forestry studies but also in the monitoring of natural resources by giving solutions to environmental and economic problems. Stream sediments are widely used in the sampling campaigns carried out by the world's governments and research groups for their characteristics of broad representativeness of rocks and soils, for ease of sampling and for the possibility to conduct very detailed sampling
In this context, the environmental role of stream sediments provides a good basis for the implementation of environmental management measures, in fact the composition of river sediments is an important factor in understanding the complex dynamics that develop within catchment basins therefore they represent a critical environmental compartment: they can persistently incorporate pollutants after a process of contamination and release into the biosphere if the environmental conditions change. It is essential to determine whether the concentrations of certain elements, in particular heavy metals, can be the result of natural erosion of rocks containing high concentrations of specific elements or are generated as residues of human activities related to a certain study area.
This PhD thesis aims to extract from an extensive database on stream sediments of the Romagna rivers the widest spectrum of informations. The study involved low and high order stream in the mountain and hilly area, but also the sediments of the floodplain area, where intensive agriculture is active. The geochemical signals recorded by the stream sediments will be interpreted in order to reconstruct the natural variability related to bedrock and soil contribution, the effects of the river dynamics, the anomalous sites, and with the calculation of background values be able to evaluate their level of degradation and predict the environmental risk.
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Hydrogeochemical monitoring and modelling of saltwater intrusion in lowlands (Ferrara, IT) / Monitoraggio idrogeochimico e modellazione numerica dei processi di salinizzazione dell'acquifero costiero ferrareseColombani, Nicolo <1977> 11 May 2015 (has links)
Because of the potentially irreversible impact of groundwater quality deterioration in the Ferrara coastal aquifer, answers concerning the assessment of the extent of the salinization problem, the understanding of the mechanisms governing salinization processes, and the sustainability of the current water resources management are urgent.
In this light, the present thesis aims to achieve the following objectives:
Characterization of the lowland coastal aquifer of Ferrara: hydrology, hydrochemistry and evolution of the system
The importance of data acquisition techniques in saltwater intrusion monitoring
Predicting salinization trends in the lowland coastal aquifer
Ammonium occurrence in a salinized lowland coastal aquifer
Trace elements mobility in a saline coastal aquifer / A causa dell'impatto potenzialmente irreversibile del deterioramento della qualità delle risorse idriche , l'obiettivo primario di questa tesi è stato quello di ottenere una comprensione quantitativa dei processi che hanno causato la salinizzazione delle acque sotterranee nella falda acquifera costiera ferrarese. In secondo luogo si è voluto indagare l’impatto che i cambiamenti climatici potranno avere sul processo di salinizzazione in atto e le eventuali conseguenze che un aumento di salinità possono avere sulla mobilizzazione di contaminanti sia maggiori che in tracce. Alla luce di quanto detto sin qui, lo studio in oggetto si propone di raggiungere i seguenti obiettivi:
- Caratterizzazione della falda acquifera costiera della pianura di Ferrara: idrologia, idrochimica ed evoluzione del sistema
- Importanza di tecniche di monitoraggio nella comprensione dei processi di salinizzazione
- L’influenza della salinizzazione sui trend di concentrazione dell’ammonio e degli elementi nell’acquifero costiero
- Previsione dei trend di salinizzazione della falda acquifera costiera
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High-resolution stratigraphy of Central and Southern Adriatic Quaternary deposits of sub-Milankovian climate change on Mediterranean circulationPiva, Andrea <1978> 07 May 2007 (has links)
This volume is a collection of the work done in a three years-lasting PhD, focused in the analysis of Central and Southern Adriatic marine sediments, deriving from the collection of a borehole and many cores, achieved thanks to the good seismic-stratigraphic knowledge of the study area.
The work was made out within European projects EC-EURODELTA (coordinated by Fabio Trincardi, ISMAR-CNR), EC-EUROSTRATAFORM (coordinated by Phil P. E. Weaver, NOC, UK), and PROMESS1 (coordinated by Serge Bernè, IFREMER, France). The analysed sedimentary successions presented highly expanded stratigraphic intervals, particularly for the last 400 kyr, 60 kyr and 6 kyr BP. These three different time-intervals resulted in a tri-partition of the PhD thesis. The study consisted of the analysis of planktic and benthic foraminifers’ assemblages (more than 560 samples analysed), as well as in preparing the material for oxygen and carbon stable isotope analyses, and interpreting and discussing the obtained dataset. The chronologic framework of the last 400 kyr was achieved for borehole PRAD1-2 (within the work-package WP6 of PROMESS1 project), collected in 186.5 m water depth. The proposed chronology derives from a multi-disciplinary approach, consisting of the integration of numerous and independent proxies, some of which analysed by other specialists within the project. The final
framework based on: micropaleontology (calcareous nannofossils and foraminifers’ bioevents), climatic cyclicity (foraminifers’ assemblages), geochemistry (oxygen stable isotope, made out on planktic and benthic records), paleomagnetism, radiometric ages (14C AMS), teprhochronology, identification of sapropel-equivalent levels (Se). It’s worth to note the good consistency between
the oxygen stable isotope curve obtained for borehole PRAD1-2 and other deeper Mediterranean records. The studied proxies allowed the recognition of all the isotopic intervals from MIS10 to MIS1 in PRAD1-2 record, and the base of the borehole has been ascribed to the early MIS11.
Glacial and interglacial intervals identified in the Central Adriatic record have been analysed in detail for the paleo-environmental reconstruction, as well. For instance, glacial stages MIS6, MIS8 and MIS10 present peculiar foraminifers’ assemblages, composed by benthic species typical of polar regions and no longer living in the Central Adriatic nowadays. Moreover, a deepening trend in the paleo-bathymetry during glacial intervals was observed, from MIS10 (inner-shelf environment) to MIS4 (mid-shelf environment).Ten sapropel-equivalent levels have been recognised in PRAD1-2 Central Adriatic record. They showed different planktic foraminifers’ assemblages, which allowed the first distinction of events occurred during warm-climate (Se5, Se7), cold-climate (Se4, Se6 and Se8) and temperate-intermediate-climate (Se1, Se3, Se9, Se’, Se10) conditions, consistently with literature. Cold-climate
sapropel equivalents are characterised by the absence of an oligotrophic phase, whereas warm-temeprate-climate sapropel equivalents present both the oligotrophic and the eutrophic
phases (except for Se1). Sea floor conditions vary, according to benthic foraminifers’ assemblages, from relatively well oxygenated (Se1, Se3), to dysoxic (Se9, Se’, Se10), to highly dysoxic (Se4, Se6, Se8) to events during which benthic foraminifers are absent (Se5, Se7). These two latter levels are also characterised by the lamination of the sediment, feature never observed in literature in such
shallow records. The enhanced stratification of the water column during the events Se8, Se7, Se6, Se5, Se4, and the concurring strong dilution of shallow water, pointed out by the isotope record, lead to the hypothesis of a period of intense precipitation in the Central Adriatic region, possibly due to a northward shift of the African Monsoon. Finally, the expression of Central Adriatic PRAD1-2 Se5 equivalent was compared with the same event, as registered in other Eastern Mediterranean areas. The sequence of substantially the same planktic foraminifers’ bioevents has
been consistently recognised, indicating a similar evolution of the water column all over the Eastern Mediterranean; yet, the synchronism of these events cannot be demonstrated. A high resolution analysis of late Holocene (last 6000 years BP) climate change was carried out for the Adriatic area, through the recognition of planktic and benthic foraminifers’ bioevents. In particular, peaks of planktic Globigerinoides sacculifer (four during the last 5500 years BP in the most expanded core) have been interpreted, based on the ecological requirements of this species, as warm-climate, arid intervals, correspondent to periods of relative climatic optimum, such as, for instance, the Medieval Warm Period, the Roman Age, the Late Bronze Age and the Copper Age. Consequently, the minima in the abundance of this biomarker could correspond to relatively cooler and more rainy periods. These conclusions are in good agreement with the isotopic and the pollen data. The Last Occurrence (LO) of G. sacculifer has been dated in this work at an average age of 550 years BP, and it is the best bioevent approximating the base of the Little Ice Age in the Adriatic. Recent literature reports the same bioevent in the Levantine Basin, showing a rather consistent age. Therefore, the LO of G. sacculifer has the potential to be extended to all the Eastern Mediterranean. Within the Little Ice Age, benthic foraminifer V. complanata shows two distinct peaks in the shallower Adriatic cores analysed, collected hundred kilometres apart, inside the mud belt environment. Based on the ecological requirements of this species, these two peaks
have been interpreted as the more intense (cold and rainy) oscillations inside the LIA. The chronologic framework of the analysed cores is robust, being based on several range-finding 14C AMS ages, on estimates of the secular variation of the magnetic field, on geochemical estimates
of the activity depth of 210Pb short-lived radionuclide (for the core-top ages), and is in good agreement with tephrochronologic, pollen and foraminiferal data. The intra-holocenic climate oscillations find out in the Adriatic have been compared with those pointed out in literature from other records of the Northern Hemisphere, and the chronologic constraint seems quite good. Finally, the sedimentary successions analysed allowed the review and the update of the foraminifers’ ecobiostratigraphy available from literature for the Adriatic region, thanks to the
achievement of 16 ecobiozones for the last 60 kyr BP. Some bioevents are restricted to the Central Adriatic (for instance the LO of benthic Hyalinea balthica , approximating the MIS3/MIS2 boundary), others occur all over the Adriatic basin (for instance the LO of planktic Globorotalia inflata during MIS3, individuating Dansgaard-Oeschger cycle 8 (Denekamp)).
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Separazione di contributi di onda piana e di campo vicino per l'inversione di dati magnetotelluricidi Giuseppe, Maria Giulia <1976> 15 June 2007 (has links)
No description available.
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Depositi torbiditici cogenetici a frane oloceniche del vulcano di Stromboli: implicazioni per la mitigazione del rischio derivante da tsunamiDi Roberto, Alessio <1978> 09 July 2007 (has links)
No description available.
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Applicazione ed integrazione di metodi di prospezione geofisica: studio idrogeofisico della Zona Insatura in condizioni idriche controllateDurante, Paolo <1977> 07 May 2007 (has links)
Il lavoro è incentrato sull’applicazione ed integrazione di differenti tecniche di indagine geofisica in campo ambientale e ingegneristico/archeologico. Alcuni esempi sono stati descritti al fine di dimostrare l’utilità delle metodologie geofisiche nella risoluzione di svariate problematiche. Nello specifico l’attenzione è stata rivolta all’utilizzo delle tecniche del Ground Penetrating Radar e del Time Domain Reflectometry in misure condotte su un corpo
sabbioso simulante una Zona Insatura. L’esperimento è stato realizzato all’interno di un’area test costruita presso l’azienda agricola dell’Università La Tuscia di Viterbo. Hanno partecipato al progetto le Università di Roma Tre, Roma La Sapienza, La Tuscia, con il supporto tecnico della Sensore&Software. Nello studio è stato condotto un approccio definito idrogeofisico al fine di ottenere informazioni da misure dei parametri fisici relativi alla Zona Insatura simulata nell’area test. Il confronto e l’integrazione delle due differenti tecniche di indagine ha offerto la possibilità di estendere la profondità di indagine all’interno del corpo sabbioso e di verificare l’utilità della tecnica GPR nello studio degli effetti legati alle variazioni del contenuto d’acqua nel suolo, oltre a determinare la posizione della superficie piezometrica per i differenti scenari di saturazione. Uno specifico studio è stato realizzato sul segnale radar al fine di stabilire i fattori di influenza sulla sua propagazione all’interno del suolo. Il comportamento dei parametri dielettrici nelle condizioni di drenaggio e di imbibizione del corpo sabbioso è stato riprodotto attraverso una modellizzazione delle proprietà dielettriche ed idrologiche sulla base della dimensione, forma e distribuzione dei granuli di roccia e pori, nonché sulla base della storia relativa alla distribuzione dei fluidi di saturazione all’interno del
mezzo. La modellizzazione è stata operata sulle basi concettuali del Differential Effective Medium Approximation.
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