67 research outputs found
Caratterizzazione geochimica e architettura deposizionale dei depositi tardo-Quaternari della Pianura di Pisa (Toscana)
Il presente lavoro di tesi si inserisce allâinterno di un piĂč ampio lavoro di ricerca, attualmente in corso, sullâarchitettura stratigrafico deposizionale dei depositi tardo-Quaternari (ultimi 100.000 anni) della pianura di Pisa condotto dalla collaborazione tra il Dipartimento di Scienze della Terra dellâUniversitĂ di Pisa ed il Dipartimento di Scienze della Terra e Geologico-Ambientale dellâUniversitĂ di Bologna.
Gli studi realizzati hanno portato allâindividuazione nel sottosuolo della pianura di una paleovalle incisa e del suo riempimento e di tracciarne le tappe evolutive fondamentali.
In questo contesto, si inserisce lo studio stratigrafico e geochimico di alcuni sondaggi realizzati nella pianura di Pisa, allo scopo di verificare, affinare e dettagliare il quadro stratigrafico e deposizionale ed, in particolare, di fornire ulteriori informazioni di dettaglio sullâevoluzione della paleovalle e del suo riempimento.
Tra i sondaggi a carotaggio continuo condotti nella pianura, ai fini del presente lavoro, ne sono stati selezionati tre, aventi diversa collocazione rispetto al corpo della paleovalle (depocentrale, esterno e laterale al corpo della valle), uno dei quali (M1) oggetto della collaborazione tra il Dipartimento di Pisa e di Bologna e giĂ pubblicato, e del quale sono stati utilizzati dati geochimici inediti del Dipartimento di Scienze della Terra e Geologico-Ambientale di Bologna.
Gli altri due sondaggi (P2 ed S1) sono stati oggetto di analisi stratigrafica e geochimica. Le analisi geochimiche XRF sono state condotte su un totale di 54 campioni provenienti dai due sondaggi, per la determinazione degli elementi maggiori (SiO2, Al2O3, TiO2, CaO, MnO, MgO, Na2O, K2O, Fe2O3, P2O5 ) e degli elementi in tracce (Sc,V, Cr, Cu, Co, Zn, Rb, Nb, Ce, Zr, Ni, Ba, La, Th, S, As, Ga, Y).
I dati ottenuti dalle analisi sono stati elaborati utilizzando profili di concentrazione degli elementi lungo la verticale dei sondaggi e diagrammi di variazione binari rispetto allâallumina.
Attraverso i profili di concentrazione sono state caratterizzate geochimicamente le varie porzioni dei sondaggi, mentre attraverso i diagrammi binari sono stati evidenziati i trend di relazione esistenti tra i vari elementi e lâallumina. Nei diagrammi binari sono stati inseriti anche dati inediti del Dipartimento di Scienze della Terra e Geologico Ambientali dellâUniversitĂ di Bologna relativi a sedimenti attuali del fiume Arno e del fiume Serchio e dati disponibili in letteratura per alcune delle rocce affioranti nei bacini dellâArno e del Serchio. Questo ha consentito il confronto fra i dati geochimici dei sondaggi e dati inerenti fiume Arno, fiume Serchio ed alcune rocce affioranti nei loro bacini.
Lo scopo del confronto Ăš stato quello di determinare le provenienze dei depositi attraversati dai sondaggi, in modo da ottenere maggiori indicazioni sulla evoluzione paleogeografica dellâarea di studio.
I risultati ottenuti hanno consentito di confermare, in generale, il quadro stratigrafico deposizionale, evidenziando un maggior grado di complessitĂ .
In sintesi i dati acquisiti hanno consentito di i) distinguere una porzione di sedimenti incisa dalla paleovalle, con composizione geochimica diversa da Arno e Serchio, ii) di riconoscere delle oscillazioni composizionali allâinterno del riempimento della paleovalle, riconducibili comunque ad Arno e Serchio, iii) ed infine di riconoscere una composizione variabile Arno-Serchio per la porzione di depositi al di sopra del riempimento
THE UPPER PLEISTOCENE âISOLA DI COLTANO SANDSâ 1 (ARNO COASTAL PLAIN, TUSCANY ITALY): REVIEW OF STRATIGRAPHIC DATA ANDTECTONIC IMPLICATIONS FOR THE SOUTHERN MARGIN OF THE VIAREGGIO BASIN
We present and discuss previously published stratigraphic and chronological (mainly
archaeological remains) data about the âIsola di Coltano Sandsâ(ICS), with the support of
unpublished core stratigraphies and taking into account the geological frame of the Arno
coastal plain.
ICS outcrops in the southern portion of the extensional Viareggio Basin, forming three
isolated small-sized reliefs rising up to 15 m above the present-day Arno coastal plain on both
sides of the Arno River.
We document that the deposits outcropping north of the Arno River (Palazzetto site)
reasonably belong to the Holocene prograding beach-ridge system to which they are
physically juxtaposed. Indeed, both sedimentological and morphological characteristics
indicate that the Palazzetto sands were exclusively formed by wind-related processes, likely
occurred during the late Holocene according to the presence of Eneolithic artefacts.
Conversely, the common presence of Mousterian artefacts at the Castagnolo and Coltano sites, located south of the Arno River, documents an age older than 40 kyr (upper Pleistocene) for
these reliefs. Moreover, new stratigraphic data show that ICS are constituted by alluvial
deposits with evidences of repetitive fluvial erosion episodes. All these features,, indicate that
ICS can be reasonably included into the Late Pleistocene Vicarello Formation, widely
outcropping along the southern margin of the Leghorn Hills. In this context, an estimated age
ranging between MIS 6 and MIS 3 can be hypothesized for the ICS.
However, the occurrence of Upper Pleistocene reliefs formed by alluvial deposits (Coltano and
Castagnolo sites) in the southern portion of the Arno coastal plain seems to conflict with the
acknowledged interpretation of the area as an extensional, subsiding setting. Moreover, the sharp morphological boundary dividing the flat Holocene coastal plain from the Quaternary
Leghorn Hills is roughly coincident with the SW-NE transpressive fault (Sillaro line) that
subdivides the subsiding area (Viareggio Basin, to which the Arno plain belongs) from the
uplifting area (Leghorn mounts).
Thus, our review of the available stratigraphic and chronological data strongly suggests the occurrence of a geological connection between the southern portion of the Arno coastal plain,
specifically of the Castagnolo and Coltano reliefs, and the Leghorns Hills where the Vicarello
Formation outcrops. This connection, which may have strong consequences on the geotectonic
interpretation of the study area, and the formation 50 age of ICS needs to be better
investigated in the future with new high-resolution tectonic and absolute chronological data
The Remote Sensing-Stratigraphic Approach Applied to the Reconstruction of Holocene Sedimentary Evolution in Coastal Areas: Case Studies from Arno and Po Delta Plains (Italy)
The growing availability of open-access databases, made the RS data and analyses to be increasingly employed in several geological research areas, including Quaternary and Environmental Geology. Despite the frequent use of the RS in alluvial-coastal plains paleohydrographic reconstruction, especially to identify stagnant versus well-drained areas (i.e., past wetlands and paleochannels, respectively) by means of brightness contrasts on images, the relationship between surface RS-derived traces and shallow subsurface stratigraphy remains underexplored.
The present PhD thesis represents a contribution to this open issue, through the application of a multidisciplinary approach integrating RS (optical multi/hyperspectral images and DTM LiDAR) with sedimentologic and stratigraphic field data in the study of the Holocene evolution of paleodrainages from two coastal-deltaic areas: San Rossore site (SR-Arno plain) and Mezzano Valley (MV-Po plain).
The analyses of 27 scenes from Landsat, ASTER, Sentinel2a and Hyperion allowed to identify paleochannels traces in the two sites. Field surveys and soil sampling campaigns performed on selected traces to define their surface sedimentological and optical characteristics, invariabily highlighted silty-clayey composition. A cross-reference was performed between traces and the shallow subsurface (i.e., uppermost 10 m) through the collection of 26 auger and continuous core data on which facies analysis, 14C dating and stratigraphic correlations were performed that allow to identify buried (2-4m bgl) channels. Their surface visibility, connected to the soil moisture distribution, resulted to be influenced mainly by the distribution of organic-rich deposits and/or by the shallow subsurface stratigraphic architecture. The âstratigraphic calibrationsâ extendended along RS-detected traces suggested that during the early highstand (6000-3000 yr cal BP) the MV experienced a tidally-influenced lagoon phase with the development of 2 networks of âtidal-channelsâ, whose formation was favored by local factors (suh as low topographic gradient and continuous beachridges development) while, the Pisa lagoon, in the same time-interval, was gradually filled by distributary channels
Litho-sedimentological and morphodynamic characterization of the Pisa Province coastal area (northern Tuscany, Italy)
In this paper litho-sedimentological and morphodynamic maps of the coastal sector belonging to the Pisa Province are presented as an example of how increasing the accessibility to data on lithology, sedimentology, and morphodynamics may lead to a better approach to coastal management. The database used to build the maps includes an original rendering of remote sensing data (aerial imagery) and new field data (geologic survey), as well as data retrieved from the scientific literature (grain-size and past coastline positions). The maps show that the geometry of beach ridges is an indication of the evolution of the Arno River delta in the last 3000 years, highlighting the relationships between geological aspects and morphodynamic features. The maps represent the synthesis of different data available in the database, and they may be a useful support to coastal management as they are more easily understandable and straightforward than the database from which are created
Angiogenic and angiostatic factors in systemic sclerosis: increased levels of vascular endothelial growth factor are a feature of the earliest disease stages and are associated with the absence of fingertip ulcers
To examine whether the lack of sufficient neoangiogenesis in systemic sclerosis (SSc) is caused by a decrease in angiogenic factors and/or an increase in angiostatic factors, the potent proangiogenic molecules vascular endothelial growth factor (VEGF) and basic fibroblast growth factor, and the angiostatic factor endostatin were determined in patients with SSc and in healthy controls. Forty-three patients with established SSc and nine patients with pre-SSc were included in the study. Serum levels of VEGF, basic fibroblast growth factor and endostatin were measured by ELISA. Age-matched and sex-matched healthy volunteers were used as controls. Highly significant differences were found in serum levels of VEGF between SSc patients and healthy controls, whereas no differences could be detected for endostatin and basic fibroblast growth factor. Significantly higher levels of VEGF were detected in patients with Scl-70 autoantibodies and in patients with diffuse SSc. Patients with pre-SSc and short disease duration showed significant higher levels of VEGF than healthy controls, indicating that elevated serum levels of VEGF are a feature of the earliest disease stages. Patients without fingertip ulcers were found to have higher levels of VEGF than patients with fingertip ulcers. Levels of endostatin were associated with the presence of giant capillaries in nailfold capillaroscopy, but not with any other clinical parameter. The results show that the concentration of VEGF is already increased in the serum of SSc patients at the earliest stages of the disease. VEGF appears to be protective against ischemic manifestations when concentrations of VEGF exceed a certain threshold level
Covid-19 And Rheumatic Autoimmune Systemic Diseases: Role of Pre-Existing Lung Involvement and Ongoing Treatments
The Covid-19 pandemic may have a deleterious impact on patients with autoimmune systemic diseases (ASD) due to their deep immune-system alterations
A patient-driven registry on Behçetâs disease: the AIDA for patients pilot project
IntroductionThis paper describes the creation and preliminary results of a patient-driven registry for the collection of patient-reported outcomes (PROs) and patient-reported experiences (PREs) in Behçetâs disease (BD).MethodsThe project was coordinated by the University of Siena and the Italian patient advocacy organization SIMBA (Associazione Italiana Sindrome e Malattia di Behçet), in the context of the AIDA (AutoInflammatory Diseases Alliance) Network programme. Quality of life, fatigue, socioeconomic impact of the disease and therapeutic adherence were selected as core domains to include in the registry.ResultsRespondents were reached via SIMBA communication channels in 167 cases (83.5%) and the AIDA Network affiliated clinical centers in 33 cases (16.5%). The median value of the Behçetâs Disease Quality of Life (BDQoL) score was 14 (IQR 11, range 0â30), indicating a medium quality of life, and the median Global Fatigue Index (GFI) was 38.7 (IQR 10.9, range 1â50), expressing a significant level of fatigue. The mean Beliefs about Medicines Questionnaire (BMQ) necessity-concern differential was 0.9â±â1.1 (range â 1.8â4), showing that the registry participants prioritized necessity belief over concerns to a limited extent. As for the socioeconomic impact of BD, in 104 out of 187 cases (55.6%), patients had to pay from their own pocket for medical exams required to reach the diagnosis. The low family socioeconomic status (pâ<â0.001), the presence of any major organ involvement (pâ<â0.031), the presence of gastro-intestinal (pâ<â0.001), neurological (pâ=â0.012) and musculoskeletal (pâ=â0.022) symptoms, recurrent fever (pâ=â0.002), and headache (pâ<â0.001) were associated to a higher number of accesses to the healthcare system. Multiple linear regression showed that the BDQoL score could significantly predict the global socioeconomic impact of BD (Fâ=â14.519, OR 1.162 [CI 0.557â1.766], pâ<â0.001).DiscussionPreliminary results from the AIDA for Patients BD registry were consistent with data available in the literature, confirming that PROs and PREs could be easily provided by the patient remotely to integrate physician-driven registries with complementary and reliable information
The growth and decline of Pisa (Tuscany, Italy) up to the Middle Ages: Correlations with landscape and geology
The history of Pisa up to the Middle Ages was influenced by the local landscape. Pisa is located at the confluence of two rivers, has easy access to the sea, is surrounded by wetlands, and overlies a clay-sand substrate characterized by highly plastic clay near the ground surface. All of these characteristics have played a significant role in the history of Pisa along with socio-economic and sociopolitical conditions. Pisa is located in western Tuscany, about 15 km from the Tyrrhenian Sea, in a very flat coastal plain (Pisa plain) crossed by the meandering Arno River. The origin of Pisa dates from the 5thcentury BC when Pisa was an Etruscan settlement. In the 2ndcentury BC the Romans built Portus Pisanus harbour. Pisa was known as an important commercial and political centre in the Middle Ages and obtained the status of Maritime Republic, similar to Venice, Genoa and Amalfi. In 1284, its defeat in the battle of the Meloria against Genoa caused the beginning of the city's decline. In 1509, Pisa passed definitively under the domination of Florence. The history of Pisa was influenced by many factors related to the local landscape. It started at the confluence of two large rivers, Arno and Auser, an old branch of the Serchio River. These rivers represented a resource for transport of goods; however, they also necessitated the continuous management of hydraulic works to protect the town from floods and to avoid the formation of the wetlands. The Pisa plain was characterized by wide and numerous wetlands. Unlike other areas of Italy, the wetlands were more an economic resource than a cause of health problems like malaria or developmental complications for transport and agriculture. In any case, a network of artificial canals was built to partially drain these wetlands and impede their expansion. Its sea- and river-harbours made Pisa an important Marine Republic during the Late Middle Ages. Pisa had commercial influence on the coast of the Tyrrhenian Sea, Corsica, Sardinia and the Balearic Islands until progressive siltation and catastrophic events caused the abandonment of the harbours. Foundation problems vexed Pisa, as evidenced by the famous Leaning Tower. The problem originates from the nature of the subsurface, which is characterized by highly plastic clay layers at shallow depth; the thickest (7-8 m called pancone) occurs at about 10 m below the surface
Lettura interdisciplinare dei carotaggi: l'elaborazione di una rappresentazione integrata del log stratigrafico
The identification of a common technical language, essential for the integrated study of cores carried out in MAPPA project by a multidisciplinary researchteam, was an issue ok key importance for the success of the project. It became essential to develop a graphical tool that could represent the data resulting from the various disciplines in a syntetic and integrated manner, given the absence of a satisfactory model for our objectives
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