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Developing numerical approaches for predicting sediment flux variations is of primary importance for understanding the evolution of ancient sediment routing systems (SRS) and quantifying the role of external forcing controls. However, it is a particularly challenging task often hampered by the lack of solid paleo-climatic, paleo-tectonic and sedimentological constraints. Mass balance-based techniques, the most used in deep-time (>107 yr), suffer the intrinsic uncertainty of the stratigraphic record, determined by the impossibility to quantify hiatuses, unconformities and sediment reworking. To overcome uncertainties, we propose an alternative workflow built on the relationships between sediment flux (Qs), geomorphological, climatic and hydrological parameters expressed via BQART modelling. We test this approach on Middle Permian-Early Triassic terrestrial sequences of the SE Germanic Basin (Franconian Basin), a region that appears relatively well preserved, where more recent tectonic inversions did not significantly alter the original basin configuration. Input variables derive from high detail paleodrainage and paleogeographic reconstructions, integrated plate modelling and structural kinematics, global circulation models and sandstone compositional signatures. Two approaches for area estimates, two climate models and two timescale resolutions are employed to simulate eight different environmental scenarios. Furthermore, we apply the probabilistic Monte Carlo Simulation to cover the probability of different outcomes and quantify the uncertainty of each input variable. All the simulations are in general agreement: Middle Permian sediment flux is steadily around 3.0 Mt yr−1, increases by 31% (4.6 Mt yr−1) in the Late Permian and by nearly 100% (7.4 Mt yr−1) across the Permian-Triassic boundary (PTB). Simulated variations of sediment load mirror changes in facies association interpreted from borehole sequences and defined by: (i) Middle-Late Permian ephemeral deposition in alluvial/fluvial fan settings, (ii) transition from sabkha to meandering depositional settings throughout the Late Permian, and (iii) onset of perennial braided deposition in the Early Triassic. Qs estimates agree with those of modern drainages under analogous environmental conditions, confirming the accuracy of the newly developed analytical workflow. Sedimentological and quantitative provenance analyses untangle the role of climate and tectonism on drainage modifications and sediment flux variations, corresponding to intensified monsoonal precipitation and the establishment of extensional tectonic regime across the PTB. Overall, this study provides new insights into the highly debated evolution of the continental sequences across the Permian-Triassic transition with strong implications for both regional and global paleoenvironmental reconstructions.

The composition of clastic sediments or sedimentary rocks is a result of source area properties, sediment generation and transport processes as well as post-depositional changes. Deciphering the provenance of clastic deposits can therefore provide valuable insights into tectonic, geomorphic, climatic and anthropogenic factors and processes shaping sedimentary systems over different temporal and spatial scales. This session welcomes contributions that investigate (1) the provenance of clastic deposits by analyzing compositional (e.g. mineralogical, geochemical) properties, (2) the processes that modify detrital signals throughout the sedimentary routing system, and (3) the relationships to internal and external forcing mechanisms. This session is co-hosted by the 'Fachsektion Sedimentologie' of the DGGV.

Dottorato di Ricerca in Scienze della Terra, XXI Ciclo, a.a. 2005-2008 Università della Calabria

Evidence indicates altered neurogenesis in neurodegenerative diseases associated with inflammation, including Alzheimer's disease (AD). Neuroinflammation and its propagation have a critical role in the degeneration of hippocampal neurons, cognitive impairment, and altered neurogenesis. Particularly, tumor necrosis factor (TNF)-α plays a central role in initiating and regulating the cytokine cascade during an inflammatory response and is up-regulated in brain of AD patients. In this study, we investigated the effects of a novel thalidomide-based TNF-α lowering drug, 3,6'-dithiothalidomide, on hippocampal progenitor cell proliferation, neurogenesis and, memory tasks after intracerebroventricular injection of β-amyloid (Aß)(1-42) peptide. Seven days after Aβ(1-42) injection, a significant proliferation of hippocampal progenitor cells and memory impairment were evident. Four weeks after Aβ(1-42) peptide injection, elevated numbers of surviving 5-bromo-2'-deoxyuridine cells and newly formed neurons were detected. Treatment with 3,6'-dithiothalidomide attenuated these Aβ(1-42) provoked effects. Our data indicate that although treatment with 3,6'-dithiothalidomide in part attenuated the increase in hippocampal neurogenesis caused by Aβ(1-42) -induced neuroinflammation, the drug prevented memory deficits associated with increased numbers of activated microglial cells and inflammatory response. Therefore, 3,6'-dithiothalidomide treatment likely reduced neuronal tissue damage induced by neuroinflammation following Aβ(1-42) injection. Understanding the modulation of neurogenesis, and its relationship with memory function could open new therapeutic interventions for AD and other neurodegenerative disorders with an inflammatory component.

BackgroundNeuroinflammation is associated with virtually all major neurodegenerative disorders, including Alzheimer’s disease (AD). Although it remains unclear whether neuroinflammation is the driving force behind these disorders, compelling evidence implicates its role in exacerbating disease progression, with a key player being the potent proinflammatory cytokine TNF-α. Elevated TNF-α levels are commonly detected in the clinic and animal models of AD.MethodsThe potential benefits of a novel TNF-α-lowering agent, 3,6′-dithiothalidomide, were investigated in cellular and rodent models of neuroinflammation with a specific focus on AD. These included central and systemic inflammation induced by lipopolysaccharide (LPS) and Aβ1–42 challenge, and biochemical and behavioral assessment of 3xTg-AD mice following chronic 3,6′-dithiothaliodmide.Results3,6′-Dithiothaliodmide lowered TNF-α, nitrite (an indicator of oxidative damage) and secreted amyloid precursor protein (sAPP) levels in LPS-activated macrophage-like cells (RAW 264.7 cells). This translated into reduced central and systemic TNF-α production in acute LPS-challenged rats, and to a reduction of neuroinflammatory markers and restoration of neuronal plasticity following chronic central challenge of LPS. In mice centrally challenged with Aβ1–42 peptide, prior systemic 3,6′-dithiothalidomide suppressed Aβ-induced memory dysfunction, microglial activation and neuronal degeneration. Chronic 3,6′-dithiothalidomide administration to an elderly symptomatic cohort of 3xTg-AD mice reduced multiple hallmark features of AD, including phosphorylated tau protein, APP, Aβ peptide and Aβ-plaque number along with deficits in memory function to levels present in younger adult cognitively unimpaired 3xTg-AD mice. Levels of the synaptic proteins, SNAP25 and synaptophysin, were found to be elevated in older symptomatic drug-treated 3xTg-AD mice compared to vehicle-treated ones, indicative of a preservation of synaptic function during drug treatment.ConclusionsOur data suggest a strong beneficial effect of 3,6′-dithiothalidomide in the setting of neuroinflammation and AD, supporting a role for neuroinflammation and TNF-α in disease progression and their targeting as a means of clinical management.

Las capas rojas triásicas de la Cobertera Tabular de la Meseta Ibérica consisten en cuerpos de arenisca de origen fluvial embebidos en sedimentos finos. Los cuerpos estudiados pertenecen a dos de las cuatro secuencias de la sucesión estratigráfica y se formaron en ambientes sedimentarios diferentes, como son: (i) depósitos de desbordamiento y depósitos canalizados (secuencia II) y (ii) llanura fluvial de tipo trenzado (secuencia IV). El estudio petrológico ha revelado que existen diferencias entre ellos en cuanto a la composición modal del esqueleto, la textura sedimentaria y los procesos diagenéticos ocurridos. La señal composicional revela una disminución del contenido en plagioclasa, que se corresponde con un aumento del contenido en fragmentos de rocas, así como una disminución en la compactación y grado de cementación de la secuencia II a la IV. La tipología y cronología de los cementos indica una profundidad de enterramiento coherente con una etapa mesodiagenética temp, The Triassic Red Beds of the Tabular Cover of the Iberian Meseta consist on fluvial sandstone bodies embedded in overbank fines. The studied deposits correspond to two of the four sequences of the stratigraphic succession and developed under different sedimentary environments as: (i) overbank and channel deposits (sequence II) and (ii) braidplain deposits (sequence IV). The petrological study has revealed the main differences between them as a function of framework composition, textural parameters and diagenetic processes. Compositional trends highlighted a decrease of plagioclase content to which correspond major content in rock fragments, as well as a minor compaction and degree of cementation from sequence II to IV. Cements types and chronology suggest a depth of burial according to an early meso-diagenesis stage

Las capas rojas triásicas de la Cobertera Tabular de la Meseta Ibérica consisten en cuerpos de arenisca de origen fluvial embebidos en sedimentos finos. Los cuerpos estudiados pertenecen a dos de las cuatro secuencias de la sucesión estratigráfica y se formaron en ambientes sedimentarios diferentes, como son: (i) depósitos de desbordamiento y depósitos canalizados (secuencia II) y (ii) llanura fluvial de tipo trenzado (secuencia IV). El estudio petrológico ha revelado que existen diferencias entre ellos en cuanto a la composición modal del esqueleto, la textura sedimentaria y los procesos diagenéticos ocurridos. La señal composicional revela una disminución del contenido en plagioclasa, que se corresponde con un aumento del contenido en fragmentos de rocas, así como una disminución en la compactación y grado de cementación de la secuencia II a la IV. La tipología y cronología de los cementos indica una profundidad de enterramiento coherente con una etapa mesodiagenética temp The Triassic Red Beds of the Tabular Cover of the Iberian Meseta consist on fluvial sandstone bodies embedded in overbank fines. The studied deposits correspond to two of the four sequences of the stratigraphic succession and developed under different sedimentary environments as: (i) overbank and channel deposits (sequence II) and (ii) braidplain deposits (sequence IV). The petrological study has revealed the main differences between them as a function of framework composition, textural parameters and diagenetic processes. Compositional trends highlighted a decrease of plagioclase content to which correspond major content in rock fragments, as well as a minor compaction and degree of cementation from sequence II to IV. Cements types and chronology suggest a depth of burial according to an early meso-diagenesis stage

Uno studio monografico sulle antiche varietà di pero dell’Emilia-Romagna può sembrare un’opera fuori tempo, magari inutile, o sembrare la riproposizione di un catalogo descrittivo, già appartenuto alla letteratura specialistica del passato e perciò consegnato alle biblioteche storiche. Ma non è così, per una serie di ragioni. Fra queste ci sarà certamente il desiderio di ritornare alle abitudini e ai sapori del passato, ormai scomparsi dalle nostre tavole, alimentate come sono dalle pere del presente, che seguono unicamente logiche mercantili. Ma nell’attuale ricerca di nuovi indirizzi agricoli volti a modificare la frutticoltura intensiva, verso principi corrispondenti ad una sostenibilità ecologica ambientale e salutistica, il recupero di un patrimonio genetico del passato, in parte consolidato da secoli di coltura, richiede conoscenze e valutazioni dirette.

La coltivazione del pero in Emilia-Romagna ha una lunga storia che nasce dalla vocazionalità regionale per questa coltura. Questo stretto rapporto ha permesso lo sviluppo di un ricco germoplasma locale. La riscoperta delle antiche varietà di germoplasma non deve essere vista solo in riferimento al loro indubbio valore culturale, legato agli usi e alle tradizioni delle popolazioni che hanno coltivato queste antiche varietà. Bisogna ricordare che l’importanza delle cultivar locali risiede anche nell’elevata variabilità genetica che le caratterizza e ha permesso loro di adattarsi alle specifiche condizioni ambientali presenti in regione. Pur essendo spesso prive delle caratteristiche qualitative delle moderne pere che dominano i mercati, queste antiche varietà di pero dell’Emilia-Romagna meritano di essere preservate dall’erosione genetica anche per i caratteri che possono essere reintrodotti nei programmi di miglioramento genetico quali, ad esempio, la precocità di raccolta, la serbevolezza, la polpa rossa del frutto, la resilienza a stress ambientali in anni caratterizzati da profondi mutamenti climatici.

The eastern Adriatic coast of Croatia is characterized by an extremely indented hard rock coastline made up predominantly of carbonate rocks. However, where sufficient amounts of clastic material are available sandy pocket beaches occur. These beaches represent a delicate coastal environment, one which is easily subject to destructive processes if imbalance is created between the supply of detritus and erosion. Studies have shown that considerable variability in composition may exist among closely spaced beaches (e.g. Lužar-Oberiter et al., 2008), advocating the necessity of a localized approach when considering management issues such as beach nourishment. We have compiled previously published and new unpublished quantitative heavy mineral data from beach sands and potential source rocks along the Croatian coast. In order to demonstrate the variability in beach sand composition, identify and explain regional similarities and link beach material to source rocks, hierarchical cluster analysis was applied on the compositional variables after having transformed them using a logistic transformation (Hartigan, 1975). The number of clusters was determined using Pseudo-t2 statistic and cubic clustering criterion (Milligan & Cooper, 1985). Profiling of the clusters and identification of key heavy minerals is facilitated by a decision tree. Analysis was performed using SAS v9.2 and JMP v8 software. The derived clusters distinctly mirror geographic regions along the coast from which the samples come from. In many cases there is a close relation between beaches and rocks in the nearby hinterland, making it possible to identify specific source rocks supplying individual beaches, but also raises questions on mixing of material from more than one source. The quantitative tools offer a better understanding of how beaches are supplied with sandy material along the Croatian coast, which is essential if their aesthetic, recreational and economic values are to be preserved. It is our future goal to further build and expand the database of Croatia’s beach environments to include and integrate other quantitative data regarding composition, grain size, as well as relevant environmental data. Information derived from such a database should benefit planning of sustainable development along the Croatian coastline. Hartigan JA (1975) Clustering Algorithms. John Wiley & Sons, New York. Lužar-Oberiter B, Mikulčić Pavlaković S, Crnjaković M and Babić Lj (2008) Variable sources of beach sands of north Adriatic islands: examples from Rab and Susak. Geologia Croatica 61, 379-384. Milligan GW and Cooper MC (1985) An Examination of Procedures for Determining the Number of Clusters in a Data Set. Psychometrika 50, 159–179.