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There are still open questions about the deep structure beneath the Western Alps. Seismic velocity tomographies show the European slab subducting beneath the Adria plate, but all these images did not clarify completely the possible presence of tears, slab windows, or detachments. Seismic anisotropy, considered an indicator of mantle deformation and studied using data recorded by dense networks, allows a better understanding of mantle flows in terms of location and orientation at depth. Using the large amount of shear wave-splitting and splitting-intensity measurements available in the Western Alps, collected through the CIFALPS2 temporary seismic network, together with already available data, some new patterns can be highlighted, and gaps left by previous studies can be filled. Instead of the typical seismic anisotropy pattern parallel to the entire arc of the Western Alps, this study supports the presence of a differential contribution along the belt that is only partly related to the European slab steepening. A nearly north-south anisotropy pattern beneath the external Western Alps, a direction that cuts the morphological features of the belt, is clearly found with the new CIFALPS2 measurements. It is, however, confirmed that the asthenospheric flow from central France towards the Tyrrhenian Sea is turning around the southern tip of the European slab.

Cenozoic uplift in the Tianshan played an important role in driving Proto-Paratethys Sea retreat and Asian aridification. However, most paleoclimate studies have focused on the Pamir-Tianshan corridor, and frequently overlook the role of the entire Tianshan range in modifying the Central Asian climate during Cenozoic uplift. When and how Cenozoic deformation of Tianshan was initiated and propagated are intensively debated which makes its role in contributing to climate change in Central Asia more ambiguous. To address this issue, this study presents new detrital zircon U-Pb and detrital apatite U-Pb and fission track age data from Cenozoic sedimentary successions (54-0 Ma) in the northern margin of the Tarim Basin and integrates these data with published provenance data from adjacent regions. Our results show that deformation/uplift of the Baicheng-Kuqa Depression and the South Tianshan occurred at similar to 41-37 Ma and similar to 24 Ma, when topographic growth of South Tianshan began to block the flow of sediment from the north. Continued uplift of the South Tianshan completely blocked fluvial transport from the Central Tianshan-Yili Block by similar to 10 Ma, as shown by the paucity of 380-310 Ma detrital zircons/apatites. Far-field, north-directed compressive stress resulting from the India-Asia collision began to propagate toward the South Tianshan and its foreland during the Late Eocene, and continued to propagate into the South Tianshan and northward at the similar to 24 Ma and 10 Ma. Finally, we suggest a two-stage of aridification in the Tarim Basin which can be linked to two stages (similar to 24 and 10 Ma) of growth of the Tianshan.

La tesi esplora le correlazioni fra composizione chimica del particolato emesso in frenata e alcuni fattori quali: i) le combinazioni di materiali che compongono l'interfaccia tribologica; ii) le condizioni di guida; iii) le frazioni dimensionali in cui vengono prodotti i particolati, This thesis reports on the correlations between the compositional features of the particulates produced by brakes and several determining or modulating factors, such as: i) The starting material composing the friction couple; ii) the driving conditions; and iii) the dimensional fractions in which the particulates are generated and emitted.

I vaccini hanno rappresentato una svolta nella medicina. Dalla loro introduzione da parte di jenner nel 1798, i vaccini hanno abbassato drammaticamente il tasso di mortalità, esteso l’aspettativa di vita media e ridotto l’incidenza di malattie come tetano, polio, morbillo e altre, ed hanno portato all’eradicazione del vaiolo. Dopo secoli di miglioramenti, i vaccini si sono evoluti: dai vaccini attenuati, molto efficaci ma non troppo sicuri in quanto usavano patogeni vivi, fino ai moderni vaccini a sottounità od ad acidi nucleici. Questi ultimi sono molto più sicuri dei vaccini attenuati, poiché la possibilità di effetti collaterali è estremamente più bassa, ma senza una formulazione adeguata sono anche meno efficienti nel portare ad una buona memoria immunologica, poiché mancano delle proprietà immunostimolatorie di un patogeno intero. In effetti, i vaccini moderni contengono molti meno antigeni che in passato, pertanto, per arrivare ad un buon tasso di efficaca, è necessaria la presenza di adiuvanti nella loro formulazione. Gli adiuvanti vaccinali sono composti chimici o biologici che inducano una risposta immunitaria tale da migliorare la capacità di un antigene di generare una buona memoria immunologica, così da accrescere l’efficacia di un vaccino mantenendo un basso rischio. Per decenni, l’unico adiuvante vaccinale approvato per l’uso umano è stato l’Alum, una miscela di alluminio idrossido ed alluminio fosfato. Negli ultimi anni, tuttavia, c’è stato un maggiore interesse in questo ambito, che ha portato all’approvazione di un certo numero di adiuvanti, fra cui l’MPLA, un agonista del Toll-Like Receptor 4 (TLR4). Il TLR4 è una proteina fondamentale nel processo dell’immunità innata: è il sensore umano della presenza batterica, grazie alla sua abilità di legare il lipopolisaccaride (LPS), un componente fondamentale della membrana batterica esterna. Dopo il legame, il TLR4 dimerizza, provocando una cascata di chinasi intracellulare che a sua vol, Vaccines have been a breakthrough in medicine. Since their introduction in 1798 by Jenner, vaccines dramatically lowered mortality rate, extended average life expectancy and reduced incidence of severe diseases such as tetanus, polio, measles and others, while totally eradicating smallpox. After centuries of improvements, vaccines evolved: from attenuated live vaccines, having high efficacy rate but low safety profile as they used alive pathogens, to modern subunit or nucleic acid vaccines. The latter are much safer than attenuated vaccines, as the possibility of adverse events is extremely lower, but without the proper formulation they’re also less efficient in eliciting a good immune memory, as they lack the immunostimulatory properties of a whole pathogen cell. Indeed, modern vaccines contains far less antigens than in the past, therefore, to reach high efficacy rates, the presence of adjuvants is required in vaccine formulation. Vaccine adjuvants are chemical or biological compounds able to induce a proper immune response which enhances antigens ability to generate a good immune memory, so they can rise the overall efficiency of a vaccine, while maintaining a low risk profile. For decades, the only vaccine adjuvant approved for human use has been Alum, a mixed salt formed by aluminium hydroxide and aluminium phosphate In recent decades, however, increased interest on this topic brought to approval of a handful of adjuvants such MPLA, a Toll-Like Receptor 4 (TLR4) agonist. TLR4 is a pivotal protein in innate immunity: it is the human sensor for bacterial presence, due to its ability to bind lipopolysaccharide (LPS), a fundamental component of bacterial outer membrane. Upon binding, TLR4 dimerizes, triggering an intracellular kinase cascade which kickstarts the inflammatory process through the release of cytokines. These cytokines also help shaping the adaptive immune response, directing it toward a Th1 or Th2 response and priming memory B cells. For its centralit

The assessment of seismic activity in the shallow continental mantle has long been hindered by the low resolution of both seismic imaging and earthquake locations in young collision zones. Here, we combine the most recent and high-resolution image of the lithospheric structure of the Western Alps with a high quality dataset of anomalously deep earthquakes recorded in the same area in the past 25 yrs. We show that these earthquakes are aligned on an active lithospheric strike-slip fault, and we provide evidence that this fault is located in the mantle wedge beneath the Adriatic Moho. Our results: (i) provide direct evidence that deep material can be seismogenic or not depending on the lithology; (ii) confirm the role of serpentinization in favoring the aseismic creep of mantle rocks; and (iii) demonstrate that the upper mantle can be stiff and seismogenic not only in cold cratons, but also in young orogenic belts.

The question of lateral and/or vertical continuity of subducted slabs in active orogens is a hot topic partly due to poorly resolved tomographic data. The complex slab structure beneath the Alpine region is only partly resolved by available geophysical data, leaving many geological and geodynamical issues widely open. Based upon a finite-frequency kernel method, we present a new high-resolution tomography model using P wave data from 527 broadband seismic stations, both from permanent networks and temporary experiments. This model provides an improved image of the slab structure in the Alpine region and fundamental pinpoints for the analysis of Cenozoic magmatism, (U)HP metamorphism, and Alpine topography. Our results document the lateral continuity of the European slab from the Western Alps to the central Alps, and the downdip slab continuity beneath the central Alps, ruling out the hypothesis of slab break off to explain Cenozoic Alpine magmatism. A low-velocity anomaly is observed in the upper mantle beneath the core of the Western Alps, pointing to dynamic topography effects. A NE dipping Adriatic slab, consistent with Dinaric subduction, is possibly observed beneath the Eastern Alps, whereas the laterally continuous Adriatic slab of the Northern Apennines shows major gaps at the boundary with the Southern Apennines and becomes near vertical in the Alps-Apennines transition zone. Tear faults accommodating opposite-dipping subductions during Alpine convergence may represent reactivated lithospheric faults inherited from Tethyan extension. Our results suggest that the interpretations of previous tomography results that include successive slab break offs along the Alpine-Zagros-Himalaya orogenic belt might be proficiently reconsidered.

We analyze the source-to-sink variations of in situ 10Be, 26Al and 21Ne concentrations in modern sediment of the Po river catchment, from Alpine, Apennine, floodplain, and delta samples, in order to investigate how the cosmogenic record of orogenic erosion is transmitted across a fast-subsiding foreland basin. The in situ 10Be concentrations in the analyzed samples range from ∼0.8×104 at/gQTZ to ∼6.5×104 at/gQTZ. The 10Be-derived denudation rates range from 0.1 to 1.5 mm/yr in the Alpine source areas and from 0.3 to 0.5 mm/yr in the Apenninic source areas. The highest 10Be-derived denudation rates are found in the western Central Alps (1.5 mm/yr). From these data, we constrain a sediment flux leaving the Alpine and the Apenninic source areas (>27 Mt/yr and ca. 5 Mt/yr, respectively) that is notably higher than the estimates of sediment export provided by gauging (∼10 Mt/yr at the Po delta). We observe a high variability in 10Be concentrations and 10Be-derived denudation rates in the source areas. In the Po Plain, little variability is observed, and at the same time, the area-weighed 10Be concentration of (2.29±1.57)×104 at/gQTZ (±1 SD of the dataset) from both the Alps and the Apennines is poorly modified (by tributary input) in sediment of the Po Plain ((2.68±0.78,±1 SD)×104 at/gQTZ). The buffering effect of the Po floodplain largely removes scatter in 10Be signals. We test for several potential perturbations of the cosmogenic nuclide record during source to sink transfer in the Po basin. We find that sediment trapping in deep glacial lakes or behind dams does not significantly change the 10Be-mountain record. For example, similar 10Be concentrations are measured upstream and downstream of the postglacial Lake Maggiore, suggesting that denudation rates prior to lake formation were similar to today's. On the scale of the entire basin, the 10Be concentration of basins with major dams is similar to those without major dams. A potential modi

The Adriatic microplate is a key player in the Western Mediterranean tectonic puzzle, but its Oligocene-Miocene dynamics are not yet fully understood. In fact, even though the timing and magnitude of Adriatic slab rollback and backarc extension in the Apennines have long been established, the timing of progressive Adria indentation beneath the Central Alps and major strike-slip motion along the Insubric fault are still poorly constrained. Here we tackle these issues by utilizing detrital zircon U-Pb geochronology on Adriatic foredeep turbidites, i.e., by comparing the geochronologic fingerprints of the exhuming tectonic domes of the Central Alps (Ticino and Toce subdomes) with those of the Oligocene-Miocene turbidites chiefly derived from their erosion. We analyzed 11 sandstone samples ranging in age from 32 to 18 Ma. The ratio between Variscan and Caledonian zircon grains (which are dominant in the Toce and Ticino subdomes, respectively) sharply increases at ca. 24-23 Ma. This major provenance change marks the westward shift of the Adriatic indenter beneath the Central Alps and the associated right-lateral activity of the Insubric fault. The coexistence of strike-slip motion at the northern boundary of the Adriatic microplate at ca. 24-23 Ma and trench retreat during scissor-type backarc opening to the west requires a near-vertical rotation axis located at the northern tip of the Ligurian-Provençal basin. We propose that the rotation axis position was controlled by the interaction between the European and the Adriatic slabs, which may have collided at depth by the end of the Oligocene, triggering the westward shift of the Adriatic indenter beneath the Central Alps.

A new multi-thermochronological dataset from Corsica-Sardinia is here employed to constrain the Meso-Cenozoic evolution of the Western Mediterranean area and the problematic transition in space and time between the opposite-dipping Alpine (European) and Apenninic (Adriatic) subductions. The dataset, including zircon and apatite fission track and apatite (U-Th)/He data, covers the whole Meso-Cenozoic time interval, and fits the theoretical age pattern that is expected in distal passive margins after continental break-up. This demonstrates that Corsica-Sardinia represents a fragment of the northern Tethyan margin still preserving the thermochronological fingerprint acquired during Middle Jurassic rifting. Mesozoic apatite (U-Th)/He ages from crustal sections located close to the Tethyan rift axis (i.e., central and eastern Sardinia) show that no European continental subduction took place south of Corsica since the Mesozoic. Along the Sardinia transect, post-Jurassic Adria-Europe convergence was possibly accommodated by Adriatic subduction, consistent with the onset of orogenic magmatism. In middle Eocene-Oligocene times, the northward translation of the Adriatic slab beneath the former Tethyan margin induced a coeval northward migration of erosional pulses at the surface, constrained by a trend of progressively decreasing fission track ages from southern Sardinia to NW Corsica. The Adriatic slab reached the Alpine wedge of Corsica by the end of the Oligocene without any breakoff of the European slab, and started retreating in Neogene times triggering the long-recognized basin opening in the backarc region.

Detrital geochronology studies require a careful quantification of hydraulic sorting effects and of the variable abundance (fertility) of datable minerals in different parent rocks. Because the physical processes of settling and selective entrainment are well known, their effects in sediments can be easily detected and modeled mathematically. By contrast, mineral fertility in parent rocks depends on their full geological history. As a consequence, the relationships between bedrock geology and mineral fertility are hardly predictable, and a direct measurement of this latter parameter is thus required. In this review article, we describe the basic principles of hydraulic sorting, and illustrate a quantitative approach for mineral fertility determination that applies these basic principles to the analysis of modern sediments. Its application to the European Alps shows that apatite and zircon fertility values may range over three orders of magnitude. Variable mineral fertility in parent rocks thus represents, by far, the largest source of bias in detrital geochronology studies. Our study highlights an evident relationship between bedrock geology and mineral fertility, which confirms that the mineral concentration in modern sediments, in the lack of hydraulic sorting effects, is a good proxy of the mineral abundance in bedrock. Mineral fertility maps of the European Alps unravel that metamorphic and plutonic rocks generally have higher apatite and zircon fertility values than sedimentary rocks, but major variations are also observed between different tectonic units within the same paleogeographic domain. The impact of mineral fertility in detrital studies is eventually illustrated with examples from the Alpine region, based on alternative sampling strategies (i.e., the confluence sampling and the along-trunk sampling approaches). We show that geological interpretations are strongly improved when mineral fertility is properly taken into account, not only in modern setting

Coarse-grained gravity flow deposits are quite common in the stratigraphic record, but their capability in transporting cobbles and boulders at great distance from the eroding sources is still poorly assessed. Here, we tackle this issue by the analysis of coarse-grained gravity flow deposits of the Aveto Formation, deposited in the Early Oligocene Adriatic foredeep and now exposed in the accretionary wedge of the Northern Apennines (Italy). We combine field observations and provenance constraints provided by Laser Ablation Split Stream (LASS)-ICP-MS depth-profiling of detrital zircon grains. We found that the polymodal grain-age distributions in the analyzed samples, dominated by Periadriatic, Variscan and Caledonian age populations, also include Late Cretaceous to Paleocene ages associated to thin epitaxial overgrowths on older zircon cores. These overgrowths display Th/U and REE patterns consistent with a metamorphic origin, and provide a diagnostic fingerprint that indicates the Bergell area in the Central Alps as the only viable source of coarse detritus, including cobbles and boulders of magmatic and metamorphic rocks, transported by gravity flows towards the nascent Adriatic foredeep. Our results provide not only pin-points for a reliable paleotectonic reconstruction of the Bergell-Aveto source-to-sink system, one of the most remarkable features of the Oligocene Adria-Europe plate boundary, but also compelling evidence for ∼300 km axial transport by gravity flows experienced by coarse detritus derived from the Oligocene Central Alps. The eruptions of the Bergell volcanic complex provided abundant pyroclastic material variably mixed with metamorphic detritus, that was quickly funneled into submarine canyons triggering southward-directed gravity flows. Active tectonics, pyroclastic material provided by volcanic eruptions, steep canyons close to the shoreline and the presence of fault-controlled submarine troughs, may effectively promote the long-distance tr

The first discovery of ultrahigh-pressure coesite in the European Alps 30 years ago led to the inference that a positively buoyant continental crust can be subducted to mantle depth; this had been considered impossible since the advent of the plate tectonics concepts. Although continental subduction is now widely accepted, there remains debate because there is little direct (geophysical) evidence of a link between exhumed coesite at the surface and subducted continental crust at depth. Here we provide the first seismic evidence for continental crust at 75 km depth that is clearly connected with the European crust exactly along the transect where coesite was found at the surface. Our data also provide evidence for a thick suture zone with downward-decreasing seismic velocities, demonstrating that the European lower crust underthrusts the Adriatic mantle. These findings, from one of the best-preserved and long-studied ultrahigh-pressure orogens worldwide, shed decisive new light on geodynamic processes along convergent continental margins.

The retrobelts of doubly vergent collisional orogens are classically interpreted as late-stage postcollisional features. Here, we integrate literature data with new structural and thermochronological evidence from the European Alps in order to document the precollisional development of the retrobelt segment exposed in the central southern Alps. During the Late Cretaceous, by inversion of inherited extensional faults of Permian age, the Variscan basement of the central southern Alps was stacked southward onto the Permian-Mesozoic cover sequences of the Adria margin. These thrust systems were first deformed within regional-scale antiforms (the "Orobic anticlines") and then cut by Eocene magmatic bodies. Our apatite fission-track data show that these units were largely structured and exhumed to shallow crustal levels before the intrusion of the Eocene magmatic rocks. Therefore, thrusting and folding in the Alpine retrobelt took place before the final closure of the Alpine Tethys and subsequent continental collision between Adria and Europe. Final exhumation and uplift in the northern part of the Southalpine retrobelt took place under a dextral transpressional regime largely coeval with the right-lateral strike-slip activity along the Insubric fault. In Neogene times, deformation propagated southward, leading to the formation of a frontal thrust belt that is largely buried beneath the Po Plain.

The anomalously deep seismicity beneath the Western Po Plain is here analyzed to shed light on the complex and still poorly understood tectonic configuration of the internal side of the Western Alps area. The original dataset, including 590 earthquakes deeper than 20. km recorded during the last 25. years, has been accurately relocated with HypoDD using both catalog and cross-correlation differential times. We found that the distribution of seismic events faithfully mirrors the presence of two distinct tectonic domains (axial belt domains 1 and 2), originally belonging to the Paleogene Alpine wedge and now anomalously juxtaposed beneath the sedimentary infill of the Western Po Plain. Shallow, low-magnitude earthquakes (<. 20. km depth) are concentrated in domain 1, and are possibly triggered by the isostatic reequilibration of the accretionary wedge. Earthquakes between 25 and 75. km depth, instead, define a NNW-SSE linear cluster along the boundary between domains 1 and 2, and mark an apparent plane steeply dipping to the ENE. We propose that this plane may represent a major tectonic boundary of Neogene age, here referred to as the Rivoli-Marene deep fault. Focal mechanisms along the Rivoli-Marene deep fault are invariably transpressional, and suggest ongoing left-lateral motion in agreement with available plate motion constraints. The normal throw inferred from surface geology data (>. 8. km), and accommodated in correspondence of the fault, could be linked to its Neogene activity, coeval with the northward translation of the retreating Adriatic slab.

Since the first discovery of ultrahigh pressure (UHP) rocks 30 years ago in the Western Alps, the mechanisms for exhumation of (U)HP terranes worldwide are still debated. In the western Mediterranean, the presently accepted model of synconvergent exhumation (e.g., the channel-flow model) is in conflict with parts of the geologic record. We synthesize regional geologic data and present alternative exhumation mechanisms that consider the role of divergence within subduction zones. These mechanisms, i.e., (i) the motion of the upper plate away from the trench and (ii) the rollback of the lower plate, are discussed in detail with particular reference to the Cenozoic Adria-Europe plate boundary, and along three different transects (Western Alps, Calabria-Sardinia, and Corsica-Northern Apennines). In the Western Alps, (U)HP rocks were exhumed from the greatest depth at the rear of the accretionary wedge during motion of the upper plate away from the trench. Exhumation was extremely fast, and associated with very low geothermal gradients. In Calabria, HP rocks were exhumed from shallower depths and at lower rates during rollback of the Adriatic plate, with repeated exhumation pulses progressively younging toward the foreland. Both mechanisms were active to create boundary divergence along the Corsica-Northern Apennines transect, where European southeastward subduction was progressively replaced along strike by Adriatic northwestward subduction. The tectonic scenario depicted for the Western Alps trench during Eocene exhumation of (U)HP rocks correlates well with present-day eastern Papua New Guinea, which is presented as a modern analog of the Paleogene Adria-Europe plate boundary.

Garnet is one of the most widespread heavy minerals in sediments derived from orogenic systems. Its chemical composition varies systematically with temperature and pressure conditions, and thus provides information on the metamorphic evolution of source areas that is crucial in tectonic and geodynamic reconstructions. Garnet is easily identified in mineral grain mounts and is relatively stable during burial diagenesis. Raman spectroscopy allows rapid determination of garnet compositions in grain mounts or thin sections of sand and sandstone samples, and can be used to assess their density and chemical composition quite accurately (“MIRAGEM” method of Bersani et al., 2009; Andò et al., 2009). In the D’Entrecastreaux Islands of southeastern Papua New Guinea, the world’s youngest (U)HP rocks are exposed. There, mafic rocks and their felsic host gneisses were metamorphosed under eclogite facies conditions from late Miocene to Pliocene, before being exhumed from depths of 90 km (Baldwin et al., 2004, 2008). The eclogite preserves a peak assemblage of garnet, omphacite, rutile, phengite and Si02 (Hill and Baldwin, 1993). A coesite-eclogite has been found in one small island outcrop. In order to sample garnet populations representative of a larger geographical area, we sampled and studied a heavy-mineral-dominated placer sand (HMC 80) from a beach from SE Goodenough Island. Garnet grains in beach sand are associated with blue-green to subordinately green-brown amphibole and minor epidote, omphacitic clinopyroxene, titanite, apatite and rutile. The subordinate low-density fraction is feldspatho-quartzose with high-rank metamorphic rock fragments and biotite (Q62 F35 Lm2; MI 360). Detrital garnets are mostly classified as almandine with relatively high Mg and Ca and lacking Mn, typical of the eclogite facies (Win et al., 2007; type Ci garnets of Mange and Morton 2007; Andò et al., 2013). In well-described stratigraphic sequences within syn-and post-tectonic basins adjacent

The central Southern Alps retrobelt was built trough a polyphase tectonic evolution that developed since the pre-collisional stage in the hangingwall of the E-SE directed Alpine Tethys subduction. Two main pre-Late Eocene deformation phases have been recognized. The first phase (D3a) of Late Cretaceous age was characterized by southward thrusting and large scale folding involving both the Variscan basement and the Permo-Mesozoic cover. A second major deformation phase (D3b) was responsible, during the Early-Middle Eocene, for the growth and southward propagation of the basementcored Orobic Anticlines. The successive compressional phase (D4) occurred after the Adamello intrusion and promoted the development of the foreland belt. In the internal sector of the cSA the D4 deformation resulted in a dextral transpressional to strike-slip reactivation of the Orobic-Porcile-Gallinera thrust system, likely linked to the Oligocene activity along the Insubric Line. Apatite fission track data point out that the present-day exposed cSA retrobelt was already structured and largely exhumed prior of the Adamello intrusion. They also show a post-Oligocene differential exhumation within the cSA belt, with exhumation increasing northward. We suggest that the northward younging direction of exhumation was caused by the progressive indentation of the Adria lithospheric wedge beneath the cSA belt. Transpressive activity along the Insubric Line and major thrust surfaces bounding the northern cSA units, allowed the differential uplifting of the northern sector of the belt.