Amphiboles and clinopyroxenes from Euganean (NE Italy) cumulus enclaves: evidence for subduction related melts below Adria microplate

Euganean Hills are a magmatic district belonging to the Veneto Volcanic Province, whose magmatism developed during an extensional tectonic regime within the Alpine orogenesis in an intra-plate setting (the Adria microplate). Mafic and ultramafic cumulus occur within the Euganean trachytes. We estimated the trace element composition of liquids in equilibrium with cumulus amphiboles and clinopyroxenes, employing a set of partition coefficients. Primary melt compositions were back-calculated assuming an earlier fractional crystallization of olivine and clinopyroxene. These melts are characterized by a marked enrichment in LILE, Th and U relative to N-MORB. Conversely, HREE and HFSE concentrations resemble N-MORB contents. These geochemical signatures are typical of subduction-related magmas, which also characterized the parental melts of Adamello cumulates. Conversely, Veneto Volcanic Province mafic lavas show geochemical patterns typical of anorogenic magmas. Therefore, those rocks are not cogenetic with mafic cumulates, as these rocks are interpreted as crystallized from Alpine subduction-related basaltic magmas, which were subsequently dismembered and transported to shallower levels by ascending lavas related to the Veneto Volcanic Province magmatism. Therefore, magmatic products related to Alpine subduction are, more widespread beneath the Adria microplate than previously known

Geochemistry and zircon U-Pb geochronology of magmatic enclaves in trachytes from the Euganean Hills (NE Italy): Further constraints on Oligocene magmatism in the eastern Southern Alps

This study presents the results of the geochemical and geochronological investigation of magmatic enclaves in trachytes from the Euganean Hills (NE Italy). The Euganean Hills magmatic district is the most recent (Eocene-Oligocene) volcanic distric within the Veneto Volcanic Province (VVP), which represents the main magmatic event in the eastern Southern Alps. The studied enclaves include intrusive and crystal mush types, the latter characterised by embayments of the host trachyte towards the core of the enclaves. Both types have zircon U-Pb ages of ∼30-32 Ma, indicating that they are contemporaneous with the second Euganean magmatic phase. Amphibole-bearing intrusive enclaves (syenites and quartzo-monzonites) and crystal mushes have similar major and trace element compositions (e.g. REE, Rb, Ba, K, Nb, Pb, Th and Y contents) as those of the host trachyte. They are interpreted as magma chamber solidification fronts with different degrees of crystallization, which were caught as enclaves by the trachytic magma during its ascent. Amphibole-free intrusive enclaves show peculiar trace element compositions (depletion in Th, U, Nb, Ta, MREE and HREE, and marked Eu positive anomaly), in contrast to the compositions of Euganean lavas and other studied enclaves, and are interpreted as cumulative rocks resulting from concentration of crystals fractionated during trachyte-rhyolite evolution. This study confirms that low-pressure fractional crystallisation played a primary role in the evolution of magma in the VVP. The first zircon U-Pb ages from the Euganean rocks prove a Lower Oligocene age for the second Euganean magmatic phase. The use of this robust chronometer should be extended to the Euganean lavas, to better constrain the chronological sequence of eruptive events

Drug targets in Leishmania

Leishmaniasis is a major public health problem and till date there are no effective vaccines available. The control strategy relies solely on chemotherapy of the infected people. However, the present repertoire of drugs is limited and increasing resistance towards them has posed a major concern. The first step in drug discovery is to identify a suitable drug target. The genome sequences of Leishmania major and Leishmania infantum has revealed immense amount of information and has given the opportunity to identify novel drug targets that are unique to these parasites. Utilization of this information in order to come up with a candidate drug molecule requires combining all the technology and using a multi-disciplinary approach, right from characterizing the target protein to high throughput screening of compounds. Leishmania belonging to the order kinetoplastidae emerges from the ancient eukaryotic lineages. They are quite diverse from their mammalian hosts and there are several cellular processes that we are getting to know of, which exist distinctly in these parasites. In this review, we discuss some of the metabolic pathways that are essential and could be used as potential drug targets in Leishmania