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The lawsonite-glaucophane blueschists of Elba Island (Italy)
Evidence for high-P blueschist-facies metamorphism was found in metabasites embedded in calcschists of Eastern Elba Island (Northern Apennines, Italy). Study of immobile trace elements (REEs and HFSEs) in the metabasites indicates an affinity with T- and E-MORBs, and they are interpreted as sill or dykes intruded in the western margin of the Adria continental plate. The minerals are heterogeneously distributed in the rock, constituting mafic and Ca-Al-rich microdomains inherited respectively from the magmatic pyroxene- and plagioclase-rich zones of the original doleritic rock. The peak pressure paragenesis consisted of lawsonite, aegirine-omphacite, glaucophane and chlorite. Former rhombic prism of lawsonite has been replaced by pseudomorphic clinozoisite (0.1 mm in size) with inclusions of Ms. ± Ab ± Qz. The inclusions are preferentially oriented parallel to one of the diagonals of the basal rhombic sections, indicating that the two diagonals were not crystallographically equivalent. This implies that the protocrystals were orthorhombic prisms with {110} faces, which is the case of lawsonite. The different compositions shown by white mica and epidote in the pseudomorphs (muscovite and Fe3+-poor clinozoisite) and in the matrix (phengite and Fe,sup>3+-rich epidote) also suggest the former presence of Mg- and Fe-poor lawsonite in these rocks. Thermodynamic modelling, using the THERMOCALC software and dataset, suggests that metabasites experienced a clockwise P-T path from the lawsonite-blueschist to epidote-blueschist subfacies, down to greenschist facies. The estimated peak pressure conditions are P ≥ 1.6 GPa and 450 40Ar/39Ar method. This evolution is interpreted in terms: (i) intrusion of basic magmas in carbonatic and pelitic sediments (post-late Cretaceous, pre-Oligocene), (ii) subduction (Oligocene), (iii) collision (early Miocene: 19.8 ± 1.4 Ma), (iv) exhumation and granite intrusion (middle-late Miocene), favored by extensional tectonics. We underline that the eastern part of Elba Island belongs to a blueschist-facies belt that extends from Gorgona Island, in the northwest, to Argentario and Giglio Island in the southeast, so many of the conclusions of this study can be extended to the whole of this belt
HP-LT metamorphism in Elba Island: Implications for the geodynamic evolution of the inner Northern Apennines (Italy)
The inner Northern Apennines belt (i.e., northern Tyrrhenian Sea and Tuscany) is an Alpine chain affectedby high-P metamorphic conditions during its evolution. Although Elba Island is structurally located closeto the Adria-Europe suture zone, for several authors it represents a sector of the orogen affected bylow-P metamorphism. The involvement of Elba Island tectonic units in high-P metamorphism was onlysuspected for the sparse presence of phengitic white mica in the metasedimentary rocks. This paperpresents the first clear evidence of high-P and low-T metamorphism found in metabasite rocks embed-ded in the Cretaceous calcschist of eastern Elba Island. Mineral composition of metabasite includesGln + Cpx + Ep + Ab + Act + Qtz + Ilm ± Ti-oxide ± Spn and is indicative of a former equilibration in the epi-dote blueschist subfacies and subsequent retrogression in the greenschist facies. Recorded metamorphicconditions are P = 0.9–1.0 GPa and T = 330–350◦C. Tectonic discrimination using immobile elements inthe metabasite does not point to an oceanic setting. As a consequence, the metasedimentary succes-sion containing metabasite is explained as belonging to the Tuscan continental domain and not to theLigurian-Piedmont Ocean, as previously interpreted. Our results have two significant implications: (i)it is confirmed and strengthened that the tectonic stacking of the Elba Island units did not occur in alow-pressure context; (ii) Elba Island is now completely reconciled in the tectonic and metamorphicevolution of the inner Northern Apennines
Assessment of fibrinolytic activity by measuring the lysis time of a tissue-factor-induced clot: a feasibility evaluation.
A clot lysis time assay in which a tissue factor—induced fibrin clot is lysed by exogenously added tissue plasminogen activator has been recently reported. We evaluated the feasibility of clot lysis time in a routine hemostasis laboratory, and its correlation with thrombin activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 levels and changes with aging in 185 healthy participants. Clot lysis time was assessed by monitoring changes in turbidity during clot formation and subsequent lysis using a computerized kinetic spectrophotometric microtiter plate. After preliminary experiments, 100 and 160 ng/mL tissue plasminogen activator concentrations were chosen for the study. Clot lysis time was calculated by a new mathematical analysis of the lysis curve based on discrete derivative. Clot lysis time, thrombin activatable fibrinolysis inhibitor, and plasminogen activator inhibitor-1 plasma levels showed a normal distribution. For both concentrations of tissue plasminogen activator, clot lysis time progressively increased with increase in age (P < .0001) and was significantly correlated with thrombin activatable fibrinolysis inhibitor antigen, thrombin activatable fibrinolysis inhibitor activity, and plasminogen activator inhibitor-1 antigen (at least P < .01). During linear regression analysis, thrombin activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 antigen were found to significantly influence clot lysis time (at least P < .01). Clot lysis time determination has a good laboratory performance. Our new method of calculation is independent of the time of reading and allows a more accurate and consistent detection of both short and prolonged lysis times. Our data suggest the feasibility of the use of this test in the work of routine hemostasis laboratory
La disclosure volontaria del modello di business nel prospetto informativo di quotazione: un’analisi comparative
How do companies to be listed actually deal with voluntary disclosure of their business model? Is it true that firms with greater knowledge-based resources and technological innovation endowments have a lower propensity to adopt fully open communication behaviors? This paper aims to identify the voluntary disclosure policies adopted by three Italian companies in their Initial Public Offering (IPO) prospectuses in order to investigate whether any differences may depend on the type of innovation underlying each business model. A series of interviews conducted with the top management made it possible to understand more deeply the business model of each company. Further, a content analysis has been developed to compute a measure of disclosure and to point out the strategic concepts and their relevance. We provide evidence that companies with a business model based on technology-push innovation have a lower propensity to the full disclosure of their intangible components, particularly of those mainly based on knowledge as these are also invisible. Our study adds to the literature of business and financial reporting by focusing on a new object of inquiry, that is the business model. The business model plays an important role in allowing external actors to understand a company’s value, thus companies’ strategic communication should be shaped accordingly. The results suggest the need to address the issue of voluntary disclosure of the business model by first distinguishing “visible” intangible resources from those that are “invisible” (both to financial and competitive markets). The study aims to make a contribution to the ongoing debate on business and financial reporting practice
Major prospects for exploring canine vector borne diseases and novel intervention methods using 'omic technologies
Canine vector-borne diseases (CVBDs) are of major socioeconomic importance worldwide. Although many studies have provided insights into CVBDs, there has been limited exploration of fundamental molecular aspects of most pathogens, their vectors, pathogen-host relationships and disease and drug resistance using advanced, 'omic technologies. The aim of the present article is to take a prospective view of the impact that next-generation, 'omics technologies could have, with an emphasis on describing the principles of transcriptomic/genomic sequencing as well as bioinformatic technologies and their implications in both fundamental and applied areas of CVBD research. Tackling key biological questions employing these technologies will provide a 'systems biology' context and could lead to radically new intervention and management strategies against CVBDs
Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field
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