457 research outputs found

    Late-stage tectonic evolution of the Al-Hajar Mountains, Oman: New constraints from Palaeogene sedimentary units and low-temperature thermochronometry

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    Mountain building in the Al-Hajar Mountains (NE Oman) occurred during two major shortening stages, related to the convergence between Africa-Arabia and Eurasia, separated by nearly 30 Ma of tectonic quiescence. Most of the shortening was accommodated during the Late Cretaceous, when northward subduction of the Neo-Tethys Ocean was followed by the ophiolites obduction on top of the former Mesozoic margin. This shortening event lasted until the latest Santonian - early Campanian. Maastrichtian to Eocene carbonates unconformably overlie the eroded nappes and seal the Cretaceous foredeep. These neo-autochthonous post-nappe sedimentary rocks were deformed, along with the underlying Cretaceous tectonic pile, during the second shortening event, itself including two main exhumation stages. In this study we combine remotely sensed structural data, seismic interpretation, field-based structural investigations and apatite (U-Th)/He (AHe) cooling ages to obtain new insights into the Cenozoic deformation stage. Seismic interpretation indicates the occurrence of a late Eocene flexural basin, later deformed by an Oligocene thrusting event, during which the post-nappe succession and the underlying Cretaceous nappes of the internal foredeep were uplifted. This stage was followed by folding of the post-nappe succession during the Miocene. AHe data from detrital siliciclastic deposits in the frontal area of the mountain chain provide cooling ages spanning from 17.3 to 42 Ma, consistent with available data for the structural culminations of Oman. Our work points out how renewal of flexural subsidence in the foredeep and uplift of the mountain belt were coeval processes, followed by layer-parallel shortening preceding final fold amplification

    Transverse jointing in foreland fold-and-thrust belts: a remote sensing analysis in the eastern Pyrenees

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    Joint systems in the eastern portion of the Ebro Basin of the eastern Pyrenees enjoy near continuous exposure from the frontal portion of the belt up to the external portion of its associated foredeep. Utilizing orthophoto mosaics of these world-class exposures, we have manually digitized over 30 000 joints within a 16 km×50 km study area. The mapped traces exhibit orientations that are dominantly perpendicular to the trend of the belt (transverse) and, subordinately, parallel to the belt (longitudinal). In particular, joints systematically orient perpendicular to the trend of the belt both in the frontal folds and in the inner and central portion of the foredeep basin. Longitudinal joints occur rarely with a disordered spatial distribution, exhibiting null difference in abundance between the belt and the foredeep. Joint orientations in the external portion of the foredeep become less clustered, with adjacent areas dominated by either transverse or oblique joints. Our data indicate that joints in the studied area formed in the foredeep in response to a foredeep-parallel stretching, which becomes progressively less intense within the external portion of the foredeep. There, the minimum stress direction becomes more variable, providing evidence of the poor contribution of the forebulge-perpendicular stretching on stress organization

    Forebulge migration in the foreland basin system of the central-southern Apennine fold-thrust belt (Italy): New high-resolution Sr-isotope dating constraints

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    The Apennines are a retreating collisional belt where the foreland basin system, across large domains, is floored by a subaerial forebulge unconformity developed due to forebulge uplift and erosion. This unconformity is overlain by a diachronous sequence of three lithostratigraphic units made of (a) shallow-water carbonates, (b) hemipelagic marls and shales and (c) siliciclastic turbidites. Typically, the latter two have been interpreted regionally as the onset of syn-orogenic deposition in the foredeep depozone, whereas little attention has been given to the underlying unit. Accordingly, the rate of migration of the central-southern Apennine fold-thrust belt-foreland basin system has been constrained, so far, exclusively considering the age of the hemipelagites and turbidites, which largely post-date the onset of foredeep depozone. In this work, we provide new high-resolution ages obtained by strontium isotope stratigraphy applied to calcitic bivalve shells sampled at the base of the first syn-orogenic deposits overlying the Eocene-Cretaceous pre-orogenic substratum. Integration of our results with published data indicates progressive rejuvenation of the strata sealing the forebulge unconformity towards the outer portions of the fold-thrust belt. In particular, the age of the forebulge unconformity linearly scales with the pre-orogenic position of the analysed sites, pointing to an overall constant migration velocity of the forebulge wave in the last 25 Myr

    Foreign bodies in the upper airways: the experience of two Italian hospitals

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    OBJECTIVE: To study the pattern of foreign bodies in the upper airways as emerging from the hospital records in the Bologna and Siena hospitals in Italy 1997-2002. METHODS: A retrospective review of hospital records was performed using a standardized protocol. All injuries with ICD9 (International Classification of Diseases, 9'h revision) codes ranging from 931 to 934 which occurred in children age 0-14 were considered for the database. RESULTS: One hundred ninety seven patients were included in the database with a diagnosis of Foreign Bodies (FB) over the study period, 78 with ICD931, 105 with ICD932, 12 with ICD933 and 2 with ICD934 discharge diagnosis. Of the 197 patients, 51.90% of the patients were males and the 48.10% were female. Median age was 4 (2, 6). At the moment of the injury, the child was eating (11%), playing (83%) or studying (4%) or cleaning ears (2%). The child was supervised by an adult in doing his/her activities at the moment of injury in the 84.2% of the cases. The child reached the hospital using always private transport (100%), never by using an emergency transport (0%). Most commonly, FB were extracted in ambulatory (95.4%), more rarely using an endoscopic procedure (4.1%), and never using surgery. Hospitalization was required in the 0.5% of cases (1). CONCLUSIONS: Our study showed the substantial epidemiological similarity of the Italian data with the experience of other center in the world. The burden of chocking was very limited in our country, as proven by the limited access to emergency and more invasive procedures. Nevertheless, some consideration can be made from the preventive point of view. Quite surprisingly, the majority of injuries occurred under the supervision of an adult in playing or recreational activities

    Foreign bodies in the upper airways: the experience of two Italian hospitals

    Get PDF
    OBJECTIVE: To study the pattern of foreign bodies in the upper airways as emerging from the hospital records in the Bologna and Siena hospitals in Italy 1997-2002. METHODS: A retrospective review of hospital records was performed using a standardized protocol. All injuries with ICD9 (International Classification of Diseases, 9'h revision) codes ranging from 931 to 934 which occurred in children age 0-14 were considered for the database. RESULTS: One hundred ninety seven patients were included in the database with a diagnosis of Foreign Bodies (FB) over the study period, 78 with ICD931, 105 with ICD932, 12 with ICD933 and 2 with ICD934 discharge diagnosis. Of the 197 patients, 51.90% of the patients were males and the 48.10% were female. Median age was 4 (2, 6). At the moment of the injury, the child was eating (11%), playing (83%) or studying (4%) or cleaning ears (2%). The child was supervised by an adult in doing his/her activities at the moment of injury in the 84.2% of the cases. The child reached the hospital using always private transport (100%), never by using an emergency transport (0%). Most commonly, FB were extracted in ambulatory (95.4%), more rarely using an endoscopic procedure (4.1%), and never using surgery. Hospitalization was required in the 0.5% of cases (1). CONCLUSIONS: Our study showed the substantial epidemiological similarity of the Italian data with the experience of other center in the world. The burden of chocking was very limited in our country, as proven by the limited access to emergency and more invasive procedures. Nevertheless, some consideration can be made from the preventive point of view. Quite surprisingly, the majority of injuries occurred under the supervision of an adult in playing or recreational activities

    Assessment of the immune landscapes of advanced ovarian cancer in an optimized in vivo model

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    BackgroundOvarian cancer (OC) is typically diagnosed late, associated with high rates of metastasis and the onset of ascites during late stage disease. Understanding the tumor microenvironment and how it impacts the efficacy of current treatments, including immunotherapies, needs effective in vivo models that are fully characterized. In particular, understanding the role of immune cells within the tumor and ascitic fluid could provide important insights into why OC fails to respond to immunotherapies. In this work, we comprehensively described the immune cell infiltrates in tumor nodules and the ascitic fluid within an optimized preclinical model of advanced ovarian cancer.MethodsGreen Fluorescent Protein (GFP)-ID8 OC cells were injected intraperitoneally into C57BL/6 mice and the development of advanced stage OC monitored. Nine weeks after tumor injection, mice were sacrificed and tumor nodules analyzed to identify specific immune infiltrates by immunohistochemistry. Ascites, developed in tumor bearing mice over a 10-week period, was characterized by mass cytometry (CyTOF) to qualitatively and quantitatively assess the distribution of the immune cell subsets, and their relationship to ascites from ovarian cancer patients.ResultsTumor nodules in the peritoneal cavity proved to be enriched in T cells, antigen presenting cells and macrophages, demonstrating an active immune environment and cell-mediated immunity. Assessment of the immune landscape in the ascites showed the predominance of CD8+, CD4+, B–, and memory T cells, among others, and the coexistance of different immune cell types within the same tumor microenvironment.ConclusionsWe performed, for the first time, a multiparametric analysis of the ascitic fluid and specifically identify immune cell populations in the peritoneal cavity of mice with advanced OC. Data obtained highlights the impact of CytOF as a diagnostic tool for this malignancy, with the opportunity to concomitantly identify novel targets, and define personalized therapeutic options

    Nanotechnologies in Obstetrics and Cancer during Pregnancy: A Narrative Review

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    Nanotechnology, the art of engineering structures on a molecular level, offers the opportunity to implement new strategies for the diagnosis and management of pregnancy-related disorders. This review aims to summarize the current state of nanotechnology in obstetrics and cancer in pregnancy, focusing on existing and potential applications, and provides insights on safety and future directions. A systematic and comprehensive literature assessment was performed, querying the following databases: PubMed/Medline, Scopus, and Endbase. The databases were searched from their inception to 22 March 2022. Five independent reviewers screened the items and extracted those which were more pertinent within the scope of this review. Although nanotechnology has been on the bench for many years, most of the studies in obstetrics are preclinical. Ongoing research spans from the development of diagnostic tools, including optimized strategies to selectively confine contrast agents in the maternal bloodstream and approaches to improve diagnostics tests to be used in obstetrics, to the synthesis of innovative delivery nanosystems for therapeutic interventions. Using nanotechnology to achieve spatial and temporal control over the delivery of therapeutic agents (e.g., commonly used drugs, more recently defined formulations, or gene therapy-based approaches) offers significant advantages, including the possibility to target specific cells/tissues of interest (e.g., the maternal bloodstream, uterus wall, or fetal compartment). This characteristic of nanotechnology-driven therapy reduces side effects and the amount of therapeutic agent used. However, nanotoxicology appears to be a significant obstacle to adopting these technologies in clinical therapeutic praxis. Further research is needed in order to improve these techniques, as they have tremendous potential to improve the accuracy of the tests applied in clinical praxis. This review showed the increasing interest in nanotechnology applications in obstetrics disorders and pregnancy-related pathologies to improve the diagnostic algorithms, monitor pregnancy-related diseases, and implement new treatment strategies

    the isolpharm project a new isol production method of high specific activity beta emitting radionuclides as radiopharmaceutical precursors

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    The ISOLPHARM project explores the feasibility of exploiting an innovative technology to produce extremely high specific activity beta-emitting radionuclides as radiopharmaceutical precursors. This technique is expected to produce radiopharmaceuticals that are virtually mainly impossible to obtain in standard production facilities, at lower cost and with less environmental impact than traditional techniques. The groundbreaking ISOLPHARM method investigated in this project has been granted an international patent (INFN). As a component of the SPES (Selective Production of Exotic Species) project at the Istituto Nazionale di Fisica Nucleare–Laboratori Nazionali di Legnaro (INFN–LNL), a new facility will produce radioactive ion beams of neutron-rich nuclei with high purity and a mass range of 80–160 amu. The radioactive isotopes will result from nuclear reactions induced by accelerating 40 MeV protons in a cyclotron to collide on a target of UC[Formula: see text]. The uranium in the target material will be [Formula: see text]U, yielding radioactive isotopes that belong to elements with an atomic number between 28 and 57. Isotope separation on line (ISOL) is adopted in the ISOLPHARM project to obtain pure isobaric beams for radiopharmaceutical applications, with no isotopic contaminations in the beam or subsequent trapping substrate. Isobaric contaminations may potentially affect radiochemical and radionuclide purity, but proper methods to separate chemically different elements can be developed
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