1,820 research outputs found

    A Combination of Artificial Ground Freezing and Grouting for the Excavation of a Large Size Tunnel Below Groundwater

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    Within the Metro Line 1 extension project in Napoli (Italy), the service tunnel at Toledo station was one of the most critical sections of the project. The 13m wide, 17m high, 40m long tunnel is located downtown under a deeply urbanized area. It was excavated starting from an access shaft and from this tunnel four platform tunnels are under excavation. The geology of the site is characterized by volcanic soils: loose pozzolana silty sand and tuff. The underground works were carried out under a hydrostatic head of 27 m. In order to allow a safe and substantially dry excavation, soil/rock improvements were carried out by a combination of two different methods: cement and chemical grouting at the sides and invert (in tuff) and Artificial Ground Freezing (AGF) at the crown (in pozzolana). The treatments were carried out both from a drift located approximately 10 m above the crown and from the access shaft. The grouting process was controlled and monitored by a computerized system. To check the development and the efficacy of the freezing process, suitable sensors and automatic data acquisition and recording systems were installed. The variation of the temperature within the soil and the cooling fluids were monitored during the entire freezing operation

    SARS-CoV2 vaccination adverse events trend in Italy. A retrospective interpretation of the last year (december 2020-eptember 2021)

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    At the end of 2020, a vaccination campaign against COVID-19 was launched. In 2021, legal obligations for health workers, as well as specific regulations for all workers, were introduced. The global SARS-CoV-2 pandemic was followed by epochal changes in life, school, and work habits in Italy. Therefore, the pharmacovigilance work currently being conducted in Italy by the AIFA concerning the recording and analysing of adverse reactions related to the use of vaccines has proved to be very important. The latest report, including a period of 10 months from December 2020 to September 2021, has allowed us to combine the results received so far, and to compare the safety of all vaccines currently available in Italy. The results of this analysis are highly encouraging and reveal the statistical reliability of the safety of the COVID-19 vaccines currently used in Italy. The dissemination of these findings could increase the public's awareness of vaccines and their ability to make free and informed choices concerning vaccination. The potential increase in the Italian population's adherence to the vaccination campaign could ultimately be a decisive factor in achieving herd immunity and the final resolution of the pandemic

    Freestanding Cellulose Acetate/ZnO Flowers Composites for Solar Photocatalysis and Controlled Zinc Ions Release

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    The versatile properties of ZnO micro- and nano- structures have resulted in many applications in piezotronics, biosensors and photocatalysis. However, ZnO can easily dissolve in aqueous fluids, potentially resulting in the release of reactive oxygen species and zinc ions at toxic concentrations. Such an issue can be solved by dispersing ZnO within biocompatible polymeric matrices to reduce the direct exposure to the aqueous fluid and control the release of zinc ions. Herein, this work explores tailored ZnO flowers/cellulose acetate photocatalytic composites at different ZnO weight percentages (1-15 wt%). The photocatalytic degradation of methylene blue dye under simulated solar light is studied, finding an optimal value of ZnO filler loading in the polymer (10 wt %), resulting from a compromise between the photodegradation efficiency and the hydrophobicity induced by ZnO flowers. The reusability of the composites is investigated, finding a surprising improvement in the photodegradation efficiency after the first cycle. Simulated solar light stimulation induces the controllable release of zinc ions in aqueous solution at ppm-levels from the composites at the optimal ZnO filler loading. Finally, the release of ionic species in the absence of light stimulation is found to be directly proportional to the ZnO-loading in the composite, as a result of its degradation in aqueous environments

    Preliminary Design and Validation of the Automation Logic Supervisor Module for an Integrated Mission Management System

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    This paper is focused on the design, implementation and validation, in the MATLAB/Simulink/Stateflow environment, of a software prototype, named Automation Logic Supervisor (ALS) module, for the internal execution logic automation of the various systems constituting an Integrated Mission Management System (IMMS). The Automation Logic Supervisor module has been developed by CIRA as a part of a thesis work within the international project COAST (Cost Optimized Avionics System), funded by the European Union in the framework of the Clean Sky 2 - Systems ITD Programme, in which CIRA is a core partner. In the paper, after an introduction about the operational framework and motivations of the ALS design, it is described the preliminary conceptual design of the module, emphasizing the various considered logical states and their connections and associated transition conditions. Then, the implementation of the ALS as preliminary software prototype in Matlab/Simulink/Stateflow nvironment is outlined. Finally, the numerical validation of the ALS model is described, by outlining the considered test scenarios, which have been on purpose defined to stimulate all the ALS finite state machine modelled transitions, and reporting the results of the numerical simulations that show the correct behavior of the ALS, whose development successfully reached TRL 3

    Design Consideration on a Polarized Gas Target for the LHC

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    Since 2017, the LHCSpin study group is investigating the installation of a HERMES-type polarized gas target (PGT) in front of the LHCb detector in order to perform Single-Spin Transverse Asymmetry (SSTA) measurements. In cooperation with LHC experts, the conditions for applying a PGT are being studied. As a viable option, a cold openable storage cell is considered. A key role for avoiding instabilities of the 7 TeV proton beam is the choice of a proper coating and the suppression of wake fields. A first warm (300 K) test storage cell is planned for installation in 2019 inside the VELO vessel, subject to final approval. It will improve the ongoing SMOG program of LHCb fixed target measurements, and will provide valuable experience of running a storage cell in the harsh LHC environment. The status of the design considerations on a PGT in the LHC beam and of the discussion of critical machine issues is presented.Comment: 8 pages, 7 figures, 11 reference

    Normal versus pathological cardiac fibroblast-derived extracellular matrix differentially modulates cardiosphere-derived cell paracrine properties and commitment

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    Human resident cardiac progenitor cells (CPCs) isolated as cardiosphere-derived cells (CDCs) are under clinical evaluation as a therapeutic product for cardiac regenerative medicine. Unfortunately, limited engraftment and differentiation potential of transplanted cells significantly hamper therapeutic success. Moreover, maladaptive remodelling of the extracellular matrix (ECM) during heart failure progression provides impaired biological and mechanical signals to cardiac cells, including CPCs. In this study, we aimed at investigating the differential effect on the phenotype of human CDCs of cardiac fibroblast-derived ECM substrates from healthy or diseased hearts, named, respectively, normal or pathological cardiogel (CG-N/P). After 7 days of culture, results show increased levels of cardiogenic gene expression (NKX2.5, CX43) on both decellularized cardiogels compared to control, while the proportion and staining patterns of GATA4, OCT4, NKX2.5, ACTA1, VIM, and CD90-positive CPCs were not affected, as assessed by immunofluorescence microscopy and flow cytometry analyses. Nonetheless, CDCs cultured on CG-N secreted significantly higher levels of osteopontin, FGF6, FGF7, NT-3, IGFBP4, and TIMP-2 compared to those cultured on CG-P, suggesting overall a reduced trophic and antiremodelling paracrine profile of CDCs when in contact with ECM from pathological cardiac fibroblasts. These results provide novel insights into the bidirectional interplay between cardiac ECM and CPCs, potentially affecting CPC biology and regenerative potential

    Sphingolipids and impaired hypoxic stress responses in Huntington disease.

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    Huntington disease (HD) is a debilitating, currently incurable disease. Protein aggregation and metabolic deficits are pathological hallmarks but their link to neurodegeneration and symptoms remains debated. Here, we summarize alterations in the levels of different sphingolipids in an attempt to characterize sphingolipid patterns specific to HD, an additional molecular hallmark of the disease. Based on the crucial role of sphingolipids in maintaining cellular homeostasis, the dynamic regulation of sphingolipids upon insults and their involvement in cellular stress responses, we hypothesize that maladaptations or blunted adaptations, especially following cellular stress due to reduced oxygen supply (hypoxia) contribute to the development of pathology in HD. We review how sphingolipids shape cellular energy metabolism and control proteostasis and suggest how these functions may fail in HD and in combination with additional insults. Finally, we evaluate the potential of improving cellular resilience in HD by conditioning approaches (improving the efficiency of cellular stress responses) and the role of sphingolipids therein. Sphingolipid metabolism is crucial for cellular homeostasis and for adaptations following cellular stress, including hypoxia. Inadequate cellular management of hypoxic stress likely contributes to HD progression, and sphingolipids are potential mediators. Targeting sphingolipids and the hypoxic stress response are novel treatment strategies for HD
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