4,300 research outputs found

    Political Integration: An Analysis of the British White Paper on Northern Ireland

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    Political Scienc

    Extending displacement-based earthquake loss assessment (DBELA) for the computation of fragility curves

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    This paper presents a new procedure to derive fragility functions for populations of buildings that relies on the displacement-based earthquake loss assessment (DBELA) methodology. In the method proposed herein, thousands of synthetic buildings have been produced considering the probabilistic distribution describing the variability in geometrical and material properties. Then, their nonlinear capacity has been estimated using the DBELA method and their response against a large set of ground motion records has been estimated. Global limit states are used to estimate the distribution of buildings in each damage state for different levels of ground motion, and a regression algorithm is applied to derive fragility functions for each limit state. The proposed methodology is demonstrated for the case of ductile and non-ductile Turkish reinforced concrete frames with masonry infills

    Gli effetti dell’introduzione della nuova mappa di pericolosità sulla valutazione del rischio sismico in Italia.

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    L’introduzione di una versione aggiornata della mappa di pericolositĂ  sismica, definita per diversi periodi di ritorno e per svariati valori di ordinate spettrali, porta inevitabilmente a dei cambiamenti sul livello di rischio sismico del costruito italiano. PoichĂ© la relazione tra domanda e capacitĂ  non Ăš lineare per tutto il range di periodi di vibrazione strutturale, Ăš necessario valutare il cambiamento del livello di rischio sismico calcolando esplicitamente la vulnerabilitĂ  sismica di strutture esistenti con diversi periodi di vibrazione, per diversi stati limite e considerando sia la nuova che la precedente definizione di pericolositĂ . Nel presente lavoro Ăš stato eseguito un primo studio degli effetti che l’introduzione di mappe aggiornate della pericolositĂ  sismica potrebbe avere sulla valutazione dei livelli di rischio sismico nel territorio italiano. Le caratteristiche generali del costruito sono state ricavate dai dati del 14° Censimento Generale della Popolazione e delle Abitazioni (ISTAT 2001), mentre una procedura probabilistica di valutazione sismica per edifici esistenti a scala urbana Ăš stata impiegata per stimare la capacitĂ . Sono stati considerati tutti i tre stati limite prescritti dall’Ordinanza (danno lieve, danno severo, collasso) in corrispondenza dei rispettivi valori di domanda, cosĂŹ come il cambiamento delle forme spettrali in funzione della localizzazione e del periodo di ritorno. I risultati dimostrano che la nuova mappa di pericolositĂ  sismica porta a dei livelli di rischio sismico piĂč realistici e meno allarmanti, rendendo leggermente meno gravoso, anche se non privo di problematiche, il panorama attuale di rischio in Italia

    Masonry components

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    Masonry is a non-homogeneous material, composed of units and mortar, which can be of different types, with distinct mechanical properties. The design of both masonry units and mortar is based on the role of the walls in the building. Load-bearing walls relate to structural elements that bear mainly vertical loads, but can serve also to resist to horizontal loads. When a structural masonry building is submitted to in-plane and out-of-plane loadings induced by an earthquake for example, the masonry walls are the structural elements that ensure the global stability of the building. This means that the walls should have adequate mechanical properties that enable them to resist to different combinations of compressive, shear and tensile stresses.The boundary conditions influence the resisting mechanisms of the structural walls under in-plane loading and in a buildings the connection at the intersection walls are of paramount importance for the out-of-plane resisting mechanism. However, it is well established that the masonry mechanical properties are also relevant for the global mechanical performance of the structural masonry walls. Masonry units for load-bearing walls are usually laid so that their perforations are vertically oriented, whereas for partition walls, brick units with horizontal perforation are mostly adopted

    Bright galaxies at Hubble's redshift detection frontier: Preliminary results and design from the redshift z~9-10 BoRG pure-parallel HST survey

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    We present the first results and design from the redshift z~9-10 Brightest of the Reionizing Galaxies {\it Hubble Space Telescope} survey BoRG[z9-10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9-10] is the continuation of a multi-year pure-parallel near-IR and optical imaging campaign with the Wide Field Camera 3. The ongoing survey uses five filters, optimized for detecting the most distant objects and offering continuous wavelength coverage from {\lambda}=0.35{\mu}m to {\lambda}=1.7{\mu}m. We analyze the initial ~130 arcmin2^2 of area over 28 independent lines of sight (~25% of the total planned) to search for z>7 galaxies using a combination of Lyman break and photometric redshift selections. From an effective comoving volume of (5-25) times105times 10^5 Mpc3^3 for magnitudes brighter than mAB=26.5−24.0m_{AB}=26.5-24.0 in the H160H_{160}-band respectively, we find five galaxy candidates at z~8.3-10 detected at high confidence (S/N>8), including a source at z~8.4 with mAB=24.5 (S/N~22), which, if confirmed, would be the brightest galaxy identified at such early times (z>8). In addition, BoRG[z9-10] data yield four galaxies with 7.3â‰Čzâ‰Č87.3 \lesssim z \lesssim 8. These new Lyman break galaxies with mâ‰Č26.5\lesssim26.5 are ideal targets for follow-up observations from ground and space based observatories to help investigate the complex interplay between dark matter growth, galaxy assembly, and reionization.Comment: Accepted for publication on ApJ. 21 pages, 11 figures, 4 table

    Naturally presented HLA class I-restricted epitopes from the neurotrophic factor S100-? are targets of the autoimmune response in type 1 diabetes

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    Type 1 diabetes (T1D) results from the destruction of pancreatic beta-cells by the immune system, and CD8(+) T lymphocytes are critical actors in this autoimmune response. Pancreatic islets are surrounded by a mesh of nervous cells, the peri-insular Schwann cells, which are also targeted by autoreactive T lymphocytes and express specific antigens, such as the neurotrophic factor S100-beta. Previous work has shown increased proliferative responses to whole S100-beta in both human T1D patients and the nonobese diabetic (NOD) mouse model. We describe for the first time naturally processed and presented epitopes (NPPEs) presented by class I human leukocyte antigen-A*02:01 (A2.1) molecules derived from S100-beta. These NPPEs triggered IFN-gamma responses more frequently in both newly diagnosed and long-term T1D patients compared with healthy donors. Furthermore, the same NPPEs are recognized during the autoimmune response leading to diabetes in A2.1-transgenic NOD mice as early as 4 wk of age. Interestingly, when these NPPEs are used to prevent diabetes in this animal model, an acceleration of the disease is observed together with an exacerbation in insulitis and an increase in S100-beta-specific cytotoxicity in vaccinated animals. Whether these can be used in diabetes prevention needs to be carefully evaluated in animal models before use in future clinical assays.-Calvino-Sampedro, C., Gomez-Tourino, I., Cordero, O. J., Reche, P. A., Gomez-Perosanz, M., Sanchez-Trincado, J. L., Rodriguez, M. A., Sueiro, A. M., Vinuela, J. E., Calvino, R. V. Naturally presented HLA class I-restricted epitopes from the neurotrophic factor S100-beta are targets of the autoimmune response in type 1 diabetes

    Seismic hazard data for the new, Italian building code based on European standard

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    Prior to 2003 the Italian building code, established in 1974, was mostly based on working stress design. The zonation that guided its application was made up in 1981 using a semi-quantitative, mainly seismological approach; it was enforced in 1984 and left about 2/3 of the territory without seismic provisions. In 1998 a new zonation was proposed but never adopted. The 2002 Mw5.7 earthquake in Molise (Southern Italy) caused the collapse of a school and the death of 26 children. The school was built in an area where seismic provisions were not applied, although the zonation proposed in 1998 assigned it to the second zone. The earthquake triggered a process that led in a few months to a new set of seismic provision

    Gas-phase metallicity of 27 galaxies at intermediate redshift

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    The purpose of this work is to make available new gas-phase oxygen abundance measurements for a serendipitous sample of 27 galaxies with redshift 0.35<z<0.52. We measured the equivalent widths of the [O II]{\lambda}3727, H{\beta}, and [O III]{\lambda}{\lambda}4959, 5007 emission lines observed in the galaxy spectra obtained with the Visible Multi-Object Spectrograph mounted at the Very Large Telescope. For each galaxy, we derived the metallicity-sensitive emission lines ratio R23, ionization-sensitive emission lines ratio O32, and gas-phase oxygen abundance 12+log(O/H). The values of gas-phase oxygen abundance 12+log(O/H) we obtained for the sample galaxies are consistent with previous findings for galaxies at intermediate redshift.Comment: 5 pages, 3 postscript figures and 3 tables. A&A in pres
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