471 research outputs found

    Evaluation of FRP concrete compression member under repeated load and harsh environment

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    Strengthening and rehabilitation have been increasingly applied in many structures to improve their capacity and serviceability. Fiber Reinforced Polymer (FRP) materials are universally known for their ability to improve the load capacity of damaged structural elements because of their high linear-elastic behavior. However, enhancing the capacity of structural elements that are exposed to repeated load coupled with harsh environment is an area that requires further investigation. This research focused on experimental analysis of the behavior and response of confined and unconfined concrete compression members (300mm x 150mm) under repeated load while exposed to 1440 cycles of seawater splash zone in United Arab Emirates (UAE). Confining concrete compression members with Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP) sheets have increased the load capacity compared to the control sample at room temperature by 110% and 84%, respectively. Results showed that the average value of compressive strength for the confined concrete exposed to sea water splash zone conditions for CFRP and GFRP specimens has decreased by 33% and 23%, respectively, compared to the confined concrete in the room temperature. However, GFRP specimens showed higher performance in compressive strength under sea water splash zone than those of the CFRP specimens. Different mode of failures such as delamination, de-bonding and combination of such modes were observed and related to various exposure factors and mechanical properties

    Autoantibodies Status of Leishmanial Patients in Iraq

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    A total of 145 leishmaniasis Iraqi patients were collected from suspected cases and 30 healthy control. Based on skin smear examination and serum samples analysis, the patients were distributed into two clinical groups: 30 cutaneous leishmaniasis and 30 visceral leishmaniasis patients. The study was conducted for the detection of 17 types of antinuclear autoantibodies (ANA) in studied groups, 10 types including (anti-ds-DNA, anti-Nucleosome, anti-SmD1, anti-PCNA, anti-SS-A/Ro60kD, anti-SS-A/Ro52kD, anti-SS-B/La, anti-CENP-B, anti-Mi-2 and anti-Ku antibodies), showed significant differences (P?0.05), (P?0.01) in the two groups, while 7 types which were non-significant included (anti-histones, anti-ribosomal P0, anti-Scl70, anti-U1-snRNP, anti-AMA M2, anti-Jo1 and anti-PM-Scl antibodies). With respect to the Anti-cardiolipin IgG antibodies (aCL), it showed a significant increased level in the serum of VL patients (P?0.01) as compared with control group (8.123 vs. 1.959), also as compared with CL patients (8.123 vs. 2.402). As for CL patients, also there was a significant difference (P?0.01) (2.402 vs. 8.123) when compared with VL patients, but no significant variations (2.402 vs. 1.959) were observed in compare with control group. We conclude that Leishmaniasis in iraqi patients may be considered as a cause autoimmune diseases as in case of inflammatory myopathies (IM), and the pathgenesis of human myositis, especially in VL which contributes in the immunological alterations associated with muscle damage. Keywords: Leishmania species, autoantibodies, antinuclear antibodies, anticardiolipin

    Type 2 myocardial infarction: a diagnostic and therapeutic challenge in contemporary cardiology

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    In the expanding world of cardiovascular diseases, rapidly reaching pandemic proportions, the main focus is still on coronary atherosclerosis and its clinical consequences. However, at least in the Western world, middle-aged male patients with acute myocardial infarction are no more the rule. Due to a higher life expectancy and major medical advances, physicians are to treat older and frailer individuals, usually with multiple comorbidities. In this context, myocardial ischaemia and infarction frequently result from an imbalance between myocardial oxygen supply and demand\u2014i.e., type 2 myocardial infarction (T2MI), according to the current universal definition\u2014rather than coronary atherothrombosis. Moreover, the increasing use of high-sensitivity cardiac troponin assays has led to a heightened detection of T2MI\u2014often causing relatively little myocardial injury\u2014, which seems to have doubled its numbers in recent years. Nevertheless, owing to its multifaceted pathophysiology and clinical presentation, T2MI is still underdiagnosed. Perhaps more importantly, T2MI is also victim of undertreatment, as drugs that constitute the cornerstone of therapy in most cardiovascular diseases are much more unlikely to be prescribed in T2MI than in coronary atherothrombosis. In this paper, we review the recent literature on the classification, pathophysiology, epidemiology, and management of T2MI, trying to summarise the state-of-the-art knowledge about this increasingly important pathologic condition. Finally, based on the current scientific evidence, we also propose an algorithm that may be easily utilised in clinical practice, in order to improve T2MI diagnosis and risk stratification

    Toward validation of simulated accelerograms via prediction equations for nonlinear SDOF response

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    Seismic structural risk analysis of critical facilities may require nonlinear dynamic analysis for which record selection is one of the key issues. Notwithstanding the increasing availability of database of strong-motion records, it may be hard to find accelerograms that fit a specific scenario (e.g., in terms of magnitude and distance) resulting from hazard assessment at the site of interest. A possible, alternative, approach can be the use of artificial and/or simulated ground motion in lieu of real records. Their employment requires systematic engineering validation in terms of structural response and/or seismic risk. Prediction equations for peak and cyclic inelastic single degree of freedom systems’ response, based on Italian accelerometric data, are discussed in this study as a possible benchmark, alongside real record counterparts, for the validation of synthetic records. Even if multiple events would be in principle required, an extremely preliminary validation is carried out considering only four simulated records of the 1980 Irpinia (southern Italy) M w 6.9 earthquake. Simulated records are obtained through a broadband hybrid integral-composite technique. Results show how this simulation method may lead to generally acceptable results. It is also emphasized how this kind of validation may provide additional results with respect to classical signal-to-signal comparison of real and simulated records

    Linear stability analysis of the flow between rotating cylinders of wide gap

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    © 2018 The Authors. Published by Elsevier. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1016/j.euromechflu.2018.07.002© 2018 The Authors This study investigated by an analytical method the flow that develops in the gap between concentric rotating cylinders when the Taylor number Ta exceeds the first critical value. Concentric cylinders rotating at the speed ratio μ=0 are investigated over the radius ratio range 0.20≤η≤0.95. This range includes configurations characterised by a larger annular gap width d than classical journal bearing test cases and by a Taylor number beyond the first critical Taylor number at which Taylor vortices develop. The analysis focuses on determining the parameters for the direct transition from axisymmetric Couette flow to wavy Taylor vortex flow. The results show a marked change in trend as the radius ratio η reduces below 0.49 and 0.63 for the azimuthal wave-numbers m=2 and 3 respectively. The axial wavenumber increases so that the resulting wavy Taylor vortex flow is characterised by vortex structures elongated in the radial direction, with a meridional cross-section that is significantly elliptical. The linear stability analysis of the perturbation equations suggests this instability pattern is neutrally stable. Whereas a direct transition from axisymmetric Couette flow is not necessarily the only route for the onset of wavy Taylor vortex flow, the significant difference between the predicted pattern at large gap widths and classical wavy Taylor vortex flow merits further investigation.This project has been supported by a Specific Targeted Research Project of the European Community’s Sixth Framework Programme under contract number NMP3-CT-2006-032669 (PROVAEN). The original acquisition of MATLAB software licenses was part-funded by EPSRC grant GR/N23745/01.Published versio

    In Vitro Activities of Ertapenem and Imipenem against Clinical Extended Spectrum Beta-Lactamase-Producing Enterobacteriaceae Collected in Military Teaching Hospital Mohammed V of Rabat

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    Objective. To study the sensitivity level of extended spectrum beta-lactamase-producing Enterobacteriaceae to Carbapenems (Imipenem, Ertapenem) marketed in Morocco and discusses the place of Ertapenem in the treatment of extended spectrum-beta-lactamase-producing. Materials and Methods. A retrospective study of 110 extended spectrum beta-lactamase-producing Enterobacteriaceae. Isolates obtained from blood cultures, superficial and deep pus, and catheters were conducted. The minimum inhibitory concentrations of Imipenem and Ertapenem were done by the E-test. The modified Hodge test was conducted for resistant or intermediate strains. Results. 99.1% of isolates were susceptible to Imipenem. For Ertapenem, 4 were resistant and 4 intermediate. The modified Hodge test was positive for all 08 isolates. A minimum inhibitory concentration comparison of K. pneumoniae, E. cloacae, and E. coli for Imipenem has noted a significant difference between E. cloacae on one hand and E. coli, K. pneumoniae on the other hand (<0.01). No significant difference was noted for minimum inhibitory concentration of Ertapenem. Conclusion. Our results confirm in vitro effectiveness of Ertapenem against extended spectrum beta-lactamase-producing Enterobacteriaceae as reported elsewhere. However, the emergence of resistance to Carbapenems revealed by production of carbapenemases in this study confirmed a necessary bacteriological documented infection before using Ertapenem

    Diversity of Cardiologic Issues in a Contemporary Cohort of Women With Breast Cancer

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    Background: Women with breast cancer (BC) represent a special population particularly exposed to cardiovascular disease (CVD) risk. However, cardiologic assessment in BC is mostly limited to detection of left ventricular dysfunction cardiotoxicity (LVD-CTX) due to anticancer treatments. Our aim was to comprehensively investigate CV profile and events in a contemporary BC cohort. Methods and Results: Records of BC patients referred for a Cardio-Oncologic evaluation before starting anticancer treatments, between 2016 and 2019, were retrospectively reviewed (n = 508). Information regarding prevalence and control of CV risk factors, and novel CVD diagnoses were extracted. Occurrence of LVD-CTX, CV events other than LVD-CTX and mortality was assessed. Mean age of study population was 64 ± 13 years; 287 patients were scheduled to receive anthracycline and 165 anti-HER2 therapy. Overall, 53% of BC women had ≥2 CV risk factors, and 67% had at least one of arterial hypertension, dyslipidaemia or diabetes mellitus not adequately controlled. Eighteen (4%) patients were diagnosed a previously unknown CVD. Over a mean follow-up of 2.5 ± 1 years, 3% of BC patients developed LVD-CTX, 2% suffered from other CV events and 11% died. CV risk factors were not associated with LVD-CTX, except for family history of CAD. On the contrary, patients with other CV events exhibited a worse CV profile. Those who died more commonly experienced CV events other than LVD-CTX (p = 0.02). Conclusions: BC women show a suboptimal CV risk profile and are at risk of CV events not limited to LVD-CTX. A baseline Cardio-Oncologic evaluation was instrumental to implement CV prevention and to optimize CV therapies

    Quantum correlations and synchronization measures

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    The phenomenon of spontaneous synchronization is universal and only recently advances have been made in the quantum domain. Being synchronization a kind of temporal correlation among systems, it is interesting to understand its connection with other measures of quantum correlations. We review here what is known in the field, putting emphasis on measures and indicators of synchronization which have been proposed in the literature, and comparing their validity for different dynamical systems, highlighting when they give similar insights and when they seem to fail.Comment: book chapter, 18 pages, 7 figures, Fanchini F., Soares Pinto D., Adesso G. (eds) Lectures on General Quantum Correlations and their Applications. Quantum Science and Technology. Springer (2017

    Task 1 - Scenari di scuotimento - Deliverable D0: Tecniche di simulazione

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    Progetto INGV-DPC S3 “Scenari di scuotimento in aree di interesse prioritario e/o strategico”Published4.1. Metodologie sismologiche per l'ingegneria sismicaope

    Caratteristiche dei dati accelerometrici registrati durante la sequenza sismica aquilana

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    I dati accelerometrici relativi alla sequenza sismica de L’Aquila, iniziata con l’evento del 6 Aprile alle ore 1.32 (MW 6.3), provengono dalla rete Rete Accelerometrica Nazionale (RAN), gestita dal Dipartimento della Protezione Civile (DPC) e da una rete temporanea installata il giorno dopo la scossa principale ad opera dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV MI-PV). I dati del DPC sono scaricabili dalla banca dati accelerometrica italiana ITACA (http://itaca.mi.ingv.it), mentre quelli dell'INGV sono accessibili dal sito Internet http://accel.mi.ingv.it/statiche/ABRUZZO-2009/main.html. Il terremoto de L’Aquila è il terzo evento più forte che abbia prodotto registrazioni accelerometriche in Italia, dopo i terremoti dell’Irpinia (1980, MW 6.9) e del Friuli (1976, MW 6.4). Questo evento, insieme alle 12 repliche più forti (MW > 4.0) ha fornito un insieme di dati accelerometrici unico in Italia, in particolare per la presenza di un numero consistente di registrazioni in zona epicentrale ("campo vicino"). Il data set è composto da circa 300 accelerogrammi digitali (di cui 270 provenienti dalla RAN), con un ottimo rapporto segnale/rumore, registrati da circa 70 stazioni, installate in varie condizioni di sito, a distanze comprese fra 0 e 300 km. L'importanza di questo data set, non solo a livello nazionale, è legato al contributo significativo che fornisce nel colmare una lacuna nella distribuzione magnitudo-distanza dei dati strong motion italiani e mondiali, soprattutto per quanto riguarda gli eventi con meccanismo di faglia normale (Ameri et al.; 2009). I dati registrati in campo vicino provengono da un transetto composto da 6 stazioni installato dalla Protezione Civile nel 2001 nella Alta Valle dell’Aterno, con lo scopo di investigare la variabilità del moto sismico rispetto alle condizioni geologiche locali, dalla stazione AQK, installata in prossimità del centro urbano e da una stazione (AQU) appartenente alla rete broad band Mednet (http://mednet.rm.ingv.it/data.php), situata nel castello de L’Aquila. Queste stazioni distano meno di 5 km dall’epicentro dell’evento principale, ricadendo all’interno della proiezione superficiale del piano di rottura. A queste si aggiungono le registrazioni delle repliche, ottenute dalle stazioni della rete temporanea INGV, installata in area epicentrale. In questo lavoro si presenta un resoconto delle principali caratteristiche dello scuotimento del suolo verificatosi durante la sequenza sismica aquilana, attraverso l’analisi dei dati accelerometrici relativi alla scossa principale e alle due repliche più forti. Si discutono in particolare la dipendenza di diversi parametri strong motion dalla distanza, dall’azimuth e dalle condizioni di sito, e l'effetto delle caratteristiche del moto in campo vicino sulla risposta strutturalePublished57-684.1. Metodologie sismologiche per l'ingegneria sismicaN/A or not JCRreserve
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