2,968 research outputs found

    An a posteriori error analysis of a mixed finite element Galerkin approximation to second order linear parabolic problems

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    In this article, a posteriori error estimates are derived for a mixed finite element Galerkin approximation to second order linear parabolic initial and boundary value problems. Using mixed elliptic reconstruction method, a posteriori error estimates in L∞(L2)L^\infty(L^2) and L2(L2)L^2(L^2)-norms with optimal order of convergence for the solution as well as its flux are proved for the semidiscrete scheme. Finally, based on backward Euler method, a completely discrete scheme is analyzed and a posteriori bounds are derived, which improves earlier results on a posteriori estimates for mixed parabolic problems

    Comparison of the imaging performances for recently developed monolithic scintillators: CRY018 and CRY019 for dual isotope gamma ray imaging applications

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    The growing interest for new scintillation crystals with outstanding imaging performances (i.e. resolution and efficiency) has suggested the study of recently discovered scintillators named CRY018 and CRY019. The crystals under investigation are monolithic and have shown enhanced characteristics both for gamma ray spectrometry and for Nuclear Medicine imaging applications such as the dual isotope imaging. Moreover, the non-hygroscopic nature and the absence of afterglow make these scintillators even more attractive for the potential improvement in a wide range of applications. These scintillation crystals show a high energy resolution in the energy range involved in Nuclear Medicine, allowing the discrimination between very close energy values. Moreover, in order to prove their suitability of being powerful imaging systems, the imaging performances like the position linearity and the intrinsic spatial resolution have been evaluated obtaining satisfactory results thanks to the implementation of an optimized algorithm for the images reconstruction. © 2017 IOP Publishing Ltd and Sissa Medialab srl

    Systematic Data Monitoring and Analysis of Cardiovascular Off-label Prescriptions in Pediatrics: Focus on Angiotensin-Converting Enzyme Inhibitors (ACE-I) and Beta Blockers

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    Introduction: Many efforts have been made to stimulate clinical trials (CTs) in pediatrics but most of the drugs are still authorized only in adults and used off-label in the pediatric population. Aim: To assess how widespread is the off-label prescription in Italy and to identify areas of unmet medical need by applying a model for the systematic collection and analysis of data. Methods: A study was performed using 2015 data from the Italian Medicines Utilization Monitoring Centre Health Database (OsMed). A study sample of 3,726,583 pediatric patients, was considered. Cardiovascular drugs were selected for this study. Assessment of the off-label use, the analysis of the pharmacovigilance signals, a bibliographic research and the analysis of ongoing CTs were carried out. Results: In 2015, 8,544 pediatric patients received treatment with a cardiovascular drug. Angiotensin converting enzyme inhibitors (ACE-I) followed by beta blockers agents are the most prescribed molecules. Eight molecules were selected and an in-depth analysis conducted. The PhV network showed only one record of adverse reaction as off-label in 2015. The results show several therapeutic areas of use in pediatrics. Conclusion: Off-label in pediatrics is largely widespread in Europe and US and our results show it is also present in Italy. Molecules selected are used off-label for therapeutic areas such as oncologic, hematological and rare diseases. Results of pharmacovigilance suggests underreporting. The analysis carried out in this study could be an open track for a systematic monitoring activity and of interest for prescribers, pediatricians and other healthcare professionals during the clinical practice

    Genotype x environment interactions in sire evaluation

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    Part of Ph. D thesis submitted by S.N. Pani ... --P. [4].Digitized 2007 AES MoU.Includes bibliographical references (page [24])

    Mental health research projects: a practical integration of mental health into a medical curriculum

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    Abstract of a paper presented at the 65th Annual National Conference of Indian Psychiatric Society, Bangalor, 10-13 Jan, 2013. Aims aJld Objectives: The University of Wollongong (UoW) graduate-entry medical course embeds research and critical analysis within the curriculum, concluding with students undertaking a regional/ nlrsl conmlUnity-based ro earch project. Students are encouraged to design a research project of interest to them and the local community. T.his Indy analyzed whether conducting research projects enhanced learning/understanding about rural/regional mental health issues amongst UoW medical students

    A Geant4 simulation code for simulating optical photons in SPECT scintillation detectors

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    Geant4 is an object oriented toolkit created for the simulation of High-Energy Physics detectors. Geant4 allows an accurate modeling of radiation sources and detector devices, with easy configuration and friendly interface and at the same time with great accuracy in the simulation of physical processes. While most Monte Carlo codes do not allow the simulation of the transport and boundary characteristics for optical photons transport generated by scintillating crystal, Geant4 allows the simulation of the optical photons. In this paper we present an application of the Geant4 program for simulating optical photons in SPECT cameras. We aim to study the light transport within scintillators, photomultiplier tubes and coupling devices. To this end, we simulated a detector based on a scintillator, coupled to a photomultiplier tube through a glass window. We compared simulated results with experimental data and theoretical models, in order to verify the good matching with our simulations. We simulated a pencil beam of 140 keV photons impinging the crystal at different locations. For each condition, we calculated the value of the Pulse Height Centroid and the spread of the charge distribution, as read out by the anode array of the photomultiplier. Finally, the spatial and the energy resolutions of the camera have been estimated by simulated data. In all cases, we found that simulations agree very well with experimental data
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