183 research outputs found

    An off-shell I.R. regularization strategy in the analysis of collinear divergences

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    We present a method for the analysis of singularities of Feynman amplitudes based on the Speer sector decomposition of the Schwinger parametric integrals combined with the Mellin-Barnes transform. The sector decomposition method is described in some details. We suggest the idea of applying the method to the analysis of collinear singularities in inclusive QCD cross sections in the mass-less limit regularizing the forward amplitudes by an off-shell choice of the initial particle momenta. It is shown how the suggested strategy works in the well known case of the one loop corrections to Deep Inelastic Scattering.Comment: 25 pages, 3 figure

    La realidad virtual como entorno fortalecedor para el cambio personal: la contribución del laboratorio de tecnología aplicada a la neuropsicología

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    When we exercise real choice, we gain increased control over our lives and are able to change ourselves. However for many subjects it is not easy to exercise effective choices: patients often don’t have the knowledge, skills, assertiveness, or self esteem needed. In this situation Virtual Reality (VR), an artificial reality that projects the user into a 3D space generated by the computer, may offer a critical advantage to the therapist. The enriched experience and the total level of control on its features, transform VR in an “empowering environment”, where patients can start to explore and act without feeling actually threatened. The attempt of defining, developing and testing VR tools supporting personal empowerment is the main goal of the Applied Technology for Neuro-Psychology Laboratory –ATN-P Lab– at the Istituto Auxologico Italiano. The paper describes the actual work done by the ATN-P Lab. in this area. Specifically, the open source "NeuroVR" system and its potential clinical applications –anxiety disorders, obesity and eating disorders– are presented and discussed.La capacidad de elección nos proporciona control sobre nuestras vidas y nos ofrece posibilidades de cambio. Sin embargo, para muchas personas no es fácil realizar elecciones efectivas; por ejemplo, los pacientes carecen muchas veces del conocimiento, la habilidad, la asertividad o autoestima necesarias. En esas situaciones, la realidad virtual (RV), una realidad artificial que coloca al sujeto en un espacio generado por el ordenador, puede ser para el terapeuta un recurso decisivo. La experiencia enriquecida y el control total sobre todos sus aspectos transforman la RV en un “entorno fortalecedor”, en el que los pacientes pueden comenzar a explorar y actuar sin sentirse amenazados. El principal objetivo del “Applied Technology for Neuro-Psychology Laboratory” (ATN-P Lab), perteneciente al Instituto Auxologico Italiano, es intentar definir, desarrollar y probar aplicaciones basadas en RV que faciliten el fortalecimiento personal. En este artículo se describe el trabajo que se viene realizando sobre este tema en ese laboratorio. Se presenta y discute, específicamente, el sistema de código abierto denominado “NeuroVR”, así como sus aplicaciones clínicas potenciales sobre los trastornos de ansiedad, la obesidad y los trastornos alimentarios

    The use of Biofeedback in Clinical Virtual Reality: The INTREPID Project

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    Generalized anxiety disorder (GAD) is a psychiatric disorder characterized by a constant and unspecific anxiety that interferes with daily-life activities. Its high prevalence in general population and the severe limitations it causes, point out the necessity to find new efficient strategies to treat it. Together with the cognitive-behavioral treatments, relaxation represents a useful approach for the treatment of GAD, but it has the limitation that it is hard to be learned. The INTREPID project is aimed to implement a new instrument to treat anxiety-related disorders and to test its clinical efficacy in reducing anxiety-related symptoms. The innovation of this approach is the combination of virtual reality and biofeedback, so that the first one is directly modified by the output of the second one. In this way, the patient is made aware of his or her reactions through the modification of some features of the VR environment in real time. Using mental exercises the patient learns to control these physiological parameters and using the feedback provided by the virtual environment is able to gauge his or her success. The supplemental use of portable devices, such as PDA or smart-phones, allows the patient to perform at home, individually and autonomously, the same exercises experienced in therapist's office. The goal is to anchor the learned protocol in a real life context, so enhancing the patients' ability to deal with their symptoms. The expected result is a better and faster learning of relaxation techniques, and thus an increased effectiveness of the treatment if compared with traditional clinical protocols

    La realidad virtual como entorno fortalecedor para el cambio personal: la contribución del laboratorio de tecnología aplicada a la neuropsicología

    Get PDF
    When we exercise real choice, we gain increased control over our lives and are able to change ourselves. However for many subjects it is not easy to exercise effective choices: patients often don’t have the knowledge, skills, assertiveness, or self esteem needed. In this situation Virtual Reality (VR), an artificial reality that projects the user into a 3D space generated by the computer, may offer a critical advantage to the therapist. The enriched experience and the total level of control on its features, transform VR in an “empowering environment”, where patients can start to explore and act without feeling actually threatened. The attempt of defining, developing and testing VR tools supporting personal empowerment is the main goal of the Applied Technology for Neuro-Psychology Laboratory –ATN-P Lab– at the Istituto Auxologico Italiano. The paper describes the actual work done by the ATN-P Lab. in this area. Specifically, the open source "NeuroVR" system and its potential clinical applications –anxiety disorders, obesity and eating disorders– are presented and discussed.La capacidad de elección nos proporciona control sobre nuestras vidas y nos ofrece posibilidades de cambio. Sin embargo, para muchas personas no es fácil realizar elecciones efectivas; por ejemplo, los pacientes carecen muchas veces del conocimiento, la habilidad, la asertividad o autoestima necesarias. En esas situaciones, la realidad virtual (RV), una realidad artificial que coloca al sujeto en un espacio generado por el ordenador, puede ser para el terapeuta un recurso decisivo. La experiencia enriquecida y el control total sobre todos sus aspectos transforman la RV en un “entorno fortalecedor”, en el que los pacientes pueden comenzar a explorar y actuar sin sentirse amenazados. El principal objetivo del “Applied Technology for Neuro-Psychology Laboratory” (ATN-P Lab), perteneciente al Instituto Auxologico Italiano, es intentar definir, desarrollar y probar aplicaciones basadas en RV que faciliten el fortalecimiento personal. En este artículo se describe el trabajo que se viene realizando sobre este tema en ese laboratorio. Se presenta y discute, específicamente, el sistema de código abierto denominado “NeuroVR”, así como sus aplicaciones clínicas potenciales sobre los trastornos de ansiedad, la obesidad y los trastornos alimentarios

    Clinical governance of patients with acute coronary syndromes

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    Aims Using the principles of clinical governance, a patient-centred approach intended to promote holistic quality improvement, we designed a prospective, multicentre study in patients with acute coronary syndrome (ACS). We aimed to verify and quantify consecutive inclusion and describe relative and absolute effects of indicators of quality for diagnosis and therapy. Methods and results Administrative codes for invasive coronary angiography and acute myocardial infarction were used to estimate the ACS universe. The ratio between the number of patients included and the estimated ACS universe was the consecutive index. Co-primary quality indicators were timely reperfusion in patients admitted with ST-elevation ACS and optimal medical therapy at discharge. Cox-proportional hazard models for 1-year death with admission and discharge-specific covariates quantified relative risk reductions and adjusted number needed to treat (NNT) absolute risk reductions. Hospital codes tested had a 99.5% sensitivity to identify ACS universe. We estimated that 7344 (95% CI: 6852-7867) ACS patients were admitted and 5107 were enrolled-i.e. a consecutive index of 69.6% (95% CI 64.9-74.5%), which varied from 30.7 to 79.2% across sites. Timely reperfusion was achieved in 22.4% (95% CI: 20.7-24.1%) of patients, was associated with an adjusted hazard ratio (HR) for 1-year death of 0.60 (95% CI: 0.40-0.89) and an adjusted NNT of 65 (95% CI: 44-250). Corresponding values for optimal medical therapy were 70.1% (95% CI: 68.7-71.4%), HR of 0.50 (95% CI: 0.38-0.66), and NNT of 98 (95% CI: 79-145). Conclusion A comprehensive approach to quality for patients with ACS may promote equitable access of care and inform implementation of health care delivery. Registration ClinicalTrials.Gov ID NCT0425553

    Dobutamine stress echocardiography for assessing the role of dynamic intraventricular obstruction in left ventricular ballooning syndrome

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    <p>Abstract</p> <p>Background</p> <p>Dynamic intraventricular obstruction has been observed in patients with left ventricular ballooning syndrome (LVBS) and has been hypothesized as a possible mechanism of the syndrome. The aim of this study was to assess the prevalence and significance of dynamic intraventricular obstruction in patients with LVBS.</p> <p>Methods and Results</p> <p>Dobutamine stress echocardiography was carried out in 22 patients with LVBS (82% apical), all women, aged 68 ± 9 years. At baseline 1 patient had a > 30 mmHg LV gradient; during stress a LV gradient > 30 mm Hg developed in 6/21 patients (28%) and was caused by systolic anterior motion of the mitral valve in the 3 patients with severe gradient (mean 116 ± 29 mmHg), who developed mitral regurgitation and impaired apical wall motion and by obstruction at mid-ventricular level in the other 3 with a moderate gradient (mean 46 ± 16 mmHg). Compared with patients without obstruction those with obstruction had a greater mean septal thickness (11.6 ± .6 vs 9.8. ± 3, p < .01), a higher prevalence of septal hypertrophy (71% vs 7%, p < .005) and a higher peak wall motion score index (1.62 ± .4 vs 1.08 ± .4, p < .01).</p> <p>Conclusion</p> <p>Spontaneous or dobutamine-induced dynamic LV obstruction is documented in 32% of patients with LVBS, is correlated with the presence of septal hypertrophy and may play a role in the development of LVBS in this subset of patients. In those without septal hypertrophy a dynamic obstruction is rarely induced with dobutamine and is unlikely to be a major pathogenetic factor of the syndrome.</p

    Nota dei curatori ed edizione italiana delle opere citate

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    Esposizione della struttura del volume e dei concetti principali dell’opera di Konrad Hesse, negli ambiti dell’interpretazione, dei diritti fondamentali, dello stato di diritto, dei rapporti tra stato e società e del federalismo. Indicazione di alcune scelte di traduzione e indicazione delle edizioni italiane delle opere citate nel volume in lingua tedesca
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