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Radon transforms are integral operators widely used in seismic exploration for multiple attenuation, velocity analysis and data interpolation. A reasonable assumption about the Radon transform applied to seismic images is sparseness, where the image energy focuses into clusters in the Radon model space. In this paper we apply the Weak Orthogonal Matching Pursuit framework (WOMP) to exploit sparseness and implement a High Resolution Radon Transform: in particular, we introduce a new automatic selection criterion for the Weak Orthogonal Matching Pursuit algorithm based on the physical model underlying the problem (called GeOMP). Results on real data prove the effectiveness of the method over general purpose selection criteria in terms of both reconstruction quality and decreased computational cost.

Background The aim of this paper was to compare the use of two different commercially available vascular closure devices (VCD), Angioseal VIP® (St. Jude Medical, St. Paul, MN, USA) and StarClose SE (Abbott Laboratories, Abbott Park, IL, USA). Methods From January 2010 to January 2012, 347 patient underwent retrograde femoral arterial puncture for different interventional procedures (angioplasty, stenting, embolization for bleeding, fibrinolysis for ischemia and chemoembolization). Hemostasis was achieved by deployment of an Angioseal VIP® (N.=184) or StarClose SE® (N.=163). In 94 cases, the retrograde femoral access was bilateral and managed with two StarClose SE devices (N.=53) or an Angioseal VIP® plus a StarClose SE® (N.=41). Results Technical success was obtained in 95.1% (330/347) of patients. Overall time to hemostasis (TTH) and time to ambulation (TTA) were 5,5±1,5 min (range 3-8 min) and 6±2.5 hr (range 2-9 hours) respectively. No statistical significative difference (P>0.05) were appreciable between to groups for both TTH and TTA: Angioseal VIP® TTH was 5.3±1.4 min and StarClose SE® TTH was 5.6±1.6 min; Angioseal VIP® TTA was 5.9±1.8 hr and StarClose SE® TTA was 6.1±1.9 hr. VAS scores result underline a mild difference between two devices. Angioseal VIP® patients experience a mild to moderate pain within the first 3 minutes from the deployment. Whereas StarClose SE® patients still experience pain at 5 minutes from deployment. The device failure rate was 4.9% (17 cases) and included 13 minor complications and 4 major complications. Minor complications (3.75%) occurred during the initial phase and consisted in recurrent wound bleeding (N.=5 StarClose SE®; N.=4 Angioseal VIP®) treated with manual compression, and hematoma (N.=2 StarClose SE®; N.=2 Angioseal VIP®) that solved spontaneously. The 4 major complications (1,15%) were: 1 Angioseal-related common femoral artery (CFA) obstruction treated with surgical bypass from the CFA to the superficial femoral artery; 1 Angioseal-related CFA dissection solved with surgery; 1 Angioseal-related embolization of the deep femoral artery partially treated with localized fibrinolysis; 1 StarClose-related pseudoaneurysm treated with manual compression. Conclusions Both Angioseal VIP® and StarClose SE® systems can be considered safe and effective in providing hemostasis following a variety of interventional vascular procedures.

The increased limitations to both NOx and soot emissions have pushed engine researchers to rediscover gasoline engines. Among the many technologies and strategies, gasoline direct injection plays a key-role for improving fuel economy and engine performance. The paper aims to investigate an extremely complex task such as the idle operating engine condition when the engine runs at very low engine speeds and low engine loads and during the warm-up. Due to the low injection pressure and to the null contribution of the turbocharger, the engine condition is far from the standard points of investigation. Taking into account the warm-up engine condition, the analyses are performed with a temperature of the coolant of 50°C. The paper reports part of a combined numerical and experimental synergic activity aiming at the understanding of the physics of spray/wall interaction within the combustion chamber and particular care is used for air/fuel mixing and the combustion process analyses. In order to properly describe the engine condition, different injection strategies are investigated. Late and early injection strategies are deeply analyzed and compared in terms of combustion stability and pollutant emissions. UV-visible imaging and spectral measurements are carried out in real engine with wide optical accesses... Measurements are performed in the optically accessible combustion chamber realized by modifying a real engine. The cylinder head was modified in order to allow in the fourth cylinder the visualization of the fuel injection and the combustion process with high spatial and temporal resolution. The 3D-CFD engine simulations are reproduced by means the commercial code Star-CD. Due to the warm-up condition and the many physical sub-models a numerical methodology is implemented and particular care is used to boundaries conditions analyses. CFD analysis is used to find a possible explanation of the high cycle to cycle variability. The experimental and numerical comparisons, in terms fuel mixing and front flame propagation, give an explanation of the idle condition.

In this paper, we present a new approach for face recognition that is robust against both poorly defined and poorly aligned training and testing data even with few training samples. Working in the conventional feature space yielded by the Fisher's Linear Discriminant analysis, it uses a recent algorithm for sparse representation, namely k-LiMapS, as general classification criterion. Such a technique performs a local l0 pseudo-norm minimization by iterating suitable parametric nonlinear mappings. Thanks to its particular search strategy, it is very fast and able to discriminate among separated classes lying in the low-dimension Fisherspace. Experiments are carried out on the FRGC version 2.0 database showing good classification capability even when compared with the state-of-the-art l1 norm-based sparse representation classifier (SRC).

A lesao tecidual causada por procedimentos cirurgicos, e a consequente reacao inflamatoria decorrente deste processo, resultam em condicoes dolorosas no periodo pos-operatorio. A dor pos-operatoria de uma cesariana costuma retardar o retorno das puerperas as suas atividades de vida diaria proporcionando-lhes diminuicao da mobilidade e consequentemente limitacoes. A Estimulacao Eletrica Nervosa Transcutânea (EENT) vem se apresentando, nos ultimos anos, como um importante instrumento clinico no tratamento da dor. Objetivo: Avaliar o efeito da aplicacao da EENT convencional para o alivio da dor em puerperas pos-cesariana. Metodo: Trata-se de uma pesquisa do tipo quantitativa de carater experimental. A amostra constou de 20 puerperas, submetidas a cirurgia de cesariana, estando no puerperio imediato, apresentando dor no local da incisao cirurgica. Para realizacao da coleta, foi utilizado um questionario de Limitacao Funcional, um aparelho de Eletroestimulacao Nervosa Transcutânea (EENT), e a Escala Visual Analogica (EVA) como meio de mensurar a dor antes e apos a eletroestimulacao. Resultados: Houve uma diferenca estatisticamente significante entre as intensidades da dor antes e apos o uso da EENT, onde a media encontrada antes da aplicacao foi 6,35 e depois da aplicacao 2,9. As principais limitacoes encontradas em consequencia da dor pos-operatoria foram para as funcoes de sentar e levantar da cama (90%), ficar na posicao de decubito lateral (90%) e tossir (85%). Conclusao: A EENT mostrou-se ser eficaz, pois reduziu significativamente os escores da dor causados pela lesao tecidual.