600 research outputs found
Splenic Artery Pseudoaneurysms: The Role of ce-CT for Diagnosis and Treatment Planning
Splenic artery pseudoaneurysm (PSA) is a contained vascular wall lesion associated with a high mortality rate, generally related to pancreatitis, trauma, malignancy, iatrogenic injury, and segmental arterial mediolysis. Computed tomography angiography allows us to visualize the vascular anatomy, differentiate a PSA from an aneurysm, and provide adequate information for endovascular/surgical treatment. The present review reports on the main state-of-the-art splenic artery PSA diagnosis, differentiating between the pros and cons of the imaging methods and about the endovascular treatment
A new geometric invariant on initial data for Einstein equations
For a given asymptotically flat initial data set for Einstein equations a new
geometric invariant is constructed. This invariant measure the departure of the
data set from the stationary regime, it vanishes if and only if the data is
stationary. In vacuum, it can be interpreted as a measure of the total amount
of radiation contained in the data.Comment: 5 pages. Important corrections regarding the generalization to the
non-time symmetric cas
Solutions of special asymptotics to the Einstein constraint equations
We construct solutions with prescribed asymptotics to the Einstein constraint
equations using a cut-off technique. Moreover, we give various examples of
vacuum asymptotically flat manifolds whose center of mass and angular momentum
are ill-defined.Comment: 13 pages; the error in Lemma 3.5 fixed and typos corrected; to appear
in Class. Quantum Gra
Attention modulates psychophysical and electrophysiological response to visual texture segmentation in humans
none5noTo investigate whether processing underlying texture segmentation is limited when texture is not attended, we measured orientation discrimination accuracy and visual evoked potentials (VEPs) while a texture bar was cyclically alternated with a uniform texture, either attended or not. Orientation discrimination was maximum when the bar was explicitly attended, above threshold when implicitly attended, and fell to just chance when unattended, suggesting that orientation discrimination based on grouping of elements along texture boundary requires explicit attention. We analyzed tsVEPs (variations in VEP amplitude obtained by algebraic of uniform-texture from segmented-texture VEPs) elicited by the texture boundary orientation discrimination task. When texture was unattended, tsVEPs still reflected local texture segregation. We found larger amplitudes of early tsVEP components (N75, P100, N150, N200) when texture boundary was parallel to texture elements, indicating a saliency effect, perhaps at V1 level. This effect was modulated by attention, disappearing when the texture was not attended, a result indicating that attention facilitates grouping by collinearity in the direction of the texture boundary.openCasco, C; Grieco, A; Campana, G; CORVINO M., P; Caputo, GIOVANNI BATTISTACasco, C; Grieco, A; Campana, G; CORVINO M., P; Caputo, GIOVANNI BATTIST
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