Tissot indicatrices have provided visual measures of local area and isotropy distortions. Here we show how large scale distortions of flexion (bending) and skewness (lopsidedness) can be measured. Area and isotropy distortions depend on the map projection metric, flexion and skewness, which manifest themselves on continental scales, depend on the first derivatives of the metric. We introduce ne...

PURPOSE To compare contrast-enhanced isotropic 3D-GRE-T1WI sequence vs. conventional non-isotropic sequence in terms of image quality, estimated signal-to-noise ratio (eSNR), relative tumor contrast and performance of cervical cancer staging. METHODS This retrospective study was approved by the institutional review board, and informed consent was waived. Seventy-one patients (47 ± 9.4 years),...

The transition from multiple-port to single-port robotic systems in minimally invasive surgery (MIS) procedures has made flexible, dexterous manipulation an essential capability. The requirement that single-port MIS devices span an enclosed surgical workspace through only one access point while avoiding collateral damage to surrounding tissues necessitates the employment of mechanically sophist...

Received 30 January 2004; revised 14 May 2004; accepted 14 June 2004; published 13 August 2004. [1] Shear velocity properties of D00 beneath the central Atlantic Ocean are explored using predominantly European seismic recordings of intermediate and deep focus (>100 km) South American earthquakes. Broadband data are analyzed and, when possible, corrected for upper mantle models of receiver-side ...

Suppose G is a second countable, locally compact, Hausdorff groupoid with a fixed left Haar system. Let G/G denote the orbit space of G and C∗(G) denote the groupoid C∗-algebra. Suppose that the isotropy groups of G are amenable. We show that C∗(G) is CCR if and only if G/G is a T1 topological space and all of the isotropy groups are CCR. We also show that C∗(G) is GCR if and only if G/G is a T...

The question of which quadratic forms become isotropic when extended to the function field of a given form is studied. A formula for the minimum dimension of the minimal isotropic forms associated to such extensions is given, and some consequences thereof are outlined. Especial attention is devoted to function fields of Pfister forms. Here, the relationship between excellence concepts and the i...