While a variety of fundamental differences are known to separate two-dimensional (2D) and three-dimensional (3D) fluid flows, it is not well understood how they are related. Conventionally, dimensional reduction is justified by an a priori geometrical framework; i.e., 2D flows occur under some geometrical constraint such as shallowness. However, deeper inquiry into 3D flow often finds the prese...

UNLABELLED Quantitative PET with (15)O provides absolute values for cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral metabolic rate of oxygen (CMRO(2)), and oxygen extraction fraction (OEF), which are used for assessment of brain pathophysiology. Absolute quantification relies on physically accurate measurement, which, thus far, has been achieved by 2-dimensional PET (2D PET), t...

Four-dimensional computed tomography (4D CT) is a dynamic volume imaging system of moving organs with an image quality comparable to that of conventional CT. 4D CT will be realized by several technical breakthroughs for dynamic cone-beam CT: (1) a large-area two-dimensional (2D) detector; (2) high-speed data transfer system; (3) reconstruction algorithms; (4) ultra-high-speed reconstruction com...

Lithography as developed for IC device fabrication is a high volume high accuracy patterning technology with strong 2 dimensional (2D) characteristics. This 2D nature makes it a challenge to integrate this technology in a 3 dimensional (3D) manufacturing environment. This article addresses the performance of a waferstepper (ASML PAS5000) in several 3D processes ranging form waferbonding and thi...

In order to investigate characteristics of the "structure from motion" in noise, we compared performances of recovering a three-dimensional structure from motion (3D condition) with those of recovering a two-dimensional structure (2D condition). In addition, we adopted a statistical efficiency approach to analyze the results. We conducted two experiments where we presented to observers a pair o...

Most commonly used methods for three-dimensional (3D) fluorescence microscopy make use of sectioning techniques that require that the object be physically scanned in a series of two-dimensional (2D) sections along the z axis. The main drawback in these approaches is the need for these sequential 2D scans. An alternative approach to fluorescence imaging in three dimensions has been developed tha...

Two-dimensional nuclear magnetic resonance (2D NMR) provides one of the foremost contemporary tools available for the elucidation of molecular structure, function, and dynamics. Execution of a 2D NMR experiment generally involves scanning a series of time-domain signals S(t(2)), as a function of a t(1) time variable which undergoes parametric incrementation throughout independent experiments. V...

We present a novel experimental scheme for two-dimensional fluorescence-detected coherent spectroscopy (2D-FDCS) using a non-collinear beam geometry with the aid of "confocal imaging" of dynamic (population) grating and 27-step phase-cycling to extract the signal. This arrangement obviates the need for distinct experimental designs for previously developed transmission detected non-collinear tw...

Incompressible, inviscid, irrotational, unsteady flows with circulation Gamma around a distorted toroidal bubble are considered. A general variational principle that determines the evolution of the bubble shape is formulated. For a two-dimensional (2D) cavity with a constant area A, exact pseudodifferential equations of motion are derived, based on variables that determine a conformal mapping o...

The influence of twoand three-dimensional filming procedures on the calculation of soccer instep kicking kinematics was examined in this study. The knee angular velocity calculated three-dimensionally was compared with the data obtained from the following two procedures: 1. the angular velocity vector was computed as a perpendicular component to the sagittal plane (2D projection); 2. the angula...