In vivo imaging of amyloid burden with positron emission tomography (PET) provides a means for studying the pathophysiology of Alzheimer's and related diseases. Measurement of subtle changes in amyloid burden requires quantitative analysis of image data. Reliable quantitative analysis of amyloid PET scans acquired at multiple sites and over time requires rigorous standardization of acquisition ...

Our goal was to develop a system that would allow us to recreate live patient arterial pathology by using an industrial technique known as stereolithography (or rapid prototyping). In industry, drawings rendered into dicom files can be exported to a computer programmed to drive various industrial tools. Those tools then make a 3D structure shown by the original drawings. We manipulated CT scan ...

Nowadays many MRI scans can give 3D volume data with different contrasts, but the observers may want to view various contrasts in the same 3D volume. The conventional 2D medical fusion methods can only fuse the 3D volume data layer by layer, which may lead to the loss of interframe correlative information. In this paper, a novel 3D medical volume fusion method based on 3D band limited shearlet ...

Within an effective field theory framework we compute the most general structure of the one-loop corrections to the 4D gauge couplings in one-and two-dimensional orbifold compacti-fications with non-vanishing constant gauge background (Wilson lines). Although such models are non-renormalisable, we keep the analysis general by considering the one-loop corrections in three regularisation schemes:...

The problem of constructing a quantum theory of gravity has been tackled with very different strategies. An attractive possibility is that of encoding all possible space-times as specific Feynman diagrams of a suitable field theory as it happens for the matrix model formulation of two-dimensional quantum gravity (see for example [1] and references therein). In the perturbative approach to the m...

8 we have found critical exponents very similar to those of the pure Ising model. We have found that the value of the critical exponents show that for lattices up to V = 32 4 the system, for p = 0:3, is not described by the mean eld theory, as one might have believed. Moreover the critical exponents that we have found are very near to those of the pure percolation. A possible explanation would ...

The Theory of Knowledge Creation generally suggests that tacit and explicit knowledge are converted through the four modes known as the SECI Model (Nonaka 1991; Nonaka & Takeuchi 1995). In applications development, the knowledge conversions are mobilized through the use of tools (video conference, development editor) and practices (code review, design patterns, pair programming) (Henninger 1997...

This paper reports two speci c improvements in the nite-dimensional nonlinear dynamical modeling of marine thrusters. Previously reported four-quadrant models have employed airfoil theory considering only axial uid ow and using sinusoidal lift/drag curves. First, we present a thruster model incorporating the e ects of rotational uid velocity and inertia on thruster response. Second, we report a...

New medical imaging devices, such as the CT scanner, have begun to challenge traditional role relations among radiologists and radiological technologists. Under some conditions, these technologies may actually alter the organizational and occupational structure of radiological work. However, current theories of technology and organizational form are insensitive to the potential number of struct...