BACKGROUND Structural pathology may be present in joints without radiographic evidence of osteoarthritis (OA). Ultrasound is a sensitive tool for early detection of osteophytes. Our aim was to explore whether ultrasound-detected osteophytes (in radiographically and clinically normal finger joints) predicted the development of radiographic and clinical hand OA 5 years later. METHODS We include...

up to 19% of breast malignancies may be missed by conventional imaging techniques, especially when they are concurrent or co-located with other benign lesions. however, more sensitive techniques, such as magnetic resonance imaging (mri), are often too expensive for routine use in developing countries. contrast-enhanced, dual-energy digital mammography (cesm) is a recently introduced imaging mod...

We report on the observation and application of near-field speckles with a laboratory x-ray source. The detection of speckles is possible thanks to the enhanced brilliance properties of the used liquid-metal-jet source, and opens the way to a range of new applications in laboratory-based coherent x-ray imaging. Here, we use the speckle pattern for multimodal imaging of demonstrator objects. Mor...

Given a spacelike 2-surface Σ in a spacetime N and a constant future timelike unit vector T0 in R 3,1 , we derive upper and lower estimates of Wang-Yau quasilocal energy E(Σ, X, T0) for a given isometric embedding X of Σ into a flat 3-slice in R 3,1 . The quantity E(Σ, X, T0) itself depends on the choice of X , however the infimum of E(Σ, X, T0) over T0 does not. In particular, when Σ lies in a...

Objective(s). The major challenge encountered to decrease the milliamperes (mA) level in X-ray imaging systems is the quantum noise phenomena. This investigation evaluated dose exposure and image resolution of a low dose X-ray imaging (LDXI) prototype comprising a low mA X-ray source and a novel microlens-based sensor relative to current imaging technologies. Study Design. A LDXI in static (gro...

A new tangential two-dimensional soft x-ray imaging system (SXRIS) is being designed to examine the edge island structure in the lower X-point region of DIII-D. Plasma shielding and/or amplification of the calculated vacuum islands may play a role in the suppression of edge-localized modes via resonant magnetic perturbations (RMPs). The SXRIS is intended to improve the understanding of three-di...

Phase-contrast x-ray imaging is a promising improvement of conventional absorption-based mammography for early tumor detection. This potential has been demonstrated recently, utilizing structured gratings to obtain differential phase and dark-field scattering images. However, the inherently anisotropic imaging sensitivity of the proposed mono-directional approach yields only insufficient diagno...

Wide angle x-ray scattering (WAXS) from oriented lipid multilayers is used to examine liquid-ordered (Lo)/liquid-disordered (Ld) phase coexistence in the system 1,2-dioleoyl-sn-glycero-3-phosphocholine/1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol (DOPC/DPPC/Chol), which is a model for the outer leaflet of the animal cell plasma membrane. Using the method of analysis developed in the ...

PURPOSE High-spatial-resolution x-ray imaging in the few-ten-keV range is becoming increasingly important in several applications, such as small-animal imaging and phase-contrast imaging. The detector properties critically influence the quality of such imaging. Here the authors present a quantitative comparison of scintillator-based detectors for this energy range and at high spatial frequencie...

An extension of the traditional modulation transfer function (MTF), the detective MTF, is proposed for the evaluation of the resolution of X-ray imaging detectors with non-uniform efficiency on the scale of individual detector elements. The dMTF is shown to give a better representation than does the MTF of the improved resolution reported when the readout of the detectors is enhanced.