Recommended Core Measures for Evaluating the Patient-Centered Medical Home: Cost, Utilization, and Clinical Quality

Outlines the process of the Patient-Centered Medical Home Evaluators' Collaborative for identifying core standardized measures and their recommended principles and measures for evaluating cost and utilization and clinical quality

A taxonomy of parallel sorting

TR 84-601In this paper, we propose a taxonomy of parallel sorting that includes a broad range of array and file sorting algorithms. We analyze the evolution of research on parallel sorting, from the earliest sorting networks to the shared memory algorithms and the VLSI sorters. In the context of sorting networks, we describe two fundamental parallel merging schemes - the odd-even and the bitonic merge. Sorting algorithms have been derived from these merging algorithms for parallel computers where processors communicate through interconnection networks such as the perfect shuffle, the mesh and a number of other sparse networks. After describing the network sorting algorithms, we show that, with a shared memory model of parallel computation, faster algorithms have been derived from parallel enumeration sorting schemes, where keys are first ranked and then rearranged according to their rank

Realtime Photoacoustic Microscopy of Murine Cardiovascular Dynamics

Non-invasive visualization of cardiovascular dynamics in small animals is challenging due to their rapid heart-rates. We present a realtime photoacoustic imaging system consisting of a 30-MHz ultrasound array transducer, receive electronics, a high-repetition-rate laser, and a multicore-computer, and demonstrate its ability to image optically-absorbing structures of the beating hearts of young athymic nude mice at rates of ~50 frames per second with 100 µm×25 µm spatial resolution. To our knowledge this is the first report of realtime photoacoustic imaging of physiological dynamics

Fast 3-D photoacoustic imaging in vivo with a high frequency ultrasound array toward clinical applications

We present an in vivo reflection-mode photoacoustic microscopy system that performs B-scan imaging at 50 Hz with realtime beamforming and 3-D imaging of 166 B-scan frames at 1 Hz with post-beamforming. To our knowledge, this speed is currently the fastest in high frequency photoacoustic imaging. In addition, with a custom fiber based light delivery system, the imaging device is capable of performing handheld operation. Software for image processing and display with clinically user-friendly graphic user interface (GUI) is developed. The system has axial, lateral, and elevational resolutions of 25, 70, and 200 μm, respectively, and can image 3 mm deep in scattering biological tissue. Volumetric images of subcutaneous vasculature in murine are demonstrated in vivo. The system is anticipated to have potential clinical applications in skin melanoma detection due to its unique ability to image in realtime and to image anatomical sites inaccessible to other imaging systems

A 3-D High-Frequency Array Based 16 Channel Photoacoustic Microscopy System for In Vivo Micro-Vascular Imaging

This paper discusses the design of a novel photoacoustic microscopy imaging system with promise for studying the structure of tissue microvasculature for applications in visualizing angiogenesis. A new 16 channel analog and digital high-frequency array based photoacoustic microscopy system (PAM) was developed using an Nd: YLF pumped tunable dye laser, a 30 MHz piezo composite linear array transducer, and a custom multichannel receiver electronics system. Using offline delay and sum beam- forming and beamsteering, phantom images were obtained from a 6 µm carbon fiber in water at a depth of 8 mm. The measured -6 dB lateral and axial spatial resolution of the system was 100 ± 5 µm and 45 ± 5 µm, respectively. The dynamic focusing capability of the system was demonstrated by imaging a composite carbon fiber matrix through a 12.5 mm imaging depth. Next, 2-D in vivo images were formed of vessels around 100 µm in diameter in the human hand. Three-dimensional in vivo images were also formed of micro-vessels 3 mm below the surface of the skin in two Sprague Dawley rats

Fast 3-D dark-field reflection-mode photoacoustic microscopy in vivo with a 30-MHz ultrasound linear array

We present an in vivo dark-field reflection-mode photoacoustic microscopy system that performs cross-sectional (B-scan) imaging at 50Hz with real-time beamforming and 3-D imaging consisting of 166 B-scan frames at 1Hz with postbeamforming. To our knowledge, this speed is currently the fastest in photoacoustic imaging. A custom-designed light delivery system is integrated with a 30-MHz ultrasound linear array to realize dark-field reflection-mode imaging. Linear mechanical scanning of the array produces 3-D images. The system has axial, lateral, and elevational resolutions of 25, 70, and 200μm, respectively, and can image 3mm deep in scattering biological tissues. Volumetric images of subcutaneous vasculature in rats are demonstrated in vivo. Fast 3-D photoacoustic microscopy is anticipated to facilitate applications of photoacoustic imaging in biomedical studies that involve dynamics and clinical procedures that demand immediate diagnosis

Imaging microvascular dynamics noninvasively with realtime photoacoustic microscopy

A realtime photoacoustic microscopy system consisting of a high-repetition rate pulsed laser, high-frequency (30 MHz) ultrasound array transducer, and realtime receiving system was used to visualize microvessels pulsations over a cardiac cycle. The system offers 100 μm lateral spatial resolution, 25 µm axial spatial resolution, and can image at a rate of 83 frames per second. The system shows promise for visualizing time-varying processes in the microvasculature

Red fluorescence of the triplefin Tripterygion delaisi is increasingly visible against background light with increasing depth

The light environment in water bodies changes with depth due to the absorption of short and long wavelengths. Below 10 m depth, red wavelengths are almost completely absent rendering any red-reflecting animal dark and achromatic. However, fluorescence may produce red coloration even when red light is not available for reflection. A large number of marine taxa including over 270 fish species are known to produce red fluorescence, yet it is unclear under which natural light environment fluorescence contributes perceptively to their colours. To address this question we: (i) characterized the visual system of Tripterygion delaisi, which possesses fluorescent irides, (ii) separated the colour of the irides into its reflectance and fluorescence components and (iii) combined these data with field measurements of the ambient light environment to calculate depth-dependent perceptual chromatic and achromatic contrasts using visual modelling. We found that triplefins have cones with at least three different spectral sensitivities, including differences between the two members of the double cones, giving them the potential for trichromatic colour vision. We also show that fluorescence contributes increasingly to the radiance of the irides with increasing depth. Our results support the potential functionality of red fluorescence, including communicative roles such as species and sex identity, and non-communicative roles such as camouflage