Radiographic Image Enhancement by Wiener Decorrelation

The primary focus of the application of image processing to radiography is the problem of segmentation. The general segmentation problem has been attacked on a broad front [1, 2], and thresholding, in particular, is a popular method [1, 3-6]. Unfortunately, geometric unsharpness destroys the crisp edges needed for unambiguous decisions, and this difficulty can be considered a problem in filtering in which the object is to devise a high-pass (sharpening) filter. This approach has been studied for more than 20 years [7-13]

Argonne National Laboratory Reports

DISPL is a software package for solving some second-order nonlinear systems of partial differential equations including parabolic, elliptic, hyperbolic, and some mixed types such as parabolic-elliptic equations. Fairly general nonlinear boundary conditions are allowed as well as interface conditions for problems in an inhomogeneous media. The spatial domain is one- or two-dimensional with Cartesian, cylindrical, or spherical (in one dimension only) geometry. The numerical method is based on the use of Galerkin's procedure combined with the use of B-splines in order to reduce the system of PDE's to a system of ODE's. The latter system is then solved with a sophisticated ODE software package. Software features include extensive dump/restart facilities, free format input, moderate printed output capability, dynamic storage allocation, and three graphics packages

Hybrid time-domain and continuous-wave diffuse optical tomography instrument with concurrent, clinical magnetic resonance imaging for breast cancer imaging

Diffuse optical tomography has demonstrated significant potential for clinical utility in the diagnosis and prognosis of breast cancer, and its use in combination with other structural imaging modalities improves lesion localization and the quantification of functional tissue properties. Here, we introduce a hybrid diffuse optical imaging system that operates concurrently with magnetic resonance imaging (MRI) in the imaging suite, utilizing commercially available MR surface coils. The instrument acquires both continuous-wave and time-domain diffuse optical data in the parallel-plate geometry, permitting both absolute assignment of tissue optical properties and three-dimensional tomography; moreover, the instrument is designed to incorporate diffuse correlation spectroscopic measurements for probing tissue blood flow. The instrument is described in detail here. Image reconstructions of a tissue phantom are presented as an initial indicator of the system’s ability to accurately reconstruct optical properties and the concrete benefits of the spatial constraints provided by concurrent MRI. Last, we briefly discuss how various data combinations that the instrument could facilitate, including tissue perfusion, can enable more comprehensive assessment of lesion physiology

Beyond belief: Strategic taboos and organizational identity in strategic agenda setting

A comprehensive strategic agenda matters for fundamental strategic change. Our study seeks to explore and theorize how organizational identity beliefs influence the judgment of strategic actors when setting an organization’s strategic agenda. We offer the notion of “strategic taboo” as those strategic options initially disqualified and deemed inconsistent with the organizational identity beliefs of strategic actors. Our study is concerned with how strategic actors confront strategic taboos in the process of setting an organization’s strategic agenda. Based on a revelatory inductive case study, we find that strategic actors engage in assessing the concordance of the strategic taboos with organizational identity beliefs and, more specifically, that they focus on key identity elements (philosophy; priorities; practices) when doing so. We develop a typology of three reinterpretation practices that are each concerned with a key identity element. While contextualizing assesses the potential concordance of a strategic taboo with an organization’s overall philosophy and purpose, instrumentalizing assesses such concordance with respect to what actors deem an organization’s priorities to be. Finally, normalizing explores concordance with respect to compatibility and fit with the organization’s practices. We suggest that assessing concordance of a strategic taboo with identity elements consists in reinterpreting collective identity beliefs in ways that make them consistent with what organizational actors deem the right course of action. This article discusses the implications for theory and research on strategic agenda setting, strategic change, a practice-based perspective on strategy, and on organizational identity. © The Author(s) 2014

Liver Fibrosis Linked to Cognitive Performance in HIV and Hepatitis C

Since HIV impairs gut barriers to pathogens, HIV-infected adults may be vulnerable to Minimal Hepatic Encephalopathy (MHE) in the absence of cirrhosis

Cervical Screening within HIV Care: Findings from an HIV-Positive Cohort in Ukraine

HIV-positive women have an increased risk of invasive cervical cancer but cytologic screening is effective in reducing incidence. Little is known about cervical screening coverage or the prevalence of abnormal cytology among HIV-positive women in Ukraine, which has the most severe HIV epidemic in Europe

HIV Tropism and Decreased Risk of Breast Cancer

During the first two decades of the U.S. AIDS epidemic, and unlike some malignancies, breast cancer risk was significantly lower for women with human immunodeficiency virus (HIV) infection compared to the general population. This deficit in HIV-associated breast cancer could not be attributed to differences in survival, immune deficiency, childbearing or other breast cancer risk factors. HIV infects mononuclear immune cells by binding to the CD4 molecule and to CCR5 or CXCR4 chemokine coreceptors. Neoplastic breast cells commonly express CXCR4 but not CCR5. In vitro, binding HIV envelope protein to CXCR4 has been shown to induce apoptosis of neoplastic breast cells. Based on these observations, we hypothesized that breast cancer risk would be lower among women with CXCR4-tropic HIV infection.We conducted a breast cancer nested case-control study among women who participated in the WIHS and HERS HIV cohort studies with longitudinally collected risk factor data and plasma. Cases were HIV-infected women (mean age 46 years) who had stored plasma collected within 24 months of breast cancer diagnosis and an HIV viral load≥500 copies/mL. Three HIV-infected control women, without breast cancer, were matched to each case based on age and plasma collection date. CXCR4-tropism was determined by a phenotypic tropism assay. Odds ratios (OR) and 95% confidence intervals (CI) for breast cancer were estimated by exact conditional logistic regression. Two (9%) of 23 breast cancer cases had CXCR4-tropic HIV, compared to 19 (28%) of 69 matched controls. Breast cancer risk was significantly and independently reduced with CXCR4 tropism (adjusted odds ratio, 0.10, 95% CI 0.002-0.84) and with menopause (adjusted odds ratio, 0.08, 95% CI 0.001-0.83). Adjustment for CD4+ cell count, HIV viral load, and use of antiretroviral therapy did not attenuate the association between infection with CXCR4-tropic HIV and breast cancer.Low breast cancer risk with HIV is specifically linked to CXCR4-using variants of HIV. These variants are thought to exclusively bind to and signal through a receptor that is commonly expressed on hyperplastic and neoplastic breast duct cells. Additional studies are needed to confirm these observations and to understand how CXCR4 might reduce breast cancer risk

On Radio Detection of Ultra-High Energy Neutrinos in Antarctic Ice

Interactions of ultrahigh energy neutrinos of cosmological origin in large volumes of dense, radio-transparent media can be detected via coherent Cherenkov emission from accompanying electromagnetic showers. Antarctic ice meets the requirements for an efficient detection medium for a radio frequency neutrino telescope. We carefully estimate the sensitivity of realistic antennas embedded deep in the ice to 100 MHz - 1 GHz signals generated by predicted neutrino fluxes from active galactic nuclei. Our main conclusion is that a {\it single radio receiver} can probe a $\sim 1$ ${\rm km}^3$ volume for events with primary energy near 2 PeV and that the total number of events registered would be roughly 200 to 400 ${\rm year}^{-1}$ in our most conservative estimate. An array of such receivers would increase sensitivity dramatically. A radio neutrino telescope could directly observe and test our understanding of the most powerful particle accelerators in the universe, simultaneously testing the standard theory of particle physics at unprecedented energies.Comment: 45 pages, 21 figures, uuencoded, gzipped, submitted to Phys. Rev. D, also available at http://poincare.math.ukans.edu/~frichter/radio.html (Shading in Figure 21 fixed

Cohort profile: The women’s interagency HIV study (WIHS)

Why was the cohort set up? The National Institutes of Health established the Women’s Interagency HIV Study (WIHS) in 1993 to study the impact and progression of HIV infection among women in response to the rising number of AIDS cases and the relative paucity of clinical, behavioural and epidemiological data in this population. Women now comprise more than 50% of people with HIV (PWH) worldwide.1 The WIHS is the largest and oldest ongoing prospective cohort study of women with and at risk for HIV infection in the world, and remains the leading study to document the experience of women with HIV (WWH) in the United States