When the Crp Ends: A Look at Production Alternatives for Highly Erodible Land in Southern Iowa

This report examines the potential use of land currently under CRP contract in a three-county region in southern Iowa. The objectives are twofold: first, to inventory or assess the productivity and ownership characteristics of CRP land in this region and, second, to predict the possible use for these land resources should the CRP cease to exist. In particular, we are concerned with the impact that changing economic conditions, agricultural policy, and technology might have on this transition. The broader consequences of CRP termination in terms of rural economic activity or environmental quality in the region will be examined indirectly, reflected primarily in terms of changes in farm income, land use, and potential rates of soil erosion.

In vivo model for microbial invasion of tooth root dentinal tubules

ABSTRACT Objective Bacterial penetration of dentinal tubules via exposed dentine can lead to root caries and promote infections of the pulp and root canal system. The aim of this work was to develop a new experimental model for studying bacterial invasion of dentinal tubules within the human oral cavity. Material and Methods Sections of human root dentine were mounted into lower oral appliances that were worn by four human subjects for 15 d. Roots were then fixed, sectioned, stained and examined microscopically for evidence of bacterial invasion. Levels of invasion were expressed as Tubule Invasion Factor (TIF). DNA was extracted from root samples, subjected to polymerase chain reaction amplification of 16S rRNA genes, and invading bacteria were identified by comparison of sequences with GenBank database. Results All root dentine samples with patent tubules showed evidence of bacterial cell invasion (TIF value range from 5.7 to 9.0) to depths of 200 mm or more. A spectrum of Gram-positive and Gram-negative cell morphotypes were visualized, and molecular typing identified species of Granulicatella, Streptococcus, Klebsiella, Enterobacter, Acinetobacter, and Pseudomonas as dentinal tubule residents. Conclusion A novel in vivo model is described, which provides for human root dentine to be efficiently infected by oral microorganisms. A range of bacteria were able to initially invade dentinal tubules within exposed dentine. The model will be useful for testing the effectiveness of antiseptics, irrigants, and potential tubule occluding agents in preventing bacterial invasion of dentine

In vivo model for microbial invasion of tooth root dentinal tubules

Objective Bacterial penetration of dentinal tubules via exposed dentine can lead to root caries and promote infections of the pulp and root canal system. The aim of this work was to develop a new experimental model for studying bacterial invasion of dentinal tubules within the human oral cavity. Material and Methods Sections of human root dentine were mounted into lower oral appliances that were worn by four human subjects for 15 d. Roots were then fixed, sectioned, stained and examined microscopically for evidence of bacterial invasion. Levels of invasion were expressed as Tubule Invasion Factor (TIF). DNA was extracted from root samples, subjected to polymerase chain reaction amplification of 16S rRNA genes, and invading bacteria were identified by comparison of sequences with GenBank database. Results All root dentine samples with patent tubules showed evidence of bacterial cell invasion (TIF value range from 5.7 to 9.0) to depths of 200 mm or more. A spectrum of Gram-positive and Gram-negative cell morphotypes were visualized, and molecular typing identified species of Granulicatella, Streptococcus, Klebsiella, Enterobacter, Acinetobacter, and Pseudomonas as dentinal tubule residents. Conclusion A novel in vivo model is described, which provides for human root dentine to be efficiently infected by oral microorganisms. A range of bacteria were able to initially invade dentinal tubules within exposed dentine. The model will be useful for testing the effectiveness of antiseptics, irrigants, and potential tubule occluding agents in preventing bacterial invasion of dentine

National Performance Benchmarks for Modern Screening Digital Mammography: Update from the Breast Cancer Surveillance Consortium

Purpose To establish performance benchmarks for modern screening digital mammography and assess performance trends over time in U.S. community practice. Materials and Methods This HIPAA-compliant, institutional review board-approved study measured the performance of digital screening mammography interpreted by 359 radiologists across 95 facilities in six Breast Cancer Surveillance Consortium (BCSC) registries. The study included 1 682 504 digital screening mammograms performed between 2007 and 2013 in 792 808 women. Performance measures were calculated according to the American College of Radiology Breast Imaging Reporting and Data System, 5th edition, and were compared with published benchmarks by the BCSC, the National Mammography Database, and performance recommendations by expert opinion. Benchmarks were derived from the distribution of performance metrics across radiologists and were presented as 50th (median), 10th, 25th, 75th, and 90th percentiles, with graphic presentations using smoothed curves. Results Mean screening performance measures were as follows: abnormal interpretation rate (AIR), 11.6 (95% confidence interval [CI]: 11.5, 11.6); cancers detected per 1000 screens, or cancer detection rate (CDR), 5.1 (95% CI: 5.0, 5.2); sensitivity, 86.9% (95% CI: 86.3%, 87.6%); specificity, 88.9% (95% CI: 88.8%, 88.9%); false-negative rate per 1000 screens, 0.8 (95% CI: 0.7, 0.8); positive predictive value (PPV) 1, 4.4% (95% CI: 4.3%, 4.5%); PPV2, 25.6% (95% CI: 25.1%, 26.1%); PPV3, 28.6% (95% CI: 28.0%, 29.3%); cancers stage 0 or 1, 76.9%; minimal cancers, 57.7%; and node-negative invasive cancers, 79.4%. Recommended CDRs were achieved by 92.1% of radiologists in community practice, and 97.1% achieved recommended ranges for sensitivity. Only 59.0% of radiologists achieved recommended AIRs, and only 63.0% achieved recommended levels of specificity. Conclusion The majority of radiologists in the BCSC surpass cancer detection recommendations for screening mammography; however, AIRs continue to be higher than the recommended rate for almost half of radiologists interpreting screening mammograms. © RSNA, 2016 Online supplemental material is available for this article

Breast Tumor Prognostic Characteristics and Biennial vs Annual Mammography, Age, and Menopausal Status

Screening mammography intervals remain under debate in the United States

Dark Spots on Mercury: A Distinctive Low-Reflectance Material and Its Relation to Hollows

Orbital images acquired by the Mercury, Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) spacecraft reveal a distinctive low-reflectance material on the surface of Mercury. Such material occurs in small, isolated, and thin surficial units. We term these features “dark spots.” Dark spots have the lowest average reflectance yet documented on the planet. In every case observed at sufficiently high resolution, dark spots feature hollows at their centers. Not all hollows, however, are surrounded by a dark spot. Dark spots have been found on low-reflectance smooth plains, intercrater plains, heavily cratered terrain, and impact craters at almost all longitudes on Mercury, but they have not been documented on high-reflectance smooth plains material. Dark spots are one of the youngest endogenic features on Mercury, and some postdate craters with distinctive rays. Sulfides may be the phase responsible for the low albedo of dark spot material. We propose that dark spots form during the initial stages of hollow formation, perhaps in a manner similar to intense outgassing events that feature exit velocities in excess of 100 m/s. Such outgassing could contemporaneously produce a depression that constitutes an embryonic hollow. Under this scenario, dark spot material is subsequently removed or modified by regolith gardening or other surface processes on time scales shorter than the lifetime of the central hollow

Immune Response to the West Nile Virus in Aged Non-Human Primates

Background: Risk of encephalitis from West Nile virus (WNV) infection increases dramatically with age. Understanding the basis of this susceptibility requires development of suitable animal models. Here, we investigated the immune response to WNV in old non-human primates. Methodology/Principal Findings: We investigated clinical, immunological and virological correlates of WNV infection in aging non-human primates. Aged (17-30yrs) and adult (6-9yrs) Rhesus macaques (RM) were challenged with WNV in the presence or the absence of the mosquito salivary gland extract (SGE) to approximate natural infection. None of the 26 animals exhibited clinical signs of the disease. Quantitative PCR suggested discrete and short-lived viremia, but infectious virus was never isolated. There was markedly increased, age-independent, proliferation of CD3- non-B cells, followed by Bcell proliferation, which correlated to the loss of detectable WNV genomes. Moreover, animals primed with mosquito salivary gland extract exhibited reduced circulating WNV RNA. While we found the expected age-associated reduction in T cell proliferation, adaptive immunity did not correlate with infection outcome. That was further confirmed in a cohort of thymectomized and/or CD8 T-cell depleted Cynomolgus macaques (CM; N = 15), who also failed to develop WNV disease. Conclusions/significance: Results are consistent with strong and age-independent innate resistance of macaques against WNV challenge. This animal model is therefore not suitable for vaccine and therapeutic testing against WNV. However, understanding the basis of their innate resistance against WNV in macaques could provide helpful clues to improve anti- WNV protection of older adults. © 2010 Wertheimer et al

Interference filters as nonlinear decision-making elements for three-spot pattern recognition and associative memories

Simple patterns consisting of three spots (V and Γ) have been recognized by dividing, shifting, and recombining beams onto bistable ZnS interference filters. This experiment demonstrates AND-gate operation, cascading, and a moderate amount of parallelism, but a laser power of several watts was required and the response times were several milliseconds. An associative memory for fingerprint identification has been constructed using a VanderLugt correlator and an interference filter as a reflective thresholding device