A performance comparison between block interleaved and helically interleaved concatenated coding systems

The performance (bit-error rate vs. signal-to-noise ratio) of two different interleaving systems, block interleaving and the newer helical interleaving are compared. Both systems are studied with and without error forecasting. Without error forecasting, the two systems have identical performance. When error forecasting is used with shallow interleaving, helical interleaving gains, but less than 0.05 dB, over block interleaving. For higher interleaving depth, the systems have almost indistinguishable performance

Abdominopelvic Splenosis—An Unusual Cause of Tenesmus

Splenosis is a rare condition defined as seeding and autotransplantation of splenic tissue, typically after blunt abdominal trauma (e.g. from road traffic collision). Sites of splenosis ranging from intrathoracic to intrapelvic have been reported, and symptoms vary greatly depending on the site and size of lesions. We present the use of Tc-99m sulphur colloid SPECT/CT in diagnosing a case of multiple abdominopelvic splenosis as the cause of new-onset tenesmus and constipation, which was initially thought to be due to colorectal malignancy, 47 years following the initial abdominal trauma

Node synchronization schemes for the Big Viterbi Decoder

The Big Viterbi Decoder (BVD), currently under development for the DSN, includes three separate algorithms to acquire and maintain node and frame synchronization. The first measures the number of decoded bits between two consecutive renormalization operations (renorm rate), the second detects the presence of the frame marker in the decoded bit stream (bit correlation), while the third searches for an encoded version of the frame marker in the encoded input stream (symbol correlation). A detailed account of the operation is given, as well as performance comparison, of the three methods

Automatic photointerpretation for land use management in Minnesota

There are no author-identified significant results in this report

Monte Carlo simulations of liquid crystals near rough walls

The effect of surface roughness on the structure of liquid crystalline fluids near solid substrates is studied by Monte Carlo simulations. The liquid crystal is modeled as a fluid of soft ellipsoidal molecules and the substrate is modeled as a hard wall that excludes the centers of mass of the fluid molecules. Surface roughness is introduced by embedding a number of molecules with random positions and orientations within the wall. It is found that the density and order near the wall are reduced as the wall becomes rougher, i.e., the number of embedded molecules is increased). Anchoring coefficients are determined from fluctuations in the reciprocal space order tensor. It is found that the anchoring strength decreases with increasing surface roughness

Providing Preventive Oral Health Care to Infants and Young Children in Women, Infants, and Children (WIC), Early Head Start, and Primary Care Settings

This report focuses on seven oral health programs that provide preventive oral health care to young children (infants, toddlers, and children up to 5 years old) in Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), Early Head Start (EHS), and primary care settings. All of the programs strive to increase access to preventive oral health care by integrating dental services into primary care settings, WIC clinics, or EHS centers. These programs also rely on primary care providers (physicians, nurses, medical assistants, etc.) or new types of dental hygienists who can practice in community settings to deliver preventive oral health services. Two additional reports in this series describe the remaining programs that provide care in non-dental settings and programs designed to specifically address socioeconomic, cultural, and geographic barriers to preventive oral health care.The findings from the EAs of these programs are synthesized to highlight diverse and innovative strategies that are utilized to provide preventive oral health care in primary care settings, WIC clinics, or EHS centers. These strategies have potential for rigorous evaluation and could emerge as best practices. If proven effective, these innovative program elements could then be disseminated and replicated to increase access for populations in need of preventive oral health care

Electron Energy Distributions at Relativistic Shock Sites: Observational Constraints from the Cygnus A Hotspots

We report new detections of the hotspots in Cygnus A at 4.5 and 8.0 microns with the Spitzer Space Telescope. Together with detailed published radio observations and synchrotron self-Compton modeling of previous X-ray detections, we reconstruct the underlying electron energy spectra of the two brightest hotspots (A and D). The low-energy portion of the electron distributions have flat power-law slopes (s~1.5) up to the break energy which corresponds almost exactly to the mass ratio between protons and electrons; we argue that these features are most likely intrinsic rather than due to absorption effects. Beyond the break, the electron spectra continue to higher energies with very steep slopes s>3. Thus, there is no evidence for the `canonical' s=2 slope expected in 1st order Fermi-type shocks within the whole observable electron energy range. We discuss the significance of these observations and the insight offered into high-energy particle acceleration processes in mildly relativistic shocks.Comment: 5 pages, 3 figures, in Extragalactic Jets: Theory and Observation from Radio to Gamma Ray, Eds. T. A. Rector and D. S. De Youn

A simplified model of the source channel of the Leksell Gamma Knife(R)^(R): testing multisource configurations with PENELOPE

A simplification of the source channel geometry of the Leksell Gamma Knife$^{\circledR}$, recently proposed by the authors and checked for a single source configuration (Al-Dweri et al 2004), has been used to calculate the dose distributions along the $x$, $y$ and $z$ axes in a water phantom with a diameter of 160~mm, for different configurations of the Gamma Knife including 201, 150 and 102 unplugged sources. The code PENELOPE (v. 2001) has been used to perform the Monte Carlo simulations. In addition, the output factors for the 14, 8 and 4~mm helmets have been calculated. The results found for the dose profiles show a qualitatively good agreement with previous ones obtained with EGS4 and PENELOPE (v. 2000) codes and with the predictions of GammaPlan$^{\circledR}$. The output factors obtained with our model agree within the statistical uncertainties with those calculated with the same Monte Carlo codes and with those measured with different techniques. Owing to the accuracy of the results obtained and to the reduction in the computational time with respect to full geometry simulations (larger than a factor 15), this simplified model opens the possibility to use Monte Carlo tools for planning purposes in the Gamma Knife$^{\circledR}$.Comment: 13 pages, 8 figures, 5 table

Innovations that Address Socioeconomic, Cultural, and Geographic Barriers to Preventive Oral Health Care

This report focuses on nine oral health innovations that integrate service delivery and workforce models in order to reduce or eliminate socioeconomic, geographic, and cultural barriers to care. Two additional reports in this series describe the remaining programs that provide care in non-dental settings and care to young children. Although the programs are diverse in their approaches as well as in the specific characteristics of the communities they serve, a common factor among them is the implementation of multiple strategies to increase the number of children from low-income families who access preventive care, and also to engage families and communities in investing in and prioritizing oral health. For low-income children and their families, the barriers that must be addressed to increase access to preventive oral health care are numerous. For example, even children covered by public insurance programs face a shortage of dentists that accept Medicaid and who specialize in pediatric dentistry.(Guay, 2004).The effects of poverty intersect with other barriers such as living in remote geographic areas and community-wide history of poor access to dental care in populations such as recent immigrants . Overcoming these barriers requires creative strategies that address transportation barriers; establish welcoming environments for oral health care; and are linguistically and culturally relevant. Each of these nine programs is based on such strategies, including:-Expanding the dental workforce through training new types of providers or adding new providers to their workforce to increase reach and community presence;-Implementing new strategies to increase the cost-effectiveness of care so that more oral health care services are available and accessible;-Providing training and technical assistance that increase opportunities for and competence in delivering oral health education and care to children;-Developing creative service delivery models that address transportation and cultural barriers as well as the fear and stigma associated with dental care that may arise in communities with historically poor access.The findings from the EAs of these programs are synthesized to highlight diverse and innovative strategies for overcoming barriers to access that have potential for rigorous evaluation that could emerge as best practices. If proven effective, these innovative program elements could then be disseminated and replicated to increase access for populations in need of preventive oral health care