395 research outputs found

    Mass Chlamydia Screening vs. Opportunistic Screening in College Freshmen

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    Chlamydia trachomatis is the number one sexually transmitted disease in the United States and North Dakota. It has seen a steady rise in the past 10 years. Chlamydia is a preventable and treatable disease but the current lack of sufficient screening and identification of this disease often leads to many health consequences. Standard USPSTF screening guidelines are available for practitioners but despite the use of recommended opportunistic screening with patients, only about 3 8% of females ages 15-25 years are being screened appropriately and there is even less identification in males. There is growing literature on the efficacy of using mass chlamydia screening; especially in high school and college populations due to the high risk status found in these age groups. Mass chlamydia screenings are feasible, reproducible, acceptable among students and staff, and are cost-effective. Several studies have implemented mass screenings to determine effectiveness but further investigation into additional benefits and limitations of mass chlamydia screening needs to be explored. Researchers are also examining the impact of combining appropriate education with screening, and the use of patient self-selection, to yield increased screening rates without causing over-screening and to yield more cost-effective screening methods. College maybe an ideal avenue to mass screen a large number of young adults simultaneously and ultimately decrease the growing incidence of Chlamydia in our countr

    An Initial Exploration of Improved Numerics within the Guidelines of the Negative Spalart-Allmaras Turbulence Model

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    A simple modification to the negative Spalart-Allmaras turbulence model is suggested so that when the turbulence working variable, ~v, is negative, diagonal dominance is increased, as is the tendency for the time-advancement scheme to push e toward positive values. Owing to the fact that the modification is only active when ~v is less than zero, the physical model is left unchanged. Using the proposed modification with a strong implicit solver based on Newton's method, convergence rates can be somewhat improved, with typical reductions in iterations and computer time on the order of 15-50%. The benefits are realized primarily when second- or higher-order accuracy is used for discretizing the convective terms in the turbulence model because of large overshoots that can occur with these schemes at the edges of boundary layers and wakes. For flowfields with few regions of negative ~v, or on very fine meshes where ~v is always greater than zero, little or no benefits should be expected

    On Blockage Corrections for Two-dimensional Wind Tunnel Tests Using the Wall-pressure Signature Method

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    The Wall-Pressure Signature Method for correcting low-speed wind tunnel data to free-air conditions has been revised and improved for two-dimensional tests of bluff bodies. The method uses experimentally measured tunnel wall pressures to approximately reconstruct the flow field about the body with potential sources and sinks. With the use of these sources and sinks, the measured drag and tunnel dynamic pressure are corrected for blockage effects. Good agreement is obtained with simpler methods for cases in which the blockage corrections were about 10% of the nominal drag values

    Phänotypen, Mutationsdetektionsrate und Mutationsspektrum in einem Kollektiv von Patienten mit kongenitalen myasthenen Syndromen (CMS)

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    Turbulence Model Implementation and Verification in the SENSEI CFD Code

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    This paper outlines the implementation and verification of the negative Spalart-Allmaras turbulence model into the SENSEI CFD code. The SA-neg turbulence model is implemented in a flexible, object-oriented framework where additional turbulence models can be easily added. In addition to outlining the new turbulence modeling framework in SENSEI, an overview of the other general improvements to SENSEI is provided. The results for four 2D test cases are compared to results from CFL3D and FUN3D to verify that the turbulence models are implemented properly. Several differences in the results from SENSEI, CFL3D, and FUN3D are identified and are attributed to differences in the implementation and discretization order of the boundary conditions as well as the order of discretization of the turbulence model. When a solid surface is located near or intersects an inflow or outflow boundary, higher order boundary conditions should be used to limit their effect on the forces on the surface. When the turbulence equations are discretized using second order spatial accuracy, the edge of the eddy viscosity profile seems to be sharper than when a first order discretization is used. However, the discretization order of the turbulence equation does not have a significant impact on output quantities of interest, such as pressure and viscous drag, for the cases studied

    Demonstration of a Thermally Coupled Row-Column SNSPD Imaging Array

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    While single-pixel superconducting nanowire single photon detectors (SNSPDs) have demonstrated remarkable efficiency and timing performance from the UV to near-IR, scaling these devices to large imaging arrays remains challenging. Here, we propose a new SNSPD multiplexing system using thermal coupling and detection correlations between two photosensitive layers of an array. Using this architecture with the channels of one layer oriented in rows and the second layer in columns, we demonstrate imaging capability in 16-pixel arrays with accurate spot tracking at the few-photon level. We also explore the performance trade-offs of orienting the top layer nanowires parallel and perpendicular to the bottom layer. The thermally coupled row-column scheme is readily able to scale to the kilopixel size with existing readout systems and, when combined with other multiplexing architectures, has the potential to enable megapixel scale SNSPD imaging arrays
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