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Variable Effect Of Co-Infection On The Hiv Infectivity: Within-Host Dynamics And Epidemiological Significance, Diego F. Cuadros, Gisela García-Ramos Mar 2012

Variable Effect Of Co-Infection On The Hiv Infectivity: Within-Host Dynamics And Epidemiological Significance, Diego F. Cuadros, Gisela García-Ramos

Biology Faculty Publications

BACKGROUND: Recent studies have implicated viral characteristics in accounting for the variation in the HIV set-point viral load (spVL) observed among individuals. These studies have suggested that the spVL might be a heritable factor. The spVL, however, is not in an absolute equilibrium state; it is frequently perturbed by immune activations generated by co-infections, resulting in a significant amplification of the HIV viral load (VL). Here, we postulated that if the HIV replication capacity were an important determinant of the spVL, it would also determine the effect of co-infection on the VL. Then, we hypothesized that viral factors contribute to …


Drug Dosage Individualization Based On A Random-Effects Linear Model, Francisco J. Diaz, Myladis R. Cogollo, Edoardo Spina, Vincenza Santoro, Diego M. Rendon, Jose De Leon Mar 2012

Drug Dosage Individualization Based On A Random-Effects Linear Model, Francisco J. Diaz, Myladis R. Cogollo, Edoardo Spina, Vincenza Santoro, Diego M. Rendon, Jose De Leon

Psychiatry Faculty Publications

This article investigates drug dosage individualization when the patient population can be described with a random-effects linear model of a continuous pharmacokinetic or pharmacodynamic response. Specifically, we show through both decision-theoretic arguments and simulations that a published clinical algorithm may produce better individualized dosages than some traditional methods of therapeutic drug monitoring. Since empirical evidence suggests that the linear model may adequately describe drugs and patient populations, and linear models are easier to handle than the nonlinear models traditionally used in population pharmacokinetics, our results highlight the potential applicability of linear mixed models to dosage computations and personalized medicine.


Efficient Uncertainty Quantification & Sensitivity Analysis For Hypersonic Flow And Material Response Simulations Under Inherent And Model-Form Uncertainties, Serhat Hosder Mar 2012

Efficient Uncertainty Quantification & Sensitivity Analysis For Hypersonic Flow And Material Response Simulations Under Inherent And Model-Form Uncertainties, Serhat Hosder

Ablation Workshop

Accurate numerical prediction of coupled hypersonic flow fields and ablative TPS material response is challenging due to the complex nature of the physics. The uncertainties associated with various physical models used in high-enthalpy hypersonic flow and material response simulations can have significant effects on the accuracy of the results including the heat-flux and temperature distributions in various layers of ablating TPS material. These uncertainties can arise from the lack of knowledge in physical modeling (model-form or epistemic uncertainty) or inherent variations in the model inputs (aleatory or probabilistic uncertainty). It is important to include both types of uncertainty in the …


Ion-By-Ion Cooling Efficiencies, Orly Gnat, Gary J. Ferland Mar 2012

Ion-By-Ion Cooling Efficiencies, Orly Gnat, Gary J. Ferland

Physics and Astronomy Faculty Publications

We present ion-by-ion cooling efficiencies for low-density gas. We use Cloudy (version 10.00) to estimate the cooling efficiencies for each ion of the first 30 elements (H-Zn) individually. We present results for gas temperatures between 104 and 108 K, assuming low densities and optically thin conditions. When nonequilibrium ionization plays a significant role the ionization states deviate from those that obtain in collisional ionization equilibrium (CIE), and the local cooling efficiency at any given temperature depends on specific nonequilibrium ion fractions. The results presented here allow for an efficient estimate of the total cooling efficiency for any ionic …


Coupled Computation Of Fluid And Material Response For Non-Charring Ablative Materials In Hypersonic Flow, Jonathan E. Wiebenga, Iain D. Boyd Feb 2012

Coupled Computation Of Fluid And Material Response For Non-Charring Ablative Materials In Hypersonic Flow, Jonathan E. Wiebenga, Iain D. Boyd

Ablation Workshop

Hypersonic vehicles are subjected to high heat loads throughout their flight trajectories, and as a result, some form of thermal protection system (TPS) is required to ensure the vehicle’s survival. Accurate prediction of the behavior of these materials in a hypersonic environment is crucial to the efficient design of a hypersonic flight vehicle. It can be very costly and difficult, however, to experimentally replicate the flow conditions found in many hypersonic regimes, and for this reason it is desirable to be able to simulate the behavior of TPS materials under these flight conditions. This study aims to improve the modeling …


Characterization Of Material Response During Arc-Jet Testing With Optical Methods–Status And Perspectives, Michael Winter Feb 2012

Characterization Of Material Response During Arc-Jet Testing With Optical Methods–Status And Perspectives, Michael Winter

Ablation Workshop

The characterization of ablation and recession of heat shield materials during arc jet testing is an important step towards understanding the governing processes during these tests and therefore for a successful extrapolation of ground test data to flight. The behavior of ablative heat shield materials in a ground-based arc jet facility is usually monitored through measurement of temperature distributions (across the surface and in-depth), and through measurement of the final surface recession [1, 2]. These measurements are then used to calibrate/validate materials thermal response codes, which have mathematical models with reasonably good fidelity to the physics and chemistry of ablation, …


Development And Validation Of Sacram: A Swiss Approach To The Computational Response Of An Ablative Material, Ojas Joshi, Georges Duffa, Pénélope Leyland Feb 2012

Development And Validation Of Sacram: A Swiss Approach To The Computational Response Of An Ablative Material, Ojas Joshi, Georges Duffa, Pénélope Leyland

Ablation Workshop

Future space exploration missions foresee high-speed entries into planetary atmospheres. These latter imply extreme thermal conditions to which the space vehicle is exposed to, and require an appropriate thermal protection system (TPS). The interest of the scientific community in modelling and testing of materials that compose the TPS has hence greatly increased over the past few years. Since a complete set of material properties is not available in open literature, it is difficult to numerically rebuild experiments. The inter-code comparison exercise proposed by the AF/SNL/NASA Ablation Workshop aims to give a baseline platform for ablation code calibration, with a complete …


Advanced Thermal Protection Systems (Tps) And Transition Analysis: Unique Experimental Capabilities And Current Research Efforts At The University Of Texas At Arlington, Matthew Crisanti, Cody Ground, Stefano Gulli, Jared Poempipatana, Luca Maddalena Feb 2012

Advanced Thermal Protection Systems (Tps) And Transition Analysis: Unique Experimental Capabilities And Current Research Efforts At The University Of Texas At Arlington, Matthew Crisanti, Cody Ground, Stefano Gulli, Jared Poempipatana, Luca Maddalena

Ablation Workshop

A unique experimental capability in the academic panorama is the 1.6 MW-classic arc-jet facility located at the Aerodynamics Research Center of the University of Texas at Arlington. The arc-heated wind tunnel has recently been refurbished and repurposed (extended testing time of the order of minutes and testing gas-composition control) for the study and characterization of the aerothermal response of TPS candidate materials for sustained hypersonic flight.


Farmer Panel--Getting More From Your Alfalfa, Charles Powell Feb 2012

Farmer Panel--Getting More From Your Alfalfa, Charles Powell

Kentucky Alfalfa and Stored Forage Conference

Powell Farms started in 1996 with 15 acres of Alfalfa hay intended for cow/calf feed. A neighbor and his friends bought every bale that year. Over the next 14 years the only alfalfa hay our cows got to eat was when a cutting got wet and was rolled. Production per acre was good, demand exceeded production and price per bale continued to rise. Roundup Ready came on the market and we were finally able to produce clean pure high quality alfalfa. All was going well for our alfalfa business. Then came the 2008 challenge with the economic down turn, drought …


Farmer Panel--Managed Grazing And Profits, Bill Payne Feb 2012

Farmer Panel--Managed Grazing And Profits, Bill Payne

Kentucky Alfalfa and Stored Forage Conference

Profits are the goal of any business model and mine is no exception. My plan assumes that available natural resources are efficiently utilized in a responsible manner.I have chosen to implement that plan by producing, managing and marketing our forage resources by utilizing Management Intensive Grazing (MIG.)


Farmer Panel--Managing A Commercial Hay Farm, Clayton Geralds Feb 2012

Farmer Panel--Managing A Commercial Hay Farm, Clayton Geralds

Kentucky Alfalfa and Stored Forage Conference

In his presentation Clayton will discuss equipment he utilizes for establishing, maintaining, and harvesting top quality horse hay. He will also provide an overview of his expectations for yield and quality of his product as well as proper input and storage requirements.


Role And Importance Of Alfalfa In Beef Diets, Jeff Lehmkuhler Feb 2012

Role And Importance Of Alfalfa In Beef Diets, Jeff Lehmkuhler

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is often referred to as the “Queen” of forage. Is this because of its high fertility needs and more finicky soil fertility needs along with greater management for optimal growth and persistency? Or is it because of it being on top of nearly all other forages for yield and quality? Truth be told, it is likely a combination of all these factors. Alfalfa is a versatile forage as it can be harvested for hay or silage and also grazed with proper management. For these reasons, this forage can fit well in beef operations.


Alfalfa Hay For Horses, Robert Coleman Feb 2012

Alfalfa Hay For Horses, Robert Coleman

Kentucky Alfalfa and Stored Forage Conference

When horse owners consider hay for their horses, a number of criteria are generally considered. Of major importance is the hay must be free of mold and dust. It needs to contain nutrients needed by the horse and it must be palatable. If these criteria are met, the type of hay should not matter. However, that is not the case with many horse owners. When discussing the selection of hay, many owners first consider the type of hay. Can it be alfalfa or should it be a grass or how about a mix of grass and a legume. If a …


National Alfalfa & Forage Alliance, Beth Nelson Feb 2012

National Alfalfa & Forage Alliance, Beth Nelson

Kentucky Alfalfa and Stored Forage Conference

The National Alfalfa & Forage Alliance (NAFA) was formed on April 6, 2006. Its membership consists of state/regional seed associations, state/regional hay associations, genetic suppliers, seed marketers, allied industry, and research/extension affiliates. Each of these industry segments has representation on the NAFA board of directors.


Status And New Developments In Seed Coatings, Bill Talley Feb 2012

Status And New Developments In Seed Coatings, Bill Talley

Kentucky Alfalfa and Stored Forage Conference

The acceptance and use of coated alfalfa seed has become the standard of how alfalfa seed is being sold. Coated seed, refers to a buildup in coating material of 10-34%. Seventy percent of proprietary alfalfa seed is now buildup coated, and 80 % of that amount is a 34% coating. The remaining is a 10% buildup and is usually only used as a carrier for inoculation and fungicide. The higher buildup coatings are able to carry more active ingredients that also enhance the agronomic benefit to the young seedling. The benefits to the young seedling, from the components of the …


Kentucky Department Of Agriculture Hay Testing Program, Kim Field Feb 2012

Kentucky Department Of Agriculture Hay Testing Program, Kim Field

Kentucky Alfalfa and Stored Forage Conference

The Kentucky Department of Agriculture offers a forage testing service which provides nutritional and energy value information. A Kentucky Department of Agriculture staff member will take sample(s) of hay and/or haylage at the farm and analyze them in the Kentucky Department of Agriculture Forage Laboratory located in Frankfort. Tested forages can mean higher profit, whether feeding cattle, horses, goats, sheep or other livestock. By knowing the nutritional and energy value, you can minimize your cost and maximize your production.


Marketing Quality Hay, Tom Keene Feb 2012

Marketing Quality Hay, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

When marketing quality alfalfa hay, you basically have two markets that you are going to try to target. First, you are going to be in the cash hay market, that’s where you will sell alfalfa hay to several different entities…..locally, statewide, nationally, or potentially internationally. Secondly, and more commonly, you will be marketing your hay to your own livestock enterprise on your farm. Several times every month, I have people call me and ask me what their hay is worth. I tell them very honestly I have no idea what their hay is worth; only by keeping track of their …


How Are Roundup Ready Varieties Performing, S. Ray Smith Feb 2012

How Are Roundup Ready Varieties Performing, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

Roundup Ready® Alfalfa

The most significant new development in alfalfa varieties was the January 27, 2011 decision by USDA to deregulate Roundup Ready® Alfalfa (RRA) without conditions. This was the final step in an extensive environmental review process by the USDA that took place over a 4 year period of time. If you would like to know more about the safety of Roundup Ready® Alfalfa you can review the complete Environmental Impact Statement at: http://www.aphis.usda.gov/biotechnology/downloads/alfalfa/gt_alfalfa%20_feis.pdf.

Most importantly, seed dealers in Kentucky and surrounding states now have Roundup varieties available for sale.


Getting More From Your Alfalfa, Garry D. Lacefield Feb 2012

Getting More From Your Alfalfa, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Today marks the 32nd consecutive year we have come together to discuss alfalfa and its role on your farm, in Kentucky, and our nation. Over these 32 years we have discussed many topics and seen many advances, unfortunately we aren’t making progress relative to acres, yield and quality that I would like to see. Maybe I am getting impatient as I am actually thinking about retirement. Now wait, you are one step ahead of me. I know you are thinking he has shown many graphs, tables and charts over the years showing how we have improved and yes, I know …


Foreword And Recipients Of Kentucky Alfalfa Awards [2012], Garry D. Lacefield, Christi L. Forsythe Feb 2012

Foreword And Recipients Of Kentucky Alfalfa Awards [2012], Garry D. Lacefield, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


On The Unification Of Active Galactic Nuclei, Moshe Elitzur Feb 2012

On The Unification Of Active Galactic Nuclei, Moshe Elitzur

Physics and Astronomy Faculty Publications

The inevitable spread in properties of the toroidal obscuration of active galactic nuclei (AGNs) invalidates the widespread notion that type 1 and 2 AGNs are intrinsically the same objects, drawn randomly from the distribution of torus covering factors. Instead, AGNs are drawn preferentially from the distribution; type 2 are more likely drawn from the distribution higher end, type 1 from its lower end. Type 2 AGNs have a higher IR luminosity, lower narrow-line luminosity, and a higher fraction of Compton thick X-ray obscuration than type 1. Meaningful studies of unification statistics cannot be conducted without first determining the intrinsic distribution …


Division Of Undergraduate Education Proposal To The University Of Kentucky Faculty Senate Council: Establishing Policy And Guidelines For University Of Kentucky Dual Credit Partnerships With Secondary Schools, Randolph Hollingsworth Feb 2012

Division Of Undergraduate Education Proposal To The University Of Kentucky Faculty Senate Council: Establishing Policy And Guidelines For University Of Kentucky Dual Credit Partnerships With Secondary Schools, Randolph Hollingsworth

Undergraduate Education White Papers

This proposal was presented via handouts and accompanying slides to the University of Kentucky Faculty Senate Council on February 20, 2012. The proposal hinges on two main purposes:

  1. an alternative for Kentucky's high school students that choose to accelerate their time to degree by completing a challenging course at UK; and,
  2. a strategic improvement to existing enrollments at UK by high school students that would lead to more long-term relationships and shorten time to a college degree from UK.

The proposal includes definitions of terms commonly used, a few examples from UK benchmark institutions and an example lifecycle for the …


Ablation Test-Case Series #2. Numerical Simulation Of Ablative-Material Response: Code And Model Comparisons, Jean R. Lachaud, Alexandre Martin, Tom Van Eekelen, Ioana Cozmuta Feb 2012

Ablation Test-Case Series #2. Numerical Simulation Of Ablative-Material Response: Code And Model Comparisons, Jean R. Lachaud, Alexandre Martin, Tom Van Eekelen, Ioana Cozmuta

Mechanical Engineering Faculty Publications

This test-case series on the numerical simulation of the response of ablative-materials really started out of pure curiosity. Code developers and users were curious to see "how the codes compare" and "what is the effect of the different hypotheses in the models implemented". The objective of these test-case series is to propose problems of increasing complexity until it is agreed that the most-elaborated well-defined problem is formulated. The first test-case was mostly a simple heat transfer problem chosen for it’s simplicity (it is summarized in section 2.1). The second test-case series goes one step further, with the objective of reaching …


Ablation Test-Case Series #3. Numerical Simulation Of Ablative-Material Response: Code And Model Comparisons, Tom Van Eekelen, Jean R. Lachaud, Alexandre Martin, Ioana Cozmuta Feb 2012

Ablation Test-Case Series #3. Numerical Simulation Of Ablative-Material Response: Code And Model Comparisons, Tom Van Eekelen, Jean R. Lachaud, Alexandre Martin, Ioana Cozmuta

Mechanical Engineering Faculty Publications

The test-case series #3 will be a further extension of the tests defined within the framework of the NASA ablation modelling workshops. In order to reduce the amount of work, all tests within test-case series #3, will use the TACOT material defined by Lachaud et al. The main goal of this new series, is to test the 3D modelling capabilities of the participating codes. The first 1D results were presented at the 4th Ablation workshop, and together with the results of the second test-case series, will be discussed and analyzed more thoroughly at the 5th Ablation Workshop, Feb. 28- March …


2012-2013 Lime And Nutrient Recommendations, Lloyd Murdock, Edwin Ritchey Feb 2012

2012-2013 Lime And Nutrient Recommendations, Lloyd Murdock, Edwin Ritchey

Agriculture and Natural Resources Publications

The recommendations found in this publication are a result of a biennial review of soil fertility research and soil test data collected in Kentucky.


Agricultural Production Economics, David L. Debertin Feb 2012

Agricultural Production Economics, David L. Debertin

Agricultural Economics Textbook Gallery

Agricultural Production Economics (Second Edition, Amazon Createspace 2012) is a revised edition of the textbook Agricultural Production Economics published by Macmillan in 1986 (ISBN 0-02-328060-3). This is a free pdf download of the entire book. As the author, I own the copyright. Amazon markets bound print copies of the book at amazon.com at a nominal price for classroom use. The book can also be ordered through college bookstores using the following ISBN numbers:

  • ISBN-13 978-1469960647
  • ISBN-10 1469960648

The format and coverage remains similar to the first edition, many small revisions and updates have been made. All graphs have been redrawn …


Star Formation In Self-Gravitating Disks In Active Galactic Nuclei. Ii. Episodic Formation Of Broad-Line Regions, Jian-Min Wang, Pu Du, Jack A. Baldwin, Jun-Qiang Ge, Chen Hu, Gary J. Ferland Feb 2012

Star Formation In Self-Gravitating Disks In Active Galactic Nuclei. Ii. Episodic Formation Of Broad-Line Regions, Jian-Min Wang, Pu Du, Jack A. Baldwin, Jun-Qiang Ge, Chen Hu, Gary J. Ferland

Physics and Astronomy Faculty Publications

This is the second in a series of papers discussing the process and effects of star formation in the self-gravitating disk around the supermassive black holes in active galactic nuclei (AGNs). We have previously suggested that warm skins are formed above the star-forming (SF) disk through the diffusion of warm gas driven by supernova explosions. Here we study the evolution of the warm skins when they are exposed to the powerful radiation from the inner part of the accretion disk. The skins initially are heated to the Compton temperature, forming a Compton atmosphere (CAS) whose subsequent evolution is divided into …


Rovibrationally Resolved Direct Photodissociation Through The Lyman And Werner Transitions Of H2 For Fuv/X-Ray-Irradiated Environments, C. D. Gay, N. P. Abel, R. L. Porter, P. C. Stancil, Gary J. Ferland, G. Shaw, P. A. M. Vanhoof, R. J. R. Williams Jan 2012

Rovibrationally Resolved Direct Photodissociation Through The Lyman And Werner Transitions Of H2 For Fuv/X-Ray-Irradiated Environments, C. D. Gay, N. P. Abel, R. L. Porter, P. C. Stancil, Gary J. Ferland, G. Shaw, P. A. M. Vanhoof, R. J. R. Williams

Physics and Astronomy Faculty Publications

Using ab initio potential curves and dipole transition moments, cross-section calculations were performed for the direct continuum photodissociation of H2 through the B1Σ+u ← X1Σ+g (Lyman) and C1Πu ← X1Σ+g (Werner) transitions. Partial cross-sections were obtained for wavelengths from 100 Å to the dissociation threshold between the upper electronic state and each of the 301 bound rovibrational levels v''J'' within the ground electronic state. The resulting cross-sections are incorporated into three representative classes of interstellar gas models: diffuse clouds, photon-dominated regions, and …


Effect Of Tray Type And Tray Covering On Wicking Speed, Germination, And Spiral Rooting Of Tobacco, William A. Bailey, Bill Pitt Jan 2012

Effect Of Tray Type And Tray Covering On Wicking Speed, Germination, And Spiral Rooting Of Tobacco, William A. Bailey, Bill Pitt

Plant and Soil Sciences Research Report

Poor tray wicking and spiral rooting continue to be recurring concerns in tobacco float systems. Poor wicking of trays can usually be attributed to old media or media that was improperly stored for extended periods of time. Tray design may also influence speed of wicking. The clay-based pelleting materials used to coat tobacco seeds are thought to cause damage to the emerging root radical under certain conditions, leading to an increased incidence of spiral root. Practices that change the microenvironment at the top of the cell area surrounding the seed may reduce spiral rooting by altering the breakdown of the …


High Performance Modeling Of Atmospheric Re-Entry Vehicles, Alexandre Martin, Leonardo C. Scalabrin, Iain D. Boyd Jan 2012

High Performance Modeling Of Atmospheric Re-Entry Vehicles, Alexandre Martin, Leonardo C. Scalabrin, Iain D. Boyd

Mechanical Engineering Faculty Publications

Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, an appropriate gas flow chemistry model needs …