Physical Sciences and Mathematics Commons^™

Gemini Mid-Ir Polarimetry Of Ngc 1068: Polarized Structures Around The Nucleus, C. Packham, S. Young, S. Fisher, K. Volk, R. Mason, J. H. Hough, P. F. Roche, Moshe Elitzur, J. Radomski, E. Perlman

Physics and Astronomy Faculty Publications

We present diffraction-limited, 10 μm imaging polarimetry data for the central regions of the archetypal Seyfert active galactic nucleus NGC 1068. The position angle of polarization is consistent with three dominant polarizing mechanisms. We identify three distinct regions of polarization: (1) north of the nucleus, arising from aligned dust in the narrow emission line region, (2) south, east, and west of the nucleus, consistent with dust being channeled toward the central engine, and (3) a central minimum of polarization consistent with a compact (≤22 pc) torus. These observations provide continuity between the geometrically and optically thick torus and the …

An Investigation Into The Effects Of Luminosity On The Mid-Infrared Spectral Energy Distributions Of Radio-Quiet Quasars, S. C. Gallagher, G. T. Richards, M. Lacy, D. C. Hines, Moshe Elitzur, L. J. Storrie-Lombardi

Physics and Astronomy Faculty Publications

We present an analysis of the effects of luminosity on the shape of the mid-infrared spectral energy distributions (SEDs) of 234 radio-quiet quasars originally presented by Richards et al. In quasars without evident dust extinction, the spectrally integrated optical and infrared luminosities are linearly correlated over nearly three decades in luminosity. We find a significant (≳99.99\% confidence) correlation between the 1.8-8.0 μm spectral index and infrared luminosity that indicates an enhancement of the mid-infrared continuum with increasing luminosity. Coupled with strong evidence for spectral curvature in more luminous quasars, we conclude that this trend is likely a manifestation of …

A Photon Dominated Region Code Comparison Study, M. Röllig, Nicholas Paul Abel, T. Bell, F. Bensch, J. Black, Gary J. Ferland, B. Jonkheid, I. Kamp, M. J. Kaufman, J. Le Bourlot, F. Le Petit, R. Meijerink, O. Morata, V. Ossenkopf, E. Roueff, Gargi Shaw, M. Spaans, A. Sternberg, J. Stutzki, W.-F. Thi, E. F. Van Dishoeck, P. A. M. Van Hoof, S. Viti, M. G. Wolfire

Physics and Astronomy Faculty Publications

Aims. We present a comparison between independent computer codes, modeling the physics and chemistry of interstellar photon dominated regions (PDRs). Our goal was to understand the mutual differences in the PDR codes and their effects on the physical and chemical structure of the model clouds, and to converge the output of different codes to a common solution.

Methods. A number of benchmark models have been created, covering low and high gas densities n = 10³,10^5.5 cm^-3 and far ultraviolet intensities χ = 10, 10⁵ in units of the Draine field (FUV: 6 < h_ν < 13.6 eV). The benchmark models were computed in two ways: one set assuming constant temperatures, thus testing the consistency of the chemical network and photo-processes, and a second set determining the temperature self consistently by solving the thermal balance, thus testing the modeling of the heating and cooling mechanisms accounting for the detailed energy balance throughout the clouds.

Results. …

Determination Of The Physical Conditions Of The Knots In The Helix Nebula From Optical And Infrared Observations, C. R. O'Dell, W. J. Henney, Gary J. Ferland

Physics and Astronomy Faculty Publications

We use new Hubble Space Telescope and archived images to clarify the nature of the ubiquitous knots in the Helix Nebula, which are variously estimated to contain a significant to majority fraction of the material ejected by its central star. We employ published far-infrared spectrophotometry and existing 2.12 μm images to establish that the population distribution of the lowest rovibrational states of H2 is close to the distribution of a gas in local thermodynamic equilibrium at 988 ± 119 K. In addition, we present calculations that show that the weakness of the H₂ 0-0 S(7) line is not …

Trans-Excision-Splicing Ribozyme And Methods Of Use, Stephen M. Testa, Michael A. Bell

Chemistry Faculty Patents

A group I intron-derived ribozyme which binds RNA in trans, excises an internal segment from within the RNA, and splices the remaining 5′ and 3′ ends of the RNA back together (the trans-excision-splicing reaction) is disclosed. The excised segment can be as long as 28 nucleotides, or more, and as little as one nucleotide. The ribozymes of the invention are easily modified to alter their sequence specificity. Such ribozymes represent a new and potentially powerful class of generally adaptable genetic therapeutics.

Dust And Pah Emission In The Star-Forming Active Nucleus Of Ngc 1097, R. E. Mason, N. A. Levenson, C. Packham, Moshe Elitzur, J. Radomski, A. O. Petric, G. S. Wright

Physics and Astronomy Faculty Publications

The nucleus of the nearby galaxy NGC 1097 is known to host a young, compact (r < 9 pc) nuclear star cluster, as well as a low-luminosity active galactic nucleus (AGN). It has been suggested both that the nuclear stellar cluster is associated with a dusty torus and that low-luminosity AGNs like NGC 1097 do not have the torus predicted by the unified model of AGNs. To investigate these contradictory possibilities we have acquired Gemini/T-ReCS 11.7 and 18.3 μm images of the central few hundred parsecs of this galaxy at <45 pc angular resolution, in which the nucleus and spectacular, kiloparsec-scale star-forming ring are detected in both bands. The small-scale mid-IR luminosity implies thermal emission from warm dust close to the central engine. Fitting of torus models shows that the observed mid-IR emission cannot be accounted for by dust heated by the central engine. Rather, the principal source heating the dust in this object is the nuclear star cluster itself, suggesting that the detected dust is not the torus of AGN unified schemes (although it is also possible that the dusty starburst itself could provide the obscuration invoked by the unified model). Comparison of Spitzer IRS and Gemini GNIRS spectra shows that, although PAH bands are strong in the immediate circumnuclear region of the galaxy, PAH emission is weak or absent in the central 19 pc. The lack of PAH emission can probably be explained largely by destruction/ionization of PAH molecules by hard photons from the nuclear star cluster. If NGC 1097 is typical, PAH emission bands may not be a useful tool with which …

Subdivision Surface-Based Geometric Modeling System, Fuhua Cheng

Computer Science Faculty Patents

A method for surface modeling of images to produce realistic images or to provide simulations with accurate surface information is provided. More particularly, the present invention relates to a new subdivision depth computation technique and to an improved label-driven adaptive subdivision technique for use in Catmull-Clark subdivision surface modeling systems. The method comprises computing a subdivision depth to determine the number of recursive subdivisions which may be performed on a control mesh to generate a plurality of finer mesh elements while preserving a predetermined error tolerance, and using the computed subdivision depth to construct an adaptively refined mesh that is …

A Magnetically Supported Photodissociation Region In M17, E. W. Pellegrini, J. A. Baldwin, C. L. Brogan, M. M. Hanson, N. P. Abel, Gary J. Ferland, H. B. Nemala, G. Shaw, Thomas H. Troland

Physics and Astronomy Faculty Publications

The southwestern (SW) part of the Galactic H II region M17 contains an obscured ionization front that is most easily seen at infrared and radio wavelengths. It is nearly edge-on, thus offering an excellent opportunity to study the way in which the gas changes from fully ionized to molecular as radiation from the ionizing stars penetrates into the gas. M17 is also one of the very few H II regions for which the magnetic field strength can be measured in the photodissociation region ( PDR) that forms the interface between the ionized and molecular gas. Here we model an observed …

Poster Session, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Identification of potential bacterial sources and levels, Red Duck Creek, Mayfield, Kentucky, Brooke Vorbeck, Travis Martin, and Mike Kemp, Dept of Industrial and Engineering Technology, Murray State University
• Water-quality trend analysis for streams in Kentucky, A.S. Crain and G.R. Martin, USGS, Louisville
• Preliminary Results of a Fecal Microbe Survey in a Eutrophic Lake, Wilgreen Lake, Madison County, Kentucky, W.S. Borowski and M.S. Albright, Depts of Earth Sciences and Geography, EKU
• Preliminary Physical and Chemical Characteristics of an Eutrophic Lake, Wilgreen Lake, Madison County, Kentucky, E.C. Jolly and W.S. Borowski, Dept of Earth Sciences, EKU
• Lethal and …

Session 2d: Superfund, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Challenges and Opportunities in Working Directly with Affected Superfund Communities in Kentucky, Lisa Gaetke, Nutrition and Food Science, UK
• Selected Chloro-Organic Detoxifications by Poly-Chelate (polyacrylic acid) and Citrate-Based Fenton Reaction at Neutral pH Environment, YongChao Li, L. G. Bachas, and Dibakar Bhattacharyya, Depts of Chemical & Materials Engineering and Chemisty, UK
• Reductive Degradation of Cholorinated Organics by Membrane-Supported Nonoparticles, Jian Xu and Dibakar Bhattacharyya, Dept of Chemical & Materials Engineering, UK

Session 2c: Education/Outreach, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• 5 Stars, 15 Students, and 5000 Trees, A.A. Gumbert and others, Extension Associate for Environmental and Natural Resource Issues, UK
• The Water Pioneers Water Quality Initiative, Stephanie Jenkins, Doug McLaren, Blake Newton, Amanda Abnee, UK
• Local and State Partnership for MS4 Success in Kentucky – Coordinated Communication, Education and Outreach, C.D. McCormick and Shelby Jett, FMSM Engineers, Louisville and Kentucky Transportation Cabinet
• Illicit Discharge Detection and Elimination: A Challenge for Kentucky’s Stormwater Program Cities, B. Tonning, R. Walker, and J. Arnold, Tetra Tech, Lexington

Session 2b: Goundwater, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Kentucky Groundwater-Quality Mapping Service, R.S. Fisher and Bart Davidson, KGS
• Kentucky Groundwater-Quality Data Search Engine, Bart Davidson and R.S. Fisher, KGS
• Water Quality in the Karst Terrane of the Sinking Creek Basin, Kentucky 2004-06, Angela S. Crain, USGS, Louisville
• Salt Movement Through the Vadose Zone of a Karst Soil – First Experiences with a Transfer Function Approach, Ole Wendroth and others, Dept Plant and Soil Sciences, UK

Session 2a: Surface Water, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Development and Application of a New Sediment Fingerprinting Methodology for the Commonwealth of Kentucky, Charles Davis and Jimmy Fox, Dept of Civil Engineering, UK
• Accounting for Construction Stormwater in TMDL Development for Sediment Impaired Streams in Rapidly Growing Residential Areas, Jon Ludwig and John Bekman, Tetra Tech, and David Montali, WVDEP
• Responses of Riparian Plant Diversity to Gradients in Flood Frequency and Severity, Patrick Lawless and Jimmy Fox, Depts of Geography and Civil Engineering, UK

Session 1d: Biology, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Long-Term Assessments and Seasonal Variations of Polychlorinated Biphenyls (PCBs) in Water, Sediments, Floodplain Soils, and Sentinel Fish Species from Big and Little Bayou Creeks, McCracken County, Kentucky, D.J. Price, Dept of Biology, UK
• Characterization of total dissolved solids (TDS) toxicity to Ceriodaphnia dubia associated with effluent discharges from a meat packaging industry, Agus Sofyan and David Price, Dept of Biology, UK
• Wilson Creek Restoration and the Response in Food Web Function and Fish Community Structure, Wesley Daniel and Jeff Jack, Dept of Biology and Center for Environmental Science, U of L

Session 1c: Epscor Projects, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Colloidal Arsenic in Poultry-Litter Amended Soils, Lisa Y. Blue and others, Dept of Chemistry, UK
• Environmental Monitoring and Assessment of Arsenic Metal in Groundwater Samples from Ballard, Carlisle, and Graves Counties, Kentucky, H.B. Fannin and others, Dept of Chemistry, Murray State University
• Environmental Monitoring and Assessment of the Groundwater Quality in Calloway County, Kentucky, Dan Kotter and others, KGS, Henderson, KY
• Land-Use Effects on Water Quality Within Lower Howard Creek Watershed, Southwestern Clark County, Kentucky, S.D. Daugherty and J.S. Dinger, Dept Earth & Environmental Sciences and KGS, UK

Session 1b: Student Research Projects, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Experimental Study of the Impact of Upland Sediment Supply upon Cohesive Streambank Erosion Part I: Fluid Turbulence, Brian Belcher and Jimmy Fox, Dept of Civil Engineering, UK
• Toward Using a Three-Dimensional Numerical Model for Simulating Hydrodynamics Near a Dam for Constructing the Rating Curve, Z.S. Shao and S.A. Yost, Dept of Civil Engineering, UK
• Property Taxation and Forest Fragmentation in Kentucky Watersheds, Scott Brodbeck and Tamara Cushing, Dept of Forestry, UK
• Solute and Particle Tracer Movement Under Various Flow Conditions in a Karst Groundwater Basin, Inner Bluegrass Region, Kentucky, J.W. Ward and others, Dept Earth and …

Session 1a: Microbial Source Tracking, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Detecting Multiple Source Origins from Fecal Bacteria Antibiotic Resistance Patterns, Sloane Ritchey and M.S. Coyne, Environmental Research Institute, EKU and Dept of Plant and Soil Sciences, UK
• Microbial Source Tracking; Limits and Application, Steve Evans, Third Rock Consultants, Lexington
• Triplett Creek Focus Study, Brian Reeder and April Haight, Institute for Regional Analysis and Public Policy, Morehead State University

Proceedings Of 2007 Kentucky Water Resources Annual Symposium, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

This conference was planned and conducted as part of the state water resources research annual program with the support and collaboration of the Department of the Interior, U.S. Geological Survey and the University of Kentucky Research Foundation, under Grant Agreement Number 06HQGR0087.

The views and conclusions contained in this document and presented at the symposium are those of the abstract authors and presenters and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government or other symposium organizers and sponsors.

He I Emission In The Orion Nebula And Implications For Primordial Helium Abundance, R. L. Porter, Gary J. Ferland, K. B. Macadam

Physics and Astronomy Faculty Publications

We apply a recently developed theoretical model of helium emission to observations of both the Orion Nebula and a sample of extragalactic H II regions. In the Orion analysis, we eliminate some weak and blended lines and compare theory and observation for our reduced line list. With our best theoretical model we find an average difference between theoretical and observed intensities (I_pred/I_obs-1)=6.5%. We argue that both the red and blue ends of the spectrum may have been inadequately corrected for reddening. For the 22 highest quality lines, with 3499 Å≤λ≤6678 Å, our best model …

Agricultural Lime Recommendations Based On Lime Quality, Greg Schwab, Lloyd W. Murdock, David C. Ditsch, Monroe Rasnake, Frank J. Sikora, Wilbur Frye

Agriculture and Natural Resources Publications

Soil acidity is one of the most important soil factors affecting crop growth and ultimately, yield and profitability. It is determined by measuring the soil pH, which is a measure of the amount of hydrogen ions in the soil solution. As soil acidity increases, the soil pH decreases. Soils tend to be naturally acidic in areas where rainfall is sufficient to cause substantial leaching of basic ions (such as calcium and magnesium), which are replaced by hydrogen ions. Most soils in Kentucky are naturally acidic because of our abundant rainfall. Some nitrogen fertilizers are also a source of soil acidity, …

How I Produced Nationally Award Winning Alfalfa Hay, Rick Alexander

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.

Roundup Ready Alfalfa: Results After One Year On The Market, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

Roundup Ready alfalfa has now been on the market for over a year with close to 30 varieties available or soon to be available across the U.S. This technology provides many new options for alfalfa producers in Kentucky. Several people have asked us which variety is highest yielding and unfortunately we have not been able to provide a good answer. The technology is so new (just approved fall 2005) that few of these varieties have been entered into University yield trials. Companies do have some private data, but they often don’t compare to the varieties you are familiar with. So …

Cowpea Aphids: Where Did They Come From, Will They Be Back?, Lee H. Townsend

Kentucky Alfalfa and Stored Forage Conference

Clearly, something was unusual back in March when large numbers of very dark aphids were found covering stems and tips in Logan, Marion, and Barren counties. They were the cowpea aphid or black legume aphid (Aphis craccivora), a sap-feeding insect known to occur in at least 28 states scattered over the US and into Canada. The cowpea aphid is the only black aphid found infesting alfalfa. Winged or wingless adults are usually shiny black, while the smaller nymphs are dull gray to black. Usually. they are lined along stems or clustered in the expanding leaf tips.

Hay Heating, Hay Sweat And Spontaneous Combustion, Tom Keene, Doug Overhults

Kentucky Alfalfa and Stored Forage Conference

Making hay in central Kentucky can be one of the most trying on farm endeavors a producer can undertake. Our plentiful moisture, rolling topography, and climate make Kentucky ideal for producing high quality forage for either grazing or hay making. However, that same moisture either in the form of rain or high humidity can sometimes make it devilishly hard to make quality hay here in Kentucky.

Alfalfa For Summer Grazing, John Johns

Kentucky Alfalfa and Stored Forage Conference

Alfalfa can make an excellent grazing forage for cattle in the summer as well as at other times of year provided that good grazing management is utilized. Alfalfa can be grazed very close to the ground but should not be grazed continuously. Initial regrowth after grazing comes from nutrient reserves in the root; therefore, a sufficient rest period or regrowth period without grazing must be allowed for these nutrients to be replenished. In summer, this rest period is 30 to 35 days. In adequate rest for root nutrient replenishment is not allowed, the plant will be weakened and stand life …

Alfalfa Hay For Horses, Robert Coleman

Kentucky Alfalfa and Stored Forage Conference

Horses are designed to eat forage and quality forage is the basis for the feeding programs of all classes of horse. However, when one considers hay as that basic forage, what criteria are used to describe quality horse hay? In general terms, quality horse hay should supply needed nutrients, be palatable and should be free of anything harmful to the horse.

Requirements For Successful Alfalfa Establishment, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Establishing a good stand of alfalfa is expensive and time consuming, but the success rate is high if you give attention to the important factors. The following steps won’t insure success, but will increase greater likelihood.

How The Alfalfa Plant Grows: Impact On Management, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the premier forage crop with high yield, high forage quality, season long productivity, drought tolerance, and extended stand life. Alfalfa requires intensive management to insure that yield, quality, and stand life are maximized. It should be planted on deep, well drained soils and maintained with optimal fertilizer inputs. It also requires adequate rest periods between cutting for hay or grazing. Alfalfa can be prone to significant insect damage and stands may require insecticide treatments. There are many details to successfully managing an alfalfa stand, but if you understand how the plant grows then you will better understand the …

Alfalfa Information On The Web, Scott Flynn

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.

Foreword And Recipients Of Kentucky Alfalfa Awards [2007], Garry D. Lacefield, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.