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Full-Text Articles in Physical Sciences and Mathematics

Assessment Of Water Quality Trends In The North Fork Of Kentucky River Basin: Focus On Pathogen Impairment, Kentucky Water Resources Research Institute Jan 2008

Assessment Of Water Quality Trends In The North Fork Of Kentucky River Basin: Focus On Pathogen Impairment, Kentucky Water Resources Research Institute

KWRRI Research Reports

This project consisted of analyzing existing water quality data for streams in the Upper Forks of Kentucky River Basin, with a particular focus on pathogen trends. According to the most recent 303(d) list of Kentucky waters, the majority of streams assessed in the Upper Forks of Kentucky River Basin are impaired for primary recreational contact as a result of pathogens. The state pathogen standard for primary contact recreation is expressed in a dual form which specifies that the 30-day geometric mean of fecal coliform counts not exceed 200 colonies per 100 mL (on a minimum of five samples) and not …


Kentucky Water Resources Research Institute Annual Technical Report Fy 2007, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2008

Kentucky Water Resources Research Institute Annual Technical Report Fy 2007, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2007 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each student research enhancement project conducted during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable awards and achievements during the year.


Algebraic And Combinatorial Properties Of Certain Toric Ideals In Theory And Applications, Sonja Petrovic Jan 2008

Algebraic And Combinatorial Properties Of Certain Toric Ideals In Theory And Applications, Sonja Petrovic

University of Kentucky Doctoral Dissertations

This work focuses on commutative algebra, its combinatorial and computational aspects, and its interactions with statistics. The main objects of interest are projective varieties in Pn, algebraic properties of their coordinate rings, and the combinatorial invariants, such as Hilbert series and Gröbner fans, of their defining ideals. Specifically, the ideals in this work are all toric ideals, and they come in three flavors: they are defining ideals of a family of classical varieties called rational normal scrolls, cut ideals that can be associated to a graph, and phylogenetic ideals arising in a new and increasingly popular area of …


Mechanistic Investigations Of The Trans Excision-Splicing And Trans Insertion-Splicing Reaction, Perry Patrick Dotson Ii Jan 2008

Mechanistic Investigations Of The Trans Excision-Splicing And Trans Insertion-Splicing Reaction, Perry Patrick Dotson Ii

University of Kentucky Doctoral Dissertations

Group I intron-derived ribozymes are catalytic RNAs that have been engineered to catalyze a variety of different reactions, in addition to the native self-splicing reaction. One such ribozyme, derived from a group I intron of Pneumocystis carinii, can modify RNA transcripts through either the excision or insertion of RNA sequences. These reactions are mediated through the trans excision-splicing (TES) or trans insertionsplicing (TIS) reaction pathways. To increase our current understanding of these reactions, as well as their general applicability, a mechanistic and kinetic framework for the TES reaction was established. Furthermore, additional ribozymes were investigated for their ability to …


Precision Measurements Of The Neutron Electric Form Factor At High Momentum Transfers, Ameya Suresh Kolarkar Jan 2008

Precision Measurements Of The Neutron Electric Form Factor At High Momentum Transfers, Ameya Suresh Kolarkar

University of Kentucky Doctoral Dissertations

The neutron, although electrically neutral, is composed of elementary charged particles and as a result, possesses a charge distribution within. The charge distribution can be studied by measuring a quantity called the neutron electric form factor, GnE. Experiment E02-013 at Jefferson Lab’s Hall A measured GnE at high four-momentum transfer values of Q2 = 1.2, 1.7, 2.5 and 3.4 (GeV/c)2 in double polarized semi-exclusive 3He(e, e'n) scattering in quasi-elestic kinematics by measuring the transverse asymmetry AT of the cross section.

The neutron electric form factor is essential to …


The H-Vectors Of Matroids And The Arithmetic Degree Of Squarefree Strongly Stable Ideals, Erik Stokes Jan 2008

The H-Vectors Of Matroids And The Arithmetic Degree Of Squarefree Strongly Stable Ideals, Erik Stokes

University of Kentucky Doctoral Dissertations

Making use of algebraic and combinatorial techniques, we study two topics: the arithmetic degree of squarefree strongly stable ideals and the h-vectors of matroid complexes.

For a squarefree monomial ideal, I, the arithmetic degree of I is the number of facets of the simplicial complex which has I as its Stanley-Reisner ideal. We consider the case when I is squarefree strongly stable, in which case we give an exact formula for the arithmetic degree in terms of the minimal generators of I as well as a lower bound resembling that from the Multiplicity Conjecture. Using this, we can …


Benzene-1,3-Diamidoethanethiol (Bdeth2) And Its Metal Compounds, Kamruz Md Zaman Jan 2008

Benzene-1,3-Diamidoethanethiol (Bdeth2) And Its Metal Compounds, Kamruz Md Zaman

University of Kentucky Doctoral Dissertations

There is a global need to find a permanent and readily implemented solution to the problem of heavy metal pollution in aqueous environments. A dithiol compound, benzene-1,3-diamidoethanethiol (BDETH2), also known as N,N'-bis(2-mercaptoethyl) isophthalamide or N,N'-bis(2-mercaptoethyl)-1,3-benzenedicarboxamide, capable of binding divalent metal ions, has been synthesized and characterized. A broad range of BDET-metal compounds, spanning the periodic chart, has been prepared and characterized by IR, MS, EA, Raman, XAFS and TGA. The characteristics of the BDET-M compounds were determined through secondary reactions. In an effort to derivatize BDET-M compounds through alkylalumination a new cyclic compound, 1,3- bis(4,5-dihydrothiazolo)benzene, has …


Regulation Of L-Type Voltage-Dependnet Calcium Channels By The Rem Gtpase, Chunyan Pang Jan 2008

Regulation Of L-Type Voltage-Dependnet Calcium Channels By The Rem Gtpase, Chunyan Pang

University of Kentucky Doctoral Dissertations

The Rem, Rem2, Rad, and Gem/Kir GTPases, comprise a novel subfamily of the small Ras-related GTP-binding proteins known as the RGK GTPases, and have been shown to function as potent negative regulators of high voltage-activated (HVA) Ca2+ channels upon overexpression. HVA Ca2+ channels modulate Ca2+ influx in response to membrane depolarization to regulate a wide variety of cellular functions and they minimally consist of a pore-forming α1 subunit, an intracellular β subunit, and a transmembrane complex α2/δ subunit. While the mechanisms underlying RGK-mediated Ca2+ channel regulation remain poorly defined, it appears that both membrane …


A Systematic Study Of Thermodynamic And Transport Properties Of Layered CaN+1(Ru1-XCrX)NO3n+1, Vinobalan Durairaj Jan 2008

A Systematic Study Of Thermodynamic And Transport Properties Of Layered CaN+1(Ru1-XCrX)NO3n+1, Vinobalan Durairaj

University of Kentucky Doctoral Dissertations

Orbital degrees of freedom play vital role in prompting novel phenomena in ruthenium based Ruddlesden-Popper compounds through coupling of orbits to spin and lattice. Physical properties are then particularly susceptible to small perturbations by external magnetic fields and/or slight structural changes. Current study pertains to the impact when a more-extended 4d Ruthenium ion is replaced by a less-extended 3d Chromium ion.

Perovskite CaRuO3 (n=∞) is characterized by borderline magnetism and non- Fermi liquid behavior – common occurrences in quantum critical compounds. Remarkably, Cr substitution as low as x=0.05 abruptly drives CaRu1−xCrxO3 from a paramagnetic …


Empirical Processes And Roc Curves With An Application To Linear Combinations Of Diagnostic Tests, Costel Chirila Jan 2008

Empirical Processes And Roc Curves With An Application To Linear Combinations Of Diagnostic Tests, Costel Chirila

University of Kentucky Doctoral Dissertations

The Receiver Operating Characteristic (ROC) curve is the plot of Sensitivity vs. 1- Specificity of a quantitative diagnostic test, for a wide range of cut-off points c. The empirical ROC curve is probably the most used nonparametric estimator of the ROC curve. The asymptotic properties of this estimator were first developed by Hsieh and Turnbull (1996) based on strong approximations for quantile processes. Jensen et al. (2000) provided a general method to obtain regional confidence bands for the empirical ROC curve, based on its asymptotic distribution.

Since most biomarkers do not have high enough sensitivity and specificity to …


Carbon Nanotube Supported Metal Catalysts For NoX Reduction Using Hydrocarbon Reductants, Eduardo Santillan-Jimenez Jan 2008

Carbon Nanotube Supported Metal Catalysts For NoX Reduction Using Hydrocarbon Reductants, Eduardo Santillan-Jimenez

University of Kentucky Doctoral Dissertations

Nitrogen oxides (NOx) are atmospheric pollutants that pose a serious threat to both the environment and human health. Although catalytic deNOx technologies for engines working under stoichiometric air-to-fuel ratios (i.e., most gasoline engines) are already available, their performance is unsatisfactory under excess air conditions like those under which diesel engines operate.

The selective catalytic reduction of NOx with hydrocarbon reductants (HC-SCR) is a potential deNOxsolution for diesel engines, whose operating temperatures are 150-500 ºC. Given that is unlikely for a single catalyst to show acceptable activity throughout this entire temperature span, the use of …


Paleogene Mirelands Of The Upper Mississippi Embayment, Western Kentucky, Jennifer Marie Klein O'Keefe Jan 2008

Paleogene Mirelands Of The Upper Mississippi Embayment, Western Kentucky, Jennifer Marie Klein O'Keefe

University of Kentucky Doctoral Dissertations

Detailed petrography, geochemistry, and palynology together describe the depositional environments and paleoecology of an abandoned meander-fill system in western Kentucky. Oriented block petrography reveals alternating clay-rich and attrinite-rich zones of variable thickness. Woody tissues, where present, do not show dessication features and deflation layers could not be identified. Overall, petrography is indicative of a topogenous mire. Mire palyno-assemblages are less diverse than assemblages reported from clays in the region. Castanea-Cupuliferoidaepollenites assemblages dominate the entire system and other tree pollen are common; fungal spores are relatively uncommon. Weighted statistical analyses reveal ecological groupings beyond this dominance and define botanical succession within …


The Mobility Of Fecal Indicator Microorganisms Within A Karst Groundwater Basin In The Inner Bluegrass Region, Kentucky, James Wade Ward Jan 2008

The Mobility Of Fecal Indicator Microorganisms Within A Karst Groundwater Basin In The Inner Bluegrass Region, Kentucky, James Wade Ward

University of Kentucky Doctoral Dissertations

This project implemented novel approaches to assess the source, age, concentration and mobility of fecal indicator microorganisms within a karst groundwater system. Research was conducted in the well-characterized Blue Hole Spring karst groundwater basin in Versailles, Woodford County, Kentucky. At this site the AC/TC ratio and fecal coliform (FC) bacteria counts were used to delineate sources of fecal inputs and determine relative age of the fecal matter. An aging experiment using indicator bacteria (total coliform (TC) and atypical colonies (AC)), which approximated subsurface conditions, indicated that changes in the AC/TC ratio are likely to be retarded during bacterial transport through …


Summary Of Kentucky River Watershed Watch 2008 Water Samplig Results, Kentucky Water Resources Research Institute, Kentucky River Authority Jan 2008

Summary Of Kentucky River Watershed Watch 2008 Water Samplig Results, Kentucky Water Resources Research Institute, Kentucky River Authority

Kentucky River Watershed Watch

No abstract provided.


Merged Ionization/Dissociation Fronts In Planetary Nebulae, William J. Henney, R. J. R. Williams, Gary J. Ferland, Gargi Shaw, C. R. O'Dell Dec 2007

Merged Ionization/Dissociation Fronts In Planetary Nebulae, William J. Henney, R. J. R. Williams, Gary J. Ferland, Gargi Shaw, C. R. O'Dell

Physics and Astronomy Faculty Publications

The hydrogen ionization and dissociation front around an ultraviolet radiation source should merge when the ratio of ionizing photon flux to gas density is sufficiently low and the spectrum is sufficiently hard. This regime is particularly relevant to the molecular knots that are commonly found in evolved planetary nebulae, such as the Helix Nebula, where traditional models of photodissociation regions have proved unable to explain the high observed luminosity in H2 lines. In this paper we present results for the structure and steady state dynamics of such advection-dominated merged fronts, calculated using the Cloudy plasma/molecular physics code. We find …


Spitzer Irs Observations Of Seyfert 1.8 And 1.9 Galaxies: A Comparison With Seyfert 1 And Seyfert 2, R. P. Deo, D. M. Crenshaw, S. B. Kraemer, M. Dietrich, Moshe Elitzur, H. Teplitz, T. J. Turner Dec 2007

Spitzer Irs Observations Of Seyfert 1.8 And 1.9 Galaxies: A Comparison With Seyfert 1 And Seyfert 2, R. P. Deo, D. M. Crenshaw, S. B. Kraemer, M. Dietrich, Moshe Elitzur, H. Teplitz, T. J. Turner

Physics and Astronomy Faculty Publications

We present Spitzer mid-infrared spectra of 12 Seyfert 1.8 and 1.9 galaxies over the 5-38 μm region. We compare the spectral characteristics of this sample to those of 58 Seyfert 1 and 2 galaxies from the Spitzer archives. An analysis of the spectral shapes, the silicate 10 μm feature and the emission-line fluxes have enabled us to characterize the mid-IR properties of Seyfert 1.8/1.9s. We find that the EWs of the 10 μm silicate feature are generally weak in all Seyfert galaxies, as previously reported by several studies. The few Seyfert galaxies in this sample that show …


Forage Spokesman Information, Lowell J. Clifford, Barry Drury, John Mcglone, Mac Stone Oct 2007

Forage Spokesman Information, Lowell J. Clifford, Barry Drury, John Mcglone, Mac Stone

Kentucky Grazing Conference

No abstract provided.


Techniques For Reducing Mud Problems And Improving Pasture Abused Areas, Ken Johnson Oct 2007

Techniques For Reducing Mud Problems And Improving Pasture Abused Areas, Ken Johnson

Kentucky Grazing Conference

I would like to approach this topic from two directions, mud control and then problem areas. Mud control in concentrated areas almost impossible with forages alone. Using a mud control product is usually advised. I will talk about several.


My Experiences With Summer Lovegrass, Tim Phillips Oct 2007

My Experiences With Summer Lovegrass, Tim Phillips

Kentucky Grazing Conference

I first heard about teff (Eragrostis tef) being used as a hay crop in early 2006 at a meeting near the Shenandoah Valley area of Virginia. The meeting was about orchardgrass production, so I was speaking about new varieties that are available for producers to grow. Several farmers had experienced massive stand losses of their established orchardgrass hay fields, so they had tried this ‘new’ summer annual grass. Some of the farmers were surprised that I knew about this grass, but I didn’t know about its use as a hay or pasture grass. Teff is the Ethiopian name for a …


Experiences With "Teff" (Summer Love Grass) In Kentucky, Bob Jaynes Oct 2007

Experiences With "Teff" (Summer Love Grass) In Kentucky, Bob Jaynes

Kentucky Grazing Conference

Following publicity about the Klamath Experiment Station evaluation of Teff as an annual forage in 2003 and 2004, requests for more information and seed sources kept KES staff busy for weeks last spring. We received over 300 contacts from 41 states. Local seed salesman Laverne Hankins processed over 150 orders for more than 5 tons of seed. Those who received seed were sent a questionnaire this fall in hopes that we would get feedback on growers experience with this new forage species. To date we have received responses from about 15 growers.


Options For Summer Grazing, David C. Ditsch Oct 2007

Options For Summer Grazing, David C. Ditsch

Kentucky Grazing Conference

Summer is the time during the growing season when shortages of forage most often occur in Kentucky. The summer of 2007 will long be remembered as one the warmest and driest in recent years and cause many livestock producers to evaluate their current forage systems. Most Kentucky pastures are predominately cool-season grasses such as tall fescue, orchardgrass and bluegrass. During the historically hot, dry periods in July and August, these species produce very little growth and can quickly become overgrazed. At this point, some producers have no alternative except to buy feed or begin feeding stored forage intended for winter …


Does Grazing Method Matter?, Garry D. Lacefield Oct 2007

Does Grazing Method Matter?, Garry D. Lacefield

Kentucky Grazing Conference

Interest in and opportunities for grazing continues to increase not only in Kentucky, but throughout the U.S. In Wisconsin, 12% or approximately 5000 dairymen are now using grazing. In Michigan, over 40% of the dairymen are using grazing for a significant part of their feed requirements. Over 15% of these dairymen are using intensive grazing. Similar numbers exist for Pennsylvania.


Surviving The 2007 Drought, Roy Burris Oct 2007

Surviving The 2007 Drought, Roy Burris

Kentucky Grazing Conference

Kentucky beef producers could feel the effects of the ’07 drought for a long time. Decisions made now will impact the ’08 and ’09 calf crops. The current hay/feed shortage has stimulated a lot of “panic buying”. Feedstuffs with very low nutritive values are being purchased at an alarming rate. These “feeds” are being purchased at much higher costs than we normally pay for good quality hay. If properly supplemented, they can be used successfully. However, their use to replace the normal hay supply could have disastrous results.


Recovering From The "Freeze" And "Drought" Of 2007, S. Ray Smith Oct 2007

Recovering From The "Freeze" And "Drought" Of 2007, S. Ray Smith

Kentucky Grazing Conference

As all of you know, 2007 has been a devastating year for forage agriculture in Kentucky. The season started with an abnormally warm 7 weeks during late winter and early spring, which promoted lush vegetative growth. Normally this would have been a “good thing”, but it actually made forage plants more vulnerable to below freezing temperatures. Then the severe freeze occurred, with April 7, 8, and 9 the coldest 3 day period in April in KY history. Pastures were stunted for weeks and first cut hay yields were reduced by 35 to 100%. At this point we were still hopeful …


Foreword And Kfgc Award Winners [2007], Garry D. Lacefield, Christi L. Forsythe Oct 2007

Foreword And Kfgc Award Winners [2007], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


A Simple Array Platform For Microrna Analysis And Its Application In Mouse Tissues, Xiaoqing Tang, Jozsef Gal, Xun Zhuang, Wang-Xia Wang, Haining Zhu, Guiliang Tang Oct 2007

A Simple Array Platform For Microrna Analysis And Its Application In Mouse Tissues, Xiaoqing Tang, Jozsef Gal, Xun Zhuang, Wang-Xia Wang, Haining Zhu, Guiliang Tang

Plant and Soil Sciences Faculty Publications

MicroRNAs (miRNAs) are a novel class of small noncoding RNAs that regulate gene expression at the post-transcriptional level and play a critical role in many important biological processes. Most miRNAs are conserved between humans and mice, which makes it possible to analyze their expressions with a set of selected array probes. Here, we report a simple array platform that can detect 553 nonredundant miRNAs encompassing the entire set of miRNAs for humans and mice. The platform features carefully selected and designed probes with optimized hybridization parameters. Potential cross-reaction between mature miRNAs and their precursors was investigated. The array platform was …


The Agn-Obscuring Torus: The End Of The "Doughnut" Paradigm?, Moshe Elitzur, Isaac Shlosman Sep 2007

The Agn-Obscuring Torus: The End Of The "Doughnut" Paradigm?, Moshe Elitzur, Isaac Shlosman

Physics and Astronomy Faculty Publications

Unified schemes of active galactic nuclei (AGNs) require an obscuring dusty torus around the central engine. The compact sizes (only a few parsecs) determined in recent high-resolution observations require that the obscuring matter be clumpy and located inside the region where the black hole gravity dominates over the galactic bulge. This location is in line with the scenario depicting the torus as the region of the clumpy wind coming off the accretion disk in which the clouds are dusty and optically thick. We study here the outflow scenario within the framework of hydromagnetic disk winds, incorporating the cloud properties determined …


Revisiting He-Like X-Ray Emission-Line Plasma Diagnostics, R. L. Porter, Gary J. Ferland Jul 2007

Revisiting He-Like X-Ray Emission-Line Plasma Diagnostics, R. L. Porter, Gary J. Ferland

Physics and Astronomy Faculty Publications

A complete model of helium-like line and continuum emission has been incorporated into the plasma simulation code Cloudy. All elements between He and Zn are treated, any number of levels can be considered, and radiative and collisional processes are included. This includes photoionization from all levels, line transfer, including continuum pumping and destruction by background opacities, scattering, and collisional processes. The model is calculated self-consistently along with the ionization and thermal structure of the surrounding nebula. The result is a complete line and continuum spectrum of the plasma. Here we focus on the ions of the He I sequence and …


The Mid-Infrared Emission Of M87, Eric S. Perlman, R. E. Mason, Christopher Packham, N. A. Levenson, Moshe Elitzur, Justin J. Schaefer, Masatoshi Imanishi, William B. Sparks, James Radomski Jul 2007

The Mid-Infrared Emission Of M87, Eric S. Perlman, R. E. Mason, Christopher Packham, N. A. Levenson, Moshe Elitzur, Justin J. Schaefer, Masatoshi Imanishi, William B. Sparks, James Radomski

Physics and Astronomy Faculty Publications

We discuss Subaru and Spitzer Space Telescope imaging and spectroscopy of M87 in the mid-infrared (mid-IR) from 5 to 35 μm. These observations allow us to investigate mid-IR emission mechanisms in the core of M87 and to establish that the flaring, variable jet component HST-1 is not a major contributor to the mid-IR flux. The Spitzer data include a high signal-to-noise ratio 15-35 μm spectrum of the knot A/B complex in the jet, which is consistent with synchrotron emission. However, a synchrotron model cannot account for the observed nuclear spectrum, even when contributions from the jet, necessary due …


Optically Thick [O I] And [C Ii] Emission Toward Ngc 6334a, N. P. Abel, A. P. Sarma, Thomas H. Troland, Gary J. Ferland Jun 2007

Optically Thick [O I] And [C Ii] Emission Toward Ngc 6334a, N. P. Abel, A. P. Sarma, Thomas H. Troland, Gary J. Ferland

Physics and Astronomy Faculty Publications

This work focuses on [O I] and [C II] emission toward NGC 6334A, an embedded H+ region/PDR only observable at infrared or longer wavelengths. A geometry in which nearly all the emission escapes out the side of the cloud facing the stars, such as Orion, is not applicable to this region. Instead, we find the geometry to be one in which the H+ region and associated PDR is embedded in the molecular cloud. Constant-density PDR calculations are presented which predict line intensities as a function of AV [or N(H)], hydrogen density (nH), and …