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Can Environmental Variation Generate Positive Indirect Effects In A Model Of Shared Predation?, Chad Brassil

School of Biological Sciences: Faculty Publications

Classic models of apparent competition predict negative indirect effects between prey with a shared enemy. If predator per capita growth rates are nonlinear, then endogenously generated periodic cycles are predicted to generate less negative or even positive indirect effects between prey. Here I determine how exogenous mechanisms such as environmental variation could modify indirect effects. I find that exogenous variation can have a broader range of effects on indirect interactions than endogenously generated cycles. Indirect effects are altered by environmental variation even in simple models for which the per capita growth rate of the predator species is a linear function …

Regulation Of Mercury Resistance In The Crenarchaeote Sulfolobus Solfataricus, James Schelert, Melissa Drozda, Vidula Dixit, Amanda Dillman, Paul H. Blum

School of Biological Sciences: Faculty Publications

Mercuric ion, Hg(II), inactivates generalized transcription in the crenarchaeote Sulfolobus solfataricus. Metal

challenge simultaneously derepresses transcription of mercuric reductase (merA) by interacting with the

archaeal transcription factor aMerR. Northern blot and primer extension analyses identified two additional

Hg(II)-inducible S. solfataricus genes, merH and merI (SSO2690), located on either side of merA. Transcription

initiating upstream of merH at promoter merHp was metal inducible and extended through merA and merI,

producing a merHAI transcript. Northern analysis of a merRA double mutant produced by linear DNA

recombination demonstrated merHp promoter activity was dependent on aMerR to overcome Hg(II) …

Anatomy And Physiology Of Giant Neurons In The Antenniform Leg Of The Amblypygid Phrynus Marginemaculatus, A. J. Spence, Eileen Hebets

Eileen Hebets Publications

Amblypygids have modified front legs that are not used for locomotion, but rather to probe the environment in the manner of antennae. These elongate, motile sense organs are referred to as antenniform legs. We have found remarkable replication in structure and function of giant neurons in the antenniform leg of the amblypygid Phrynus marginemaculatus C.L. Koch 1841 when compared with other amblypygids. These neurons have such large diameter axons (several μm) that their action potentials can be recorded outside the cuticle. Their cell bodies are found in the periphery, in the distal-most segments of the antenniform leg, centimeters away from …

Regional Seismic Song Differences In Sky Island Populations Of The Jumping Spider Harbonattus Pugillis Griswold (Araneae, Salticidae), Damian O. Elias, Eileen Hebets, Ronald R. Hoy, Wayne P. Maddison, Andrew C. Mason

Eileen Hebets Publications

Jumping spiders have long been used as model organisms to study visual communication. However, recent studies documenting the presence of intricate multicomponent seismic songs during courtship displays suggest an important role of seismic communication as well. Given the relatively recent focus on seismic communication, the extent to which seismic songs vary among jumping spider species or even among populations remains poorly understood. Here, we use the extensively studied Habronattus pugillis Griswold 1987 complex to explore putative seismic song diversity among males from isolated populations. H. pugillis populations have been studied extensively because of the tremendous diversification of male visual secondary …

Superoxide Dismutase Activities In Long-Lived Drosophila Melanogaster Females: Chico1 Genotypes And Dietary Dilution, Hadise Kabil, Linda Partridge, Lawrence G. Harshman

Lawrence G. Harshman Publications

Superoxide dismutase (SOD) activities were determined for dietary dilution conditions that extend the life span of Drosophila melanogaster. The hypothesis motivating this research was that elevated SOD activity is associated with increased life span resulting from flies being held on a restricted diet. SOD activities were also measured for chico¹ which is a mutation in the insulin receptor substrate protein gene associated with life span extension. This allowed us to confirm the results of (Clancy et al. 2001) and extend the results by measuring CuZn SOD and Mn SOD activities in addition to the previously determined overall SOD activity. …

A Quantitative Trait Locus Analysis Of Natural Genetic Variation For Drosophila Melanogaster Oxidative Stress Survival, Yue Wang, David Pot, Stephen D. Kachman, Sergey V. Nuzhdin, Lawrence G. Harshman

Lawrence G. Harshman Publications

Little is known about natural genetic variation for survival under oxidative stress conditions or whether genetic variation for oxidative stress survival is associated with that for life-history traits. We have investigated survival in a high-oxygen environment at 2 adult densities using a set of re-combinant inbred lines (RILs) isolated from a natural population of Drosophila melanogaster. Female and male oxidative stress survival was highly correlated. Quantitative trait loci (QTLs) for oxidative stress survival were identified on both autosomes. These QTLs were sometimes sex or density spe-cific but were most often not. QTLs were identified that colocalize to the same …

Hyla Squirella (Squirrel Treefrog): Refugia., Louis A. Somma, David Serrano

Papers in Herpetology

HYLA SQUiREUA (Squirrel Treefrog). REFUGIA. Entomologists commonly use trap-nests to monitor cavity-nesting Hymenoptera. These trap-nests consist of 5 x 10 cm pine timber cut into 12-cm lengths. Five lengths are then stacked and strapped together. Each pIece of timber is predrilled in each side to have either a 3.2, 4.8, 6.4, 7.9, or 12.7 Iiundiameterhole, 8 cmindepth. Thus, each trap-nest consisted of five pieces of wood containing 2 holes of each diameter. They are suspended with wire from tree trunks and branches. We set these wooden traps (N = 10) at Devil's Millhopper Geological State Park, Gainesville, Alachua Co., Florida, …

Fire Does Not Alter Vegetation In Infertile Prairie, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

The paradigm in prairie ecology is that fire is one of the key factors deter-mining vegetation composition. fire can impact grassland ecosystems in various ways, including changing plant species composition and inducing nitro-gen loss. I found that 17 years of different burning frequencies in infertile grassland had only a minor impact on the vegetation composition and diversity. The only major impact from increasing the frequency of fires was a decrease of Poa pratensis abundance. However, other plant species did not r-spond to the change in Poa abundance. This result contrasts with previous studies in savannas and more productive grasslands, where …

Premature Induction Of An Immunosuppressive Regulatory T Cell Response During Acute Simian Immunodeficiency Virus Infection, Jacob D. Estes, Qingsheng Li, Matthew R. Reynolds, Stephen W. Wietgrefe, Lijie Duan, Timothy Schacker, Louis J. Picker, David I. Watkins, Jeffrey D. Lifson, Cavan Reilly, John V. Carlis, Ashley T. Haase

Qingsheng Li Publications

Here we report the results of an investigation into the possibility that one mechanism responsible for the establishment of persistent human immunodeficiency virus infection is an early regulatory T (T_reg) cell response that blunts virus- specific responses. Using the simian immunodeficiency virus (SIV)–infected rhesus macaque model, we show that, indeed, viral replication and immune activation in lymphatic tissue drive a premature immunosuppressive response, with dramatic increases in the frequencies of CD4⁺CD25⁺FOXP3⁺ Treg cells, transforming growth factor–β1⁺ cells, interleukin–10+ cells, and indoleamine 2,3-dioxygenase+CD3⁺ cells.When we compared SIV infection with rhesus cytomegalovirus (RhCMV) …

Invasive Insect Abundance Varies Across The Biogeographic Distribution Of A Native Host Plant, Tatyana A. Rand, Svata M. Louda

Svata M. Louda Publications

Studies of biogeographic variation in species abundances are fundamental to understanding and predicting the impacts of invasive exotic species. We quantified the abundance of the introduced and now invasive biocontrol weevil, Rhinocyllus conicus, on a newly adopted native host plant, Cirsium canescens (Platte thistle), across the plant’s distributional range. We used regression and structural equation analyses to examine variation in weevil abundance at 92–108 sites over three years in relation to variation in abiotic and biotic parameters hypothesized to be important in insect or plant dynamics and distribution. We found that R. conicus now occurs throughout the majority of …

Determination Of Mrna Half-Lives In Candida Albicans Using Thiolutin As A Transcription Inhibitor, Bessie W. Kebaara, Lindsey E. Nielsen, Kenneth Nickerson, Audrey L. Atkin

Kenneth Nickerson Papers

A method for determining mRNA half-lives in the polymorphic fungus Candida albicans is described. It employs growth in a defined medium, the inhibition of transcription with thiolutin (10–20 μg/mL), and quantitative Northern blotting. The method is effective for the A72, SC5314, and CAI-4 strains of C. albicans, and for mRNAs that have a wide variety of decay rates and steady-state abundances. The range of half-lives detected (from 4–168 min) shows that this method is effective for mRNAs with widely varying half-lives. The mRNA decay rates obtained are compared with those for orthologous mRNAs from Saccharomyces cerevisiae. This procedure …

Hen1 Recognizes 21–24 Nt Small Rna Duplexes And Deposits A Methyl Group Onto The 2' Oh Of The 3' Terminal Nucleotide, Zhiyong Yang, Yon W. Ebright, Bin Yu, Xuemei Chen

Bin Yu Publications

microRNAs (miRNAs) and small interfering RNAs (siRNAs) in plants bear a methyl group on the ribose of the 3' terminal nucleotide. We showed previously that the methylation of miRNAs and siRNAs requires the protein HEN1 in vivo and that purified HEN1 protein methylates miRNA/miRNA* duplexes in vitro. In this study, we show that HEN1 methylates both miRNA/miRNA* and siRNA/siRNA* duplexes in vitro with a preference for 21–24 nt RNA duplexes with 2 nt overhangs. We also demonstrate that HEN1 deposits the methyl group on to the 2' OH of the 3' terminal nucleotide. Among various modifications thatcanoccuronthe ribose of …

Kenneth Bloom: Publications List Through January 2006

Kenneth Bloom Publications

Lists 280 publications from arXiv, Physical Review Letters, Physical Review D, Physics Letters B, and IEEE Transactions on Nuclear Science. Includes works in press as of January 2006.

Erratum: Dynamics Of Filament Formation In A Kerr Medium [Phys Rev. A 71, 063811 (2005)], Martin Centurion, Ye Pu, Mankei Tsang, Demetri Psaltis

Martin Centurion Publications

We have found an error in this paper -- [Phys Rev. A 71, 063811 (2005)]. In our calculation of the intensity threshold for breakdown in CS₂ we erroneously used the ionization energy of molecular CS₂ (10.08 eV). The correct value should be 3.3 eV, the band gap energy of liquid CS₂ . Using the band gap energy, nonlinear absorption will be a three-photon process, and the calculated breakdown threshold becomes 8.5 × 10¹¹ W/cm² (as opposed to the value of 2×10¹³ W/cm² reported previously). Multiphoton absorption and plasma defocusing could then become significant …

First Report Of Mites And Fleas Associated With Sigmodontine Rodents From Corrientes Province, Argentina, Marcela Lareschi, Donald Gettinger, Santiago Nava, Agustín Abba, Mariano L. Merino

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Fleas (Insecta: Siphonaptera) and mesostigmate mites (Acari: Laelapidae) are common ectoparasitic associates of sigmodontine rodents in the Neotropics of South America. In Argentina, most of the research on ectoparasitic arthropods has been carried out on rodents from Buenos Aires Province (Autino and Lareschi, 1998; Lareschi and Mauri, 1998), while only a few small studies have been done in other areas of the country, such as the northwest (Lareschi et al., 2003a), and the Monte Desert Biome in Mendoza Province (Lareschi et al., 2004). Unfortunately, very little information is available from the region between the Paraná and Uruguay rivers in northeastern …

Liberty, Gender, And The Family, Jennifer Mckitrick

Department of Philosophy: Faculty Publications

DISCUSSIONS OF JUSTICE within the classical liberal, libertarian tradition have been universalist. They have aspired to apply to any human community, whatever the makeup of its membership. Certainly some feminists have taken issue with this, arguing that the classical liberal, libertarian understanding of justice fails to address the concerns of women, indeed, does women an injustice. Among these we find Susan Moller Okin, and it will be my task in this essay to explore whether Okin's criticism is well founded. Susan Moller Okin's justice, Gender, and the Family is a landmark feminist discussion of distributive justice that raises issues no …

Parelaphostrongylus Odocoilei In Columbia Black-Tailed Deer From Oregon, Jack A. Mortenson, Arthur Abrams, Benjamin M. Rosenthal, Detiger Dunams, Eric P. Hoberg, Robert J. Bildfell, Richard L. Green

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Documenting the occurrence of Parelaphostrongylus odocoilei has historically relied on the morphological examination of adult worms collected from the skeletal muscle of definitive hosts, including deer. Recent advances in the knowledge of protostrongylid genetic sequences now permit larvae to be identified. Dorsal-spined larvae (DSLs) collected in 2003–2004 from the lung and feces of six Columbian black-tailed deer (Odocoileus hemionus columbianus) from Oregon were characterized genetically. The sequences from unknown DSLs were compared to those from morphologically validated adults and larvae of P. odocoilei at both the second internal transcribed spacer (ITS-2) of ribosomal DNA and the mitochondrial cytochrome …

Dissolution Kinetics Of High Explosives Particles In A Saturated Sandy Soil, Matthew C. Morley, Hiroshi Yamamoto, Gerald E. Speitel, Jr., Jay Clausen

Department of Civil and Environmental Engineering: Faculty Publications

Solid phase high explosive (HE) residues from munitions detonation may be a persistent source of soil and groundwater contamination at military training ranges. Saturated soil column tests were conducted to observe the dissolution behavior of individual components (RDX, HMX, and TNT) from two HE formulations (Comp B and C4). HE particles dissolved readily, with higher velocities yielding higher dissolution rates, higher mass transfer coefficients, and lower effluent concentrations. Effluent concentrations were below solubility limits for all components at superficial velocities of 10–50 cm day^-1. Under continuous flow at 50 cm day^-1, RDX dissolution rates from Comp …

Detection Of Inclement Weather Conditions At A Signalized Intersection Using A Video Image Processing Algorithm, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta, James V. Krogmeier

Department of Civil and Environmental Engineering: Faculty Publications

Inclement weather conditions like snowfall adversely affect traffic flow characteristics, necessitating a change in parameters that define the operation of a signalized intersection. A weather-based timing plan selection is needed to maintain a desirable level of operational efficiency. Automatic implementation of weather-based timing at intersections requires accurate and timely detection of snowfall. This paper presents a snow detection algorithm that uses live video feed obtained from a video image vehicle detection system present at an intersection.

Stochastic Algorithm For Improved Operations At Isolated High Speed Intersections, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Department of Civil and Environmental Engineering: Faculty Publications

The current practice of specifying simultaneous gap out logic at isolated high speed signalized intersections places constraints on the signal controller logic that cannot be satisfied under high congestion level. Further, it often results in degraded signal efficiency and dilemma zone protection. A stochastic approach is proposed in this paper with the objective of increasing safety and efficiency at these intersections.

Fast-Nmr - Functional Annotation Screening Technology Using Nmr Spectroscopy, Kelly A. Mercier, Michael Baranski, Viswanathan Ramanathan, Peter Z. Revesz, Rong Xiao, Gaetano T. Montelione, Robert Powers

Robert Powers Publications

An abundance of protein structures emerging from structural genomics and the Protein Structure Initiative (PSI) are not amenable to ready functional assignment because of a lack of sequence and structural homology to proteins of known function. We describe a high-throughput NMR methodology (FAST-NMR) to annotate the biological function of novel proteins through the structural and sequence analysis of protein-ligand interactions. This is based on basic tenets of biochemistry where proteins with similar functions will have similar active sites and exhibit similar ligand binding interactions, despite global differences in sequence and structure. Protein-ligand interactions are determined through a tiered NMR screen …

How To Improve Critical Thinking Skills In The Media Tsrategy Course By Implementing An Online Peer Learning Component, Frauke Hachtmann

College of Journalism and Mass Communications: Faculty Publications

This study addresses how a specific teaching standard set forth by the Accrediting Council on Education in Journalism and Mass Communications (ACEJMC) can be measured in one of the core courses in an accredited advertising program at a large Midwestern university. Specifically, it focuses on how critical thinking skills can be improved using online peer learning in the advertising media strategy course. This study is the result of an inquiry course portfolio the author developed as a fellow of the "Peer Review of Teaching Project."

Prairie Suite: A Celebration, Twyla Hansen, Paul A. Johnsgard

Paul Johnsgard Collection

25 poems by Twyla Hansen, with illustrations by Paul A. Johnsgard, including:

Walk on the Prairie

There is mystery here, in the shapes of grass,
in the dim movements of an inland sea,
connections to an earlier time. Wander barefoot,
hypothesize the dance of millennia, the unbearable
carvings of the built environment, this ragtag escape.

Let its divine simplicity ooze into your pores.
Comb the steel from your hair, blanket your
tongue with orange. Your breathing will slow.
Breathing slow, unbutton the child within.
Give her permission to go fly a kite.

Trends In High Incomes And Behavioral Responses To Taxation: Evidence From Executive Compensation And Statistics Of Income Data, Nada O. Eissa, Seth H. Giertz

Department of Economics: Faculty Publications

This paper examines income trends from 1992 to 2004 and the responsiveness of different income measures to tax changes for corporate executives and for the very highest income U.S. taxpayers. We detail the growth in executive compensation and break down the components of that growth by sources, such as the value of options and stock grants, as well as bonus income. We then examine income trends at various points in the income distribution for executives and for all taxpayers. An empirical strategy similar to that employed by Goolsbee (2000) is then used to examine the responsiveness to tax rates of …

Coupling Between Primary Terrestrial Succession And The Trophic Development Of Lakes At Glacier Bay, Alaska, D. R. Engstrom, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The natural eutrophication of lakes is still an accepted concept in limnology, arising as it does from the earliest efforts to classify lakes and place them in an evolutionary sequence. Recent studies of newly formed lakes at Glacier Bay, Alaska, only partially support this idea, and suggest more variable trends in lake trophic development which are under local (catchment-level) control. Here we use sediment cores from several lakes in Glacier Bay National Park to examine the relationship between successional changes in catchment vegetation and trends in water-column nitrogen (a limiting nutrient) and lake primary production. Terrestrial succession at Glacier Bay …

Isopiestic Measurement Of The Osmotic Coefficients Of Aqueous {Xh2So4 + (1−X)Fe2(So4)3} Solutions At 298.15 And 323.15 K, Mariano Velazquez-Rivera, Donald Palmer, Richard Kettler

Department of Earth and Atmospheric Sciences: Faculty Publications

This study measures the osmotic coefficients of {xH₂SO₄ +(1−x)Fe₂ (SO₄)₃}(aq) solutions at 298.15 and 323.15 K that have ionic strengths as great as 19.3 mol•kg^-1, using the isopiestic method. Experiments utilized both aqueous NaCl and H₂SO₄ as reference solutions. Equilibrium values of the osmotic coefficient obtained using the two different reference solutions were in satisfactory internal agreement. The solutions follow generally the Zdanovskii empirical linear relationship and yield values of a_w for the Fe₂ (SO₄)₃–H₂O binary system at 298.15 …

Reconstructing Sea-Level Change From The Internal Architecture Of Stromatolite Reefs: An Example From The Mesoproterozoic Sulky Formation, Dismal Lakes Group, Arctic Canada, L C. Kah, Julie K. Bartley, Tracy D. Frank, Timothy W. Lyons

Department of Earth and Atmospheric Sciences: Faculty Publications

The Mesoproterozoic Dismal Lakes Group, arctic Canada, contains a relatively thin, yet regionally extensive stromatolitic reef complex that developed subtidally during a major transgression, shoaled to sea level, and was overlain by intertidal to supratidal carbonate and evaporite strata. The September Lake reef complex exhibits a complex internal architecture that records the interaction between stromatolite growth and changes in accommodation space derived from both higher order (4th- or 5th-order, parasequence-scale) changes in sea level and the variable bathymetry of the sea floor. Reef growth, which was initiated during three sea-level cycles, records progressive marine transgression over depositional lows that were …

Saudi Medical Journal. Maintaining The Previous, Achieving More Progress, Saleh M. Al-Deeb

Saudi Medical Journal

No abstract provided.

Molecular Basis Of Breast Cancer, Layla J. Al-Mansouri, Majed S. Alokail

Saudi Medical Journal

Breast cancer is the most frequent cancer in women and represents the second leading cause of cancer death among women after lung cancer. A common phenotypic abnormality of breast cancer cells is dysregulation of cell cycle control. The transformation of normal cell to a cancer cell appears to depend on mutation in genes that normally control cell cycle progression, thus leading to loss of the regulatory cell growth. We summarize here the molecular regulation of mammary carcinoma with regards to the most prominent oncogenes and tumor suppressor genes and their outcome in terms of cellular prognosis, and tumor development.

Echocardiographic Study Of Aortic Root Diameter In Healthy Children, Piraye Kervancioglu, Mehmet Kervancioglu, Cudi M. Tuncer

Saudi Medical Journal

OBJECTIVE: Echocardiography is commonly used to measure the internal diameter of aortic root, which provides the evaluation of aortic root dilatation. Aortic root dilatation provide information concerning prognosis of aortic regurgitation and predisposition to aortic root dissection or rupture. The purpose of the study was to create normal values for aortic root diameters by using echocardiography in healthy children. METHODS: We obtained the aortic root diameters in 229 normal children, aged one day to 15 years by using M-mode echocardiography. We performed the echocardiograms from the Department of Pediatric Echocardiography Laboratory, Medical Faculty, Dicle University, Turkey. We divided the children …