Digital Commons Network^™

Asymmetric Localizations Of Lin-17/Fz And Mig-5/Dsh Are Involved In The Asymmetric B Cell Division In C. Elegans, Mingfu Wu, Michael A. Herman

School of Biological Sciences: Faculty Publications

LIN-44/Wnt and LIN-17/Frizzled (Fz) function in a planar cell polarity (PCP)-like pathway to regulate the asymmetric B cell division in Caenorhabditis elegans. We observed asymmetric localization of LIN-17/Frizzled (Fz) and MIG-5/Disheveled (Dsh) during the B cell division. LIN-17∷GFP was asymmetrically localized within the B cell prior to and after the B cell division and correlated with B cell polarity. Asymmetric localization of LIN-17∷GFP was dependent upon LIN-44/Wnt and MIG-5/Dsh function. The LIN-17 transmembrane domain and a portion of the cysteine-rich domain (CRD) were required for LIN-17 function and asymmetric distribution to the B cell daughters, while the conserved KTXXXW …

Spatiotemporal Variations In Growing Season Exchanges Of Co2, H2o, And Sensible Heat In Agricultural Fields Of The Southern Great Plains, Marc L. Fischer, Dave P. Billesbach, Joseph A. Berry, William J. Riley, Margaret S. Torn

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Climate, vegetation cover, and management create finescale heterogeneity in unirrigated agricultural regions, with important but not well quantified consequences for spatial and temporal variations in surface CO2, water, and heat fluxes. Eddy covariance fluxes were measured in seven agricultural fields—comprising winter wheat, pasture, and sorghum—in the U.S. Southern Great Plains (SGP) during the 2001–03 growing seasons. Land cover was the dominant source of variation in surface fluxes, with 50%–100% differences between fields planted in winter–spring versus fields planted in summer. Interannual variation was driven mainly by precipitation, which varied more than twofold between years. Peak aboveground biomass and growing season …

Evolutionary Endocrinology: The Developing Synthesis Between Endocrinology And Evolutionary Genetics, Anthony J. Zera, Lawrence G. Harshman, Tony D. Williams

Anthony Zera Publications

A productive synthesis of endocrinology and evolutionary genetics has occurred during the past two decades, resulting in the first direct documentation of genetic variation and correlation for endocrine regulators in nondomesticated animals. In a number of insect genetic polymorphisms (dispersal polymorphism in crickets, butterfly wing-pattern polymorphism), blood levels of ecdysteroids and juvenile hormone covary with morphology, development, and life history. Genetic variation in insulin signaling may underlie life history trade-offs in Drosophila. Vertebrate studies identified variation in brain neurohormones, bone-regulating hormones, and hormone receptor gene sequences that underlie ecologically important genetic polymorphisms. Most work to date has focused on genetically …

Low-Energy Electron Capture By 6-Aza-2-Thiothymine: Investigations By Electron Attachment And Electron Transmission Spectroscopies, Stanislav A. Pshenichnyuk, Gordon A. Gallup, Paul Burrow

Paul Burrow Publications

The interaction of low-energy (0-10 eV) electrons with 6-aza-2-thiothymine is investigated in the gas phase by studies of sharp structure in the total electron scattering cross section and by mass analysis of the stable or long-lived negative ions produced by electron attachment. The most efficient fragmentation process, occurring at 0.15 eV, involves the ejection of a closed-shell neutral molecule (CH₃CN). Ab initio calculations support our proposal that this process leads to ring closure to form a stable four-member heterocyclic anion. A long-lived parent anion with an approximate lifetime of 75 microseconds is observed near zero electron energy, and …

Parasitism Of Hylodes Phyllodes (Anura: Cycloramphidae) By Hannemania Sp. (Acari: Trombiculidae) In An Area Of Atlantic Forest, Ilha Grande, Southeastern Brazil, F. H. Hatano, Donald Gettinger, M. Van Sluys, C. F. D. Rocha

Harold W. Manter Laboratory of Parasitology: Faculty Publications

We studied some parameters of the parasitism by the mite Hannemania sp. on the endemic frog Hylodes phyllodes in the Atlantic Forest of Ilha Grande (Rio de Janeiro State, Brazil). Prevalence, mean abundance, mean intensity and total intensity of infestation, body regions infected, and host sexual differences in parasitism rate of the larvae of Hannemania sp. on individuals of H. phyllodes were assessed. Prevalence was 86.5 % (N = 37; total of 1,745 larvae of Hannemania sp) for male hosts and 91.7 % (N =12; total of 330 larvae) for female hosts, with no significant difference between the sexes. Overall …

Eastward Ho: Phylogeographical Perspectives On Colonization Of Hosts And Parasites Across The Beringian Nexus [Guest Editorial], Eric Waltari, Eric P. Hoberg, Enrique P. Lessa, Joseph A. Cook

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The response of Arctic organisms and their parasites to dramatic fluctuations in climate during the Pleistocene has direct implications for predicting the impact of current climate change in the North. An increasing number of phylogeographical studies in the Arctic have laid a framework for testing hypotheses concerning the impact of shifting environmental conditions on transcontinental movement. We review 35 phylogeographical studies of trans-Beringian terrestrial and freshwater taxa, both hosts and parasites, to identify generalized patterns regarding the number, direction and timing of trans-continental colonizations. We found that colonization across Beringia was primarily from Asia to North America, with many events …

Antenatal Risk Factors, Cytokines And The Development Of Atopic Disease In Early Childhood, Esther K. Chung, Rachel L. Miller, Michael T. Wilson, Stephen J. Mcgeady, Jennifer F. Culhane

Department of Pediatrics Faculty Papers

Atopic diseases are complex entities influenced by an array of risk factors including genetic predisposition, environmental allergens, antenatal exposures, infections and psychosocial factors. One proposed mechanism by which these risk factors contribute to the development of atopic disease is through alterations in the production of T helper type 1 (Th1) and type 2 (Th2) cytokines. The objectives of this review are to discuss antenatal exposures that are associated with pediatric atopic diseases, to discuss the influence of the intrauterine environment on neonatal immune responses, to provide an overview of the Th1 and Th2 pathways and how they relate to atopic …

Rapid Assessment Of Insect Fragments In Flour Milled From Wheat Infested With Known Densities Of Immature And Adult Sitophilus Oryzae (Coleoptera: Curculionidae), Michael D. Toews, Joel Perez-Mendoza, James E. Throne, Floyd E. Dowell, Elizabeth Maghirang, Frank H. Arthur, James F. Campbell

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Milling wheat, Triticum aestivum L., infested with low densities of internal feeding insects can result in flour containing insect fragments. The Food and Drug Administration (FDA) enforces a standard or defect action level stating that a maximum of 75 insect fragments per 50 g of flour is allowed. However, the relationship between level of infestation and number of resulting fragments is not well documented, and a more rapid method for enumerating insect fragments is needed. We characterized the number of insect fragments produced from milling small lots of wheat spiked with known densities and life stages of Sitophilus oryzae (L.) …

Chlorophacinone Baiting For Belding’S Ground Squirrels, Craig A. Ramey, George H. Matschke, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

The efficacy of using 0.01% chlorophacinone on steam-rolled oat (SRO) groats applied in CA alfalfa by spot-baiting/hand baiting around burrow entrances (~11.5 g) to control free-ranging Belding's ground squirrels (Spermophilus beldingi) were compared in 6 randomly assigned square treatment units (TUs). Four TUs were given the rodenticide and 2 treated with placebo bait. Each TU was a 0.4 ha square surrounded by a similarly treated 5.5 ha square buffer zone. Baits were applied on May 13 and re-applied, on May 20 and May 22, after 7 days of un-forecasted cool wet weather greatly reduced their above ground activity. Pesticide (EPA …

Hereditary Hemorrhagic Telangiectasia. Genetics, Pathogenesis, Clinical Manifestation And Management, Manfred Stuhrmann, El-Harith A. El-Harith

Saudi Medical Journal

Hereditary hemorrhagic telangiectasia HHT, Morbus Osler or Osler-Weber-Rendu syndrome OMIM 187300, is an autosomal dominant disorder characterized by epistaxis, telangiectasia, multi-systemic vascular dysplasia and clinical presentation of wide variation. The pathogenesis involves dilated post-capillary venules or telangiectases in the mucus membrane of various organs as well as larger arteriovenous malformations. Genetic heterogeneity of HHT is confirmed; 2 disease loci, ACVRL1 and ENG genes, have been identified and characterized. The 2 major types of the disease, HHT1 and HHT2, are attributed to mutations in the ENG and ACVRL1 genes. ENG and ACVRL1 genes code for proteins, namely endoglin and activin-receptor-like kinase …

Pattern Of Rheumatic Heart Disease In Southern Yemen, Hussein K. Saleh

Saudi Medical Journal

OBJECTIVE: To determine the pattern of rheumatic heart disease in Aden city and surrounding areas by assessing its frequency distribution, severity and complications. METHODS: We conducted this research in a sole regional echocardiographic department for Southern Yemen governorates at a referral hospital located in Aden city, from January 1999 to December 2003. It was a retrospective study focused on echocardiographic findings in 805 patients affected by rheumatic heart disease. RESULTS: Out of 805 patients, 383 (47.6%) were male and 422 (52.4%) were female (age range, 4-70 years; mean age, 28.6 ± 14.5). Heart valve damage was distributed among patients as …

Bk Virus Infection In A Renal Transplant Saudi Child, Mohamed Maghrabi, Dalia Marwan, Abimbola O. Osoba

Saudi Medical Journal

BK human polyomavirus BKV causes an asymptomatic primary infection in children, but later, establishes latency mainly in the urinary tract. Virus-host interactions influencing persistence and pathogenicity are not well-understood. We present here a 12-year-old Saudi boy, who had renal transplant in Egypt. Seven months later, he was admitted to our Pediatric Nephrology Unit as a case of renal impairment. He developed BKV infection, diagnosed and successfully managed in our hospital. This case demonstrates the expanding clinical importance of BKV in a post renal transplant patient. This virus can be detected in transitional cells in the urine decoy cells using cytology. …

The Role Of B2-Glycoprotein I In Homeostatis, Frederic Lin

Doctoral

B2-glycoprotein I (B2GPI) is a phospholipid-binding protein of 326 amino acids found in plasma at a concentration of approx. 180 ug/ml. It has a sequence of positively charged amino acids located at the carboxy terminus that mediates anionic phospholipid binding. B2GPI is suspected to have a role in inhibition of thrombosis. This suspicion is reinforced by the observation that B2GPI is the major target for autoantibodies in the antiphospholipid syndrome. However, little is known about circulating levels of the protein in common thrombotic diseases of inflammation. In the first part of this thesis, we developed a sensitive sandwich-direct ELISA for …

Development Of A Novel Modular Mid-Infrared Sensor For The In-Situ Detection Of The Btex Compounds In Water, Raymond Mccue

Doctoral

This research thesis describes the design, construction and testing of a novel modular mid-infrared fibre optic sensing system for the detection of hydrocarbons in water. It is the adverse effects to these hydrocarbon pollutants on flora and fauna that has led to the development of sensing systems for their detection and quantification. The key sensor design feature, its modularity, utilises simple low cost commercially available optical components, which are inherently suited to construct compact rugged sensing systems to perform in-situ measurements which are ideally preferred for environmental sensing. The various laboratory-based prototypes constructed weee calibrated for two target analytes over …

Adolescent Sexual Onset: An Intergenerational Analysis, Katherine Johnson, Kimberly A. Tyler

Department of Sociology: Faculty Publications

Adolescents have begun to initiate sexual activity at increasingly early ages in the past few decades. Using a sample of 2,494 adolescents from the National Longitudinal Survey of Youth (NLSY97), structural and parental process variables were examined in the prediction of sexual onset. Results indicated that the age at which youth initiate sexual intercourse is related to the structural characteristics of their grandmothers and mothers, as well as puberty, gender, and race. There is support for partial mediation of the effects of these grandmother characteristics via mother characteristics and parental process. Results are discussed within the framework of the life …

Structure And Biosynthesis Of Heat-Stable Antifungal Factor (Hsaf), A Broad-Spectrum Antimycotic With A Novel Mode Of Action, Fengan Yu, Kathia Zaleta-River, Xiangcheng Zhu, Justin Huffman, Jeffrey C. Millet, Steven D. Harris, Gary Y. Yuen, Xing-Cong Li, Liangcheng Du

Department of Chemistry: Faculty Publications

A screen for antifungal compounds from Lysobacter enzymogenes strain C3, a bacterial biological control agent of fungal diseases, has previously led to the isolation of heat-stable antifungal factor (HSAF). HSAF exhibits inhibitory activities against a wide range of fungal species and shows a novel mode of antifungal action by disrupting the biosynthesis of a distinct group of sphingolipids. We have now determined the chemical structure of HSAF, which is identical to that of dihydromaltophilin, an antifungal metabolite with a unique macrocyclic lactam system containing a tetramic acid moiety and a 5,5,6-tricyclic skeleton. We have also identified the genetic locus responsible …

Energy And Environmental Contributions Of Corn-Ethanol, Adam Liska, Kenneth Cassman, Haishun Yang

Adam Liska Papers

Rapid development of regulatory mechanisms to mitigate greenhouse gas (GHG) emissions requires that the biofuel industry employ standard methods to evaluate biofuel systems comprising both crop production systems and biorefineries. Biofuel systems associated with a variety of organic feedstocks have a range of performance capabilities, and recent life-cycle assessment studies of these different systems have used inconsistent methods, leading to confusion about biofuel energy efficiency and GHG mitigation. Hence, there is a critical need for well documented life-cycle metrics for consistent biofuel evaluation that are established and supported by a national or international governing body. Standardization of net energy and …

Plant Mitochondrial Recombination Surveillance Requires Unusual Reca And Muts Homologs, Vikas Shedge, Maria P. Arrieta-Montiel, Alan C. Christensen, Sally Ann Mackenzie

School of Biological Sciences: Faculty Publications

For >20 years, the enigmatic behavior of plant mitochondrial genomes has been well described but not well understood. Chimeric genes appear, and occasionally are differentially replicated or expressed, with significant effects on plant phenotype, most notably on male fertility, yet the mechanisms of DNA replication, chimera formation, and recombination have remained elusive. Using mutations in two important genes of mitochondrial DNA metabolism, we have observed reproducible asymmetric recombination events occurring at specific locations in the mitochondrial genome. Based on these experiments and existing models of double-strand break repair, we propose a model for plant mitochondrial DNA replication, chimeric gene formation, …

Parasites, Proteomics And Performance: Effects Of Gregarine Gut Parasites On Dragonfly Flight Muscle Composition And Function, Rudolf J. Schilder, James H. Marden

School of Biological Sciences: Faculty Publications

In previous work, we found that dragonflies infected with gregarine gut parasites have reduced muscle power output, loss of lipid oxidation in their flight muscles, and a suite of symptoms similar to mammalian metabolic syndrome. Here, we test the hypothesis that changes in muscle protein composition underlie the observed changes in contractile performance. We found that gregarine infection was associated with a 10-fold average reduction in abundance of a ~155·kDa fragment of muscle myosin heavy chain (MHC; ~206·kDa intact size). Insect MHC gene sequences contain evolutionarily conserved amino acid motifs predicted for calpain cleavage, and we found that calpain digestion …

Microarray Challenges In Ecology, Jan E. Kammenga, Michael A. Herman, N. Joop Ouborg, Loretta Johnson, Rainer Bretling

School of Biological Sciences: Faculty Publications

Microarrays are used to measure simultaneously the amount of mRNAs transcribed from many genes. They were originally designed for gene expression profiling in relatively simple biological systems, such as cell lines and model systems under constant laboratory conditions. This poses a challenge to ecologists who increasingly want to use microarrays to unravel the genetic mechanisms underlying complex interactions among organisms and between organisms and their environment. Here, we discuss typical experimental and statistical problems that arise when analyzing genome-wide expression profiles in an ecological context. We show that experimental design and environmental confounders greatly influence the identification of candidate genes …

Grânulos De Amido E Fitólitos Em Cálculos Dentários Humanos: Contribuição Ao Estudo Do Modo De Vida E Subsistência De Grupos Sambaquianos Do Litoral Sul Do Brasil, Verônica Wesolowski, Sheila Maria Ferraz Mendonça De Souza, Karl Reinhard, Gregório Ceccantini

Karl Reinhard Publications

Este artigo tem por objetivo apresentar os resultados da recuperação e análise de micro-vestígios vegetais retidos em cálculos dentários de grupos de pescadores-coletores do litoral sul do Brasil. Apresenta também os resultados das relações mantidas entre grânulos de amido e cárie, e entre fitólitos e desgaste dentário.

Através da dissolução química de cálculos dentários foram recuperados microvestígios vegetais em todos os indivíduos estudados. Foi evidenciado o consumo de alimentos amiláceos em todas as séries esqueléticas estudadas, demonstrando independência entre dieta com aporte de produtos vegetais e utilização de cerâmica. Foram encontrados resultados sugestivos de padrões de escolha de alimentos diferenciados …

Nebraska Cooperative Fish And Wildlife Research Unit: Report Of Activities October 2006 – October 2007, Craig R. Allen, Kevin L. Pope

School of Natural Resources: Faculty Publications

INTRODUCTION 1
PERSONNEL AND COOPERATORS 3
Unit Personnel 3
Coordinating Committee Members 5
Cooperators 6
MILESTONES 9
PROJECTS IN FISHERY SCIENCE 11
Impact of White Perch on Walleye at Branched Oak and Pawnee Reservoirs 13
Predators of White Perch at Branched Oak and Pawnee Reservoirs 14
Recruitment of Walleye and White Bass in Irrigation Reservoirs 15
PROJECTS IN WILDLIFE SCIENCE 17
Amphibian Monitoring Techniques (in Relation to Wetland Qualities and the Surrounding Landscape
– Rainwater Basin Region) 19
Assessing Local and Regional Variability in Productivity and Fidelity of Grassland Birds on National
Park Service Units in the Great Plains 20 …

How Will Global Climate Change Affect Parasite-Host Assemblages?, Eric P. Hoberg, Daniel R. Brooks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Parasites are integral components of the biosphere. Host switching correlated with events of episodic climate change is ubiquitous in evolutionary and ecological time. Global climate change produces ecological perturbations, which cause geographical and phenological shifts, and alteration in the dynamics of parasite transmission, increasing the potential for host switching. The intersection of climate change with evolutionary conservative aspects of host specificity and transmission dynamics, called ecological fitting, permits emergence of parasites and diseases without evolutionary changes in their capacity for host utilization.

Nearctic Shrews, Sorex Spp., As Paratenic Hosts Of Soboliphyme Baturini (Nematoda: Soboliphymidae), S. V. Karpenko, N. E. Dokuchaev, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Third-stage larvae (L3) of Soboliphyme baturini were discovered for the first time in shrews, Sorex cinereus and Sorex tundrensis from Alaska and the Nearctic. Shrews were found to be infected with L3 at Suloia Lake, southeastern Alaska, Togiak National Wildlife Refuge, southwestern Alaska, and at the Yukon-Charley Rivers National Preserve near the Yukon-Alaska border. Larvae in shrews from Alaska were morphologically indistinguishable from those known in both insectivores and arvicoline rodents from Russia. The occurrence of S. baturini in Alaskan insectivores further establishes shrews as important hosts in the transmission of S. baturini among mustelids and other carnivores and indicates …

First Record Of Alcataenia Larina Larina (Cestoda: Dilepididae) In Atlantic Puffins (Aves, Alcidae, Fratercula Arctica) From Newfoundland, Canada, Sabir B. Muzaffar, Eric P. Hoberg, Ian L. Jones

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The tapeworm Alcataenia larina (Cestoda: Cyclophyllidea: Dilepididae) is a parasite of gulls (Laridae) with a Holarctic distribution in oceanic and littoral habitats. Two subspecies Alcataenia larina pacifica and Alcataenia larina larina are recognized with the former occurring in the North Pacific basin and the latter in the North Atlantic. Alcids serve as incidental hosts for both species and infections are generally rare, usually involving few specimens. We report A. l. larina in Atlantic puffins (Fratercula arctica) collected from the Bay of Exploits, Newfoundland. The 14 strobilate and early gravid specimens were clearly distinguishable from the closely related Alcataenia …

Introduction Scanning Probe Microscopy Techniques For Electrical And Electromechanical Characterization, Sergei Kalinin, Alexei Gruverman

Alexei Gruverman Publications

Progress in modem science is impossible without reliable tools for characterization of structural, physical, and chemical properties of materials and devices at the micro-, nano-, and atomic scale levels. While structural information can be obtained by such established techniques as scanning and transmission electron microscopy, high-resolution examination of local electronic structure, electric potential and chemical functionality is a much more daunting problem. Local electronic properties became accessible after the development of Scanning Tunneling Microscopy by G. Binnig and H. Rohrer in 1981 at IBM Zurich 25 years ago-an invention that earned its authors the Nobel Prize in Physics five years …

Genetic Analysis Of A Novel Alaska Barley Yellow Dwarf Virus In The Family Luteoviridae, N.L. Robertson, Roy C. French

Department of Plant Pathology: Faculty Publications

A new plant virus belonging to the family Luteoviridae and isolated from diseased oat (Avena sativa L.) plants was discovered in Alaska in 2003. Even though plants with red/orange leaves were indicative of barley yellow dwarf disease, they were not reactive to specific antibodies corresponding to barley yellow dwarf virus (BYDV)-MAV, -PAV, -SGV, and cereal yellow dwarf virus-RPV from enzyme-linked immunosorbent assays (ELISA). An alternative RT-PCR assay that incorporated Shu-F/Yan-R primers for detection of BYDV-MAV, -PAS, -PAV, and SGV was effective in producing ~830-nt fragments that contained genomic sequences to the 3’-terminus of the polymerase gene (ORF 2), the …

Personal, Interpersonal, And Political Temperaments, John Alford, John R. Hibbing

Department of Political Science: Faculty Publications

Are political liberals generous? Are political conservatives conscientious? Are generous people personally agreeable? Research in behavioral genetics and elsewhere increasingly indicates a biological basis for the manner in which people behave in personal, interpersonal, and political situations, but this biological basis does not mean behavior in these three very different contexts is correlated. In this article, using an original data set obtained from nearly three hundred subjects, the authors are able to test for the degree to which personal, interpersonal, and political temperaments are related. As expected, the overall correlations are quite low. Standard personality traits do not predict political …

The Biology Of Political Behavior: An Introduction, John R. Hibbing, Kevin B. Smith

Department of Political Science: Faculty Publications

A broad cross-section of the social sciences is increasingly turning to biology and evolutionary theory to help explain human behavior. Political science is a notable exception to this trend, even though there are sound conceptual reasons for expecting biological processes to play an important role in explaining political behavior. While agreeing with the conceptual arguments, the authors believe original empirical research is the most persuasive means of convincing political science to incorporate biology in explanations of political behavior. Techniques developed in neuroscience, behavioral genetics, agent-based simulation, experimental economics, and other fields offer exciting research opportunities to explore questions of central …

Mist Netting Bias, Species Accumulation Curves, And The Rediscovery Of Two Bats On Montserrat (Lesser Antilles), Roxanne Larsen, Karen A. Boegler, Hugh H. Genoways, Will P. Masefield, Ronan A. Kirsch, Scott C. Pedersen

University of Nebraska State Museum: Mammalogy Papers

Mist nets are commonly used to survey bat populations and to estimate bat biodiversity, but several studies have found that mist net capture data and methods are biased due to a number of factors, including size and placement of nets, and the frequency at which investigators check their nets. Despite the wealth of literature and anecdotal reports, few investigators have quantified the interactions of bats with mist nets directly. We employed night vision camcorders to monitor bat behavior when bats encountered a mist net and then utilized these data to reevaluate years of survey data collected on Montserrat, Lesser Antilles. …