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2015

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Current Understanding Of The Relationship Between Periodontal And Systemic Diseases, Hani H. Mawardi, Lena S. Elbadawi, Stephen T. Sonis Jan 2015

Current Understanding Of The Relationship Between Periodontal And Systemic Diseases, Hani H. Mawardi, Lena S. Elbadawi, Stephen T. Sonis

Saudi Medical Journal

Periodontal disease (PD) is among the most common infectious diseases affecting humans. While the burden of periodontal disease on oral health has been extensively investigated, a possible specific relationship between the disease and systemic health is a relatively new area of interest. More recently it has been suggested that PD has an etiological role in the development of atherosclerotic cardiovascular disease, diabetes mellitus, and preterm low-birth weight, among others. In this review, we critically evaluate the current knowledge on the relation between PD and systemic diseases overall, and specifically with cardiovascular diseases. The best available evidence today suggests that the …


Prognostic Significance And Clinicopathological Features Of Hypoxic Inducible Factor-2alpha Expression In Hepatocellular Carcinoma, Qiyang Yao, Yang Lv, Tingting Pan, Yongju Liu, Jie Ma, Geliang Xu Jan 2015

Prognostic Significance And Clinicopathological Features Of Hypoxic Inducible Factor-2alpha Expression In Hepatocellular Carcinoma, Qiyang Yao, Yang Lv, Tingting Pan, Yongju Liu, Jie Ma, Geliang Xu

Saudi Medical Journal

Objectives: To assess the association between hypoxic inducible factor-2alpha (HIF-2α) and hepatocellular carcinoma (HCC) by meta-analysis. Methods: This study was carried out at Anhui Province Hospital, Hefei, Anhui, China in February 2014. We searched various databases for studies published in English or Chinese up to February 28, 2014. The hazard ratio for overall survival and analyzed odds ratio were combined to evaluate the clinicopathological features of HIF-2α expression in HCC. Results: A total of 7 eligible studies comprising 1066 patients with HCC were identified after our full assessment according to inclusion criteria. All of the patients came from China. The …


New Global Viral Threats, Hakan Erdem, Serhat Ünal Jan 2015

New Global Viral Threats, Hakan Erdem, Serhat Ünal

Saudi Medical Journal

Infectious diseases have caused great catastrophes in human history, as in the example of the plague, which wiped out half of the population in Europe in the 14th century. Ebola virus and H7N9 avian influenza virus are 2 lethal pathogens that we have encountered in the second decade of the 21st century. Ebola infection is currently being seen in West Africa, and H7N9 avian flu appears to have settled in Southeast Asia. This article focuses on the current situation and the future prospects of these potential infectious threats to mankind.


Gestational Diabetes Mellitus, Eman M. Alfadhli Jan 2015

Gestational Diabetes Mellitus, Eman M. Alfadhli

Saudi Medical Journal

Gestational diabetes mellitus (GDM) is the most common medical complication of pregnancy. It is associated with maternal and neonatal adverse outcomes. Maintaining adequate blood glucose levels in GDM reduces morbidity for both mother and baby. There is a lack of uniform strategies for screening and diagnosing GDM globally. This review covers the latest update in the diagnosis and management of GDM. The initial treatment of GDM consists of diet and exercise. If these measures fail to achieve glycemic goals, insulin should be initiated. Insulin analogs are more physiological than human insulin, and are associated with less risk of hypoglycemia, and …


Apparatus, Systems, And Methods For Modular Soft Robots, Stephen A. Morin, Sen Wai Kwok, Robert F. Shepherd, George M. Whitesides Jan 2015

Apparatus, Systems, And Methods For Modular Soft Robots, Stephen A. Morin, Sen Wai Kwok, Robert F. Shepherd, George M. Whitesides

Department of Chemistry: Faculty Publications

Apparatus, Systems, and methods for providing modular soft robots are disclosed. In particular, the disclosed modular soft robot can include a flexible actuator having a plurality of molded flexible units. Each molded flexible unit can include a mechanical connector configured to provide a physical coupling to another molded flexible unit, and the plurality of molded flexible units are arranged to form an embedded fluidic channel. The modular soft robot can also include an inlet coupled to the embedded fluidic channel, where the inlet is configured to receive pressurized or depressurized fluid to inflate or deflate a portion of the flexible …


Dietary Plant Sterol Esters Must Be Hydrolyzed To Reduce Intestinal Cholesterol Absorption In Hamsters, Trevor J. Carden, Jiliang Hang, Patrick Dussault, Timothy P. Carr Jan 2015

Dietary Plant Sterol Esters Must Be Hydrolyzed To Reduce Intestinal Cholesterol Absorption In Hamsters, Trevor J. Carden, Jiliang Hang, Patrick Dussault, Timothy P. Carr

Patrick Dussault Publications

Background: Elevated concentrations of LDL cholesterol are associated with the development of atherosclerosis and therefore are considered an important target for intervention to prevent cardiovascular diseases. The inhibition of cholesterol absorption in the small intestine is an attractive approach to lowering plasma cholesterol, one that is addressed by drug therapy as well as dietary supplementation with plant sterols and plant sterol esters (PSEs).

Objective: This study was conducted to test the hypothesis that the cholesterol-lowering effects of PSE require hydrolysis to free sterols (FSs).

Methods: Male Syrian hamsters were fed atherogenic diets (AIN-93M purified diet containing 0.12% cholesterol and 8% …


Chromatographic Immunoassays: Strategies And Recent Developments In The Analysis Of Drugs And Biological Agents, Ryan E. Matsuda, Elliott Rodriguez, Doddavenkatanna Suresh, David S. Hage Jan 2015

Chromatographic Immunoassays: Strategies And Recent Developments In The Analysis Of Drugs And Biological Agents, Ryan E. Matsuda, Elliott Rodriguez, Doddavenkatanna Suresh, David S. Hage

David Hage Publications

A chromatographic immunoassay is a technique in which an antibody or antibodyrelated agent is used as part of a chromatographic system for the isolation or measurement of a specific target. Various binding agents, detection methods, supports and assay formats have been developed for this group of methods, and applications have been reported that range from drugs, hormones and herbicides to peptides, proteins and bacteria. This review discusses the general principles and applications of chromatographic immunoassays, with an emphasis being given to methods and formats that have been developed for the analysis of drugs and biological agents. The relative advantages or …


Distinct And Cooperative Activities Of Heso1 And Urt1 Nucleotidyl Transferases In Microrna Turnover In Arabidopsis, Bin Tu, Li Liu, Chi Xu, Jixinan Zhai, Shengben Li, Miguel A. Lopez, Yuanyuan Zhao, Yu Yu, Vanitharani Ramachandran, Guodong Ren, Bin Yu, Shigui Li, Blake C. Meyers, Beixin Mo, Xuemei Chen Jan 2015

Distinct And Cooperative Activities Of Heso1 And Urt1 Nucleotidyl Transferases In Microrna Turnover In Arabidopsis, Bin Tu, Li Liu, Chi Xu, Jixinan Zhai, Shengben Li, Miguel A. Lopez, Yuanyuan Zhao, Yu Yu, Vanitharani Ramachandran, Guodong Ren, Bin Yu, Shigui Li, Blake C. Meyers, Beixin Mo, Xuemei Chen

School of Biological Sciences: Faculty Publications

3’ uridylation is increasingly recognized as a conserved RNA modification process associated with RNA turnover in eukaryotes. 2’-O-methylation on the 3’ terminal ribose protects micro(mi)RNAs from 3’ truncation and 3’ uridylation in Arabidopsis. Previously, we identified HESO1 as the nucleotidyl transferase that uridylates most unmethylated miRNAs in vivo, but substantial 3’ tailing of miRNAs still remains in heso1 loss-of-function mutants. In this study, we found that among nine other potential nucleotidyl transferases, UTP:RNA URIDYLYLTRANSFERASE 1 (URT1) is the single most predominant nucleotidyl transferase that tails miRNAs. URT1 and HESO1 prefer substrates with different 3’ end nucleotides in vitro and act …


Synergistic And Independent Actions Of Multiple Terminal Nucleotidyl Transferases In The 3’ Tailing Of Small Rnas In Arabidopsis, Xiaoyan Wang, Shuxin Zhang, Yongchao Dou, Chi Zhang, Xuemei Chen, Bin Yu, Guodong Ren Jan 2015

Synergistic And Independent Actions Of Multiple Terminal Nucleotidyl Transferases In The 3’ Tailing Of Small Rnas In Arabidopsis, Xiaoyan Wang, Shuxin Zhang, Yongchao Dou, Chi Zhang, Xuemei Chen, Bin Yu, Guodong Ren

School of Biological Sciences: Faculty Publications

All types of small RNAs in plants, piwi-interacting RNAs (piRNAs) in animals and a subset of siRNAs in Drosophila and C. elegans are subject to HEN1 mediated 3’ terminal 2’-Omethylation. This modification plays a pivotal role in protecting small RNAs from 3’ uridylation, trimming and degradation. In Arabidopsis, HESO1 is a major enzyme that uridylates small RNAs to trigger their degradation. However, U-tail is still present in null hen1 heso1 mutants, suggesting the existence of (an) enzymatic activities redundant with HESO1. Here, we report that UTP: RNA uridylyltransferase (URT1) is a functional paralog of HESO1. URT1 interacts with AGO1 and …


What Drives Masting? The Phenological Synchrony Hypothesis, Walter D. Koenig, Johannes M.H. Knops, William J. Carmen, Ian S. Pearse Jan 2015

What Drives Masting? The Phenological Synchrony Hypothesis, Walter D. Koenig, Johannes M.H. Knops, William J. Carmen, Ian S. Pearse

School of Biological Sciences: Faculty Publications

Annually variable and synchronous seed production, or masting behavior, is a widespread phenomenon with dramatic effects on wildlife populations and their associated communities. Proximally, masting is often correlated with environmental factors and most likely involves differential pollination success and resource allocation, but little is known about how these factors interact or how they influence seed production. We studied masting in the valley oak (Quercus lobata Nee), a California endemic tree, and report evidence that phenological synchrony in flowering driven by microclimatic variability determines the size of the acorn crop through its effects on pollen availability and fertilization success. These …


Pollen Limitation And Flower Abortion In A Wind-Pollinated, Masting Tree, Ian S. Pearse, Walter D. Koenig, Kyle A. Funk, Mario B. Pesendorfer Jan 2015

Pollen Limitation And Flower Abortion In A Wind-Pollinated, Masting Tree, Ian S. Pearse, Walter D. Koenig, Kyle A. Funk, Mario B. Pesendorfer

School of Biological Sciences: Faculty Publications

Pollen limitation is a key assumption of theories that explain mast seeding, which is common among wind-pollinated and woody plants. In particular, the pollen coupling hypothesis and pollination Moran effect hypothesis assume pollen limitation as a factor that synchronizes seed crops across individuals. The existence of pollen limitation has not, however, been unambiguously demonstrated in wind-pollinated, masting trees. We conducted a two-year pollen supplementation experiment on a masting oak species, Quercus lobata. Supplemental pollen increased acorn set in one year but not in the other, supporting the importance of pollen coupling and pollination Moran effect models of mast seeding. …


Integral Projection Models Show Exotic Thistle Is More Limited Than Native Thistle By Ambient Competition And Herbivory, Brigitte Tenhumberg, Tomomi Suwa, Andrew J. Tyre, F. Leland Russell, Svata M. Louda Jan 2015

Integral Projection Models Show Exotic Thistle Is More Limited Than Native Thistle By Ambient Competition And Herbivory, Brigitte Tenhumberg, Tomomi Suwa, Andrew J. Tyre, F. Leland Russell, Svata M. Louda

School of Biological Sciences: Faculty Publications

Both competitors and natural enemies can limit plant population growth. However, demographic comparisons of the effects of these interactions on introduced versus co-occurring, related native species are uncommon. We asked: (1) does plant competition, insect herbivory, or their combination reduce population growth rate, log λ, of the Eurasian thistle Cirsium vulgare sufficiently to explain its limited invasiveness in western tallgrass prairie; and (2) how do the effects of these interactions compare to those for C. altissimum, its co-occurring, synchronously-flowering native congener? We developed integral projection models (IPMs) to estimate log λ for both species, using parameter estimates from field …


Convergent Evolution Of Hemoglobin Function In High-Altitude Andean Waterfowl Involves Limited Parallelism At The Molecular Sequence Level, Chandrasekhar Natarajan, Joana Projecto-Garcia, Hideaki Moriyama, Roy E. Weber, Violeta Muñoz-Fuentes, Andy J. Green, Cecilia Kopuchian, Pablo L. Tubaro, Luis Alza, Mariana Bulgarella, Matthew M. Smith, Robert E. Wilson, Angela Fago, Kevin G. Mccracken, Jay F. Storz Jan 2015

Convergent Evolution Of Hemoglobin Function In High-Altitude Andean Waterfowl Involves Limited Parallelism At The Molecular Sequence Level, Chandrasekhar Natarajan, Joana Projecto-Garcia, Hideaki Moriyama, Roy E. Weber, Violeta Muñoz-Fuentes, Andy J. Green, Cecilia Kopuchian, Pablo L. Tubaro, Luis Alza, Mariana Bulgarella, Matthew M. Smith, Robert E. Wilson, Angela Fago, Kevin G. Mccracken, Jay F. Storz

School of Biological Sciences: Faculty Publications

A fundamental question in evolutionary genetics concerns the extent to which adaptive phenotypic convergence is attributable to convergent or parallel changes at the molecular sequence level. Here we report a comparative analysis of hemoglobin (Hb) function in eight phylogenetically replicated pairs of high- and low-altitude waterfowl taxa to test for convergence in the oxygenation properties of Hb, and to assess the extent to which convergence in biochemical phenotype is attributable to repeated amino acid replacements. Functional experiments on native Hb variants and protein engineering experiments based on sitedirected mutagenesis revealed the phenotypic effects of specific amino acid replacements that were …


Gillespie Eco-Evolutionary Models (Gems) Reveal The Role Of Heritable Trait Variation In Eco-Evolutionary Dynamics, John Delong, Jean P. Gibert Jan 2015

Gillespie Eco-Evolutionary Models (Gems) Reveal The Role Of Heritable Trait Variation In Eco-Evolutionary Dynamics, John Delong, Jean P. Gibert

School of Biological Sciences: Faculty Publications

Heritable trait variation is a central and necessary ingredient of evolution. Trait variation also directly affects ecological processes, generating a clear link between evolutionary and ecological dynamics. Despite the changes in variation that occur through selection, drift, mutation, and recombination, current ecoevolutionary models usually fail to track how variation changes through time. Moreover, eco-evolutionary models assume fitness functions for each trait and each ecological context, which often do not have empirical validation. We introduce a new type of model, Gillespie eco-evolutionary models (GEMs), that resolves these concerns by tracking distributions of traits through time as ecoevolutionary dynamics progress. This is …


Genetically Based Low Oxygen Affinities Of Felid Hemoglobins: Lack Of Biochemical Adaptation To High-Altitude Hypoxia In The Snow Leopard, Jan E. Janecka, Simone S. E. Nielsen, Sidsel D. Andersen, Federico G. Hoffmann, Roy E. Weber, Trevor Anderson, Jay F. Storz, Angela Fago Jan 2015

Genetically Based Low Oxygen Affinities Of Felid Hemoglobins: Lack Of Biochemical Adaptation To High-Altitude Hypoxia In The Snow Leopard, Jan E. Janecka, Simone S. E. Nielsen, Sidsel D. Andersen, Federico G. Hoffmann, Roy E. Weber, Trevor Anderson, Jay F. Storz, Angela Fago

School of Biological Sciences: Faculty Publications

Genetically based modifications of hemoglobin (Hb) function that increase blood–O2 affinity are hallmarks of hypoxia adaptation in vertebrates. Among mammals, felid Hbs are unusual in that they have low intrinsic O2 affinities and reduced sensitivities to the allosteric cofactor 2,3-diphosphoglycerate (DPG). This combination of features compromises the acclimatization capacity of blood–O2 affinity and has led to the hypothesis that felids have a restricted physiological niche breadth relative to other mammals. In seeming defiance of this conjecture, the snow leopard (Panthera uncia) has an extraordinarily broad elevational distribution and occurs at elevations above 6000 m in the Himalayas. Here, …


Females Sample More Males At High Nesting Densities, But Ultimately Obtain Less Attractive Mates, Robin M. Tinghitella, Chelsea Stehle, Janette W. Boughman Jan 2015

Females Sample More Males At High Nesting Densities, But Ultimately Obtain Less Attractive Mates, Robin M. Tinghitella, Chelsea Stehle, Janette W. Boughman

School of Biological Sciences: Faculty Publications

Background: Sexual selection is largely driven by the availability of mates. Theory predicts that male competition and female choice should be density-dependent, with males competing more intensely at relatively high density, and females becoming increasingly discriminating when there are more males from whom to choose. Evidence for flexible mating decisions is growing, but we do not understand how environmental variation is incorporated into mate sampling strategies. We mimicked threespine stickleback (Gasterosteus aculeatus) breeding conditions in pools with high and low densities of nesting males and allowed females to search for mates to determine whether 1) mate search strategies change with …


Nutritional Physiology Of Life-History Trade-Offs: How Food Protein–Carbohydrate Content Influences Life-History Traits In The Wing-Polymorphic Cricket Gryllus Firmus, Rebecca M. Clark, Anthony J. Zera, Spencer T. Behmer Jan 2015

Nutritional Physiology Of Life-History Trade-Offs: How Food Protein–Carbohydrate Content Influences Life-History Traits In The Wing-Polymorphic Cricket Gryllus Firmus, Rebecca M. Clark, Anthony J. Zera, Spencer T. Behmer

School of Biological Sciences: Faculty Publications

Although life-history trade-offs result from the differential acquisition and allocation of nutritional resources to competing physiological functions, many aspects of this topic remain poorly understood. Wing-polymorphic insects, which possess alternative morphs that trade off allocation to flight capability versus early reproduction, provide a good model system for exploring this topic. In this study, we used the wing-polymorphic cricket Gryllus firmus to test how expression of the flight capability versus reproduction trade-off was modified across a heterogeneous protein–carbohydrate nutritional landscape. Newly molted adult female long- and short-winged crickets were given one of 13 diets with different concentrations and ratios of protein …


Epistasis Constrains Mutational Pathways Of Hemoglobin Adaptation In High-Altitude Pikas, Danielle M. Tufts, Chandrasekhar Natarajan, Inge G. Revsbech, Joana Projecto- Garcia, Federico G. Hoffmann, Roy E. Weber, Angela Fago, Hideaki Moriyama, Jay F. Storz Jan 2015

Epistasis Constrains Mutational Pathways Of Hemoglobin Adaptation In High-Altitude Pikas, Danielle M. Tufts, Chandrasekhar Natarajan, Inge G. Revsbech, Joana Projecto- Garcia, Federico G. Hoffmann, Roy E. Weber, Angela Fago, Hideaki Moriyama, Jay F. Storz

School of Biological Sciences: Faculty Publications

A fundamental question in evolutionary genetics concerns the roles of mutational pleiotropy and epistasis in shaping trajectories of protein evolution. This question can be addressed most directly by using site-directed mutagenesis to explore the mutational landscape of protein function in experimentally defined regions of sequence space. Here, we evaluate how pleiotropic trade-offs and epistatic interactions influence the accessibility of alternative mutational pathways during the adaptive evolution of hemoglobin (Hb) function in high-altitude pikas (Mammalia: Lagomorpha). By combining ancestral protein resurrection with a combinatorial protein-engineering approach, we examined the functional effects of sequential mutational steps in all possible pathways that produced …


Contribution Of A Mutational Hot Spot To Hemoglobin Adaptation In High-Altitude Andean House Wrens, Spencer C. Galen, Chandrasekhar Natarajan, Hideaki Moriyama, Roy E. Weber, Angela Fago, Phred M. Benham, Andrea N. Chavez, Zachary A. Cheviron, Jay F. Storz, Christopher C. Witt Jan 2015

Contribution Of A Mutational Hot Spot To Hemoglobin Adaptation In High-Altitude Andean House Wrens, Spencer C. Galen, Chandrasekhar Natarajan, Hideaki Moriyama, Roy E. Weber, Angela Fago, Phred M. Benham, Andrea N. Chavez, Zachary A. Cheviron, Jay F. Storz, Christopher C. Witt

School of Biological Sciences: Faculty Publications

A key question in evolutionary genetics is why certain mutations or certain types of mutation make disproportionate contributions to adaptive phenotypic evolution. In principle, the preferential fixation of particular mutations could stem directly from variation in the underlying rate of mutation to function-altering alleles. However, the influence of mutation bias on the genetic architecture of phenotypic evolution is difficult to evaluate because data on rates of mutation to function-altering alleles are seldom available. Here, we report the discovery that a single point mutation at a highly mutable site in the βA-globin gene has contributed to an evolutionary change in hemoglobin …


Transcriptional ‘Memory’ Of A Stress: Transient Chromatin And Memory (Epigenetic) Marks At Stress-Response Genes, Zoya Avramova Jan 2015

Transcriptional ‘Memory’ Of A Stress: Transient Chromatin And Memory (Epigenetic) Marks At Stress-Response Genes, Zoya Avramova

School of Biological Sciences: Faculty Publications

Drought, salinity, extreme temperature variations, pathogen and herbivory attacks are recurring environmental stresses experienced by plants throughout their life. To survive repeated stresses, plants provide responses that may be different from their response during the first encounter with the stress. A different response to a similar stress represents the concept of ‘stress memory’. A coordinated reaction at the organismal, cellular and gene/genome levels is thought to increase survival chances by improving the plant’s tolerance/ avoidance abilities. Ultimately, stress memory may provide a mechanism for acclimation and adaptation. At the molecular level, the concept of stress memory indicates that the mechanisms …


Parasitology In An Archaeological Context: Analysis Of Medieval Burials In Nivelles, Belgium, S. E. Rácz, Elisa Pucu De Araujo, E. Jensen, C. Mostek, Johnica J. Morrow, M. L. Van Hove, R. Bianucci, D. Willems, F. Heller, Adauto Araujo, Karl Reinhard Jan 2015

Parasitology In An Archaeological Context: Analysis Of Medieval Burials In Nivelles, Belgium, S. E. Rácz, Elisa Pucu De Araujo, E. Jensen, C. Mostek, Johnica J. Morrow, M. L. Van Hove, R. Bianucci, D. Willems, F. Heller, Adauto Araujo, Karl Reinhard

Karl Reinhard Publications

Coprolites were recovered from three burials near the Grand Place of Nivelles, Belgium. These remains yielded evidence of geohelminth parasitism. The evidence contributes to studies of differential parasite egg preservation related to the taphonomic conditions within the three burials. Using coprolite analysis techniques, parasite egg concentrations were quantified for each burial. Coprolites from the individual in Burial 122 were abnormally large and abundant, indicating an intestinal blockage. Additionally, this individual hosted an extremely high number of parasites evinced by the calculated parasite egg concentrations (Trichuris trichiura = 1,577,679 total eggs; Ascaris lumbricoides = 202,350 total eggs). Statistical analyses revealed …


Paleoparasitology – Human Parasites In Ancient Material, Adauto Araújo, Karl Reinhard, Luiz Fernando Ferreira Jan 2015

Paleoparasitology – Human Parasites In Ancient Material, Adauto Araújo, Karl Reinhard, Luiz Fernando Ferreira

Karl Reinhard Publications

Parasite finds in ancient material launched a new field of science: paleoparasitology. Ever since the pioneering studies, parasites were identified in archaeological and paleontological remains, some preserved for millions of years by fossilization. However, the paleoparasitological record consists mainly of parasites found specifically in human archaeological material, preserved in ancient occupation sites, from prehistory until closer to 2015. The results include some helminth intestinal parasites still commonly found in 2015, such as Ascaris lumbricoides, Trichuris trichiura and hookworms, besides others such as Amoebidae and Giardia intestinalis, as well as viruses, bacteria, fungi and arthropods. These parasites as a …


Electrostatic Charge On Flying Hummingbirds And Its Potential Role In Pollination, Marc Badger, Victor Manuel Ortega-Jimenez, Lisa Von Ribenau, Ashley Smiley, Robert Dudley, Alexei Gruverman , Editor Jan 2015

Electrostatic Charge On Flying Hummingbirds And Its Potential Role In Pollination, Marc Badger, Victor Manuel Ortega-Jimenez, Lisa Von Ribenau, Ashley Smiley, Robert Dudley, Alexei Gruverman , Editor

Alexei Gruverman Publications

Electrostatic phenomena are known to enhance both wind- and insect-mediated pollination, but have not yet been described for nectar-feeding vertebrates. Here we demonstrate that wild Anna's Hummingbirds (Calypte anna) can carry positive charges up to 800 pC while in flight (mean ± s.d.: 66 ± 129 pC). Triboelectric charging obtained by rubbing an isolated hummingbird wing against various plant structures generated charges up to 700 pC. A metal hummingbird model charged to 400 pC induced bending of floral stamens in four plants (Nicotiana, Hemerocallis, Penstemon, and Aloe spp.), and also attracted falling Lycopodium spores at distances of < 2 mm. Electrostatic forces may therefore influence pollen transfer onto nectar-feeding birds.


Wildland Fire Deficit And Surplus In The Western United States, 1984–2012, Sean A. Parks, Carol Miller, Marc-André Parisien, Lisa M. Holsinger, Solomon Z. Dobrowski, John Abatzoglou Jan 2015

Wildland Fire Deficit And Surplus In The Western United States, 1984–2012, Sean A. Parks, Carol Miller, Marc-André Parisien, Lisa M. Holsinger, Solomon Z. Dobrowski, John Abatzoglou

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Wildland fire is an important disturbance agent in the western US and globally. However, the natural role of fire has been disrupted in many regions due to the influence of human activities, which have the potential to either exclude or promote fire, resulting in a ‘‘fire deficit’’ or ‘‘fire surplus’’, respectively. In this study, we developed a model of expected area burned for the western US as a function of climate from 1984 to 2012.We then quantified departures from expected area burned to identify geographic regions with fire deficit or surplus. We developed our model of area burned as a …


Patterns Of Substance Use Initiation Among Indigenous Adolescents, Les B. Whitbeck, Brian E. Armenta Jan 2015

Patterns Of Substance Use Initiation Among Indigenous Adolescents, Les B. Whitbeck, Brian E. Armenta

Department of Sociology: Faculty Publications

Background—The data for this study come from an eight-wave panel study of Indigenous (Canadian First Nations and American Indian) adolescents from three U.S. reservations and four Canadian reserves.

Objectives—Our objective was to investigate variations in patterns of substance use initiation from early adolescence through early adulthood using data collected annually for 8 years.

Method—At baseline the sample included 675 Indigenous adolescents (M age = 11.10, SD = .83; 50.3% girls). First, we calculated cumulative rates of substance use initiation by age. We then examined whether the cumulative initiation rates were moderated by gender using logistic regression …


Widespread Detection Of Antibodies To Leptospira In Feral Swine In The United States, K. K. Pedersen, K. L. Pabilonia, T. D. Anderson, S. N. Bevins, C. R. Hicks, J. M. Kloft, Thomas J. Deliberto Jan 2015

Widespread Detection Of Antibodies To Leptospira In Feral Swine In The United States, K. K. Pedersen, K. L. Pabilonia, T. D. Anderson, S. N. Bevins, C. R. Hicks, J. M. Kloft, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

As feral swine continue to expand their geographical range and distribution across the United States, their involvement in crop damage, livestock predation, and pathogen transmission is likely to increase. Despite the relatively recent discovery of feral swine involvement in the aetiology of a variety of pathogens, their propensity to transmit and carry a wide variety of pathogens is disconcerting. We examined sera from 2055 feral swine for antibody presence to six serovars of Leptospira that can also infect humans, livestock or domestic animals. About 13% of all samples tested positive for at least one serovar, suggesting that Leptospira infection is …


Anticoagulant Rodenticide Exposure And Toxicosis In Coyotes (Canis Latrans) In The Denver Metropolitan Area, Sharon A. Poessel, Stewart W. Breck, Karen A. Fox, Eric M. Gese Jan 2015

Anticoagulant Rodenticide Exposure And Toxicosis In Coyotes (Canis Latrans) In The Denver Metropolitan Area, Sharon A. Poessel, Stewart W. Breck, Karen A. Fox, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Anticoagulant rodenticides are widely used in urban areas to control rodent pests and are responsible for secondary poisoning in many nontarget wildlife species. We tested the livers of five coyotes (Canis latrans) in the Denver Metropolitan Area, Colorado, US, for anticoagulant rodenticides. All five livers were positive for brodifacoum, with values ranging from 95 ppb to 320 ppb, and one liver was positive for bromadiolone, with a value of 885 ppb. Both of these rodenticides are second-generation anticoagulants, which are more potent and more likely to cause secondary poisoning than first-generation anticoagulants due to their accumulation and persistence …


A Behaviorally-Explicit Approach For Delivering Vaccine Baits To Mesopredators To Control Epizootics In Fragmented Landscapes, James C. Beasley, Todd C. Atwood, Michael E. Byrne, Kurt C. Vercauteren, Shylo R. Johnson, Olin E. Rhodes Jr. Jan 2015

A Behaviorally-Explicit Approach For Delivering Vaccine Baits To Mesopredators To Control Epizootics In Fragmented Landscapes, James C. Beasley, Todd C. Atwood, Michael E. Byrne, Kurt C. Vercauteren, Shylo R. Johnson, Olin E. Rhodes Jr.

United States Department of Agriculture Wildlife Services: Staff Publications

Despite the widespread use of aerial baiting to manage epizootics among free-ranging populations, particularly in rabies management, bait acceptance and seroconversion rates often are lower than required to eliminate spread of disease. Our objectives in this study, therefore, were to evaluate the performance of stratified bait distribution models derived from resource selection functions (RSF) on uptake of placebo rabies baits by raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana), as well as the probability of bait uptake as a function of proximity to bait distribution areas in fragmented agricultural ecosystems. Among 478 raccoons and 108 opossums …


Evaluating And Validating Abundance Monitoring Methods In The Absence Of Populations Of Known Size: Review And Application To A Passive Tracking Index, Lee R. Allen, Richard M. Engeman Jan 2015

Evaluating And Validating Abundance Monitoring Methods In The Absence Of Populations Of Known Size: Review And Application To A Passive Tracking Index, Lee R. Allen, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Rarely is it possible to obtain absolute numbers in free-ranging populations and although various direct and indirect methods are used to estimate abundance, few are validated against populations of known size. In this paper, we apply grounding, calibration and verification methods, used to validate mathematical models, to methods of estimating relative abundance. To illustrate how this might be done, we consider and evaluate the widely applied passive tracking index (PTI) methodology. Using published data, we examine the rationality of PTI methodology, how conceptually animal activity and abundance are related and how alternative methods are subject to similar biases or produce …


Is Anthropogenic Cougar Mortality Compensated By Changes In Natural Mortality In Utah? Insight From Long-Term Studies, Michael L. Wolfe, David N. Koons, David C. Stoner, Patricia Terletzky, Eric M. Gese, David M. Choate, Lise M. Aubry Jan 2015

Is Anthropogenic Cougar Mortality Compensated By Changes In Natural Mortality In Utah? Insight From Long-Term Studies, Michael L. Wolfe, David N. Koons, David C. Stoner, Patricia Terletzky, Eric M. Gese, David M. Choate, Lise M. Aubry

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the interplay between exploitation and natural mortality is essential to guiding sustainable conservation of wildlife. Exploitation of carnivores by humans has long been thought to result in compensatory reductions of natural mortality among survivors. If rates of human exploitation exceed natural mortality, however, such actions will ‘add’ to overall mortality and could imperil the sustainability of such actions. We applied competing risk analyses to >/= 16 years of data for heavily harvested and semi-protected cougar populations in Utah to test the additive and compensatory mortality hypotheses, while accounting for parameter uncertainty. We additionally tested for presence of the two …