Open Access. Powered by Scholars. Published by Universities.®

Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

2008

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 211 - 240 of 647

Full-Text Articles in Biology

Contribution Of Cystine-Glutamate Antiporters To The Psychotomimetic Effects Of Phencyclidine, David A. Baker, Aric Madayag, Lars V. Kristiansen, James H. Meador-Woodruff, Vahram Haroutunian, Ilangovan Raju Jun 2008

Contribution Of Cystine-Glutamate Antiporters To The Psychotomimetic Effects Of Phencyclidine, David A. Baker, Aric Madayag, Lars V. Kristiansen, James H. Meador-Woodruff, Vahram Haroutunian, Ilangovan Raju

Biological Sciences Faculty Research and Publications

Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine–glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine–glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect …


Complementary Dna Sequencing And Identification Of Mrnas From Venomous Gland Of Agkistrodon Piscivorus Leucostoma, Ying Jia, Bruno A. Cantu, Elda E. Sánchez, John C. Pérez Jun 2008

Complementary Dna Sequencing And Identification Of Mrnas From Venomous Gland Of Agkistrodon Piscivorus Leucostoma, Ying Jia, Bruno A. Cantu, Elda E. Sánchez, John C. Pérez

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

To advance our knowledge on the snake venom composition and transcripts expressed in venom gland at the molecular level, we constructed a cDNA library from venom gland of Agkistrodon piscivorus leucostoma for the generation of expressed sequence tags (ESTs) database. From the randomly sequenced 2,112 independent clones, we have obtained ESTs for 1,309 (62%) cDNAs which showed significant deduced amino acid sequence similarity (scores > 80) to previously characterized proteins in NCBI database. Ribosomal proteins make up 47 clones (2%) and the remaining 756 (36%) cDNAs represent either unknown identity or show BLASTX sequence identity scores of < 80 with known GenBank accessions. The most highly expressed gene encoding phospholipase A2 (PLA2) accounting for 35% of A. p. leucostoma venom …


Mutational Studies In The Dntp Binding Pocket Of Human Immunodeficiency Virus Type 1 Reverse Transcriptase, Smita Shukla May 2008

Mutational Studies In The Dntp Binding Pocket Of Human Immunodeficiency Virus Type 1 Reverse Transcriptase, Smita Shukla

Theses

It was earlier postulated that Gln 91 of HIV-1 RT stabilizes the side chain of Tyr 183 via hydrogen bonding interaction between 0(H) of Y1 83 and CO of Q91 (Harris et al., BIOCHEMISTRY 37: 9630, 1998). In an attempt to understand the function of Gln 91 in the catalytic mechanism, mutants of this residue (Gln91 - -> Ala and Gln91 - ->Asn) were generated and subjected to an in-depth analysis. The efficiency of reverse transcription of natural U5-PBS HIV-1 RNA template was severely impaired by both conservative and non-conservative substitutions from Gln—>Asn and Gln—> Ala, a result …


An Improved String Composition Method For Sequence Comparison, Guoquing Lu, Shunpu Zhang, Xiang Fang May 2008

An Improved String Composition Method For Sequence Comparison, Guoquing Lu, Shunpu Zhang, Xiang Fang

Biology Faculty Publications

Background: Historically, two categories of computational algorithms (alignment-based and alignment-free) have been applied to sequence comparison–one of the most fundamental issues in bioinformatics. Multiple sequence alignment, although dominantly used by biologists, possesses both fundamental as well as computational limitations. Consequently, alignment-free methods have been explored as important alternatives in estimating sequence similarity. Of the alignment-free methods, the string composition vector (CV) methods, which use the frequencies of nucleotide or amino acid strings to represent sequence information, show promising results in genome sequence comparison of prokaryotes. The existing CV-based methods, however, suffer certain statistical problems, thereby underestimating the amount of evolutionary …


The Cul7 E3 Ubiquitin Ligase Targets Insulin Receptor Substrate 1 For Ubiquitin-Dependent Degradation, Pascal J. Lafontant May 2008

The Cul7 E3 Ubiquitin Ligase Targets Insulin Receptor Substrate 1 For Ubiquitin-Dependent Degradation, Pascal J. Lafontant

Biology Faculty publications

Recent genetic studies have documented a pivotal growth regulatory role played by the Cullin 7 (CUL7) E3 ubiquitin ligase complex containing the Fbw8-substrate-targeting subunit, Skp1, and the ROC1 RING finger protein. In this report, we identified insulin receptor substrate 1 (IRS-1), a critical mediator of the insulin/insulin-like growth factor 1 signaling, as a proteolytic target of the CUL7 E3 ligase in a manner that depends on mammalian target of rapamycin and the p70 S6 kinase activities. Interestingly, while embryonic fibroblasts of Cul7-/- mice were found to accumulate IRS-1 and exhibit increased activation of IRS-1’s downstream Akt and MEK/ERK pathways, these …


The Parallel Worm Tracker: A Platform For Measuring Average Speed And Drug-Induced Paralysis In Nematodes, Daniel Ramot, Brandon E. Johnson, Tommie L. Berry Jr., Lucinda Carnell, Miriam B. Goodman May 2008

The Parallel Worm Tracker: A Platform For Measuring Average Speed And Drug-Induced Paralysis In Nematodes, Daniel Ramot, Brandon E. Johnson, Tommie L. Berry Jr., Lucinda Carnell, Miriam B. Goodman

All Faculty Scholarship for the College of the Sciences

Background

Caenorhabditis elegans locomotion is a simple behavior that has been widely used to dissect genetic components of behavior, synaptic transmission, and muscle function. Many of the paradigms that have been created to study C. elegans locomotion rely on qualitative experimenter observation. Here we report the implementation of an automated tracking system developed to quantify the locomotion of multiple individual worms in parallel.

Methodology/Principal Findings

Our tracking system generates a consistent measurement of locomotion that allows direct comparison of results across experiments and experimenters and provides a standard method to share data between laboratories. The tracker utilizes a video camera …


Grazing And Virus-Induced Mortality Of Microbial Populations Before And During The Onset Of Annual Hypoxia In Lake Erie, Christopher J. Gobler, Timothy W. Davis, Sarah N. Deonarine, Matthew A. Saxton, Peter J. Lavrentyev, Frank J. Jochem May 2008

Grazing And Virus-Induced Mortality Of Microbial Populations Before And During The Onset Of Annual Hypoxia In Lake Erie, Christopher J. Gobler, Timothy W. Davis, Sarah N. Deonarine, Matthew A. Saxton, Peter J. Lavrentyev, Frank J. Jochem

Biology Faculty Research

Lake Erie is the most productive of the North American Great Lakes and experiences annual periods of hypolimnetic hypoxia with unknown consequences for the microbial food web. We established the abundances and mortality rates of microbes in Lake Erie during thermal stratification and determined how they varied with changes in bottom-water dissolved oxygen concentrations. The microbial plankton community (heterotrophic bacteria, Cyanobacteria, eukaryotic phytoplankton, nanozooplankton, microzooplankton) was quantified in surface and bottom waters along with measurements of herbivory and bacterivory rates on eukaryotic and prokaryotic picoplankton and rates of viral lysis of bacteria. High rates of grazing mortality of prokaryotic picoplankton …


Transient Elevation Of Corticosterone Alters Begging Behavior And Growth Of White-Crowned Sparrow Nestlings, Haruka Wada, Creagh W. Breuner May 2008

Transient Elevation Of Corticosterone Alters Begging Behavior And Growth Of White-Crowned Sparrow Nestlings, Haruka Wada, Creagh W. Breuner

Biological Sciences Faculty Publications

Developing animals may face a cost–benefit tradeoff during growth mediated through hormones such as glucocorticoids, as the hormone is essential for development but can have detrimental consequences. To investigate potential tradeoffs caused by brief, moderate elevations of corticosterone in avian young, we artificially elevated the hormone levels in two ways: feeding corticosterone-containing worms and applying corticosterone dermal patches. The former experiment tested the effects of an acute corticosterone elevation (25 min) on begging behavior, whereas the latter explored the effects of artificially elevated corticosterone for 24 to 48 h on growth. Corticosterone altered both begging behavior and growth of white-crowned …


Evidence In The Carotenoid Biosynthetic Pathway For Variation In Evolutionary Rates, Stephanie A. Anderson May 2008

Evidence In The Carotenoid Biosynthetic Pathway For Variation In Evolutionary Rates, Stephanie A. Anderson

Biology Honors Theses

Many cellular reactions occur in linear metabolic pathways where gene products act sequentially to produce needed compounds. The interrelationships between the products of these loci raises the question of whether they evolve in concert or independently. Previous research addressing this question indicated that in the anthocyanin pathway, which produces important secondary metabolites in plants, the genes encoding downstream enzymes show an accelerated rate of evolution when compared to upstream loci. The hypothesized cause of these differences has been attributed to relaxed selective constraint. This pattern and process has not, however, been tested in other systems. The carotenoid biosynthetic pathway, which …


Sticky Gecko Feet: The Role Of Temperature And Humidity, Peter H. Niewiarowski, Stephanie Lopez, Liehui Ge, Emily Hagan, Ali Dhinojwala May 2008

Sticky Gecko Feet: The Role Of Temperature And Humidity, Peter H. Niewiarowski, Stephanie Lopez, Liehui Ge, Emily Hagan, Ali Dhinojwala

Biology Faculty Research

Gecko adhesion is expected to be temperature insensitive over the range of temperatures typically experienced by geckos. Previous work is limited and equivocal on whether this expectation holds. We tested the temperature dependence of adhesion in Tokay and Day geckos and found that clinging ability at 12 degrees C was nearly double the clinging ability at 32 degrees C. However, rather than confirming a simple temperature effect, our data reveal a complex interaction between temperature and humidity that can drive differences in adhesion by as much as two-fold. Our findings have important implications for inferences about the mechanisms underlying the …


The Role Of Mitochondria Atp-Sensitive Potassium Channel In Cardioprotection, Ksenia Andrukhiv Everton May 2008

The Role Of Mitochondria Atp-Sensitive Potassium Channel In Cardioprotection, Ksenia Andrukhiv Everton

Dissertations and Theses

Mitochondrial ATP-sensitive potassium channel (mitoKATP) has been suggested to be the mediator of cardiac preconditioning. All of the diverse pharmacological and physiological agents that open mitoKATP provide protection against ischemia-reperfusion injury. Some investigators have pointed out that some of these mitoKATP channel openers also inhibit succinate dehydrogenase (SDH), complex II of the electron transport chain. Based on this observation they suggest that it is the inhibition of SDH, and not the opening of mitoKATP channel, that mediates the observed cardioprotection. In this study, I examined four chemically distinct and unrelated pharmacological agents, diazoxide, 3-Nitropropionic Acid …


Selfishness As Second-Order Altruism, Omar Tonsi Eldakar, David Sloan Wilson May 2008

Selfishness As Second-Order Altruism, Omar Tonsi Eldakar, David Sloan Wilson

Biology Faculty Articles

Selfishness is seldom considered a group-beneficial strategy. In the typical evolutionary formulation, altruism benefits the group, selfishness undermines altruism, and the purpose of the model is to identify mechanisms, such as kinship or reciprocity, that enable altruism to evolve. Recent models have explored punishment as an important mechanism favoring the evolution of altruism, but punishment can be costly to the punisher, making it a form of second-order altruism. This model identifies a strategy called “selfish punisher” that involves behaving selfishly in first-order interactions and altruistically in second-order interactions by punishing other selfish individuals. Selfish punishers cause selfishness to be a …


The Reproductive Ecology Of Graptemys Geographica In The Central Canal, Kati Keppen Rush May 2008

The Reproductive Ecology Of Graptemys Geographica In The Central Canal, Kati Keppen Rush

Undergraduate Honors Thesis Collection

Life for all organisms involves carefully managing a limited amount of resources. In many cases these resources affect how organisms Jive on a daily basis. In addition to competition from other species, organisms face competition within their own species, populations, and niches. Those individuals that manage their resources effectively will increase their chances of survival, reproduction, and the continuation of their genes in the gene pool. Studies that focus on life history characteristics of organisms aim to understand the mechanisms used by organisms to increase the chances that their genes will remain in thegenepoolpasttheirown Iifetime.Thegoal ofthesemechanisms istoensuresurvival and maximize reproduction. …


Microbial Colonization Of Deep-Sea Hydrothermal Vent Chimneys, Antoine Pagé May 2008

Microbial Colonization Of Deep-Sea Hydrothermal Vent Chimneys, Antoine Pagé

Dissertations and Theses

Deep-sea hydrothermal vent chimneys harbor some of the most extreme environments supporting life on Earth. In the absence of sunlight, the microbial communities that colonize these deposits are based on energy harvested by chemolithoautotrophs exploiting the chemical disequilibria created as hydrothermal fluids mix with seawater. Although controversial, several models consider deep-sea vent chimneys as likely habitats for primitive ecosystems that developed during the Archean.

The goal of this study was to describe spatial and temporal patterns of microbial colonization in deep-sea vent chimneys emitting high temperature (>300°C) fluids. Microbial community composition and structure were evaluated through analyses of 16S …


An Analysis Of Mer1 Function During Meiotic Splicing Regulation In Saccharomyces Cerevisiae, Frederick William Scherrer May 2008

An Analysis Of Mer1 Function During Meiotic Splicing Regulation In Saccharomyces Cerevisiae, Frederick William Scherrer

Dissertations

The transition from mitosis to meiosis in the yeast Saccharomyces cerevisiae requires a significant change to gene expression profiles. Regulation of pre-messenger RNA splicing patterns during meiosis assists in this transition by fine tuning expression of essential meiotic genes. Produced only during meiosis, Mer1p is linked to the splicing of at least three mRNAs: MER2, MER3, and AMA1. Previous evidence suggests that Mer1p activates splicing by directly recruiting snRNPs or stabilizing intermediate splicing complexes formed on pre-mRNA that contains an intronic Mer1p enhancer element. However, some splicing factors, especially accessory/non-snRNP factors, have critical roles in retaining unspliced pre-mRNAs in the …


Spatial And Temporal Variation In The Natal Otolith Chemistry Of A Hawaiian Reef Fish: Prospects For Measuring Population Connectivity, Benjamin I. Ruttenberg, Scott L. Hamilton, Robert R. Warner May 2008

Spatial And Temporal Variation In The Natal Otolith Chemistry Of A Hawaiian Reef Fish: Prospects For Measuring Population Connectivity, Benjamin I. Ruttenberg, Scott L. Hamilton, Robert R. Warner

Biological Sciences

One of the most compelling unanswered questions in marine ecology is the extent to which local populations are connected via larval exchange. Recent work has suggested that variation in the chemistry of otoliths (earstones) of fishes may function as a natural tag, potentially allowing investigators to determine sources of individual larvae and estimate larval connectivity. We analyzed the spatial and temporal variation in natal otolith chemistry of a benthic-spawning reef fish from the Hawaiian Islands. We found no consistent chemical variation at the largest scale (>100 km, among islands), but found significant variation at moderate scales (sites within islands, …


Somatostatin Regulates Raw 264.7 Cell Cytokine Release, Shilpa Swarup May 2008

Somatostatin Regulates Raw 264.7 Cell Cytokine Release, Shilpa Swarup

Seton Hall University Dissertations and Theses (ETDs)

Immigrant monocytes and resident macrophages propagate the vertebrate innate immune response through cell migration and cytokine production. Monocytes responding to inflammatory challenge migrate into tissues, and as resident macrophages, release a major pro-inflammatory cytokine, tumor necrosis factor a (TNF-a). Macrophge cytokine synthesis is known to be under both negative and positive regulatory control. Recent studies have shown that somatostatin (SRIF) regulates monocyte and peritoneal macrophages. However, the effects of SRIF on RAW 264.7 cells, a transformed monocyte/macrophage cell line, have not been investigated. In the present study, SRIF effect on cytokine release in LPS stimulated RAW 264. 7 cells was …


Revisiting A Model Of Ontogenetic Growth: Estimating Model Parameters From Theory And Data, Melanie E. Moses, Chen Hou, William H. Woodruff, Geoffrey B. West, Jeffery C. Nekola, Wenyun Zuo, James H. Brown May 2008

Revisiting A Model Of Ontogenetic Growth: Estimating Model Parameters From Theory And Data, Melanie E. Moses, Chen Hou, William H. Woodruff, Geoffrey B. West, Jeffery C. Nekola, Wenyun Zuo, James H. Brown

Biological Sciences Faculty Research & Creative Works

The ontogenetic growth model (OGM) of West et al. provides a general description of how metabolic energy is allocated between production of new biomass and maintenance of existing biomass during ontogeny. Here, we reexamine the OGM, make some minor modifications and corrections, and further evaluate its ability to account for empirical variation on rates of metabolism and biomass in vertebrates both during ontogeny and across species of varying adult body size. We show that the updated version of the model is internally consistent and is consistent with other predictions of metabolic scaling theory and empirical data. The OGM predicts not …


Analysis Of The Cyc1 Promoter In Candida Albicans, Tomica Blocker May 2008

Analysis Of The Cyc1 Promoter In Candida Albicans, Tomica Blocker

McCabe Thesis Collection

Scientists are considering two factors that may be important in the pathogenesis of C. albicans', it's capability to morph from yeast to hyphal phase, and its differences in colony morphology, cell shape, cell surface and cell permeability. (5) Unfortunately, unlike the bacteria, yeasts do not yet have proven virulence factors. However, science is suggesting that some of the major factors which contribute to the virulence of Candida are its ability to form hyphae, its ability to resist phagocytosis, its ability to adhere to epithelial cell surfaces, its ability to grow well at 37 degrees Celsius, and its ability to secrete …


Short Report: Detection Of Plasmodium Falciparum Histidine-Rich Protein Ii In Saliva Of Malaria Patients, Nana Wilson, Andrew Adjei, Winston Anderson, Stella Baidoo, Jonathan Stiles May 2008

Short Report: Detection Of Plasmodium Falciparum Histidine-Rich Protein Ii In Saliva Of Malaria Patients, Nana Wilson, Andrew Adjei, Winston Anderson, Stella Baidoo, Jonathan Stiles

Department of Biology Faculty Publications

Detection of Plasmodium falciparum parasites in patients with malaria necessitates drawing blood, which increases the risk of accidental infections and is poorly accepted in communities with blood taboos. Thus, non-invasive, cost-effective malaria tests that minimize the need for blood collection are needed. Plasmodium falciparum histidine-rich protein II (PfHRP II) levels in plasma and saliva were compared in malaria-positive and -negative patients in Ghana. Plasma and saliva obtained from 30 thick-film positive and 10 negative children were evaluated for PfHRP II by ELISA. Among the 30 children with positive blood smear, 16 (53%) were PfHRP II positive in plasma and 13 …


A Systematic And Taxonomic Review Of The Family Pseudotanaidae (Crustacea: Peracarida: Tanaidacea) Based Primarily On Morphometry Cladistic Analyses, Jerry Alan Mclelland May 2008

A Systematic And Taxonomic Review Of The Family Pseudotanaidae (Crustacea: Peracarida: Tanaidacea) Based Primarily On Morphometry Cladistic Analyses, Jerry Alan Mclelland

Dissertations

Species of the tanaid family Pseudotanaidae, established by Jurgen Sieg in 1973, have been reported from all the world's oceans in depths ranging from near the surface to below 6,000 m. The family currently consists of 46 characteristically small tanaidomorph species residing in two subfamilies, the Cryptocopinae (seven species) and the Pseudotanainae (39 species). Members of the more ancestral Crytocopinae differ from the Pseudotanainae by having females with four rather than three antennule articles and a complete separation of the maxilliped endites. The primary objective of this study was to test the hypothesis that the current structure of the family …


Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy May 2008

Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy

Biology Faculty Research

Birds in which both sexes produce complex song are more common in the tropics than in the temperate north, where typically only males sing. Yet surprisingly little is known about female song characteristics in most tropical species. Here we present a comparison of female and male singing behaviors in the Streak-backed Oriole (Icterus pustulatus), a tropical songbird in which both sexes perform solo songs. Females sing much more frequently than males and produce songs with similar acoustic complexity. Rates of singing by both sexes were higher during breeding than postbreeding while the rates of most other vocalizations did …


Integrating Across Life-History Stages: Consequences Of Natal Habitat Effects On Dispersal, Michael F. Benard, Shannon J. Mccauley May 2008

Integrating Across Life-History Stages: Consequences Of Natal Habitat Effects On Dispersal, Michael F. Benard, Shannon J. Mccauley

Biological Sciences

Ecological and evolutionary processes are affected by forces acting at both local and regional scales, yet our understanding of how these scales interact has remained limited. These processes are fundamentally linked through individuals that develop as juveniles in one environment and then either remain in the natal habitat or disperse to new environments. Empirical studies in a diverse range of organisms have demonstrated that the conditions experienced in the natal habitat can have profound effects on the adult phenotype. This environmentally induced phenotypic variation can in turn affect the probability that an individual will disperse to a new environment and …


Inhibition Of Barnacle (Amphibalanus Amphitrite) Cyprid Settlement By Means Of Localized, Pulsed Electric Fields, Rodolfo E. Perez-Roa, Marc A. Anderson, Dan Rittschof, Beatriz Orihuela, Dean Wendt, Gregory L. Kowalke, Daniel R. Noguera May 2008

Inhibition Of Barnacle (Amphibalanus Amphitrite) Cyprid Settlement By Means Of Localized, Pulsed Electric Fields, Rodolfo E. Perez-Roa, Marc A. Anderson, Dan Rittschof, Beatriz Orihuela, Dean Wendt, Gregory L. Kowalke, Daniel R. Noguera

Biological Sciences

The increasing needs for environmental friendly antifouling coatings have led to investigation of new alternatives for replacing copper and TBT-based paints. In this study, results are presented from larval settlement assays of the barnacle Amphibalanus (= Balanus) amphitrite on planar, interdigitated electrodes (IDE), having 8 or 25 mum of inter-electrode spacing, upon the application of pulsed electric fields (PEF). Using pulses of 100 ms in duration, 200 Hz in frequency and 10 V in pulse amplitude, barnacle settlement below 5% was observed, while similar IDE surfaces without pulse application had an average of 40% settlement. The spacing between the electrodes …


Heritability Of Longevity In Captive Populations Of Nondomesticated Mammals And Birds, Robert Ricklefs, Carlos Cadena May 2008

Heritability Of Longevity In Captive Populations Of Nondomesticated Mammals And Birds, Robert Ricklefs, Carlos Cadena

Biology Department Faculty Works

We used variance components analysis and offspring–parent regression to estimate the heritability of age at death in zoo populations of several species of mammals and birds. A meta-analysis over 14 species of mammals indicated a variance–component heritability of 0.53. More conservative regression estimates of heritability for the same species averaged 0.17. Offspring–parent regressions were not significant for any of eight species of birds. Heritabilities for data simulated with frailty and age-at-death models showed that sources of variation in age at death cannot be distinguished from observed heritabilities. The CVA in age at death in six mammal species, based on parent–offspring …


The Relationship Of Oribatid Soil Mite Abundance To Abiotic And Biotic Factors, Carolyn Hess May 2008

The Relationship Of Oribatid Soil Mite Abundance To Abiotic And Biotic Factors, Carolyn Hess

Biology Theses - Archive

Oribatid soil mites primarily feed on fungi and dead organisms. They belong to the arthropod subclass, Acari, that are believed to contribute to soil processes such as plant litter breakdown and nutrient release. In order to facilitate more accurate predictions about obscure soil processes, research has been done that has attempted to correlate soil mite abundance and diversity to more easily measured aboveground biota. The present study examined monthly Oribatid soil mite abundance and its relationship to four different plant communities in North Texas: mowed grass monoculture, un-managed field, riparian, and woodland, during one growing season. Due to the nutritional …


Granivores And Restoration: Implications Of Invasion And Considerations Of Context-Dependent Seed Removal, Steven M. Ostoja May 2008

Granivores And Restoration: Implications Of Invasion And Considerations Of Context-Dependent Seed Removal, Steven M. Ostoja

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Granivores are important components of sagebrush communities in western North America. These same regions are being altered by the invasion of the exotic annual Bromus tectorum (cheatgrass) that alters physical and biological dynamics in ways that appear to promote its persistence. This research directly relates to the restoration of B. tectorum-dominated systems in two inter-related ways. First, because these landscapes have large quantities of seeds applied during restoration, it is important to determine the major granivore communities in intact sagebrush communities and in nearby cheatgrass-dominated communities. Second, it is important to develop an understanding of patterns of seed harvest …


An Investigation Of The Early Life-History Of Brown Trout (Salmo Trutta) And Potential Influences On Invasion Success In The Logan River, Utah, Jeremiah Wood May 2008

An Investigation Of The Early Life-History Of Brown Trout (Salmo Trutta) And Potential Influences On Invasion Success In The Logan River, Utah, Jeremiah Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the significant threats posed by nonnative fish species worldwide, it is important to understand how life-history strategies of individual species interact with environmental conditions to explain the success or failure of nonnative fish invasions. Brown trout are prolific invaders, but often exhibit upstream distributional limits in Intermountain West streams, potentially due to a maladaptive reproductive life-history strategy influenced by hydrologic conditions in high-elevation areas. We used redd counts, egg survival experiments, and temperature modeling to investigate the reproductive life-history strategy of brown trout and its potential for success along an elevational stream gradient. We documented brown trout spawning …


Ponderosa Pine Mortality And Bark Beetle-Host Dynamics Following Prescribed And Wildland Fires In The Northern Rocky Mountains, Usa, Ryan Stephen Davis May 2008

Ponderosa Pine Mortality And Bark Beetle-Host Dynamics Following Prescribed And Wildland Fires In The Northern Rocky Mountains, Usa, Ryan Stephen Davis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ponderosa pine delayed mortality, and bark beetle attacks and emergence were monitored on 459 trees for 3 years following one prescribed fire in Idaho and one wildland fire in Montana. Resin flow volume (ml) was measured on 145 fire-injured ponderosa pine 2 and 3 years post-fire. Logistic regression was used to construct two predictive ponderosa pine mortality models, and two predictive bark beetle-attack models. Post-fire delayed tree mortality was greater with the presence of primary bark beetles independent of diameter at breast height (DBH) (cm), and was greater in smaller diameter trees most likely due to direct effects of fire-caused …


Conservation Implications Of Winter-Feeding Policies For Mule Deer In Utah, Chris C. Peterson May 2008

Conservation Implications Of Winter-Feeding Policies For Mule Deer In Utah, Chris C. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Policies regulating wildlife winter-feeding programs may have long-term impacts on conservation and future management of both target and non-target species. In 2000, the Utah Wildlife Board, upon reviewing input from a series of public regional meetings, adopted a Utah Big Game Winter-Feeding Policy. The Utah Division of Wildlife Resources used this policy to regulate winter-feeding programs for mule deer in northern Utah, 2001-2005. I monitored the program effects on mule deer biology, activity and migration, and winter browse utilization and productivity.

While feed rations generally compensated for protein and energy deficiencies, they may overlook mineral deficiencies. To determine if mule …