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2005

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Dispiro-1,2,4-Trioxane Analogues Of A Prototype Dispiro-1,2,4-Trioxolane: Mechanistic Comparators For Artemisinin In The Context Of Reaction Pathways With Iron(Ii), Yuanqing Tang, Yuxiang Dong, Xiaofang Wang, Kamaraj Sriraghavan, James K. Wood, Jonathan L. Vennerstrom May 2005

Dispiro-1,2,4-Trioxane Analogues Of A Prototype Dispiro-1,2,4-Trioxolane: Mechanistic Comparators For Artemisinin In The Context Of Reaction Pathways With Iron(Ii), Yuanqing Tang, Yuxiang Dong, Xiaofang Wang, Kamaraj Sriraghavan, James K. Wood, Jonathan L. Vennerstrom

Chemistry Faculty Publications

Single electron reduction of the 1,2,4-trioxane heterocycle of artemisinin (1) forms primary and secondary carbon-centered radicals. The complex structure of 1 does not lend itself to a satisfactory dissection of the electronic and steric effects that influence the formation and subsequent reaction of these carbon-centered free radicals. To help demarcate these effects, we characterized the reactions of achiral dispiro-1,2,4-trioxolane 4 and dispiro-1,2,4-trioxanes 5−7 with ferrous bromide and 4-oxo-TEMPO. Our results suggest a small preference for attack of Fe(II) on the nonketal peroxide oxygen atom of 1. For 4, but not for 5 and 6 …

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Mixed-Age Groups In After-School And Out-Of-School Time Programs, Marilyn F. Rasmussen May 2005

Mixed-Age Groups In After-School And Out-Of-School Time Programs, Marilyn F. Rasmussen

SDSU Extension Extra Archives

Formal education may have come full circle. Schools have evolved from multi-aged one-room school houses to single-age classrooms, and now some schools are returning to multi-aged classrooms. Educators are revisiting the concept and promise of mixed-age groupings to encourage individual learning and development in a diverse environment.

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The Effect Of Wildfire On Populations Of The Jemez Mountains Salamander (Plethodon Neomexicanus) With Consideration To Arthropod Prey Availability Following The Cerro Grande Fire Of Northern New Mexico, Michelle R. Cummer May 2005

The Effect Of Wildfire On Populations Of The Jemez Mountains Salamander (Plethodon Neomexicanus) With Consideration To Arthropod Prey Availability Following The Cerro Grande Fire Of Northern New Mexico, Michelle R. Cummer

Biology

Fire regimes in North America, including the American Southwest, have undergone relatively dramatic shifts in the last century, resulting in novel stand-replacing fires that are changing landscapes in unprecedented ways. Some possible effects of these novel landscape changes on a terrestrial plethodontid salamander (Plethodon neomexicanus) were investigated. Microhabitat temperatures in four burn-severity types following recent fires were measured. Temperatures were significantly greater in high-severity and moderate-severity burn areas than in low-severity and unburned areas. Salamander presence/absence data from four burn-severity types that were documented as having salamanders prior to wildfire are considered. The proportions of presence and absence …

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Physiological And Molecular Genetic Mechanisms Of Tetrodotoxin Resistance In The Garter Snake, Thamnophis Sirtalis, Shana L. Geffeney May 2005

Physiological And Molecular Genetic Mechanisms Of Tetrodotoxin Resistance In The Garter Snake, Thamnophis Sirtalis, Shana L. Geffeney

Biology

The focus of this project was the identification of physiological and molecular genetic mechanisms of tetrodotoxin resistance in the common garter snake, Thamnophis sirtalis. Tetrodotoxin, a neurotoxin, specifically blocks the activity of voltage-gated sodium channels. Some populations of garter snake have evolved geographically variable resistance to tetrodotoxin in a coevolutionary arms race with their tetrodotoxic prey, newts of the genus Taricha. Variation in tetrodotoxin resistance among snake populations is extreme and spans three orders of magnitude. Here I describe a physiological mechanism of whole-animal tetrodotoxin resistance in four populations of snake that represent two independent evolutionary origins of …

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Ecology And Physiology Of Tetrodotoxin Toxicity In The Newt Genus Taricha: Ramifications For A Coevolutionary Predator-Prey Interaction, Charles T. Hanifin May 2005

Ecology And Physiology Of Tetrodotoxin Toxicity In The Newt Genus Taricha: Ramifications For A Coevolutionary Predator-Prey Interaction, Charles T. Hanifin

Biology

I examined the ecology and physiology of tetrodotoxin (TTX) toxicity in the newt genus Taricha (family Salamandridae) to understand the forces that have shaped the adaptive evolution of TTX toxicity in this group. In particular, this work sought to explore how coevolution with a TTX-resistant predator (the garter snake, Thamnophis sirtalis) has shaped patterns of phenotypic diversity in TTX toxicity among populations of Taricha. I developed a set of techniques to directly measure levels of TTX in the skin of newts, and used those measurements to estimate the amount of TTX a snake predator would be exposed to …

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A Qualitative And Quantitative Characterization Of Emergent, Distributed Computation As A Possible Mechanism For Biological Information Processing In Stomatal Networks, Susanna M. Messinger May 2005

A Qualitative And Quantitative Characterization Of Emergent, Distributed Computation As A Possible Mechanism For Biological Information Processing In Stomatal Networks, Susanna M. Messinger

Biology

This research presents an exploration of the qualitative and quantitative properties of emergent, distributed computation in artificial cellular networks with the goal of better understanding the same computational mechanism as it might occur in biological systems, particularly plants. Stomata are tiny pores on the surface of a plant. As the sole pathway for the exchange of gasses between a plant and the atmosphere, stomata are responsible for both CO2 assimilation and water loss. By adjusting their pore size in response to environmental conditions, stomata appear to maximize carbon assimilation while minimizing water loss—a constrained optimization problem. Stomata interact with …

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Responses Of Stream-Breeding Amphibians To Riparian Buffers In Headwater Streams: Ameliorating The Effects Of Regeneration Harvest, Kathleen Louise Pollett May 2005

Responses Of Stream-Breeding Amphibians To Riparian Buffers In Headwater Streams: Ameliorating The Effects Of Regeneration Harvest, Kathleen Louise Pollett

Biology

This study focused on steep (>10 °) headwater streams in a volcanic geologic region in southwestern Washington. The presence and abundance of Rhyacotriton cascadae, Ascaphus truei, and Dicamptodon spp. (D. copei and D. tenebrosus) were assessed in four treatment types (unbuffered (clearcuts), buffered (12 to 23 m wide), second-growth (35 to 50 years old stands), and unmanaged (not previously logged)). No difference among treatments for R. cascadae or Dicamptodon spp. presence was found. R. cascadae abundance did not differ statistically between buffered and second-growth streams or between buffered and unbuffered streams. R. cascadae densities did …

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Functional Diversity In Autotrophic Ammonia-Oxidizing Bacteria From Agricultural Soils, Teresa E. Koper May 2005

Functional Diversity In Autotrophic Ammonia-Oxidizing Bacteria From Agricultural Soils, Teresa E. Koper

Biology

Ammonia-oxidizing bacteria carry out the first step of nitrification, producing nitrite that is subsequently converted to nitrate, which may contribute to environmental pollution. The objective of this study was to gain insight into the functional diversity of ammonia-oxidizing bacteria in agricultural soils. We investigated the urease encoding gene sequences of several nitrifying bacteria and the kinetics of nitrification of soils treated with different nitrogen sources. Many, but not all, ammonia-oxidizing bacteria produce urease and are capable of hydrolyzing urea for their source of ammonium. The urease operons were sequenced from the betaproteobacterial Nitrosospira sp. NpAV and the gammaproteobacterial Nitrosococcus oceani. …

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Biotic And Abiotic Determinants Of Species Distribution: Desert Horned Lizards (Phrynosoma Platyrhinos) And Ants In A Shrub-Steppe Ecosystem, T. A. Scott Newbold May 2005

Biotic And Abiotic Determinants Of Species Distribution: Desert Horned Lizards (Phrynosoma Platyrhinos) And Ants In A Shrub-Steppe Ecosystem, T. A. Scott Newbold

Biology

The primary objective of this study was to attempt to disentangle the relative importance of biotic vs. abiotic factors on the distribution and abundance of desert horned lizards (Phrynosoma platyrhinos). Research was conducted along a Great Basin shrub-steppe bajada that examined interactions among P. platyrhinos, ants, plants, and soil characteristics. Studies focused on: (1) pattern description and habitat associations of P. platyrhinos, and (2) evaluating specific biotic and abiotic pathways underlying observed patterns of lizard abundance and distribution. Examination of lizard habitat associations along the elevational gradient revealed that unvegetated spaces and cryptobiotic crust cover were …

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Children’S Aid Society Of Halton: A School-Based Model Of Child Welfare Service Delivery, Gary Cameron, Lirondel Hazineh, Karen Frensch May 2005

Children’S Aid Society Of Halton: A School-Based Model Of Child Welfare Service Delivery, Gary Cameron, Lirondel Hazineh, Karen Frensch

Partnerships for Children and Families Project

No abstract provided.

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Family & Children’S Services Of Guelph And Wellington County: A Community-Based Model Of Child Welfare Service Delivery (Full Report), Lirondel Hazineh, Gary Cameron, Karen Frensch May 2005

Family & Children’S Services Of Guelph And Wellington County: A Community-Based Model Of Child Welfare Service Delivery (Full Report), Lirondel Hazineh, Gary Cameron, Karen Frensch

Partnerships for Children and Families Project

No abstract provided.

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Stopover Ecology Of Autumn Landbird Migrants In The Boise Foothills Of Southwestern Idaho, Jay D. Carlisle, Gregory S. Kaltenecker, David L. Swanson May 2005

Stopover Ecology Of Autumn Landbird Migrants In The Boise Foothills Of Southwestern Idaho, Jay D. Carlisle, Gregory S. Kaltenecker, David L. Swanson

Intermountain Bird Observatory Publications and Presentations

The topography of western North America provides a complex landscape for landbird migrants, and stopover patterns in this region are poorly understood. We examined seven years of stopover data (1997–2003) from a montane area in southwestern Idaho to determine whether this area provides suitable stopover habitat. We compared the proportion of birds recaptured, stopover duration, and changes in energetic condition within and among species and between two mist-netting sites located in different habitats. The proportion of birds recaptured ranged from zero to over 20%, and fewer than 5% of individuals were recaptured in most species. Mean minimum stopover durations from …

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Stim1, An Essential And Conserved Component Of Store-Operated Ca2+ Channel Function, Jack Roos, Paul J. Digregorio, Andriy V. Yeromin, Kari Ohlsen, Maria I. Lioudyno, Shenyuan L. Zhang, Olga Safrina, J. Ashot Kozak, Steven L. Wagner, Michael D. Cahalan, Gönül Veliçelebi, Kenneth A. Stauderman May 2005

Stim1, An Essential And Conserved Component Of Store-Operated Ca2+ Channel Function, Jack Roos, Paul J. Digregorio, Andriy V. Yeromin, Kari Ohlsen, Maria I. Lioudyno, Shenyuan L. Zhang, Olga Safrina, J. Ashot Kozak, Steven L. Wagner, Michael D. Cahalan, Gönül Veliçelebi, Kenneth A. Stauderman

Neuroscience, Cell Biology & Physiology Faculty Publications

Store-operated Ca2+ (SOC) channels regulate many cellular processes, but the underlying molecular components are not well defined. Using an RNA interference (RNAi)-based screen to identify genes that alter thapsigargin (TG)-dependent Ca2+ entry, we discovered a required and conserved role of Stim in SOC influx. RNAi-mediated knockdown of Stim in Drosophila S2 cells significantly reduced TG-dependent Ca2+ entry. Patch-clamp recording revealed nearly complete suppression of the Drosophila Ca2+ release-activated Ca2+(CRAC) current that has biophysical characteristics similar to CRAC current in human T cells. Similarly, knockdown of the human homologue STIM1 significantly reduced CRAC channel activity …

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Evolutionary History Of The Clitellariinae And Stratiomyidae (Insecta: Diptera) Using Molecular, Morphological, And Total Evidence Approaches, Colin A. Brammer May 2005

Evolutionary History Of The Clitellariinae And Stratiomyidae (Insecta: Diptera) Using Molecular, Morphological, And Total Evidence Approaches, Colin A. Brammer

Biology

Stratiomyidae is a diverse, cosmopolitan family of Diptera (true flies). One of its twelve subfamilies, Clitellariinae, is distributed in all major biogeographic regions except Antarctica. Understanding the evolutionary history of Clitellariinae is key to reconstructing the phylogeny of Stratiomyidae as a whole because Clitellariinae is united only by shared ancestral characters, and, thus, may not be a natural group. This research investigates the relationships between the genera currently placed within Clitellariinae and the subfamilial relationships of Stratiomyidae using morphology, molecules, and combined data. Morphology was analyzed with the method of parsimony using 97 adult characters. Molecular analyses were performed with …

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Contents, Coalition For Education In The Outdoors May 2005

Contents, Coalition For Education In The Outdoors

Taproot: A Journal of Outdoor Education

The Coalition for Education in the Outdoors is a non-profit network of outdoor and environmental education centers, nature centers, conservation and recreation organizations, outdoor education and experiential education associations, institutions of higher learning, public and private schools, fish and wildlife agencies, and businesses that share a mission the support and furtherance of outdoor education and its goals.

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The Obligation To Endure Again, Sandra Steingraber May 2005

The Obligation To Endure Again, Sandra Steingraber

Taproot: A Journal of Outdoor Education

The author of this letter was a young biologist named Rachel Carson. Carson could not have known, when she penned it, how profound an impact her short letter would have. The Associated Press picked it up for syndication. The Reader's Digest reprinted it. And so her missive found its way onto front porches and breakfast tables, into living rooms and libraries and doctors' office waiting rooms across the nation. At the height of the Cold War, in the midst of an anti-Communist inquisition that had convulsed the federal government, Carson's assertion that "the real wealth of the Nat ion lies …

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The Communication Studies Researcher And The Communication Studies Indexes, David C. Tyler, Signe Swanson, Susan M. Leach May 2005

The Communication Studies Researcher And The Communication Studies Indexes, David C. Tyler, Signe Swanson, Susan M. Leach

University of Nebraska-Lincoln Libraries: Faculty Publications

The existence of widely available large, multi-subject, online databases calls into question the necessity for small, discipline-specific indexes to support research. This study attempts to determine whether the online Communication Studies indexes provide access to the journal literature that researchers in the field actually cite and whether, where the current journal literature is concerned, that access is in any way superior to that provided by large, multi-subject, online indexes.

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Kickshaws, Dave Morice May 2005

Kickshaws, Dave Morice

Word Ways

A collection of linguistic kickshaws.

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When Scoundrels Rule: Review Of The Last Refuge: Patriotism, Politics, And The Environment In An Age Of Terror, By David W. Orr, Robert Costanza May 2005

When Scoundrels Rule: Review Of The Last Refuge: Patriotism, Politics, And The Environment In An Age Of Terror, By David W. Orr, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Book Review of The Last Refuge: Patriotism, Politics, and the Environment in an Age of Terror. David W. Orr. Island Press, Washington, DC, 2004.

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From The Editor, Charles Yaple May 2005

From The Editor, Charles Yaple

Taproot: A Journal of Outdoor Education

Using ecopsychology as a theme, this issue of Taproot rightfully begins with a salute to Michael Cohen. Janet Thomas provides readers with a well-written overview of Michael's life and work in On All Nine Legs - Teaching Outdoor Love to an Indoor World. Like Cohen, Jeannette Armstrong sees a form of insanity that grips modern cultures-a sickness that can only be cured by reconnecting with the natural world that nurtures us. As a Native American (Okanagan), Armstrong provides an outsiders view of the "wild and insane" lifestyles lived by humans in a consumer- oriented world. In Keepers of the Earth, …

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Deconstructing The “War Of All Against All”: The Prevalence And Implications Of War Metaphors And Other Adversarial News Schema In Time, Newsweek, And Maclean’S, Michael Karlberg, Leslie Buell May 2005

Deconstructing The “War Of All Against All”: The Prevalence And Implications Of War Metaphors And Other Adversarial News Schema In Time, Newsweek, And Maclean’S, Michael Karlberg, Leslie Buell

Peace and Conflict Studies

This study examines and critiques the discursive construction of a Hobbesian “war of all against all” in North American commercial news magazines. The prevalence of war metaphors and related adversarial news schemas is documented over a twenty year period, from 1981 to 2000, through an analysis of TIME and Newsweek, along with their Canadian counterpart Maclean’s. After documenting the pervasiveness of these discursive constructs, the paper discusses the underlying causes and potential consequences of these patterns in commercial news discourse. The paper concludes by asserting that this discursively constructed “war of all against all” is highly problematic and unsustainable in …

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Impact Of Tourism On Bird Diversity, Abundance, And Community Composition, May 2005, Micah Scholer May 2005

Impact Of Tourism On Bird Diversity, Abundance, And Community Composition, May 2005, Micah Scholer

Monteverde Institute: Tropical Ecology and Conservation

In recent years the ecotourism industry has been touted as offering incentives for protecting biodiversity while promoting economic growth for the surrounding communities. This paper examines the impact that ecotourism has on bird communities in the Monteverde Cloud Forest Preserve. Abundance and species richness for birds were compared on tourist trails and trails closed to tourist. The results indicated no significant difference in H’ values between trail types. The average species richness between trail types was not significantly different, but tourist trails significantly increased in average abundance. Increases may be a result of food resources provided by the Preserve on …

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"When The President Says 'Democracy'": Examining The Relationship Between Presidential Discourse And Democritizatsiia In Kazakhstan, Elena Pak May 2005

"When The President Says 'Democracy'": Examining The Relationship Between Presidential Discourse And Democritizatsiia In Kazakhstan, Elena Pak

Masters Theses & Specialist Projects

Many expected that the fall of Soviet communism would result in the democratization of its successor states. The majority of the post-Soviet republics announced democracy as their new way of development; however, very few have evolved into democratization processes. Kazakhstan's democratization has resulted in the formation of authoritative presidentialism, though with limited liberalization (Cummings, 2002, p. 9). Kazakhstan has neither established the anomalous democracy as its most influential neighbor in Eastern Europe, Russia, nor has become the extreme sultanism like its Central Asian fellow, Turkmenistan. According to Cummings (2002), Kazakhstan has shaped "a hybrid, transitional regime of part-authoritarianism" (p. 5). …

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Concurrent Validity Of The Clinical Assessment Of Depression With The Beck Depression Inventory-Second Edition, Shelley Hicks May 2005

Concurrent Validity Of The Clinical Assessment Of Depression With The Beck Depression Inventory-Second Edition, Shelley Hicks

Masters Theses & Specialist Projects

Depression is a disorder that can affect every aspect of one's life, ranging from physical health issues to interpersonal relationship difficulties. Therefore, it is imperative that the depressive symptoms of college students be identified, evaluated, and treated. Self-report measures are a common technique to identify depressive symptomatology in individuals and assist in diagnosis and treatment. Existing measures are often used as a criterion by which to validate the psychometric properties and effectiveness of newly designed, self-report measures. The purpose of this investigation was to explore the concurrent validity of a newly published self-report measure of depression, the Clinical Assessment of …

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Exposure Assessment Of Mercury In Fish From Kentucky Surface Waters, Najla Gubari May 2005

Exposure Assessment Of Mercury In Fish From Kentucky Surface Waters, Najla Gubari

Masters Theses & Specialist Projects

Consumption of fish contaminated with mercury is the primary exposure pathway by which humans are exposed to mercury. Mercury is known to be a neurological toxin that can cause attention and language deficits, impaired memory, and impaired visual and motor function, especially in children under the age of six. In addition, mercury exposure can lead to other health problems in adults, such as damage to the kidney and increased risk of coronary heart disease. This study assesses the exposure to mercury through consumption of fish from Kentucky surface waters. The exposure assessment is based on data collected by the Kentucky …

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Melting Beeswax Bodies: The Queen Bee, The Hive, And Identity In Women's Writing, Leigh Johnson May 2005

Melting Beeswax Bodies: The Queen Bee, The Hive, And Identity In Women's Writing, Leigh Johnson

Masters Theses & Specialist Projects

The works examined are poetry by Emily Dickinson, Sylvia Plath, and Audre Lorede, novels by Starhawk, The Fifth Sacred Thing, and Sue Monk Kidd, The Secret Life of Bees, and a drama by Elizabeth Bussey Fentress, The Honey Harvest. In looking at how the women writers construct identity using bee imagery, I propose that they actually subvert the societal devaluation of women. The beeswax bodies represent gendered constructions of how women should behave. The characters "melt" these bodies by refusing to fit the mold and by redesigning the mold to fit themselves.

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Comparison Of The Faces And Numeric Pain Scales For Use In Long-Term Ventilator Patients With Chronic Pain, Diana Miller-Harvey May 2005

Comparison Of The Faces And Numeric Pain Scales For Use In Long-Term Ventilator Patients With Chronic Pain, Diana Miller-Harvey

Graduate Research Projects

Chronic pain is a major cause of illness, disability, and is poorly understood and undertreated by health care professionals. Numerous misconceptions regarding chronic pain in older individuals has led certain health care agencies to require the use of pain scales for pain evaluation in all health care patients. yet, there is research lacking as to which pain scales are appropriate for use with chronic pain, ventilator-dependent, older individuals. The Wong-Baker Faces Scale and Numeric Pain Scale was administered to a convenience sample of male/female patients in a Southeastern, 44-bed, long-term care ventilator hospital. The purpose of this study was to …

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An East-West Comparison Of Migration In North American Wood Warblers, Jeffrey F. Kelly, Richard L. Hutto May 2005

An East-West Comparison Of Migration In North American Wood Warblers, Jeffrey F. Kelly, Richard L. Hutto

Biological Sciences Faculty Publications

That western and eastern songbird migration routes are distinct ecological systems has been proposed for over 100 years. Nonetheless, this distinction has not been widely recognized nor have there been any comparative studies that quantitatively evaluate the differences and similarities between western and eastern songbird migration systems. We drew from previously published research on wood warblers to highlight patterns in stopover ecology that suggest fundamental differences between western and eastern migrants. In particular, we compared biogeography, evolutionary relationships, and stopover ecology of wood warblers from western and eastern North America and found: (1) multiple lines of evidence that indicate western …

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Geography Of Spring Landbird Migration Through Riparian Habitats In Southwestern North America, Susan K. Skagen, Jeffrey F. Kelly, Charles Van Riper Iii, Richard L. Hutto, Deborah M. Finch, David J. Krueper, Cynthia P. Melcher May 2005

Geography Of Spring Landbird Migration Through Riparian Habitats In Southwestern North America, Susan K. Skagen, Jeffrey F. Kelly, Charles Van Riper Iii, Richard L. Hutto, Deborah M. Finch, David J. Krueper, Cynthia P. Melcher

Biological Sciences Faculty Publications

Migration stopover resources, particularly riparian habitats, are critically important to landbirds migrating across the arid southwestern region of North America. To explore the effects of species biogeography and habitat affinity on spring migration patterns, we synthesized existing bird abundance and capture data collected in riparian habitats of the borderlands region of the U.S. and Mexico. We determined the importance of geographic factors (longitude and latitude) in explaining variation in abundances and capture rates of 32 long-distance and three short-distance migrant species. Abundances and capture rates of 13 and 11 species, respectively, increased with increasing longitude, and four species' abundance and …

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Effects Of A Small Mammalian Herbivore On A Grassland Undergoing Restoration, Margaret Murphy May 2005

Effects Of A Small Mammalian Herbivore On A Grassland Undergoing Restoration, Margaret Murphy

Masters Theses & Specialist Projects

This thesis examines the effects of the prairie vole, Microtus ochrogaster, on a grassland undergoing restoration. The study addresses these effects with respect to treatment plots (vole-enhanced enclosures and vole-excluded exclosures) and control plots, which have not had the small mammal community manipulated. This study has also been accepted as a manuscript for publication in the "Proceedings of the 18th North American Prairie Conference."1 Two ancillary studies were also conducted. The first, reported in Appendix I, examines the composition and effects on plant community structure by the unmanipulated, small mammal community from the control plots within the area undergoing restoration …

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