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2010

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Atp-Dependent Chromatin Remodeling Complexes In Xenopus Development, Elvin E. Brown Apr 2010

Atp-Dependent Chromatin Remodeling Complexes In Xenopus Development, Elvin E. Brown

Chemistry and Biochemistry

A central question in the study of vertebrate development is how to account for the exquisite interplay of genes within differentiating cells and of groups of cells as they create the organs of the vertebrate embryo. Recently it has become clear that gene regulation by epigenetic processes adds a formerly unappreciated level of complexity to the regulatory network of development. One form of epigenetic gene regulation is embodied in ATP-dependent chromatin remodeling complexes, which use the energy of ATP hydrolysis to alter the interactions of DNA and histones. Chromatin remodeling complexes can both promote and repress expression of a gene …

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Controls On Antimony And Arsenic Speciation Via Sorption And Redox Chemistry At The Clay Mineral - Water Interface In Natural And Laboratory Settings, Anastasia Gennadyevna Ilgen Apr 2010

Controls On Antimony And Arsenic Speciation Via Sorption And Redox Chemistry At The Clay Mineral - Water Interface In Natural And Laboratory Settings, Anastasia Gennadyevna Ilgen

Chemistry and Biochemistry

Adsorption and redox transformations of contaminants in soil and aqueous environments are often controlled by the available mineral substrates. Aluminosilicates and aluminum oxides are ubiquitous and can influence the speciation and, therefore, the transport and bio-availability of toxic elements such as arsenic (As) and antimony (Sb). It is important to understand the partitioning and redox reactions promoted by these substrates in order to understand and model the transport of As and Sb in soils and surface waters. This study provides a detailed investigation of the sorption and redox behavior of As and Sb in clay-rich natural and laboratory systems. Since …

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Protective Factors Promoting Psychosocial Resilience In Biracial Youths, Gail K. Kawakami-Schwarber Apr 2010

Protective Factors Promoting Psychosocial Resilience In Biracial Youths, Gail K. Kawakami-Schwarber

Counseling

Resilience in adolescents is the achievement of positive outcomes and the attainment of developmental tasks in the face of significant risk. This study identified protective factors promoting resilience in the development of positive self-identity in biracial youths. The rapidly rising biracial youth population is a vulnerable group facing potentially higher risks for mental health and behavioral issues compared to their monoracial counterparts. Identity development, a central psychosocial task of adolescence, is a complex task for biracial youths since they must integrate two ethnic identities. For biracial youths, mastery of the psychosocial identity developmental task can be daunting as they face …

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Climate Change - Implications For Geotourism And Biodiversity Conservation In The Caves Of Southwest Western Australia, Stefan Eberhard Apr 2010

Climate Change - Implications For Geotourism And Biodiversity Conservation In The Caves Of Southwest Western Australia, Stefan Eberhard

KIP Abstracts

Based on a study of caves in southwest Western Australia, this presentation explores the form-process linkages between geology, hydrology and ecology (eco-hydrogeology), and their relationships with climate. This case study demonstrated the impacts and ongoing threat that climate change poses to geo-processes and biodiversity, which has implications for geo/ecotourism globally. Cave geotourism has been practised in southwest Western Australia for more than 100 years. One of the major attractions for visitors to these caves is their spectacular underground lakes and streams. The cave lakes and streams also harbor a rich biodiversity of endemic cave dwelling fauna. Because of a drying …

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Farm Report On Research And Operations 2009, N/A N/A Apr 2010

Farm Report On Research And Operations 2009, N/A N/A

Miscellaneous Publications

No abstract provided.

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Maybe An Answer Is In There: Life Story In Dialogue, Jennifer L. Carroll Apr 2010

Maybe An Answer Is In There: Life Story In Dialogue, Jennifer L. Carroll

Anthropology

This dissertation explores the ways in which Gwich'in women's lives have changed over the past century through the life story and historical and cultural reflections of Vera Englishoe, a Neets'qii Gwich'in woman in her late 50s from Venetie and Fort Yukon. Vera's story illustrates one woman's pathway through changing times and provides an example of resilience in the face of family and community turmoil. This work also shows how Vera uses stories to sustain herself and others amid dialogues that challenge Gwich'in identity and how the Gwich'in approach to knowledge, understanding, and stories emphasize personal experience and accountability, promotes independent …

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Come On Ugzruk, Let Me Win: Experience, Relationality, And Knowing In Kigiqtaamiut Hunting And Ethnography, Josh Wisniewski Apr 2010

Come On Ugzruk, Let Me Win: Experience, Relationality, And Knowing In Kigiqtaamiut Hunting And Ethnography, Josh Wisniewski

Anthropology

This ethnography of marine mammal hunting explores linkages between personal experiences and shared understandings of ecological phenomena among a group of Kigiqtaamiut hunters in Shishmaref, Alaska. Specifically it examines the relationships between Kigiqtaamiut hunters' experiences in the world and means by which the experienced world is brought into being through hunters' ways knowing. This work is informed by three spring hunting seasons spent as a member of a familial marine mammal hunting crew and over 20 months of fieldwork. It addresses hunters' ways of learning, knowing and directly experiencing the reality of the phenomenal world. Exploring a multiplicity of modes …

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Skin Drums, Squeeze Boxes, Fiddles And Phonographs: Musical Interaction In The Western Arctic, Late 18th Through Early 20th Centuries, Paul R. Krejci Apr 2010

Skin Drums, Squeeze Boxes, Fiddles And Phonographs: Musical Interaction In The Western Arctic, Late 18th Through Early 20th Centuries, Paul R. Krejci

Anthropology

This dissertation explores the nature of early globalization in the Western Arctic with a focus on musical interaction between indigenous and foreign populations during the late 18th through the 20 th centuries. The region experienced an unprecedented amount of cultural contact represented by various cultural groups including Native Alaskan, Canadian, Chukotkan, European American, African American, Latin American, Asian American, Oceanic peoples and others. Numbering in the thousands, natives and non-natives developed continuous and long-term relations working as explorers, whalers, traders, missionaries, miners, hunters, trappers, seamstresses, educators, law enforcement officials, and scientists. The Western Arctic's ethnically diverse population, relatively harsh physical …

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Survey Of Bombus Species (Hymenoptera: Apidae) Near Agricultural Lands In Interior Alaska, Rehanon Pampell Apr 2010

Survey Of Bombus Species (Hymenoptera: Apidae) Near Agricultural Lands In Interior Alaska, Rehanon Pampell

Agriculture and Horticulture

Major world pollinators include bees, beetles, flies, butterflies, birds and bats, all of which help pollinate over 75% of Earth's flowering plant species and nearly 75% of the crops. In arctic and subarctic regions, bumble bees are considered important pollinators; however, immediate concerns involving climate change, colony collapse disorders in honey bees, and lack of faunistic insect studies in Alaska emphasize the need to study bumble bees in interior Alaska. I identified seventeen species of bumble bees from three localities: Delta Junction, Fairbanks, and Palmer, Alaska. Not all species were recovered from all localities and species richness and relative abundance …

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Aurora Vol. 03 No. 1 (Fall 2010), N/A N/A Apr 2010

Aurora Vol. 03 No. 1 (Fall 2010), N/A N/A

Aurora

No abstract provided.

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Ways To Help And Ways To Hinder: Climate, Health, And Food Security In Alaska, Philip A. Loring Apr 2010

Ways To Help And Ways To Hinder: Climate, Health, And Food Security In Alaska, Philip A. Loring

Indigenous Studies

This dissertation explores various ecological, socioeconomic, sociopolitical, and biophysical dimensions food security in Alaska. The context for this work is dramatic climatic change and ongoing demographic, socioeconomic and cultural transitions in Alaska's rural and urban communities. The unifying focus of the papers included here are human health. I provide multiple perspectives on how human health relates to community and ecosystem health, and of the roles of managers, policy makers, and researchers can play in supporting positive health outcomes. Topics include methylmercury (MeHg) contamination of wild fish, the impacts of changes to Alaskan landscapes and seascapes on subsistence and commercial activities, …

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Science Education In Rural America: Adaptations For The Ivory Tower, Gregory S. Van Doren Apr 2010

Science Education In Rural America: Adaptations For The Ivory Tower, Gregory S. Van Doren

Indigenous Studies

This thesis illustrated what can happen when academic culture disconnects from the cultures surrounding it. It showed that formal school environments are not always the best places to learn. A discussion of the debate between coherence and fragmentation learning theories illustrated academic chasms and a mindset that science education must originate from within ivory towers to be valued. Rationales for place-based science education were developed. Two National Science Foundation initiatives were compared and contrasted for relevance to Native Science education (a) Informal Science Education and (b) Science Education for New Civic Engagement and Responsibilities. A National Science Foundation instrument, known …

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Neural Network Approach To Classification Of Infrasound Signals, Dong-Chang Lee Apr 2010

Neural Network Approach To Classification Of Infrasound Signals, Dong-Chang Lee

Physics

As part of the International Monitoring Systems of the Preparatory Commissions for the Comprehensive Nuclear Test-Ban Treaty Organization, the Infrasound Group at the University of Alaska Fairbanks maintains and operates two infrasound stations to monitor global nuclear activity. In addition, the group specializes in detecting and classifying the man-made and naturally produced signals recorded at both stations by computing various characterization parameters (e.g. mean of the cross correlation maxima, trace velocity, direction of arrival, and planarity values) using the in-house developed weighted least-squares algorithm. Classifying commonly observed low-frequency (0.015--0.1 Hz) signals at out stations, namely mountain associated waves and high …

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Agroborealis, Vol. 41, Number 1 (2010), School Of Natural Resources And Agricultural Sciences Apr 2010

Agroborealis, Vol. 41, Number 1 (2010), School Of Natural Resources And Agricultural Sciences

Agroborealis

[Geography] -- AMSA: the future of arctic marine shipping: With more shipping traffic in the north and greater marine access due to the retreat of Arctic sea ice, the Arctic states needed to develop a strategy to protect the maritime Arctic, its people, and the environment -- [Forest Sciences] -- Changing the forest and the trees - Is it climate?: Sunspots, sun cycles, El Ninos, La Ninas, atmospheric oscillations, greenhouse gases: climate change has begun to affect the boreal more than any other forest region. / Glenn Patrick Juday -- One Tree in the Tanana Valley: Take one entire tree, …

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Alaskan Physicians' Knowledge, Attitudes, And Behaviors Related To Fetal Alcohol Spectrum Disorders, Sarah L. Dewane Apr 2010

Alaskan Physicians' Knowledge, Attitudes, And Behaviors Related To Fetal Alcohol Spectrum Disorders, Sarah L. Dewane

Theses (Unassigned)

Fetal alcohol spectrum disorders (FASDs), caused by maternal consumption of alcohol during pregnancy, constitute the leading known preventable birth defects in the US. Given high prevalence rates and lifetime costs of FASDs in Alaska, it is imperative that healthcare providers have an adequate foundation of knowledge related to FASDs, as well as a strong sense of self-efficacy vis-a-vis their personal capacity to engage in primary and secondary prevention activities. The purpose of this study was to examine Alaskan physicians' self-reported levels of knowledge, attitudes, and practice behaviors related to FASDs, and identify effective ways to educate and train physicians about …

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Resource Partitioning Among Sympatric Stellar Sea Lions And Northern Fur Seals On Lovushki Island, Russia, Jason N. Waite Apr 2010

Resource Partitioning Among Sympatric Stellar Sea Lions And Northern Fur Seals On Lovushki Island, Russia, Jason N. Waite

Marine Biology

The competitive exclusion principle maintains that one of two non-interbreeding species occupying the same ecological niche and geographical territory will be displaced if population growth is not the same between species. Steller sea lions (Eumetopias jubatus; SSL) and northern fur seals (Callorhinus ursinus; NFS) breed sympatrically on four rookeries in the Russian Far East, creating the potential for inter-specific competition for limited prey resources. Approximately 1,000 SSL and 14,000 NFS breed on Lovushki Island in the Kuril Island chain. An additional 13,000--14,000 juvenile NFS are present during the breeding season. The partitioning of forage resources among breeding SSL and both …

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Development And Application Of A Methodology To Estimate Regional Natural Conditions For Trace Metals In Marine Sediments Of Southcentral Alaska's Coastal Region, Douglas H. Dasher Apr 2010

Development And Application Of A Methodology To Estimate Regional Natural Conditions For Trace Metals In Marine Sediments Of Southcentral Alaska's Coastal Region, Douglas H. Dasher

Marine Biology

Increasing levels of resource development and population growth along Alaska's relatively pristine coastline require responsible environmental stewardship that is based on scientifically defensible monitoring and assessment. This thesis develops a methodology to assess the spatial distribution of coastal sediment trace metals and estimate their natural condition along Alaska's coastline. Marine sediments provide a better integrated long-term signal for naturally occurring and anthropogenic chemicals than repeated water measurements. The first of three manuscripts reports on marine sediment trace metal concentrations from a probabilistic sampling survey of Alaska's Southcentral coastal region. Results are described on a proportional basis, i.e., percent of estuary …

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Idealized Modeling Of Circulation Under Landfast Ice, Jeremy Lucas Kasper Apr 2010

Idealized Modeling Of Circulation Under Landfast Ice, Jeremy Lucas Kasper

Marine Biology

Idealized analytical and numerical models are used to elucidate the effects of a spatially variable landfast ice cover on under-ice circulation. Three separate forcing mechanisms are investigated; lateral inflow onto an ice-covered shelf (an elevated sea level at the western boundary), a spatially uniform upwelling wind blowing along the seaward landfast ice edge and a buoyant inflow under the ice cover that enters the domain through the southern coastal wall. The idealized models are configured to resemble the shallow Alaskan Beaufort Sea shelf. Models show that the inclusion of landfast ice means shelf response is substantially different from an ice-free …

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Describing Forage Fish Availability In Coastal Waters Of The Kodiak Archipelago, Alaska, Lei Guo Apr 2010

Describing Forage Fish Availability In Coastal Waters Of The Kodiak Archipelago, Alaska, Lei Guo

Marine Biology

Assessing the availability of forage fishes is key to understanding fluctuations in populations of apex predators that prey upon them, including pinnipeds and seabirds in the Gulf of Alaska. In this study, multiple aspects of forage fish availability were measured in coastal waters of the Kodiak Archipelago, Alaska, in May (2004 & 2005), August (2004 & 2005), November (2006), and April (2007). Efforts were focused on four pelagic species that consistently dominated midwater trawl catches and have been described as important prey for upper trophic level predators around the Archipelago: walleye pollock (Theragra chalcogramma), Pacific herring (Clupea pallasii), capelin (Mallotus …

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Incidence And Determinants Of Birth Defects And Enzyme Deficiencies Among Live Births In Oman : A Review Of The 2005 National Register, Rajiv Khandekar, Yasmin Jaffer Apr 2010

Incidence And Determinants Of Birth Defects And Enzyme Deficiencies Among Live Births In Oman : A Review Of The 2005 National Register, Rajiv Khandekar, Yasmin Jaffer

Sultan Qaboos University Medical Journal

Objectives: In 2003, the Omani Ministry of Health Child Health Care Program initiated a national Birth Defects (BD) Register. This paper reviews the magnitude and risk factors of birth defects in children born and registered in 2005 using data from the BD Register. Methods: Pediatricians and neonatologists examined children with BDs found either during screening at birth or when attending clinics in their first year of their life. Clinical examination, laboratory, sonographic and radiological investigations were carried out. A pre-tested form was used to note personal details, type of birth defect including International Classification of Diseases-10 (ICD-10) codes of BD …

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Rabies Virus In Arctic Fox (Vulpes Lagopus): A Study Of Pantropic Distribution, Lori A. Gildehaus Apr 2010

Rabies Virus In Arctic Fox (Vulpes Lagopus): A Study Of Pantropic Distribution, Lori A. Gildehaus

Biological Sciences

Rabies is endemic in Arctic foxes, in Alaska and other Arctic regions and cold temperatures may preserve the virus in Arctic climates in infected animal carcasses. These frozen carcasses may provide a source of infection throughout winters and thereby propagate the rabies virus within animal populations in the Arctic. It was hypothesized that rabies virus antigen is present in the soft tissues of naturally infected Arctic foxes, Vulpes lagopus. Using a direct rapid immunohistochemistry test (DRIT) and a fluorescent antibody test (FAT), thirteen organ tissues from twelve naturally infected and three experimentally infected Arctic foxes were tested. All tissues, except …

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Neuroplasticity And Neurotoxicology: Central Breathing Control Following Developmental Nicotine Or Ethanol Exposure, Cord M. Brundage Apr 2010

Neuroplasticity And Neurotoxicology: Central Breathing Control Following Developmental Nicotine Or Ethanol Exposure, Cord M. Brundage

Biological Sciences

Nicotine or ethanol exposure early in development are both risk factors for Sudden Infant Death Syndrome (SIDS). I tested the hypothesis that both nicotine and ethanol may be linked to SIDS by impairing central breathing control responses to low oxygen (hypoxia) and high carbon dioxide (hypercapnia) stressors. Experiments were conducted in bullfrog tadpoles, a model system for respiratory neurotoxicology research. I addressed three specific aims: to characterize the effect of chronic ethanol on central responses to hypercapnia and hypoxia, to characterize the effect of chronic nicotine on central hypoxic responses, and to determine the persistence of hypercapnic impairments following 10-wk …

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Protein Status Of Muskoxen And Caribou In Late Winter, David D. Gustine Apr 2010

Protein Status Of Muskoxen And Caribou In Late Winter, David D. Gustine

Biological Sciences

The conservation and management of northern ungulates depends upon our understanding of the influence of habitat associations on the nutritional condition of individuals and population productivity. Adverse foraging conditions in late winter may reduce the availability of body proteins for reproduction. Therefore, assessing nitrogen (N) or protein status in late winter could be a valuable tool to monitor populations of northern ungulates. I collected >1,800 excreta samples to evaluate isotopic metrics of protein status [proportion of serum amino acid N derived from body N (p-AN), proportion of urea N derived from body N (p-UN), and the difference between the isotopic …

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Sentinels Of Arctic Ecosystem Health: Polar Bear And Arctic Fox, Cassandra M. Kirk Apr 2010

Sentinels Of Arctic Ecosystem Health: Polar Bear And Arctic Fox, Cassandra M. Kirk

Biological Sciences

Climate change is impacting human, wildlife, and ecosystem health in the Arctic. Currently, we lack sufficient information to fully appreciate the ramifications of these changes and are thus ill equipped for predicting, mitigating or adapting to the outcome of such impacts. Warming in the Arctic has generated a need for baseline information on biodiversity and ecosystem health such that change over time may be assessed. Sentinel species can be used to monitor and therefore, intervene to prevent adverse health outcomes before they manifest at the population level. This dissertation examines the use of polar bears (Ursus maritimus) and arctic foxes …

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Phylogeography, Ecogeographic Variation, And Evolutionary History Of The Collared Pika (Ochotona Collaris), Hayley Christine Lanier Apr 2010

Phylogeography, Ecogeographic Variation, And Evolutionary History Of The Collared Pika (Ochotona Collaris), Hayley Christine Lanier

Biological Sciences

In this dissertation I address the evolutionary history, ecogeographic variation, and phylogeography (single species and comparative) of collared pikas (Ochotona collaris). Pikas are small (ca. 150 g) lagomorphs (order Lagomorpha: rabbits, hares, and pikas) found in alpine habitats throughout much of the Holarctic. Only two of the 30 extant pika species occur in the New World. The northern of the two species, O. collaris is separated 800 km north of the American pika (O. princeps). In the first chapter, I employ recently developed molecular analytical techniques to examine when the two North American species diverged. This chapter sets the evolutionary …

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Spatio-Temporal Recruitment Dynamics Of Mountain-Dwelling Caribou In The Yukon Territory, Canada, Troy M. Hegel Apr 2010

Spatio-Temporal Recruitment Dynamics Of Mountain-Dwelling Caribou In The Yukon Territory, Canada, Troy M. Hegel

Biological Sciences

Understanding processes and mechanisms resulting in observed ecological patterns is critical information for biologists charged with effectively managing and conserving wildlife populations. In many areas across North America woodland caribou (Rangifer tarandus caribou Gmelin) populations are declining, as are caribou and reindeer populations globally. Why these declines are occurring is a key research question of biologists and managers. I investigated factors influencing recruitment of mountain-dwelling woodland caribou using long-term time series from ten herds (populations) in the Yukon Territory, Canada (Yukon). Recruitment was indexed by the calf:cow ratio observed during the fall breeding season using data collected during aerial monitoring …

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From Forest To Tundra: Historical Biogeography, Floristic Diversity And Nucleotide Variation In Balsam Poplar, Amy L. Breen Apr 2010

From Forest To Tundra: Historical Biogeography, Floristic Diversity And Nucleotide Variation In Balsam Poplar, Amy L. Breen

Biological Sciences

The North America boreal forest extends across more than 10� of latitude from central Labrador to interior Alaska. Periods of major climate fluctuations, including glacial and interglacial cycles, drove major migrations in the Quaternary history of the boreal forest. Beringia, the unglaciated region between the Lena and Mackenzie rivers, is recognized as an important refugium for arctic plants during the last ice age, but its role for boreal trees remains controversial. The paleobotanical record indicates Populus balsamifera (balsam poplar) survived within Beringia during the last glacial. My research employed an interdisciplinary approach, combining techniques in the fields of ecology, evolution …

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Gyrfalcon Breeding Biology In Alaska, Travis L. Booms Apr 2010

Gyrfalcon Breeding Biology In Alaska, Travis L. Booms

Biological Sciences

This dissertation addresses specific research needs identified by a panel of experts on Gyrfalcon biology and conservation convened on 3 September, 2003 at the Raptor Research Foundation Scientific Conference in Anchorage, Alaska. The first chapter is a significant update and revision of the 1994 Gyrfalcon Birds of North America (BNA) species account, using all published papers and available grey literature from 1994--2007 and personal expertise from over 3,000 hours of coordinated observations. The second chapter reports results from a spatially explicit model, based on the best available compiled data from Alaska, that predicted Gyrfalcon breeding distribution and population size across …

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Nutrient And Contaminant Dynamics In The Marine Food Web Of Kotzebue Sound (Alaska), Sara K. Moses Apr 2010

Nutrient And Contaminant Dynamics In The Marine Food Web Of Kotzebue Sound (Alaska), Sara K. Moses

Biological Sciences

The objectives of these studies were to document nutrient and contaminant concentrations in upper trophic level organisms of the Kotzeue, Alaska marine food web; address associated risks and benefits to human consumers of these species; understand the drivers of nutrient and contaminant patterns and concentrations; and test the limitations of chemical feeding ecology tools used to trace nutrient and contaminant pathways within this food web. Tissues of subsistence harvested animals were analyzed for nutrients, contaminants and stable isotopes (delta13C and delta15N). Foods derived from sheefish (Stenodus leucicthys) and spotted seal (Phoca largha) provide numerous essential nutrients, with limited risk from …

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Biotic Pest Damage Of Green Alder (Alnus Fruticosa ): Susceptibility To A Stem Disease (Valsa Melanodiscus) And Functional Changes Following Insect Herbivory, Jennifer K. Rohrs-Richey Apr 2010

Biotic Pest Damage Of Green Alder (Alnus Fruticosa ): Susceptibility To A Stem Disease (Valsa Melanodiscus) And Functional Changes Following Insect Herbivory, Jennifer K. Rohrs-Richey

Biological Sciences

Since the late 1990s, researchers have been predicting that a warming climate will lead to higher levels of plant disease damage. This appears to be the current trend in the boreal region; however, the level of complexity inherent to plant-pest interactions makes it difficult to make predictions across plant-pest systems. This study focuses on a boreal shrub in Alaska, Alnus fruticosa, which is currently a host to several insect and fungal pest species that are either already at epidemic status or have recently achieved epidemic status on other Alnus species in Alaska. Against the backdrop of a warming boreal forest, …

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