Now showing items 3129-3148 of 3446

• #### The significance of marine-derived biogenic nitrogen in anadromous Pacific salmon freshwater food webs

The natural abundance of the stable isotope ratios $\sp{15}$N/$\sp{14}$N and $\sp{13}$C/$\sp{12}$C expressed as $\delta\sp{15}$N and $\delta\sp{13}$C was used to trace biogenic nutrients delivered by returning adult anadromous Pacific salmon into freshwater systems. These systems were Sashin Creek, a rapidly flushing stream located on Baranof Island, southeastern Alaska and Iliamna Lake, the major sockeye salmon, Oncorhynchus nerka, nursery lake in the Kvichak River watershed, Bristol Bay, southwestern Alaska. Marine-derived nitrogen (MDN) was quantifiable by use of an isotope mixing model based on comparison of biota $\delta\sp{15}$N in areas used for spawning by anadromous salmon with salmon-free controls within the same watershed. Control periphyton (benthic primary producers) $\delta\sp{15}$N values $\sim$0 suggested that the control N pool was derived from N$\sb2$ fixation without significant recycling. In contrast, periphyton abundant in areas of intense spawning activity or carcass aggregation had $\delta\sp{15}$N $\sim$ +7. These two values were the basis for comparison of $\delta\sp{15}$N values of higher trophic level biota. A mixing model relating $\delta\sp{15}$N to MDN with trophic level was used to estimate consumer MDN through incorporation of a priori isotopic trophic enrichment factors established in the literature. Distinctive $\delta\sp{13}$C signatures along the Sashin Creek stream gradient and between Iliamna Lake littoral and limnetic production were used in concert with $\delta\sp{15}$N. Sashin Creek fishes reflected isotopic signatures of periphyton and thus production within the same stream section. Isotopic data suggested an overall importance of limnetic production in Iliamna Lake resident fish and juvenile sockeye salmon diets. Salmon eggs and emergent fry retaining the parental marine isotopic signature were distinguishable from autochthonous production derived from marine N, and appear to be a minor dietary component in both Sashin Creek or Iliamna Lake fishes. The proportion of MDN in resident fish N, including juvenile salmon after turnover of the natal N pool, was proportional to the escapement of spawners. Thus there is now direct evidence for a significant natural fertilization process: the flow of remineralized marine-derived biogenic nutrients from returning anadromous Pacific salmon into freshwater food webs.
• #### The Social Construction Of Unique Caring Relationships: Metaphors And Descriptors Of Aids And Mutuality In Buddy Dyads

This study explores how acquired immune deficiency syndrome (AIDS) is socially constructed in buddy dyads as revealed by the written metaphors and descriptors supplied by cultural members through a survey instrument. A buddy dyad consists of a volunteer caregiver and a person with AIDS (PWA). The metaphors and descriptors that the buddies recounted provide an understanding of these special relationships and the social construction of AIDS in this uniquely affected population.<p> Analysis revealed that AIDS is most often constructed as integral to community and activism in the AIDS Culture. The buddy relationship is most often constructed as a friendship rather than a caregiver/client relationship. The participants also revealed that buddy dyads are both life-affirming and significant relationships. The examination of buddies' metaphors and descriptors further suggests that their lived experience with AIDS is uniquely different than the construction of AIDS most often made by the media and the rest of U.S. culture. <p>
• #### The takin and muskox: A molecular and ecological evaluation of relationship

This research clarifies the classification of and relationship between the takin (Budorcas taxicolor) and muskox (Ovibos moschatus). Although both are social ungulates of similar body size, takins live in dense mountainous habitats at temperate latitudes in Asia, and muskoxen live in open arctic habitats in Alaska, Canada and Greenland. Morphological, paleontological and chromosome comparisons have supported a close relationship between these species and their classification within the tribe Ovibovini in the subfamily Caprinae. Previous studies, however, have not defined the genetic relationship of the takin and muskox. This project used ecological and molecular comparisons to evaluate these proposed relationships. Ecological studies in Shaanxi, China showed takins are generalists in their use of habitat and forage, but live in dense habitat in groups, ostensibly to avoid predation. Likewise, muskoxen live in groups and are generalists, but inhabit open landscapes. Some ecological and behavioral similarities appear to support the hypothesis of close relationship. In contrast, molecular studies using cytochrome b sequences from mitochondrial DNA (mtDNA) clearly separate the takin and muskox into distinct clades. Takins are more closely related to sheep (Ovis spp.) and muskoxen to the Asian goral (Nemorhaedus caudatus). Similarities between the takin and muskox appear due to convergent evolution as an adaptation to large body size. A broader comparison of cytochrome b sequences from 11 species of Caprinae supported the separation of takins and muskoxen. Unequal rates of evolution among the species precluded complete resolution of Caprinae relationships. To define differences between muskox subspecies and populations, sequences of the highly variable control region of mtDNA from 37 muskoxen were compared. Delineation of muskox subspecies is a critical issue due to the potential for interbreeding of indigenous Canadian (O. m. moschatus) and introduced Alaskan (O. m. wardi) populations of muskoxen as range expansion occurs. Variability between these populations was so low differences could not be detected with this comparison. I suggest a history of genetic bottlenecks has reduced genetic variability of muskoxen to low levels and neither populations nor subspecies can be defined from control region sequences.

• #### The Turnover Of 75-Selenium - Selenomethionine As An Indicator Of The Status Of Protein Metabolism In Reindeer (Rangifer Tarandus) (Degradation Rate, Reincorporation, Reutilization)

The turnover of a single injection of ('75)Se-selenomethionine (('75)SeM), a radio-labeled seleno-analog of the amino acid methionine was used to estimate protein turnover, the irreversible loss of protein nitrogen, in reindeer. ('75)Se-selenomethionine turnover was measured in nine adult female reindeer grazing on natural forage during winter (November-April) and summer (July-August). ('75)Se-selenomethionine turnover was two to four times higher during summer than during the winter months. Seasonal changes in ('75)SeM turnover were believed to be due primarily to seasonal changes in protein and/or methionine intake. The relationship between the intakes of protein and methionine and the turnover of ('75)SeM was determined in ten pen-fed reindeer. Reindeer consumed one of three rations containing 3, 11, or 18 percent crude protein. This resulted in daily crude protein intakes of 1.6, 5.1, or 8.2 g per kg ('0.75) b.w. and daily methionine intakes of 0.01, 0.06, or 0.12 g per kg ('0.75) b.w. ('75)Se-selenomethionine turnover was four times higher for reindeer with high protein and methionine intakes than those reindeer consuming low levels of these nutrients. High positive correlations were found between ('75)SeM turnover and the intake of crude protein and methionine. The method of using ('75)SeM as an indicator of protein turnover showed a good empirical relation, but application to other biological conditions should be accompanied by calibration trials.
• #### The universal duty to alleviate inflicted suffering: An ethical grounding for Siu's new discipline of Panetics

Dr. Ralph G. H. Siu has challenged the intellectual community with a call for a new academic discipline that he calls Panetics (from the Pali word paneti meaning 'to inflict'). Panetics is the study of humanly engendered suffering, its causes and methods of alleviation. Suffering is measured in units called dukkhas (from the Pali word dukkha meaning suffering), which are the product of the intensity of pain and the amount of time the pain is endured. The result will be in terms of units of suffering, i.e. the dukkha. Dr. Siu has argued that this new academic discipline is not a forum for the discussion of theoretical ethics nor is there any implied moral precept which prescribes moral action. It will be shown that not only are there prescriptions for moral action embedded in panetic talk but that the entire discipline rests on moral presuppositions. In addition, a normative ethic is implied in the purpose of the Panetic Calculus, and this will be clarified. It will be shown that Dr. Siu's approach to the "New Utilitarianism" constitutes a form of negative utilitarianism, which may provide an 'ethical ground' upon which to rest what will be called the Principle of Least Inflicted Suffering. It will be argued that this Principle can be universalized because the 'ethical ground' upon which it rests is composed of a human universal (viz, human suffering), a component of all human 'forms of life.'
• #### The Weathering Of Placer Gold And The Quaternary Geology Of Valdez Creek, Clearwater Mountains, Alaska

Placer gold grains collected from six paleochannels in the Valdez Creek drainage, south-central Alaska, were deposited during successive interglacial/interstadial intervals since the mid-Early Pleistocene. Statistical analysis of grain size, shape, grain surface characteristics, and the gold content of the interior and exterior of the gold grains determined by electron microprobe analysis demonstrates that the grains were affected by both mechanical and chemical weathering, and that the weathering increased with time. Etch pits, observed under a scanning electron microscope, are a ubiquitous feature of the grain surfaces. Grain surfaces average 26.7% richer in gold than the interior of the grains. The gold content of the surface of the grains increases with age. No high gold fineness rims were observed in cross section on the grains. This evidence indicates that the gold grains experienced corrosion. <p>
• #### The white dog year

This creative thesis, a book-length poetry manuscript titled "The White Dog Year," explores issues of gender, sexuality, family, mental health, violence, and rural poverty. In the personal and confessional tradition, the poems in the thesis are both lyrical and narrative. They are in dialogue with a variety of poets, including Robert Frost, W.B. Yeats, Elizabeth Bishop, Sylvia Plath, and, more contemporarily, Sharon Olds, Carolyn Forche?, Hadara Bar-Nadav, Eduardo Corral, and Allison Seay. "The White Dog Year" exists between imagination and reality, what I refer to as a dreamscape, which is comprised of the physical places where I have lived (Virginia, Ohio and Alaska), my memory of these places, and how I recreate them. This thesis also investigates the relationship between memoir and poetry, and how personal narratives can be told primarily through language, lyricism, and poetic fragments.
• #### Theoretical And Experimental Analysis Of Two-Phase Closed Thermosyphons

This work presents an analytical and numerical model of a long inclined two-phase closed thermosyphon, known as a hairpin thermosyphon, which is representative of a new configuration for thermosyphons used in arctic applications. A laboratory experiment and a full scale road experiment along with associated modeling are described in detail. The laboratory experiment studies the condensation heat transfer performance of carbon dioxide inside the thermosyphon condenser under conditions of limited heat flux. The operating condition is not far from the critical point for carbon dioxide, which has a significant impact on the condensation heat transfer. An experimental correlation is developed to predict the carbon dioxide condensation heat transfer performance under these specific conditions. The full scale road experiment studies the overall performance of hairpin thermosyphons under actual field conditions. The model is a quasi one-dimensional formulation based on two-dimensional two-phase flow simulations at each cross section. The proposed model is useful for predicting steady state system operating characteristics such as pressure, temperature, liquid film thickness, mass flow rate, heat flow rate, etc., at local positions as well as over the entire system. The comparison of the modeling predictions with both laboratory and field experiments showed a strong correlation between modeling predictions and experimental results.
• #### Theoretical investigations on strategies for sampling meteorological and chemical field quantities in smoke plumes using UAVs

Wildfires emit large quantities of pollutants that decrease the air quality in the atmospheric boundary layer. Understanding the chemical makeup of a fire plume is beneficial for air quality studies and for air quality forecasting in communities. To be able to understand the chemical composition, Unmanned Aerial Vehicles (UAVs) should be flown into plumes with an air quality instrumental payload. Before such flights can be completed it is crucial that the flight paths will allow for a complete understanding of the chemical concentration distributions within the plume. To develop such a flight path, with respect to flight altitude, direction and speed the UAV should travel at for examining a wildfire plume in Interior Alaska, output from the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem) was used and was considered to be the true atmospheric conditions over the UAV measurement domain. For this thesis simulations were for 3-10 August 2009 of the Alaska fire season, centered in Interior Alaska. Focus for the UAV study was on the smoke plumes from the Crazy Mountain Complex fires near Circle, AK. Based on the results from the comparison of different flight altitudes, sampling patterns, and speeds of the simulated UAV flights, recommendations can be made for the use of UAVs in a field campaign into a wildfire plume in Interior Alaska.
• #### A theoretical study of type Pi 2 geomagnetic micropulsations

Pi 2 pulsations are long period magnetic oscillations superimposed onto the geomagnetic field. They are usually associated with the onset of auroral substorms. To gain an understanding of the generation of Pi 2 pulsations, an instability mechanism and a transient response mechanism are studied. The instability mechanism results from a deceleration of magnetospheric convection in the plasma sheet while the transient response mechanism arises from an enhancement of magnetospheric convection in the plasma sheet. Both mechanisms are reviewed and a one-dimensional wave equation is solved numerically to model the transient response mechanism. The numerical computations indicate that a rapid enhancement of the magnetospheric convection will launch Alfven waves which will produce an oscillating current in the ionosphere. Model results for the transient response mechanism indicate that the oscillating current can produce Pi 2 pulsations with periods that compare favorably with ground based measurements.
• #### Theoretical, experimental and numerical simulation study of a radially injected barium disk

An Investigation of the dynamics and stability of a high-altitude radial barium plasma injection is performed using theoretical and numerical simulation methods. The barium plasma cloud, injection experiment was conducted on March 16, 1980 and produced several interesting phenomena: (1) Three distinct rings of barium containing irregularities exhibiting collective motion; (2) A region of plasma depletion at the location of injection; (3) A structure of approximately eighteen distinct barium ion rays emanating from the injection location. A collisionless, electrostatic particle simulation model is used to understand the behavior of the plasma, indicating that the initial plasma deformation develops due to an E x B azimuthal velocity shear instability. A theoretical model used for a stability analysis of the plasma is formulated based on the number density distributions of the electrons and ions obtained from the numerical simulation results. The linear stability analysis shows that the number of unstable azimuthal modes created by the velocity shear instability is dependent upon the amount of charge separation occurring in the expanding plasma.
• #### Therapeutic multi-faceted relationships in rural Alaska

In rural Alaska, avoidance of dual relationships is impossible and may be culturally inappropriate; Alaska Native counselors live and work in communities where they are reared, educated, married, had children, and built their homes. These counselors have layers of relationships with relatives, friends and coworkers outside of the therapeutic alliance. In this study I interviewed six Alaska Native rural counselors and three clinical supervisors regarding the nature of their multi-faceted relationships, stressors of these on the counselor and ways of managing these stressors. Counselors stated that the multi-faceted relationships are a part of their daily life. They primarily manage these stressors through self-care techniques ranging from establishing clear boundaries to prayer and mediation to debriefing with a supervisor. Most Euro-American mental health professionals will never know the experience of counseling only their family and friends in the hometown where they were born and raised. However, for those counselors who live and practice in rural America this study should offer encouraging strategies for managing multi-faceted relationships.
• #### "There are just a few of us, but we are all important": responses to a disaster preparedness survey in Interior Alaska river villages

This survey explores individual perspectives about disaster preparedness in Interior Alaska villages. The results will be used to create a new, locally relevant preparedness outreach flyer for distribution across the Interior Alaska region. Modern Red Cross preparedness fliers use the "Be Red Cross Ready: Get a Kit, Make a Plan, Be Informed," flyer to educate people on useful preparedness behavior. This is also the standard across the United States used by the Federal Emergency Management Agency and other government agencies. But is the information contained within the "Get a Kit, Make a Plan, Be Informed" flyer really applicable to life in small, remote, Alaskan communities? Many of these communities are highly isolated according to the standards applied to the rest of the country: they experience often-extreme environmental conditions, and are composed of indigenous people who have their own worldview and concept of risk and community values. In order to effectively prepare people in villages for disasters, everything must be reconsidered to fit this Alaskan setting. Key findings from this survey project include: the importance of outdoor survival gear and cold-weather gear in emergency kits; the need for more written small community emergency plans; and the need for cultural competency training for disaster response professionals and volunteers.
• #### There are no hurricanes in Michigan

There are No Hurricanes in Michigan is a short story collection of rural noir predominantly set in Southwest Michigan, a region of both beauty and blight. These stories inhabit many places: trailers nestled in the forests of Allegan County, blueberry farms adorning the shores of Lake Michigan, decrepit barns, ornate courtrooms and the historic districts of Kalamazoo. The contrasts of these natural settings are captured in the collection's fictional characters. Rough-neck romantics, doped-up lawyers, principled abusers, repentant veterans, and hopeless farmers all navigate their own stories of violence, death and ruin. In doing so, each character exposes, or enacts, a combination of social issues unique to rural America. These issues include drug and alcohol abuse, agricultural exigency, domestic violence, sexual assault, violent crime, suicide, isolation, low educational attainment, poverty and unemployment. To lay these issues bare, while also underscoring their characters' redeeming integrities, each story largely relies on juxtaposition, symbolism, and personification for rhetorical effect.