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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

A qualitative analysis of clinical records from a trauma response program for families exposed to violence

Behan, Kathleen G 26 April 2012 (has links)
This dissertation is a qualitative secondary content analysis of clinical records collected for the Spokane Safe Start Project in Spokane, Washington, a program designed to offset trauma in children exposed to domestic and intimate partner violence (IPV). The Centers for Disease Control and the World Health Organization have identified intimate partner violence (IPV) as a health policy issue. Most studies of intimate partner violence and children exposed to violence have used samples from domestic violence shelters, large phone-based community surveys, or convenience samples such as college students. Currently, studies of families that have experienced intimate partner violence and received services in their homes do not exist. As such, the process and effects of intimate violence in families residing in their homes have not been identified. The purpose of this study was to identify the structural issues, factors affecting service engagement, family characteristics, and factors promoting resiliency in families that experienced intimate partner violence and were served by the Spokane Safe Start Project in Spokane, Washington, a program designed to offset trauma in children exposed to caregiver intimate partner violence. To this end, the four research questions were: 1) What are the underlying structural problems that affected these families? 2) Is family functioning at intake associated with the length of time with the program? 3) Of the families that engaged with Safe Start for at least five face-to-face contacts, what are the caregiver and/or family characteristics that seem to indicate the presence or absence of resilience in the caregivers? This study involved the analysis of the clinical case records of 30 families that received Spokane Safe Services. The primary source of data for this study came from the narrative portions of the electronic ACCESS and written client clinical records. The Spokane Safe Start clinical narratives served as a record of clinician observations, interactions, and service delivery to families greatly affected by intimate partner violence. Using the bio-ecological perspective and family systems theory as the theoretical frameworks to understand intimate partner violence and its effects on children, data analysis and synthesis, I used qualitative content analysis thematic analysis, and data matrices. In essence, this is a multiple case study producing "context-dependent knowledge" that is vital to develop ecologically sound interventions to address intimate partner violence and its effects on families (Flyvbjerg, 2006, p. 221). This study revealed three main findings. Families encountered roadblocks in the form of environmental and individual obstacles. These obstacles included family-of-origin dynamics, severe financial problems, and individual issues such as relationship ambivalence and substance abuse that posed serious limitations to developing resilience. Parent-child interactions were strained and difficult in most families. The majority of children experienced chronic IPV and many had a history of maltreatment as well. Although many parents were concerned about the future wellbeing of their children, they also had difficulty reflecting on their children’s emotional needs and experiences. Evidence of resilience in the case narratives was quite limited. There was evidence, one particular clinician's model of service provision was more successful at engendering resilience than that of the other clinicians. Results were triangulated with the extant literature and previous quantitative studies conducted by Washington State University on the Spokane Safe Start data indicating the results of this study are trustworthy and credible. This study makes an important contribution to the family violence literature and may serve as a resource for policy and program development. / Graduation date: 2012
82

Establishment of concentration ratios for riparian and shrub steppe areas of the eastern Washington Columbia basin

Napier, Jonathan Bamberger 12 September 2012 (has links)
Concentration ratios are used to determine the transfer of nuclides from soil to biota to fauna. Some nuclides have limited associated data though, this has not prevented predictions from being performed at sites without associated data. These ratios are site specific and are not fully applicable when applied to other locations. A recent literature review for a waste repository performance assessment determined that a significant portion of the environmental data was based on recursively published material. To address this deficiency neutron activation analysis (NAA) was used to determine concentration ratios of certain biota. Three sites, two riparian and one shrub steppe, were sampled in the eastern Washington Columbia basin, near the Hanford site. Two hundred and fifty eight samples of opportunity were collected. This included 15 soil samples, 10 water and sediment samples, 40 different species of biota, and 2 terrestrial animal species and 3 aquatic animal species. These samples were prepared for NAA by drying, weighing, and in certain cases ashing to improve detection efficiency. After activation, the samples were placed in a HPGe detector to perform spectral analysis. The concentration results of 26 elements of interest are presented, along with newly established concentration ratios for all of the species sampled. / Graduation date: 2013
83

Indicators of Nutrient Limited Plankton Growth in Lakes Near Mount Saint Helens, Washington

Carpenter, Kurt Davis 06 December 1994 (has links)
Several lakes located in the blast zone of the 1980 eruption of Mount St. Helens were studied to determine if the plankton in the lakes were limited in their growth by nitrogen or phosphorus availability. Long term nutrient enrichment experiments were performed on lake water from five lakes and measures of chlorophyll-a, carbon fixation, and nutrient uptake were used to evaluate the extent of limitation. Nutrient concentrations, ratios, and uptake from 14 lakes provided additional evidence for limitation by nitrogen and/or phosphorus. The physical, chemical, and biological characteristics of the lakes were also examined to monitor the return of these lakes to pre-eruption conditions. Lakes heavily impacted by the 1980 eruption (Ryan, Fawn, and Hanaford Lakes) and newly formed Castle Lake produced positive responses to nitrogen additions, reflecting the continuing importance of nitrogen in these lakes. Evidence for colimitation by phosphorous was apparent in some of the lakes. Venus Lake, located near the fringe of the blast zone received less organic debris and responded only with phosphorus additions. Evaluations of nutrient depletion from the photic zones of these lakes during the growing season supported the results from the bioassays. Two measures of growth (chlorophyll-a and carbon fixation) often responded differently to enrichment, suggesting active algal and bacterial communities in some of the lakes. Qualitative measures of alkaline phosphatase activity normalized to chlorophyll-a indicated that those lakes which contained the highest dissolved organic carbon and bacterial counts following the eruption had higher alkaline phosphatase activities than less impacted lakes, suggesting bacterial enzyme production. Alkaline phosphatase activity confirmed that phosphorus limitation was more severe in lakes having less soluble reactive phosphorus. Most of the lakes appear to be similar to other Cascade Mountain lakes, although many have reduced dissolved oxygen concentrations in the bottom waters during stratification. Incomplete mixing of these lakes during periods of circulation may regulate the decomposition of the organic material and hence, full recovery of these lakes.
84

The Biogeochemistry of Lakes in the Mount St. Helens Blast Zone

Menting, Victor Lee 10 February 1995 (has links)
Dilution and ash weathering are the most important processes controlling the ion chemistry of lakes in the Mount St. Helens blast zone. Gibbs' models indicated total dissolved solids were decreasing as a result of dilution from high precipitation and runoff and the lakes plot in the rock weathering dominated region. Plots of theoretical dilution curves indicated a decline in ion concentrations as a result of dilution. Ion concentrations followed the exponential decline predicted by the dilution curve, although concentrations were higher than predicted by the curve. Increased concentrations were a result of the rapid weathering of ash in basins and on lake bottoms. Rapid weathering of ash in lake watersheds and on lake bottoms continues to influence the ionic concentrations of the lakes. In general, sodium and potassium have declined at a much faster rate than calcium or magnesium. Slower relative declines in concentrations of calcium and magnesium were a result of more rapid rate of leaching of calcium and magnesium from the ash. Ash in the watersheds will continue to be a major contributor to the overall ion chemistry of the lakes until such time as the watersheds are stabilized by vegetation and a permanent soil layer. Ash on lake bottoms will be unavailable as sources of ionic constituents when it becomes buried within deep sediment layers. Ion concentrations observed in study lakes affected by the eruption were similar to those observed in control lakes with few exceptions. Although ion concentrations in affected lakes have declined to values observed in control lakes, most were at higher concentrations than the regional means. Several functions of the ion chemistry were used to correlate planktonic community structure to lake ion chemistry. The data suggested ion chemistry was not influencing biological community structures as no patterns emerged. Analysis of diatom populations with respect to monovalent:divalent cation ratios showed no correlation.
85

Beach Response to Subsidence Following a Cascadia Subduction Zone Earthquake Along the Washington-Oregon Coast

Doyle, Debra Lee 13 June 1996 (has links)
Beach shoreline retreat induced by coseismic subsidence in the Cascadia subduction zone is an important post-earthquake hazard. Sand on a beach acts as a buffer to wave attack, protecting dunes, bluffs and terraces. The loss of sand from a beach could promote critical erosion of the shoreline. This study was initiated in order to estimate the potential amount of post subsidence shoreline retreat on a regional scale in the Central Cascadia Margin. The study area is a 331 km stretch of coastline from Copalis, Washington to Florence, Oregon. Several erosion models were evaluated, and the Bruun model was selected as the most useful to model shoreline retreat on a regional scale in the Central Cascadia Margin. There are some factors that this model does not address, such as longshore transport of sediment and offshore bottom shape, but for this preliminary study it is useful for estimating regional retreat. The range of parameter input values for the Bruun model include: the depth of closure (h) range from 15 m to 20 m water depth; the cross-shore distance (L) range from 846 m to 5975 m; and the estimated subsidence amount (S) range from O m to 1.5 m. The minimum to maximum range of post-subsidence shoreline retreat is 142 to 531 m in the Columbia River cell, 56 to 128 m in the Cannon Beach cell, 38 to 149 m in the Tillamook cell, 25 to 91 m in the Pacific City cell, 11 to 126 m in the Lincoln City cell, 30 to 147 m in the Otter Rock cell, 0 to 165 m in the Newport cell, 0 to 76 m in the Waldport cell, and 0 m in the Winchester cell. Results of the study suggest that many of the beaches in the study area are at risk of beach and personal property loss. Beach communities could limit the amount of potential damage in these areas through coastal zone planning.
86

Distribution and life history of the spiny dogfish (Squalus acanthias) off the Oregon and Washington coasts

Richards, Jaclyn M. 24 May 2004 (has links)
This study examines the spatial and temporal distribution and life history of the "offshore" component of the Northeastern Pacific spiny dogfish (Squalus acanthias) population. Distribution was examined in relation to latitude, depth, the Columbia River plume and large-scale climate changes. Fishery and survey data indicate that the Northeastern Pacific spiny dogfish population has a broad range along the Washington and Oregon coasts, with the highest abundance occurring off the northern Washington and central Oregon coasts. Catches, however, were patchy throughout the 37-year period of available survey data. In terms of depth, the greatest abundances of spiny dogfish were captured in shallow waters (55-184 m). An examination of the influence of the Columbia River plume using a generalized additive model (GAM) indicated that the fish were influenced significantly by the salinity, chlorophyll and surface temperature patterns associated with the plume, preferring the oceanic zone to the plume zone. In contrast, there was no indication that the catch-per-unit-effort of spiny dogfish was influenced by the Pacific Decadal Oscillation (PDO) or the El-Niño (ENSO) over 24-year period of the National Marine Fisheries (NMFS) triennial shelf groundfish survey (1977-2001). The multi-cohort age structure of the population, due to the spiny dogfish's late age at maturity and long lifespan, as well as the low fecundity make it difficult to detect the loss of a single cohort or two when examining abundance trends. Moreover, effects on abundance may be time-lagged, especially if, as is likely, the youngest cohort(s) is the most vulnerable life stage. Their absence would not become evident until they were large enough to have been captured by the survey gear. Sensitive abundance data and/or age-structured data would be needed to identify a pattern. I quantified the age, maturation and fecundity of the spiny dogfish and use these data to develop an age-structured matrix model to examine the sensitivity of the population's growth rate to changes in mortality (i.e. fishing). Female spiny dogfish in this population have an average age at 50% maturity of 28 years and males 20 years. Average length at 50% maturity was 85.0 cm for females and 71.5 cm for males. Female fecundity was extremely low, averaging eight pups per clutch biennially and ranging from four to 14. The number of pups increased with length, but not age. Using these data, a deterministic, female-based model was developed. Asymptotic population growth rate (λ) was determined to be very low, 1.01, and comparable to population growth rates calculated for "coastal" populations. When fishing mortality was incorporated into the model, the fishery was only sustainable when exploitation was low and strict size limits enforced. When fecundity was doubled, the population growth rate increased from 1% to 3% per year. This 33% increase in population growth was equivalent to the effect of a decrease in the age at first maturity of three years. Given that responses to changes in population demographics through shifts in fecundity or spawning frequency are likely constrained, responses would then seem likely to involve changes in age at maturity. These life history traits translate into a low potential population growth and as a consequence high susceptibility to overfishing. My findings indicate that the Northeastern Pacific spiny dogfish are relatively slow growing, late to mature, and have low fecundity and a patchy distribution, with large catches occurring off the northern Washington and central Oregon coasts in shallow waters (55-184 m). These life history traits and distributional patterns are useful in the development of population models to predict responses to environmental fluctuations or increased mortality and thus the management of the population. It is evident from my findings that periodic monitoring is necessary to track possible catch declines off the northern Washington and central Oregon coasts and prevent collapse of the population should it be targeted by a fishery and overfishing occur. / Graduation date: 2005
87

Assemblages of groundfish caught using commercial fishing strategies off the coasts of Oregon and Washington from 1985-1987

Rogers, Jean Beyer 23 February 1994 (has links)
The groundfish trawl fishery operating off the coasts of Oregon and Washington 1985-1987 caught six major assemblages of species which could be treated as units in developing mixed-species management plans. Eighty-one percent of the tows observed on commercial vessels were consistently placed in one of the assemblage designations using three multivariate techniques. Two of the assemblages were dominated by a single species, pink shrimp (Pandalus jordani) or widow rockfish (Sebastes entomelas). The other assemblages identified were: a deepwater rockfish assemblage, a deepwater Dover sole assemblage, a nearshore mixed-species assemblage, and a bottom rockfish assemblage. The assemblage designations of the consistently placed tows were predicted with an estimated 85% average accuracy using discriminant functions based on the gear used and bottom depth fished. Fishermen had different targets (intended catch) for each assemblage caught. The mixed-species assemblages had several targets, representing at least some of the dominant species in the assemblage. Targeting and discarding information indicated that fishermen did not always intend to catch the species together; there were unintentional or unavoidable catches of all the major species except for shrimp in the shrimp assemblage. Discarding occurred in all the assemblages, primarily due to unmarketable species or fish that were too small to market. Monitoring the assemblages over time could be accomplished by using the defined strategies with logbook data, particularly if the large and small rockfish categories were used to consistently separate shelf and deepwater rockfish. The defined strategies could not effectively predict the research cruise assemblages or catches; research data do not accurately describe commercial catches. / Graduation date: 1994
88

Effects of hydrology on zooplankton communities in high mountain ponds, Mount Rainier National Park

Girdner, Scott F. 06 April 1994 (has links)
Ten high mountain ponds in Mount Rainier National Park, Washington State, were studied from June through September 1992 to investigate the influences of fluctuating pond volumes on zooplankton communities. A temporary pond of short wet phase duration was inhabited by zooplankton taxa with short generation times and a crustacean taxa with the ability to encyst as drought-resistant resting bodies at immature stages of development. Relative to permanent ponds, rotifer densities typically were low in temporary ponds, although Brachionus urceolaris was abundant shortly before the ponds dried. High volume loss was associated with declining populations of crustaceans. Daphnia rosea was not present in the crustacean communities of temporary ponds after fall recharge. Deep-permanent ponds had slower copepod development and two additional large bodied crustacean taxa relative to shallow-permanent ponds. Because of their small sizes and sensitivity to environmental change, ponds such as these may provide an early signal of changes in aquatic systems from global warming. / Graduation date: 1994
89

Mycorrhizal fungi and their relationship to plant succession in subalpine habitats

Cazares, Efren 15 January 1992 (has links)
Graduation date: 1992
90

Gelidiales (rhodophyta, red algae) in British Columbia and Northern Washington : taxonomy, morphology, development

Renfrew, Dawn Elizabeth January 1988 (has links)
A study of the red algal order Gelidiales in British Columbia and northern Washington was conducted. Gelidiales are represented in the study area by four species, Gelidium coulteri, G. purpurascens, G. vagum and Pterocladia caloglossoides, and a key to identify the taxa is provided. Earlier reports of G. crinale, G. pusillum, G. robustum and G. sinicola from British Columbia and northern Washington have been shown to be misidentifications of the other taxa and are excluded from the flora. The occurrence of G. vagum in the British Columbian flora is significant because it appears to have been introduced from the northwest Pacific and now has a disjunct distribution, occurring in Japan and China and on two islands in the Strait of Georgia, British Columbia. Gelidium vagum and the Gulf of California species, G. johnstonii, are considered to be sister species. They share the unique character of monoecy (i.e. unique in the genus) and a morphological resemblance, but differ in several other characters, including arrangement of cortical cells, shape and flattening of tetrasporangial stichidia, shape of stichidial apices and position of the apical initial with respect to the adjacent cortex, presence/absence of an apical furrow and sterile margin in tetrasporangial stichidia and presence/absence of intact third order filaments in mature cystocarps. The life history of Gelidium vagum was completed in culture, only the second Gelidium species for which this has been accomplished. Gelidium vagum has a triphasic Polysiphonia-type life history with isomorphic (monoecious) gametophytes and tetrasporophytes, and carposporophytes growing on gametophytes. The rare occurrence (G. purpurascens, G. coulteri) or absence (Pterocladia caloglossoid.gametophytes in the field and the lack of successful completion of a life history in culture suggests that, whereas these species may occasionally complete a Polysiphonia-type life history in situ, vegetative or apomictic mechanisms are more important in maintaining field populations. Chromosome counts of n = 14 - 15 were made on undivided tetrasporangia of G. vagum. The pattern of spore germination in Gelidium coulteri, G. purpurascens and G. vagum is similar for carpospores and tetraspores. A single germ tube grows from the spore, the entire cytoplasmic contents of the spore evacuate into the germ tube and a wall cuts the germ tube off from the empty spore. The germ tube divides unequally to form a concave and a fusiform cell. The primary attachment rhizoid forms from a derivative of the concave cell and the sporeling apical cell forms from a fusion cell derivative. As apical organization is established, the subapical cell produces two lateral periaxial cells. Carpogonium and carposporophj'te development was followed in Gelidium purpurascens and G. vagum. The functional carpogonium is intercalary. Non-functional carpogonia divide transversely with a concave wall and become sessile and degenerate. The fertilized carpogonium consistenty forms a fusion cell by fusing with adjacent cortical cells. Fusion cell lobes cut off gonimoblast filaments that send out processes that fuse with haploid gametophyte cells of nutritive chains. Carposporangia are produced terminally and laterally by gonimoblast cells and protrude into two locules that have formed as the cortex is pushed away from the plate of second order filaments. Carpospores are released through a single ostiole in each locule. Spermatogenesis, tetrasporogenesis and rhizine morphology were studied ultrastructurally for the first time in Gelidiales. In spermatangial development, apical chloroplasts in the spermatangial mother cell are cut off by a furrow, a mechanism previously not reported in red algae for exclusion of chloroplasts from spermatangia. As the spermatangium matures, spermatangial vacuoles form from the coalescence of vesiculated endoplasmic reticulum and dictyosome-derived vesicles. Spermatangial vacuoles are discharged from the spermatangium just prior to the release of the spermatium. Stages of tetrasporangium development are marked by wall development. Prior to karyokinesis, the young tetrasporangium is dominated by a large nucleus. Following karyokinesis, chloroplasts, starch grains and dictyosomes increase in abundance, a wall layer is deposited, and dictyosomes undergo a series of morphological changes from small and flat, to large and flat producing fibrillar vesicles, to hemispherical and producing cored vesicles. At cytokinesis an electron dense wall layer is deposited around the tetrasporangium and in the cleavage furrow, and cored vesicles secrete a mucilage-like material inside this wall layer. / Science, Faculty of / Botany, Department of / Graduate

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