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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.
101

An Investigation into the Interaction of Psychopathology, Personality, and Sleep Disturbances in Clients from a Community Mental Health Center

Bates, Allison Lynn 01 January 2010 (has links)
Studies have found a relationship between psychopathology and sleep disturbances, as well as between psychopathology and personality traits. What has not received attention to date, however, is the interplay amongst all three factors: psychopathology, sleep disturbances, and personality characteristics. This study explores the interaction amongst the three areas, as well as examines specific relationships between psychopathology and sleep disturbances and personality and sleep disturbances. Forty clients were recruited from a community mental health center. Participants were receiving outpatient psychological services, were over 18, and did not have a diagnosis of active psychosis or mental retardation. Participants completed 9 questionnaires covering items about demographic information, psychological concerns, sleep, personality style, and social desirability. They received a $10 gift card upon completion of the study. Participants had a mean age of 47.6 (70% female, 77% Caucasian). Results indicated that individuals with more severe psychopathology had poorer sleep quality and greater insomnia severity; however, participants with longer histories of psychopathology did not have more dysfunctional beliefs and attitudes about sleep. Participants with more extraverted personality styles did not sleep less than individuals who were less extraverted, and those who were more neurotic did not exhibit poorer sleep quality or greater insomnia severity. Lastly, when examining the relationship amongst all three factors, it was found that psychopathology may be a better predictor of sleep disturbances than personality is (depending on how sleep was assessed), and personality and sleep disturbances are both significant predictors of psychopathology. The results reinforce the interplay amongst psychopathology, personality, and sleep disturbances. Mental health professionals may want to place greater importance on the role of sleep in the treatment of psychological and personality disorders. Future research could replicate the study with a larger sample, utilize a different personality measure, or follow participants longitudinally from the start of their mental health treatment.
102

Interacting Disturbances in the Boreal Forest and the Importance of Spatial Legacies at Multiple Scales

James, Patrick Michael Arthur 03 March 2010 (has links)
Forest disturbances and the spatial patterns they create affect ecosystem processes through their influence on forest vegetation from individual trees to landscapes. In the boreal and mixed-wood forests of eastern Canada the main agents of disturbance are logging, fire, and defoliation by the spruce budworm (SBW, Choristoneura fumiferana). These disturbances are similar in that they remove forest biomass and influence forest succession but also distinct in that logging creates patterns that are different than those created by natural disturbances. All disturbances are indirectly linked to each other through their mutual effects on forest spatial structure and succession. Through such feedbacks, spatial disturbance legacies can facilitate or constrain further disturbances, including forest management. Surprisingly, the long term spatial consequences of interactions among multiple natural and anthropogenic disturbances remain largely unexplored. This thesis investigates how, and at what spatial scale, legacies in forest composition and age structure influence natural disturbance dynamics, and how natural disturbances constrain forest management. I address four specific questions: (i) For how long do spatial legacies of different forest management strategies persist on the landscape? (ii) How do interactions among logging, fire, SBW, and succession affect timber availability and long term forest patterns in age and composition? (iii) How do these patterns differ from those created by each disturbance individually? And, (iv) How can management be used to reduce the extent and severity of fires and SBW defoliation through the manipulation of forest structure? The key scientific innovations of this thesis are: (i) Characterization of the duration and influence of spatial legacies on forest disturbances and sustainability; (ii) Development of a dynamic spatial forest simulation model that includes distinct successional rules that respond to different types of disturbance and shifts in disturbance regimes; and, (iii) Development and application of a wavelet-based significance testing framework to identify key scales of expression in forest spatial patterns. These innovations provide a scientific basis for landscape level forest management strategies designed to reduce the long term impacts of defoliating insects and to meet multiple objectives.
103

Effects of restoration on instream bryophyte communities : Monitoring of two different restoration techniques in the Vindel River system

Sandberg, Lisa January 2015 (has links)
Ecological restoration is the practice of assisting the recovery of a degraded, damaged or destroyed ecosystem. The aim of this study was to analyse the effects of two different restoration techniques on instream bryophyte abundance, species richness and diversity as well as community composition, in streams channelized for timber-floating. Instream bryophytes were collected from 10 tributaries of the Vindel River in boreal northern Sweden, from five stream reaches each of channelized reaches, which had not been restored; reaches restored in the early 2000s, using best-practice techniques; and reaches restored in the early 2000s and then re-restored in 2010 using the new “demonstration” techniques. A multitude of environmental variables were also measured at the sites. Bryophyte abundance was lower in demonstration restored sites than unrestored or best-practice restored sites but no significant difference was found in bryophyte species richness, diversity or species composition. Environmental variables correlated with bryophyte abundance, species richness, diversity and composition largely reflected effects of restoration, and probably the disturbance associated with restoration. Small sediment grain sizes also had a negative effect on species richness. Other environmental variables that influenced bryophyte species composition were the large-scale factors of latitude, longitude and elevation and reach-scale factors of potassium concentration and light absorbance. It is not yet possible to fully evaluate the effectiveness, in terms of bryophyte response, of the new demonstration restoration compared with best-practice since the recovery time between them differs and has not been sufficient. Long-term monitoring of the effects of restoration is needed in order to better evaluate success.
104

Ecological impacts of Highveld gerbils (Tatera Brantsii) on a rehabilitated ash disposal site / Nevil Ian Wright

Wright, Nevil Ian January 2006 (has links)
Tatera brantsii was numerically dominant in the small mammal community on the plateaux of the rehabilitated ash disposal sites of ESKOM's Hendrina Power Station in 1998 and 1999 (Vermaak 2000). The species seemed well adapted to exploit this environment and, through biopedturbation, had altered the topsoil structure and chemistry. The consequences of this and other activities also affected the rehabilitated plant community of the PFA-dam habitat. Burrowing appeared limited to just under the topsoil layer, and seemed more extensive than burrows of this species in natural ecosystems. The burrow system architecture was mapped and quantified, and localised increases in nitrates, phosphorous and organic carbon in immediately associated substrate were noted. However, this substrate enrichment was transient, and disappeared following the abandonment, and subsequent collapse of burrow systems, when gerbil colonies migrated away from the area. The mixing of soil horizons also resulted in a more homogeneous substrate, which was more friable, and thus drier. The high pH and salinity of the topsoil layer in areas undisturbed by gerbil burrowing, and concentrations of particular elements associated with either the topsoil covering or the ash, were reduced as a consequence of substrate mixing in disturbed areas. Gerbil impacts on the substrate of this habitat seemed to promote pedogenesis, eliminating the sharp distinction between the topsoil covering and the ash below, but the re-exposed ash of the burrow mounds would become subject to erosion, and reduce the effectiveness of the rehabilitation effort. Gerbil activities increased the number of plant species, especially ruderal forbs, comprising the plant community of the PFA-dam habitat, but plant community diversity was not significantly increased. However, numerical dominance by few tussock grass species was diminished , possibly reflecting burial under mounds of excavated substrate. The biomass and cover of some grass species were reduced in areas of gerbil impacts, and plant lifecycles appeared to be completed sooner in areas affected by gerbil activities. These effects may be as a result of the drier substrate produced following the collapse of the extensive network of abandoned burrows. The succession of this plant community towards an underutilised grassland state, the expected outcome of the rehabilitation effort, was minimally affected by gerbil activities. The effects of T.brantsii activities in this PFA-dam habitat were not as distinct as the effects noted by other authors studying fossorial rodent impacts in less disturbed habitats. This could be because further disturbances in this habitat would merely add to the currently disturbed state, whereas disturbance in more natural habitats, would show more of a change from the initial state. / Thesis (M.Sc. (Zoology))--North-West University, Potchefstroom Campus, 2007.
105

Investigating patterns among demographics, identification practices, interventions, and educational outcomes for students with serious emotional disturbance.

Gonzalez, Christine 08 1900 (has links)
This study explored potential patterns of association among the demographic characteristics, identification practices, educational interventions, and educational outcomes for students with serious emotional disturbance (SED) as well as specifically investigated the impact of age at identification with SED and the presence of co-occurring disabilities. Data was gathered from the educational records of students with SED in seven rural to semi-rural districts in Texas. Demographic information included gender, ethnicity, age at identification with SED, and identification with co-occurring disabilities. Identification variables that were investigated include the five federal qualifying criteria for SED, IQ score, and BASC and/or CBCL scores. Intervention variables that were explored included placement setting, restrictiveness of placement setting, type of related services provided, parental attendance at multidisciplinary team meetings, number of multidisciplinary team meetings, and total time spent in special education as a student with SED. Outcome variables that were examined included achievement levels in reading and math, attendance, special education status, and grade retention. Results suggested that earlier identification with SED is related to placement in less restrictive settings, achievement within two years of grade level in reading, and lower average number of absences. The presence of co-occurring disabilities in addition to SED is associated with placement in more restrictive settings and with achievement that is two or more years below grade level in reading and math. Additional findings and implications for future research as well as for current practice are discussed.
106

Prototype campaign assessment of disturbance-induced tree loss effects on surface properties for atmospheric modeling

Villegas, Juan Camilo, Law, Darin J., Stark, Scott C., Minor, David M., Breshears, David D., Saleska, Scott R., Swann, Abigail L. S., Garcia, Elizabeth S., Bella, Elizabeth M., Morton, John M., Cobb, Neil S., Barron-Gafford, Greg A., Litvak, Marcy E., Kolb, Thomas E. 03 1900 (has links)
Changes in large-scale vegetation structure triggered by processes such as deforestation, wildfires, and tree die-off alter surface structure, energy balance, and associated albedo-all critical for land surface models. Characterizing these properties usually requires long-term data, precluding characterization of rapid vegetation changes such as those increasingly occurring in the Anthropocene. Consequently, the characterization of rapid events is limited and only possible in a few specific areas. We use a campaign approach to characterize surface properties associated with vegetation structure. In our approach, a profiling LiDAR and hemispherical image analyses quantify vegetation structure and a portable mast instrumented with a net radiometer, wind-humidity-temperature stations in a vertical profile, and soil temperature-heat flux characterize surface properties. We illustrate the application of our approach in two forest types (boreal and semiarid) with disturbance-induced tree loss. Our prototype characterizes major structural changes associated with tree loss, changes in vertical wind profiles, surface roughness energy balance partitioning, a proxy for NDVI (Normalized Differential Vegetation Index), and albedo. Multi-day albedo estimates, which differed between control and disturbed areas, were similar to tower-based multiyear characterizations, highlighting the utility and potential of the campaign approach. Our prototype provides general characterization of surface and boundary-layer properties relevant for land surface models, strategically enabling preliminary characterization of rapid vegetation disturbance events.
107

How might we create a more realistic ECG Training?

Siebert, Jost January 2016 (has links)
Electrocardiography (ECG or EKG) is the process of recording the electrical activity of the heart over a period of time using electrodes placed on a patient’s body. These electrodes detect the tiny electrical changes on the skin that arise from the heart muscle depolarizing during each heartbeat. [1] It is necessary for the diagnosis and prompt initiation of therapy in patients with acute coronary syndromes (ACS) and is the most accurate means of diagnosing conduction disturbances and arrhythmias. [2]ECG is an irreplaceable diagnostic method in clinical practice. It offers great diagnostic value at minimal costs while being a relatively quick, painless and noninvasive process. The quality of the resulting graph is depending on the accurate placement of the electrodes on the patients' body and that the patient lies absolutely still to avoid any muscle contractions which may lead to distortions of the graph.The interpretation of ECGs is a highly complex topic which requires lots of training and experience. Although there has been plenty of research on the topic of automated interpretation and pattern recognition of ECGs by computer algorithms and neural networks, a reliable interpretation of complex ECGs cannot be guaranteed as of today. While the trend seems to favor automated ECG interpretation, a clear prediction when these technologies have saturated the market cannot be given. One reason for this, similar to autonomous vehicles, is the issue of where liability can be found when an incorrect diagnosis leads to harming of a patient. For the foreseeable future we will most likely rely on the skill and experience of humans to interpret ECGs. [1] https://en.wikipedia.org/wiki/Electrocardiography [2] The British Journal of Primary Care Nursing: Taking an ECG: Getting the best possible recording
108

Ecology, tourism and management of harbour seals (Phoca vitulina)

Granquist, Sandra M. January 2016 (has links)
In cases where human and wildlife are co-using the same geographical areas and resources, management issues often get complex and stakeholder conflicts are common. The Icelandic harbour seal (Phoca vitulina) population is rapidly decreasing, but direct culling of seals still occurs. At the same time seals are becoming an important resource due to increased interest in wildlife watching. Despite the complicated management situation, the Icelandic harbour seal population is one of the least studied pinniped populations in the world. Mapping the typical haul-out pattern is an important foundation for further studies. In paper I haul-out behaviour of harbour seals was investigated and a seasonal haul-out pattern was detected with the maximum number of seals hauling out during summer. A bimodal distribution curve was found during the summer time, suggesting that pupping period occurs in late May to early June, while moulting occurs in late July to early August. Tidal state, air-temperature and wind-speed affected the haul-out boots. Today, the main reason for culling harbour seals in Iceland is to reduce harbour seal predation on salmonids, despite limited knowledge on the effect of seal predation on salmonid populations and salmon angling. The diet of harbour seals that haul out in the estuary area of Bjargós and Ósar in NW-Iceland was therefore investigated using hard-part (paper II) and DNA metabarcoding analysis (paper III). Both methods showed that the main prey species were sand eels, flatfishes, gadoids, herring and capelin, while salmonids were not an important prey in this area. Based on these results, culling of harbour seals in the area is not likely to have a positive effect on salmonid angling. These results have crucial management implications, especially in the light of the severe decline in the Icelandic harbour seal population. Potential effects of seal watching tourism on the harbour seal population must also be considered in management plans. In paper IV, we investigated the effects of land based seal watching on seal behaviour and found that spatial distribution and vigilance was affected by tourists. Calm tourists behaviour had less effect, meaning that disturbance could be reduced if tourist behaviour is modified. In paper V, this line of investigation was followed by analysing knowledge transfer from academia to the tourist industry and a model was presented where a synergy effect of working interdisciplinary is hypothesised. Finally, in paper VI, the effect of signage on tourist behaviour was studied. Empirical testing showed that teleological information is more effective than ontological in terms of modifying general tourist behaviour. In this thesis, I present new knowledge on behaviour and diet of harbour seals, as well as new empirical findings on tourist behaviour in wildlife tourism settings. Further I explore interdisciplinary management approaches for seal watching tourism. The findings presented in this thesis have an important value within academic research in environmental-, life- and social sciences and the knowledge can be applied in several areas of harbour seal management in Iceland and elsewhere. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 6: Manuscript.</p>
109

Stress response of boreal woodland caribou, moose, and wolves to disturbance in eastern Manitoba

Ewacha, Michelle 15 September 2016 (has links)
Disturbance can provoke a chronic (long-term) stress response in wildlife, and can contribute to population declines. I examined the stress response of boreal woodland caribou, moose, and wolves to disturbance in eastern Manitoba by measuring cortisol concentrations in hair. Caribou cortisol concentrations were greatest for the three most southern populations, and increased with decreasing home range size. Intermediate logging (6-21 years) provided the best explanation for individual variation in caribou cortisol concentrations. Disturbance did not affect moose cortisol concentrations, but cortisol concentrations were higher in moose killed by wolves than moose collected by humans, suggesting that chronic stress in moose is linked to poor body condition and increased vulnerability to wolf predation. Wolf cortisol concentrations increased in 2012 and 2013 compared to 2011 following increased harvest pressure, and were higher in females. However, neither winter severity nor variation in wolf diet affected wolf cortisol concentrations. / October 2016
110

Microenvironment but not seed bank distribution affects plant competition on Richardson’s ground squirrel (Urocitellus richardsonii) mounds in Manitoba pastureland

Newediuk, Levi 01 November 2016 (has links)
Microsite disturbances – including mounds created by burrowing mammals – increase local plant community diversity by supporting unique species assemblages. I investigated whether Richardson’s ground squirrel (Urocitellus richardsonii) mounds support unique plant assemblages within five Manitoba prairie pastures, and explored the factors contributing to the plant assemblages documented. Richardson’s ground squirrel mounds supported unique species assemblages relative to bare-ground disturbances with removal of vegetation but no soil disturbance. These detectable shifts in plant community structure on mounds appear to be attributable to mound-specific environmental conditions responsible for delaying vegetative recolonization and facilitating establishment of early-succession species. In contrast, seed bank distribution did not appear to influence species assemblages on mounds. Further investigation into site-specific changes in species distribution on Richardson’s ground squirrel mounds is needed to appreciate the role of these burrowing mammals in pastureland communities. / February 2017

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