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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.
601

The impact of the counseling environment on clients' desire to affiliate and level of state anxiety

Fink, Samuel H. January 1980 (has links)
The purpose of this study was to extend the theoretical approach to environmental psychology set forth by Mehrabian and Russell to outpatient mental health treatment settings. Mehrabian and Russell have proposed that the effects of the physical environment on behavior are mediated by emotional responses to that environment, and that these emotional responses can be summarized by three independent and bipolar dimensions: pleasure-displeasure, arousal-non-arousal, and dominance-submissiveness.This project was accomplished in two parts. The primary emotional reactions elicited by a variety of six mental health clinics were assessed. Then, an attempt was made to determine whether physical settings as judged on the three emotional dimensions influenced clients' desire to affiliate with a counselor or therapist and their level of state anxiety. It was hypothesized that, as compared to clients in less pleasant counseling settings, those inmore pleasant counseling settings would express a greater desire to affiliate with a counselor, and would report less state anxiety.Raters utilized for evaluating the six mental health clinic environments consisted of 30 undergraduate and graduate students at Ball State University. While imagining themselves as individuals seeking counseling services for the first time, the raters first observed six slides of each of the mental health clinics, depicting the entrance, reception area, and waiting room. After viewing each set of slides, the raters responded to the emotional response scales developed by Mehrabian and Russell.The environmental ratings were compared using the Newman-Keuls method of multiple comparisons, which revealed that raters perceived a clear difference in the pleasantness-eliciting qualities of the six sites. Two sites were placed in the most pleasant grouping, three were placedin the neutrally pleasant range, and one was clearly viewed as unpleasant. Generally high item-dimension correlations provided support for the reliability of the scales.Subjects utilized in this study consisted of 40 client applicants in five of the six previously rated clinics. Efforts to obtain a larger sample were hindered by a low rate of intake in some clinics and possible reluctance by some personnel to impose additional "paperwork" on new clients. It was not possible to obtain any sample from the clinic evaluated as least pleasant. Prior to their initial interview with a therapist, subjects responded to Mehrabian and Russell's two question desire to affiliate questionnaire and the State-Trait Anxiety Inventory (STAI). Overall, subjects expressed a moderate level of desire to affiliate and a high level of state anxiety.Data were analyzed by two multiple, linear regression equations, utilizing desire to affiliate and state anxiety as criterion variables, and using pleasure, arousal, 'dominance, sex, and age as predictor variables. The results failed to support the hypotheses. Only one of the predictor variables was found to explain a significant amount of the variance on desire to affiliate. Client sex accounted for 17.1% of the variance (p <.05), indicating that male clients in this study expressed a greater desire to affiliate with a counselor compared to female clients. It was speculated that because fewer men were seeking psychological services, they may have been a small self-selected group who were more highly prepared than others to share their concerns with a therapist. None of the predictor variables were found to account for a significant amount of the variance on state anxiety.The interpretability of the results was hampered by the relatively small sample size, and by the non-inclusion of data from a site clearly rated as unpleasant. Also, since most previous research on environmental effects was not done in mental health treatment settings, it is conceivable that a population suffering from emotional or psychological problems may actually react differently to environmental conditions compared to the general populace.
602

Relationship of personal factors and perceived built environmental factors to walking behaviour of community-dwelling middle-aged and older adults

Chen, Yijie (Jennifer) 03 April 2013 (has links)
The purpose of this study was to investigate the relationship between personal factors and perceived built environmental factors and walking behaviour among middle-aged and older adults. The sample consisted of 647 people aged 45 years and above. Walking behaviour was assessed using pedometers. Decreased walking was significantly associated with increased age (r=-0.366, p<0.001). Education level (F=4.13, p=0.016) and self-rated health status (t=6.07, p<0.001) were positively associated with walking. When considering the effect of age, education level was no longer associated with walking. Better perception of general safety (F=3.105, p=0.005) and fewer safety concerns (F=7.531, p=0.001) were positively associated with walking. Age and self-rated health status jointly contributed to the walking behaviour (p<0.001), explaining 16.2% of the variance. These findings may suggest future neighbourhood interventions for age-friendly communities in Winnipeg, and help to accommodate changes through addressing perceived neighbourhood safety concerns and facilitating increased physical activity among middle-aged and older adults.
603

Design of a neurosurgical manipulator for applications in MRI environment

Banthia, Vikram 06 April 2011 (has links)
This thesis presents the design of a personal computer (PC) based needle insertion robotic manipulator for biopsy. The robot was designed and built using materials available in the research laboratory. The robot is intended primarily for use inside the confined area of a cylindrical magnetic resonance (MR) scanner. Selection of the robot geometry and novel locations for drive actuators allowed placement of actuators outside the MRI bore. The robot is modeled using Denavit-Hartenberg transformations. Custom developed software control is developed to test the functional aspects of the robot. The robot performs to the tolerance required for the stated clinical application. This thesis addresses only proof of concept chosen for the manipulator design and is not ready for any clinical trials. The work also addresses MRI compatible and safety issues and recommends appropriate materials for future development. Traditionally, neurosurgical navigation has relied on preoperative images and the assumption that anatomical structures of interest remain in the same position with respect to each other and the fiducial markers used for registration. However, during surgery, tissue deformation and shift disrupt the spatial relation between the patient and the preoperative image volumes. This results in localization errors. Developing a manipulator that works inside an imaging machine guided by real time images is expected to minimize the problem of “tissue shift” during the surgery.
604

Uranium in the environment: a characterization and comparison of uranium mobility in ancient and modern sediments

Bergen, Laura January 2012 (has links)
The behavior of U in near surface sedimentary environments has changed throughout geologic time. There is a marked shift in U (IV) mineral stability and deposit style at approximately 2200 Ma due to changes in the concentration of O in the atmosphere. For example, prior to 2200 Ma, fluvial U deposits could form and U(IV) were stable in surface and near-surface environments. In modern, anthropogenic sedimentary systems such as U tailings, U (IV) minerals are not stable and readily oxidize to U (VI) minerals. In addition, U is much more mobile in modern sediments relative sediments that were deposited prior to 2200 Ma.
605

Transcendental unity: mana-mediations in Māori lore.

Ruta, Kimberley 30 August 2011 (has links)
This analysis uses the term mana as a lens to interrogate a regionally diverse range of Māori lore texts. It will be seen that categories of human-nature, natural-supernatural are often permeable in Māori lore because of the agency provided by mana. This permeability is transcendental unity which destabilizes the notion that humans are fully distinct from their environment. Transcendental unity is expressed in Māori lore through changes in states of being or planes of existence, biological-environmental metaphoric equivalences, and metaphysical spheres of reciprocal influence. I argue relations between humans and the non-human environment involve genealogical ties, are mediated by mana, and suggest a transcendental form of unity characterized by common essence and characteristics. / Graduate
606

Performance analysis of cognitive transmission in multiple cell environment

Zhang, Dong 24 August 2012 (has links)
This thesis conducts a performance analysis of cognitive transmission in a multiple- cell environment. Most of the cognitive radio (CR)-related research has focused on scenarios where a secondary system operates in the presence of a single primary com- munication system. In this work, we extend the study of a single-cell scenario to a more practical scenario where the secondary system is subjected to two independent primary users (PU). In particular, we investigate the performance of a secondary system operating in an interweaving fashion to explore the spectrum of opportuni- ties. Under the assumption of the Poison traffic model for PU activities, we apply the Markov chain model to first determine the system parameters for combined PUs activities, and then characterize the dynamics of the spectrum opportunities for a secondary user (SU) for both single- and multiple-channel access. To fully inves- tigate the proposed system, we also consider some possible drawbacks and provide corresponding solutions in the extension section. We derive the exact mathematical expressions for the performance metrics, in- cluding average waiting time and average service time of the SU transmission. To enrich the performance analysis, other performance metrics, such as average through- put and collision frequency/ratio are also presented. Through selected numerical examples, we examine the effect of different operation parameters on the SU system performance. We believe that those analytical results can help predict which types of SU applications can be supported under certain practical PU activities. / Graduate
607

The management of coastal erosion and flooding in England and Wales

Pettit, S. J. January 1993 (has links)
No description available.
608

The origins and occurrence of estrogenic A-ring aromatic steroids in U.K. sewage treatment works effluents

Niven, Stewart James January 1999 (has links)
There is worldwide concern over the possible estrogenic effects of organic chemicals on a variety of wildlife and indeed on humankind. In the U.K., estrogenic compounds in sewage treatment works (STW) effluents have been implicated in causing the increases in egg yolk protein production observed in caged male trout and other fish species. At the initiation of the present study, few of the estrogenic compounds in STW effiuents had been recognised, although circumstantial evidence suggested that steroidal hormones were primary candidates. Cholesterol is abundant in STW effluents and is the precursor of all steroidal hormones biosynthesised in mammalian systems. Thus, the aim of the present study was to examine the hypothesis that cholesterol might undergo A-ring aromatisation, during sewage treatment, producing estrone and 17β-estradiol via, intermediates such as l9-norcholest-l,3,5(10)-trien-3-ol (NCT). To study this hypothesis NCT was first synthesised via a known route and several of its chromatographic and mass spectral properties established for the first time. NCT itself was found to possess some estrogenic potential determined using an established assay but this was rather weak compared to 17β-estradiol - about 200,000 times less active at the minimum concentration needed to invoke a response. NCT also proved to be a much more hydrophobic compound than, for example, 17β-estradiol with a computed log octanol-water partition coefficient (Kow) of over 9 compared with a log Kow of about 4 for l7β-estradiol. The established analytical properties of NCT were then used to investigate possible NCT formation in sewage. Radiolabelled 14C-cholesterol was incubated aerobically and anaerobically in Semi-Continuous Aaivated Sludge (SCAS), Die Away (DA) or simple stand alone STW simulation vessels. The products of incubation in both aqueous and solid fractions were examined by radio-high performance liquid chromatography (r-HPLC), radio-thin layer chromatography (r-TLC) and radio-gas chromatography (r-GC). Aerobic studies showed that side chain cleavage and A-ring rupture of cholesterol occurred rapidly (~25 % of added activity within 24 hrs) as measured by 14C02 evolution. Gaseous evolution was not monitored from the anaerobic experiments. Most remaining activity was associated with the solids fractions in all experiments. In the aqueous experiments both SCAS and DA systems, r-HPLC revealed rapid production of polar products which were not identified further. r-HPLC also revealed non-polar components of which choIest-3,5-diene, an unknown cholestadiene, a cholestadienol (other than 5,7-dienol), cholest-4-en-3-one and possibly NCT were identified by r-GC in the products of DA experiments. Whilst r-HPLC and r-TLC also revealed several products of anaerobic digestion of cholesterol, no compounds were detected by r-GC. STW effluents from two wastewater plants in the North London area were monitored over 7 months for A-ring steroids and other suspected estrogenic chemicals. Both effluents had previously proved estrogenic to caged fish. Liquid and SPM samples were taken, extracted and analysed by GC-MS. The two main estrogens, l7β-estradiol and estrone were identified from all liquid samples but not in SPM extracts. Generally the concentration of estrone (maximum ca 3 ng Lˉ¹) was significantly higher than that for 17β-estradiol (maximum 1 ng fˉ¹). The third natural estrogen, l6a,l7β-estriol, was identified in all Harpenden effluent samples analysed up to a concentration ca 0.5 ng Lˉ¹. However, estriol was not found in Deephams effluent extracts. The phytoestrogen, daidzein, found in soya based products was intermittently found in aqueous effluents samples from both sites >1 ng Lˉ¹. SPM made up <0.001 % of the effluent. Extracts showed that there was a high percentage of steroidal based material with coprostanol>cholesterol=β-sitosterol>>stigmasterol. NCT was twice identified from SPM taken from Deephams with a concentration of 39 and 136 ng 1ˉ¹ but <LOD in Harpenden SPM extracts. In conclusion this study showed that formation of NCT from cholesterol in STW treatment under conditions monitored herein is not a major process. However, estrone, 17β-estradiol and 16a, 17β-estriol are relatively abundant and widespread components of the STW effluents tested. The origins of the components undoubtedly include direct inputs from female urine and faeces but other metabolic sources should not be entirely ruled out.
609

The study of the dissolved nitrogen containing macromolecules in the marine environment

Chapman, Jasmin January 1988 (has links)
No description available.
610

Urban public spaces : a study of the relation between spatial configuration and use patterns

Arruda Campos, Maria Beatriz Mattei de January 2000 (has links)
This thesis sets out to investigate the key spatial properties that make for successful urban public spaces; specifically, which spatial properties lead to high levels of static occupation and which spatial properties affect the patterns of static distribution of people inside public spaces. This is a subject which has long attracted attention among urban designers, amongst whom there is a general consensus that well-designed urban places are lively, busy and vibrant, and that these properties are somehow, albeit unclearly, connected with design variables. However, in contrast to designers who often have treated public spaces as discrete spatial entities emphasising on localised spatial properties such as enclosure or quality and quantity of decorative elements, it is suggested that not enough has been done to understand the relationship between patterns of spatial use and global, relational features of public places. This research is therefore based on two propositions. The first is that the way public spaces are used is influenced by the permeable and visual connections that hold between the specific space under investigation and the configuration of the urban fabric where they are embedded and levels of pedestrian movement associated with it. The second is that these key spatial properties which are identified in the performance of public spaces can be found in traditional historical urban squares. The morphological analysis of 30 traditional historical urban squares of European towns and 12 public spaces in the City of London, which compose the main case study for providing quantifiable evidence on levels and distribution of static people, revealed three major issues. Firstly, the level of static people inside public spaces is directly related to levels of pedestrian movement across the public space, quantified through the 'strategic value', this being numerically defined as the sum of the integration values, or the degree of accessibility, of lines of sight and movement which pass through the body of the space. Secondly, the distribution of static people inside public spaces is inversely related to the level of visual connectivity between the internal areas of the public space and the surrounding grid, quantified by the degree of 'coverage density'. Thirdly, only the spatial properties which have been identified to be common to both samples showed to be related with the patterns of spatial use of public spaces. Consequently, these findings shape a new approach to the issue of patterns of spatial use of public spaces, based on the global understanding of the dynamics of the urban grid and the visual and permeability connections between public space and the urban environment.

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