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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.
391

Restricted Verb Phrase Collocations in Standard and Learner Malaysian English

Abd Halim, Hasliza January 2014 (has links)
The English used in Malaysia is one of the varieties of New Englishes and this variety has emerged due to the spread of English around the world (Platt, et al., 1983; Pillai, 2006). In the case of Malaysia, Malay is the national language and standard English exists to be the language of an elite (Bao, 2006), also as a language of interaction. Over years of playing its various roles as a language of interaction, there has emerged a variety of English that is distinctively Malaysian (Asmah, 1992). Baskaran (2002) points out that English is now adopted and adapted in the linguistic ecology of Malaysia, and all Malaysians should be proud of it with all its local ‘nuances and innuendos’. Malaysian English today is ‘a rich tapestry of a typical transplanted variety of English’. Malaysian English (ME) is one of the new varieties of English, with some distinct features include the localized vocabulary, pronunciation, grammar as well as pragmatic features (Pillai, 2006; Pillai and Fauziah, 2006, p.39). The present study has embarked on a specialised study of vocabulary. In particular, it examined the English collocations produced by non-native speaker English users in Malaysia. The study provided insight into the nature of the internal norms of English used in Malaysia to see how these English restricted collocations being used by this group of learners. The investigation focused on the learners’ productive knowledge of Verb-Noun collocations of their written English with the impact of exposure and frequency. Nesselhauf (2003) has the opinion that verb-noun combinations are the most frequently mistaken so they should perceive particular attention of learners. Investigating collocation in English language learning is paramount as such study may inform us on the use of restricted collocations in English language teaching and learning in Malaysian context. The findings in Chapter 4 and 5 suggest that the frequency of the cloze verb does have an effect as predicted by Kuiper, Columbus and Schmitt (2009). This is so because frequency is a measure of likely exposure. The more frequent an item is in corpora, the more likely a learner is to be exposed to it. What is needed is a much more nuanced notion of exposure. The findings in Chapter 6 proves that the malformed collocations make sense could be a way of making the World English perspective relevant after all. A new testing approach is proposed; semantic plausibility metric, which is used as a tool for this study, can be useful used as a measure of vocabulary acquisition as well as looking at learners’ test taking strategies. The findings of the present research on Malaysian English collocations contribute new knowledge to the existing understanding and literature on the acquisition of collocations.
392

Lead exposure in indigenous children of the Peruvian Amazon : seeking the hidden source,venturing into participatory research

Anticona Huaynate, Cynthia January 2012 (has links)
Introduction. In 2006, a Peruvian environmental agency reported the presence of elevated blood lead levels (BLLs) in indigenous communities of the Corrientes river basin. This is a territory in the Peruvian Amazon where oil activity has been associated with serious environmental effects, with impact on an ongoing social conflict. This PhD project aimed to determine the lead sources, risk factors and pathways in children of these communities and to suggest control and prevention strategies. Given the arguments attributing the lead source to the oil activity pollution, the second objective was to clarify any potential connection between the two. This project was conducted by a collaborative research partnership with the regional health authorities and the community-based organization. The third objective was to characterize the challenges, facilitating factors and the lessons learned from the research process. Methods. Two epidemiological studies were conducted. Study I (2009) was carried out in three communities and study II (2010) in six communities with different levels of exposure to oil activity. The participants were children 0–17 years old. Data collection included: determination of BLLs, hemoglobin levels and anthropometric indicators, a risk factor questionnaire, an environmental assessment and a risk map. Data analysis included univariate, bivariate and multivariate logistic regression. Data for the third objective came from field notes, documents, interviews and a process of collective reflection. Results. Study I (n= 221) found no significant difference in the geometric mean(GM) BLLs between the communities exposed and not exposed to oil activity. Older age and being a boy were found as risk factors for BLLs ≥ 10 μg/dL. In study II (n= 346), age stratified logistic regression models indicated that children 0–3 years whose mothers had BLLs ≥ 10 μg/dL, children 0–6 years who played with pieces of lead and children 7–17 years who fished 3 times or more per weekor chewed pieces of lead to manufacture fishing sinkers had a significant increased risk of having BLLs ≥ 10 μg/dL. Children who lived in communities near oil battery facilities also had a significant increased risk of having BLLs ≥ 10 μg/dL. In both studies, environmental samples showed lead concentrations below reference levels. The challenges and facilitating factors identified focused on five interrelated themes: i) mutual trust, ii) multiple agendas, iii) equal participation, iv) competing research paradigms and v) complex and unexpected findings. Conclusions. Metal lead appeared to be the main source of exposure. Playing with pieces of lead and chewing pieces of lead to construct fishing sinkers appeared to be pathways of exposure for children aged 0–6 years and 7–17 years, respectively. Mothers’ BLLs > 10 μg/dL was a risk factor for BLLs > 10 μg/dL in children aged 0–3 years. Living in a community with high exposure to oil activity was a risk factor for BLLs > 10 μg/dL. The identified connection with oil activity was the proximity of communities to oil battery facilities and thus greater access to lead from cables and other industrial waste. Despite the numerous challenges, participatory research appears to be the most appropriate approach for this type of context. The study findings led us to recommend:i) a comprehensive community-based lead control and prevention plan,ii) the introduction of substitute non-harmful material(s) for fishing sinkers and iii) secure containment of the oil company’s waste deposits. / Introducción. En el 2006, una agencia ambiental del Perú informó de la presenciade niveles elevados de plomo sanguíneo en las comunidades indígenas dela cuenca del río Corrientes. Este es un territorio en la Amazonía peruana, dondela actividad petrolera ha sido asociada con graves efectos ambientales, originandoun continuo conflicto social.Este proyecto de tesis doctoral tuvo como objetivo determinar las fuentes, factoresde riesgo y vías de exposición de plomo en niños de estas comunidades paraproponer estrategias de control y prevención. Teniendo en cuenta previos argumentosque relacionaban la exposición de plomo con la contaminación por laactividad petrolera, el segundo objetivo fue esclarecer cualquier conexión entreambos. Este proyecto se condujo con la participación de miembros de la DirecciónRegional de Salud de Loreto (DIRESA Loreto) y de la organización indígenaFECONACO. El tercer objetivo fue caracterizar los desafíos, las oportunidades ylos aprendizajes del proceso participativo.Métodos. Se condujeron dos estudios epidemiológicos. El estudio I (2009) sedesarrolló en tres comunidades y el estudio II (2010) en seis comunidades condiferentes niveles de exposición a la actividad petrolera. Los participantesfueron niños de 0–17 años. La recolección de datos incluyó: determinación deplomo sanguíneo, de niveles de hemoglobina y de indicadores antropométricos,un cuestionario de factores de riesgo, una evaluación ambiental y un mapa deriesgo. El análisis de datos incluyó análisis univariado, bivariado y multivariadode regresión logística. Para el tercer objetivo, los datos provinieron de notas decampo, documentos oficiales, entrevistas informales y un proceso de reflexióncolectiva.Resultados. En el estudio I (n = 221) no se encontró diferencia estadísticamentesignificativa entre las medias geométricas de los niveles de plomo sanguíneo delas comunidades expuestas y no expuestas a la actividad petrolera. Los niños degénero masculino y los del grupo etario de mayor edad tuvieron un riesgo significativamentemayor a presentar niveles de plomo sanguíneo > 10 μg/dL. Enel estudio II (n = 346), los modelos estratificados por edad indicaron que losniños de 0–3 años cuyas madres tenían niveles de plomo > 10 μg/dL, los niñosde 0–6 años que jugaban con piezas de plomo y los niños de 7–17 años que pescaban3 veces o más por semana o masticaban piezas de plomo para fabricarpesas de pescar tenían un riesgo significativamente mayor de presentar nivelesde plomo sanguíneo > 10 μg/dL. Los niños que vivían en comunidades cercanasa las baterías de petróleo también tuvieron un riesgo significativamente mayora presentar plomo sanguíneo > 10 μg/dL. Las muestras ambientales en ambosestudios mostraron concentraciones de plomo por debajo de los niveles de referencia.En cuanto al proceso de investigación, los desafíos y oportunidades másimportantes se centraron en cinco temas interrelacionados: i) la confianza mutua,ii) múltiples agendas, iii) participación equitativa, iv) competencia de paradigmasen la investigación y v) diseminación de resultados complejos e inesperados.Conclusiones. La fuente de exposición principal sería el plomo metálico. Jugarcon piezas de piezas de plomo y masticar piezas de plomo para la construcciónde pesas de pescar serían vías de exposición para los niños de 0–6 años y 7–17años, respectivamente. Niveles de plomo sanguíneo > 10 μg/dL en las madressería un factor de riesgo para presentar niveles de plomo sanguíneo > 10 μg/dLen niños de 0–3 años. Vivir en una comunidad con alta exposición a la actividadpetrolera sería también un factor de riesgo para presentar niveles de plomo sanguíneo> 10 μg/dL. La conexión con la actividad petrolera parece estar en laproximidad de las comunidades a las baterías del petróleo y por ende, el mayoracceso al plomo proveniente de cables y otros residuos industriales.A pesar de los varios desafíos, la investigación participativa parece ser el enfoquemás apropiado para este tipo de contextos. Los hallazgos nos llevaron a recomendar:i) un programa comunitario de control y prevención de plomo, ii) laintroducción de pesas de pescar de materiales seguros, alternativos al plomo yiii) el control de la disposición de residuos de la actividad petrolera.
393

Effects of Repeated Cue Exposure on Cannabis Craving

Fogel, Jessica S 01 January 2015 (has links)
Craving is a key element of the cannabis withdrawal syndrome that has been associated with continued use and relapse. Although cue-induced cannabis craving has been established in single laboratory sessions, procedures to sustain craving over multiple sessions are needed. The purpose of the present study was to determine if cue-induced craving responses could be elicited in the same subjects across multiple sessions. It was hypothesized that exposure to cannabis cues would produce more robust craving responses than exposure to neutral cues and that elicited craving responses will be sustained across multiple cue exposures. Five experimental cue exposure sessions (1 neutral and 4 cannabis) were conducted. Craving was assessed with the Marijuana Craving Questionnaire (MCQ) Short Form, Visual Analog Scale (VAS), Subject-Rated Physiological Questionnaire, blood pressure, and heart rate. Results revealed significant effects of initial cannabis cue exposure on VAS craving responses and Subject-Rated Physiological measures relative to the neutral cue exposure condition. No significant differences were found on MCQ composite scores or physiological measures. Craving responses following initial cannabis cue exposure were not maintained across sessions. There is a need for a better understanding of the factors that contribute to continued drug use despite quit attempts.
394

Wisselkoersblootstelling van multinasionale ondernemings in Suid-Afrika / Z. Blignaut

Blignaut, Zelda January 2004 (has links)
Multinational enterprises (MNEs) are central drivers behind neo-liberal globalisation. These enterprises are usually centred in developed countries, with competitive operations in developing countries. The literature on MNEs and foreign direct investment usually focus on the motivation for investment, decisions on expansion, the structure of ownership of investment, the mode of entry, and the perception of risk. Fluctuation in the exchange rate is a source of uncertainty that affects MNEs' and other enterprises' market values. Enterprises' exposure to changes in the exchange rate has increased with the adoption of floating exchange rates and more intensive involvement in international trade. The conventional belief is that competition in the export market is positively related to a depreciation of the exchange rate, which will in turn be advantageous to the stock market, while the opposite is true for an appreciation of the exchange rate. If the contribution of import or intermediate imported inputs to the final production were quite large, an appreciation of the exchange rate will have a positive effect on input costs and the stock market. This study investigates the exchange rate exposure of multinational enterprises in South Africa to the bilateral exchange rate of the rand against the US dollar and the nominal effective exchange rate of the rand. It presents evidence on the direction and magnitude of currency exposure. From the empirical results presented in this study it can be concluded that the majority of MNEs are not significantly exposed to either one of the exchange rate changes. It has also been found that the majority of enterprises lose market value when their local currency depreciate against the US dollar, while the majority of South African enterprises are positively related to changes in the nominal effective exchange rate of the rand. MNEs that are not significantly exposed to changes in exchange rates could be subject to three possibilities. (1) The most obvious reason is that enterprises are not exposed to changes in the exchange rate. Enterprises in liberated (or •open") countries are more exposed to exchange rate movements as opposed to those in closed countries, such as the USA. (2) Enterprises could be engaged in on and off balance sheet hedging activities, which would reduce exchange rate exposures. (3) The methodology used in a study does not present the correct exposure results. / Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2005.
395

Exposure of Tanzanian gold mine refinery workers to hydrogen cyanide / K. Linde

Linde, Karlien January 2008 (has links)
Hydrogen cyanide gas (HCN{g)) is formed during the process of extracting gold from ore and may pose a risk to the health of the workers at the gold refinery (Mill/plant), especially the risk of detrimental effects on the central nervous system and the cardiovascular system. The measurement of the personal airborne HCN(g) exposure of a worker using sorbent tubes, provides the concentration of the chemical that the worker breaths in. The measurement of the urinary thiocyanate (SCN~) concentration provides the total HCN exposure experience by the worker through all possible routes of exposure. The study's aim was to determine if the workers were exposed to HCN(g) concentrations that was higher than the occupational exposure limit (OEL) , which would mean that the workers are exposed to excessive and possibly harmful levels of HCN. The monitored workers were divided into three homogenous exposure groups or HEGs, according to the their potential level of exposure. The results were compared between the three HEGs and between three work description groups, namely the Mill/plant workers, SGS laboratory assistants and members of the environmental department. The study found that all the workers were exposed to personal airborne HCN(9) concentrations below the OEL. A statistical significant difference was found the personal airborne exposure experienced by the three HEGs and between the Mill/plant workers and the members of the environmental department. No statistical significant difference was found between the urinary SCN" concentration found in the three HEGs or the between the three work description groups. Confounding factors such as smoking, the consumption of cassava, the exposure to fire smoke and the amount of time worked at the mine did not influence the urinary SCN~ concentration. The implementation of a biological monitoring program would enable the identification of any worker that is exposed to excessive levels of HCN. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2009.
396

Exposure of Tanzanian gold mine refinery workers to hydrogen cyanide / K. Linde

Linde, Karlien January 2008 (has links)
Hydrogen cyanide gas (HCN{g)) is formed during the process of extracting gold from ore and may pose a risk to the health of the workers at the gold refinery (Mill/plant), especially the risk of detrimental effects on the central nervous system and the cardiovascular system. The measurement of the personal airborne HCN(g) exposure of a worker using sorbent tubes, provides the concentration of the chemical that the worker breaths in. The measurement of the urinary thiocyanate (SCN~) concentration provides the total HCN exposure experience by the worker through all possible routes of exposure. The study's aim was to determine if the workers were exposed to HCN(g) concentrations that was higher than the occupational exposure limit (OEL) , which would mean that the workers are exposed to excessive and possibly harmful levels of HCN. The monitored workers were divided into three homogenous exposure groups or HEGs, according to the their potential level of exposure. The results were compared between the three HEGs and between three work description groups, namely the Mill/plant workers, SGS laboratory assistants and members of the environmental department. The study found that all the workers were exposed to personal airborne HCN(9) concentrations below the OEL. A statistical significant difference was found the personal airborne exposure experienced by the three HEGs and between the Mill/plant workers and the members of the environmental department. No statistical significant difference was found between the urinary SCN" concentration found in the three HEGs or the between the three work description groups. Confounding factors such as smoking, the consumption of cassava, the exposure to fire smoke and the amount of time worked at the mine did not influence the urinary SCN~ concentration. The implementation of a biological monitoring program would enable the identification of any worker that is exposed to excessive levels of HCN. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2009.
397

Corrosion Deterioration Characteristics of Structural Steel by Accelerated Exposure Test System under the Water

Itoh, Yoshito, Hirohata, Mikihito, Takemi, Junya, Yamachika, Yousuke 11 1900 (has links)
NACE international East Asia & Pacific Rim Area Conference & Expo 2013 (Kyoto Japan, November 19-21, 2013)
398

Fate and Transformation of Metal-(Oxide) Nanoparticles in Wastewater Treatment

Barton, Lauren Elizabeth January 2014 (has links)
<p>The study and application of materials possessing size dimensions in the nano scale range and, as a result, unique properties have led to the birth of a new field; nanotechnology. Scientists and engineers have discovered and are exploiting the novel physicochemical characteristics of nanoparticles (NPs) to enhance consumer products and technologies in ways superior to their bulk counterparts. Escalating production and use of NPs will unavoidably lead to release and exposure to environmental systems. This introduction of emerging potential contaminant NPs will provide new and interesting challenges for exposure and risk forecasting as well as environmental endurance.</p><p>The ultimate goal of this research is to develop a framework that incorporates experimental and computational efforts to assess and better understand the exposure of metal and metal-oxide NPs released to wastewater treatment plants (WWTPs) and further implications on land application units (LAUs) where biosolids can be applied. The foundation of the computational effort is comprised of Monte Carlo mass balance models that account for the unique processes affecting NP fate and transport through the different technical compartments of a WWTP and LAU. Functional assay and bioreactor experiments in environmental media were used to determine parameters capable of describing the critical processes that impact the fate of NPs in wastewater. </p><p>The results of this research indicate that a simplified, but still environmentally relevant nano-specific exposure assessment is possible through experimentation to parameterize adapted models. Black box modeling efforts, which have been shown in previous studies, show no disadvantage relative to discretization of technical compartments as long as all key transport and fate mechanisms are considered. The distribution coefficient (_), an experimentally determined, time-dependent parameter, can be used to predict the distribution of NPs between the liquid and solid phase in WWTPs. In addition, this parameter can be utilized a step further for the estimation of the more fundamental, time independent attachment efficiency between the NPs and the solids in wastewater. The NP core, size, and surface coating will influence the value of these parameters in addition to the background particle characteristics as the parameters are specific to the environmental system of study. For the metal and metal-oxide NPs studied, preferential overall association of approximately 90% or greater with the solid phase of wastewater was observed and predicted. </p><p>Furthermore, NP transformations including dissolution, redox reactions, and adsorption can potentially impact exposure. For example, experimental results showed that nano-CeO2 is reduced from Ce(IV) to Ce(III) when in contact with wastewater bacteria where Ce2S3 will likely govern the Ce(III) phase in biosolids. From the literature, similar transformations have been observed with Ag and ZnO NPs to Ag2S and ZnS. With respect to TiO2 NPs, studies indicated that due to high insolubility, these NPs would not undergo transformation in WWTPs. The distribution and transformation rate coefficients can then be used in fate models to predict the NP species exposed to aquatic and terrestrial systems and environmentally relevant concentrations released from WWTPs. </p><p>Upon completion of the WWTP model, the predicted concentrations of NPs and NP transformation byproducts released in effluent and biosolids were attainable. A simple mass balance model for NP fate in LAUs was then developed to use this output. Results indicate that NP loading on LAUs would be very low but that build up over time to steady state could result in mass concentrations on the order of the typical level for the background metal in soil. Transport processes of plant uptake and leaching were expected to greatly impact the solid phase concentration of the NPs remaining in the LAU, while rainfall did not impart a significant influence upon variation between low and high annual amounts. The significance of this research is the introduction of a method for NP exposure assessment in WWTPs and subsequently in LAUs. This work describes and quantifies the key processes that will impact Ag, TiO2, CeO2 and ZnO NP fate and transport, which can inform future studies, the modeling community and regulatory agencies.</p> / Dissertation
399

Investigating suggestibility in children with fetal alcohol spectrum disorder

MacSween, Jennifer 14 November 2012 (has links)
Interrogative suggestibility refers to the extent to which an individual internally accepts messages communicated during a formal questioning situation, as indicated by an external response. Research indicates low intelligence, poor memory and weak inhibitory control is associated with heightened suggestibility. Children with fetal alcohol spectrum disorder (FASD) may also display deficits in these key areas, indicating a potential vulnerability to suggestion. The present study compared levels of suggestibility among alcohol exposed and typical children. The findings indicate that children with FASD may be at heightened risk to suggestion following negative feedback or pressure. In addition, a large amount of the suggested material was elicited and internalized as truth by all children, dependent on question format. These findings have important consequences for future interrogative interactions with children with and without FASD, to ensure information is not presented and thus elicited in a suggestive manner. / Graduate
400

Katekol-O-Metyltransferas (COMT), tidigare övergrepp, gen-miljöinteraktion i förutsägelsen för våld / Catechol-o-Methyltransferase (COMT), Earlier Abuse, Gene-Environment Interaction in the Prediction of Violence

Andersson, Anneli January 2014 (has links)
Flera kandidatgener har föreslagits spela en roll i utvecklingen av antisociala beteenden i samband med miljöfaktorer. Syftet med den föreliggande studien var därmed att undersöka sambandet mellan genen Katekol-O-Metyltransferas (COMT) och våld; och om det fanns interaktioner mellan exponering för tidigare övergrepp och COMT i samband med senare våld. Data hämtades från en Svensk populationsbaserad studie baserad på 2500 20-24 åringar. Den aktuella studien fann att beroende på vilken variant av genen man besitter, kommer man att påverkas i olika grad av negativa miljöfaktorer såsom försummelse och sexuella övergrepp i samband med våld. / Several candidate genes have been suggested to play a role in the development of antisocial behavior in association with social and environmental factors. Therefore, the purpose of the present study was to investigate the relationship between the gene Catechol-O-Methyltransferase (COMT) and violence; and to examine whether there were interactions between earlier abuse and COMT in the association of violence. Data were drawn from a Swedish population-based study including 2,500 20-24 year olds. The present study found that depending on which variant of the gene one possess, one will be affected to different degree of adverse environmental factors in association with violence.

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