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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.
131

A Survey of Attitudes, Materials and Techniques used in Endodonic Treatment by South African Dentists

Naidoo, Lushen Manickum 14 November 2006 (has links)
Student Number : 9703077F - MSc research report - School of Oral Health Sciences - Faculty of Health Sciences / Guidelines for endodontic procedures and practice have been described, but in South Africa there is no information on the adherence of practitioners to such guidelines. The aim of this study was to provide this information by administering a questionnaire to 1367 members of the South African Dental Association. Although the response rate was poor, 111 replies could be used. The majority of these respondents had more than 5 years experience. Half used a rubber dam, which is favourable relative to the global practice of endodontics. The majority use engine-driven instruments for canal preparation and all the respondents use radiographs. Lateral condensation and gutta percha were the preferred choices for canal obturation. Single-visit treatment was performed with varying frequency. The conclusion of this study is that South African dentists do adhere to most international and current standards. However, there is a need to develop quality assurance guidelines for endodontic treatment for South Africa, and which can also be applicable for developing countries.
132

Understanding of factors associated with HIV prevalence in South Africa: analysis of the antenatal clinic survey data

Dikgale, Makgoka Freck 14 February 2011 (has links)
MSc (Med) Epidemiology and Biostatistics, Faculty of Health Sciences, University of the Witwatersrand / Research Project Title: HIV Prevalence and Factors Associated with HIV Infection in South Africa: Analysis of the Antenatal Clinic Survey Data. Background: In sub-Saharan Africa, the HIV epidemic is commonly monitored through the sentinel surveillance of pregnant women attending antenatal clinics (ANC), which provides important indications for planning and evaluating public-health interventions. Many of such surveillance systems in South Africa reported limited information on factors associated with HIV infection, even though the survey collected information related to a woman’s participation. This is likely to compromise the development of effective preventive programmes that are more focussed. To address this, the 2005 HIV (ANC) surveillance data was used with the objective of increasing the available information on the HIV epidemic in the country and identifying the socio-demographic factors associated with HIV infection in each province. Methodology: The data from the 2005 ANC survey was analysed in depth. The chi-square test was used to test bivariate associations for categorical associations of HIV infection and other associated factors. In addition a logistic regression model was used to explore the association of sociodemographic and other variables with HIV infection in each province. Results: The HIV prevalence reported in this study was similar to earlier reports released by the Department of Health in 2005. That is the overall HIV prevalence is 30.1% (29.5-30.8%) with KwaZulu Natal having the highest (39.1%, 37.5-40.1%) and Western Cape recorded the lowest HIV prevalence of 15.9% (14.1-17.4%).
133

Mamíferos não-voadores do Campus "Luiz de Queiroz", da Universidade de São Paulo, em Piracicaba, Estado de São Paulo. / Non-volant mammals of campus "Luiz de Queiroz", university of São Paulo, Piracicaba, SP, Brazil.

Gheler-Costa, Carla 25 April 2002 (has links)
A Floresta Atlântica, principalmente sua porção localizada no interior do Estado de São Paulo, encontra-se altamente fragmentada e seus remanescentes, em sua maioria, encontram-se envoltos por uma matriz essencialmente agrícola. Este estudo foi realizado no Campus "Luiz de Queiroz", Universidade de São Paulo, localizado no município de Piracicaba, Estado de São Paulo. O mesmo encontra-se inserido no perímetro urbano da cidade de Piracicaba, tendo como limite duas rodovias e o Rio Piracicaba. A paisagem da área de estudo caracteriza-se por um mosaico de pequena áreas florestais envoltas por áreas de pastagens, agricultura e florestamento com espécies exóticas. Os objetivos principais do presente estudo foram: levantamento de mamíferos não-voadores, em escala local, incluindo sua distribuição e abundância de acordo com o mosaico de ambientes resultantes do expressivo impacto causado pelo desenvolvimento humano na área. A coleta de pequenos mamíferos ocorreu durante nove meses, entre fevereiro e outubro de 2001, com um esforço de 7056 armadilhas/dia, tendo sido amostrados sete dos ambientes mais representativos do Campus(florestamento de Eucalyptus e Pinus, fragmento florestal nativo, várzea, plantio de seringueira, área de agricultura e área de pastagem). Para o registro de mamíferos de médio e grande portes foi construída uma trilha pelo Campus, que foi percorrida durante 12 meses, entre novembro de 2000 e outubro de 2001, no período da manhã e da tarde. Em todo o Campus foram registradas 16 espécies de mamíferos não-voadores, sendo dez de médio e grande portes e seis de pequeno porte, sendo a capivara (Hydrochaeris hydrochaeris) e o coati (Nasua nasua) as espécies mais abundantes. / The remaining portion of the Atlantic Forest within the State of Sao Paulo is highly fragmented and most of the remainders are wrapped up in an essentially agricultural mosaic. This study aims local surveying of non-flying mammals, including their distribution and relative abundance within the humanimpacted environments of Campus "Luiz de Queiroz", University of Sao Paulo, Piracicaba, SP, Brazil, an urbanized area bordered by two highways and the Piracicaba River. The landscape of the study area is characterized by a mosaic of small forest fragments surrounded by pastures, agriculture, and planted forests. Small mammals were captured from February to October, 2001, with an effort of 7056 traps.day -1 , sampling seven of the most representative environments of the Campus - planted Eucalyptus and Pinus forests, native forest fragments, meadow, rubber tree plantation, agriculture and pasture areas. Occurrence of medium and large frame mammals was recorded daily (morning and afternoon) from November of 2000 to October of 2001 along a trail set up to merge the studied environments. Sixteen species of non-flying mammals were recorded, ten of medium or big frames, and six of small frame. Capybara (Hydrochaeris hydrochaeris) and coati (Nasua nasua) were the most abundant species.
134

Uso do rbcL na identificação de espécies arbóreas da Floresta Estacional Semidecidual do estado de São Paulo / Identifying Semideciduos Seasonal Forest trees species of São Paulo state through rbcL

Colletta, Gabriel Dalla 11 May 2015 (has links)
O principal objetivo deste trabalho, foi avaliar a eficiêcia do rbcL na identificação das espécies arbóreas da Floresta Estacional Semidecidual do estado de São Paulo. Para isso, foi construído um banco de dados local de sequências derbcL de 149 espécies circunscritas em 64 famílias e realizado o teste de identificação. Os resultados de porcentagem de correta identificação variaram de 42,8 - 100% quando ordenados por score até 88 - 100% quando ordenados pela porcentagem de identidade, ficando evidente a importância na maneira de ordenar os resultados. Foi gerada também uma lista para as espécies arbóreas ocorrentes na Floresta Estacional Semidecidual no estado de São Paulo, que contou com 716 espécies incluídas em 80 famílias. / The main goal of this work was to evaluate the efficiency of the molecular marker rbcL in the identification of native tree species of Semideciduous Seasonal Forest, in São Paulo, Brazil. A local database of rbcL sequences from 149 species, comprising 64 families, was assembled to carry identification tests. Percentage of correct identification (PCI) ranged from 42.8 to 100% when the score criterion of identification was used and from 88 to 100% when the results were order by percentage of identity. This evidences the importance of the method for ordering results. A list of 716 tree species of Semideciduous Seasonal Forest in the São Paulo state, comprising 80 families, was also a product of this work.
135

Low-energy domestic architecture : the impact of household behaviour on the expected energy use of passive house dwellings

Blight, Thomas January 2015 (has links)
Reduction of carbon emissions is understood to be vital to help mitigate catastrophic climate change. In Europe, 40% of energy use is attributed to the built environment (European Commission, 2010), with a large proportion of this from dwellings. In line other legislation for decarbonisation under the Climate Change Act of 2008, the UK Government has agreed that all new housing will be ‘zero carbon’ from 2016 onwards. From a technical aspect this task is feasible using improved insulation performance, more airtight building techniques, efficient servicing, and renewable energy technologies. In practice however, post-occupancy evaluation studies highlight a discrepancy between design energy use and measured energy performance, with a tendency for real buildings to use more energy than designed and for projects regarded as ‘low energy’ in design to use an equivalent amount of energy as a pre-existing counterpart (Bordass, 2001; Branco, Lachal, Gallinelli, & Weber, 2004; Gill, Tierney, Pegg, & Allan, 2011). This difference between design and use - ‘the design gap’ - is attributed to both the physical ‘hard’ features of the building (form, area, systems) and occupant-driven or ‘soft’ features (ventilation & heating preferences) by a number of studies (Guerra Santin, Itard, & Visscher, 2009; Socolow, 1978). This body of work begins with a review of the field and state of the art - occupant influence on energy use in a domestic environment. The first contribution to knowledge is in the adapted utilisation of a piece of software by Richardson et al. which stochastically generated electricity use profiles for homes which are shown to be similar to measured energy usage, both in net energy use and in load profiles (Richardson, Thomson, & Infield, 2008). This adapted software was implemented to generate appliance use profiles for a number of dwelling models. These results are then interrogated and a regression model proposed based on a number of dependent variables identified in the input profiles. The theory of planned behaviour is used to underpin a survey in which a number of households are asked to comment on their attitude and behaviour with regards to energy use in the home – the homes in this case being new-build Passivhaus council-housing in Devon. The results of this project form the second aspect of this work’s contribution to knowledge.
136

Household nutritional effects of the DICONSA food subsidy program

Dent, Felix January 2012 (has links)
This thesis is an empirical research project assessing the household nutritional impact of the DICONSA food subsidy program in Mexico. By employing a combination of propensity score matching and OLS econometric approaches, I conduct an analysis of household survey data contained in La Encuesta Nacional de Ingresos y Gastos de los Hogares (ENIGH) from Mexico. I find strong evidence of a significant increase in household caloric intake in rural areas targeted by the program, driven primarily by increased consumption of DICONSA subsidised cereal products and corn grain in particular. I find no evidence of decreased caloric intake resulting from overriding income effects of subsidisation. However, my investigation into the specifics of participant household food expenditure data suggests that reselling of subsidised commodities may occur amongst poorer households.
137

Lebensqualität bei Fabry-Patienten: Erhebung mit dem SF-36 Fragebogen / Quality of Life in patients with Fabry's disease: Investigation with the SF-36 questionnaire

Blohm, Elisabeth January 2012 (has links) (PDF)
Lebensqualität bei Fabry-Patienten: Erhebung mit dem SF-36®Fragebogen Elisabeth Blohm Hintergrund: Der Morbus Fabry ist eine X-chromosomal vererbte, lysosomale Speichererkrankung bedingt durch den Mangel an dem Enzym α-Galaktosidase A. Die gesundheitsbezogene Lebensqualität von Fabry-Patienten ist im Vergleich zur Normalbevölkerung oder Patienten anderer chronischer Erkrankungen sowohl bei physischen als auch psychischen Aspekten reduziert. Es ist bekannt, dass für den Morbus Fabry typische Symptome, wie Schmerzen oder Dysfunktionen lebenswichtiger Organe, wie Herz- und Niereninsuffizienz, sowie frühzeitige Schlaganfälle zu einer signifikant verringerten gesundheitsbezogenen Lebensqualität beitragen. Fragestellung: Ziel dieser Arbeit war es, mit Hilfe des SF-36-Fragebogens die gesundheitsbezogene Lebensqualität einer großen Kohorte von Fabry-Patienten zum Zeitpunkt der ersten Vorstellung in einem spezialisierten Fabry Zentrum zu ermitteln. Gleichzeitig sollten begleitende Faktoren identifiziert werden, die mit den verschiedenen Dimensionen der psychischen und physischen Funktionsfähigkeit assoziiert sind. Dabei legten wir einen Schwerpunkt auf die Nierenfunktion. Methoden: Es wurden 99 Patienten mit Morbus Fabry eingeschlossen. Wir untersuchten die Daten des ersten Besuchs in unserem Fabry-Zentrum. Die Patientencharakteristika der Studienteilnehmer und die verschiedenen Skalen der HRQoL wurden über die CKD-Stadien unter Verwendung von ANOVA, Kruskal-Wallis-Test, χ²-Test und Fisher’s-exact-Test verglichen. Die mit den verschiedenen Dimensionen der HRQoL assoziierten Faktoren wurden mittels einer linearen Regressionsanalyse untersucht. Im multivariaten Modell wurden die folgenden Variablen in das Modell aufgenommen: Alter, Geschlecht, Nierenfunktion, Schmerzen, Schmerztherapie und vaskuläres Ereignis. Ergebnisse: Die meisten Patienten, besonders die meisten Frauen, hatten eine erhaltene Nierenfunktion, wohingegen Patienten mit eingeschränkter Nierenfunktion mit höherer Wahrscheinlichkeit männlich waren. Alle Patienten, die einer RRT erhielten, waren männlich; zwei von ihnen erhielten eine Nierentransplantation, sieben waren unter Dialyse. Eine eingeschränkte Nierenfunktion, besonders die Notwendigkeit einer RRT war über allen Skalen mit einer deutlichen Reduktion der HRQoL assoziiert. Desweiteren waren männliches Geschlecht, Schmerzen und Schmerztheapie signifikant und deutlich mit niedrigeren Werten in den SF-36-Skalen assoziiert. Im multivariaten Modell stellten sich eine eingeschränkte Nierenfunktion und Schmerzen als die Hauptfaktoren für reduzierte Werte in den physikalischen Kategorien heraus (körperliche Funktionsfähigkeit, körperliche Rollenfunktion, körperliche Schmerzen, allgemeine Gesundheitswahrnehmung und körperlicher Summenwert). Im Gegensatz dazu stellte sich heraus, dass die Notwendigkeit einer RRT mit reduzierter HRQoL in den psychischen und sozialen Kategorien assoziiert war. Schlussfolgerung: In dieser großen Kohorte von Fabry-Patienten aus einem Zentrum war die chronische Nierenerkrankung, besonders die Notwendigkeit einer RRT, ein entscheidender Faktor mir eine reduzierte HRQoL in physischen und psychisch/sozialen Aspekten des Lebens. Außerdem hatten Schmerzen eine unabhängige Beziehung mit niedrigeren Werten der physischen Skalen. Neben der Enzymersatztherapie könnten eine optimale Behandlung der Nierenerkrankung, sowie eine effektive Schmerztherapie helfen, die HRQoL von Fabry-Patienten zu verbessern. / Health Related Quality of Life in Patients with Fabry Disease: Investigation with the SF-36® questionnaire Elisabeth Blohm Background Fabry disease is an X-linked lysosomal storage disorder caused by a deficiency of the enzyme α-galactosidase A. Health related quality of life (HRQoL) in patients with Fabry disease is reduced when compared to the healthy population and to other chronic diseases in physical as well as mental aspects of well-being. Fabry specific symptoms such as pain, vital organ dysfunction including heart and renal failure or premature strokes are known to contribute significantly to impaired HRQoL Aims The purpose of the current study was to characterize HRQoL as assessed by the SF-36® questionnaire in a large cohort of patients with Fabry disease of a single center. We aimed to identify factors associated with the various dimensions of physical and mental functioning, with a focus on kidney function. Methods 99 patients with Fabry disease were enrolled. We analyzed data from the first visit at our center. Characteristics of study participants and the different scales of HRQoL were compared across CKD stages (eGFR >60 ml/min vs. eGFR <60 ml/min vs. renal replacement therapy) using ANOVA, Kruskal-Wallis test, χ²- test, and Fisher’s exact test. Factors associated with the various dimensions of HRQoL were examined using linear regression analysis. In multivariate analyses, the following variables were included in the model: age, gender, kidney function, pain, pain-therapy, and vascular event. Results Most of the patients, in particular most women, had preserved kidney function, whereas patients with impaired kidney function were more likely to be male. All patients receiving RRT were of male gender, of which two underwent kidney transplantation and seven received dialysis. Impaired kidney function, particularly the need of RRT, was associated with markedly reduced HRQoL across all scales. Furthermore, male gender, pain and pain-therapy were significantly and meaningfully associated with lower scores on the SF-36 scales. In multivariate modeling, impaired kidney function and pain emerged as the main factors associated with lower scores in physical aspects of life (physical functioning, role physical, bodily pain, general health, PCS). In contrast, only the need for RRT was found to be associated with reduced HRQoL in mental/social parameter dimensions. Conclusion In this large cohort of Fabry patients recruited in a single center, chronic kidney disease, particularly the need of RRT, was a crucial factor for reduced HRQoL in physical and mental/social aspects of life. Furthermore, pain was independently related to lower scores on physical scales. Aside from enzyme replacement therapy, optimal treatment of kidney disease and an effective pain therapy may help to improve HRQoL in Fabry patients.
138

A SURVEY OF CANNABIS CONSUMPTION AND IMPLICATIONS OF AN EXPERIMENTAL POLICY MANIPULATION AMONG YOUNG ADULTS

Rudy, Alyssa K 01 January 2018 (has links)
The purpose of this online cross-sectional study was to identify cannabis user profiles by administration method and examine how differential cannabis policies influence intentions among young adults. Participants were assigned randomly to one of three hypothetical cannabis policy conditions (recreationally legal; medically legal; illegal). Within conditions, participants completed measures regarding cannabis use, including administration methods, cannabis attitudes, norms, perceived behavioral control, self-efficacy, and intentions. Latent class analysis (LCA) was used to determine sub-groups of past 30-day cannabis users by administration method followed by sub-group comparisons. Condition effects on intentions and associated variables were examined using ANCOVA. Four classes (Low-Blunt, Low-Bong, Mod-Poly, High-Poly) differing in demographics and tobacco use were identified. Recreationally and medically legal policy conditions resulted in more favorable cannabis attitudes, higher selfefficacy, and higher intentions to use compared to the illegal policy condition. Results inform cannabis intervention efforts and longitudinal research on the effects of cannabis policy changes.
139

A Survey in Mean Value Theorems

Neuser, David A. 01 May 1970 (has links)
A variety of new mean value theorems are presented along with interesting proofs and generalizations of the standard theorems. Three proofs are given for the ordinary Mean Value Theorem for derivatives, the third of which is interesting in that it is independent of of Rolle's Theorem. The Second Mean Value Theorem for derivatives is generalized, with the use of determinants, to three functions and also generalized in terms of nth order derivatives. Observing that under certain conditions the tangent line to the curve of a differentiable function passes through the initial point, we find a new type of mean value theorem for derivatives. This theorem is extended to two functions and later in the paper an integral analog is given together with integral mean value theorems. Many new mean value theorems are presented in their respective settings including theorems for the total variation of a function, the arc length of the graph of a function, and for vector-valued functions. A mean value theorem in the complex plane is given in which the difference quotient is equal to a linear combination of the values of the derivative. Using a regular derivative, the ordinary Mean Value Theorem for derivatives is extended into Rn, n>1.
140

Site-Based and Nonsite Archaeological Survey: A Comparison of Two Survey Methods in the City of Rocks, Idaho

McDonald, Patrick Reed 01 May 2015 (has links)
Pedestrian based archaeological survey is commonly used throughout the western United States to locate, identify, record, and interpret archaeological sites. While procedures, such as transect spacing, transect orientation, data collection, artifact documentation, and site criteria may vary, most survey methods share a common goal: to locate and define the boundaries of archaeological sites. Other researchers question the traditional site-based survey method. Critics suggest that site-based surveys may fail to adequately detect and document artifacts outside of site boundaries (Dunnell and Dancey 1983; Wandsnider and Camilli 1992). Site-based methods may not discern archaeological signatures of past cultures that occurred on the scale of landscapes rather than discrete sites (Ebert 1992; Robins 1998) In response, siteless approaches have been developed to test and address perceived shortcomings of site-based survey methods. The siteless survey utilizes artifacts as the basis for studying the relationships between clustered and non-clustered materials. This thesis examines traditional site-based survey vs. siteless survey within a study area in southern Idaho. Moreover, the study investigates the utility of the nonsite approach to identify spatial distributions, associations, and patterning in cultural materials on the surface of the analysis area. The results of the survey, data management and analyses evaluate if artifacts are randomly distributed or aggregated. Survey results compare the surveys’ effectiveness in detecting artifacts. In this comparison, the effects of artifact obtrusiveness/visibility are considered. Results of survey data are examined at different spatial scales to identify clusters and evaluate cluster attributes. Spatial patterning analyses use GIS software including the Getis Ord Gi* hot spot analysis tool and the buffer tool in ArcMap 10.2. Both GIS analyses successfully identified clustering. Finally, the results of analysis compare artifact cluster attributes identified by GIS analyses with site attributes. Siteless survey data and post-field, GIS analyses demonstrate the ability to offer information not available through traditional site-based survey. These results suggest that the siteless survey methods and analytic techniques employed in this study warrant further testing and evaluation.

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