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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.
71

Avaliação da influência da realização da expansão rápida da maxila sobre a recidiva do apinhamento ântero-superior, em casos tratados ortodonticamente sem extrações / Influence of rapid maxillary expansion in maxillary anterior alignment stability, in nonextraction cases

Canuto, Luiz Filiphe Gonçalves 11 December 2006 (has links)
O presente estudo objetivou comparar, por meio de uma análise retrospectiva, a estabilidade pós-contenção do alinhamento dos incisivos ântero-superiores de pacientes submetidos ou não ao procedimento de expansão rápida da maxila durante o tratamento ortodôntico. A amostra consistiu-se de 48 pacientes de ambos os gêneros, apresentando más oclusões de Classe I e II, tratados sem extrações e mecânica Edgewise. A amostra total foi dividida em dois grupos de acordo com o protocolo de tratamento: Grupo 1 (com ERM) constituído por 25 pacientes (15 do gênero feminino e 10 do gênero masculino), com idade inicial média de 13,53 anos (d.p. = ±1,63), submetidos à expansão rápida da maxila durante o tratamento ortodôntico. Grupo 2 (sem ERM) apresentando 23 pacientes (13 do gênero feminino e do 10 gênero masculino), com idade inicial de 13,36 anos (d.p. = ±1,81 anos), cujo tratamento ortodôntico não priorizou a expansão transversal maxilar. Foram medidos nos modelos de estudo das fases pré (T1), pós-tratamento (T2) e pós-contenção (T3) o índice de irregularidade de Little, as distâncias intercaninos e entre os primeiros e segundos pré-molares, a distância intermolares, o comprimento e o perímetro do arco superior. Após a obtenção dos dados, realizou-se a análise estatística. Para a comparação intragrupo nos 3 tempos de avaliação, utilizou-se a análise de variância a um critério de seleção, e em caso de resultado significante, o teste de Tukey. A comparação intergrupos foi realizada por meio de testes t independentes. Para verificação da presença de correlação entre a recidiva do apinhamento ântero-superior e a recidiva das variáveis: distâncias intercaninos, interpré-molares, intermolares, comprimento e perímetro do arco, utilizou-se o teste de correlação de Pearson. Os resultados evidenciaram incrementos dimensionais transversais significantemente maiores no grupo tratado com ERM (grupo 1), entretanto, durante o período pós-contenção, não foram observadas diferenças significantes entre os grupos em relação à quantidade de aumento na irregularidade dos incisivos superiores (+1,52 mm em ambos os grupos), bem como em relação à maioria das variáveis estudadas. Concluiu-se que a realização do procedimento de expansão rápida da maxila não apresentou influência na recidiva do apinhamento ântero-superior em longo prazo. / The purpose of this retrospective study was to compare the long-term stability of maxillary incisors alignment in cases treated with or without rapid maxillary expansion (RME) during orthodontic treatment. The sample comprised 48 subjects presenting Class I and Class II malocclusions, treated nonextraction and Edgewise fixed appliances. The sample was divided into 2 groups according to the treatment protocol: Group 1 (with RME) comprised 25 patients (15 female; 10 male) at a mean initial age of 13.53 years (s.d. = ±1.63), who underwent rapid maxillary expansion during orthodontic treatment. Group 2 (without RME) comprised 23 patients (13 female; 10 male) at a mean initial age of 13.36 years (s.d. = ±1.81 years), treated with fixed appliances and no rapid maxillary expansion. Dental casts measurements were obtained at three times of evaluation (pretreatment, posttreatment and postretention) and the variables assessed were Little Irregularity Index, intercanine, interpremolar and intermolar widths, and maxillary arch length and perimeter. The statistical analysis was performed by one-way ANOVA and Tukey tests if necessary (intragroup comparison) and by independent t-tests (Intergroup comparison). Pearson? correlation coefficients were used to investigate possible associations between the variables evaluated. The results evidenced significant transversal increases in group treated with RME (group 1), however, during the postretention period, no significant differences were observed between the groups in the amount of maxillary incisors alignment relapse (+1,52 mm in both groups), as well as in most of the variables evaluated. Therefore, it was concluded that the RME procedure did not influence the long-term maxillary anterior crowding relapse.
72

Painel portante estrutural com chapa de partículas de bagaço de cana-de-açúcar e resina de mamona para centro de manejo bovino / Structural self-bearing panel with sugarcane particleboards and castor oil resin for cattle handling facilities

Sartori, Diogo de Lucca 16 July 2012 (has links)
O presente trabalho teve por objetivo ajustar um processo para fabricação de chapas de partículas de bagaço de cana-de-açúcar e resina poliuretana bi componente à base de óleo de mamona, avaliar tecnicamente as propriedades físico-mecânicas, micro estrutural e de durabilidade desse material e validar seu uso como componente de painel portante para uso como fechamento lateral de instalações zootécnicas para bovino. A qualidade das chapas foi avaliada com base nas prescrições dos documentos normativos NBR 14810 (2006) e ANSI A208.1 (1999). Foram fabricados chapas com partículas com dimensão de até 5 e 8 mm, a fim de identificar a dimensão adequada dessa matéria-prima, para a aplicação das chapas na composição do painel portante. Posteriormente, foi desenvolvido e fabricado um protótipo de painel portante em madeira de reflorestamento e chapas de partículas de bagaço de cana-de-açúcar, que teve seu desempenho estrutural avaliado por meio de ensaio de impacto de corpo-mole. Os resultados obtidos indicam que as chapas com partículas de dimensão de até 8 mm apresentaram valores de propriedades físico-mecânicas que atendem as recomendações mínimas dos documentos normativos para uso estrutural. O painel portante apresentou desempenho estrutural adequado para resistir às cargas de impacto nas condições de uso, sendo possível indicá-lo com alternativa para fechamento lateral em centro de manejo para bovinos. / The objective of this study was to adjust a process for the manufacture of particleboards of sugarcane bagasse and bi-component polyurethane resin a base of castor oil, toevaluate its physic-mechanical properties, microstructure and durability of this material and to validate its use as component of self-bearing panel for use as a lateral closure of zootechnics installations for cattle. The particleboard quality was evaluated based on the requirements of normative documents NBR 14810 (2006) and ANSI A208.1 (1999). Particleboards were manufactured with particles size up to 8 and 5 mm, to identify the appropriate size of the raw material forthe application in particleboards for composition of the self-bearing panel. Then, a prototype ofself-bearing panel in reforestation wood and sugarcane particleboards it was developed and manufactured, which had its structural performance evaluated by soft body impact test. The results indicate that particleboards with particles size up to 8 mm showed values of physical-mechanical properties that met the minimum recommendations of the normative documents for structural use. The self-bearing panel showed adequate structural performance to withstand impact loads under the conditions of use and it can be designate asan alternative to closing side of cattle handling facilities.
73

Estudo comparativo do tempo de tratamento em pacientes com e sem apinhamento nos casos de má oclusão de Classe II tratados com extrações de quatro pré-molares / Comparative study of treatment times in patients with and without crowding in Class II malocclusion cases treated with extractions of four premolars

Silva, Lucas Nunes Bastos Curty 18 February 2013 (has links)
O objetivo deste trabalho foi comparar o tempo de tratamento em pacientes com e sem apinhamento apresentando inicialmente má oclusão de Classe II tratados com exodontia de quatro pré-molares. A amostra do estudo foi selecionada a partir do arquivo de modelos de gesso iniciais e pastas de pacientes já tratados na Faculdade de Odontologia de Bauru, no Departamento de Ortodontia. A amostra selecionada foi composta de 57 pacientes e dividida inicialmente em dois grupos. O grupo 1, que não apresentava apinhamento ou apresentava um leve apinhamento de 0 a 3 mm, foi constituído de 23 pacientes sendo 11 do gênero masculino e 12 do gênero feminino com idade inicial média de 13,13 anos (idade mínima de 10,67 e máxima de 18,25). O grupo 2, que apresentava apinhamento igual ou maior a 4 mm, foi constituído de 34 pacientes sendo 19 do gênero masculino e 15 do gênero feminino com idade inicial média de 13,07 anos (idade mínima de 11,08 e máxima de 18,33). Para comparar os tempos de tratamento dos grupos, a análise estatística feita foi o teste t, pois os dados obtidos apresentavam uma distribuição normal. Os resultados mostraram que não há diferença estatisticamente significante entre os tempos de tratamento do grupo 1 (2,51 anos) e do grupo 2 (2,49 anos). Sendo assim, os resultados sustentam a ideia de que o principal fator responsável pela semelhança entre os tempos de tratamento é a necessidade da correção anteroposterior do molar, que é igual para ambos os grupos. / The objective of this study was to compare the treatment time of bilateral complete Class II malocclusion with and without crowding treated with four premolar extractions, The sample was selected from arquive of beginning models and pastes of pacients treated at Bauru Dental School, department of Orthodontics. The selected sample was composed by 57 patients and divided into two groups. Group 1 presented no crowding or crowding 0-3 mm was composed by 23 patients being 11 male and 12 female with a mean age of 13,13 years (minimum age 10,67 and maximum age 18,25). Group 2 presented crowding 4 mm or more was composed by 34 patients being 19 male and 15 female with a mean age of 13,07 years (minimum age of 11,08 and maximum age of 18,33). To compare treatment times between groups, t test was performed. Results demonstrated that there was not significantly difference in treatment times of group 1 (2,51 years) and 2 (2,49 years). Thus, the results support the idea the principal factor responsible for similarity treatment times is the need of the molar relationship correction, which is similar in both groups.
74

Avaliação da influência da realização da expansão rápida da maxila sobre a recidiva do apinhamento ântero-superior, em casos tratados ortodonticamente sem extrações / Influence of rapid maxillary expansion in maxillary anterior alignment stability, in nonextraction cases

Luiz Filiphe Gonçalves Canuto 11 December 2006 (has links)
O presente estudo objetivou comparar, por meio de uma análise retrospectiva, a estabilidade pós-contenção do alinhamento dos incisivos ântero-superiores de pacientes submetidos ou não ao procedimento de expansão rápida da maxila durante o tratamento ortodôntico. A amostra consistiu-se de 48 pacientes de ambos os gêneros, apresentando más oclusões de Classe I e II, tratados sem extrações e mecânica Edgewise. A amostra total foi dividida em dois grupos de acordo com o protocolo de tratamento: Grupo 1 (com ERM) constituído por 25 pacientes (15 do gênero feminino e 10 do gênero masculino), com idade inicial média de 13,53 anos (d.p. = ±1,63), submetidos à expansão rápida da maxila durante o tratamento ortodôntico. Grupo 2 (sem ERM) apresentando 23 pacientes (13 do gênero feminino e do 10 gênero masculino), com idade inicial de 13,36 anos (d.p. = ±1,81 anos), cujo tratamento ortodôntico não priorizou a expansão transversal maxilar. Foram medidos nos modelos de estudo das fases pré (T1), pós-tratamento (T2) e pós-contenção (T3) o índice de irregularidade de Little, as distâncias intercaninos e entre os primeiros e segundos pré-molares, a distância intermolares, o comprimento e o perímetro do arco superior. Após a obtenção dos dados, realizou-se a análise estatística. Para a comparação intragrupo nos 3 tempos de avaliação, utilizou-se a análise de variância a um critério de seleção, e em caso de resultado significante, o teste de Tukey. A comparação intergrupos foi realizada por meio de testes t independentes. Para verificação da presença de correlação entre a recidiva do apinhamento ântero-superior e a recidiva das variáveis: distâncias intercaninos, interpré-molares, intermolares, comprimento e perímetro do arco, utilizou-se o teste de correlação de Pearson. Os resultados evidenciaram incrementos dimensionais transversais significantemente maiores no grupo tratado com ERM (grupo 1), entretanto, durante o período pós-contenção, não foram observadas diferenças significantes entre os grupos em relação à quantidade de aumento na irregularidade dos incisivos superiores (+1,52 mm em ambos os grupos), bem como em relação à maioria das variáveis estudadas. Concluiu-se que a realização do procedimento de expansão rápida da maxila não apresentou influência na recidiva do apinhamento ântero-superior em longo prazo. / The purpose of this retrospective study was to compare the long-term stability of maxillary incisors alignment in cases treated with or without rapid maxillary expansion (RME) during orthodontic treatment. The sample comprised 48 subjects presenting Class I and Class II malocclusions, treated nonextraction and Edgewise fixed appliances. The sample was divided into 2 groups according to the treatment protocol: Group 1 (with RME) comprised 25 patients (15 female; 10 male) at a mean initial age of 13.53 years (s.d. = ±1.63), who underwent rapid maxillary expansion during orthodontic treatment. Group 2 (without RME) comprised 23 patients (13 female; 10 male) at a mean initial age of 13.36 years (s.d. = ±1.81 years), treated with fixed appliances and no rapid maxillary expansion. Dental casts measurements were obtained at three times of evaluation (pretreatment, posttreatment and postretention) and the variables assessed were Little Irregularity Index, intercanine, interpremolar and intermolar widths, and maxillary arch length and perimeter. The statistical analysis was performed by one-way ANOVA and Tukey tests if necessary (intragroup comparison) and by independent t-tests (Intergroup comparison). Pearson? correlation coefficients were used to investigate possible associations between the variables evaluated. The results evidenced significant transversal increases in group treated with RME (group 1), however, during the postretention period, no significant differences were observed between the groups in the amount of maxillary incisors alignment relapse (+1,52 mm in both groups), as well as in most of the variables evaluated. Therefore, it was concluded that the RME procedure did not influence the long-term maxillary anterior crowding relapse.
75

An examination of the relationship between population density, density related social factors, and physical morbidities

Huebner, Douglas King 20 April 1976 (has links)
The relationship between the number of persons per room in the home and the relative occurrence of stress-related morbidities of hospitalized patients is investigated. The social factors of age, social class, and level of social support also are examined as they relate to both density and morbidity type occurrence. The population under study is composed of all Kaiser-Permanente Medical Care Program members twenty years of age and older, discharged from Bess Kaiser Hospital during 1974, and whose diagnosed morbidity was included in specific morbidity categories. All data were obtained through the facilities of the Health Services Research Center, Kaiser Foundation Hospital, Portland, Oregon. The data are largely ordinal in nature, and are presented in the form of contingency tables, utilizing chi square and Tau B as measures of degree of association and strength of relationship. An interval level of measurement is obtained through dichotomization of the variables and the derivation of Pearsonian correlation coefficients, and regression coefficients which are utilized in path analysis. The findings indicate that higher residential population density is related to disproportionate occurrence of some, but not all, stress-related morbidities, and that some stress-related morbidities are associated with low population density. However, in comparing stress-related morbidities with non-stress related morbidities, it is found that more stress-related morbidity categories tend to be over-represented in the higher density regimes than those morbidities categorized as non-stress related. In addition, it is found that those stress-related morbidities that exhibit such a pattern of over-representation maintain it, in general, regardless of the controls applied. Age is found to be negatively related to density and to the occurrence of stress-related morbidities, while being positively related to socioeconomic status. Socioeconomic status is found to be negatively related to both stress-related morbidity occurrence and to density. Social support is positively related to both density and to the occurrence of stress-related morbidities, but appears to have no relationship to either age or class. Hospital during 1974, and whose diagnosed morbidity was included in specific morbidity categories" All data were obtained through the facilities of the Health Services Research Center, Kaiser Foundation Hospital, Portland, Oregon.
76

Membrane mediated aggregation of amyloid-β protein : a potential key event in Alzheimer's disease

Bokvist, Marcus January 2007 (has links)
The pathogenesis of Alzheimer’s disease (AD), the most common senile dementia, is a complex process. A crucial event in AD is the aggregation of amyloid-β protein (Aβ), a cleavage product from the Amyloid Precursor Protein (APP). Aβ40, a common component in amyloid plaques found in patients, aggregates in vitro at concentrations, much higher than the one found in vivo. But in the presence of charged lipid membranes, aggregations occurs at much lower concentration in vitro compared to the membrane-free case. This can be understood due to the ability of Aβ to get electrostatically attracted to target membranes with a pronounced surface potential. This electrostatically driven process accumulates peptide at the membrane surface at concentrations high enough for aggregation while the bulk concentration still remains below threshold. Here, we elucidated the molecular nature of this Aβ-membrane process and its consequences for Aβ misfolding by Circular Dichroism Spectroscopy, Differential Scanning Calorimetry and Nuclear Magnetic Resonance Spectroscopy. First, we revealed by NMR that Aβ40 peptide does indeed interact electrostatically with membranes of negative and positive surface potential. Surprisingly, it even binds to nominal neutral membranes if these contain lipids of opposite charge. Combined NMR and CD studies also revealed that the peptide might be shielded from aggregation when incorporated into the membrane. Moreover, CD studies of Aβ40 added to charged membranes showed that both positively and negatively membranes induce aggregation albeit at different kinetics and finally that macromolecular crowding can both speed up and slow down aggregation of Aβ.
77

Spatial interaction and local government expenditures for functionally impaired in Sweden

Birkelöf, Lena January 2009 (has links)
The thesis consists of an introductory part and three self-contained papers. Paper [I] studies the determinants of the differences in expenditure on services for functionally impaired individuals among municipalities in Sweden. A spatial autoregressive model is used in order to test whether the decisions on the expenditure level in a neighboring municipality affect the municipality’s own expenditure. The results show of spatial interaction among neighbors, possible due to mimicking. However, when controlling for differences among counties there is no evidence of spatial interaction. Therefore, the positive interaction first found can be interpreted either as a result of differences in the way county councils diagnose individuals or due to interaction among the neighbors in the same county. Paper [II] takes advantage of a new intergovernmental grant in two ways. First, the grant is used to study the effect on municipal spending related to the grant. Second, the grant is used to test a hypothesis of spatial interaction among municipalities due to mimicking behavior. The data used pertains to the periods before and after the introduction of the grant. A fixed-effects spatial lag model is used to study the spatial interactions among municipalities. The results show that before the grant, municipalities interact with their neighbors when setting the expenditure level, while there is no evidence of interaction in the second period. This would support the hypothesis that the grants provide information to the municipalities and the need for mimicking diminishes with the grant. Paper [III] examines whether local public expenditures on services to functionally impaired individuals crowd out other local public expenditures in Sweden. The hypothesis is tested on five different spending areas using a two-stage least squares (2SLS) fixed-effects model. While the results give no support for crowding out in the areas of social assistance, culture & leisure, and childcare & preschool, a negative relationship on spending for elderly & disabled care and on spending for education is found, suggesting that crowding out indeed occurs within the municipal sector. The negative relationships are significant both in a statistical and an economic sense.
78

Toward an Understanding of the Revenue of Nonprofit Organizations

Horne, Christopher Scott 01 September 2006 (has links)
Understanding the composition and distribution of the revenue of nonprofit organizations (NPOs) is key to understanding NPOs themselves. This research uses revenue data for 87,127 charitable NPOs to draw three main conclusions. First, revenue structures of NPOs vary widely by subsector and organizational size, with many NPOs demonstrating revenue structures that might be considered uncharacteristic of the nonprofit sector. Second, despite the concerns of many nonprofit scholars, heavy dependence on either government funding or charitable contributions is atypical of NPOs. And third, nonprofit revenue is highly concentrated in relatively few NPOs. The description of revenue expands to examine the relationship between two important sources of revenue, charitable contributions and government subsidies. Nonprofit scholars have long theorized that government funding diminishes charitable giving. This research finds that the effect of subsidy on charity varies substantially among the nonprofit subsectors, but, contrary to widely accepted theory, these effects are more often positive than negative: More than half of government funding of the nonprofit subsectors appears to spur an increase in charitable giving, whereas only 6 percent of government funding is associated with decreased giving. This research suggests that effects of subsidy on charity are less likely due to the decisions of donors than to the decisions of NPOs themselves. These findings assuage some concerns about the future of the nonprofit sector but substantiate others. As government increasingly relies on NPOs to deliver government-funded services, it appears unlikely that NPOs will suffer decreases in charitable giving, and government funding may even enable NPOs to increase revenue from charitable giving. But marginal changes in charitable giving will not mitigate what many see as a distressing move away from reliance on charity toward generating fees for services and generally becoming more business-like. Whether these findings represent a nonprofit sector betraying its charitable roots, diluting its power to effect social change by "corporatizing," emphasizing service delivery at the expense of advocacy, or becoming more efficient, financially stable, and responsive to market demands remains a matter of debate, but debate better informed by the understanding of nonprofit revenue provided by this research.
79

Effects of Intrinsic and Extrinsic Motivation on Individuals Knowledge-Sharing Behavior in Virtual Communities

Liu, Chih-Chung 18 August 2010 (has links)
The rapid growth of network access and the development of Web 2.0 have resulted in the popularity of virtual communities (VCs), such as Wikipedia, Facebook, and LinkedIn. Although these online communities provide no monetary incentive for sharing knowledge, as most businesses will do, they still become a popular platform for knowledge sharing. The purpose of this study is to investigate the motivation for people to contribute in virtual communities, whether their motivations differ in different types of virtual communities, and whether their behavior and motivations will be affected by monetary reward. Social exchange theory and self determination theory were adopted to explore the relationships between behavior and motivations of virtual community members. Motivation crowding theory was used to examine the effect of monetary reward on knowledge sharing. The research framework includes two types of motivators (intrinsic and extrinsic), two different virtual community types (common identity vs. common bond), and one treatment (monetary reward). An online survey and an experiment with monetary incentive were conducted on two virtual communities: ITToolbox and LinkedIn. The results showed that there were significant moderating effects between these two types of virtual communities. A strong positive relationship was found between intrinsic motivation and knowledge sharing for the professional community (common identity). In contrast, the relationship between extrinsic motivation and knowledge sharing was stronger in the social networking community (common bond). The results also confirmed the existence of the crowding effect that the intrinsic motivation was significantly declined when an extrinsic monetary reward was provided.
80

Evaluation of Ambulance Diversion

Huang, Chung-Yeh 10 February 2012 (has links)
The problem of overcrowding is one of the serious issues that almost every emergency department (ED) in Taiwan has to face on daily basis. ED crowding results in adverse medical outcomes, decline in quality of care, and lack of the ability to provide instant medical care. One of the viable (but not necessarily preferable) solutions to ED overcrowding is ambulance diversion (AD). That is, ambulances would bypass the ED¡¦s unable to provide emergency medical service, and send patients to another emergency department. In many medical systems, ambulance diversion is being seen as a standard operating procedure, whose effectiveness needs to be carefully studied before making a sound policy. In this research, an input-throughput-output simulation model is proposed for simulating ED operation. A computer simulation program is developed based on this model to evaluate various AD initiating criteria, patient-blocking rules, and AD intervals. The crowdedness index, the patient waiting time for service, and the percentage of adverse patients were assessed to determine the impact of various AD policies. By appropriate parameter settings, this simulation model can represent medical resource providers of different scales. The results we obtained may offer insights for making effective AD policies.

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