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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.
21

[en] O TERROR DA VERMELHA: AN ANALYSIS PROPOSAL OF INCOMPLETUDE / [pt] O TERROR DA VERMELHA: UMA PROPOSTA DE ANÁLISE A PARTIR DA INCOMPLETUDE

JULIA SOUZA CABO 21 July 2016 (has links)
[pt] Este trabalho constitui um estudo sobre as formas como Torquato Neto, ator importante nas movimentações culturais do Brasil durante as décadas de 1960 e 1970, se inseriu no campo do cinema brasileiro. Para realizar tal estudo optou-se por centrar a análise no filme O Terror da Vermelha, de 1972, o único filme dirigido por Torquato Neto ao longo de sua vida. O Terror da Vermelha, no entanto, nunca foi finalizado por Torquato, que cometeu suicídio poucos meses depois das filmagens, deixando apenas as imagens filmadas e um vago roteiro na forma de poema. Foi, portanto, no exercício de tentar-se uma aproximação de uma fonte tão singular que essa pesquisa foi construída. Para tanto, partiu-se de uma concepção de O Terror da Vermelha como um filme em aberto, um objeto que habita o espaço entre a fantasia do filme desejado e o produto acabado, o que configurou uma abordagem da película que engloba não somente as imagens criadas, mas também todos os escritos de Torquato que falam sobre cinema e seu desejo de produzir filmes. / [en] The following thesis is a study on the many ways in which Torquato Neto, a key figure in Brazil s cultural movements during the 1960s and 1970s, approached the cinematographic field. The thesis is centered around the analysis of the 1972 short film O Terror da Vermelha, the only film which Torquato Neto directed during his life. However, O Terror da Vermelha was never finished by Torquato, who committed suicide a few months after the filming was finished, leaving only the filmed footage and a vague script in the form of a poem. Therefore, this thesis was built as an exercise on how to approach such singular object. To do so, our starting point was to conceive O Terror da Vermelha as an open film, an object that inhabits the space between the fantasy of a desired film and a finished product, which configures an approach to film which encompasses not only the created images, but also all of Torquato written production on cinema and on his desire to do films.
22

Análisis comparativo in vitro del sellado marginal de restauraciones de resina compuesta activadas con lámpara convencional y lámpara L. E. D.

Carrillo Godoy, Alejandra January 2005 (has links)
No description available.
23

Application of Marginal Structural Models in Pharmacoepidemiologic Studies

Yang, Shibing 01 January 2014 (has links)
Background: Inverse-probability-of-treatment-weighted estimation (IPTW) of marginal structural models was proposed to adjust for time-varying confounders that are influenced by prior treatment use. It is unknown whether pharmacoepidemiologic studies that applied IPTW conformed to the recommendations proposed by methodological studies. In addition, no previous study has compared the performance of different analytic strategies adopted in IPTW analyses. Objectives: This project aims 1) to review the reporting practice of pharmacoepidemiologic studies that applied IPTW, 2) to compare the validity and precision of several approaches to constructing weight, 3) to use IPTW to estimate the effectiveness of glucosamine and chondroitin in treating osteoarthritis. Methods: We systematically retrieved pharmacoepidemiologic studies that were published in 2012 and applied IPTW to estimate the effect of a time-varying treatment. Under a variety of simulated scenarios, we assessed the performance of four analytic approaches what were commonly used in studies conducting IPTW analyses. Finally, using data from Osteoarthritis Initiative, we applied IPTW to estimate the long-term effectiveness of glucosamine and chondroitin on treating knee osteoarthritis. Results: The practice of reporting use of IPTW in pharmacoepidemiologic studies was suboptimal. The majority of reviewed studies did not report that the positivity assumption was assessed, and several studies used unstablized weights or did not report that the stabilized weights were used. With data simulation, we found that intention-to-treat analyses underestimated the actual treatment effect when there was non-null treatment effect and treatment non-adherence. This underestimation was linearly correlated with adherence levels. As-treated analyses that took into account the complex mechanism of treatment use generated approximately unbiased estimates without sacrificing the estimate precision when the treatment effect was non-null. Finally, after adjustment for potential confounders with marginal structural models, we found no clinically meaningful benefits of glucosamine/chondroitin in relieving knee pain, stiffness and physical function or slowing joint space narrowing. Conclusions: It may be prudent to develop best practices of reporting the use of IPTW. Studies performing intention-to-treat analyses should report the levels of adherence after treatment initiation, and studies performing as-treated analyses should take into the complex mechanism of treatment use in weight construction.
24

Avaliação "in vitro" da infiltração marginal em função da configuração cavitária e de materiais restauradores estéticos

Lopes, Lawrence Gonzaga 15 December 2000 (has links)
O objetivo deste trabalho foi avaliar a infiltração marginal de restaurações cervicais em função do fator de configuração cavitária (FC) e de quatro materiais restauradores estéticos. Cavidades convencionais com FC=5, e em forma de “pires" com FC<5 foram realizadas, respectivamente, nas faces distais e mesiais de 60 prémolares recém-extraídos. Para a primeira cavidade, utilizou-se uma ponta diamantada troncocônica com dimensões especiais (2,9 mm x 2,5 mm (base menor) x 1,5 mm de profundidade). A cavidade em forma de “pires" apresentou dimensões proporcionais ao diâmetro da ponta diamantada esférica n.3018 (2,9 mm) e, também, com profundidade de 1,5 mm, sendo que as margens das cavidades localizaram-se em esmalte e cemento/dentina. Os seguintes grupos foram estabelecidos: G1 (Z100/Single Bond-3M), G2 (Freedom/Stae–SDI), G3 (Vitremer/Primer–3M) e G4 (Durafill/Durafill Bond-Kulzer). Os sistemas restauradores foram aplicados conforme as orientações de cada fabricante. A termociclagem dos espécimes compreendeu 10 ciclos/dia nas temperaturas de 37ºC, 5ºC e 55ºC, com permanência de 1,5 minuto. Esses procedimentos foram repetidos pelo período de sete dias, totalizando 70 ciclos, sendo que no último dia a ciclagem foi feita em solução aquosa tamponada de azul de metileno a 2%. Em seguida os espécimes foram seccionados, fotografados em estereomicroscópio, com aumento de 16X, e depois avaliados por dois examinadores pela projeção das fotografias. Os valores foram submetidos à análise de Kruskal-Wallis a um critério, Dunn; Wilcoxon; e Friedman, Student-Newman-Keuls. As médias dos escores de infiltração observados na cavidade convencional e naquela em forma de “pires" foram, respectivamente: G1- 0,66 / 0,46; G2- 0,92 / 0,69; G3- 1,8 / 1,86; G4- 3,54 / 2,3. Portanto, o fator de configuração cavitária não exerceu, de maneira geral, influência significativa para os diferentes sistemas restauradores. Com exceção do sistema Durafill/Durafill Bond, que apresentou os maiores graus de infiltração marginal, os demais materiais comportaram-se de forma semelhante. / The aim of this work was to evaluate the cervical restorations marginal leakage in regard with the cavity configuration factor (CF) and four esthetic restorative materials. Conventional cervical cavities with CF=5 and other "Saucer"- like cavities with CF<5, were carried out on the distal and mesial surfaces, in 60 freshly extracted premolars. For the first cavity, a trunk-conic diamond bur with special dimensions (2.9mm x 2.5 mm x 1.5mm) was used. The "Saucer"-like cavity had dimensions proportional to the diamond bur diameter #3018 (2.9 mm), and the depth determined in 1.5 mm. The cavities margins were set either in cement/dentin or enamel. Some groups were established: G1 (Z100/Single Bond-3M), G2 (Freedom/Stae-SDI), G3 (Vitremer/Primer-3M) and G4 (Durafill/Durafill Bond). These restorative systems were used according to their manufacters' directions. The specimens were submitted to 10 cycles/day at the temperatures 37ºC, 5ºC and 55ºC, exposing the teeth to 1.5 minutes. Seven thermocyclings (7 days) were performed, totalizing 70 cycles, but at the last one, the thermocycling was done in 2% buffered methylene blue aqueous solution. The specimens were thereafter sectioned, photographed under a stereomicroscope at 16X magnification, and the obtained photographs were assessed by two trained examiners. The results were evaluated through the Kruskal-Wallis one way analysis, Dunn's multiple comparisons method; Wilcoxon; and Friedman, Student-Newman-Keuls methods. The means scores of the marginal leakage concerning the conventional cavity and the "Saucer"-like cavity, were respectively: G1- 0.66 / 0.46; G2- 0.92 / 0.69; G3- 1.8 / 1.86; G4- 3.54 / 2.3. Hence, the cavity configuration factor didn’t have, at all, a significant influence to the different restorative materials. Except for the Durafill/Durafill Bond system, that presented the greatest degrees of marginal leakage, the other restorative materials had the same behavior.
25

Estudo 'In Vitro' da Infiltração Marginal em Dentes Submetidos a Diferentes Técnicas de Clareamento e Restaurados com um Sistema Adesivo/Resina Composta.

Souza, Patrícia de Almeida Rodrigues da Silva e 05 August 1999 (has links)
Foi avaliado o efeito do clareamento na infiltração marginal de dentes restaurados com o sistema adesivo Scotchbond Multi-uso Plus e resina composta Z-100. Sessenta pré-molares foram divididos em 6 grupos: grupo I, técnica imediata, uma bolinha de algodão saturada em peróxido de hidrogênio a 30% foi colocada no interior da câmara coronária e na superfície vestibular dos dentes e aquecida a uma temperatura de 42ºC por 3 períodos de 15 minutos, num total de três sessões semanais; grupo II, técnica mediata, era selado um curativo na câmara coronária de peróxido de hidrogênio a 30% mais perborato de sódio por 21 dias, e no intervalo de sete dias renovado; grupo III, associação das duas técnicas acima descritas; grupo IV, técnica caseira com aplicação de peróxido de carbamida a 10% por três horas diárias durante 21 dias; grupo V, associação da técnica caseira mais mediata; grupo VI foi o controle que não foi submetido ao tratamento clareador. Após, todos os grupos permaneceram com um curativo de hidróxido de cálcio por dez dias, para em seguida serem restaurados, termociclados e imersos em fucsina básica à 0,5% por 24 horas. A medida da penetração do corante pela interface dente restauração foi realizada através do programa ImageTool. As médias obtidas foram de 3,09; 1,83; 2,11; 2,36; 1,60 e 2,20(mm) para os grupos de I ao VI, respectivamente. Nenhum grupo impediu a infiltração marginal; a técnica imediata mostrou os maiores valores de infiltração, diferente estatísticamente dos grupos II e V; nos grupos onde aplicou-se o perborato de sódio houve uma tendência a menor infiltração. Não houve diferença entre as demais técnicas e estas em relação ao grupo controle. / The effects of different bleaching techniques on the dental structures were assessed using microleakage tests. Sixty pre molars were used in this study according to the following procedures: group I – a cotton pellet saturated with 30% hydrogen peroxide was placed in the pulp chamber and on the buccal surface and heated to 42 oC three times of fifteen minutes each. This procedures was repeated three times. Group II - In the pulp chamber was inserted a paste of sodium perborate and 30% hydrogen peroxide for 21 days. Every seven days the material was renewed. Group III – The two techniques described above were associated. Group IV – 10% carbamide peroxide was applied on the external surfaces three hours per day during 21 days (home bleaching) Group V – Association of group II and IV techniques. Group VI- No treatments were performed in this group (Control). A CaOH2 paste was sealed in the pulp chamber for 10 days, the teeth were restored with Scotchbond Multi-uso Plus/Z-100, thermocycled and immersed in basic fucsin. The die penetration was determined in mm using the software Imagetool. The means (mm) of die penetration for groups I to VI were: 3,09; 1,83; 2,11; 2,36; 1,60; and 2,20. The microleakage occurred regardless the bleaching procedures. Group I technique exhibited higher die penetration when compared to groups II and V. The groups where sodium perborate was applied there was a trend of less die penetration.
26

Efeito do bisel na infiltração marginal em restaurações classe IV de resina composta

Mizuno, Sérgio Katsuo 14 February 2003 (has links)
O objetivo deste estudo foi avaliar o efeito do bisel na infiltração marginal em restaurações de resina composta em cavidades Classe IV sem e com bisel em todo ângulo cavossuperficial, submetidas à ciclagem térmica e mecânica. Foram preparadas nas mesmas dimensões, variando na ausência ou presença de bisel, 30 cavidades de Classe IV em incisivos inferiores de bovinos. No grupo 1 não foi realizado bisel e no grupo 2 o bisel foi realizado com uma extensão aproximada de 1,0 mm ao redor de todo o ângulo cavossuperficial. As cavidades foram restauradas com o mesmo sistema adesivo e resina composta Single Bond Z-250 (3M). Após a restauração foi executado um acabamento inicial com lâminas de bisturi. Em seguida, os dentes foram armazenados em água deionizada a uma temperatura de 37ºC durante sete dias. No sétimo dia foi realizada a complementação do acabamento e polimento. Os grupos foram submetidos à ciclagem térmica com o tempo de imersão de 30 segundos em cada banho, a uma temperatura de 5 ºC e 55ºC, por 500 ciclos. Logo após, os corpos-de-prova foram submetidos à ciclagem mecânica, utilizando a máquina universal de ensaio EMIC programada para executar um carregamento e descarregamento axial de compressão na face lingual de cada dente restaurado. Inicialmente, foi aplicada uma carga ascendente de 1 a 10 kgf e descendente de 10 a 1 kgf durante 30 segundos, perfazendo um total de 100 ciclos para cada corpo-de-prova. Durante este ensaio, a porção coronária dos dentes ficou submersa em fucsina básica a 0,5 %. Após o término da ciclagem mecânica, os corpos-de-prova permaneceram por mais 24 horas mergulhados na mesma solução e, em seguida, foram lavados em água corrente por 12 horas. Cada dente foi seccionado em fatias transversais de aproximadamente 1,0 mm, sendo selecionada a fatia que apresentou maior grau de infiltração. Para avaliação da infiltração marginal foi utilizado um programa de análise de imagens, Image Tools, no qual foi medida a extensão da penetração do corante em milímetros. Os valores em milímetros da extensão de penetração do corante foram para os grupos 1 e 2; sendo 1,02 mm e 0,0 mm respectivamente. Aplicando o teste estatístico, verificou-se que houve diferença estatisticamente significante (p < 0,05) entre os valores de infiltração do grupo 1 (ausência de bisel) com os do grupo 2 (presença de bisel). Concluiu-se que a presença do bisel diminui significativamente a infiltração marginal nas restaurações de Classe IV, restaurações estas confeccionadas com o sistema restaurador adesivo e resina composta. / The purpose of this study was to evaluate the effect of bevel in the microleakage in restorations of composite resin, in cavities Class IV with bevel and without bevel around all the cavosurface margins, submitted to a thermal and mechanical cycled. The same dimensions was prepared, varying in the bevel presence or absence, thirty cavites of Class IV bovine teeth. Thereby, in group 1 the bevel was not done and in group 2 the bevel of 1 mm length was done around all the cavosurface margins. The cavities was restored with Single Bond / Z-250 (3 M). After restored, all restorations were finished with a scalpel. Afterwards, they were stored in deionize water at 37º C for seven days followed by the polishing procedures. All the groups were submitted to thermocycling 500 times between 5 ºC and 55 ºC, in a 30 seconds dwell time. For the mechanical cycled test, it was used the EMIC machine which was programmed to execute an axial load of 10 kgf, during 30 seconds in the lingual surface of the restorations. During the mechanical cycled test, the crown of the teeth remained submerse in a 0,5% basic fuchsin, and continued submerse until 24 hours had been completed. After that, the teeth were left 12 hours in the running water, followed by the section. Each tooth was parted in transversal sections with approximately 1,0 mm and the section with the higher amount of dye penetration was selected. It was used a program (Image Tool) to make possible an analysis of the images, to determined the dye penetration in milimeters. Through the results it is clearly that, there was a significant statistic difference (p < 0,05) between group 1 (absence of bevel) and group 2 (presence of bevel), which had 1,02 mm and 0,0 mm averages of dye penetration respectively. It was concluded that the procedure of bevel execution reduce expressively the microleakage around the margins of the restorations.
27

Avaliação da Infiltração Marginal em Cavidades de Classe II Restauradas com Resina Composta Associada a Outros Materiais de Inserção Direta.

Mondelli, Adriano Lia 20 December 1999 (has links)
As resinas compostas vêm sofrendo inúmeras alterações, com o objetivo de tornar o seu uso adequado para restaurações de dentes posteriores, entretanto, problemas clínicos associados à sua utilização são comumente observados, dentre eles, a microinfiltração marginal. Algumas alternativas clínicas têm sido sugeridas, na tentativa de reduzir as falhas decorrentes do emprego deste material, principalmente em restaurações estendidas à região de cemento, local este onde os problemas se agravaram. O objetivo deste trabalho consistiu, portanto, em estudar a efetividade do vedamento marginal de diferentes materiais aplicados no terço cervical com término em cemento para, em associação à resina composta, restaurar esteticamente cavidades de classe II, através da técnica mista, avaliando-se com esta finalidade o índice de infiltração marginal na interface cemento/material restaurador. Cavidades M.O.D. com margens cervicais estendidas além da junção amelocementária foram confeccionadas em 60 pré-molares humanos livres de cáries, os quais foram distribuídos em grupos de 10 elementos cada, correspondendo a 5 condições experimentais: Grupo controle – em todos os dentes, Scotchbond MP / Z-100; Grupo 1 - Scotchbond MP (Concise) / Concise / Scotchbond MP / Z-100; Grupo 2 – Alpha Bond / Natural Flow / Scotchbond MP / Z-100; Grupo 3 – One step / Aeliteflo / Scotchbond MP / Z-100; Grupo 4 – Prime & Bond 2.1 / Dyract-AP / Scotchbond MP / Z-100; Grupo 5 – Verniz copalite / Velvalloy / Scotchbond MP / Z-100; No sentido de evitar penetração da solução corante em áreas indesejadas. Em todos os dentes os forames apicais foram obstruídos com Scotchbond MP / Z-100. Após 48 horas, as restaurações foram polidas com discos Sof-Lex de granulação fina e submetidas posteriormente a um teste de ciclagem por carregamento oclusal correspondendo a 200 ciclos de 1 a 17kg. Imediatamente após a ciclagem, os espécimes foram armazenados 24 horas em água destilada a 370C. Após este período tiveram a superfície totalmente coberta por uma camada de esmalte de unha, exceto 1mm aquém e além da interface cemento/ material restaurador. Depois foram termociclados em azul de metileno a 2% correspondendo a 180 ciclos de 45 segundos cada, nas temperaturas de 50C, 370C e 550C . Os corpos de prova foram armazenadas em azul de metileno a 2% por mais 24 horas a 370C. Decorrido este período os dentes foram incluídos em bases acrílicas apropriadas para serem adaptadas à máquina de corte, obtendo-se cerca de 3 cortes para cada espécime. Para avaliar o índice de penetração da solução corante nas interfaces cemento/material restaurador, optou-se pela análise qualitativa, através da atribuição de escores previamente determinados. Os resultados obtidos foram então organizados e submetidos aos cálculos estatísticos, concluíndo-se que: • amálgama Velvalloy e a resina composta Z-100 usada como controle apresentaram respectivamente os índices mais severos de infiltração marginal, na interface cemento/material restaurador; • Houve diferença estatística significante entre o Dyract-AP e os demais materiais testados o qual reduziu consideravelmente o índice de infiltração marginal nas interfaces das restaurações; • A resina quimicamente ativada Concise e as fluídas Aeliteflo e Natural Flow ocuparam uma posição intermediária com relação à infiltração marginal, com desempenho estatisticamente igual entre si e desfavoravelmente em relação ao Dyract AP; por outro lado, sobressaíram-se positivamente em comparação ao amálgama; • Não obstante o melhor comportamento apresentado pela resina composta modificada por poliácidos Dyract-AP, observou-se que nenhum material restaurador utilizado foi apto em impedir 100% a penetração da solução corante nas margens cervicais em cemento. / Marginal leakage is one of the clinical problems associated with posterior composite resin. Some clinics alternatives has been suggest, in attempt for reduce the defective of this material, specific in cementum cavities extended, where this problems could be increased. The aim of this study was to evaluated the marginal sealing effectiveness of different materials applied at the cervical third of class II cavities in association with composite resin (sandwich technique). Microleakage at the cement/material interface was measured. M.O.D. cavities with cervical margin extended below the cement-enamel-junction was made at 60 human non carie premolars, that was distributed in groups of 10 elements, ending up at 5 groups as follow: Control group – at each tooth, Scotchbond MP / Z-100; Group 1 – Scotchbond MP (Concise) / Concise / Scotchbond MP Z-100; Group 2 – Alpha Bond / Natural Flow / Scotchbond MP Z-100 Group 3 – One step / Aeliteflo / Scotchbond MP Z-100; Group 4 - Prime & Bond 2.1 / Dyract-AP / Scotchbond MP Z-100; Group 5 – Verniz copalite / Velvalloy / Scotchbond MP Z-100; Before the teeth were prepared and restored with the various materials, the apex were sealed with Scotchbond MP Z-100. After 48 hours the restorations were polished with Sof-Lex and were submitted to the mechanical cycling for 200 cycles of alternated loads, from 1 up to 17 kg. Than the teeth were stored in distilled water at 37ºC for 24 hours. After this the teeth were termocycled in a 2% methylene blue solution, corresponding to 180 cycles of 45 seconds each, at the temperatures of 5ºC, 37ºC, 55ºC. The specimens were stored again in methylene blue solution for 24 hours at 37 ºC. After this period, the teeth were embedded in acrylic bases and sectioned for the evaluation of the infiltration. Microleakage was determined by a qualitative analysis as showed the following conclusions: • The Velvalloy amalgam and the composite resin Z-100 used as the control group showed, respectively, the worst rates of the marginal leakage at the cement/restorative material margin; • There is statically significant between Dyract – AP and the others tested materials that showed lower rates of marginal microleakage; • Concise, Aeliteflo and Natural Flow resins has a medium position in the microleakage ranking, with the same statically performance, and, unfavorable when compared to Dyract-AP; although, it was better than the amalgam; • Although the Dyract-AP has the better performance, none of the testing materials avoid 100% microleakage at cervical margins in cementum.
28

Pricing Principles, Efficiency Concepts and Incentive Models in Swedish Transport Infrastructure Policy

Hasselgren, Björn January 2013 (has links)
In this article the shift of the Swedish goverment´s policies for the financing through taxation, fees and prices paid for the use of roads and railroads from 1945 until the 2010s is discussed. It is argued that the shift from a full-cost coverage principle to a short term social marginal cost principle can be seen in the light of the controversy between a Coasean and a Pigovian perspective. The Coasean perspective furthers an institutional view where organizations and dynamic development matters while the Pigovian perspective furthers a welfare economic equilibrium view where organizations are less focused. It is argued that the shift in policies coincided with less interest and focus on the organizational perspective and incentives for organizational efficiency, which can be seen in the public documents from the time. The government seems to have been guided by a mar ket failure stance since the 1970s which has motivated growing intervention, following a mar ket-economy stance in the first 25 years after the nationalization of roads and railroads. A current opening in transport infrastructure policies with more room for alternative financing, user charges and fees might, even though also consistent with short term social marginal cost principles, signal a revival of a perspective more in line with the Coasean view. / <p>QC 20130614</p>
29

Population patterns of hair zinc, dietary and socio-demographic determinants

Vaghri, Ziba 05 1900 (has links)
Marginal zinc deficiency (MZD) exists in children of industrialized societies and can impair growth and development. Presently there are no data available on its global prevalence. It is believed that MZD is one of the most common hidden deficiencies throughout the world. This is partly because of the lack of sensitivity and specificity of serum zinc, the most commonly used biomarker of zinc status, to detect MZD. This deficiency in children is always accompanied by a decrease in hair zinc. Although in research settings hair zinc is a recognized biomarker of MZD in children, health practitioners do not presently use it. These cross-sectional studies were designed to examine the hair zinc status of preschoolers in Vancouver. They also aimed at exploring some dietary and non-dietary factors associated with hair zinc status in an attempt to construct and validate a screening tool for detection of MZD. Our first study indicated a mean hair zinc of 75��30 ��g/g, with 46% below the cutoff (<70��g/g) for a group (n=87) of low-income preschoolers (Chapter II). Among these children we observed negative associations between the hair zinc and consumption of dairy (R�� =0.09, P=0 .01) and milk (R�� =0.08, P=0.01), being described as "often sick" (R�� =0.55, P=0 .00) and "eating unhealthy" (R�� =0.16 P=0.00), and prolonged breastfeeding (R�� =0.11, P=0.01). Our citywide survey (n=719) indicated a mean hair zinc of 116��43 ��g/g with 17% below the cutoff (Chapter III). Logistic regression analysis indicated sex, age, maternal education, the number of adults at home, consumption frequency of milk, "scores of activity level", "being described as frequently sick" and "taking supplements containing iron" as the significant predictors of hair zinc status. However, the final model had 16% sensitivity while having 98 .3% specificity, indicating its lack of usefulness as a screening tool. Our study provides important information on the hair zinc status of Vancouver preschoolers. Although we did not accomplish our primary goal of constructing and validating a screening tool, we did identify some factors in children and their environment associated with hair zinc, which may help in better understanding of hair zinc as a biomarker of MZD.
30

The doctrine of zero marginal productivity in agriculture in underdeveloped countries.

Abdulai, Yesufu S. M. January 1968 (has links)
No description available.

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