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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.
641

Densidade energética: relação com variáveis demográficas, de estilo de vida, nutricionais e socioeconômicas em amostra representativa da população adulta do município de São Paulo / Energy density: association with demographic, lifestyle, nutritional and socioeconomic variables in a representative sample of adult population in the city of São Paulo.

Stella, Roberta Horschutz 05 September 2008 (has links)
Introdução - A densidade energética (DE), definida como a quantidade de energia por unidade de peso, é um importante fator na ingestão de alimentos e no valor calórico total da alimentação. Dessa forma, é uma característica da dieta que pode estar envolvida na qualidade da alimentação e no controle de peso. Objetivo - Analisar a relação entre a DE da dieta com variáveis demográficas, de estilo de vida, nutricionais e socioeconômicas em amostra representativa da população adulta do Município de São Paulo. Métodos - Foram utilizados dados secundários do projeto em Políticas Públicas, intitulado \"Inquérito de Saúde no Município de São Paulo - ISA-Capital\". Trata-se de um estudo transversal, de base populacional. O grupo de estudo foi composto por adultos, de ambos os sexos (N=710). O consumo alimentar foi medido através do método Recordatório de 24 horas. O consumo relatado foi transformado em energia e nutrientes com a utilização do software Nutrition Data System (NDS). A DE da dieta foi estimada através de três métodos: 1- inclusão de todos os alimentos e bebidas; 2- inclusão de todos os alimentos e bebidas calóricas que contenham, no mínimo, 5 Kcal/100g; 3- inclusão de todos os alimentos e exclusão de todas as bebidas. Para avaliar as relações entre a densidade energética da dieta e as variáveis demográficas, de estilo de vida, e socioeconômicas de interesse, foi utilizada a análise de regressão linear múltipla. Resultados: A população estudada foi composta por 56,7% de mulheres, 61,1% da etnia branca e 60,1% com situação conjugal unida/casada. A idade mínima foi de 20 anos e a idade máxima de 59 anos, com média de 36,2 anos. Os valores médios encontrados para a DE1, DE2 e DE3 foram 1,32 kcal/g (EP=0,01), 1,35 kcal/g (EP=0,01) e 1,95 kcal/g (EP=0,02), respectivamente. No modelo múltiplo, a escolaridade do indivíduo e a situação de trabalho \"em atividade\" associaram-se inversamente, ajustado por etnia para DE1 e DE2. Para DE3, foi verificada associação direta para etnia \"outras\" e inversa para hábito de fumar \"ex-fumante\". Conclusões: As médias de densidade energética encontradas no estudo mostraram-se superiores aos poucos estudos populacionais Resumo disponíveis. Os resultados apontados pelos diferentes métodos de cálculo da densidade energética sugerem que a contribuição dos líquidos não pode ser subestimada. / Introduction: Energy density (ED), defined as the amount of energy per unit weight, is a major factor related to food intake and total dietary energy. It is a dietary component that may be involved with diet quality and weight control. Objective: To assess the association between dietary ED and demographic, lifestyle, nutritional and socioeconomic variables in a representative sample of adult population in the city of São Paulo. Methods: A population-based, cross-sectional study was conducted based on secondary data from the Public Policies project, \"Health Survey in the City of São Paulo - ISA-Capital\". The study sample comprised both male and female adults (N=710). Food intake was measured using a 24-hour food recall. The reported intake was converted into energy and nutrients by the Nutrition Data System (NDS) program. Dietary ED was estimated through three different approaches: 1- inclusion of all foods and beverages; 2- inclusion of all energetic foods and beverages with a calorie content of at least 5 kcal/100 g; 3- inclusion of all foods and exclusion of all beverages. A multiple linear regression analysis was carried out to assess the associations between dietary ED and the study variables. Results: In the sample studied, 56.7% were women, 61.1% were White and 60.1% were either married or living with a partner. Mean age was 36.2 years, ranging between 20 and 59 years. Mean ED1, ED2 and ED3 were 1.32 kcal/g (SE=0.01), 1.35 kcal/g (SE=0.01) and 1.95 kcal/g (SE=0.02), respectively. In the multiple regression analysis, schooling and \"active\" working status were inversely associated, after adjusting for ethnicity, with ED1 and ED2. For ED3, there was found a direct association with \"other\" ethnicity and an inverse association with \"former smoking\". Conclusions: Mean energy densities found in the study were higher than those reported in few other population-based studies available. The results obtained through the different approaches for ED estimation indicate that the contribution of liquids should not be underestimated.
642

Efeito da imunização passiva com fragmentos variáveis de cadeia única anti-LDL eletronegativa na aterosclerose experimental / Passive immunization effect with anti-electronegative LDL single chain fragments variable in experimental atherosclerosis

Cavalcante, Marcela Frota 04 October 2012 (has links)
A aterosclerose é uma doença crônico-inflamatória multifatorial com o envolvimento do sistema imunológico, sendo o resultado da interação de diferentes elementos celulares. A lipoproteína de baixa densidade eletronegativa [LDL(-)], capaz de induzir o acúmulo de ésteres de colesterol em macrófagos e a subsequente formação de células espumosas, desempenha um papel-chave na doença. Anticorpos recombinantes têm sido gerados nas últimas décadas, como o scFv (single chain fragment variable), com o intuito de serem utilizados como uma novas alternativas de prevenção para o surgimento da lesão. Diante do papel da LDL(-) na aterosclerose, este projeto avaliou o efeito da imunização passiva de camundongos LDLr-/-- com scFv anti-LDL(-) em solução e scFv anti-LDL(-) conjugado a nanocápsulas, em relação ao desenvolvimento e progressão da aterosclerose. Após obtenção do scFv e sua conjugação à nanocápsulas (NC-scFv), ensaios in vitro determinaram a diminuição da captação de LDL(-) em macrófagos tratados com o scFv 2C7 anti-LDL(-) em solução. No entanto, o tratamento com NC-scFv promoveu o aumento da internalização de LDL(-) em relação ao controle, possivelmente por um mecanismo de endocitose mediada por receptor específico. Estudos in vivo determinaram que camundongos LDLr-/- com idade entre 2 e 3 meses tratados com o scFv em solução apresentaram menor área de lesão aterosclerótica (p<0,05) quando comparados ao controle e que animais com 3 a 4 meses de idade tratados com NC-scFv demonstraram uma tendência à diminuição do mesmo parâmetro. Na análise da expressão de proteínas por imunohistoquímica, ambos os grupos tratados com scFv 2C7 anti-LDL(-) em solução e NC-scFv demostraram redução significativa da expressão dos receptores CD14 e TLR-4 no local da lesão. Esse achado tem grande importância, uma vez que dados da literatura apresentam ambos os receptores como possíveis candidatos ao reconhecimento da LDL(-). Diante dos dados obtidos, o estudo evidenciou a eficácia do scFv 2C7 anti-LDL(-) em solução e da formulação NC-scFv no contexto da aterosclerose, possibilitando a sua utilização como estratégias terapêuticas na intervenção precoce para prevenir o desenvolvimento e a progressão da doença. / Atherosclerosis is a chronic inflammatory multifactorial disease related to the immune system and being the result of interaction of different cellular elements. The electronegative LDL, since the changes undergone by this particle are able to induce the accumulation of cholesterol esters in macrophages and the subsequent formation of foam cells, plays a key role in atherosclerosis. Recombinant antibodies have been generated in recent decades, such as scFv, (single chain fragment variable), and they may be used as a new alternative treatment for atherosclerosis treatment or prevention. Considering the role of LDL(-) in atherosclerosis, this project evaluated the effects of the treatment with anti-LDL(-) scFv 2C7 solution and anti-LDL(-) scFv conjugated to nanocapsules as a passive immunization strategy on atherosclerosis induced in LDL receptor knockout mice. After obtaining the anti-LDL(-) scFv 2C7 solution and its conjugation to nanocapsules (NC-scFv), in vitro tests led to the decrease in LDL(-) uptake in macrophages treated with anti-LDL(-) scFv 2C7. However, the treatment of macrophages with NC-scFv promoted increased internalization of LDL(-) as compared to control, possibly due to a mechanism of specific receptor-mediated endocytosis. In vivo studies have determined that LDLR-/- mice aged 2 and 3 months treated with anti-LDL(-) scFv 2C7 solution showed less atherosclerotic lesion area (p <0.05) compared to control and animals aged 3 to 4 months treated with NC-scFv showed a decreasing tendency of the same parameter. In the analysis of protein expression by immunohistochemistry, both groups treated with anti-LDL(-) scFv 2C7 solution and NC-scFv showed significant reduction of CD14 receptor expression and TLR-4 at the lesion site. This finding is of great importance, since the literature has both receptors as candidates for recognition of the LDL(-). From the data obtained, the study demonstrated the efficacy of treatments anti-LDL(-) scFv 2C7 in solution and NC-scFv in the context of atherosclerosis, enabling their use as therapeutic strategies in the early intervention to prevent the development and progression of the disease.
643

Caracterização anatômica e física - por densitometria de raios X - de colmos de Dendrocalamus asper Backer, Dendrocalamus latiflorus Munro e Guadua angustifolia Kunth / Anatomical and physical characterization - by X-ray densitometry - of culms of Dendrocalamus asper Backer, Dendrocalamus latiflorus Munro and Guadua angustifolia Kunth

Geroto, Priscila Garcia 23 May 2014 (has links)
A viabilidade da produção, do manejo e da utilização dos colmos de bambu no Brasil, em relação às árvores de espécies florestais de eucaliptos e pinus, entre outras, foi a principal motivadora do presente trabalho. Com esse objetivo foram caracterizados os colmos de 3 espécies de bambu, consideradas prioritárias pelo INBAR, a saber Dendrocalamus asper, D. latiflorus e Guadua angustifolia da Coleção de Bambus da Área Experimental Agrícola do Departamento de Engenharia Mecânica, Campus da UNESP, Bauru, SP. Amostras dos colmos das 3 espécies, coletadas através de método não destrutivo, foram caracterizadas em relação à estrutura anatômica macro e microscópica. Por meio da técnica de densitometria de raios X , a densidade aparente ao longo da espessura dos colmos foi determinada, e os perfis de densidade radial foram plotados em gráficos. Os resultados das análises laboratoriais evidenciaram que (i) as 3 espécies apresentam uma estrutura anatômica macro e microscópica que permite a sua identificação taxonômica e caracterização tecnológica, em relação aos tecidos de parênquima, feixes vasculares e bainha de fibras; (ii) a variação da estrutura anatômica e da densidade aparente ao longo da espessura dos colmos, relacionadas com a porcentagem e dimensões dos 3 elementos anatômicos, possibilita a sua caracterização em 3 camadas, sendo que as camadas interna e intermediária mostraram maiores diferenças em relação à externa; (iii) o modelo de variação das dimensões das fibras e da densidade aparente indicou um aumento dos dois parâmetros no sentido da camada interna para a externa dos colmos; (iv) não foi observado, para nenhuma das 3 espécies, um padrão de distinção entre a dimensão de fibras de colmos mais jovens e adultos; (v) os tipos dos feixes vasculares dos colmos das 3 espécies de bambu corresponderam aos descritos na literatura e, ainda, (vi) não foram encontradas referências da aplicação da densitometria de raios X na caracterização dos perfis de densidade aparente dos colmos de bambu e sua relação com a sua estrutura anatômica. O presente trabalho discute a aplicação dos seus resultados em relação a (i) influência das variações climáticas do ano de formação na espessura e anatomia dos colmos e (ii) aplicação tecnológica dos colmos pela análise dos perfis de densidade aparente e composição anatômica. / The feasibility of the production, management and utilization of bamboo culms in Brazil, in relation to forest species like eucalyptus, and pine trees , was the main motivator of the present work. Considering this purpose, culms of 3 bamboo species, considered priorities by INBAR, were characterized; namely Dendrocalamus asper, D. latiflorus Guadua angustifolia, all from the \"Collection of Bamboos\" owned by the Agricultural Experimental Area of the Department of Mechanical Engineering, from UNESP, Bauru Campus, SP. Samples from the 3 species stems, acquired through a non-destructive method, were characterized as for macroscopic and microscopic anatomical structure. Through the technique of X-ray densitometry, the apparent density along the stems\' thickness was determined, and the radial density profiles were plotted on. The laboratory tests results showed that (i) 3 species have macro and microscopic anatomical structures that allows its taxonomic identification and technological characterization, regarding parenchyma tissues, vascular bundles and fibers sheath; (ii) the variation of the anatomical structure and apparent density across the culm\'s cross plane, related with percentage and dimensions of the 3 anatomical elements, enables its characterization in three layers, of which the inner and intermediate layers showed major differences relative to the external one; (iii) the variation model of fiber dimensions and apparent density indicated an inner-outer layer oriented increase of these parameters; (iv) Was not observed, for any of the 3 species, a pattern of distinction between the culms fibers size regarding younger, or older individuals; (v) the bamboo vascular bundles types of the 3 species corresponded to those described in the literature and, moreover, (vi) there were no references found on the application of X-ray densitometry in the characterization of bamboo stems apparent density profiles and its relation to its anatomical structure. This study discusses the application of it\'s results in relation to (i) the growth year climatic variations influence on the thickness and anatomy of culms and (ii) the technological application of the stems by means of the apparent density and anatomical composition analysis.
644

A multi-scale study of bone mineralization and bone quality in adolescent idiopathic scoliosis / CUHK electronic theses & dissertations collection

January 2015 (has links)
Introduction. The etiology of adolescent idiopathic scoliosis (AIS) is largely unknown. AIS was well-documented to be associated with low bone mineral density (BMD) and abnormal bone quality. We hypothesized that bone matrix mineralization is abnormally low in AIS and that the abnormality could lead to the observed osteopenia and abnormal bone quality that might contribute to the etiopathogenesis of AIS. / Objectives. 1. To verify the abnormal bone mass and bone quality in AIS Vs normal matched controls 2. To study the bone matrix mineralization status, micro-architecture and mechanical property in AIS Vs controls 3. To study the cellular and molecular characterization of bone formation and resorption in AIS Vs controls 4. To study the possible association of abnormal bone quality with the curve progression / Methods. 1. The case-control study in Chapter 3 included 257 AIS and 187 age- and gender-matched normal controls. BMD and bone quality were measured with dual-energy X-ray absorptiometry (DXA) and high-resolution peripheral quantitative computed tomography (HR-pQCT) in vivo. 2. Chapter 4 studied iliac crest bone biopsies from 28 AIS and 9 controls. Bone mineral status was measured with DXA, micro-computed tomography (micro-CT) and energy dispersive X-ray spectroscopy; bone micro-architecture and mechanical property were measured with micro-CT, individual trabeculae segmentation analysis and finite element analysis (FEA). 3. Chapter 5 included 46 AIS and 23 controls. The mRNA expression of the bone tissue and primary osteoblastic and osteoclastic activities related to bone mineralization were studied. 4. Chapter 6 included 82 AIS patients. Bone quality was measured with HR-pQCT in vivo at baseline. Comparison was made between the stable and the progressive patients followed for more than 1.5 years after skeletal maturity. / Results. 1. In Chapter 3, both osteopenic and non-osteopenic AIS had lower areal BMD (aBMD) and trabecular and cortical volumetric BMD (vBMD) than their matched normal controls, with the non-osteopenic AIS reaching statistical significance (P<0.05). Osteopenic AIS had larger cortical perimeter and trabecular area than the osteopenic controls after adjustments of confounding factors (P<0.05); non-osteopenic AIS had significantly lower cortical area, thickness and vBMD than the non-osteopenic controls (P<0.05), and marginally significant cortical area and thickness after adjustments. 2. In Chapter 4, AIS had lower bone calcium content (Ca/C ratio) in trabecular bone than controls (P<0.05); moreover, AIS had significantly lower trabeculae rod number and thickness and mechanical property (P<0.05). Osteopenic AIS had significantly lower rod and plate micro-architecture (P<0.05) and 11.3% of decline of FEA mechanical property than non-osteopenic AIS. 3. In Chapter 5, AIS had lower expression of osteogenic markers (ALP and RUNX2) (P=0.009-0.132) and higher expression of extracellular matrix markers (COL1 and BGLAP) (P =0.109-0.132) in bone formation, and higher expression of bone resorption markers (TRAP and CTSK) (P =0.045-0.100). AIS also showed lower osteogenic differentiation potential and calcium nodule formation ability than controls. Within the subgroups, osteopenic AIS showed lower osteoblastic differentiation (P=0.009) and 41.8% decline of calcium formation abilities (P =0.186). The primary osteoblasts from the osteopenic AIS had higher pro-osteoclastogenic potential (P =0.034) and higher osteoclastogenic differentiation potential on osteoclasts. 4. In Chapter 6, progressive AIS had significantly lower aBMD, total vBMD and lower cortical area and thickness after adjustments (P<0.05). The predictive model showed that bone quality model was more predictive than the aBMD model which was more predictive than the basic model on curve progression. / Discussions The present study verified all the AIS had lower BMD and abnormal bone quality. It provided a direct evidence of lower calcium content in AIS which might contribute to the observed lower BMD. Therefore, these abnormalities in AIS could represent a spectrum of severity which is labeled as osteopenic or non-osteopenic with DXA and partly explained by the cellular and molecular studies. The longitudinal study showed AIS with poorer bone quality have significantly higher probability of curve progression. In summary, the present findings supported and confirmed our proposed hypothesis. / 引言:有研究提示AIS低骨量與骨質量異常與病因學有關。我們推測,AIS的骨基質礦化可能異常降低,進而導致低骨量和異常骨質量發生,這可能與AIS病因学有關。 / 目的:1. 驗證AIS的低骨量及骨質量異常 2. 调查AIS骨基質礦化、骨微結構和機械性能狀態 3. 研究AIS關於骨礦化的細胞分子功能 4. 探讨AIS骨質量與側彎進展間的關聯 / 方法:1. 通過雙能吸收儀和高分辨率外周定量CT比较低骨量和非低骨量AIS与其正常對照間骨密度和骨質量的差异 2. 通過雙能吸收儀、顯微CT和掃描電鏡與能量色散光譜儀檢測骨礦物質含量,及顯微CT、骨小梁個體分割和有限元分析法檢測骨微結構和力學性能,比較AIS和正常對照及AIS亞組間的差異。3. 通過檢測與骨礦化相關的mRNA,和原代成骨和破骨細胞培養,比較AIS和正常對照及AIS亞組間的差異。4. 通過高分辨率外周定量CT縱向隨診AIS患者,比較進展組和穩定組間骨質量差異。 / 結果:1. 低骨量和非低骨量AIS均比正常對照組骨密度和骨質量降低。2. AIS骨鈣含量降低,骨微結構和機械性能顯著異常。3. AIS骨形成標記物降低、骨吸收標記物升高,成骨分化潛能降低。低骨量AIS比非低骨量AIS成骨細胞分化能力降低和親破骨分化潛能升高。4. 側彎進展AIS骨密度和骨質量顯著異常。 / 討論:本研究結果支持我們的假設:AIS骨基質礦化異常,導致低骨量和異常骨質量,提示與AIS發病機理相關聯。 / Wang, Zhiwei. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 243-261). / Abstracts also in Chinese; appendixes includes Chinese. / Title from PDF title page (viewed on 09, September, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
645

A study of bone mineral profile: bone mineral density, bone turnover and genetic marker in AIS.

January 2000 (has links)
Cheung Siu-king. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves [103-113]). / Abstracts in English and Chinese. / ACKNOWLEDGMENT --- p.i / TABLE OF CONTENTS --- p.ii / LIST OF ABBREVIATIONS --- p.vi / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.ix / ABSTRACT (ENGLISH VERSION) --- p.x / ABSTRACT (CHINESE VERSION) --- p.xii / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1. --- ADOLESCENT IDIOPATHIC SCOLIOSIS --- p.1 / Chapter 1.1.1. --- prevalence and geographic patterns of ais --- p.1 / Chapter 1.1.2. --- CLINICAL ASPECTS OF AIS --- p.3 / Chapter 1.1.3. --- ETIOLOGY OF AIS --- p.8 / Chapter 1.2. --- OBJECTIVES OF THIS STUDY --- p.24 / Chapter 2. --- SUBJECTS AND METHODS --- p.25 / Chapter 2.1. --- STUDY DESIGN --- p.25 / Chapter 2.2. --- SUBJECTS RECRUITMENT --- p.25 / Chapter 2.2.1. --- ais subjects --- p.25 / Chapter 2.2.2. --- control subjects --- p.25 / Chapter 2.2.3. --- GROUPING ACCORDING TO THE CHRONOLOGICAL AGE --- p.26 / Chapter 2.2.4. --- informed Consent --- p.26 / Chapter 2.2.5. --- EVALUATION OF COBB'S ANGLE --- p.26 / Chapter 2.3. --- ANTHROPOMETRIC ASSESSMENTS --- p.26 / Chapter 2.4. --- BMD MEASUREMENTS --- p.28 / Chapter 2.4.1. --- measured by dexa --- p.28 / Chapter 2.4.2. --- measured by pqct --- p.30 / Chapter 2.5. --- BONE FORMATION MARKER : BALP --- p.32 / Chapter 2.5.1. --- SERUM COLLECTION --- p.32 / Chapter 2.5.2. --- ABBOTT METHODS FOR SERUM ALP ACTIVITY --- p.32 / Chapter 2.6. --- BONE RESORPTION MARKER : DPD --- p.34 / Chapter 2.6.1. --- PYRILINK-D KITS REAGENT --- p.34 / Chapter 2.6.2. --- CREATININE ASSAY --- p.34 / Chapter 2.7. --- GENETIC MARKER - POLYMORPHISM OF ESTROGEN RECEPTOR GENE --- p.38 / Chapter 2.7.1. --- DIGESTION OF PERIPHERAL BLOOD CELLS --- p.38 / Chapter 2.7.2. --- QUANTITATION OF DNA --- p.39 / Chapter 2.7.3. --- CONFIRMATION OF INTEGRITY OF DNA --- p.39 / Chapter 2.7.4. --- POLYMERASE CHAIN REACTION (PCR) --- p.39 / Chapter 2.7.5. --- REACTION BUFFER --- p.39 / Chapter 2.8. --- STATISTICS --- p.45 / Chapter 3. --- RESULTS --- p.46 / Chapter 3 .1 --- SUBJECT DISTRIBUTION OF AIS AND NORMAL CONTROL --- p.46 / Chapter 3.1.1. --- "mean ages of menarche, breast development and pubic hair development" --- p.47 / Chapter 3.1.2. --- "PUBERTAL STATUES OF DIFFERENT AGE GROUPS EVALUATED BY MENARCHE, BREAST DEVELOPMENT AND PUBIC HAIR DEVELOPMENT" --- p.48 / Chapter 3.2. --- ANTHROPOMETRIC ASSESSMENTS --- p.49 / Chapter 3.2.1. --- OVERALL REVIEW OF ANTHROPOMETRIC ASSESSMENTS --- p.49 / Chapter 3.2.2. --- ANTHROPOMETRIC ASSESSMENTS ACCORDING TO THE CHRONOLOGICAL AGE --- p.50 / Chapter 3.3. --- BMD PROFILE OF AIS PATIENTS --- p.51 / Chapter 3.3.1. --- ABMD MEASURED BY DEXA (OVERALL REVIEW) --- p.51 / Chapter 3.3.2. --- ABMD IN DIFFERENT AGE GROUPS --- p.52 / Chapter 3.3.3. --- VBMD MEASURED BY PQCT (OVERALL REVIEW) --- p.52 / Chapter 3.3.4. --- VBMD IN DIFFERENT AGE GROUPS --- p.53 / Chapter 3.3.5. --- PREVALENCE OF OSTEOPENIA IN AIS PATIENTS --- p.53 / Chapter 3.3.6. --- SYMMETRY OF BILATERAL PROXIMAL FEMUR AND DISTAL TIBIA … --- p.54 / Chapter 3.3.7. --- CORRELATION OF ABMD AND VBMD WITH ANTHROPOMETRIC PARAMETERS AND SPINAL DEFORMITY --- p.54 / Chapter 3.4. --- BONE FORMATION MARKER- BALP --- p.55 / Chapter 3.5. --- BONE RESORPTION MARKER -DPD --- p.56 / Chapter 3.6. --- GENETIC MARKER -ESTROGEN RECEPTOR GENE --- p.57 / Chapter 4 --- DISCUSSION…… --- p.84 / Chapter 4.1 --- BONE MINERAL DENSITY OF AIS PATIENTS --- p.84 / Chapter 4.2 --- ANTHROPOMETRIC MEASUREMENTS --- p.89 / Chapter 4.3 --- BONE BIOCHEMICAL TURNOVER MARKER --- p.91 / Chapter 4.4 --- GENETIC MARKER - ER GENE --- p.97 / Chapter 4.4.1 --- OSTEOPORTIC CANDIDATE GENE- ER GENE --- p.98 / Chapter 4.4.2 --- NO CORRELATION BETWEEN ER GENE AND AIS --- p.99 / Chapter 4.5 --- SUMMARY --- p.100 / Chapter 5. --- CONCLUSION --- p.101 / BIBLIOGRAPHY --- p.XIV / APPENDIX --- p.XXV
646

A study of Douglas-fir anatomical and mechanical properties and their interactions

Bawcombe, Jonathan January 2012 (has links)
Low embodied energy, ability to act as a carbon store and ease of recycling gives forest products an important role within a low carbon built environment. Almost 25 % of the coniferous resource within the South West of England is Douglas-fir, a species reputed for producing high quality timber. Despite this, the region is facing challenges in delivering the resources full potential, a contributing factor to which is a loss of knowledge regarding its quality. The aim of the work presented is to gain an improved understanding of the quality of Douglas-fir grown within the region, from the perspective of uses in structural applications, the factors which influence material quality and their interrelationships. Flexural modulus of elasticity, flexural and compressive strength were determined utilising small clear specimens derived from 1.3 and 8 m heights within 27 trees from six sites across the South West. Results showed a rise in the magnitude of properties with increasing cambial age, particularly so at younger ages. Differences in values were also recorded between stem heights and with rate of growth. These were however less than age related variations. Results compared favourably to those reported in other studies conducted on the species. Utilising SilviScan-3, anatomical properties including density, microfibril angle and cellular dimensions were measured. Significant variations were recorded with cambial age, and in some instances sampling height. The influence of growth rate on anatomical properties was small. Through statistical and composite modelling, microfibril angle was found to be strongly associated with changes in modulus of elasticity within juvenile wood. Within mature wood and for strength properties, density was the controlling factor. It was shown that a moderate proportion of variations in mechanical properties can be accounted for utilising visually identifiable wood characteristics. The new understanding that has been gained through this work presents opportunities for improved utilisation, the implementation of effective management practices and the development of more efficient visual grading techniques.
647

Beta thalassemia-induced osteoporosis: evaluating current and novel therapeutic options

Khullar, Natasha 03 November 2016 (has links)
Osteopenia and/or Osteoporosis (OOS) is becoming an increasingly prevalent chronic disease among Beta Thalassemia Major (BTM) patients, especially now that life expectancy in these patients has considerably improved through regular blood transfusions and iron chelation therapy. With several, complex genetic and acquired factors involved in its pathogenesis, coupled with the heterogeneity in the clinical response of BTM patients to different pharmacological agents, OOS has proven to be particularly difficult to treat. The great majority of treatment options currently available are not curative, but instead are aimed towards managing the symptoms and progression of the disease in patients. General preventative measures, such as iron chelation therapy and hormonal replacement therapy (HRT), are instrumental aspects of the treatment plan; however, the incredible complexity of OOS necessitates an individualized, multidisciplinary approach to management, with a principal therapy that is safe and effective in patients, and that is accompanied by these other supportive measures. This review, through a comprehensive analysis of current literature, includes data from randomized, placebo-controlled trials, double blind and observational clinical studies, and suggests optimal therapeutic interventions for first-line management of OOS. It also addresses treatment options for BTM patients in whom resistance to the recommended first-line therapy develops, or who display secondary endocrine conditions contributing to OOS. In addition to providing a current synopsis of OOS management and the potential of emerging treatment options, this analysis highlights some of the limitations of traditional therapies. In this way, the paper effectively illustrates the current status of TM-induced OOS; it describes what is or isn’t working, as well as underscores the diagnostic and therapeutic challenges continually faced by patients, researchers and clinicians.
648

Crystal structure prediction at high pressures : stability, superconductivity and superionicity

Nelson, Joseph Richard January 2017 (has links)
The physical and chemical properties of materials are intimately related to their underlying crystal structure: the detailed arrangement of atoms and chemical bonds within. This thesis uses computational methods to predict crystal structure, with a particular focus on structures and stable phases that emerge at high pressure. We explore three distinct systems. We first apply the ab initio random structure searching (AIRSS) technique and density functional theory (DFT) calculations to investigate the high-pressure behaviour of beryllium, magnesium and calcium difluorides. We find that beryllium fluoride is extensively polymorphic at low pressures, and predict two new phases for this compound - the silica moganite and CaCl$_2$ structures - to be stable over the wide pressure range 12-57 GPa. For magnesium fluoride, our results show that the orthorhombic `O-I' TiO$_2$ structure ($Pbca$, $Z=8$) is stable for this compound between 40 and 44 GPa. Our searches find no new phases at the static-lattice level for calcium difluoride between 0 and 70 GPa; however, a phase with $P\overline{6}2m$ symmetry is energetically close to stability over this pressure range, and our calculations predict that this phase is stabilised at high temperature. The $P\overline{6}2m$ structure exhibits an unstable phonon mode at large volumes which may signal a transition to a superionic state at high temperatures. The Group-II difluorides are isoelectronic to a number of other AB$_2$-type compounds such as SiO$_2$ and TiO$_2$, and we discuss our results in light of these similarities. Compressed hydrogen sulfide (H$_2$S) has recently attracted experimental and theoretical interest due to the observation of high-temperature superconductivity in this compound ($T_c$ = 203 K) at high pressure (155 GPa). We use the AIRSS technique and DFT calculations to determine the stable phases and chemical stoichiometries formed in the hydrogen-sulfur system as a function of pressure. We find that this system supports numerous stable compounds: H$_3$S, H$_7$S$_3$, H$_2$S, H$_3$S$_2$, H$_4$S$_3$, H$_2$S$_3$ and HS$_2$, at various pressures. Working as part of a collaboration, our predicted H$_3$S and H$_4$S$_3$ structures are shown to be consistent with XRD data for this system, with H$_4$S$_3$ identified as a major decomposition product of H$_2$S in the lead-up to the superconducting state. Calcium and oxygen are two elements of generally high terrestrial and cosmic abundance, and we explore structures of calcium peroxide (CaO$_2$) in the pressure range 0-200 GPa. Stable structures for CaO$_2$ with $C2/c$, $I4/mcm$ and $P2_1/c$ symmetries emerge at pressures below 40 GPa, which we find are thermodynamically stable against decomposition into CaO and O$_2$. The stability of CaO$_2$ with respect to decomposition increases with pressure, with peak stability occurring at the CaO B1-B2 phase transition at 65 GPa. Phonon calculations using the quasiharmonic approximation show that CaO$_2$ is a stable oxide of calcium at mantle temperatures and pressures, highlighting a possible role for CaO$_2$ in planetary geochemistry, as a mineral redox buffer. We sketch the phase diagram for CaO$_2$, and find at least five new stable phases in the pressure/temperature ranges 0 $\leq P\leq$ 60 GPa, 0 $\leq T\leq$ 600 K, including two new candidates for the zero-pressure ground state structure.
649

Parâmetros biofísicos, bioquímicos e imunohistoquímicos de fêmures de Rattus novergicus albinus em diferentes idades para padronização de valores de referência estática e dinâmica /

Coêlho, Juliana de Carvalho Apolinário. January 2013 (has links)
Orientador: Mário Jefferson Quirino Louzada / Coorientador: Maria Tereza Nunes / Banca: Keico Okino Nonaka / Banca: José Carlos Silva Camargo Filho / Banca: Ivania Garavello / Banca: João Cesar Bedran de Castro / Resumo: Neste estudo foram avaliadas características ósseas dos fêmures de ratos machos Wistar, em diferentes idades, provendo fundamentação científica para o desenvolvimento de estratégias e mecanismos de prevenção de doenças ósseas. Para tanto, realizou-se a determinação dos parâmetros do fêmur de Rattus novergicus albinus com 2, 4, 6, 12, 14, 16 e 20 meses de idade, utilizando densitometria óssea, ensaio mecânico, análises celulares, análise de volume ósseo percentual, espessura trabecular, número de trabéculas e separação trabecular obtidas por microtomografia computadorizada. Os parâmetros ósseos foram apresentados como média e erro padrão da média, submetidos à análise de variância - ANOVA e teste de Tukey com p<0,05 para comparação entre os grupos. Os resultados indicaram alterações relacionadas com a idade, demonstrando que a força máxima, a rigidez, o material mineral do fêmur, a densidade mineral óssea do colo e cabeça do fêmur, o volume ósseo percentual, a espessura trabecular e a separação entre as trabéculas da cabeça do fêmur apresentaram aumento significativo (p<0,05) aos 12 meses de idade em relação aos animais mais novos e uma diminuição significativa (p<0,05) aos 16 e 20 meses de idade em relação aos animais de 12 meses. Houve menor marcação de TRAP em relação a OC nos animais jovens e adultos (2 e 12 meses de idade). Com base nos achados deste estudo, pode-se concluir que há uma progressão das características ósseas de Rattus novergicus albinus, linhagem Wistar, machos, até 12 meses de idade e uma diminuição dos parâmetros ósseos aos 16 e 20 meses de idade / Abstract: We evaluated the femur bone characteristics of male Wistar rats at different ages, providing scientific basis for the development of strategies and meechanisms for the prevention of bone diseases. For that purpose the determination of the parameters of the femur Rattus novergicus albinus with 2, 4, 6, 12, 14, 16 and 20 months of age using bone densitometry, mechanical testing, cellular analysis, analysis of bone volume percentage, trabecular thickness, trabecular number, and trabecular separation obtained by computed microtomography. The bone parameters were presented as mean and standard error of mean, subjected to analysis of variance - ANOVA and Tukey test with p <0.05 for comparison between groups. The results indicate changes related to age, demonstrating that the maximum strength, the stiffness, the mineral material of the femur, the bone mineral density of the femoral lap and head, the bone volume percentage, the trabecular thickness and the separation between the trabecular of the femoral head, showed a significant increase (p<0,05) at 12 months of age compared to younger animals and a significant decrease (p<0,05) at 16 and 20 months of age compared to animals 12 months. There was a lower mark of TRAP in relation to OC in young and adult animals (2 and 12 months of age). Based on our findings, we can conclude that there is a progression of bone characteristics in Rattus norvegicus albinus, Wistar lineage, males, until 12 months of age and a decrease in bone parameters between 16 and 20 months of age / Doutor
650

Earth's Elastic and Density Structure from Diverse Seismological Observations

Moulik, Pritwiraj January 2016 (has links)
A large data set comprising normal-mode eigenfrequencies, quality factors and splitting functions, Earth's mass and moment of inertia, surface-wave phase anomalies and dispersion curves, body-wave arrivals and traveltime curves, as well as long-period waveforms is inverted to obtain the distribution of elastic properties, shear attenuation and density in the Earth's interior. We address three fundamental aspects of global seismology by reconciling and modeling data sets with several methodological improvements, such as accounting for radial and azimuthal anisotropy, development of better methods for crustal corrections, and devising novel regularization and parameterization schemes. In the first contribution, we incorporate normal-mode splitting functions with other seismological data sets to examine the variation of anisotropic shear-wave velocity in the Earth's mantle. Our preferred anisotropic model, S362ANI+M, has strong isotropic velocity anomalies in the transition zone while the anisotropy is restricted to the upper 300~km in the mantle. When radial anisotropy is allowed throughout the mantle, large-scale anisotropic patterns are observed in the lowermost mantle with v_SV > v_SH beneath Africa and South Pacific and v_SH > v_SV beneath several circum-Pacific regions. However, small improvements in fits to the data on adding anisotropy at depth leave the question open on whether large-scale radial anisotropy is required in the transition zone and in the lower mantle. We demonstrate the utility of mode-splitting data in reducing the tradeoffs between even-degree variations of isotropic velocity and anisotropy in the lowermost mantle. We then devise a methodology to detect seismological signatures of chemical heterogeneity using scaling relationships between shear velocity, density and compressional velocity in the Earth's mantle. Several features reported in earlier tomographic studies persist with the inclusion of new and larger data sets; anti-correlation between bulk-sound and shear velocities in the lowermost mantle as well as an increase in velocity scaling (nu=dlnv_S/dlnv_P) with depth in the lower mantle are found to be robust. Many spheroidal and toroidal modes are largely incompatible with perfect correlations between density and shear-velocity variations in the lowermost mantle. A way to fit concurrently the various data sets is by allowing independent density perturbations in the lowermost mantle. Our preferred joint model consists of denser-than-average anomalies (~1% peak-to-peak) at the base of the mantle roughly coincident with the low-velocity superplumes. The relative variation of shear velocity, density and compressional velocity in this study disfavors a purely thermal contribution to heterogeneity in the lowermost mantle. In the third contribution, we introduce an approach to construct a 1-D reference model that is consistent with crustal heterogeneities and various asphericities in the Earth's mantle. We demonstrate that the crust contributes substantially to fundamental-mode dispersion curves when the nonlinear effects of its thickness and velocity variations are taken into consideration. We apply appropriate crustal corrections and perform several iterations to converge to our preferred radial model NREM1D, which is anisotropic in the upper mantle and smooth across the 220-km discontinuity for all physical parameters. Radial anisotropy in the shallowest mantle, with a maximum at ~150~km depth, is required to fit global averages of fundamental-mode Rayleigh and Love wave dispersion (25--250s). NREM1D also predicts arrival times of major mantle and core phases in agreement (+/- 0.5s) with a recent isotropic velocity model that was optimized for earthquake location. The new reference Earth model NREM1D introduced here is easily extendable due to its modular construction as a linear combination of radial basis functions and can be used for earthquake location, spherical-earth normal mode calculations, and as a starting model in studies of lateral heterogeneity.

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