The diversity of choices we have to make everyday influence our environment and ourselves in more ways than most of us realise. Anthropogenic substances, such as flame retardants, date back as early as 450 BC when the Egyptians used alum to reduce flammability. The increasing demand for new articles has led to an increased production of chemical substances, for which many are commercially produced without complete knowledge on properties such as persistence, bioaccumulation and toxicology (PBT). Commercial compounds may be properly tested and denominated as “safe” regarding PBT properties, but their degradation products and/or metabolites may cause environmental impact. The availability of uniform and accurate data for prediction of persistence is of key importance for the understanding of chemical fate. A method to determine the susceptibility of chemicals to undergo oxidation in water has been developed and applied on several organohalogens, including PBDEs and OH-PBDEs. The method was used to determine reaction rates and the group of OH-PBDEs were subsequently subjected to photolysis by use of UV-light. Hence, susceptibility to undergo both oxidation and photolysis for the OH-PBDEs were investigated and compared to previously reported degradation rates on PBDEs. As a final step in promoting the prediction of persistence, Quantitative structure-property relationship (QSPR) models were performed on a set of compounds which had undergone photolytic degradation under similar conditions. The QSPRs were used as a preliminary step in predicting photolysis half-lives for chemical substances and to determine which physicochemical descriptors are of greatest importance thereof. This thesis presents the possibility of performing and assessing oxidation transformations on compounds of low and high water solubility, photolysis transformations in various media and using obtained data to predict behaviour via QSPR models, to promote predictions of persistence.

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Gerald Finzi (1901-1956) was an excellent English composer in the twentieth century. He has devoted his whole life to popularize British music and preserve literature. In the songbook Oh Fair to See, Finzi¡¦s wife and son collected seven songs which he had composed but have never published since 1921 to 1956. This study is to discover the close connection between literature and music by analyzing the lyrics and music of these songs. This study mainly contains four parts: the biographical life about Gerald Finzi, the characteristics of Finzi¡¦s art songs, the composing background of Oh Fair to See, and analysis of these songs. Each song shows Finzi¡¦s intuitive sense of blending words and sounds. Finzi employed a wide variety of figures both in the vocal phrases and in the accompaniment with an alternate and extensive use of tonal and model scale, which shows Finzi¡¦s creation that has great combination of music and poetry.

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Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

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INTRODUCTION: The incidence of pediatric nephrolithiasis (kidney stones) has been increasing over the past several years. While environmental factors, such as poor fluid intake, high-salt diet, and obesity, can play a role, underlying metabolic factors account for at least one-third of cases of nephrolithiasis. Nephrolithiasis and related disorders, such as nephrocalcinosis and hypercalciuria, can lead to long-term kidney problems, including renal scarring, acute and chronic kidney disease, decreased renal function, or end-stage renal disease. The best treatment is prevention and is best guided by knowing the underlying cause. The majority of kidney stones are primarily comprised of calcium, and abnormal calcium metabolism and regulation can lead to nephrolithiasis, nephrocalcinosis, and hypercalciuria. Vitamin D is an important factor in calcium regulation in the body. The physiologically active form of vitamin D is 1α,25-dihydroxyvitamin D (1,25(OH)2D), which increases serum calcium by stimulating intestinal absorption of calcium, increasing renal calcium reabsorption, and mobilizing calcium from bone. Excess 1,25(OH)2D has been shown to be associated with hyperabsorption of calcium in the intestine, nephrolithiasis, hypercalcemia, and hypercalciuria. Production of 1,25(OH)2D requires hydroxylation of 25-hydroxyvitamin D by the kidney enzyme 1α-hydroxylase, which is regulated in turn by serum calcium, parathyroid hormone (PTH), and by 1,25(OH)2D itself. Tight control of 1,25(OH)2D levels is maintained in part by the breakdown of 1,25(OH)2D by the enzyme 24-hydroxylase, which is encoded by the gene CYP24A1. In the past few years, CYP24A1 mutations leading to decreased activity of 24-hydroxylase have been implicated in some cases of idiopathic infantile hypercalcemia as well as nephrolithiasis, nephrocalcinosis, and hypercalciuria. The prevalence of 24-hydroxylase deficiency is not known, and the spectrum of its clinical manifestations is not yet fully understood. Our study aims to describe the clinical characteristics of patients with laboratory findings suggestive of 24-hydroxylase deficiency, specifically high-normal or elevated serum 1,25(OH)2D. We aimed to determine the prevalence of elevated 1,25(OH)2D among pediatric patients with nephrolithiasis, and to compare clinical outcomes and biochemical findings in patients with normal versus elevated 1,25(OH)2D. PATIENTS AND METHODS: This study was a retrospective chart review. To determine the prevalence of high-normal (56-75 pg/mL) and high (>75 pg/mL) serum 1,25(OH)2D, we reviewed electronic medical records of patients seen in the Boston Children's Hospital Stone Clinic. We identified 346 patients who were evaluated for nephrolithiasis, were under 18 years of age at the time of presentation, and had at least one measurement of 1,25(OH)2D. Patients were classified based on their highest measured level of 1,25(OH)2D. To determine the clinical characteristics of patients with elevated 1,25(OH)2D, we reviewed clinical records and laboratory data of patients at Boston Children's Hospital with a diagnosis of nephrolithiasis, nephrocalcinosis, or hypercalciuria. We identified 83 patients who met our inclusion criteria: age of onset <18 years, at least one measurement of 1,25(OH)2D, and a pre-treatment urine solute analysis. Data collected included demographic information, diagnoses, family history of kidney disease, treatments, laboratory data, and urine solute analyses. We compared findings in patients with normal 1,25(OH)2D (≤55 pg/mL) versus elevated 1,25(OH)2D (>55 pg/mL). RESULTS: Of 346 children with nephrolithiasis in whom 1,25(OH)2D was measured, 100 (28.9%) had high 1,25(OH)2D, and an additional 120 (34.7%) had high-normal 1,25(OH)2D. To determine the clinical characteristics of elevated 1,25(OH)2D, we analyzed the data of 40 patients with normal 1,25(OH)2D and 43 patients with elevated 1,25(OH)2D who had a history of nephrolithiasis, nephrocalcinosis, or hypercalciuria. Seventy-five children had nephrolithiasis, and 25/37 (67.6%) of children with elevated 1,25(OH)2D had a recurrence of nephrolithiasis, compared to only 9/38 (23.7%) of children with normal 1,25(OH)2D (p < .001). Urine calcium/creatinine ratio did not differ between the two groups. However, linear regression analysis showed an association between 1,25(OH)2D levels and urine calcium/creatinine ratio. Important secondary findings included a younger age of onset, higher serum 25-hydroxyvitamin D, and lower parathyroid hormone levels in patients with elevated 1,25(OH)2D. CONCLUSIONS: Important clinical findings of this study were the increased rate of recurrence and the younger age of onset in patients with elevated 1,25(OH)2D. While we recognize that mutations in CYP24A1 do not account for the majority of cases of elevated 1,25(OH)2D, we do advocate for special consideration for these patients. In the absence of a commercially-available assay for 24-hydroxylase activity, children with nephrolithiasis, nephrocalcinosis, or hypercalciuria and elevated 1,25(OH)2D should be closely monitored for recurrence or worsening of symptoms. Furthermore, we advise caution in the use of vitamin D repletion in at-risk patients.

The aim of this thesis was the first part of their work to process data on the number of foals born, import and export, trends in breeds of horses Shagya Arabian (Sh-a) and data horse's active Sh-a in the Czech Republic for the year 2014. The data were processed in Microsoft Office Excel 2007 and have created graphs. However, the number of foals born, it was found that most of them were born in 2009 and 2002. Import greatly outweighed exports, but in recent years also began to flourish and export. States Shagya-Arabians in the Czech Republic since 1994, continues to grow. In 2014, the Czech Republic 283 broodmares, 176 geldings, 142 mares, 133 stallions and 31 sire. In the second part of their work was the aim statistically evaluate data mares entered in the Stud book. This program was used Unistat 5.5. First, the statistical effect was studied by GLM and positive results have been used multiple comparisons by Tukey-B. It was found that on the basic colour has a highly significant influence line and family. Were examined influences on 4 basic body measurements (withers high tape, withers high rod, chest circumference, circumference of the cannon bone), where it was found that withers high tape, withers high rod, and chest circumference have a statistically significant effect of a family and line. The overall gain points is statistically highly significant influence lines and the number of ox 4th generation.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-07-27T14:20:48Z No. of bitstreams: 2 Dissertação - Aleckson Souto Silva - 2018.pdf: 4136117 bytes, checksum: 733a03156cbc3f72a6ac8bc4daff6b54 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-07-27T14:36:23Z (GMT) No. of bitstreams: 2 Dissertação - Aleckson Souto Silva - 2018.pdf: 4136117 bytes, checksum: 733a03156cbc3f72a6ac8bc4daff6b54 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-07-27T14:36:23Z (GMT). No. of bitstreams: 2 Dissertação - Aleckson Souto Silva - 2018.pdf: 4136117 bytes, checksum: 733a03156cbc3f72a6ac8bc4daff6b54 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-06-18 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The present work aims to the development of voltammetric sensors based on α-Ni(OH) 2 /GO and α- Ni(OH) 2 /rGO nanocomposites for detection and determination of uric acid, paracetamol and ascorbic acid by differential pulse voltammetry. For this, nanostructured nickel hydroxide stabilized in the alpha polymorphic form associated with graphene oxide (GO) or reduced graphene oxide (rGO) were synthesized and characterized. The method used for synthesis of α- Ni(OH) 2 was Tower’s modified, for oxidized graphite was that of Hummers and reduced graphene oxide was that of Stankovich. X-ray diffractometry, confocal Raman spectroscopy, cyclic voltammetry, transmission electron microscopy, infrared spectroscopy and thermogravimetric analysis were used to characterize the synthesized nanomaterials. The presence of graphene oxide and reduced graphene oxide with nickel hydroxide was confirmed by the results. The nickel hydroxide/graphene composites arouse great interest for the development of electrochemical sensors due to their good cost-effectiveness, biocompatibility and high catalytic effect. The thin films of α-Ni(OH) 2 /GO and α-Ni(OH) 2 /rGO showed better electrical properties compared to thin film of α-Ni (OH) 2 and it can be attributed to the increase in surface area and electrical conductivity. Through the differential pulse voltammetry, α-Ni(OH) 2 /GO and α-Ni(OH) 2 /rGO films presented good linear relationship between peak current and uric acid, ascorbic acid and paracetamol concentrations in the range concentration of 0.099 mmol.L -1 – 1.38 mmol.L -1 , with linear coefficients higher than 0.993 and detection limit lower than 2,645x10 -5 mol.L -1 for uric acid, 2,080x10 -5 mol. L -1 for ascorbic acid and 4.248x10 -5 mol. L -1 for paracetamol. / Este trabalho tem como objetivo o desenvolvimento de sensores voltamétricos baseados em nanocompósitos de α-Ni(OH) 2 /GO e α-Ni(OH) 2 /rGO para detecção e determinação de ácido úrico, paracetamol e ácido ascórbico através da voltametria de pulso diferencial. Para isso, hidróxido de níquel nanoestruturado e estabilizado na fase polimórfica alfa associado a óxido de grafeno (GO)ou óxido de grafeno reduzido (rGO) foram sintetizados e caracterizados. O método utilizado para a síntese do α-Ni(OH) 2 foi o de Tower modificado, o óxido de grafeno foi o de Hummers e o óxido de grafeno reduzido foi o de Stankovich. Para a caracterização dos nanomateriais sintetizados foram empregados a difratometria de raios-X, espectroscopia Raman confocal, voltametria cíclica, microscopia eletrônica de transmissão, espectroscopia no infravermelho e análises termogravimétricas. Sendo confirmados através dos resultados a presença de óxido de grafeno e óxido de grafeno reduzido junto ao hidróxido de níquel. Os compósitos de hidróxido de níquel/grafeno despertam grande interesse para o desenvolvimento de sensores eletroquímicos, devido a sua boa relação custo-benefício, biocompatibilidade e alto efeito catalítico. Os filmes finos de α-Ni(OH) 2 /GO e α-Ni(OH) 2 /rGO apontaram melhores propriedades elétricas compara ao filme fino de α-Ni(OH) 2 podendo ser atribuído ao aumento da área superficial e aumento da condutividade elétrica. Através da voltametria de pulso diferencial os filmes α-Ni(OH) 2 /GO e α- Ni(OH) 2 /rGO apresentaram boa relação linear entre a corrente de pico e a concentração de ácido úrico, ácido ascórbico e paracetamol na faixa de concentração de 0,099 mmol.L -1 – 1,38 mmol.L -1 , com coeficientes lineares superiores a 0,993 e limite de detecção inferiores a 2,645x10 -5 mol.L -1 para o ácido úrico, 2,080x10 -5 mol.L -1 para o ácido ascórbico e 4,288x10 -5 para o paracetamol.

Objectives: To assess the association between serum 25(OH)D and body mass index (BMI) in pre- and early-adolescents and to determine whether this association varies by demographic/clinical characteristics. Methods: Vitamin D status was determined using serum 25(OH)D in healthy pre- and early adolescents in Pittsburgh, PA (deficiency=/mL, insufficiency=12-/mL, sufficiency=≥20 ng/mL). Adiposity was quantified using BMI percentile (normal=<85th, overweight=>85th-95th, obese=>95th). The relationship between serum 25(OH)D and adiposity was assessed in the total population and after stratification by gender, race, Fitzpatrick skin type, age, and Tanner stage. Results: 294 children (mean age 10.2 + 2.1 years; 60% African American; median serum 25(OH)D=27.0 ng/mL) were studied. Serum 25(OH)D was significantly lower in obese (n=72) vs. overweight (n=48) and normal weight (n=171) participants at 23.6, 29.5, and 28.2 ng/mL, respectively; p=0.015. This trend remained significant for early adolescents but did not differ after stratification by other demographic/clinical characteristics. A significant negative correlation was found between BMI and serum 25(OH)D (r = -0.315; p=0.000). Regression analysis predicted that 25% of the variance in serum 25(OH)D levels was attributed to BMI, gender, race, skin type, age, pubertal status, daily vitamin D and calcium intake, sun exposure, and sunscreen use, with Tanner stage being the only significant independent predictor. Conclusions: A significant inverse association between serum 25(OH)D and adiposity was observed in a population of pre- and early adolescents. This relationship was stronger in early adolescents. A meta-analysis to further explore this association in pediatric populations is warranted.