No description available.

Asset pricing models have been of interest since their origin in modern finance. The Capital Asset Pricing Model is a widely used tool and is one of the early developed asset pricing models in modern finance. There are continual improvements of this model with the evident multifactor models of Fama and French (2015), Carhart (1997) and the South African two – factor arbitrage pricing models of Van Rensburg (2002) and Laird-Smith et al. (2016). This research empirically investigates the performance of eight-different multi-factor asset pricing models in describing average portfolio returns in the South African Johannesburg Stock Exchange. We find that the Carhart (1997) four factor model comprising of the market factor, size factor, value factor and the momentum factor is the most parsimonious model and thus better explains the average portfolio returns in the South African JSE. This model is an improvement of the Fama and French (1992) three factor model. Additionally, we investigate the performance of the two factor Asset Pricing Theory (APT) model of Laird-Smith et al. (2016) and Van Rensburg (2002) that consists of the South African Financial Index (SAFI) and the South African Resources Index (SARI). We observe that the model performs better than the traditional CAPM that is widely used in industry. Adding the SAFI and the SARI to the six-factor model results in an eight-factor model that has a significant improvement in explaining average returns. The results indicate that the market factor, the South African Financial Index and the South African Resources Index (SARI) poorly explain each other but their linear combination improves the eight-factor asset pricing model in explaining average portfolio returns in the South African market. The eight – factor model comprises of the market, size, value, investment, profitability, momentum factors and the two South African indices namely, the South African Financials Index (SAFI) and the South African Resources Index (SARI).

Despite haemolytic anaemia being the main consequence of Babesia rossi infection in dogs, the bone marrow response has been reported to be mild in the face of severe anaemia. A similar finding has been described in falciparum malaria and has been ascribed to either a decreased production of erythroid precursors or an inability of erythroid precursors to respond to hormonal stimulus. Recently, more information has become available on the use of various reticulocyte indices in an attempt to describe and explain the underlying pathogenesis of various anaemias as their release describes the recent functional state of the bone marrow. The objective of this study was to compare the admission absolute reticulocyte count (ARC) and reticulocyte indices in dogs naturally infected with B. rossi with dogs suffering from immune-mediated haemolytic anaemia (IMHA), unrelated to babesiosis, as well as healthy control dogs. The ARC and reticulocyte indices were also evaluated in five experimentally B. rossi infected dogs throughout the disease course. This was a retrospective observational study looking at the records generated on a haematology analyser, the ADVIA 2120 (Siemens, Munich, Germany). The haematocrit (HCT), ARC and other reticulocyte indices for 103 dogs, naturally infected with B. rossi was compared to 16 dogs with IMHA and 14 control dogs. The experimentally infected dogs consisted of five purpose-bred beagles that were infected with high and low dose B. rossi parasite inoculum. Differences between groups were assessed using the Mann-Whitney U test, whereas the Friedman’s ANOVA was used to assess the change over time during the disease course in the experimentally infected dogs. The Wilcoxon Signed Ranks test was then used to determine the differences within the experimentally infected groups. The median (IQR) HCT for the Babesia (0.16 L/L; 0.12 – 0.27; P < 0.001) and IMHA (0.15 L/L; 0.12 – 0.17; P < 0.001) groups were significantly lower than the control group (0.52 L/L; 0.45 – 0.57). For the Babesia and IMHA groups the HCT did not differ significantly. Compared to the control group (42.1 x109/L; 33.8 – 62.6), the median (IQR) ARC was significantly higher in the Babesia (82.1 x109/L; 48.6 – 174.9; P = 0.006) and IMHA (256.7 x109/L; 79.0 – 436.9; P = 0.004) groups. The ARC was significantly lower in the Babesia group compared to the IMHA group (P = 0.011), despite no significant difference for HCT between groups. On day four of the experimentally infected group, approximately 24 – 48 hours after a peripheral parasitaemia was observed, there was a sudden decrease in the ARC to less than its value on day one, which was inappropriate for the degree of anaemia observed. The reticulocytes of B. rossi naturally infected dogs were larger and more hypochromic with a greater difference in cellular haemoglobin (CH) between reticulocytes and mature erythrocytes compared to the control group, whereas the reticulocytes of the experimentally infected dogs were smaller and more hypochromic than day one of infection. All reticulocyte indices demonstrated significant differences on day four compared to day one of the experimental study. The changes noted in the reticulocyte indices are postulated to be a contribution of anaemia of inflammation (AID), shift reticulocytosis and iron-restricted erythropoiesis. This study concludes that the regenerative response in dogs naturally infected with B. rossi is inappropriate, despite the severity of anaemia observed, compared to dogs with IMHA. Furthermore, the findings of the experimentally group may indicate a possible direct suppressive action of the Babesia parasite on the bone marrow during the time of parasitaemia, resulting in insufficient erythropoiesis. Similar findings have been reported in falciparum malaria and other factors will require further investigation. / Dissertation (MSc)--University of Pretoria, 2020. / Companion Animal Clinical Studies / MSc / Unrestricted

Neighborhoods are organic entities that are in a state of constant change and are driven by the specific context of the problem being investigated. The subsequent lack of consensus on a universal geographic definition for what constitutes a neighborhood can lead to biased interpretations of relationships between human activities and place. Further, while existing geographical information system software allows users to combine a range of geographic objects to generate regional units of analyses, their design does not explicitly assess how changing patterns, such as populations, impact the data expressed within them. This research develops an exploratory geographical information system framework that allows users to dynamically delineate neighborhoods based on user-specified characteristics. These include socioeconomic and similar measurements of neighborhood classification from information obtained from secondary data sources, including parcel data, land use/land cover information, and attribute data provided by the United States Postal Service. The proposed methodology creates custom geographies from readily available tract data obtained from various federal and state data repositories to produce indices. By allowing the user to dynamically weigh the combinations of variables used to define their neighborhood, this thesis introduces a solution to a common analytical problem in the discipline.

No description available.

Objectives. This study aimed to provide data on water intake from food and beverages of free-living adults in their natural environment, and investigate how this is affected by physiological, psychological, social and environmental factors. A further aim was to monitor the hydration status of free-living adults and relate this data to water intake. Methods The consumption of all food and beverages was recorded in a diary over three consecutive days by 80 healthy adults (40 males, 40 females), aged 18 to 65 years, who were instructed to continue their normal eating and drinking habits and lifestyles throughout the study. The data was analysed to determine total daily water intake and how this was affected by time of day, day of the week, presence of others, location of consumption, age and subjects mood. A further 20 healthy subjects (10 males, 10 females) repeated these procedures but also had blood samples taken for monitoring of blood indices (haemoglobin concentration, haematocrit, sodium concentration, and potassium concentration) and provided urine samples for the measurement of urine indices (volume, colour, specific gravity, osmolality and sodium, potassium, chloride, and creatinine concentrations). Results The total volume of water consumed by the 80 subjects was 2229  882 ml/day (mean  standard deviation). Females tended to consume more water than males (2402  827 ml/day vs 2056  911 ml/day, P = 0.079). Similar volumes were consumed by the additional 20 subjects in the hydration status study. Females appeared euhydrated; males appeared mild dehydrated, having a higher morning and 24-hour urine specific gravity and osmolality than females (P < 0.05, respectively). Conclusions The mean daily total volume of water consumed by females in this study was greater than the adequate intake value set by the European Food Safety Authority; for males it was lower. Females were euhydrated during the study but males tended to be mild dehydrated, reflecting their comparative water intakes.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

L’objectif général était d’évaluer la réponse du macrobenthos à la dynamique d’un herbier marin à Zostera noltii (colonisation, maturation, destruction, restauration), dans le Bassin d’Arcachon, une lagune du sud-ouest de la France. Quand l’herbier commence à se développer, la structure de la macrofaune diverge immédiatement entre habitats d’herbier et de sables nus, sans cependant que les indice biotiques testés (BENTIX, BOPA, AMBI) varient. De même, la population du bivalve dominant, la coque (Cerastoderma edule), souffre du développement de l’herbier. Sa communauté parasitaire (trématodes) est modifiée, sans que cela n’influe sur la dynamique des coques. A l’échelle du Bassin, le développement de l’herbier (considéré comme un signe de “bonne santé”) a été comparé à la santé de deux bivalves endogés dominants, la palourde japonaise (Ruditapes philippinarum) et la coque (C. edule), évaluée en termes de prévalence de maladie. Aucune corrélation n’existe entre le taux de recouvrement d’herbier et la prévalence de trois maladies (trématodiase, perkinsose, maladie du muscle marron). Entre 2002 et 2010, la surface d’herbier a diminué de 1/3. En termes de structure de communautés et d’espèces dominantes, peu de différences sont notées au sein de chaque année (entre les 12 stations) et entre années, indépendamment du déclin de l’herbier. Parmi les indicateurs biotiques, l’indice multivarié MISS est en adéquation avec la relative similarité de la structure de la macrofaune benthique entre les groupes discriminés par l’analyse MDS. En 2005, des activités de dragage dans le Bassin d’Arcachon ont abouti à l’enfouissement de 0,32 km2 d’herbier à Z. noltii. La structure du macrobenthos a été immédiatement modifiée sans retour à l’état initial sur les zones couvertes de sable. En revanche, le macrobenthos (endofaune) s’est rapidement rétabli dans les zones couvertes de vase alors que l’herbier n’a commencé à se développer qu’au bout de 5 ans après les travaux. Le dernier chapitre de cette thèse donne un bref aperçu des connaissances actuelles sur les herbiers vietnamiens et des possibles travaux scientifiques à mener. / The overall objective was to assess macrobenthos response to marine Zostera noltii seagrass dynamics (colonization, maturation, destruction, restoration), in Arcachon Bay, a French Southwestern lagoon.When seagrass starts to develop, the structure of macrofauna community immediately diverges between sand and seagrass habitats, without however modifying tested biotic indices (BENTIX, BOPA, AMBI). As well, population of the dominant bivalve, the cockle (Cerastoderma edule), suffers from seagrass development. Their parasite (trematode) community are impacted, but not sufficiently to explain cockle deficit in seagrass.At the scale of the Bay, seagrass development (considered as a sign of “good health”) is compared to the fitness of the two dominant infaunal bivalves, the Manila clam (Ruditapes philippinarum) and the cockle (Cerastoderma edule), measured in terms of disease prevalence. There was no correlation among seagrass cover rate and the prevalence of three diseases: trematodiosis, perkinsosis and Brown Muscle Disease.Between 2002 and 2010, seagrass cover decreased by 1/3. When looking at community structure and dominant species, there were moderate differences within (among 12 stations) and among years, independently of seagrass decline. Among biotic indicators, multivariate index MISS was in adequation with the relative similarity of macrofauna structure among groups discriminated by MISS analysis.In 2005, dredging activities in Arcachon Bay led in burying 0.32 km2 of Z. noltii. Macrobenthos structure was immediately modified and did not recover in places buried by sand. Conversely, macrobenthos (infauna) recovered rapidly in areas cover by mud, while seagrass began to develop again five years after work. The last chapter of the thesis provides a brief insight of the seagrass in Vietnam, the actual knowledge and what could be investigated.

A utilização da comunidade bentônica em biomonitoramento, como indicadora da qualidade de ambientes aquáticos, encontra-se atualmente bem estabelecida. Das duas abordagens sugeridas pelo Protocolo de Avaliação Rápida da USEPA, a que utiliza um único meso-hábitat mostra-se ideal para o biomonitoramento sendo, portanto, necessário estabelecer qual meso-hábitat utilizar. Este trabalho pretende avaliar a sensibilidade e adequabilidade de diferentes meso-hábitat ribeirinhos em biomonitoramento. Foram estabelecidos oito pontos de amostragem, localizados nos rios Atibainha, Cachoeira e Atibaia, na Bacia Hidrográfica do Rio Piracicaba, São Paulo. Amostras foram coletadas na estação chuvosa (março), para análise de variáveis ambientais (água e sedimento) e biótica (macroinvertebrados bentônicos). Os organismos da comunidade bentônica foram identificados ao nível de família para os principais taxa. Os dados ambientais e bióticos foram submetidos à análise de agrupamento e ordenação, e para o diagnóstico da qualidade do ambiente aquático, índices individualizados e abordagem multimétrica foram utilizados. Tanto as variáveis ambientais quanto a biótica separaram nitidamente regiões de alto (3ª e 4ª ordens) e baixo gradiente (5ª e 6ª ordens). Dos meso-hábitats analisados por meio da comunidade bentônica, apenas canal e margem deposicional mostraram-se promissores e destes, margem deposicional mostrou-se o mais adequado para biomonitoramento, tanto por discernir o gradiente de poluição existente quanto por possibilitar a avaliação integrada de variáveis bióticas, químicas e toxicológicas, o que minimizaria esforços com acréscimo de informações. / The use of benthic communities in biomonitoring, as indicator of aquatic environmental quality is currently well established. Considering the two approaches suggested by Rapid Assessment Protocol of US-EPA, the single mesohabitat approach is ideal for the practical purposes of biomonitoring, being hence necessary to establish which meso-habitat to use. This paper aims to evaluate the sensitivity and suitability of different river meso-habitats for biomonitoring. Eight sampling sites were established along Atibainha, Cachoeira and Atibaia Rivers, in Piracicaba River basin, São Paulo State, Brazil. Sampling were carried out in rainy season (March) to evaluate environmental (water and sediment) and biotic (benthic macroinvertebrates) parameters. The major benthic taxa were identified to family level.. Environmental and biotic data were submitted to cluster and ordination analysis, and for the quality of aquatic environment diagnosis, individualized index and multimetrics approach were used. Both environmental and biotic parameters distinctly discriminated upper (3rd and 4th orders) from lower (5th and 6th orders) gradient regions. Among the meso-habitats analyzed by mean of the benthic community, only channel and depositional bank were promising and of the two, deposicional bank proved to be the most adequate for biomonitoring, both for discerning pollution gradient and for enabling an integrated assessment of biotic, chemical and toxicological parameters, minimizing efforts and adding information

Os objetivos deste estudo foram desenvolver o protocolo do Método do Índice de Qualidade (MIQ) para avaliação da qualidade sensorial da pescada amarela parcialmente eviscerada e armazenada em gelo; avaliar as alterações sensoriais, químicas e microbiológicas da pescada amarela durante o armazenamento e indicar os parâmetros mais adequados para avaliação da qualidade propondo limites de aceitação para a espécie. Quatro lotes com peixes recém capturados em Praia Grande-SP foram transportados à Faculdade de Zootecnia e Engenharia de Alimentos (FZEA) e armazenados entre camadas de gelo (0-1ºC) em câmara fria. Periodicamente 5 peixes foram amostrados e submetidos às análises sensorial (para desenvolvimento do protocolo MIQ e posterior avaliação), microbiológicas (contagens de psicrotróficos, coliformes totais e fecais, Salmonella sp, estafilococos coagulase positiva) e químicas (bases nitrogenadas voláteis-BNV, trimetilamina-TMA, triptofano livre e uréia). A qualidade da pescada amarela comercializada em 14 pontos de venda nas cidades de Santos, São Vicente e Praia Grande foi avaliada utilizando-se o protocolo MIQ desenvolvido, análises microbiológicas e químicas. O protocolo MIQ desenvolvido apresentou aumento linear do índice de qualidade (IQ) ao longo do armazenamento. Nos peixes do lote 1, contagens de psicrotróficos atingiram 107ufc/g no 14º dia. Nos lotes 3 e 4 esse limite foi alcançado entre o 6º e 8º dia. Contagens de E.coli superiores a 102ufc/g foram observadas em 9,5% dos peixes do lote 1 após 21 dias de armazenamento e em 15,25% dos peixes do lote 3 no 6º e 9º dia. Staphylococcus aureus estava ausente em todos os peixes e Salmonella sp foi detectada foi detectada em 7,4% das pescadas amarelas analisadas. Os valores finais de BNV variaram de 23.8 mg/100g a 159 mg/100g em pescadas amarelas e foi dependente da carga microbiana inicial. Todos os lotes apresentaram aumento no teor de TMA, que variou entre 0,18 mg/100g e 15,44mg/100g. As amostras de pescada amarela comercializadas apresentaram IQ variando de 2 a 23, indicando um tempo provável pós captura de 3 até 14 dias. Todos os peixes analisados estavam livres de Salmonella sp e E.coli. Staphylococcus aureus foi determinado em níveis abaixo do limite estipulado pela legislação. Contagens de psicrotróficos acima de 107ufc/g foram observadas em 50% dos peixes. Coliformes totais variaram de 102ufc/g até 107ufc/g. Os valores de TMA e BNV foram maiores que os estabelecidos pela legislação brasileira em 50% e 65% dos peixes, respectivamente. No entanto, em relação à TMA, concentrações superiores a 4mg/100g foram encontradas em peixes que apresentaram contagens de psicrotróficos, concentração de BNV e IQ aceitáveis, sugerindo valores em torno de 12-14mg TMA/100g de peixe como limite adequado para consumo de pescada amarela O valor 30mg de BNV/100g recomendado pela legislação brasileira parece ser adequado como limite de comercialização de pescada amarela, porém a concentração de BNV não está diretamente relacionada ao tempo de armazenamento desde a captura. Triptofano livre e uréia não foram parâmetros químicos adequados para avaliação do frescor da pescada amarela. O protocolo MIQ foi eficiente para a avaliação da qualidade de pescada amarela, apresentando boa correlação entre a perda da qualidade sensorial e o tempo de estocagem. A análise de correlação entre os resultados das diversas análises sugere que a pescada amarela, quando eviscerada e resfriada em gelo, mantém características adequadas para consumo até o 8º dia de armazenamento. Diversos estabelecimentos comerciais de Santos, São Vicente e Praia Grande disponibilizam para os consumidores pescada amarela resfriada em condições inadequadas para consumo de acordo com a legislação brasileira. / The objectives of this study were to develop a Quality Index Method (QIM) scheme for sensory evaluation of partially gutted Acoupa weakfish; to evaluate the sensory, chemical and microbial changes during storage in ice and to suggest the best parameters for quality evaluation and limits of acceptability of this fish species. Four groups of Acoupa weakfish caught in Praia Grande, São Paulo state, were transported to the Faculdade de Zootecnia e Engenharia de Alimentos (FZEA) within 24h of their capture and stored between layers of ice (0-1ºC) in chilling room. Periodically, 5 fishes were sampled and evaluated by sensory (QIM), microbial (counts of psychrotrophic, total and faecal coliforms, Salmonella sp and coagulase-positive Staphylococcus) and chemical (volatile base nitrogen-VBN, trimethylamine-TMA, free tryptophan and urea) analysis. The quality of samples of Acoupa weakfish commercialized in fourteen markets in Santos, São Vicente and Praia Grande cities was also evaluated. The QIM scheme presented linear increase of QI during the storage. In fishes of group 1 the counts of psychrotrophic bacteria reached 107cfu/g at the 14th day of storage. In groups 3 and 4 this limit was reached between days 6 and 8. Counts of E. coli higher than 102cfu/g were detected in 9.5% of the fishes belonging to the group 1 after day 21. This level was also detected in 15.25% of the fishes of the group 3 after days 6 and 9. Staphylococcus aureus was not detected and Salmonella sp was present in 7.4% of the Acoupa weakfish in groups 1 and 2. VBN contents ranged from 23.8 mg/100g to 159 mg/100g and was affected by the microbial load at the beginning of the storage. All the groups of Acoupa weakfish in this study, presented increases in TMA contents during storage and the values ranged between 0.18 and 15.44mg/100g. The samples of Acoupa weakfish obtained from markets showed QI ranging from 2 to 23, suggesting a storage time between 3 to 14 days respectively. All the fishes were free from Salmonella sp and E. coli. Counts of Staphylococcus aureus were lower than the amount determined by the Brazilian legislation. Counts of psychrotrophic bacteria higher than 107cfu/g were observed in 50% of the fishes. Counts of total coliforms ranged from 102cfu/g till 107cfu/g. TMA and VBN contents were higher than the amount allowed by the Brazilian legislation in 50% and 65% of the fishes, respectively. Nevertheless, TMA contents higher than 4mg/100g, were detected in fishes presenting low counts of psychrotrophics, low VBN levels and low QI. Contents ranging from 12-14mg TMA/100g of fish are the suggested limits of consumption for Acoupa weakfish. The limit of 30mg of VBN/100g of fish, allowed by the Brazilian legislation is the appropriate amount for commercialization of Acoupa weakfish, although the VBN contents are not directly related to the storage time. Free tryptophan and urea were not useful as quality indices for Acoupa weakfish. The QIM scheme was effective for quality evaluation of Acoupa weakfish showing significant correlation with quality loss and storage time. Results of correlation analysis allow suggesting that Acoupa weakfish, when gutted and maintained in ice, is suitable for consuming until day 8. Several markets in Santos, São Vicente and Praia Grande commercialize chilled Acoupa weakfish that are unacceptable for consumption according to the Brazilian legislation.