Orientador: Luiz Carlos Forti / Banca: Wilson Baliali Crocomo / Banca: Maria Aparecida C. Boaretto / Banca: Ivone Paschoal Garcia / Banca: Alberto Cavalcanti Vitório / Resumo: As formigas cortadeiras, insetos pertencentes aos gêneros Atta e Acromyrmex (Hymenoptera: Formicidae), recebem, no Brasil, os nomes populares de saúvas e quenquéns. Devido a seu hábito alimentar polífago ocupam diversos ambientes, acarretando danos econômicos em áreas cultivadas. As partes vegetais cortadas são transportadas para suas colônias e preparadas para servir de substrato ao fungo simbionte do qual se alimentam. Atualmente, o método mais empregado para o seu controle é a aplicação de iscas tóxicas, e, para muitas espécies, proporciona excelentes resultados. Porém, para uma espécie em particular, os métodos existentes são considerados insatisfatórios. Trata-se de Atta capiguara, conhecida como saúva parda, que causa expressivos prejuízos à pecuária. A ineficiência das iscas tóxicas destinadas ao controle dessa espécie deve-se ao fato de que as mesmas são fabricadas contendo apenas polpa cítrica; como A. capiguara seleciona essencialmente monocotiledôneas, as iscas não são atrativas e, conseqüentemente, não transportadas pelas operárias. Dessa maneira, o presente trabalho objetivou desenvolver iscas destinadas ao controle da saúva parda, partindo da hipótese que a adição de espécies monocotiledôneas à matriz das iscas causa efeito atrativo sobre as operárias, tornando os pelletes mais transportados. Assim, foram utilizadas espécies vegetais naturalmente selecionadas durante o forrageamento por essas formigas, no caso a cana-de-açúcar, o capim jaraguá e o capim elefante. A adição dessas gramíneas às iscas foi feita por meio de incorporação, impregnação e pulverização de extratos, além da adição direta de matéria seca vegetal em substituição parcial à polpa cítrica, sendo todo o material previamente preparado em laboratório...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The leaf-cutting ants, insects belonging to the genus Atta and Acromyrmex (Hymenoptera: Formicidae), they have, in Brazil, the popular names of saúvas and quenquéns. Due to its polyfagic habit, they live in the most several environments, bringing out economic damages in cultivated areas. The pieces of the vegetables that they cut, are transported for its colonies and prepared to serve of substratum to the symbiont mushroom which they feed. Now, the method more employed for its control is the application of toxicant baits, and, for a lot of species, it provides excellent results. Even so, for a species in particular, the existent methods are considered unsatisfactory. It is Atta capiguara, known as "saúva parda", that causes expressive damages to the pastures. The inefficiency of the toxicant baits destined to the control of that species is due to the fact that the same ones are manufactured just contends citric pulp; as A. capiguara selects monocotyledonous essentially, the baits are not attractive and, consequently, not transported by the workers. In that way, the present work objectified to develop baits destined to the control of the "saúva parda", based on hypothesis that the addition of monocotyledonous species to the base of the baits should cause an attractive effect on the workers, turning the pellets more transported by the same ones. Thus, were used vegetable species that they are naturally selected during the foraging by the ants, in this case sugar-cane, jaraguá grass and elephant grass. The addition of those grasses to the baits was made by incorporation, impregnation and pulverization of the extracts, besides the direct addition of dry vegetable matter in partial substitution to the citric pulp, being previously the whole material prepared in laboratory...(Complete abstract click electronic access below) / Doutor

Buildings are one of the major consumers of energy and make up a considerable portion in the generation of greenhouse gases. Green roofs are regarded as an appropriate strategy to reduce the heating and cooling loads in buildings. However, their energy performance is influenced by different design parameters which should be optimized based on the corresponding climate zone. Previous investigations mainly analyzed various design parameters in a single climate zone. However, the interaction of parameters in different climate zones was not considered. Also, the studies have been conducted mostly for commercial or residential buildings. Among different building types, schools with large roof surface are one of the major consumers of energy in North America. However, the literature review shows the lack of study on the effect of green roof on the thermal and energy performance of this type of building. This study performs a comprehensive parametric analysis to evaluate the influence of the green roof design parameters on the thermal or energy performance of a secondary school building in four climate zones in North America (i.e. Toronto, ON; Vancouver, BC; Las Vegas, NV and Miami, FL). Soil moisture content, soil thermal properties, leaf area index, plant height, leaf albedo, thermal insulation thickness and soil thickness were used as variables. Optimal parameters of green roofs were found to be closely related to meteorological conditions in each city. In terms of energy savings, the results show that the light substrate has better thermal performance for the uninsulated green roof. Also, the recommended soil thickness and leaf area index in the four cities are 0.15 m and 5, respectively. The optimal plant height for the cooling dominated climates is 0.3 m and for the heating dominated cities are 0.1 m. The plant albedo had the least impact on the energy consumption while it is effective in mitigation effect of heat island effect. Finally, unlike the cooling load which is largely influenced by the substrate and vegetation, the heating load is considerably affected by the thermal insulation instead of green roof design parameters. / Graduate

Thesis (MSc (Biochemistry))--University of Limpopo (Medunsa Campus), 2010. / Background: Clausena anisata (C. anisata) (Willd) Hook [Family: Rutaceae] is one of the South African indigenous medicinal plant whose blood glucose lowering effect has been demonstrated in animal models of diabetes mellitus. However, the mechanism(s) by which extracts of these plants exert their blood glucose lowering effect have not been investigated Objectives of the study: The objectives of the current study were to investigate in vitro inhibitory effects of different C. anisata leaf extracts on the activities of human urinary α-amylase, Bacillus stearothermophilus α-glucosidase and rat hepatic glucose 6-phosphatase and to characterize the enzyme inhibitory effect of the extracts on these enzymes with respect to the mode of inhibition (type of inhibition) and IC50 values (measure of inhibition potency). Another objective of the study was to confirm the enzyme inhibitory effects of C. anisata in vivo by measuring postprandial glucose levels in alloxan induced diabetic rats after oral administration of sucrose. Results: Aqueous and methanolic extracts of C. anisata leaves inhibited human urinary α-amylase with IC50 values of 1947 ± 50 and 2436 ± 62 µg/ml respectively. Inhibitions of α-amylase by these extracts were however, significantly less than that of the reference drug acarbose (84 ± 11 µg/ml) (P < 0.001). The mode of inhibition of these extracts on human urinary α-amylase appears to be a reversible non-competitive one. Acetone and hexane extracts of C. anisata inhibited Bacillus stearothermophilus α-glucosidase with IC50 values of 1020 ± 32 and 2068 ± 59 µg/ml respectively. Inhibition of Bacillus stearothermophilus α-glucosidase by these two extracts was also significantly less than that produced by acarbose (36 ± 11 µg/ml) (P < 0.001). The mode of inhibition of Bacillus stearothermophilus α-glucosidase by the acetone extract was found to be reversible competitive in this case. Aqueous and methanolic extracts of C. anisata leaves also inhibited hepatic glucose 6-phosphatase with IC50 values of 493.6 ± 12 and 1012 ± 58 µg/ml respectively. In this case the effect of the aqueous extract was significantly less than that of the reference inhibitor of glucose 6-phosphatase, sodium vanadate (1651 ± 46 µg/ml) (P < 0.05). The mode of inhibition of glucose 6-phosphatase by C. anisata aqueous leaf extract was found to be irreversible. Furthermore, oral administration of C. anisata acetone leaf extract to normal and alloxan induced diabetic rats, 30 minutes before sucrose loading failed to prevent the rise in postprandial glucose levels in these animals. Conclusions: Although both C. anisata aqueous and hexane leaf extract inhibited human urinary α-amylase and Bacillus stearothermophilus α-glucosidase in vitro, this does not appear to be the case in vivo. C. anisata aqueous leaf extract appeared to be a more potent inhibitor of rat hepatic glucose 6-phosphatase than the known inhibitor of the catalytic subunit of this multi-component enzyme system.

A study was conducted to evaluate the use of Leucaena leucocephala leaf meal (LLM) as a protein supplement for pigs. In addition, an evaluation of detoxifying LLM, by sun-drying, water-soaking, or treating with ferrous sulphate (FeS04) solution was undertaken. The research involved two experiments; a growth study and a metabolic study. In the growth study sixteen, 12 weeks old Large White x Landrace pigs (average body weight 22.9 ± 2.12 kg) were fed four experimental rations; a commercial grain-based grower /finisher ration (control); or a ration containing 20% of either sun-dried LLM, water-soaked LLM, or FeS04-treated LLM, replacing the basal diet. There was a significant (P<0.05) decrease in liveweight gain, feed intake and feed conversion efficiency in pigs fed the ration containing sun-dried LLM. Growth rate, feed intake and feed conversion efficiency were not affected by the addition of water-soaked and FeS04-treated LLM to the basal diet. Triiodothyronine (T3) and thyroxine (T4) levels in the blood plasma were not affected by the dietary treatments. However, addition of FeS04-treated LLM to the basal diet significantly (P<0.05) decreased the back fat thickness of the pigs. In the metabolic study, the digestible dry matter (DDM) and digestible CP (DCP) were measured as well as mimosine, 3-hydroxy-4-(1H) pyridone (3,4-DHP) and 2,3DHP output in the faeces and urine. / Addition of water-soaked LLM to the diet significantly (P<0.05) lowered the DDM of the diet, whereas addition of FeS04-treated LLM significantly (P<0.05) reduced the DCP. Sun-drying, water-soaking and treatment of LLM with FeS04 solution, did not enhance the output of mimosine or 3,4-DHP in the urine and faeces. The results suggest that water soaking or treatment with FeS04 solution reduces the antinutritional factors (presumably including mimosine) and therefore improves the nutritional quality of LLM containing diets for pigs.

Graduation date: 1991

Graduation date: 1990

If a partially hyperbolic diffeomorphism on a torus of dimension d greater than 3 has stable and unstable foliations which are quasi-isometric on the universal cover, and its center direction is one-dimensional, then the diffeomorphism is leaf conjugate to a linear toral automorphism. In other words, the hyperbolic structure of the diffeomorphism is exactly that of a linear, and thus simple to understand, example. In particular, every partially hyperbolic diffeomorphism on the 3-torus is leaf conjugate to a linear toral automorphism.

If a partially hyperbolic diffeomorphism on a torus of dimension d greater than 3 has stable and unstable foliations which are quasi-isometric on the universal cover, and its center direction is one-dimensional, then the diffeomorphism is leaf conjugate to a linear toral automorphism. In other words, the hyperbolic structure of the diffeomorphism is exactly that of a linear, and thus simple to understand, example. In particular, every partially hyperbolic diffeomorphism on the 3-torus is leaf conjugate to a linear toral automorphism.

Taxonomic diversity, biology and ecology of leaf endophytes were studied from some evergreen plants including Arbutus unedo, Buxus sempervirens, flex aquifolium, Laurus nobilis, Ligustrum vulgare, Prunus lusitanica, Rhododendron ponticum, Rhododendron sp., and Skimmia sp. from England, and some others from China. It was found: 1. A great number of fungal species, including several new species and new British records, have been isolated. Distribution patterns of endophyte assemblages and their variations between plant species and geographical locations are described. 2. Comparisons of leaf endophytes and saprobes of R. ponlicum at the same locality showed they belonged to two different ecological groups. This was further confirmed by study on endophytes and saprobes from a number of plant species growing in the same locality. 3. Host specificity of endophytic fungi at the species level was rare and this was supported by comparisons of endophyte assemblages from both taxonomically related (same family) and unrelated (different families) plant species. Molecular characterisations of Phyllosticta species confirmed this. 4. Infection and colonisation studies during a two year period showed that leaf endophytes of R. ponlicum were horizontally transmitted. Internal bud material was sterile and became infected by aerial spores. The infection and colonisation level of endophytes were strongly affected by environmental conditions. 5. Phylogenetic studies of Phyllosticta based on ITS 1-5.8s rDNA-ITS2 sequences concluded there was no evidence to show that the evolution of host plants of Phyllosticta species and ITS were related. Most Phyllosticta species from the same locality were found to have a broad host range and occurred on many taxonomically unrelated plants in the same locality. P. concentrica was separated into 4 species including P. concentrica on Hedera, P. arxii on Ilex, P. maxima on Rhododendron and P. taxi on Taxus.

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