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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Composição mineral do leite humano em diferentes estágios de lactação.

Lima, Joseni França Oliveira January 2009 (has links)
p. 1-102 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-04-09T17:44:48Z No. of bitstreams: 1 Dissertacao Joseni Lima SEG.pdf: 487372 bytes, checksum: 59ca931b8411aed4bf2a20d09cef54c5 (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-04-10T14:03:51Z (GMT) No. of bitstreams: 1 Dissertacao Joseni Lima SEG.pdf: 487372 bytes, checksum: 59ca931b8411aed4bf2a20d09cef54c5 (MD5) / Made available in DSpace on 2013-04-10T14:03:51Z (GMT). No. of bitstreams: 1 Dissertacao Joseni Lima SEG.pdf: 487372 bytes, checksum: 59ca931b8411aed4bf2a20d09cef54c5 (MD5) Previous issue date: 2009 / O leite humano é um alimento completo, capaz de suprir todas as necessidades fisiológicas e nutricionais da criança. Vários estudos destacam a importância do aleitamento materno para a saúde e nutrição do lactente, em especial pela sua proteção contra doenças e pelo valor nutricional, contudo poucas investigações abordam seu conteúdo mineral. O objetivo deste estudo foi quantificar os elementos minerais cálcio, magnésio, potássio, ferro e zinco em 102 amostras de leite humano coletadas de doadoras de cidades do Vale do Jiquiriçá, Bahia em diferentes estágios: 1, 6 e 12 meses de lactação bem como estudar a relação entre os minerais e as variáveis maternas. Para o tratamento das amostras foi utilizado um procedimento de decomposição por via úmida com uma mistura composta de HNO3, H2SO4 e H2O2. A determinação dos minerais foi realizada empregando um espectrômetro de emissão optica com plasma de argônio indutivamente acoplado (ICP OES). Os valores médios obtidos para os elementos estudados no 1º. mês de lactação foram: Ca (204,11 ± 49,15 mg L-1); Mg (25,17 ± 6,58 mg L-1); K (497,26 ± 103,09 mg L-1); Fe (0,48 ± 0,27 mg L-1); Zn (2,56 ±0,90 mg L-1). Para os 6 meses, com exceção do Mg (26,99 ±9,64 mg L-1) observou-se um ligeiro declínio nas concentrações médias do Ca (177,70 ±48,60 mg L-1); K (403,61 ±106,31 mg L-1); Fe (0,26 ± 0,16 mg L-1); Zn (1,14 ± 0,63 mg L-1). Para os 12 meses de lactação as médias declinaram mais ainda, identificando as seguintes concentrações Ca (169,54 ± 43,18 mg L-1); K (362,53 ± 88,64 mg L-1); Fe (0,38 ± 0,25 mg L-1); Zn (0,92 ± 0,66 mg L-1), exceto para Mg (25,17 ± 6,43 mg L-1). Quando analisadas por pareamento (teste t) o declínio foi significante para o Ca (ρ=0,029); K (ρ=0,001); Fe (ρ=0,006) e Zn (ρ<0,001) no intervalo de 1/6 meses. Contudo, no intervalo de 6/12 meses, apenas o teor de Ca manteve diferença estatisticamente significante no declínio ao longo de tempo (ρ=0,01). As concentrações obtidas para Mg não apresentam variação média significante ao longo da lactação. Os resultados apresentados demonstram que a composição mineral do leite humano modifica-se à medida que o aleitamento materno se prolonga e que o Fe é o mineral que apresenta maior variabilidade. Observou-se, através da comparação de médias, influência significante do tipo de parto para os resultados obtidos para Mg no 6º mês de lactação (ρ= 0,028) e do estado nutricional materno para Ca no 12º mês de lactação (ρ= 0,04) a 5% de probabilidade. / Salvador
22

Manejo Pós-Colheita de Peras Rocha / Postharvest handling of Rocha pears

Martin, Mariuccia Schlichting de 26 July 2013 (has links)
Made available in DSpace on 2016-12-08T16:44:45Z (GMT). No. of bitstreams: 1 PGPV13MA119.pdf: 581896 bytes, checksum: de7253adf5d31585d5877cf8a34747d5 (MD5) Previous issue date: 2013-07-26 / The aim of this study was to evaluate the effect of different techniques for inducing maturation and controlled atmosphere storage on the quality of Rocha pears, as well as evaluating the relationship of Ca, Mg, K, and its relations with the susceptibility of fruits to internal browning. Three independent experiments were performed. The first experiment aimed to evaluate the effect of different periods of chilling and application of ethylene on quality and ripening of Rocha pears. In the 2011/2012 season four periods of chilling at 3°C were evaluated, namely zero (control), 14, 28 and 42 days, and the effect of 100 ppm of C2H4 by one and two days. In the 2012/2013 season five periods of chilling at 3°C were evaluated as follows: zero, 15, 30, 45 and 60 days. The second experiment aimed to evaluate the effect of different conditions of controlled atmosphere (CA) and inducing of mass loss (IML) on the quality of Rocha pears. The fruits were from São Joaquim, SC, and were stored for eight months and fifteen days at -0.5 ± 0.1 ° C and 96±1% RH. The storage conditions evaluated were: 21.0 kPa O2 + <0.03 kPa CO2 (RA), 1.0 kPa O2 + <0.03 kPa CO2, 2.0 kPa O2 + 1.0 kPa CO2, 1.0 kPa O2 + 1.0 kPa CO2, 1.0 kPa O2 + 2.0 kPa CO2, and 1.0 kPa O2 + 2.0 kPa CO2 + IML 2.6%. The third experiment aimed to evaluate the relationship of the mineral content of the flesh. The third experiment aimed to evaluate the relationship of Ca, Mg, K and relationships K/Ca and (K+Mg)/Ca in the pulp with the incidence and severity of internal browning in Rocha pears submitted at high CO2 partial pressures (20 kPa) and low O2 partial pressures (<0.4 kPa). The increase in the chilling period provided a higher yellowing of the fruit skin and increased rates of respiration and ethylene production. In experiment 1, all treatments for induction of ripening showed lower flesh firmness and force required to penetrate the flesh compared to control, developing buttery texture after seven days at ambient conditions. Chilling for 15 days at 3ºC and the application of 100 ppm of C2H4 for two days were the most appropriate conditions to induce ripening in the Rocha pears. In experiment 2, storage in RA provide fruits with yellower skin, lower soluble solids content, lower titratable acidity and lower acceptance in sensory tests. The fruits stored in RA and CA with <0.03 kPa partial pressure showed higher flesh firmness and force required to penetrate the flesh after seven days of shelf life, not developing buttery texture suitable for consumption. The CA conditions of 1.0 kPa O2 + 1.0 kPa CO2 and 1.0 kPa O2 + 2.0 kPa CO2 provided better quality of Rocha pears, allowing a normal ripening fruit after extended storage. The Ca, Mg and K contents and K/Ca and (K+Mg)/Ca relationships had no clear relation with the susceptibility of Rocha pears to internal browning / O objetivo deste trabalho foi avaliar o efeito de diferentes técnicas para indução do amadurecimento e do armazenamento em atmosfera controlada sobre a qualidade de peras Rocha , bem como avaliar a relação dos nutrientes Ca, Mg, K e suas relações com a suscetibilidade dos frutos ao escurecimento de polpa. Foram realizados três experimentos independentes. O primeiro experimento teve como objetivo avaliar o efeito de diferentes períodos de choque de frio e da aplicação de etileno sobre a qualidade e o amadurecimento de peras Rocha . Na safra 2010/2011, foram avaliados quatro períodos de choque de frio a 3ºC, sendo eles zero (controle), 14, 28 e 42 dias, e o efeito da aplicação de 100 ppm de C2H4 por um e por dois dias. Na safra 2012/2013 foram testados cinco períodos de choque de frio a 3ºC, sendo eles: zero, 15, 30, 45 e 60 dias. O segundo experimento teve como objetivo avaliar o efeito de diferentes condições de atmosfera controlada (AC) e da indução de perda de massa (IPM) sobre a qualidade de peras Rocha . Frutos provenientes do município de São Joaquim, SC, foram armazenados por oito meses e quinze dias a -0,5±0,1ºC e UR de 96±1%. As condições de armazenamento avaliadas foram: 21,0 kPa de O2 + <0,03 kPa de CO2 (AR); 1 kPa de O2 + <0,03 kPa de CO2; 2,0 kPa de O2 + 1,0 kPa de CO2; 1,0 kPa de O2 + 1,0 kPa de CO2; 1,0 kPa de O2 + 2,0 kPa de CO2; e 1 kPa de O2 + 2,0 kPa de CO2 + IPM de 2,6%. O terceiro experimento objetivou avaliar a relação dos teores de Ca, Mg, K e as relações K/Ca e (K+Mg)/Ca na polpa com a incidência e severidade de escurecimento de polpa em peras Rocha submetidas a altas pressões parciais de CO2 (20 kPa) e baixas pressões parciais de O2 (<0,4 kPa). O aumento do período de choque de frio proporcionou aos frutos maior amarelecimento da casca e aumento das taxas respiratória e de produção de etileno. No experimento 1, todos os tratamentos para indução do amadurecimento apresentaram menor firmeza de polpa e de força para penetração da polpa em relação ao controle, desenvolvendo textura amanteigada após sete dias em condições ambiente. O choque de frio por 15 dias a 3ºC e a aplicação de 100 ppm de C2H4 por dois dias foram as condições mais indicadas para induzir o amadurecimento de peras Rocha . No experimento 2, o armazenamento refrigerado propiciou frutos com casca mais amarela, menor teor de sólidos solúveis, menor acidez titulável e baixa aceitação nos testes sensoriais. Os frutos mantidos em AR e em AC com pressão parcial de CO2 de <0,03 kPa apresentaram maior firmeza de polpa e de força para penetração da polpa após sete dias de exposição dos frutos à temperatura ambiente, não desenvolvendo textura amanteigada própria para o consumo. As condições de AC de 1,0 kPa de O2 + 1,0 kPa de CO2 e 1 kPa de O2 + 2,0 kPa de CO2 proporcionaram melhor manutenção da qualidade de peras Rocha , permitindo o amadurecimento normal dos frutos após o armazenamento prolongado. Os teores de Ca, Mg, K e as relações K/Ca e (K+Mg)/Ca não apresentaram clara relação com o escurecimento de polpa em peras Rocha
23

Studium fyzikálně-mechanických vlastností krystalinických hornin ve vztahu k plánovanému hlubinnému úložišti radioaktivních odpadů / Physico-mechanical properties of crystalline rocks associated with planned deep geological repository for a radioactive waste

Havlíčková, Dagmar Unknown Date (has links)
The Czech deep repository development programme resulted in identification of several localities with favourable geological conditions. The Czech concept of a deep repository construction targets on crystalline host rocks. The dissertation focuses on combined petrographic and physico-mechanical properties (rebound hardness, uniaxial and triaxial compressive strength, indirect tensile strength) of crystalline rocks (durbachite, ganulite) from the most favoured localities – Horka near Velké Meziříčí and Kraví hora near Dolní Rožínka.
24

Avaliação da atividade antioxidante e antimicrobiana de extratos de araçá (Psidium grandifolium Mart. ex DC.) obtidos por líquido pressurizado (PLE) e por fluido supercrítico (SFE) / Evaluation of the antioxidante and atimicrobial activity of araçá extracts (Psidium grandifolium Mart. ex DC.) obtained by pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE)

Bittencourt, Gabriela Marques 26 July 2018 (has links)
O araçá é um fruto, pertencente à espécie Psidium grandifolium Mart. ex DC, nativo da mata atlântica brasileira pouco caracterizado pela literatura ciêntífica. Esta pesquisa visou estudar o rendimento de extração e avaliar as atividades antioxidante e antimicrobiana do óleo essencial de araçá obtido por extração com dióxido de carbono supercrítico (SFE) e dos diferentes extratos obtidos por extração com etanol pressurizado (PLE) seguindo um delineamento composto central rotacional com temperatura e tempo estático como variáveis independentes estudadas. Avaliou-se também o perfil de voláteis do óleo essencial, o teor de compostos fenólicos totais dos extratos etanólicos e as alterações causadas na matriz vegetal por diferentes processos de extração. Com a SFE conseguiu-se extrair toda a fração lipídica do fruto (2,33% &plusmn; 0,04.10-2%), a análise dos compostos voláteis do óleo essencial obtido permitiu inferir que este possui diversos compostos com potencial bioativo tais como E-cariofileno (17.56%), &alpha;-humuleno (16,26%) e &beta;-sesquifelandreno (14.27%); porém este óleo essencial não apresentou atividade antioxidante relevante. O extrato etanólico com maior rendimento (17, 49%) foi obtido a 74 °C por 6 min, mesma condição em que obteve-se a maior atividade antioxidante (EC50 = 6,37 mg/mL), porém o maior teor de compostos fenólicos totais (136,95 mg EGA/100 g de massa seca) foi obtido quando aplicou-se 60°C por 9 min. Em relação à atividade antimicrobiana, tanto os extratos obtidos por PLE quanto por SFE apresentaram atividade contra cepas de P. aeruginosa, S. aureus e B. cereus, somente extratos etanólicos apresentaram atividade contra cepas de L. monocytogenes e nenhum dos extratos apresentaram atividade contra cepas de B. subtilis, E. coli e Salmonella. Em ambos os extratos foi possível identificar compostos com potencial aplicação farmacológica. O estudo de processos de extração que envolvam inovação tecnológica na obtenção extratos com atividade biológica visa contribuir com o extrativismo consciente ou estimular o plantio em maior escala de mais um fruto tropical empregado na medicina popular brasileira. / The araçá is a fruit, belonging to the species Psidium grandifolium Mart. ex DC, native of the Brazilian Atlantic Forest, is not largely characterized by the scientific literature. This research work aimed to study the extraction yield and to evaluate the antioxidant and antimicrobial activities of the araçá essential oil obtained by supercritical carbon dioxide extraction (SFE) and the different extracts obtained by pressurized ethanol extraction (PLE) following a central composite design with temperature and static time as independent variables studied. It was also evaluated the volatile profile of the essential oil, the content of total phenolic compounds of the ethanolic extracts and the changes caused in the vegetal matrix by different extraction processes. SFE was able to extract the whole lipid fraction of the fruit (2.33% &plusmn; 0.04.10-2%), the analysis of the volatile compounds of the essential oil obtained allowed to infer that it has several compounds with bioactive potential such as E-caryophyllene (17.56%), &alpha;-humulene (16.26%) and &beta;-sesquipelandene (14.27%); but this essential oil had no relevant antioxidant activity. The highest ethanolic extract (17, 49%) was obtained at 74 °C for 6 min, the same condition in which the highest antioxidant activity was obtained (EC50 = 6.37 mg/mL), but the higher content of total phenolics contente (136.95 mg EGA / 100 g dry mass) was obtained when 60 °C was applied for 9 min. In relation to the antimicrobial activity, both extracts obtained by PLE and SFE showed activity against P. aeruginosa, S. aureus and B. cereus strains, only ethanolic extracts showed activity against L. monocytogenes strains and none of the extracts presented activity against B. subtilis, E. coli and Salmonella strains. In both extracts it was possible to identify compounds with potential pharmacological application. The study of extraction processes that involve technological innovation in obtaining extracts with biological activity aims to contribute to the conscious extraction or stimulate the larger scale cultivation of another tropical fruit used in Brazilian popular medicine.
25

Avaliação da atividade antioxidante e antimicrobiana de extratos de araçá (Psidium grandifolium Mart. ex DC.) obtidos por líquido pressurizado (PLE) e por fluido supercrítico (SFE) / Evaluation of the antioxidante and atimicrobial activity of araçá extracts (Psidium grandifolium Mart. ex DC.) obtained by pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE)

Gabriela Marques Bittencourt 26 July 2018 (has links)
O araçá é um fruto, pertencente à espécie Psidium grandifolium Mart. ex DC, nativo da mata atlântica brasileira pouco caracterizado pela literatura ciêntífica. Esta pesquisa visou estudar o rendimento de extração e avaliar as atividades antioxidante e antimicrobiana do óleo essencial de araçá obtido por extração com dióxido de carbono supercrítico (SFE) e dos diferentes extratos obtidos por extração com etanol pressurizado (PLE) seguindo um delineamento composto central rotacional com temperatura e tempo estático como variáveis independentes estudadas. Avaliou-se também o perfil de voláteis do óleo essencial, o teor de compostos fenólicos totais dos extratos etanólicos e as alterações causadas na matriz vegetal por diferentes processos de extração. Com a SFE conseguiu-se extrair toda a fração lipídica do fruto (2,33% &plusmn; 0,04.10-2%), a análise dos compostos voláteis do óleo essencial obtido permitiu inferir que este possui diversos compostos com potencial bioativo tais como E-cariofileno (17.56%), &alpha;-humuleno (16,26%) e &beta;-sesquifelandreno (14.27%); porém este óleo essencial não apresentou atividade antioxidante relevante. O extrato etanólico com maior rendimento (17, 49%) foi obtido a 74 °C por 6 min, mesma condição em que obteve-se a maior atividade antioxidante (EC50 = 6,37 mg/mL), porém o maior teor de compostos fenólicos totais (136,95 mg EGA/100 g de massa seca) foi obtido quando aplicou-se 60°C por 9 min. Em relação à atividade antimicrobiana, tanto os extratos obtidos por PLE quanto por SFE apresentaram atividade contra cepas de P. aeruginosa, S. aureus e B. cereus, somente extratos etanólicos apresentaram atividade contra cepas de L. monocytogenes e nenhum dos extratos apresentaram atividade contra cepas de B. subtilis, E. coli e Salmonella. Em ambos os extratos foi possível identificar compostos com potencial aplicação farmacológica. O estudo de processos de extração que envolvam inovação tecnológica na obtenção extratos com atividade biológica visa contribuir com o extrativismo consciente ou estimular o plantio em maior escala de mais um fruto tropical empregado na medicina popular brasileira. / The araçá is a fruit, belonging to the species Psidium grandifolium Mart. ex DC, native of the Brazilian Atlantic Forest, is not largely characterized by the scientific literature. This research work aimed to study the extraction yield and to evaluate the antioxidant and antimicrobial activities of the araçá essential oil obtained by supercritical carbon dioxide extraction (SFE) and the different extracts obtained by pressurized ethanol extraction (PLE) following a central composite design with temperature and static time as independent variables studied. It was also evaluated the volatile profile of the essential oil, the content of total phenolic compounds of the ethanolic extracts and the changes caused in the vegetal matrix by different extraction processes. SFE was able to extract the whole lipid fraction of the fruit (2.33% &plusmn; 0.04.10-2%), the analysis of the volatile compounds of the essential oil obtained allowed to infer that it has several compounds with bioactive potential such as E-caryophyllene (17.56%), &alpha;-humulene (16.26%) and &beta;-sesquipelandene (14.27%); but this essential oil had no relevant antioxidant activity. The highest ethanolic extract (17, 49%) was obtained at 74 °C for 6 min, the same condition in which the highest antioxidant activity was obtained (EC50 = 6.37 mg/mL), but the higher content of total phenolics contente (136.95 mg EGA / 100 g dry mass) was obtained when 60 °C was applied for 9 min. In relation to the antimicrobial activity, both extracts obtained by PLE and SFE showed activity against P. aeruginosa, S. aureus and B. cereus strains, only ethanolic extracts showed activity against L. monocytogenes strains and none of the extracts presented activity against B. subtilis, E. coli and Salmonella strains. In both extracts it was possible to identify compounds with potential pharmacological application. The study of extraction processes that involve technological innovation in obtaining extracts with biological activity aims to contribute to the conscious extraction or stimulate the larger scale cultivation of another tropical fruit used in Brazilian popular medicine.
26

Amélioration de la production halieutique des trous traditionnels à poissons (whedos) du delta de l’Ouémé (sud Bénin) par la promotion de l’élevage des poissons-chats Clarias gariepinus et Heterobranchus longifilis

IMOROU TOKO, Ibrahim 19 December 2007 (has links)
La présente étude s’inscrit dans une approche perspective d’augmentation de la production halieutique nationale par l’amélioration des techniques piscicoles déjà existantes, notamment les trous traditionnels à poissons (whedos), dans le delta du fleuve Ouémé (sud Bénin). Les premières approches de nos investigations montrent que, sur le plan socio-économique, l’augmentation de la productivité des whedos s’avère nécessaire pour l’amélioration des conditions de vie des pêcheurs dans la Vallée de l’Ouémé. En effet, avec le mode actuel de gestion des whedos, le revenu net par hectare et par an peut varier entre 182.000 et 572.000 Fcfa. Il représente au niveau actuel environ 27 % des revenus totaux de la pêche par ménage. Cependant, avec la mise en charge et l’alimentation artificielles d’espèces piscicoles adaptées, telles que les poissons-chats Clarias gariepinus et Heterobranchus longifilis, des rendements annuels de 3 à 36 t ha-1 peuvent être obtenus en fonction des densités d’élevage (respectivement de 4 à 24 poissons m-3). Les revenus nets provenant d’une telle gestion sont assez importants et peuvent varier en fonction de la densité de mise en charge, entre 1.664.000 et 31.675.000 Fcfa (respectivement de 4 à 24 poissons m-3). Ainsi, bien que la densité de 10,5 poissons m-3 soit apparue comme étant idéale pour l’optimisation des performances zootechniques, la recherche du profit maximal nous amène à suggérer pour la promotion de l’élevage de C. gariepinus dans les whedos, l’utilisation des densités plus élevées (environ 24 poissons m-3) afin de maximiser leurs capacités de production. Par ailleurs, la nécessité de production massive d’alevins de ces poissons-chats s’est avérée indispensable pour la promotion effective de leur élevage en whedos. A cet effet, nous avons évalué quelques aspects de l’élevage larvaire de ces espèces (âge de sevrage et densité de stockage), de même que les effets zootechniques et nutritionnels de différents régimes à base des tourteaux de soja et de coton aussi bien chez les larves que les juvéniles. Il ressort de ces études que le sevrage des larves de H. longifilis, maintenues à des densités de 10 à 25 individus L-1, est nécessaire entre les jours 5 et 8 post-éclosion afin d’optimiser aussi bien les performances zootechniques qu’économiques de l’élevage. D’autre part, le tourteau de soja s’est avéré plus efficace que celui de coton aussi bien chez les larves que les juvéniles de ces poissons-chats. Cependant, la présence des facteurs antinutritionnels, notamment l’acide phytique, limite les niveaux d’utilisation de ces tourteaux dans les régimes, étant donné que chez les juvéniles des réductions significatives des teneurs corporelles en minéraux, notamment en P, Zn et Mn ont été observées avec les régimes contenant jusqu’à 60 % de ces tourteaux. The present study aims to appraise the perspectives to increase the national fish production by improving the existing fish production systems, as the traditional fish pond (whedos), in the Ouémé River delta (southern Benin). The first approaches of our investigations show that, on the socio-economic level, the increase in the productivity of the whedos seems necessary to improve the livelihood conditions of the fishermen in the Ouémé Valley. Indeed, with the current mode of management of these whedos, we have observed that the net income per hectare can vary between 182,000 and 572,000 Fcfa. It represents, at the current level, approximately 27 % of the total incomes of fishing per household. However, by artificial stocking with adapted fishes, such as the catfishes Clarias gariepinus and Heterobranchus longifilis, and feeding, the annual outputs from 3 to 36 t ha-1 can be reached according to the stocking densities (from 4 to 24 fish m-3, respectively). The nets incomes generated from such management are rather important and can vary according to the stocking densities from 1,664,000 to 31,675,000 Fcfa (from 4 to 24 fish m-3, respectively). Although the density of 10.5 fish m-3 seemed ideal for the optimization of zootechnical parameters, the search of maximum profit leads us to suggest the higher densities (approximately 24 fish m3) for rearing African catfish in the whedos. Moreover, to improve the knowledge of these catfishes fingerlings production, we evaluated some aspects of the larval rearing (weaning time and stocking density), just as the nutritional effects of various diets, based on soybean or cottonseed meals, in the larvae as well as in the juveniles. It arises from these studies that, the weaning of H. longifilis larvae maintained at the densities from 10 to 25 L-1, is necessary between days 5 and 8 posthatch in order to optimize the zootechnical and economical performances of the rearing. Furthermore, we have observed that soybean meal was more effective than cottonseed meal in the larvae as well as in the juveniles. However, the presence of antinutrients factors, particularly the phytic acid, limit the levels of inclusion of these oilseed meals in the diets, since in juveniles, significant reductions of the body minerals contents, particularly P, Zn and Mn, were observed with the diets containing up to 60 % of these plants ingredients.
27

Crescimento vegetativo, potencial produtivo e qualidade dos frutos de macieiras tratadas com reguladores de crescimento / Vegetative growth, yield potential and fruit quality of apple trees sprayed with plant growth regulators

Silveira, João Paulo Generoso 22 July 2011 (has links)
Made available in DSpace on 2016-12-08T16:44:38Z (GMT). No. of bitstreams: 1 PGPV11MA076.pdf: 421773 bytes, checksum: 6fbf2a3579e5da5aa39372d361a40b76 (MD5) Previous issue date: 2011-07-22 / The aim of this study was to evaluate effects of spraying apple trees with prohexadione-calcium (ProCa) (na inhibitor of gibberellins synthesis) and gibberellin (GA&#8323;) on vegetative growth, yield potential, fruit quality, and occurrence of bitter pit in the fruit. The experimente was conducted in na orchard located in São Joaquim, Santa catarina State (Southern Brazil), in 2009/2010. catarina and Fuji apple trees were sprayed with water (control), ProCa and gibberellin (both products at the dose of 319 mg L¯¹), at the petal fall stage (October 15, 2009), when shoots were 5-10 cm long, with treatments repeated after 20 days. Leaves were assessed (in termsmof chlorophyll contente, área, dry mater and specific área) in January/2010, and length of current season shoots and weight of shoots removed by winter pruning were assessed in May/2010. The number of flower buds ando f fruit per flower bud were assessed in October/2009 and November/2010, respectively. Fruit were harvest at comercial maturity and then assessed for percentage of red skin área, skin color, density, weight, skin and pulp textures, flesh firmness, titratable acidity (TA), solids soluble contente (SSC) and starch index. Fruit were cold stored (0±0.5°C/90-95% RH) for four months, followed seven days for simulate marketing (20±4°C/60-70% RH) for four months, same evaluation carried out at harvest, as well as for incidence (%) and index of bitter pit. Trees treated with ProCa had higher leaf chlorophyll contente and lower specific leaf área in Fuji , lower leaf área in Catarina , lower shoot growth in both cultivars, and lower weight of shoots removed by winter pruning in Catarina , in the year following the treatment of the trees, both cultivars sprayed with ProCa had lower fruit set. the ProCa incresead the red color in Catarina apples. At harvest, the force for pulp penetratoon in the red side of the fruit was incresead in apple trees of both cultivars sprayed with ProCa. After cold stored, Fuji apples of trees sprayed with GA&#8323; had lower flesh firmness, while Catarina apples of trees sprayed with ProCa had higher firmness. Fruit Ca contente was not diferente between ProCa and GA&#8323; and between ProCa e the control in both cultivars. Fuji apples from trees treated with ProCa had lower N/Ca ratio in the skin tissue. Teh treatment with ProCa incresead the flesh firmness in the reddish fruit side and reduced the index of bitter pit during cold storage in both cultuivars. The use of ProCa in apples orchards might represent a new technology to reduce trees vegetative growth and the occurrence of bitter pit in the fruit. The GA&#8323; sprayed after full bloom increases trees vegetative growth and might cause changes in fruit quality atributes, leading to advanced maturiry, as well as increases the development of bitter pit / Este trabalho foi desenvolvido com o objetivo avaliar os efeitos da pulverização de macieira com um inibidor da síntese de giberelinas, o prohexadiona-cálcio (ProCa), e com giberelina (GA&#8323;), no crescimento vegetativo e potencial produtivo das plantas, e na qualidade e ocorrência de bitter pit nos frutos. O experimento foi conduzido em um pomar localizado no município de São Joaquim, SC, na safra 2009/2010. Macieiras Catarina e Fuji foram pulverizadas com água (tratamento controle), ProCa e GA&#8323; (ambos os produtos na dose de 319 mg L¯¹), na queda das pétalas (15/10/2009), quando as brotações do ano estavam com 5-10 cm de comprimento, sendo repetidas após 20 dias. Foram feitas avaliações foliares (teor de clorofila, área, matéria seca e área específica), em janeiro/2010, e de comprimento dos ramos do ano e de peso dos ramos podados, em maio/2010. A contagem dos cachos florais e do números de frutos por cacho floral ocorreram em outubro/2009 e novembro/2010, respectivamente. A colheita foi realizada na maturação comercial, ocasião em que foram feitas análises nos frutos do índice de cor vermelha, cor da epiderme, densidade, peso, atributos de textura (força para a penetração da casca e força para a penetração da polpa), firmeza de polpa, acidez titulável, sólidos solúveis totais (SS) e índice de iodo-amido. Os frutos foram armazenados em câmara fria convencional (0±0,5°C/90-95% UR), durante quatro meses, seguido de sete dias de comercialização simulada (20±4°C/60-70 UR), e após submetido as mesmas avaliações feitas na colheita, bem como de incidência (%) e índice de bitter pit . O tratamento com ProCa aumentou o teor de clorofila e reduziu a área foliar específica em macieira Fuji , reduziu a área foliar em Catarina , reduziu o comprimento dos ramos do ano nas duas cultivares e o peso dos ramos podados em Catarina . No ano subsequente ao da aplicação dos tratamentos, macieiras pulverizadas com o ProCa, de ambas as cultivares, apresentaram menor frutificação. O tratamento com ProCa proporcionou maior coloração vermelha em maçãs Catarina . No momento da colheita, maçãs Fuji e Catarina provenientes de plantas pulverizadas com ProCa apresentaram maior força para a penetração da polpa no lado mais vermelho dos frutos. Após o armazenamento, maçãs Fuji de plantas pulverizadas com GA&#8323; apresentaram menor firmeza de polpa e maçãs Catarina de plantas pulverizadas com ProCa apresentaram maior firmeza de polpa. O teor de Ca nos frutos não diferiu entre os tratamentos ProCa e GA&#8323; e entre ProCa e controle, em ambas as cultivares. Maçãs Fuji apresentaram menor relação N/Ca no tecido da casca quando pulverizadas com ProCa. O tratamento com ProCa proporcionou aumento na firmeza no lado mais vermelho do fruto e reduziu o índice de bitter pit durante o armazenamento refrigerado em ambas as cultivares. A utilização do ProCa na cultura da macieira pode ser uma nova alternativa para o controle do crescimento vegetativo de da manifestação do bitter pit nos frutos. O GA&#8323;, pulverizado em pós-floração, em macieiras aumenta o crescimento vegetativo e pode ocasionar algumas modificações nos atributos de qualidade nos frutos, indicando um avanço na maturação, e na manifestação do bitter pit
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Primary Sediment Production from Granitic Rocks in Southeastern Arizona

Acaba, Joseph Michael January 1992 (has links)
Isolated granitic rock bodies (granites, granodiorites, quartz monzonites) in the vicinity of Benson in southeastern Arizona were studied to trace the behavior of rock weathering. Thin sections of fresh granites were examined to characterize the original mineralogy which consisted mainly of quartz, feldspars, and micas. The weathering products show up on the granites as grus and soil profiles as well as down slope in the basin deposits. X -ray diffraction studies of the < 2 micrometers fraction of the weathering products proved illite, smectite, illite-smectite mixed layer, and kaolinite to be the dominant clays; quartz and feldspar also persisted into this size fraction. Silt sized material produced similar results. The quartz monzonite of Texas Canyon afforded a special study of the initial weathering stages of feldspars and micas. In the < 2 micrometers fraction obtained from granitic material placed in an ultra sonic bath, the feldspars weathered to a Na-montmorillinite while biotite weathered to vermiculite.
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Infra-Red Spectrophotometry and X-Ray Diffractometry as Tools in the Study of Nickel Laterites

Azevedo, Luiz Otavio Roffee January 1985 (has links)
Nickel silicate laterite deposits developed on ultra-mafic rocks are similar in many general respects but they vary considerably in detail. The mineralogy of these surficial deposits is very complex and difficult to determine because of the fine grained nature and solid solution characteristics of the hydrous secondary minerals and because many of the phases are actually mineraloids that are poorly ordered or amorphous. To try some new approaches toward clarification of these phases, 24 samples from New Caledonia and Puerto Rico ranging from the ophiolite-ultramafic olivine-pyroxene-chromite-serpentine substrate rocks upward through intermediate phases of weathering to the final oxide -hydroxide iron cap phase were analyzed with the infrared spectrophotometer (IR -10) and with the automated X –ray diffractometer. Four limonite samples were also mineralogically analyzed. Goethite, secondary quartz, cryptomelane, hematite, chromite, talc, thuringite, and garnierite have been identified in various samples as weathering profile products.
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Réduire le potentiel acidifiant des fromages pour améliorer leurs fonctionnalités nutritionnelles : identification des leviers biochimiques et perspectives technologiques / Reducing the acid-forming potential of cheeses to improve their nutritional features : identification of biochemical levers and technological perspectives

Gore, Ecaterina 05 July 2016 (has links)
Une caractéristique nutritionnelle peu connue des fromages est leur potentiel acidifiant, qui se révèle au cours du métabolisme et, à long terme, est susceptible d’induire des effets délétères sur la santé du consommateur. Malgré des conséquences physiopathologiques bien connues, très peu d’études se sont intéressées au potentiel acidifiant/alcalinisant des aliments et aucune à celui des fromages. L’objectif principal était d’évaluer d’une part le potentiel acidifiant des fromages et identifier ses déterminants au cours de la fabrication et d’autre part d’explorer des stratégies d’optimisation technologique permettant de réduire le potentiel acidifiant des fromages, tout en assurant leurs qualités gustatives. Le potentiel acidifiant a été évalué sur la base de l’indice PRAL (Potential Renal Acid Load, en tenant compte des teneurs en protéine, P, Cl, Na, K, Mg et Ca) et de la teneur en anions organiques (lactate et citrate). Dans un premier temps, l’étude du potentiel acidifiant de cinq types de fromages du commerce a permis d’établir un lien fort entre le type du fromage et son potentiel acidifiant. L’indice PRAL le plus faible est celui du fromage frais avec - 0,8 mEq/100 g, les indices les plus élevés atteignant 25,3 mEq/100 g pour le fromage à pâte pressée non-cuite (Cantal) et 28,0 mEq/100 g pour le fromage à pâte persillée (Fourme d’Ambert). Ce positionnement a ainsi permis de sélectionner un modèle fromage pour la suite des travaux : la Fourme d’Ambert. Dans une seconde phase, l’égouttage et le salage ont été identifiés comme les deux étapes technologiques déterminantes dans la génération du potentiel acidifiant du modèle fromage choisi, au cours de la transformation fromagère, suivie en milieu industriel. Ces études démontrent un déséquilibre important entre les éléments acidifiants (Cl, P, protéines) et les éléments alcalinisants majeurs (Na et Ca) du PRAL. En particulier, les Cl suivis par le P, ont exercé un très fort impact expliquant les indices élevés obtenus. Enfin, une substitution du NaCl par des sels organiques de calcium (lactate et citrate de Ca) a été testée en conditions industrielles pendant le salage à sec de la Fourme d’Ambert. Les deux sels ont montré un réel intérêt pour substituer partiellement le sel des fromages, sans affecter les propriétés sensorielles des produits finis et notamment les saveurs salée et amère. La substitution au lactate de Ca permettrait d’optimiser le potentiel acidifiant des fromages, en diminuant le PRAL et la teneur en Na et en augmentant la teneur en lactate. La substitution au citrate de Ca serait plutôt indiquée dans le cadre d’un enrichissement en Ca. En conclusion, ces études ont permis d’identifier les leviers à maîtriser pour réduire le potentiel acidifiant des fromages. L’approche adoptée a proposé la mise en application d’un concept connu principalement des nutritionnistes jusqu’ici dans les domaines de la biochimie et de la technologie alimentaires. Les perspectives d’innovation envisagées sont pertinentes avec les enjeux de santé publique actuels, en visant la réduction en Na dans les fromages et en participant à la limitation de l’acidose métabolique latente induite par les régimes occidentaux. Enfin, les retombées économiques de ces recherches sont prometteuses pour les filières fromagères. / A disregarded nutritional feature of cheeses is their acid-forming potential when ingested, associated with deleterious effects for consumers’ health. Despite the well-known pathophysiological consequences, very few studies investigated the acidifying/alkalizing potential of foods and especially, none targeted cheeses. The research project aimed on the one hand to evaluate the acid-forming potential of cheeses and identify the main key steps of the manufacture involved in this phenomenon and on the other hand to explore technological optimization strategies to reduce the acid-forming potential of cheeses, without altering their sensory properties. The acid-forming potential was evaluated on the basis of their Potential Renal Acid Load (PRAL) index (considering protein, P, Cl, Na, K, Mg and Ca contents) and organic anions contents (lactate and citrate). Firstly, the study of the acid-forming potential of five commercial cheeses from different cheese-making technologies established a strong link between the type of cheese and their acid-forming potential. PRAL index ranged from - 0.8 mEq/100 g for fresh cheese to 25.3 mEq/100 g for hard cheese (Cantal) and 28.0 mEq/100 g for the blue-veined cheese Fourme d’Ambert. This positioning allowed to select Fourme d'Ambert as model cheese for next steps. Secondly, draining and salting were identified as the main key steps responsible for the generation of the acid-forming potential of the model cheese, by following an industrial cheese-making process. These studies emphasized a great imbalance between acidifying elements of PRAL calculation (Cl, P and proteins elements) and alkalinizing ones (Na and Ca). Particularly, Cl followed by P elements had a strong impact on the PRAL value. Finally, the salt substitution with organic calcium salts (calcium lactate and calcium citrate) was tested under industrial conditions during the dry salting of Fourme d'Ambert cheese. Both salts showed a real nutritional interest to partially replace salt in cheese, without affecting their sensory properties and especially the salty and the bitter flavors. The salt substitution by calcium lactate could reduce the acid-forming potential of cheeses, by decreasing the PRAL and the sodium content and by increasing the lactate content. The calcium citrate substitution would rather be recommended for Ca enrichment of cheeses. As a conclusion, these studies allowed to identify technological solutions to reduce the acid-forming potential of cheeses. The adopted approach proposed the implementation of a concept, known mainly by nutritionists so far, to the biochemistry and the food technology fields. The considered prospects for innovation are relevant with the current public health issues, targeting the reduction of Na in cheeses and participating in the limitation of the Western diets induced metabolic acidosis. Finally, the economic benefits of this research are promising for cheese-making producers.

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