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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.
201

Who's Your Daddy? A Study of Extra-Pair Copulation and Mating Behaviors of Protonotaria citrea

Heidrich, Morton Catherine 06 December 2013 (has links)
Mating behavior has a profound impact on reproductive success and the resulting genetic structure of offspring. Extra-pair copulation is a widely observed behavior within avian species. This study explored the genetic effects of mating behaviors of Prothonotary warblers, Protonotaria citrea (Parulidae), using co-dominant microsatellite markers. Prothonotary warblers are migratory songbirds that build nests in cavities, commonly found in wetland habitats. A set of artificial nest boxes were initiated by Dr Robert Reilly in 2002 in Dutch Gap, Chesterfield County Virginia, USA, a tidal tributary off the James River. From this population, 28 nest boxes were surveyed yielding 47 adults and 110 offspring. All individuals were genotyped and the multilocus genotypes were used to identify parentage. Using paternity exclusion, 27.2% of offspring were identified as resulting from extra-pair mating. Surprisingly, an additional 11.8% of offspring were classified as genetically unrelated to the resident female, being presumably the result of an egg dumping from a female not caught at the nest box. The vast majority of nest boxes, 82.1% in this study, had at least one offspring that was a result of a mating behavior outside of the social pair. There was also positive spatial autocorrelation in extra-pair paternity suggesting that these matings are not randomly distributed across the sampling landscape. These data show that Protonotaria citrea engage in both extra-pair copulations and nest parasitism. Whether this is normal mating behavior for the species, or something that is unique to this population is unknown.
202

Caractérisation et complémentarité des facteurs de virulence du parasitoïde Hyposoter didymator (Ichneumonidae) / Characterization and complementarity of the virulence factors in the ichneumonid wasp Hyposoter didymator

Dorémus, Tristan 22 March 2013 (has links)
Les Hyménoptères parasitoïdes ont un développement larvaire s'effectuant au détriment d'un organisme hôte. Pour exploiter au mieux la ressource que représente un hôte arthropode dont la biologie peut présenter certains obstacles tels que la mobilité et le système immunitaire, les parasitoïdes ont développé une diversité modes de vie et de stratégies de virulence. Ce manuscrit replace les parasitoïdes dans leur contexte évolutif afin de mieux comprendre la diversité surprenante de leurs modes de vie. Ces modes de vie conditionnent la nature des interactions dans les systèmes hôte/parasitoïde. Nous verrons comment, par l'utilisation de nombreux facteurs de virulence tel que le venin, les polydnavirus et bien d'autres encore, les parasitoïdes manipulent la physiologie de leur hôte afin de le rendre adéquat à leur propre développement. Ce travail s'est intéressé au modèle endoparasitoïde Hyposoter didymator (Hym., Ichneumonidae). Nous avons ainsi caractérisé les protéines produites dans la glande à venin des femelles et identifié l'ensemble des gènes du polydnavirus associé (HdIV; H. didymator Ichnovirus), grâce à des techniques de protéomique, génomique et transcriptomique. Nous avons également suivi et quantifié les altérations de la physiologie de l'hôte Spodoptera frugiperda au cours du parasitisme et évalué le rôle relatif de différents facteurs dans ces perturbations et dans la réussite parasitaire. Nos résultats ont permis de montrer que seul le fluide du calice contenant HdIV est nécessaire au développement du parasitoïde. En parallèle, nous avons mis à jour une propriété immuno-évasive des œufs d'H. didymator liée à des protéines associées à l'exochorion. L'ensemble de ce travail a permis de dessiner un élégant schéma expliquant la complémentarité spatio-temporelle des facteurs de virulence durant le parasitisme. Finalement, nous avons cherché à mieux comprendre le déterminisme du spectre d'hôte d'H. didymator, ce qui nous a conduit à montrer que les deux stratégies de contournement de la réponse immunitaire (immuno-évasion et infection virale) se révèlent inefficaces chez les hôtes non-permissifs. / Parasitic wasps must deal with physiological features of their host such as mobility, an efficient immune system and a variable metabolism. To ensure successful parasitism in a large range of arthropod hosts, parasitoids display a huge diversity of lifestyle and rely in a variety of virulence factors. In this document, we introduce parasitoid lifestyle in an evolutionary context in order to better understand the parasitoid complexity. As the parasitoid lifestyle drives the host/parasitoid interaction outcome, we discuss for all how the virulence factors such as venom, polydnaviruses and many others are used to ensure successful development of the parasitoid. In this study, we focused on the endoparasitoid Hyposoter didymator (Hym., Ichneumonidae) virulence factors. We thus identified venom proteins and the genes from the associated polydnavirus, HdIV using proteomics, genomics and transcriptomics approaches. Studies on the effect of the venom and the calyx fluid containing the polydnavirus HdIV, reveal that only the calyx fluid is necessary for Spodoptera frugiperda host physiological alteration and parasitism success. Futhermore, this work presents the discovery of a local immune-evasive property of the H. didymator egg exochorion. All these data permitted us to design an effective spatio-temporal model of the virulence factor complementarity used by H. didymator during the parasitism time course. Finally, studies on the H. didymator host range reveals the inefficiency of the different virulence factors in non-permissive hosts, opening insights on the host permissiveness molecular mechanisms.
203

Automatic assessment of biological control effectiveness of the egg parasitoid Trichogramma bourarachar against Cadra cautella using machine vision

Song, Yuqi January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Naiqian Zhang / The primary objective of this research is to achieve automatic evaluation of the efficiency of using Trichogramma bourarachae for biological control of Cadra (=Ephestia) cautella by calculating the rate of parasitization. Cadra cautella is a moth feeding as a larva on dried fruit as well as stored nuts, seeds, and other warehouse foodstuffs. It attacks dates from ripening stages while on tree, throughout storage, and until consumption. These attacks cause significant qualitative and quantitative damages, which negatively affect dates’ marketability, resulting in economic losses. To achieve this research goal, tasks were accomplished by developing image processing algorithms for detecting, identifying, and differentiating between three Cadra cautella egg categories based on the success of Trichogramma parasitization against them. The egg categories were parasitized (black and dark red), fertile (unhatched yellow), and hatched (white) eggs. Color, intensity, and shape information was obtained from digital images of Cadra eggs after they were subjected to Trichogramma parasitization and used to develop detection algorithms. Two image processing methods were developed. The first method included segmentation and extractions of color and morphological features followed by watershed delineation, and is referred to as the "Watershed Method" (WT). The second method utilized the Hough Transformation to find circular objects followed by convolution filtering, and is referred to as the "Hough Transform Method" (HT). The algorithms were developed based on 2 images and then tested on more than 40 images. The WT and the HT methods achieved correct classification rates (CCRs) of parasitized eggs of 92% and 96%, respectively. Their CCRs of yellow eggs were 48% and 94%, respectively, while for white eggs the CCRs were 42% and 73%. Both methods performed satisfactorily in detecting the parasitized eggs, but the HT outperformed the WT in detecting the unparasitized eggs. The developed detection methods will enable automatic evaluation of biological control of Cadra (=Ephestia) cautella using Trichogramma bourarachae. Moreover, with few adjustments these methods can be used in similar applications such as detecting plant diseases in terms of presence of insects or their eggs.
204

Regulation of DNA Double Strand Break Response

Chen, Chen January 2014 (has links)
<p>To ensure genomic integrity, dividing cells implement multiple checkpoint pathways during the course of the cell cycle. In response to DNA damage, cells may either halt the progression of the cycle (cell cycle arrest) or undergo apoptosis. This choice depends on the extent of damage and the cell's capacity for DNA repair. Cell cycle arrest induced by double-stranded DNA breaks relies on the activation of the ataxia-telangiectasia (ATM) protein kinase, which phosphorylates cell cycle effectors (e.g., Chk2 and p53) to inhibit cell cycle progression. ATM is an S/T-Q directed kinase that is critical for the cellular response to double-stranded DNA breaks. Following DNA damage, ATM is activated and recruited to sites of DNA damage by the MRN protein complex (Mre11-Rad50-Nbs1 proteins) where ATM phosphorylates multiple substrates to trigger a cell cycle arrest. In cancer cells, this regulation may be faulty and cell division may proceed even in the presence of damaged DNA. We show here that the RSK kinase, often elevated in cancers, can suppress DSB-induced ATM activation in both Xenopus egg extracts and human tumor cell lines. In analyzing each step in ATM activation, we have found that RSK disrupts the binding of the MRN complex to DSB DNA. RSK can directly phosphorylate the Mre11 protein at Ser 676 both in vitro and in intact cells and can thereby inhibit loading of Mre11 onto DSB DNA. Accordingly, mutation of Ser 676 to Ala can reverse inhibition of the DSB response by RSK. Collectively, these data point to Mre11 as an important locus of RSK-mediated checkpoint inhibition acting upstream of ATM activation.</p><p>The phosphorylation of Mre11 on Ser 676 is antagonized by phosphatases. Here, we screened for phosphatases that target this site and identified PP5 as a candidate. This finding is consistent with the fact that PP5 is required for the ATM-mediated DNA damage response, indicating that PP5 may promote DSB-induced, ATM-dependent DNA damage response by targeting Mre11 upstream of ATM.</p> / Dissertation
205

The performance of the seed feeding bruchid beetle Sulcobruchus subsuturalis (Pic) (Cleoptera: Bruchidae) in the biological control of Caesalpinia decapetala (Roth) Alston (Fabaceae) an invasive weed in South Africa

Kalibbala, Faith Nandawula 25 March 2009 (has links)
The release of the seed eating beetle Sulcobruchus subsuturalis for biological control of Caesalpinia decapetala in South Africa has been ongoing since 2000. This is the first post release evaluation of the efficacy of the agent against the weed. The study assessed the phenology of C. decapetala and S. subsuturalis at two sites and included determining the establishment of the beetle on the target weed at 25 study sites. In addition, the effects of S. subsuturalis on seed densities as well as seed germination and seedling recruitment were examined. Furthermore predation by native ants and attacks by native parasitoids were also examined at two release sites. Mature filled pods were available on the tree from September (spring) to March (summer) when the beetle is expected to be reproductively active. The majority of beetle releases by Working for water took place in summer. However the proportion of beetle infested seeds, which were only recovered inside pods in the tree canopy at study sites, was low (0 to 15.5%). Consequently high seed densities and seedling recruitment were observed in the field. In the laboratory, S. subsuturalis did not lay eggs on buried seeds, however seed infestation levels were generally high. Only 8.3% of the seeds containing adults germinated and 6.3% emerged into seedlings. Of the seeds containing larvae, only 14.6% germinated and 2.1% emerged into seedlings. Thus far, S. subsuturalis has failed to maintain high populations on the target weed, possibly due to egg predation by native ants (Crematogaster species, Pheidole megacephala, Messor natalensis and Tetramorium avium) and attacks by native parasitoids. Egg predation reached 100% within 10 days. Egg parasitism by unknown parasitoids ranged between 80 and 93.1% in Limpopo. The parasitic wasp Dinarmus altifrons was recovered once developing inside a C. decapetala seed infested with S. subsuturalis. Further investigations regarding attacks by indigenous parasitoids on S. subsuturalis are required to determine the extent of this problem. Meanwhile releases of S. subsuturalis against C. decapetala should continue. However release efforts need to be improved by (a) using inundative rather than inoculative releases (b) Releasing every year between September and March (summer) and (c) involving land owners, farmers and nature reserve authorities in release activities. Ultimately an additional agent should be sought for release against C. decapetala as the weed may not be the preferred host for S. subsuturalis.
206

Iluminação para poedeiras comerciais

Ouros, Caio César dos. January 2019 (has links)
Orientador: Edivaldo Antonio Garcia / Resumo: Com o objetivo de atualizar as informações relacionadas ao fornecimento de luz para as poedeiras comerciais modernas visando racionalizar o uso da energia elétrica nos sistemas de produção de ovos com manutenção ou melhoria do desempenho produtivo e qualidade dos ovos, foram realizados três experimentos. Em cada experimento foram utilizadas 480 aves da linhagem Lohmann LSL® distribuídas em delineamento em blocos casualizados com quatro tratamentos e seis repetições de 20 aves cada. O experimento I foi realizado para avaliação do efeito do comprimento do fotoperíodo sendo: fotoperíodo 1 - 14 horas de luz e 10 horas de escuro (14L:10E); fotoperíodo 2 – 15 horas de luz e 9 horas de escuro (15L:9E); fotoperíodo 3 – 16 horas de luz e 8 horas de escuro (16L:8E); fotoperíodo 4 – 17 horas de luz e 7 horas de escuro (17L:7E). No experimento II foram testadas quatro iluminâncias: T1 – 5 lux; T2 – 10 lux; T3 – 15 lux; T4 – 20 lux. O fotoperíodo adotado foi o de 14L:10E que proporcionou o melhor resultado no experimento I. O experimento III foi realizado para avaliação de quatro programas de luz: contínuo (controle) – consistiu de um fotoperído único; intermitente 1 – consistiu no fornecimento de 1 hora de luz, uma hora antes do início fotoperíodo natural (manhã); intermitente 2 – consistiu no fornecimento de 30 minutos de luz, uma hora antes do início do fotoperiodo natural; intermitente 3 – consistiu no fornecimento de 15 minutos de luz, uma hora antes do início do fotoperíodo natural.... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
207

Fibra na dieta de poedeiras comerciais / Fiber in the diet of commercial laying hens

Leite, Brunna Garcia de Souza 24 August 2018 (has links)
O objetivo desse estudo foi avaliar o efeito da inclusão de fibra na dieta de poedeiras comerciais. Para tanto, foram utilizadas 416 poedeiras comerciais, da linhagem Lohmann LSL, distribuídas em um delineamento inteiramente casualizado em quatro tratamentos com 13 repetições de oito aves em cada unidade experimental. Os níveis de fibra estudados consistiram em dietas com a inclusão de 0,0; 0,2; 1,0 e 2,0% de uma fonte comercial de fibra. O período experimental foi conduzido da 24ª a 40ª semana de idade das poedeiras, totalizando quatro ciclos de 28 dias cada. Os dados de desempenho produtivo (produção de ovos, consumo de ração, peso e massa de ovos, conversão alimentar por dúzia e por massa de ovos e percentagem de ovos vendáveis) e a qualidade de ovos (resistência da casca, coloração da gema, altura de albúmen, unidade Haugh e espessura de casca) foram avaliados ao final de cada ciclo de 28 dias. No final do experimento, uma ave por unidade experimental foi separada, para a obtenção dos dados de morfometria intestinal, em que foi retirado o trato intestinal para as avaliações de peso de moela, comprimento de intestino e altura das vilosidades e profundidade de cripta dos segmentos (duodeno, jejuno e íleo). Os dados experimentais do desempenho produtivo obtidos pela média do período experimental foram utilizados para a realização da análise econômica. Observou-se que no desempenho produtivo, os níveis de inclusão de 1,0 e 2,0% de fibra na dieta promoveram efeito significativo positivo sobre o peso e massa de ovos. Na qualidade de ovos os diferentes níveis de fibra apresentaram melhora sobre a resistência e espessura de casca. Na análise de morfometria intestinal observou que as aves alimentadas com diferentes níveis de fibra na dieta obtiveram maior comprimento de intestino, maior altura de vilosidade no jejuno e melhor relação altura da vilosidade:profundidade de cripta no íleo. Em relação à análise econômica o nível de inclusão de 0,2% de fibra na dieta obteve resultados iguais aos da dieta controle sobre custo total, custo total por ave e entre o custo total sobre a renda total. Concluindo-se que a inclusão de 1,0 e 2,0% de fibra na dieta de poedeiras pode causar efeitos positivos sobre os parâmetros de desempenho produtivo, qualidade de ovos e no desenvolvimento da mucosa intestinal. E pelo ponto de vista econômico a inclusão de 0,2% de fibra na dieta é mais viável. / The aim of this study was to evaluate the effect of fiber inclusion on the diet of laying hens. Therefore, 416 commercial laying hens of the Lohmann strain were distributed in a completely randomized design in four treatments with thirteen replicates of eight birds per experimental unit. The fiber levels studied consisted of diets with inclusion of 0,0; 0.2; 1,0 and 2,0% from a commercial source of fiber. The trial was conducted from the 24th to 40th week of birds\' age, totaling 4 cycles of 28 days each. The data of productive performance (egg production, feed intake, egg weight and mass, feed conversion per dozen and egg mass and percentage of salable eggs) and egg quality (eggshell strength, yolk color, albumen height, Haugh unit and eggshell thickness) were evaluated at the end of each 28-day cycle. At the end of the experiment, one bird per experimental unit was separated to obtain the intestinal morphometry data, in which the intestinal tract was removed for gizzard weight, intestine length and villus height and crypt depth of the segments (duodenum, jejunum and ileum). The experimental data of the productive performance obtained by the mean of the experimental period were used for the accomplishment of the economic analysis. It was observed that in the productive performance, inclusion levels of 1,0 and 2,0% of dietary fiber promoted a significant effect on egg weight and egg mass. In the egg quality the different levels of fiber presented improvement on the resistance and thickness of the shell. In the analysis of intestinal morphometry, it was observed that the birds fed different levels of fiber in the diet obtained a longer intestine length, a higher villus height in the jejunum and a better villus height ratio: crypt depth in the ileum. Regarding the economic analysis, the inclusion level of 0.2% fiber in the diet obtained results equal to the control diet over feeding cost, feeding cost per bird and between feeding cost over total revenue. It was concluded that the inclusion of fiber in the laying diet can cause positive effects on parameters of productive performance, egg quality and intestinal mucosa development. And from the economic point of view the inclusion of 0.2% fiber in the diet is more viable.
208

Disponibilidade de ferro em ovo, cenoura e couve e em suas misturas / Iron availability in egg, carrot and cabbage and in them mixtures

Machado, Flavia Maria Vasques Farinazzi 26 October 2005 (has links)
A anemia causada por deficiência de ferro é a forma mais comum de todas as anemias e afeta grande parcela da população mundial, especialmente o grupo materno-infantil: lactentes, pré-escolares, escolares, gestantes e nutrizes. A carência acarreta atraso no desenvolvimento psicomotor e cognitivo de crianças menores de dois anos, além de diminuição da eficiência da função imune, e agravamento de doenças infecciosas. O presente estudo teve por objetivos avaliar a disponibilidade de ferro em alimentos fontes deste e de vitamina A, ovo (o), cenoura (c) e couve (cv), bem como verificar a interação do ferro com &#945; e ß-caroteno, e com outros interferentes. As misturas foram de ovo com cenoura e ovo com couve em diferentes proporções (1:1), (1:1,5), (1:2), (1:2,5) e (1:3) e também dos 3 alimentos sozinhos, totalizando 13 amostras. As amostras, após pré-preparo e cocção, foram submetidas às análises de composição centesimal, ferro, taninos, ácido fítico, ácido oxálico, &#945;- e &#946;- caroteno e ferro dialisável. Os dados foram submetidos à análise estatística empregando o teste de Tukey, regressão polinomial e correlação, utilizando o software SAS (1996). Os valores para umidade variaram de 83,93 a 95,74 g/100g, apresentando diferenças significativas entre as distintas amostras, assim como para proteínas (0,55 a 7,22g /100g) e extrato etéreo (0,21a 5,94 g/100g). Foi observado que em relação à umidade, extrato etéreo, proteínas, cinzas e &#946;-caroteno houve correlação significativa para o ferro dialisável, sendo que para umidade e &#946;-caroteno essa correlação foi positiva e para os demais componentes foi negativa. Os teores para taninos, fitatos e oxalatos variaram de 0,78 a 1,40 mEqcatequina/g, 0,17 a 0,42 mg/g, e 0,06 a 0,30% respectivamente. A amostra 2 (1o:1,5c) apresentou teores mais elevados de taninos (1,40 mEqcatequina/g), e as amostras 6 (1o:1cv) e 7 (1o:1,5cv) apresentaram teores mais elevados de oxalato e teores de ferro dialisável mais baixo, em relação às outras misturas. O teor de &#945;-caroteno para as amostras contendo cenoura variou de 2.435,27 a 4.609,83 µg/100g. Quanto ao &#946;-caroteno observou-se variações de 2.406,75 a 7.881,55 µg/100g, sendo evidenciado valores mais elevados para as amostras com cenoura. Numericamente, as misturas com maior proporção de cenoura e couve apresentaram os maiores resultados para o ferro dialisável, que variou entre 0,99 a 7,43%, sendo que a amostra 5 (1o:3c) apresentou o melhor resultado, seguida pelas amostras 1, 2, 3, 4, 8, 9 e 10. Pelos resultados obtidos pode-se concluir que as misturas com maior proporção de cenoura e couve aumentaram a disponibilidade do ferro, principalmente pelo maior conteúdo de ß-caroteno. Não houve interferência significativa dos antinutricionais sobre o ferro dialisável, embora os taninos e ácido oxálico atuaram como fatores limitantes quando observados os valores numéricos nas amostras com maiores concentrações de cenoura e couve. O ß-caroteno apresentou correlação positiva significativa com o ferro dialisável, exercendo influência na redução do efeito dos antinutricionais, especialmente dos fitatos, na disponibilidade do ferro, principalmente nas amostras com cenoura. Assim, pode ser recomendada a utilização de misturas de alimentos como ovo e cenoura, sendo que este último deve estar em maiores proporções em refeições destinadas a populações carentes em ferro. / The anemia caused by iron deficiency, is the form more common of all the anemias and it affects large portion of the world population, especially the maternal-infantile group: infants, child-school, children, pregnant woman and nutrizes, carting delay in the development psicomotor and cognitive of smaller children two years old, besides decrease of the efficiency of the immune function, and worsening of infectious diseases. This research aims to estimate the iron availability in food iron sources and vitamin A, egg (e), carrot (c) and cabbage (cb), as well as to verify the interaction of the iron with &#945;, ß-carotene and with other interferents, being mixed the foods in study, resulted 13 food mixtures in different proportions (1:1), (1:1.5), (1:2), (1:2.5) and (1:3) include three food alone. The food mixtures, after prepare and cooking, was submitted the analyses of centesimal composition, levels of iron, tannin, phytic acid, oxalic acid, &#945;, ßcarotene and in vitro iron dialysability. The statistical analysis was determinate by SAS System include polynomial regression and correlation. The values for moisture varied from 83.93 to 95.74 g/100g, showing significant differences among the different mixtures, as well as for proteins (0.55 to 7.22 g/100g) and fat (0.21 to 5.94 g/100g). There was significant correlation with regard to moisture, fat, protein, ash and ß-carotene to in vitro iron dialysability, being positive correlation to moisture and ß-carotene, and negative to other components. The levels of tannins, phytate and oxalates ranged 0.78 to 1.40 mEqcatequina/g, 0.17 to 0.42mg/g and 0.06 to 0.30%, respectively. The mixture 2 (1e:1.5c) showed high levels of tannins (1.40mEqcatequina/g), and the mixtures 6 (1e:1cb) and 7 (1e:1.5cb) high levels of oxalates, and lower levels of in vitro dialysability iron, in relation to the other mixtures. The values for &#945;- carotene to mixtures with carrot ranged 2,435.27 to 4,609.83 µg/100g. With regard to ß-carotene, ranged variations to 2,406.75 from 7,881.55 µg/100g, being observed higher levels for the mixtures with carrot. The numbers showed that the mixtures with larger carrot and cabbage proportion showed the bigger results for the in vitro dialysability iron, ranges to 0.99 from 7.43 %, and the sample 5 (1e:3cb) it presented the bigger value, proceeded by the mixtures 1, 2, 3, 4, 8, 9 and 10. It’s concluded that the mixtures with larger carrot and cabbage proportion increased the iron availability, especially for the largest content of ß-carotene. There was not significant interference of antinutritional in the in vitro iron dialysability, although tannins and oxalates were an inhibitor when observed the numeric values in the mixtures with larger carrot and cabbage concentrations. The ß-carotene showed significant positive correlation with in vitro iron dialysability, increasing influence in the reduction of the antinutritional factors effect, especially phytates, in the iron availability, mainly in the mixtures with carrot. Therefore, the use of food mixtures as egg and carrot can be recommended, and this last one should be in larger proportions in meals destined to lacking populations in iron.
209

Concentração de proteínas (fosvitina e lipovitelina) em gemas de ovos de galinhas (Gallus gallus) nos diferentes ciclos de postura e sua interferência na disponibilidade do ferro / Protein concentration (phosvitin and lipovitelin) in egg yolks of hens (Gallus gallus) in the different cycles of position and its interference in the availability of the iron

Sartori, Erika Vidal 28 August 2007 (has links)
O ovo é o produto de eficiente transformação biológica feita pela galinha (Gallus gallus) de postura, com alta qualidade nutricional para o consumo humano. Na gema do ovo encontra-se a proteína denominada fosvitina, a mesma atua como carreadora do ferro se ligando a ele. A deficiência de ferro ocorre normalmente devido ao consumo insuficiente de alimentos fontes de ferro ou a baixa biodisponibilidade. O objetivo desta pesquisa foi verificar a concentração de proteínas, em especial a fosvitina/lipovitelina presente em gemas de ovos crus e cozidos nos diferentes ciclos de postura (inicial, intermediário e final) e avaliar a interferência desta proteína na disponibilidade do micronutriente ferro. Os tratamentos foram realizados em diferentes períodos e utilizaram-se ovos crus e cozidos, sendo gemas cruas de poedeiras em início, meio e fim de postura e gemas cozidas nos três ciclos de postura. Foram realizadas as análises de composição centesimal, concentração de ferro total e dialisável, concentração de proteínas em gemas e eletroforese em gel de poliacrilamida (SDS-PAGE). Houve diferença na concentração de proteínas e diferentes níveis de ferro dialisável nos três ciclos de postura, porém em gemas cruas e cozidas. Com o passar dos ciclos (inicial, intermediário e final), as poedeiras mais velhas, apresentaram gemas com teor mais elevado de ferro disponível, porém uma quantidade inferior de proteínas em especial a fosvitina/lipovitelina, comparando-se com os ciclos inicial e intermediário. A disponibilidade de ferro foi mais elevada em gemas que passaram pelo processo de cocção, porém em poedeiras de postura final. / The egg is the product of efficient biological transformation made by the hens of position, with high nutricional quality for the human consumption. In the egg yolk of the egg it meets phosvitin called protein, the same one acts as hauled of the iron if binding it. The iron deficiency normally occurs due to the insufficient food consumption iron sources or low the bioavailability. The objective of this research was to verify the protein concentration, in special the present phosvitin/lipovitelin in egg yolks of raw eggs and stews in the different cycles of position (initial, intermediate, end) and to evaluate the interference of this protein in the availability of the micronutrient iron. The treatments had been carried through in different periods and had used raw eggs and cooked, being raw egg yolks of hens in initial, intermediate and end of position and egg yolks boil in the three cycles of position. The analyses of proximal composition had been carried through, concentration of total and availability iron, protein concentration in egg yolks and electrophoresis in poliacrilamide (SDS-PAGE) were carried. It had difference in the protein concentration and different levels of iron availability in the three cycles of position, however in raw and boiled egg yolks. With passing of the cycles (initial, intermediate, end), the hens oldest, had more presented egg yolks with a raised amount of available iron, however special amount of proteins in the fosvitina/lipovitelina, comparing themselves with the cycles initial and intermediate. The iron availability more was raised in egg yolks that had passed for cooking process, however in hens of final position.
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Current Views on Creating Families: Adoption, Assisted Reproduction and Family Relationships

Weiss, Allison R January 2003 (has links)
Thesis advisor: Diane Scott-Jones / The purpose of this study was to explore young adults' views on building their future families; methods of having children including adoption, in vitro fertilization (IVF), donor insemination, egg donation, and surrogacy; disclosure of these methods to children; and the importance of children's contact with extended family. The sample consisted of 82 Boston College students, 41 males and 41 females, with a mean age of 20.67 years. Participants completed a questionnaire and an open-ended interview. The majority of the participants expected to have a life-long partner, raise at least one child, and help their children build relationships with extended relatives. Males and females did not differ on most questions; however females reported thinking about their future families more often than did males (p = .01), and females expected to start their families earlier than did males (p = .02). Participants were more open to adoption than to assisted reproduction technology (ART). IVF was the most preferred among the methods of ART (p < .001). Participants reported they would be most likely to disclose information to their child had they used adoption or ART and were the genetic parent. Some participants emphasized the importance of disclose to a child had they used ART and were not the genetic parents; approximately one-fourth of participants affirmed that a child has a right to know. Participants reported it would be easier to answer their children's questions about adoption or ART than to initiate a discussion on these topics with their children (p < .001). The majority of participants reported that it was important to help their children build connections with extended family and they planned to accomplish this through visiting and preserving family traditions. The findings provide insight into young adults' expectations for creating their families. / Thesis (BA) — Boston College, 2003. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Psychology. / Discipline: College Honors Program.

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