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The network of intertextual relations in Naipaul's half a life and magic seedsRohde, Larissa January 2005 (has links)
Esta dissertação mapeia a rede de relações intertextuais em Half a Life (2001) e sua continuação Magic Seeds (2004), os romances mais recentes do Prêmio Nobel de Literatura de 2001, V. S. Naipaul, como contribuição para o estudo da obra do autor. A noção de intertextualidade permeia os estudos literários, e o termo tem sido largamente empregado desde que foi cunhado por Julia Kristeva nos anos sessenta. Desde então as mais variadas, e muitas vezes divergentes, teorias sobre intertextualidade compartilham a idéia de que um texto só adquire significado pleno na interação com outros textos. A abordagem metodológica proposta é baseada na teoria da transtextualidade de Gérard Genette. Esta escolha implica o estudo de intertextos, paratextos, metatextos, arquitextos e hipertextos que constituem a interface entre os dois romances e outros escritos. O nome do protagonista "William Somerset Chandran" constitui o fio que guia o estudo das várias relações transtextuais nos dois romances. A partir do prenome do protagonista – William – este estudo situa os romances no contexto da tradição do Bildungsroman, e argumenta que estes estabelecem uma paródia arquitextual do gênero na medida em que subvertem seu cerne, ou seja, a formação do caráter do protagonista. O nome do meio do protagonista – Somerset – remete à ficcionalização do escritor Somerset Maugham na narrativa, ao mesmo tempo em que esta desmistifica a ótica ocidental sobre o hinduísmo popularizada por Maugham em The Razor's Edge. O sobrenome do protagonista – Chandran – leva ao estudo do conjunto de referências à origem indiana de Naipaul e o papel desta na produção do autor. Este nome se reporta ao romance de Narayan The Bachelor of Arts, cujo protagonista também é nomeado Chandran. Narayan é um escritor de destaque na literatura anglo-indiana e referência recorrente na obra de Naipaul. Os temas de migração e choque cultural apresentados nos dois romances têm sido presença constante na obra de Naipaul. Esta pesquisa mapeia a relação de continuidade entre os dois romances em questão e o conjunto da obra de Naipaul, salientando o papel da ambientação geográfica da narrativa, marcada pela jornada do protagonista através de três continentes. A teoria da transtextualidade é uma ferramenta operacional para a pesquisa, a qual examina a densidade das referências geográficas, históricas e literárias em Half a Life e Magic Seeds, visando aportar elementos para o estudo da produção literária de Naipaul, na medida em que estes romances recentes condensam e revisitam a visão de mundo deste autor. / This thesis traces the network of intertextual relations in the two latest novels by the 2001 Nobel Prize winner V. S. Naipaul: Half a Life (2001) and its sequel Magic Seeds (2004) as a means of contribution to the study of the author's work. The notion of intertextuality is a pervasive one within literary studies, the word itself started to be widely used in the sixties, following the definition of Julia Kristeva. Nuanced and even conflicting as the varied theories of intertextuality may be, they all share the idea that a text is not isolated or self-sufficient, but acquires full meaning in the interplay with other texts. A methodological approach based on Gerard Genette's theory of transtextuality is proposed for the analysis. This choice implies the study of intertexts, paratexts, metatexts, architexts and hypertexts that constitute the interface between the two novels at hand and other texts. The protagonist's name "William Somerset Chandran" sets the thread of several transtextual instances pervading the two novels. Taking the cue of the protagonist's first name – William – this thesis places the novels within the context of the Bildungsroman tradition and argues that these novels establish an architextual parody of this genre, subverting its core meaning of character formation. The protagonist's middle name – Somerset – leads to the discussion of the way the writer Somerset Maugham is fictionalized in the narrative and how it undermines the metropolitan ethos towards Hinduism as exposed in Maugham's novel The Razor's Edge. The protagonist's last name – Chandran – spawns a set of references to Naipaul's Indian ancestry and the role it plays in his fictional and non-fictional production; this name alludes to Narayan's novel The Bachelor of Arts, whose main character is also called Chandran. Narayan is a leading figure in Anglo-Indian Literature and a recurrent reference in Naipaul's writings. The themes of displacement and culture clash tackled by these novels have haunted the author throughout his career. The research maps out the two novels' relationship with the realm of Naipaul's previous writings; as well as brings to the fore the role of setting in the narratives, marked by the protagonist's dislocations in three continents. The theory of transtextuality provides the operational tool for the research, which examines the density of geographical, historical and literary references in Half a Life and Magic Seeds with the purpose of shedding light into Naipaul's literary production, inasmuch as these two recent novels condense and revisit the author's worldview.
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Método de estufa para determinação do grau de umidade de sementes de arroz e soja / The oven drying method for determination of the moisture content of rice and soybean seedsLopes, Madelon Schimmelpfennig 05 June 2008 (has links)
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Previous issue date: 2008-06-05 / The aim of this work was to a) compare the standard official methodology in Brazil for the determination of the moisture content of rice and soybean seeds (i.e. oven dried at 105°C for 24 hours) to the ISTA standard method (103°C for 17 hours), and b) test the possibility to determine whether the moisture content (MC) of rice and soybean seeds can be accurately estimated drying for a period shorter than 24h. Previously, a study was performed to establish the influence of the sample position within the oven, aimed to reduce the variation of the results on MC among different seed samples.
The rice and soybean seeds tested in the experiment showed MC as determined by oven drying at 105°C/24h of 9.0%; 17.6% and 7.5%; 16.8%, respectively. The MC of whole rice and soybean seeds was estimated through oven drying at temperatures of 70, 103, 105 e 130°C for periods of 1, 3, 5, 7, 17, 24, 48, 72 and 96 hours for each level of temperature. Following ISTA standards, ground seeds were employed to
determine their MC through the standard procedure (oven dried at 103°C/17h), whereas for the alternative procedure rice seeds were oven dried at 130°C for two hours. It was concluded that drying at 105°C/24h either underestimate the MC of rice and soybean seeds, when the MC was under 10% and overestimate when was equal or superior of 17,6%. It is possible to estimate its value in whole soybean seeds by
drying them at 130°C for less than 24h depending of the seeds MC. / O presente trabalho teve como objetivos: a) comparar o método oficial de determinação do grau de umidade de sementes de arroz e soja utilizados no Brasil (Estufa a 105°C/24 horas) com o método de referência Estufa a 103°C/17 horas, adotado pela ISTA, e b) verificar a possibilidade de determinação do grau de umidade das sementes de arroz e soja em tempo inferior a 24 horas. Estudo prévio foi realizado para verificar a influência da posição da amostra na estufa com a finalidade de reduzir a variação na determinação do grau de umidade das sementes analisadas. Foram utilizadas sementes de arroz e de soja, com graus de umidade obtidos pelo método de Estufa a 105°C/24 horas de 9,0%; 17,6% e 7,5%;16,8%, respectivamente. Foram determinados os graus de umidade das sementes inteiras
de arroz e soja, em estufa do tipo mecânico de ar forçado, submetidas às temperaturas de 70, 103, 105 e 130°C por um período de 1, 3, 5, 7, 17, 24, 48, 72 e 96 horas, para cada uma das temperaturas utilizadas. Foram utilizadas sementes
moídas, segundo critérios da ISTA, para a determinação do teor de água pelo método de referência (Estufa a 103°C/17 horas), e para a determinação do grau de umidade pelo método alternativo para sementes de arroz Estufa a 130°C por 2 horas. O método de Estufa a 105ºC/24h subestima o teor de água das sementes de arroz e soja com grau de umidade inferior a 10% e superestima o teor de água das sementes quando for igual ou superior a 17,6%. É possível determinar o teor de água das sementes de soja em tempo inferior a 24 horas, utilizando sementes inteiras e temperatura de 130ºC, dependendo do teor de água das sementes.
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Herança genética e potencial de armazenamento de sementes de híbridos de milho / Genetic inheritance and storage potential of corn hybrids seedsCapelaro, Ademir Luiz 28 March 2014 (has links)
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Previous issue date: 2014-03-28 / The present study aimed to evaluate the effects of genetic inheritance in the physiological quality and the storage potential of some corn hybrids seeds produced in the field and stored in two different environments: cold room and common
warehouse, for a period of eighteen months. To this study were produced seeds from six corn hybrids by crossing a group of three male parental lines with two female parental lines. Seeds from these hybrids were produced in the Syngenta Production Research field area, located at Tupaciguara-MG, under a high technology environment/condition with a necessary isolation in order to prevent any kind of
contamination between their parents. Harvest was done in spikes and after drying and processing, 10 kg of seeds samples each hybrid and parent lines corresponding to 20R size were separated. Then these samples were divided in two sub-samples of 5 kg each one and storage in two different environments: cold room at 10 º C and 60 % RH and common warehouse in natural enviroment (25 - 35° C and 30 - 90% RH). Seeds quality for the two environment conditions was evaluated by using the germination test, acelerating aging test (EVA) and cold test, for a period of eighteen months. The statistical design was completely randomized factorial 3x5 for each hybrid and male and female parent, in five evaluation periods, performed separately for each storage condition, with four replications in case of germination and three replications for each treatment in case of accelerated aging test and cold test. According the results was possible to conclude that the physiological quality of the seeds and their longevity (shelf life) was similar for all hybrids, independent of the different combination of their respective male and female. Also the hybrids have ever presented better performance of their respective parental lines. In all situations evaluated was observed that the hybrids presented higher performance to
physiological quality than their respective parent lines, indicating that the effects of the heterosis was very important. / O presente trabalho teve o objetivo de avaliar o efeito da herança genética na qualidade e no potencial de armazenamento de sementes de híbridos de milho, produzidas em condições de campo e armazenadas em dois ambientes diferentes: armazém climatizado e armazém convencional. Para tanto, foram produzidas sementes de seis híbridos simples de milho, através do cruzamento de um grupo de três linhagens parentais masculinas com duas linhagens parentais femininas. As sementes dos referidos híbridos foram produzidas no campo de Pesquisa de Produção da Syngenta Seeds, localizada no município de Tupaciguara/MG, em condições de alta tecnologia e com todos os isolamentos necessários para evitar qualquer tipo de contaminação entre os parentais. A colheita foi realizada em espigas que após a sua secagem e beneficiamento, originaram dez kg de sementes de cada um dos genótipos utilizados, híbridos e linhagens parentais, separadas em peneira 20R. Em seguida esta amostra foi dividida em duas sub-amostras de cinco kg, sendo cada uma delas armazenadas em dois diferentes ambientes: armazém
climatizado com 10 ºC e 60 % UR; armazém convencional em condições de ambiente natural (25 a 35° C e 30 a 90% UR). A qualidade das sementes, para as duas condições de armazenamento, foi avaliada pelo teste de germinação, teste de envelhecimento acelerado e teste de frio. O delineamento estatístico utilizado foi inteirarmente casualizado em esquema fatorial 3x5, para cada híbrido e parental masculino e feminino, em cinco épocas de avaliação, realizadas separadamente
para cada condição de armazenamento, com quatro repetições para cada tratamento no caso do teste de germinação e três repetições para cada tratamento nos testes de vigor envelhecimento acelerado e teste de frio. Quanto a significância, realizou-e análise de regressão polinimial. Concluiu-se que a qualidade e o potencial de armazenamento das sementes foram semelhantes para todos os híbridos,
independentemente da combinação entre os respectivos parentais masculinos e femininos. O comportamento de cada híbrido foi independente do parental masculino utilizado no cruzamento com cada um dos parentais femininos. Em todas as situações avaliadas observou-se que os híbridos apresentaram uma qualidade fisiológica bastante superior em relação aos seus respectivos parentais, masculinos
e femininos, indicando que houve um efeito da heterose na qualidade fisiológica das sementes.
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MECANISMOS DE REGENERAÇÃO NATURAL EM FLORESTA ESTACIONAL DECIDUAL, SANTA MARIA, RS / MECHANISMS OF NATURAL REGENERATION IN ESTACIONAL DECIDUAL FOREST, SANTA MARIA, RSSccoti, Marta Silvana Volpato 27 February 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study evaluated the mechanisms of natural regeneration represented by seeds rain, seeds bank of the soil and the regeneration vegetation, considering the
seedlings bank and the established regeneration, in a fragment of Estacional Decidual Forest. The evaluation was made with 70 randomized samplings in 14 parcels inside four bands, with systematic distribution in the area. The seeds rain was studied using 70 collectors with 1 m x 1 m, the collected material was analyzed monthly, during a year. In the seeds bank was collect 70 samplings using an iron collector (25 x 25 cm) on the soil surface and adjusting the studied samplings to 5 cm of deep. The collected material was taken to the Laboratory of Silvicultura of the Departament of Ciências Florestais of the Federal University of Santa Maria, where it
was evaluated during seven months. The seeds bank was evaluated in 70 sampling units of 2 x 2 m where was identified and measured all plants with h ≥ 30 cm and
DBH < 1 cm, the natural regeneration in the area was evaluated in 70 sampling units of 5 x 5 m, in which were identified and measured all plants with 1cm ≤ DBH ≤ 5 cm.
The regeneration mechanisms were analyzed in groups formed in the adult vegetation. In the seeds rain it was observed the presence of 73 species, mainly trees. The seeds bank of the soil show predominance of herbaceous species, and
some trees and bush-like species, pioneer species and secondary species. In the seedlings bank, was observed the presence of light demanding tree species and eciofiles species, while in the established natural regeneration the predominance was of shadow species. The seed bank of the soil and the established natural regeneration show different comportment for the group 1 and 2 in the adult
vegetation, while the seeds rain and seedlings bank show uniformity in the forest. The species with the bigger probability to perpetuate in the studied forest reminiscent
and in the near areas were Gymnanthes concolor, Soroceae bonplandii, Eugenia rostrifolia, Trichilia claussenii, Trichilia elegans, Myrocarpus frondosus, Cupania
vernalis, Nectandra megapotamica and Dasyphylum spinescens, these species can be used to enrichment and recuperation of the forest. The most restricted species
were Cordia tricotoma, Luehea divaricata, Sebastiania commersoniana and Syagrus rommanzoffiana, these species may grow in the forest if used the right treatments to
their perpetuation. The indicative species in the adult vegetation groups have the seeds rain and the seedlings bank as the main mechanisms for their conservation in
the forest reminiscent. / Este estudo avaliou os mecanismos de regeneração natural, representada pela chuva de sementes, banco de sementes do solo, e vegetação em regeneração, considerando banco de plântulas e regeneração natural estabelecida, em
remanescente de Floresta Estacional Decidual. A avaliação foi realizada em 70 subparcelas, aleatorizadas em 14 parcelas, dentro de 4 faixas distribuídas sistematicamente, na área. A chuva de sementes foi estudada em 70 coletores de 1
m x 1 m, cujo material era coletado mensalmente para avaliação, no curso de um ano. No banco de sementes do solo foram coletados 70 amostras, a partir de um gabarito de ferro (25 x 25 cm), que colocado sob a superfície do solo permitia a padronização da área para coleta em 5 cm de profundidade. O material coletado foi levado para o Laboratório de Silvicultura do Departamento de Ciência Florestais da Universidade Federal de Santa Maria, onde foi avaliado durante 7 meses. O banco de plântulas foi avaliado em 70 unidades amostrais de 2 x 2 m, onde identificaram-se e mediram-se todos os indivíduos com h ≥ 30 cm e DAP < 1 cm. A regeneração natural estabelecida foi avaliada em 70 unidades amostrais de 5 x 5 m. Nestas, identificaram-se e mediram-se todos os indivíduos com 1cm ≤ DAP < 5 cm. Os
mecanismos de regeneração foram analisados em agrupamentos, formados na vegetação adulta. Na chuva de sementes, observou-se a presença de 73 espécies, principalmente, arbóreas. O banco de sementes do solo teve predomínio de espécies herbáceas, além de arbóreas e arbustivas, espécies pioneiras e secundárias iniciais. No banco de plântulas observou-se a presença de espécies heliófilas e eciófilas, enquanto na regeneração natural estabelecida foi verificado o predomínio de espécies de sombra. O banco de sementes do solo e a regeneração natural estabelecida apresentaram comportamento diferente para o grupo 1 e 2 da vegetação adulta, enquanto a chuva de sementes e banco de plântulas apresentaram uniformidade na floresta. As espécies com maior potencialidade para perpetuar no remanescente de floresta estudado foram Gymnanthes concolor, Soroceae bonplandii, Eugenia rostrifolia, Trichilia claussenii, Trichilia elegans e Dasyphylum spinescens, sendo indicadas para enriquecimento. As espécies com maior restrição, foram Cordia tricotoma, Myrocarpus frondosus, Cupania vernalis, Nectandra megapotamica, Luehea divaricata, Sebastiania commersoniana e Syagrus rommanzoffiana, dependendo de tratamentos silviculturais na floresta para garantir sua perpetuação. As espécies indicadoras dos agrupamentos, na vegetação adulta, têm a chuva de sementes e banco de plântulas como principais mecanismos de conservação das espécies no remanescente.
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Fruiting strategies of the woody vine Parthenocissus quinquefoliaPacey, Carol. January 1985 (has links)
Call number: LD2668 .T4 1985 P32 / Master of Science
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A computational fluid dynamics study of the near surface wind patterns over a desert dune and the effect on seed dispersionJoubert, Eugene Christiaan 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2010. / ENGLISH ABSTRACT: This project originated when a team of scientists at the Gobabeb training and research and centre
observed seed accumulation sites on the slope of sand dunes in the Namib Desert. Seeds that
accumulate on the slip face of a sand dune provide food for small desert creatures that in turn
attract larger animals, resulting in a small ecosystem on the side of the dune. Since wind is the
primary transport of seeds throughout the Namib Desert it is of interest to investigate wind
patterns over the dune. In this project it is therefore desired to look at seed dynamics and
deposition as a result of near surface wind patterns around a three-dimensional dune geometry
using computational fluid dynamics. The project is a joint venture between the University of
Stellenbosch and the University of Namibia. This document presents the South African MScEng
thesis part.
The literature review shows the dominant winds in the Namib Desert to be from the south to
westerly direction. Previous studies on air flow over dunes focussed on sand movement and were
often limited to simplified two-dimensional geometries and steady state simulations. From these
studies the basic flow features associated with dunes can be identified. Lastly, factors that
influence particle dynamics around dune geometries are looked at. These particle studies mostly
involve the movement of sand rather than seeds but still provide valuable insight.
The project methodology is explained and includes the equipment used, the considerations taken
into account, the simplifications made as well as the procedure followed when conducting field
work and simulations. A section of an actual Namibian linear dune is mapped in order to obtain
a geometry for the simulations. Flow measurements are carried out with a wind mast to obtain
velocity profile inlet conditions for the simulations. Furthermore, seed sampling is done by the
collaborating Namibian team of which the data is used to obtain an effective seed particle model.
Lastly, simulations are carried out using primarily OpenFOAM-1.5. The simulations look at
general near surface wind patterns, time dependant flow features and particle movement and seed
deposition around and on the linear dune.
The results show different wind profiles for different wind direction. It is also possible to see
how the profile changes as the flow accelerates up the dune slope. Two-dimensional results
provide the opportunity to compare results with previous studies as well as to provide the basis
for looking at aspects such as differencing schemes, turbulence models and parallel computing
before three-dimensional simulations are carried out. The importance of higher order
differencing schemes are confirmed in the two-dimensional results. The turbulence models,
however, produce very similar results. The results from the two- and three-dimensional results
show typical flow features associated with dunes. Transient flow features and separation vortex
structures can be identified from time dependant simulations. Furthermore, particle simulations
reveal how particles tend to be trapped in the recirculation regions.
The conclusions explain how the project objectives were achieved and provide recommendations
for future studies related to this project. / AFRIKAANSE OPSOMMING: Die projek het ontstaan toe naforsers areas van saad akumulasie op die hellings van duine in
Namibë opgelet het. Hierdie akumulasie van plant materiaal verskaf die voedsel vir klein diere
op die duin wat ‘n klein ekosisteem tot gevolg het. Aaangesien die primêre vervoermiddel vir
sade in die woestyn wind is beoog die projek om deur die wind patrone oor die duin beter te
verstaan die saad verspreiding te beskryf. Die doel is dus om saad verspreiding en akumulasie te
beskryf deur die wind patrone te bekyk wat die verspreiding tot gevolg het deur gebruik te maak
van numeriese vloei dinamika. Die projek is ‘n saamgestelde projek tussen die Universiteit van
Stellenbosch en die Universiteit van Namibië. Hierdie dokument behels die Suid Afrikaanse
MScIng gedeelte van die projek.
Deur die hersiening van literatuur word daar gesien dat die domineerende wind rigtings as suid
tot wes beskryf kan word. Vorige studies wat verband hou met wind vloei oor duine wys dat die
meeste op twee-dimensionele eenvoudige geometrië gefokus het met tyd onafhankike simulasies.
Dit is egter moontlik om die resultate te gebruik om karakteristieke vloei patrone te identifiseer
wat met duin wind patrone geassosieer kan word. Laastens word daar gekyk na die faktore wat
partikel beweeging beïnvloed, maar hierdie studies sluit hoofsaaklik sand partikels in eerder as
sade.
Die motodologie beskryf die toerusting, oorwegings en prosedures wat gevolg is tydens veld
werk asook simulasies. Tydens die veld werk is ‘n gedeelte van ‘n Namib lineêre duin gemeet en
so gebruik om ‘n geometrie te maak wat vir simulasie doeleindes gebruik kan word. Daar is ook
wind meetings gedoen met ‘n wind mas om wind profiele vir inlaat kondisies vir die simulasies te
kry. Verder het saad bestudeering die nodige data verskaf om ‘n voledige saad partikel model op
te stel wat in die simulasies gebruik kan word. Laastens kyk die simulasies veral na algemene
vloei patrone, tyd afhanklike vloei effekte en ook partikel beweging in die vloei veld.
Die resultate wys hoe wind profiele verskil wat van verskillende rigtings af waai. Dit is ook
moontlik on te wys hoe die wind profiele verander soos die wind versnel teen die duin op. Tweedimensionele
simulasies verskaf die geleentheid om te kyk na die effek van verkillende
numeriese modelle, turbulensie modelle en ook multi-prosesseerder verwerking. Tydens die
twee-dimensionele simulasies is die belangrikheid van hoër orde numeriese metodes besef. Die
verkillende turbulensie modelle het egter klein verkille gewys. Alby die twee- en driedimensionele
resultate wys karakteristieke vloei patrone wat met duine geasosieer kan word.
Verder het tyd afhanklike simulasies gewys hoe wind patrone verander met tyd. Die partikel
simulasies wys ook die beweging van partikels deur die wind en hoe dit neig om te akumuleer in
die hersirkulasie gebied agter die duin.
Die gevolgtrekkings wys dat al die doelstellings bereik is en maak voorstelle vir toekomstige
studies wat met hierdie studie verband hou.
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The influence of processing of soyabeans and sunflower seed on their energy and amino acid availability for poultryDe Beer, Marc 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: 1. The effect of heat-treatment and dehulling of full-fat soya (Glycine
max) on AMEn' amino acid availability and broiler performance.
Heat treatment and dehulling of full-fat soya were evaluated in terms of their effect on
AMEn, apparent amino acid availability and broiler performance. Four products were
tested: raw whole soya (RWS), raw dehulled soya (RDS), extruded whole soya
(EWS) and extruded dehulled soya (EDS). Trials were conducted to determine AMEn
values and apparent amino acid availability of the products. A 42-day broiler trial was
conducted to measure the effect of extrusion and dehulling on broiler performance.
Test products were added to the diets at levels up to 263.2 g/kg in the starter diet and
260.0 g/kg in the finisher diet. Results indicated that extrusion cooking improved
AMEn and apparent amino acid availability. This was reflected in the improved
performance of broilers fed extruded soya as compared to raw soya. Increasing
amounts of RWS and RDS led to decreases in mass and intake and poor feed
conversion ratio (FeR) due to the presence of anti-nutritional factors. Broilers fed
EWS were heavier, consumed more feed and had better FeR than those fed RWS or
RDS. Dehulling improved AMEn (EWS: 13.75 MJ/kg vs EDS: 15.09 MJ/kg) and
rendered a product with slightly higher levels of total amino acids. Broiler
performance did not reflect this as there was no difference in mass, intake or FeR
between broilers fed increasing levels of EWS or EDS. Lysine and arginine were less
available in EDS than EWS indicating the possible over-cooking of EDS. Levels of
EWS and EDS of 263.2 g/kg in the starter and 260.0 g/kg in the finisher supported
maximum broiler performance.
2. The effect of heat-treatment and dehulling of full-fat sunflower
(Helianthus annuus) on AMEm amino acid availability and broiler
performance.
Heat treatment and dehulling of full-fat sunflower were evaluated in terms of their
effect on AMEn, apparent amino acid availability and broiler performance. Four
products were tested: raw whole sunflower (RWSF), raw dehulled sunflower (RDSF),
extruded whole sunflower (EWSF) and extruded dehulled sunflower (ED SF). Trials
were conducted to determine AMEn values and apparent amino acid availability of the
products. A 42-day broiler trial was conducted to measure the effect of expansion and
dehulling on broiler performance. Test products were added to the diets at levels up to
115.0 glkg in the starter diet and 181.5 glkg in the finisher diet. Dehulling rendered a
product with higher crude protein, ether extract, amino acid and AMEn values. AMEn
was only slightly improved by expansion. The AMEn values obtained were: RWSF:
16.03 MJ/kg, RDSF: 18.87 MJ/kg, EWSF: 16.22 MJ/kg, EDSF: 19.49 MJ/kg.
Dehulling had no effect on apparent amino acid availability. Expansion did not affect
apparent amino acid availability of dehulled full-fat sunflower but had a negative
influence on apparent amino acid availability of whole sunflower seeds. This
highlights the possible dangers of reduced protein quality as a result of overprocessing.
No differences were observed in terms of mass, intake and feed
conversion ratio of broilers fed any of the products during the 42-day broiler growth
trial. All products supported optimum broiler performance at levels up to 115.0 glkg
in the starter diet. For the finisher diets, optimum performance was maintained at
levels of 181.5 glkg, for RDSF and EDSF, while performance of broilers fed RWSF
and EWSF was optimal up to 145.2 glkg. / AFRIKAANSE OPSOMMING: 1. Die invloed van hitte-behandeling en ontdopping van
volvetsojabone (Glycine max) op SMEm skynbare aminosuur
beskikbaarheid en braaikuikenprestasie.
Hitte-behandeling en ontdopping van volvetsojabone is ge-evalueer in terme van hul
invloed op stikstof gekorrekteerde skynbare metaboliseerbare energie (SMEn)
waardes, skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Vier produkte
is getoets: rou heel sojabone (RWS), rou ontdopte sojabone (RDS), geekstrueerde
heel sojabone (EWS) en geekstrueerde ontdopte sojabone (EDS). Proewe is uitgevoer
om die SMEn waardes en skynbare aminosuur beskikbaarheid van die vier produkte te
bepaal. Gedurende 'n braaikuikengroeitoets van 42 dae is die invloed van hittebehandeling
(ekstrusie) en ontdopping op braaikuikenprestasie gemeet. Die vier
toetsprodukte is ingesluit in die aanvangsdieet teen peile van tot 263.2 g/kg en teen
peile van tot 260.0 g/kg in die afrondingsdieet. Resultate het getoon dat ekstrusie die
SMEn waardes en skynbare aminosuur beskikbaarheid verbeter het. Braaikuikens wat
geekstrueerde soja ontvang het, het beter gepresteer as braaikuikens wat rou soja
ontvang het. Verhoogte insluitings van RWS en RDS het gelei tot verlagings in massa
toename en voerinname en swak voeromsetverhoudings (VOV), as gevolg van die
teenwoordigheid van anti-voedings faktore. Braaikuikens wat EWS ontvang het, was
swaarder, het meer ingeneem en het beter vav gehad as die wat RWS of RDS
ontvang het. Ontdopping het SMEn verhoog (EWS: 13.75 MJ/kg vs EDS: 15.09
MJ/kg) en ontdopte produkte het klein hoeveelhede meer aminosure bevat. Dit het
egter nie in braaikuikenprestasie gewys nie. Daar was geen verskille in massa,
voerinname en vav tussen braaikuikens wat EWS of EDS ontvang het. Lisien en
arginien was minder beskikbaar in EDS as EWS wat op die moontlike oorprosessering
van EDS dui. Vlakke van EWS en EDS van 263.2 g/kg in die
aanvangsdieet en 260.0 g/kg In die afrondingsdieet het maksimale
braaikuikenprestasie ondersteun. 2. Die invloed
volvetsonneblosaad
van hitte-behandeling
(Helianthus annuus)
en ontdopping van
op SMEo, skynbare
aminosuur beskikbaarheid en braaikuikenprestasie.
Hitte-behandeling en ontdopping van volvetsonneblomsaad is geevalueer in terme van
hul invloed op stikstof gekorrekteerde skynbare metaboliseerbare energie (SMEn)
waardes, skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Vier produkte
is getoets: rou heel sonneblomsaad (RWS), rou ontdopte sonneblomsaad (RDS),
geekspandeerde heel sonneblomsaad (EWS) en geekspandeerde ontdopte
sonneblomsaad (EDS). Proewe is uitgevoer om die SMEn waardes en skynbare
aminosuur beskikbaarheid van die vier produkte te bepaal. Gedurende 'n
braaikuikengroeitoets van 42 dae is die invloed van hitte-behandeling (ekspansie) en
ontdopping op braaikuikenprestasie gemeet. Die vier toetsprodukte is ingesluit in die
aanvangsdieet teen peile van tot 115.0 g/kg en teen peile van tot 181.5 g/kg in die
afrondingsdieet. Ontdopte sonneblomsaad het hoer peile van ruproteien, eter-ekstrak
en aminosure as heel sonneblomsaad. SMEn waardes is ook hoer vir ontdopte
sonneblomsaad. Hitte-behandeling het SMEn waardes effens verhoog. Die bepaalde
SMEn waardes is as volg: RWSF: 16.03 MJ/kg, RDSF: 18.87 MJ/kg, EWSF: 16.22
MJ/kg, EDSF: 19.49 MJ/kg. Ontdopping het geen invloed op skynbare aminosuur
bekikbaarheid gehad nie. Skynbare aminosuur beskikbaarheid van ontdopte
sonneblomsaad IS me deur hitte-behandeling beinvloed nie, terwyl die van heel
sonneblomsaad negatief beinvloed is. Dit beklemtoon die gevare van verswakte
proteien kwaliteit as gevolg van oor-prosessering. Geen verskille is opgemerk in
terme van massa, voerinname en voeromset verhouding (VOV) tussen die vier
produkte gedurende die braaikuikengroeitoets van 42 dae. Alle produkte het
maksimale braaikuiken prestasie ondersteun in die aanvangsdieet teen vlakke van
115.0 g/kg. In die afrondingsdieet het RDSF en EDSF optimale braaikuikenprestasie
onderhou teen vlakke van 181.5 g/kg, terwyl RWSF en EWSF net t
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Analysis of vegetable oils, seeds and beans by TGA and NMR spectroscopyRetief, Liezel 03 1900 (has links)
Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Due to the commercial, nutritional and health value of vegetable oils, seeds and beans, the
analysis of their components is of much interest. In this dissertation oil-containing food
products, specifically vegetable oils, seeds and beans, were investigated.
Selected minor components of three locally produced vegetable oils, namely apricot
kernel, avocado pear and macadamia nut oils were investigated using 31P NMR
spectroscopy. These minor components, including 1,2 diacylglycerols, 1,3 diacylglycerols
and free fatty acids, were identified in the 31P NMR spectra of each of the three vegetable
oils for the first time. Two approaches were used for the quantification of the minor
components present in the spectra. A calibration curve approach used known
concentrations of standard minor components to establish calibration curves while a direct
correlation approach calculated the unknown concentration of minor components in the
vegetable oils using a known amount of standard compound within the analysis solution.
These approaches aided in determining the concentration of minor components during
storage studies in which vegetable oils were stored in five different ways: exposed to light,
in a cupboard, in a cupboard wrapped in tin foil, at -8 °C and at 5 °C. It was found that
determining the best storage condition for each oil was difficult since individual minor
components were affected differently by the various storage conditions. However, in
general the best storage conditions appeared to be 5 °C and -8 °C.
The oil, protein and carbohydrate contents of sesame, sunflower, poppy, and pumpkin
seeds, and soy, mung, black and kidney beans were analysed by thermogravimetric
analysis and 13C NMR solid state NMR spectroscopy. It was shown that the first derivative
of TGA data for seeds and beans can give valuable information about the carbohydrate,
moisture, protein and fat content. This has not been previously demonstrated. For the
seeds, the integration of a region between 270–480 ºC was equal to the sum of the oil and
protein content and compared well to quantitative results obtained by other conventional
methods. For beans the integration of a region between 180-590 ºC, gave a value which
represented the sum of the oil, protein and carbohydrate content.
13C solid state NMR spectroscopy, including SPE-MAS, CP-MAS and variable contact time
experiments, was carried out on these seeds and beans and gave valuable information on
the solid-like and liquid-like components. To our knowledge these seeds and beans have
never been previously analysed using this technique. 13C SPE-MAS NMR spectroscopy
indicated that the seeds contained more liquid-like components than the beans. In turn the
13C CP-MAS NMR spectra indicated that beans had higher levels of solid-like components
than the seeds. These conclusions correlated well with the quantities of liquid-like
components and solid-like components that were determined by conventional methods
and TGA. Preliminary studies using T1pH experiments on the components present in the
seeds and beans led to a few observations. Most interesting is that a model using a two-
phase fit in order to determine T1pH values appears to be more accurate than a one-phase
model. / AFRIKAANSE OPSOMMING: Groente olies, sade en bone is ‘n onderwerp van groot belang omrede hul kommersiële,
voeding en gesondheidswaardes. In hierdie tesis is olie-bevattende voedselprodukte,
spesifiek groente-olies, sade en bone geanaliseer.
Geselekteerde komponente teenwoordig in klein hoeveelhede in drie lokaal
geproduseerde groente-olies, naamlik appelkoos-pit, avokadopeer en makadamia-neut
olies is geanaliseer met behulp van 31P KMR spektroskopie. Hierdie komponente,
insluitend 1,2 diasielglyserole, 1,3 diasielglyserole en ongebonde vetsure, is vir die eerste
keer geïdentifiseer in die 31P KMR spektra van die drie groente olies. Twee benaderings is
gebruik vir die hoeveelheids-bepaling van die komponente in die spektra. ‘n Yking-kurwe
metode het gebruik gemaak van bekende hoeveelhede konsentrasies standaard
komponente vir die opstel van yking-kurwes, terwyl ‘n direkte korrelasie metode gebruik is
om die onbekende konsentrasie van komponente in groente olies te bepaal met behulp
van ‘n bekende hoeveelheid standaard verbinding teenwoordig in die oplossing. Hierdie
metodes het gelei tot die bepaling van die konsentrasies van die komponente gedurende
vyf verskillende berging toestande wat ingesluit het: Blootgestel aan lig, in ‘n donker kas,
in ‘n donker kas toegevou in tin foelie, bevries by -8 °C en in ’n koelkas by 5 °C. Dit was
bevind dat bepaling van die beste bergingstoestand vir elke olie moeilik is aangesien die
individuele komponente verskillend geaffekteer word deur die verskeie berging toestande.
Die beste bergings toestand oor die algemeen blyk egter om by 5 °C en -8 °C te wees.
Sesamsaad, sonneblomsaad, papawersaad en pampoensaad sowel as sojaboontjie,
mungboontjie, swartboontjie en pronkboontjie se olie, protein en koolhidraat komponente
was geanaliseer met behulp van termogravimetriese analise (TGA) en 13C soliede
toestand KMR spektroskopie. Dit was bevind dat die eerste afgeleide van die TGA data
waardevolle inligting lewer oor die komponent inhoud van elk van die sade en bone.
Hierdie is nog nie vantevore bevind nie. Vir die sade, was die integrasie van ‘n area tussen
270–480 ºC gelyk aan die som van die olie en proteïen inhoud en het goed vergelyk met
die waardes verky deur algemene analitiese metodes. Vir die boontjies, was die integrasie
van ‘n area tussen 180-590 ºC gelyk aan die som van die olie, protein en koolhidraat
inhoud.
13C vaste staat KMR spektroskopie, insluitende SPE-MAS, CP-MAS en variëerbare
kontak-tyd eksperimente, was gedoen en het waardevolle inligting gelewer omtrent die
solied-agtige en mobiel-agtige komponente. Hierdie sade en bone is tot ons kennis nog
nie van te vore met die tegnieke ondersoek nie. 13C SPE-MAS NMR spektroskopie het
aangedui dat daar ‘n groter hoeveelheid mobiel-agtige komponente in sade as in bone
teenwoordig is. 13C CP-MAS NMR spektroskopie het weer aangedui dat daar ‘n groter
hoeveelheid solied-agtige komponente in bone as in sade teenwoordig is. Hierdie
gevolgtrekkings het goed vergelyk met die waarnemings verkry deur konvensionele
analitiese metodes en TGA. Voorlopige studies op die komponente van sade en bone deur
T1pH eksperimente het tot ‘n paar gevolgtrekkings gelei waarvan die mees interessantste
was dat ‘n twee-fase model vir die bepaling van T1pH waardes beter resultate lewer as ‘n
een-fase model.
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Synthesis and characterization of silicon nanowires, silicon nanorods, and magnetic nanocrystalsHeitsch, Andrew Theron 05 October 2010 (has links)
Silicon nanowires, silicon nanorods, and magnetic nanocrystals have shown interesting size, shape, mechanical, electronic, and/or magnetic properties and many have proposed their use in exciting applications. However, before these materials can be applied, it is critical to fully understand their properties and how to synthesize them economically and reproducibly. Silicon nanowires were synthesized in high boiling point ambient pressure solvents using gold and bismuth nanocrystals seeds and trisilane as the silicon precursor. Reactions temperatures as low as 410°C were used to promote the solution-liquid-solid (SLS) growth of silicon nanowires. The silicon nanowires synthesis was optimized to produce 5 mg of silicon nanowires with average diameters of 30 nm and lengths exceeding 2 [mu]m by adjusting the silicon to gold ratio in the injection mixture and reaction temperature. Silicon nanorods were synthesized using a solution-based arrested-SLS growth approach where gold seeds, trisilane, and a dodecylamine were vital to the success. Dodecylamine was found to prevent gold seed coalescence at high temperatures -- creating small diameter rods -- and bond to the crystalline silicon surface -- preventing silicon nanorod aggregation. Furthermore, an etching strategy was developed using an emulsion of aqua regia and chloroform to remove the gold seeds from the silicon nanorods tip. A thin silicon shell surrounding the gold seed of the silicon nanorod was subsequently observed. Multifunctional colloidal core-shell nanoparticles of iron platinum or iron oxide encapsulated in fluorescent dye doped silica shells were also synthesized. The as-prepared magnetic nanocrystals are initially hydrophobic and were coated with a uniform silica shell using a microemulsion approach. These colloidal heterostructures have the potential to be used as dual-purpose tags, exhibiting a fluorescent signal that could be combined with enhanced magnetic resonance imaging contrast. Compositionally-ordered, single domain, antiferromagnetic L1₂ FePt₃ and ferromagnetic L1₀ FePt nanocrystals were synthesized by coating colloidally-grown Pt-rich or stoichiometricly equal Fe-Pt nanocrystals with thermally-stable SiO₂ and annealing at high temperature. Without the silica coating, the nanocrystals transform predominately into the L1₀ FePt phase due to interparticle diffusion of Fe and Pt atoms. Magnetization measurements of the L1₂ FePt₃ nanocrystals revealed two antiferromagnetic transitions near the bulk Neél temperatures of 100K and 160K. Combining L1₂ FePt₃ nanocrystals with L1₀ FePt nanocrystals was found to produce a constriction in field-dependent magnetization loops that has previously been observed near zero applied field in ensemble measurements of single domain silica-coated L1₀ FePt nanocrystals. Dipole interactions between FePt@SiO₂ nanoparticles with varying SiO₂ shell thickness was also explored. / text
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Consequences of dispersal failure: kereru and large seeds in New ZealandWotton, Debra Mary January 2007 (has links)
The decline of kereru (Hemiphaga novaeseelandiae) may limit dispersal of large-seeded plants in New Zealand, but the consequences of this are unknown. I determined kereru disperser effectiveness by modelling seed dispersal distances (using seed retention times and movement patterns). Mean seed retention time was significantly longer for larger-seeded species, ranging from 37-181 minutes. Wild radiotracked kereru were sedentary, remaining at one location for up to 5.25 hours. The mean flight distance was 77 m and the maximum was 1, 457 m. Estimated mean seed dispersal distances for tawa (Beilschmiedia tawa), puriri (Vitex lucens), and fivefinger (Pseudopanax arboreus) were 95, 98, and 61 m respectively. Kereru dispersed 66-87% of ingested seeds away from the parent tree, with 79-88% of seeds dispersed <100 m and < 1% dispersed over 1,000 m. In a field seed-fate experiment, "pre-human" conditions (cleaned seeds, low density, away from parent, and protected from mammals) increased survival compared to "post-human" conditions (whole fruits, high density, under parent, not protected) for both taraire (Beilschmiedia tarairi; 15% vs. 2% survival to one year respectively) and karaka (Corynocarpus laevigatus; 60% vs. 11% to two years, respectively). Fruit diameter varied considerably within karaka, taraire, and tawa, although theoretically not enough for them to be swallowed by other birds. Nevertheless, other birds are reported to occasionally take fruits of nearly all large-seeded species. Small tawa seeds produced smaller seedlings in the glasshouse; therefore selection of only smaller seeds by alternative dispersers may negatively affect tawa recruitment. Kereru are generally not gape-limited, and fruit size preferences were independent of mean fruit size. Kereru provide effective dispersal by moving most seeds away from the parent, and enhancing seed and seedling survival. Therefore, both dispersal failure and introduced mammals negatively affect the regeneration of large-seeded trees in New Zealand.
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