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As political tensions spread across 1930s Europe, photographers and lovers, Endre Friedmann and Gerda Taro, create the persona of American photojournalist Robert Capa to conceal their Jewish identities. Under the guise of Capa, they put their lives on the front line to expose the humanitarian horrors of the Spanish Civil War with a name that will go down in history.

The Amadumbe crop [Colocasia esculenta (L.) Schott] is a traditional Southern African tuber crop which is rich in starch, mucilage and micronutrients. Amadumbe tubers have limited amount of proteins and as a result, amadumbe-processed foods lack adequate protein. The purpose of this study was therefore to develop protein-rich amadumbe-soya composite biscuits, which would be acceptable to consumers. Biscuits were prepared by combining amadumbe and soya flours at ratios: 90:10, 70:30 and 50:50. Functional properties of composite flours and the physical properties of composite biscuits were determined. The proximate composition, amino acid composition and protein digestibility of composite biscuits were determined. Consumer acceptability test of biscuits was performed using nine-point hedonic scale. The results indicated that the 90% amadumbe and 10% soya composite biscuits had high significant values of moisture, ash, carbohydrates contents and energy values. The 50% amadumbe and 50% soya composite biscuits had significantly high values of fat, crude protein contents and acid detergent fibre (ADF). The protein digestibility, amino acid contents, especially the lysine contents of composite biscuits increased significantly (p ≤ 0.05) with an increase in the percentage of soya. The mineral contents of composite biscuits; Ca, Mg, P, Zn, Cu, Mn and Fe increased significantly (p ≤ 0.05) with the increase of soya in the composite biscuits. There was a significant difference in the mean taste acceptability and mean overall acceptability when the soya concentration was increased to 50%. Soya was successfully used to produce amadumbe composite biscuits with better nutritional quality with respect to protein content, amino acid profile and selected mineral contents and which were acceptable to consumers. / National Research Foundation (South Africa) / Life and Consumer Science / M.Sc. (Agriculture)

Made available in DSpace on 2015-03-26T13:39:31Z (GMT). No. of bitstreams: 1 texto completo.pdf: 778433 bytes, checksum: 48b056351b5e2cda50984272cdf2967c (MD5) Previous issue date: 2009-02-10 / This study was carried out to evaluate the viability of the forced prerooting technique of some types of taro seedlings 'Japanese' in order to anticipate the harvest. The experiment was carried out in the research orchard pertaining to the Department of Plant Sciences, Universidade Federal de Viçosa, during the period from 07/07/2007 to 01/06/2008. It consisted of eight treatments represented by the following seedling types: 1 - Control (Rhizome- big sprout weighing 150g without prerooting); 2 - Rhizome-giant sprout (FGG with 300g); 3 - Rhizome-big sprout (FG with 150g); 4 Rhizome-medium sprout (FM with 70g); 5 Rhizome-small sprout (FP with 30g); 6 - Rhizome- refuse sprout (REF with 15g); 7 - Rhizomefemale parent with apical cut (RMãeap with 400g); and 8 - Rhizome- female parent with longitudinal cut (RMãelong with 400g). The control seedlings remained in the shed), whereas the seedlings of the treatments 2 to 8 were subjected to forced prerooting for 60 days, in the nursery provided with bed constituted by layer of cattle raw manure + pricked napier grass and covered with topsoil + sand layer (2:1,v:v). The nursery covering was made under low-tunnel form, by using a 150μm plastic film, in order to maintain the higher temperature and to stimulating the rooting of the seedlings. After 60 days, the seedlings were planted at spacing 1.0 x 0.30m in the field. The randomized block design was used, with four replicates. Two harvests were accomplished in the field: the first one at 210 and the 2nd at 270 days after planting. Both growth and yield characteristics were evaluated. The data were subjected to variance analysis and the averages were compared to the averages of the control by the Dunnett test at 10% probability. The prerooting made possible to reduce the permanence time of the crop in the field. The treatments 6 and 8 showed the worst performance concerning to commercial production at both harvesting times. Concerning to commercial production, the treatment 2 was distinguished from the other treatments; however, it requires high amount of propagative material. The seedling types of the treatments 5 and 7 provided high productivity, therefore they could reduce the cost/benefit relationship due to the lower expense of the propagative material. According to the results, it is concluded that the forced prerooting is viable, when aiming at reduction of the permanence time of the crop in the field. / O trabalho objetivou avaliar a viabilidade da técnica do préenraizamento forçado de tipos de mudas de taro Japonês visando à antecipação da colheita. O experimento foi conduzido na Horta de Pesquisas do Departamento de Fitotecnia da Universidade Federal de Viçosa, no período de 07/07/2007 a 01/06/2008. O experimento consistiu de oito tratamentos, representados pelos tipos de muda: 1- Controle (Rizoma-filho grande com 150 g, sem pré-enraizamento); 2- Rizoma-filho gigante (FGG com 300 g); 3- Rizoma-filho grande (FG com 150 g); 4- Rizoma-filho médio (FM com 70 g); 5- Rizoma-filho pequeno (FP com 30 g); 6- Rizoma-filho refugo (REF com 15 g); 7- Rizoma-mãe com corte apical (RMãeap com 400 g) e 8- Rizoma-mãe com corte longitudinal (RMãelong com 400 g). As mudas do controle permaneceram no galpão, as mudas dos tratamentos 2 a 8 foram submetidas ao pré-enraizamento forçado, por 60 dias, em viveiro com leito constituído por camada de esterco bovino crú + capim napier picado, coberto com camada de terriço + areia (2:1,v:v). O viveiro foi coberto com filme de plástico de 150 μm, tipo túnel baixo, para manter a temperatura mais elevada e estimular o enraizamento das mudas. Após 60 dias, procedeu-se o plantio das mudas no campo em 05/09/2007, no espaçamento de 1,0 x 0,30 m. O delineamento experimental foi de blocos ao acaso, com quatro repetições. Procederam-se duas colheitas; a 1ª aos 210 e a 2ª aos 270 dias após o plantio no campo. Foram avaliadas características de crescimento e produção. Os dados foram submetidos á analise de variância e as médias comparadas às médias do controle pelo teste de Dunnett a 10% de probabilidade. O pré-enraizamento possibilitou a redução do tempo de permanência da cultura no campo. Os tratamentos 6 e 8 apresentaram o pior desempenho na produção comercial, em ambas épocas de colheita. O tratamento 2 destacou-se dos demais tratamentos quanto à produção comercial, todavia implica na necessidade de grande quantidade de material propagativo. Os tipos de mudas dos tratamentos 5 e 7, proporcionaram alta produtividade e poderiam reduzir a relação custo/benefício decorrente do menor gasto de material propagativo. Os resultados obtidos permitem concluir que o pré-enraizamento forçado é viável visando à redução do tempo de permanência da cultura no campo.

Le problème dans cette étude est celui de l’incorporation de la gomme Grewia mollis dans le mélange blé-taro avec pour objet d’améliorer le taux de substitution du blé par la farine de taro qui, selon la littérature, ne peut dépasser de valeurs allant de 10 à 15 % sans altérer de façon considérable la qualité de la pâte de pain. Les objectifs définis dans cette étude sont triples : (1) d’abord connaitre les propriétés de la farine de taro variété Lamba qui, avant cette étude n’a pas fait l’objet d’études antérieures. (2) Déterminer les conditions optimales d’extraction de la gomme Grewia, dont on connait de la littérature les caractéristiques physicochimiques et fonctionnelles et pas les meilleures conditions d’extraction. (3) Etudier dans un plan de mélange à trois composantes l’effet du pourcentage de gomme, de farine de taro et blé sur les propriétés rhéologiques et sensorielles de la pâte et du pain. Dans cette étude les méthodes usuelles de caractérisation ont été utilisées. Pour l’objectif 1, le dispositif expérimental prend en compte la taille du tubercule (4 modalités) comme facteurs, et les paramètres mesurés sont : la composition proximale, la granulométrie et la forme de particules, les propriétés thermiques et rhéologiques de la farine. Pour l’objectif 2, la gomme est extraite selon un plan composite centré à faces centrées avec comme facteurs le ratio volume d’eau sur masse de la poudre de l’écorce, la température et le temps d’extraction, et les réponses sont la viscosité de la solution et le taux d’extraction. Une caractérisation du profil de sucres de la gomme a été faite. Pour l’objectif 3, un plan de mélange ternaire Grewia-taro-blé à contraintes a été effectué. Le volume de pousse de la pâte, le test de double morsure, le test du fluage-recouvrement ont été mesurés sur la pâte, alors que les pains obtenus ont fait l’objet d’une analyse du test de double compression et d’acceptabilité. Les résultats de l’objectif 1 ont montré que la composition physicochimique du taro varie en fonction de la masse et du pelage, le profil en acide aminé présente une absence des acides aminés soufrés. Les résultats de l’extraction de la gomme dans l’objectif 2 ont montré que seul le ratio augmente significativement la viscosité et le rendement d’extraction de la gomme. Les conditions optimales d’extraction de la gomme Grewia mollis sont les suivantes: pH: 7,1 temps : 1h température: 73,1 °C ratio eau / poudre : 55,4 / 1, pour une viscosité de 0,98 Pa.s et un rendement de 0,32%. Les résultats de l’objectif 3 montrent que l’augmentation de la gomme Grewia mollis entraine une augmentation de la capacité d’absorption d’eau des farines mélangées, une augmentation de la viscoélasticité, du volume de pousse, du volume de pain, de l’acceptabilité générale jusqu’à un seuil de 2,5% puis une baisse est observée. Les analyses de corrélation ont montré que l’augmentation de la capacité d’absorption d’eau entraine une baisse des paramètres du fluage et du recouvrement de la pâte, du volume de pousse / The problem in this study is the incorporation of Grewia gum in the wheat-taro mixture in order to improve the level of substitution of wheat flour by taro flour which, according to the literature, cannot exceed 10-15% without deteriorating in a considerable manner the quality of the bread paste. The objective defined in this study is threefold : (1) to know the properties of the flour of taro Lamba variety which, before this study have not been the object for research (2) to determine the optimum conditions for extraction of the Grewia gum, with known physico-chemical and functional characteristics but no standard for conditions extraction. (3) To study the effect of the percentage of gum, taro flour and wheat flour on the rheological and sensory properties of the paste and the bread using a mixture designs with three components. In this study the usual methods of characterization were used. For objective 1, the experimental device takes into account sizes of tuber (4 weight) like factors, and the measured parameters are: the proximate composition, the granulometry and the shape of particles, thermal and rheological properties of the flour. For objective 2, the gum is extracted using a central composite design with faces centered with factors like the flour water ratio (w / w), the temperature, extraction time and pH, the response were the viscosity of the solution and the yield of extraction. A characterization of the sugar profile of gum was made. For objective 3, a ternary mixture design Grewia - taro-wheat with constraints was carried out. The volume of dough, the rheology of paste, the double bite test, the creep-recovering test were measured on the dough, whereas a double compression test analysis and acceptability were carried out on the bread. The results of objective 1 showed that the physico-chemical composition of the taro varies as a function of the mass and peeling type, the amino acid profile reveals the absence of sulphur amino acids. The results of the extraction of gum showed that only the ratio significantly increases the viscosity and the yield of the gum.The optimum conditions for extraction of the Grewia gum are as follows:pH: 7.1 times : 1h temperature: 73 °C water / powder ratio: 55.4 / 1, for a viscosity of 0.98 Pa.s and and yield of 0.32 %. The results of objective 3 show that the incorporation of gum increase the water absorption capacity, viscoelasticity of the dough, volume of the dough and even volume of bread. However the sensory analysis showed that the addition of gum up to 5% contributed to the rejection of the breads

Les résultats montrent que la teneur en cendres, protéines brutes, sucres disponibles, oxalates totaux, amidons et phosphore augmente significativement (p<0,05) avec la maturité. En revanche la teneur en amylose baisse avec la maturité. La capacité d'absorption d'eau, l'indice de solubilité, la température et l'enthalpie de gélatinisation (delta H) des farines et amidons augmentent significativement (p<0,05) en fonction du degré de maturité. Quel que soit le degré de maturité, les granules d'amidon ont présenté un diffractogramme caractéristique de type "A". Les précurseurs de brunissement augmentent significativement (p<0,05) avec le degré de maturité. Le paramètre L* des farines et des pâtes augmente alors que a* diminue en fonction du degré de maturité. Le paramètre L* est plus élevé et a* moins élevé dans le cas du séchage électrique que le séchage solaire. Les caractéristiques sensorielles des pâtes de taro Sosso sont affectées positivement par le degré de maturité et le séchage électrique. L'acceptabilité générale des pâtes de taro Sosso est corrélée à la couleur de celles-ci. Cette étude suggère que 10 mois de maturité de taro Sosso et le séchage électrique (40°C) sont des conditions favorables à l'obtention des pâtes de qualité acceptable / Results showed that the ash content, crude proteins, available sugars, total oxalate, starch and phosphorus content increased significantly with the maturity stage. On the other hand the amylose content decreased as function of the maturity. The water adsorption capacity, the water solubility index, the temperature and the enthalpy of gelatinization of the flour and starch increased significantly with the maturity stage. Irrespective of the degree of maturity the starch granules diffractogramm were exhibited an "A" type cristallinity. The browning indicators increased significantly (p<0.05) with the maturity stage of the tuber. The color coordinate L* of the flours and that of its dough increased while a* decreased with the maturity stage. These two coordinates lend themselves better with electric drying than solar drying. The sensory characteristics of the taro Sosso dough were positively affected by the maturity stage and electric drying. The overall acceptability of taro Sosso dough was correlated with its color. These results suggest that 10 months of the taro Sosso maturity and the electric drying (40°C) are the best conditions to obtain the acceptable pastes. These optimum conditions might be used to produce the taro flour at industrial scale

A Guerra Civil Espanhola (1936-1939) foi o primeiro conflito do século XX sistematicamente fotografado, essas imagens produzidas por diversos fotógrafos foram divulgadas através de revistas ilustradas. Essa pesquisa teve como objetivo analisar a fotografia como documento a partir das imagens de Robert Capa e Gerda Taro durante o conflito espanhol e publicadas nas revistas ilustradas Vu, Life e Picture Post e no livro Death in the making, buscando trabalhar as imagens pelos seus aspectos formais, comparando as formas de veiculação e produção de narrativas nas revistas ilustradas produzidas pelos editores e pelos fotógrafos no livro. Por fim, essa comparação busca refletir sobre as fotografias como formas de expressar a experiência da guerra e sobre que tipo de narrativa elas produzem. / The Spanish Civil War (1936-1939) was the first conflict of the twentieth century systematically photographed, these images produced by several photographers were disseminated through illustrated magazines. This research aimed to analyze photography as a document starting for the images produced by Robert Capa and Gerda Taro during the Spanish conflict and published in the illustrated magazines Vu, Life and Picture Post and in the book Death in the making, seeking to work the images by their formal aspects. And comparing their ways to convey and produce of narratives in the illustrated magazines produced by publishers or photographers in the book. Finally, this comparison seeks to reflect on the photographs as ways of expressing the experience of war and on what kind of narrative they produce.

Ethno-archaeological evidence shows that taro [Colocasia esculenta (L.) Schott] originated in Asia. It may have been brought into South Africa a few hundred years after 300 BC from Madagascar, where Malaysian settlers introduced it about 300 BC. The crop is grown in the tropical and subtropical regions of the world, largely for subsistence on farms. In South Africa, taro is mainly produced in the subtropical coastal belt, stretching from Bizana in the Eastern Cape to the KwaZulu-Natal north coast. Although it is a staple crop for the subsistence farmers who grow it, there are no data on taro agronomy in South Africa. The hypothesis of this study was that traditional knowledge about taro production practices is not adequate to form a basis for agronomic and extension interventions to promote the status of the crop to that of a commercial commodity. A survey was conducted at two districts in KwaZulu-Natal, Umbumbulu and Ndwedwe, where taro is a staple crop. The objective of the survey was to determine the cultural practices associated with taro production, including knowledge about varieties, agronomy, plant protection, storage and marketing. Qualitative data obtained from the survey was used to plan an investigation into the agronomy of taro. The survey showed that subsistence farmers at Ndwedwe and Umbumbulu used traditional methods for taro production that had very small influence from the extension services from the Department of Agriculture. The farmers identified three varieties of taro, which they designated as the "red", "white" and "Zulu" types. The "red" and "white" designations were based on consistent crop morphological characteristics. This finding confirmed the reliability of indigenous knowledge for crop classification.The survey also revealed that wetland and dryland conditions are used to produce taro. At Umbumbulu, production occurred predominantly under dryland conditions, whereas at Ndwedwe there was an almost even utilisation of both wetlands and drylands. At both locations, the farmers estimated plant spacing using their feet, which showed that the plant populations would be about 18400 plants ha(-1). Full corms were a predominant type of propagation material. In the light of the survey findings about site types (wetland or dryland), propagation material and plant spacing for taro production, field experiments were designed to 1) determine the effect of site type on taro production, 2) compare three propagule types (full corm, full corm with a shoot and half corm) in taro production and 3) examine the effect of planting density (18400, 24600 and 37000 plants ha(-1) on the performance of propagules with respect to production under wetland and dryland conditions. Field experiments showed that wetland cultivation improved taro yield by 40% compared with dryland production. However, in each of the two site categories, there were significant differences between sites. Using full corms with shoots also enhanced taro yield (42% > full corms without shoots and 66% > half corms), when means were determined across all sites and planting densities. Increasing planting density also caused an increase in taro production (4.9 t ha (-1), 6.8 t ha (-1) and 11.5 t ha (-1), for 18400,24600 and 37000 plants ha,(-1), respectively; LSD (0.05) = 1.4 t ha,1). The enhanced performance of taro under wetland conditions, where corms with a shoot were used and at high planting densities may have been associated with photosynthetic efficiency. Wetland conditions and corms with shoots improved plant emergence and plant growth, which are essential agronomic conditions for efficient capture of the sun's energy for photosynthesis. It is proposed that using propagules with shoots and high plant populations under dryland conditions could enhance taro production. Although wetland cultivation enhanced yield, the survey showed that the total area of land that could be used for wetland cultivation at Ndwedwe and Umbumbulu was too small to warrant sustainable wetland production. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

The presence of exotic plants both in Africa and in Asia has long attracted the attention of scholars who have attempted to understand the human activities linked to them. Archaeological and ethnographic evidence for the reconstruction of these activities is often very limited, but indirect methods such as the study of DNA have become useful tools in building models of early human dispersal. Among the plants that were carried across the Indian Ocean, sometimes known as the “tropical food kit”, the staple crop taro (Colocasia esculenta (L.) Schott) has continued to be the subject of ongoing research. The use of this crop in antiquity is well documented by discoveries of ancient taro starch granules found on archaeological artefacts from sites in Southeast Asia and the Pacific islands, making it one of the oldest plants consumed by people. However, less is known about the use of taro in Africa and the Mediterranean region, where it is found both in the wild and under cultivation - often representing a staple crop in Sub-Saharan Africa. In this doctoral thesis, genetic analysis was performed on modern samples of taro collected from Africa and other regions of the Indian Ocean, using four molecular markers. Two main clusters have been identified, and within this main sub-division four populations of taro have been detected in Africa. By integrating the genetic results with historical and linguistic research, and extensive ethnobotanical fieldwork in Africa, two of these populations are proposed to represent early translocations, with modern distribution patterns suggesting diverse dispersal routes at different times. These results open up a new scenario in which the “tropical food kit” is finally unpacked, with important historical implications for each of the crops contained within it.