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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.
71

A victimological study among Coloureds in the Cape Peninsula

Strijdom, Hendrik Gert January 1983 (has links)
From Introduction: Criminology developed as a reaction to the various revolutions that were occurring in the European countries during the eighteenth and nineteenth centuries. In response to the turmoil and disorder of Western society criminologists attempted to discover the natural laws of society hoping to establish a stable social order. Crime was regarded as something that disturbed society and, therefore, had to be controlled or prevented. According to Quinney and Wildeman (1977) the development of criminology can be viewed as an ongoing attempt to explain crime in terms of established social order. They state that in the history of criminology there is, however, a lack of a clear accumulative theoretical growth and continue as follows: "No line of theoretical development can be found that leads to a well-developed body of knowledge. The study of crime is characterized by a number of divergent theoretical perspectives that exist in relative isolation from one another" (p. 38). Quinney and Wildeman (1977) distinguish five theoretical perspectives in the development of criminology namely: (I) early and classical criminological thought, (2) nineteenth-century sociological criminology, (3) nineteenth-century biological criminology, (4) twentieth-century eclectic criminology, and (5) twentieth-century sociological criminology.
72

Impediments in the actualization of effective education for coloureds during the period 1910-1989

Filander, William John 06 1900 (has links)
Educational Studies / D.Ed. (History of Education)
73

Influência da cigarrinha-das-raízes (Mahanarva fimbriolata) e da adubação na qualidade do caldo e da canade- açúcar / Influence of froghopper-root (Mahanarva fimbriolata) and nutrition on the quality of the sugar cane juice

Pavão, Marcos Antônio 20 September 2012 (has links)
Made available in DSpace on 2016-06-02T18:57:42Z (GMT). No. of bitstreams: 1 4638.pdf: 6854394 bytes, checksum: f13771d01ee95a61cdbbd8b47f613fca (MD5) Previous issue date: 2012-09-20 / Brazil is the world's largest producer of sugar, a product whose specifications are somewhat dictated by the market. One of the important characteristics for sugar relates to its color. Sugars with less color index represent greater value and are preferred by buyers. Manufacturing a white crystal sugar with low cost need is a good quality raw material. The attack of pests and plant nutritional imbalance can interfere with the quality of raw material. The aim of this study was to evaluate the influence of organic fertilization, lack of fertilizer and root infestation by froghoppers in the production of substances that may compromise the quality of the broth, as result of in the defense system of the plant, with can interfere in the quality of juice. The experiment was conducted between the months of July 2010 to December 2011. A variety RB72454 was grown in pots of 50 liters in a randomized block design in split-split with six treatments: i) mineral fertilizer without froghopper ii) mineral fertilizer plus froghopper iii) organic compound without froghopper iv) organic compound froghopper v) without fertilization without froghopper and vi) no fertilization with froghopper; all treatments had four replicates and three harvest seasons. The samples were determined for BRIX, cane pol, pol juice, purity, reductor sugars (cane AR and AR juice), fiber, total reducing sugars (ART), starch, and phenolics. Data were subjected to analysis of variance and the test of Scott-Knott 5%. The results showed that the infestation of froghopper-roots in plots with mineral fertilizer and without fertilizer increased the content of phenolic compounds, compared to treatments without the presence of the insect. Plants from cane sugar fertilized with organic compost produced broth with lower content of phenolic compounds in presence with the absence of the insect. The infestation of leafhopperroots apparently caused greater amount of starch in the broth. / O Brasil é o maior produtor mundial de açúcar, produto cujas especificações são de certa forma ditadas pelo mercado. Uma das características importantes para o açúcar diz respeito a sua cor. Açúcares com menor índice de cor representam maior valor agregado e são preferidos pelos compradores. Para se fabricar um açúcar cristal branco com custo baixo, necessita-se de uma matéria prima de boa qualidade. O ataque de pragas e o desequilíbrio nutricional da planta podem interferir na qualidade da matéria prima. O objetivo deste trabalho foi avaliar a influência da adubação orgânica, a falta de adubação e a infestação das raízes por cigarrinhas-das-raízes na produção de substâncias que podem comprometer a qualidade do caldo, decorrentes do sistema de defesa da planta, e que podem interferir na qualidade do mesmo. O experimento foi conduzido entre os meses de julho de 2010 a dezembro de 2011. A variedade de cana-de-açúcar RB72454 foi cultivada em vasos de 50 litros no delineamento de blocos casualizados em parcelas sub-divididas com seis tratamentos: i) adubação mineral sem cigarrinhadas- raízes; ii) adubação mineral com cigarrinha-das-raízes; iii) composto orgânico sem cigarrinha-das-raízes; iv) composto orgânico com cigarrinha-das-raízes; v) sem adubação sem cigarrinha-das-raízes e vi) sem adubação com cigarrinha-das-raízes; com 4 repetições e 3 épocas de colheita. Nas amostras foram determinados BRIX, pol cana, pol caldo, pureza, açúcares redutores (AR cana e AR caldo), fibra, açúcares redutores totais (ART), amido e fenólicos. Os dados foram submetidos à análise de variância e ao teste de Scott-Knott a 5%. Os resultados mostraram que a infestação por cigarrinhadas- raízes em parcelas com adubação mineral e sem adubação aumentou o teor de compostos fenólicos, em comparação aos tratamentos sem a presença do inseto. As plantas de cana-de-açúcar adubadas com composto orgânico produziram caldo com menor teor de compostos fenólicos tanto na presença com na ausência do inseto. A infestação por cigarrinha-das-raízes aparentemente ocasionou maior quantidade de amido no caldo.
74

MALHAS DE SOMBREAMENTO FOTOSELETIVAS NO CRESCIMENTO E PRODUÇÃO DE ALFACE HIDROPÔNICO / PHOTOSELECTIVE SHADING NETS ON GROWTH AND PRODUCTION OF HYDROPONIC LETTUCE

Pinheiro, Renes Rossi 16 January 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The quality of light can alter morphogenesis of plants through a series of processes mediated by light receptors, the use of nets with different spectral characteristics in the cultivation of certain vegetable crops has become very common in recent years. Against the great influence that the solar radiation on plants, accomplished this research with the objective of evaluating the effect of intensity and spectral quality of light transmitted through the netting photoselectives in the growth and development of curly lettuce plants, as well as in microclimatic elements in a protected environment. The experiment featured four microhabitats: control - without net, net-term Aluminet reflector; Chromatinet netting blue and red, all with 35% shading, fixed at 0.90 m above the bed cultivation. The study was conducted in two stages, the first assessing the effect of net in the development of lettuce seedlings cultivar 'Solaris' floating produced hydroponically in winter season, rated the characteristics: number of leaves, leaf area, and fresh biomass dried roots, stems and leaves, stem length, why shoot / root and specific leaf area, and the second step verifying the influence of nets in growth and development, as well as the anatomy and physiology of lettuce cultivars 'Vera' 'Vanda' and 'Solaris' hydroponically-type solution of laminar flow bench during final production. The growth evaluations were done every seven days in two cropping seasons, autumn and winter, and the parameters were evaluated: number of leaves, leaf area, stem length, fresh weight and dry leaf and root dry weight. At the end of the production cycle were evaluated the anatomical and physiological parameters, which were stomatal density and morphology as well as the pigment content in lettuce leaves. With these results it is evident that the different nets modify microclimatic elements, presenting differences spectral transmittance, absorbance and reflectance. In the seedling stage thermo-reflective and red mesh showed a higher accumulation of biomass in lettuce compared to the environment without net and blue net. At the stage of final production bench observed that the cultivation environment promotes anatomical and physiological changes in lettuce and the environment without shading net showed higher dry biomass. In both steps the experimental blue net showed lower development of lettuce compared to other environments. / A qualidade de luz pode alterar a morfogênese das plantas por meio de uma série de processos mediados por receptores de luz. A utilização de malhas com diferentes características espectrais no cultivo de algumas espécies olerícolas tornou-se muito comum nos últimos anos. Diante da grande influência que a radiação solar exerce sobre os vegetais, realizou-se esta pesquisa com o objetivo de avaliar o efeito da intensidade e da qualidade espectral da luz transmitida pelas malhas fotoseletivas no crescimento e desenvolvimento de plantas de alface crespa, assim como nos elementos microclimáticos em ambiente protegido. O experimento contou com quatro microambientes: testemunha sem malha; malha Aluminet termo-refletor; malha Chromatinet azul e malha Chromatinet vermelha, todas com 35% de sombreamento, fixadas a 0,90 m acima dos leitos de cultivo. O estudo foi conduzido em duas etapas distintas, a primeira avaliando o efeito das malhas no desenvolvimento de mudas de alface cultivar Solaris‟ produzidas em sistema hidropônico floating na estação do inverno, avaliado as características: número de folhas, área foliar, fitomassa fresca e seca de raízes, caules e folhas, comprimento do caule, razão parte aérea/raiz e área foliar específica, e a segunda etapa verificando a influência das malhas no crescimento e desenvolvimento, assim como na anatomia e fisiologia de plantas de alface cultivares Vera‟, Vanda‟ e Solaris‟ em sistema hidropônico do tipo fluxo laminar de solução na fase de bancada de produção final. As avaliações de crescimento foram feitas a cada sete dias em duas épocas de cultivo, outono e inverno, e os parâmetros avaliados foram: número de folhas, área foliar, comprimento do caule, fitomassa fresca e seca de folha e fitomassa seca de raiz. Ao final do ciclo de produção avaliou-se os parâmetros anatômicos e fisiológicos, que foram: morfometria e densidade estomática assim como o teor de pigmentos nas folhas de alface. Com os resultados obtidos fica evidente que as diferentes malhas modificam os elementos microclimáticos, apresentando diferenças espectrais de transmitância, absorbância e refletância. Na fase de muda as malhas termo-refletor e malha vermelha apresentaram maior acúmulo de fitomassa em plantas de alface comparado ao ambiente sem malha e malha azul. Na fase de bancada de produção final observou-se que o ambiente de cultivo promove alterações anatômicas e fisiológicas em plantas de alface e o ambiente sem malha de sombreamento apresentou maior acúmulo de fitomassa. Em ambos as etapas experimentais a malha azul apresentou menor desenvolvimento das plantas de alface comparado aos demais ambientes.
75

A comparison of the epidemiology of low back pain in Indian and Coloured communities in South Africa

Docrat, Aadil January 1999 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, at echnikon Natal, 1999. / In order to investigate low back pain in an Indian and a Coloured community in South Africa, a population-based epidemiological survey was carried out in which 1 000 subjects were interviewed (500 Indians and 500 Coloureds). Subjects were selected using the Systematic Random Sampling method. A pre-tested questionnaire, designed by the researcher, was used to elicit information about the subjects' demography, general characteristics and details regarding low back pain (incidence, prevalence, severity, disability, treatment). Only subjects 18 years or older who were permanent residents of the 2 suburbs were included in the study. The author carried out the interviews personally / M
76

Algoritmo de conversÃo de Redes de Petri coloridas para Ladder Logic Diagram (LLD) / Algorithm Converting Colored Petri Nets for Ladder Logic Diagram (LLD)

Jonatha Rodrigues da Costa 28 January 2014 (has links)
Neste trabalho à apresentada uma proposta de conversÃo de modelos de cÃlulas de manufatura (FMS) em Redes de Petri Coloridas (RPC) para Ladder Logic Diagram (LLD). Explora-se modelos de RPC controlados - construidos usando-se como metodologia de controle supervisÃrio as RestriÃÃes de Controle sobre Cores Decompostas (RCCD) - e modelos nÃo controlados. Enfatiza-se a transformaÃÃo de RPC nÃo controlada para LLD e a facilidade de inclusÃo do controle. Os resultados aqui descritos demonstram que a metodologia facilita o trabalho de um programador de CLP em LLD minimizando os possÃveis erros durante a fase de programaÃÃo. Para exemplificar a metodologia foi desenvolvido um conversor de RPC para LLD, produzido em ambiente JAVA, afim de evidenciar a dinÃmica de conversÃo. Para a validaÃÃo dos resultados do conversor à usado um robà articulado vertical controlado via CLP, que opera comparativamente com e sem supervisÃo, o qual fora modelado primeiramente em RPC sem supervisÃo, depois aplicada a tÃcnica RCCD, a supervisÃo e a conversÃo para LLD. / In this dissertation, is presented a proposal of conversion of models of manufacturing cell (FMS) from Colored Petri Nets (CPN) to Ladder Logic Diagram (LLD). It explores the controlled CPN models - constructed using the methodology of supervisory Control Restrictions on Decomposed Colors (CRDC) - and not controlled models. It emphasizes the transformation of CPN not controlled for the LLD and ease for inclusion of control. The results described herein demonstrate that the methodology facilitates the work of a PLC programmer in LLD minimizing possible errors during the programming phase. To illustrate the methodology we developed a converter from CPN to LLD, produced in JAVA, in order to clarify the dynamic conversion environment. To validate the results of the converter, is controlled by PLC, a vertical articulated robot which works compared with and without supervision which had been firstly modeled in CPN without supervision, then applied to CRDC, the supervision and the conversion technique for LLD.
77

O papel da adenosina como reguladora do fluxo sanguíneo em ratos espontaneamente hipertensos jovens e adultos: efeitos do treinamento físico / The role of adenosine as blood flow regulator in SHR: fisical exercise effect

Juliana Gonçalves de Barros 05 November 2009 (has links)
INTRODUÇÃO: Exercícios físicos são utilizados como terapia nãofarmacológica para o tratamento da hipertensão arterial e o treinamento físico (TF) por natação é reconhecido por produzir remodelamento cardíaco em animais experimentais. Entretanto, a ação vasodilatadora da adenosina (ado) resultante do exercício físico como prevenção e tratamento da hipertensão é pouco explorada. OBJETIVO: Avaliar remodelamento cardíaco e papel da adenosina na distribuição do fluxo sanguíneo para o miocárdio após treinamento físico em SHR. MÉTODO: 28 SHR machos babies e adultos foram submetidos ao TF aeróbio de natação, durante 10 semanas (5x/sem - 1h/dia). Foram utilizados protocolos de microesferas coloridas para avaliar fluxo sanguíneo, técnicas de morfologia para avaliar hipertrofia cardíaca e análises bioquímicas para verificar atividade de enzimas envolvidas na formação de adenosina. RESULTADOS: TF por natação atenuou a evolução da HA em SHR babies (S: 145±2; T: 140±2 mmHg), promoveu bradicardia de repouso em SHR adultos (S: 340±4; T: 321±6 bpm) e desenvolveu HC nos dois grupos (TB: 12%; TA: 10%). Na condição basal, o TF aumentou o FS coronário em SHR babies (S: 4745±2145; T: 6970±2374 mi/coração) e maior resposta vasodilatadora à infusão de adenosina foi observada (S: 18946±6685; T: 25045±7031 mi/coração). Nesse grupo o TF promoveu maior atividade da enzima 5-nucleotidase, levando à maior formação de adenosina (S: 0.45±0.09; T: 1.01±0.05). CONCLUSÃO: O TF de natação, além de desenvolver HC e apresentar maior hidrólise de AMP, promoveu aumento no FS coronário, sendo mostrado que desempenha um importante papel na regulação da hipertensão / ABSTRACT: Exercise training (ET) has been used as non-pharmacological therapy for hypertension treatment and the swimming physical training is recognized for yield cardiac remodeling in experiments. However, little is known on the effects of adenosine (Ado) resulting from ET as hypertension prevention and treatment. OBJECTIVE: To evaluate cardiac remodeling and the role of adenosine in cardiac blood flow distribution (BF) to the myocardium after aerobic ET on SHR. METHODS: 28 male SHR, babies and adults, were submitted to swimming training protocol during 10 weeks (5 times a week 1 h a day). Colored micro spheres protocols were used to evaluate blood flow, morphological techniques were used to evaluate cardiac hypertrophy and biochemical analysis were performed to verify enzyme activity in the adenosine formation. RESULTS: ET attenuated the evolution of hypertension in babies SHR group (S: 145±2; T: 140±2 mmHg), HR was lower in adults SHR (S: 340±4; T: 321±6 bpm) and CH increased in both groups (TB: 12%; TA: 10%). At basal condition, BF was increased in trained babies (S: 4745±2145; T: 6970±2374 mi/heart) and higher vasodilatation response were observed due to adenosine infusion (S: 18946±6685; T: 25045±7031 mi/heart). In this group, the ET promoted a higher 5- nucleotidase enzyme activity leading to a higher adenosine formation (S: 0.45±0.09; T: 1.01±0.05). CONCLUSION: The swimming training developed CH as well as increased adenosine formation, leading to higher coronary blood flow, being demonstrated its important role in hypertension regulation
78

Preparação e caracterização de um novo sistema vítreo multicomponente a base de óxido de boro / Preparation and characterization of a new system base multicomponent glasses boron oxide

André Diniz Rosa da Silva 11 March 2013 (has links)
Vidros são materiais atraentes do ponto de vista científico e tecnológico, em especial porque algumas composições químicas permitem a fabricação em larga escala e/ou podem apresentar propriedades físico-químicas que os tornam candidatos promissores para aplicações como meio ativo para lasers, filtros ópticos, fibras ópticas, blindagens mecânicas ou como objeto de decoração ou utensílios domésticos ou como elemento para a construção civil, entre outras. Um dos desafios em preparar novas composições de materiais vítreos é garantir que não apareça o fenômeno da devitrificação. Este trabalho foi realizado com o objetivo de preparar e caracterizar uma nova matriz multicomponente, a base de óxido de boro, livre do fenômeno de cristalização. A matriz [50B2O3 - 15ZnO - 10PbO - 8MgO - 6K2O - 2Al2O3 - 2Nb2O5 - 5Si2O - 2Na2O] %wt pura e dopada com 0,1% mol de íons de metais de transição (MnO2, Fe2O3, CoO, NiO, CuO e CdCl2), foram preparadas em forno elétrico de atmosfera aberta usando cadinho de platina e caracterizadas usando as técnicas de: difração de raios X, análise térmica, densidade, pelo princípio de Arquimedes, microdureza Vickers, colorimetria, absorção óptica no intervalo ultravioleta-vísivel (UV-Vis) e transmissão óptica na região do infravermelho (FTIR). Resultados de difração de raios X confirmaram o caráter não cristalino das amostras vítreas. A adição de dopantes levou a mudança no número de coordenação na rede borato. Resultados de absorção óptica evidenciaram que a nova matriz desenvolvida com a adição de íons de metais de transição absorvem na região do visível e infravermelho próxima. Esses vidros tem potencial de aplicação na indústria de produtos decorativos e como filtros ópticos. / Glasses are attractive materials on a scientific and technologic point of view especially because some of their chemical compositions can provide a large scale production and/or may present physicochemical properties that them become promising candidates for applications as laser active environments, optical filters, optical fibers, mechanical shielding, adornment, domestic tools or construction stuff, among others. One of the challenges in preparing new compositions of glassy materials is to ensure that does not appear the phenomenon of devitrification. This work was carried out in order to prepare and characterize a new multicomponent glassy matrix, the basis of boron oxide, free from crystallization phenomenon. Pure glassy samples of [50B2O3 - 15ZnO - 10PbO - 8MgO - 6K2O - 2Al2O3 - 2Nb2O5 - 5Si2O - 2Na2O % wt] and 0.1% mol of transition metal ions (MnO2, Fe2O3, CoO, NiO, CuO e CdCl2) doped were prepared in open atmosphere electric furnace using platinum crucible and characterized using x-ray diffraction, thermal analysis, density evaluation from Archimedes principle, Vickers microhardness measurements, colorimetry, UV-VIS optical absorption and IR optical transmission. X-ray diffraction results confirmed non-crystalline character of the vitreous samples. Dopants addition led to changing on the coordination number of the borate network. Optical absorption results showed that the new glassy matrix developed with addition of transition metal ions absorb in the visible and near infrared range. These glasses may have potential applications in decorative products and as optical filters.
79

Benadeling van leerders en opvoeders in laerskole in Eldoradopark: 'n krities-linguistiese perspektief

Allie, J. J. 31 March 2009 (has links)
D.Litt. et Phil. / This study focuses on disadvantaged learners and educators in primary schools in Eldorado Park. It focuses, from a critical-linguistic perspective, on the injustice through language that occurs in some communities in South Africa that affects both learners and educators. The research is confined to the primary schools of Eldorado Park to elucidate the specific problems related to the disadvantage that is experienced by the community. Integration is a reality in most South African schools. Implementation of the integration and transformation in schools is the responsibility of the education authorities, but in practice especially that of the educators who are directly involved with the education of every learner irrespective of the language- or cultural background. Educators need help and assistance with this. Presently educators in many areas of our country are struggling on their own to address hindering factors in integrated classrooms, with very little assistance from the authorities. The scenario in some schools in Eldorado Park is described and some hindering factors identified and discussed. The role of language in education will be looked at through a descriptive study. The researcher will also look at lessons to be learnt from existing research. The implications of how some officials employed by the Department of Education interpret and implement education policies, cannot be separated from this. Eldorado Park is a former “Coloured township” in the south west of Johannesburg, a product of the former government’s apartheid policy, more specifically the Group Areas Act. The area, including Klipspruit-West, has eighteen primary schools with approximately 18 000 learners enroled in the primary schools. Some of the schools are parallel medium schools with English or Afrikaans as the medium of instruction and first additional language. Many schools are changing, or have done so already, to English medium schools. Learners from almost all language and cultural backgrounds have been admitted to schools in the area. Learners from the informal settlements next to Eldorado Park, have flocked to the schools over the past years. These learners usually have English as their medium of instruction with Afrikaans as their first addisional language at school. English is not the home language of many learners, but their second-, third- or even fourth language. Findings and recommendations from this research could help to address the special needs of integrated classrooms and to improve conditions for both learners and educators.
80

A report on the comparative performance of coloured and European factory workers on four tests of ability

Gough, Margaret Frances January 1947 (has links)
This thesis is a report on the results or four psychological tests, applied to two groups or workers in Port Elizabeth factories; the one group consisting of European, the other of Coloured workers. The abilities selected for testing were believed to be necessary, to some extent, in certain Industrial operations.

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