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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.
81

Political Poison: Agent Orange in Congress 1940-1991

Webb, Jamie Pauline 01 May 2019 (has links)
This paper examines the evolution of government policy through Congressional debate and citizen involvement on the topic of Agent Orange. Use of primary sources from newspaper and journal articles, Congressional records, scientific studies, and press releases and some secondary literature by scholars from multiple disciplines builds a picture of the ongoing debate of Agent Orange and its two component herbicides from circa 1940 to 1991. Within this paper are four primary focuses, divided into three parts. First, the Congressional discussions prior to 1970 of 2,4-D and 2,4,5-T, the two herbicides that comprise Agent Orange. Second and third, discussed in the same section, the involvement of the scientific community and the ratification of the Geneva Protocol. Lastly, the movement after the Vietnam War for veteran benefits due to Agent Orange exposure.
82

Baseline study on condom usage, safe sexual practices and sexually transmitted diseases among men and women aged 15-60 years in Orange Farm, South Africa 2002: A retrospective analysis

Awuonda, George Otieno 15 May 2008 (has links)
Abstract: Background: The global estimated adult and child deaths from HIV/AIDS in 2006 were 2.9 million and those living with HIV stood at 39.5 million. Of the HIV deaths, 72% (2.1 million) occurred in Sub-Saharan Africa (SSA). Two thirds (63%) of all adults and children with HIV globally live in, with its epicenter in Southern Africa. One third (32%) of all people with HIV globally live in Southern Africa and 34% of all deaths due to AIDS in 2006 occurred there. In South Africa, a total of 5.5 million people, including 240,000 children younger than 15 years, were living with HIV in 2005. HIV data gathered in the country’s antenatal clinic surveillance system suggest that HIV prevalence has not yet reached a plateau. There is a continuing trend nationally in HIV infection levels among pregnant women attending public antenatal clinics: from 22.4% in 1999 to 30.2% in 2005 (a 35% increase). Aim: The aim of this study was to assess sexual practices, the prevalence of condom usage and sexually transmitted diseases, and their associations among 930 men and women aged 15-60 years in Orange farm South Africa. Objectives: 1. To determine condom usage among males and females aged 15–60 year old. 2. To determine the number of new partners, short-term partners and unprotected sexual acts in this particular age group of men and women. 3. To assess the prevalence of sexually transmitted diseases in this age group. 4. To assess the relationship between sexual practices and sexually transmitted diseases in this community. Methods: The project was a secondary data analysis of a population-based, cross-sectional study was conducted in Orange Farm, South Africa in 2002. The original study involved 930 men and women respondents. A two-stage random sampling technique was used to select households. A self-weighting random sample of twenty households was chosen from clusters of 15 households. All men and women aged 15 to 60 years, who slept in the selected households the night before the study team’s visit, were eligible for inclusion in the study. The main focus of this secondary study was to analyze the baseline data collected for the level and risk factors for sexually transmitted diseases in this age group. All 930 men and women were included in the analysis. Results: The risk factor under consideration viz: condom usage was not optimal, and the prevalence of sexually transmitted disease is high in this population with HIV prevalence at 21.8%. Women in the age-group 15-24 years were disproportionately more affected by HIV in this community as compared to men. Among the HIV positive respondents, 61.8% had at least single or over 2 non-spousal partners in the last year. At the time of the interviews, 34.7% had never used condoms and 84.3% did not use condoms in any of the sexual episodes of the last month. Conclusion: An important goal is to practice partner reduction and to encourage especially those who are single to use condoms consistently. Further qualitative research on sexual behaviours involving focus group discussions, in-depth interviews or participant observation should be conducted in this community to complement the quantitative methods. They produce results that directly represent how people feel and provide information on behaviour through the observation of events and activities.
83

Agroclimatology: maize yields in the Orange Free State

Gillooly, Jane Frances 05 February 2015 (has links)
A Dissertation submitted to the Faculty of Science, University of the Wfitwatersvand, Johannesburg for the Degree of Master of Science. Johannesburg, 1977,
84

A survey of the attitudes of transescent students of Pinellas County toward the Florida prevocational home economics curriculm

Riggs, Linda Clark, Unknown Date (has links)
No description available.
85

El subsistema lingüístico Nadsat y su traducción a seis lenguas europeas: (alemán, francés, catalán, castellano, italiano y ruso)

Pina Medina, Víctor Manuel 25 March 1997 (has links)
No description available.
86

Avaliação horitcultural da laranjeira \'Folha Murcha\', tangerineira \'Satsuma\' e limeira ácida \'Tahiti\' sobre doze porta-enxertos / Horticultural evaluation of Folha Murcha sweet orange, Satsuma manadarin and Tahiti lime on twelve rootstocks

Cantuarias-Avilés, Tatiana Eugenia 10 August 2009 (has links)
A citricultura brasileira está fundamentada predominantemente sobre apenas um cultivar porta-enxerto, o limoeiro Cravo, e explora poucos cultivares copa, de uma maneira geral. Desse modo, o setor citrícola fica limitado na abertura de suas fronteiras de exportação para frutas frescas por estar baseado em um pequeno número de cultivares. Além disso, ao redor de 80% dos plantios estão reunidos em uma região compreendida por quase 600 mil ha, de forma concentrada, no Estado de São Paulo e sul do Triângulo Mineiro. Esses fatos também acarretam em grande vulnerabilidade fitossanitária, com ameaças crescentes de pragas e doenças, levando à redução da produtividade e ao acréscimo dos custos de implantação e condução dos pomares. A Clorose Variegada dos Citros (CVC) ou amarelinho, causada pela bactéria Xylella fastidiosa, é um exemplo destas ameaças. De elevada severidade em laranjas doces, causa redução no tamanho dos frutos, tornando-os inaptos para a comercialização in natura ou para produção de suco concentrado. Recentemente, as perdas em produção causadas pela CVC têm sido estimadas em até 10-14% da safra comercializável. Atualmente, o manejo da CVC está baseado na utilização de mudas sadias, poda de ramos afetados, e controle dos vetores. Além dessas medidas, é importante manter os tratos culturais exigidos no pomar. Entretanto, a utilização de cultivares resistentes é estratégia imprescindível para convivência com a doença em longo prazo. Este trabalho buscou avaliar o desempenho horticultural da laranjeira Folha Murcha, da tangerineira Satsuma cv. Okitsu e da limeira ácida Tahiti sobre doze porta-enxertos. Tangerina Satsuma cv. Okitsu e lima ácida Tahiti são espécies não sintomáticas em relação à CVC e tornam-se opções com potencial de exploração em pequenas propriedades. A laranjeira Folha Murcha tem demonstrado maior tolerância à CVC comparativamente aos demais cultivares de laranja doce. Os experimentos foram conduzidos na Estação Experimental de Citricultura de Bebedouro, EECB, (SP), e instalados em 2001. Em todos os experimentos foram avaliados o desenvolvimento vegetativo, produção e qualidade dos frutos (por no mínimo três safras) em cada combinação copa/porta-enxerto. Avaliações adicionais a respeito da tolerância à CVC foram realizadas no experimento de laranjeira Folha Murcha. Nos experimentos conduzidos sem irrigação, foi avaliada a tolerância ao déficit hídrico das copas usando duas metodologias: avaliação visual subjetiva e medição direta da coloração das folhas. Na limeira ácida Tahiti, a coloração externa dos frutos de exportação foi quantificada em função de variáveis colorimétricas, definindo-se uma metodologia quantitativa alternativa ao sistema atual de classificação dos frutos, baseado apenas na apreciação visual subjetiva. A avaliação horticultural de copas de laranjeira Folha Murcha, limeira ácida Tahiti e tangerineira Satsuma cv. Okitsu em doze porta-enxertos permitiu identificar porta-enxertos alternativos ao limoeiro Cravo, sendo estes os trifoliatas Flying Dragon, FCAV e Rubidoux. / Brazilian citriculture is mainly based on one rootstock cultivar, the Cravo Rangpur lime, exploring a restricted number of scion cultivars. This situation limits the expansion of citrus production for fresh fruit export, due to the limited number of cultivars in use. Besides, near 80% of citrus orchards are located in an area of approximately 600,000 ha, in the São Paulo State and the southern region of the Minas Gerais State. These facts also impose a large phytossanitary vulnerability to citrus production, due to the increasing threats of pests and diseases outbreaks, that cause productivity decrease and higher costs for orchard establishment and management. The Citrus Variegated Chlorosis (CVC), caused by the xylem-limited bacterium, Xylella fastidiosa, is one example of such threats. This disease is extremely severe in sweet oranges, causing size reduction ad quality deterioration of fruits, that become unsuitable for fresh consume or juice processing. The losses associated to CVC have been recently estimated in 10-14% of the total comercial crop in São Paulo State. CVC management is currently based on the use of healthy nursery plants, pruning of injured branches and control of the vectors. In addition to these strategies, it is important to maintain adequate cultural practices for orchard management. Nonetheless, the utilization of resistant cultivars is an indispensable strategy to co-exist with the disease in the long term. This study was aimed to evaluate the horticultural performance of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime grafted onto twelve rootstocks. Okitsu Satsuma mandarin and Tahiti lime are assymptomatical species in relation to CVC, with potential to be produced in small areas. The Folha Murcha sweet orange has demonstrated high tolerance to CVC, when compared with other sweet orange cultivars. The trials were conducted at the Estação Experimental de Citricultura de Bebedouro, (EECB), and were planted in 2001. Evaluations of plant growth, yield and fruit quality were carried out in all the trials, during three years. In the Folha Murcha trial, additional evaluations of CVC tolerance were conducted. In the non-irrigated trials, tree water deficit tolerance was evaluated by two methods: visual assessment of water stress and direct leaf color measurements. In Tahiti lime, peel color of export fruits was measured and a quantitative methodology was defined as an alternative for current classification criteria, which are based on the subjective visual inspection of external fruit aspect. The horticultural evaluation of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime onto twelve rootstocks allowed to identify the trifoliate rootstocks Flying Dragon, Rubidoux and FCAV as alternatives to Cravo Limeira.
87

Hierarchical supramolecular assemblies based on host-guest chemistry between cucurbit[n]uril and azobenzene derivatives

Liu, Chenyan January 2019 (has links)
Cucurbit[8]uril (CB[8]) has attracted great interest in the cucurbit[n]uril (CB[\textit{n}]) family on account of its capability to simultaneously accommodate two guests inside its cavity, to form strong yet dynamic ternary complexes. Owing to the photo-induced \textit{trans} to \textit{cis} isomerisation property, azobenzene (Azo) derivatives have been widely employed in several host-guest systems, leading to various light-responsive materials. This thesis focuses on CB[8]-based ternary complexes, especially those involving Azo derivatives. These systems can be exploited as a platform to hierarchically fabricate supramolecular constructs, including crystalline structures and composite materials. Specifically, novel morphology-controlled (1D needle-like, 2D sheet-like) crystals have been prepared by adjusting the assembly of Azo-CB[8] complexes, which can be further developed to oriented macroscopic free-standing crystalline pillars grown from a glass surface. Next, a composite micelle-nanoparticle complex has been prepared utilising Azo-CB[8] assemblies, which demonstrates $\sim$90$\%$ efficiency in surfactant recycling. Finally, an organic CB[8]-mediated hydrogel reinforced by inorganic nanowires has been prepared. This hybrid structure shows increased stiffness due to various supramolecular interactions. Chapter 1 gives a brief introduction to CB[\textit{n}] host-guest chemistry with emphasis on CB[\textit{n}]-based crystalline structures and CB[8] ternary complexes. Recent progress of Azo-based host-guest chemistry is then reviewed. In addition, shape-controlled crystals formed \textit{via} supramolecular interactions are discussed at the end of the chapter. Chapter 2 focuses on the crystalline structure of the 1:2 homoternary complex formed between CB[8] and a methyl orange (MO) guest, which is the fastest CB[8]-based crystallisation to date. As a commonly used pH indicator, MO possesses an azobenzene moiety with both an electronically positive amino group and an anionic sulfonate group. At low pH values, formation of the homoternary complex 2MO@CB[8] occurs, serving as a 'tectonic' building block, which rapidly stacks into a herringbone arrangement. The intermolecular and intercomplex interactions inside 2MO@CB[8] crystals are discussed, whereby the CB[8] macrocycle orients the electrostatic charges on MO guests resulting in the repulsive interactions being shielded; this in turn leads to fast electrostatically-driven crystal growth. The 2MO@CB[8] system provides a promising approach for designing ultrarapid crystallisation systems derived from CB[\textit{n}] host-guest complexes. Moreover, the host-guest chemistry between CB[8] and a variety of Azo derivatives with different functional groups is discussed, demonstrating the influence of guest structures on their crystalline behaviours. Chapter 3 further explores the mechanism of 2MO@CB[8] crystallisation through a series of experimental and computational methods. Control over the crystal shape, length and growth rate can be achieved in a facile manner whilst maintaining the same (internal) unit cell. Therefore, the properties of the macro-scale crystals can be tuned at the molecular level through adjusting the assembly of 2MO@CB[8] building blocks. For example, tuning the ionic strength of the solution enables a second growth dimension, yielding 2D crystals with sheet-like and more complex morphologies. Furthermore, our understanding of oriented electrostatics provided by the homoternary tecton can then be exploited to prepare oriented macroscopic free-standing crystalline pillars grown from a glass surface at room temperature. Next, CB[8] ternary complexes have been employed as 'bridges' to link (organic) soft and (inorganic) hard materials together, resulting in composite materials. In chapter 4, a micelle-nanoparticle complex (\textbf{MNC}) structure has been assembled \textit{via} host-guest interactions between Azo-functionalised, cargo-loaded micelles and magnetic SiO$_2$ nanoparticles (NPs) functionalised with CB[8] catenanes. Owing to the photo-responsive and magnetic properties, \textbf{MNCs} can be exploited to recycle detergents (micelles) from aqueous solution. This is followed by the controlled release of the encapsulated hydrophobic molecules inside the micelle cavity. In this process, both the micelles and NPs can be recycled efficiently. The novel \textbf{MNC} structure provides a promising approach to recycle versatile drug carriers through host-guest chemistry. Chapter 5 introduces a CB[8]-based hydrogel in which inorganic nanowires (NWs) are employed to enhance the gel stiffness. The supramolecular hydrogel is comprised of methylviologen-functionalised poly(vinyl alcohol) (PVA-MV), hydroxyethyl cellulose with naphthyl moieties (HEC-Np) and CB[8]. The gel structure is effectively enhanced by the framework supporting effects of CePO$_4$ NWs and additional hydrogen bonding interactions between NWs and PVA-MV/HEC-Np polymers. The high aspect ratio NWs serve as a 'skeleton' for the network, providing extra physical crosslinks. This results in a single continuous phase hybrid supramolecular network with improved strength, showcasing a general approach to reinforce soft materials. Finally, this thesis closes with a summary and perspective chapter, concluding the present work and highlighting an insight towards future work. Utilising CB[8] ternary complexes, various supramolecular constructs can be prepared through hierarchical self-assemblies, leading to a wide variety of composite systems and functional materials in the future.
88

Pectin and galacturonic acid from citrus wastes

Hossein Abbaszadeh, Amir January 2009 (has links)
In this work an investigation to find new method of extraction of pectin from orange peel with shortening time of extraction is carried out. Pectin was extracted from dried orange peel at higher temperature by employing stainless steel reactors. In this investigation the effect of extraction conditions (temperature: 120, 150, 200°C; extraction time: 5, 15, 30 min) with sulphuric acid, on the yield and purity of citrus pectin was performed. Moreover, optimizing other methods of extraction and analyzing of pectin is tested. In addition, effect of adding special reagent such as Sodium polyphosphate to extract solvent examined. Furthermore, two different acids are used for extraction and the results are compared as described. Pectin is solubilized by HCl and H2SO4 at different concentrations, retention time and temperature. The effect of extraction conditions (pH: 1.5 to 2; temperature: 80 to 90°C; extraction time: 1 to 3 hours) with sulphuric acid, on the yield and purity of citrus pectin was carried out. The solubilized pectin is precipitated from the solution by using organic solvents such as 2-propanol and ethanol and then analysis was done with different methods such as carbozole and meta-hydroxy-diphenyl method. A same test was run for hydrochloric acid and comparison between them was done. / Uppsatsnivå: D
89

Influência do consumo de suco de laranja sobre marcadores bioquímicos, imunológicos e de estresse oxidativo em pacientes com hepatite C crônica /

Lima, Cláudia Gonçalves de. January 2015 (has links)
Orientador: Thais Borges César / Banca: Lívia Gussoni Basile / Banca: Paulo Inácio da Costa / Banca: Thábata Koester Weber / Banca: Anderson Marliere Navarro / Resumo: O presente estudo teve como objetivo avaliar o efeito do consumo regular do suco de laranja nos parâmetros nutricionais, hemodinâmicos e bioquímicos de pacientes com hepatite C crônica. Participaram do estudo 66 indivíduos adultos de ambos os sexos, divididos em quatro grupos: Grupo com tratamento medicamentoso e com suco de laranja (MedSuco), Grupo sem tratamento medicamentoso e com suco de laranja (Suco), Grupo com tratamento medicamentoso e sem suco de laranja (Med) e Grupo sem tratamento medicamentoso e sem suco de laranja (Controle). Os participantes dos grupos Suco e MedSuco receberam 500 mL/dia de suco de laranja pasteurizado durante 8 semanas. As variáveis antropométricas utilizadas foram: peso, altura, dobras cutâneas do tríceps, bíceps, subescapular e supra ilíaca e circunferência da cintura. Para a avaliação hemodinâmica foram verificadas a pressão arterial sistólica e a diastólica, e para a avaliação dietética foi utilizado o registro alimentar, durante três dias alternados. Para a avaliação bioquímica foram realizadas dosagens de colesterol total, colesterol de HDL, triglicérides, glicemia de jejum, insulina, proteína C reativa, peroxidação lipídica, capacidade antioxidante, TNF-, interleucinas 6 e 10 e carga viral. Todas as avaliações foram realizadas antes e após o consumo do suco de laranja. Os resultados mostraram que após o consumo do suco de laranja, os pacientes do grupo Suco tiveram redução significativa do LDL-C (-9,9%), pressão arterial sistólica (-4.5%), insulina (-26.5%), índice HOMA (-32.0%), peroxidação lipídica (-68.5%), proteína C reativa (-48.8%) e TNF- (-11.7%), e aumento da capacidade antioxidante (1.2%); e os pacientes do grupo MedSuco tiveram redução significativa do LDL-C (-13.7%), pressão arterial sistólica (5.1%), HDL-C (-12.2%), peroxidação lipídica (-39.1%), proteína C reativa (-74.9%), TNF- (-8.8%) e carga viral (26.5%), e aumento da capacidade... / Abstract: This study aimed to evaluate the effect of regular orange juice consumption on nutritional parameters, hemodynamics and biochemicals of patients with chronic hepatitis C. The study included thirty-six adults of both sexes, divided into four groups: Group with drug treatment and orange juice (MedJuice), Group without drug treatment and with orange juice (Juice), Group with drug treatment and no orange juice (Med) and Group without drug treatment and no orange juice (Control). The participants of groups Juice and MedJuice received 500 mL / day of pasteurized orange juice for 8 weeks. The anthropometric variables were studied: weight, height, skin folds of the triceps, biceps, subscapular and suprailiac and waist circumference. For hemodynamic evaluation were found systolic and diastolic blood pressure, and for dietary assessment was used food records for three alternate days. For the biochemical evaluation were performed in total cholesterol, HDL cholesterol, triglycerides, fasting glucose, insulin, C-reactive protein, lipid peroxidation, antioxidant capacity, TNF-α, interleukins 6 and 10 and viral load. All evaluations were performed before and after consumption of orange juice. The results showed that after the consumption of orange juice, patients of Juice group had significant reduction in LDL-C (-9.9%), systolic blood pressure (-4.5%), insulin (-26.5%), HOMA index (-32.0%), lipid peroxidation (-68.5%), C-reactive protein (-48.8%) and TNF-α (-11.7%) and increase in antioxidant capacity (1.2%); and patients of MedJuice group had significant reduction in LDL-C (-13.7%), systolic blood pressure (5.1%), HDL-C (-12.2%), lipid peroxidation (-39.1%), C-reactive protein (-74.9% ), TNF-α (-8.8%) and viral load (26.5%) and increase in antioxidant capacity (2.5%). There was no significant decrease in anthropometric variables. Consumption of orange juice increased by 334.0% to intake of vitamin C and 63.6% folate intake of participants in the ... / Doutor
90

Período de incubação de Guignardia citricarpa em frutos de laranja 'Valência' e importância das pulverizações de cobre no controle da mancha preta /

Aguiar, Ronilda Lana. January 2011 (has links)
Resumo: A mancha preta dos citros (MPC), causada pelo fungo Guignardia citricarpa, produz lesões nos frutos que os depreciam para o mercado interno e os restringem para a exportação. O grande período de suscetibilidade dos frutos, em adição ao fato do patógeno causar infecções latentes, dificulta o entendimento do período de incubação da doença. O objetivo do trabalho foi determinar se o período de incubação da mancha preta do citros. Inoculou-se frutos de laranjeira 'Valência' em diferentes estádios fenológicos e também foi determinado a importância das pulverizações de fungicida cúprico, da fase de queda das pétalas e, até sete meses após, no controle da mancha preta dos citros. Os resultados obtidos indicaram uma relação linear negativa entre o período de incubação da MPC e o diâmetro dos frutos inoculados. O período de incubação em frutos inoculados, ainda imaturos (2,0, 2,5 e 3,0 cm de diâmetro), foi longo, sendo de 266 dias nos de menor diâmetro menor, enquanto que em frutos já desenvolvidos (5,0 e 7,0 cm de diâmetro) o período para expressão de sintomas foi mais curto, sendo de cerca de 30 dias. A mancha preta em frutos cítricos apresenta período de incubação variável, dependente do estádio fenológico em que os frutos tornaram-se infectados. A concentração do inóculo de Guignardia citricarpa não interfere no período de incubação da doença. Em relação à incidência da MPC, mesmo com seis pulverizações de cobre a cada 28 dias, 53,3% dos frutos expressaram sintomas da doença. Quanto à severidade, não há diferença de resposta entre os tratamentos. Portanto, os dados mostraram que as infecções precoces interferem na qualidade visual do fruto, porém não na produção. Com o crescimento dos frutos, as infecções interferem negativamente na produção, levando a um aumento na queda de frutos / Abstract: The citrus (Citrus spp.) black spot, caused by Guignardia citricarpa produces lesions on the fruit that depreciate the domestic market and to restrain them for export. The great period of susceptibility of the fruits in addition to the fact that the pathogen causing latent infection of complicates the understanding of the incubation period of the disease. The aim of this study was to determine the incubation period of the citrus black spot is constant or variable, inoculating fruits of 'Valência' orange at the different phenological stages and was also given the importance of copper fungicide sprays, stage of petal drop and up to seven months in the control of citrus black spot The results indicate a negative linear relationship between the incubation period of the CBS and the diameter of the fruits inoculated. The incubation period observed in fruits inoculated still immature (2,0, 2,5 and 3,0 cm diameter) was long, smaller in diameter occurred around 266 days, and fruits already developed (5,0 and 7,0 cm diameter) for the disease expression was shorter in diameter occurred in approximately 30 days. The citrus black spot has a variable incubation period depends on the phenological stages in which fruit is inoculated. The concentration of inoculum of Guignardia citricarpa not interfere with the incubation period of the disease. Regarding the incidence of CBS, even with six copper sprays every 28 days, 53.3% of the fruit expressed disease symptoms. For severity, there is no difference in response between treatments. Therefore, the data showed that early infections influence the visual quality of the fruit, but not in production. With the growth of the fruit, infections can affect negatively the production, leading to an increase in fruit drop / Doutor

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