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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.
161

Changes in Fruit and Vegetable Household Food Availability Among Low-Income Families over a One-Month Period of Time

Wells, Ann Alicia 16 December 2011 (has links) (PDF)
Objective: There is little evidence of how fruit and vegetable (FV) household food availability changes over a one-month period among low-income households. The objective of this study was to analyze how FV variety and sustainability changes over a 4-week period. Design: Inventories were conducted in low-income family households (n=49) once a week over a 4-week period. Trained researchers gathered the weights of all FV, including legumes, within the home. Previously determined mean container weights were subtracted to obtain the estimated weight of the FV. All weights were then converted to edible cups of FV, taking into account the weight that is removed when stems, peels, skins, and canning liquid are removed. Analysis: Variety was measured by analyzing the number of kinds of FV within the USDA subgroups (100% fruit juice, citrus fruits, other fruits, dark green vegetables, orange vegetables, dry beans and peas, starchy vegetables, and other vegetables) found in the home. In addition, sustainability was analyzed by the number of days into the future at which households can meet 100% of the FV recommendations. Data were combined for all households, according to the time points with the most amount of FV (HFV), the second-most amount of FV, the third-most amount of FV, and the least amount of FV (LFV) available in the household. Results: Vegetables, specifically canned vegetables, comprised the majority of all measurements taken throughout all inventories. When combined, the kinds of total FV decreased significantly from 25±1.1 kinds on HFV to 21.2±1.1 kinds on LFV (p<.0001). Days into the future at 100% of the fruit recommendation fell significantly from 11.4±0.1 days on HFV to 7.1±0.1 days on LFV (p<.0001). Total vegetables decreased significantly from 25.3±0.1 days on HFV to 19.1±0.1 days on LFV (p<.0001). Even at the peak of FV availability, dark green vegetables remained the lowest subgroup at 2.17±0.1 days and decreased to 1.6±0.1 days at LFV (p=0.01). Conclusions and Implications: Low-income households have greater variety of FV during the times when they have the most food resources compared to when they have the least food resources. The days into the future that the household FV supply could be maintained at 100% of the USDA's subgroup recommendation varies widely between subgroups, from about two days up to more than one month. Further research is needed to determine how to maintain subgroup variety and constancy of a FV supply throughout the month for low-income FV.
162

Índices de maturação, ponto de colheita e padrão respiratório de goiabas 'Kumagai' e 'Paluma'. / Maturation rates, harvest point and respiratory standard of the ‘kumagai’ and ‘paluma’ guavas.

Cavalini, Flavia Cristina 21 June 2004 (has links)
A goiaba é uma fruta altamente perecível, e o conhecimento de sua fisiologia pós-colheita é fundamental para o emprego adequado de tecnologias, visando aumentar o período de conservação. O presente trabalho foi realizado com os objetivos de determinar índices de maturação; verificar a influência dos estádios de maturação na qualidade pós-colheita e determinar o padrão respiratório para goiabas ‘Kumagai’ e ‘Paluma’. Primeiramente determinaram-se os índices de maturação e a influência de cinco estádios de maturação na qualidade pós-colheita dos frutos. Os frutos foram selecionados em cinco estádios de maturação segundo a cor da casca: Estádio 1: cor da casca verde-escura; Estádio 2: quebra da cor verde; Estádio 3: início da coloração amarela da casca; Estádio 4: cor da casca parcialmente amarela; Estádio 5: frutos com cor da casca totalmente amarela, em seguida, foram armazenados em câmara a 25 + 2ºC e 80-90% UR e avaliados quanto às mudanças físico-químicas e qualidade sensorial. Posteriormente determinou-se o padrão respiratório dos frutos, analisando-se a atividade respiratória, a produção de etileno e as mudanças físico-químicas após a colheita para os estádios 1, 2 e 3. A cor da casca e a firmeza foram consideradas os melhores índices de maturação para ambas as variedades. A variedade Paluma também apresentou o ratio como um bom índice de maturação. As variáveis físico-químicas apresentaram pouca variação entre os estádios de maturação após o amadurecimento, porém foram observadas diferenças significativas em relação à análise sensorial, sendo as melhores notas atribuídas aos estádios 4 e 5 na variedade Kumagai e para o estádio 5 na variedade Paluma. O ponto de colheita de goiabas ‘Kumagai’ não interferiu na firmeza da polpa, no teor de sólidos solúveis e no ratio ao final do período comercializável, apresentando os frutos do estádio 1 mais verdes, com menor teor de ácido ascórbico e maior acidez titulável. Em goiabas ‘Paluma’, o ponto de colheita não influenciou na cor da casca e no teor de sólidos solúveis. No geral, os frutos do estádio 1 apresentaram-se mais firmes, com menor teor de ácido ascórbico, mais ácidos, com cor da polpa mais clara e maior ratio. Tanto a variedade Kumagai quanto a Paluma apresentaram pico respiratório e de produção de etileno, independente do estádio de maturação, porém, estes ocorreram após o completo amadurecimento dos frutos. / Guava is a highly perishable fruit and its post harvest physiology knowledgement is fundamental for the proper technology use in order to increase the preservation period. The present study was accomplished to determine the maturation rates; to verify the influence of the maturation levels in the post harvest and to determine the respiratory standard for the Kumagai and Paluma guavas. At first, the maturation rates and the influence of five levels of maturation in the post harvest of the fruit were determined. The fruits were selected in five levels of maturation according to the color of the peel: Level 1: a dark green color peel; Level 2: loss of the green color; Level 3: start of the yellow color of the peel; Level 4: a partially yellow color of the peel; Level 5: a totally yellow color of the fruits, and then, they were kept in a chamber at a percentage of 25 + 2ºC and 80-90% UR and evaluated as to the physico-chemical changes and sensory quality. After that, the respiration standard of the fruits was determined, analyzing the respiration activity, the production of ethylene and the physico-chemical changes after the harvest for the levels 1, 2 and 3. The color and the firmness of the peel were considered the best maturation rates for both varieties. The variety Paluma also showed the ratio as to a good maturation level. The physico-chemical variables showed less variation between the maturation levels after the ripeness, however significant differences were observed in relation to the sensorial analysis, obtaining the best performance for the levels 4 and 5 in the Kumagai variety and for the level 5 in the Paluma variety. The harvest point of the Kumagai guavas did nor interfere in the firmness of the flesh, in the content of the soluble solids and in the ratio to the end of the commerceable period, showing greener fruits in level 1 with a less content of ascorbic acid and a high titled acidic. In the Paluma guavas, the harvest point did not influence in the color of the peel and the content of soluble solids. In general, the fruits of level 1 showed firmer with a less content of ascorbic acid, more acidic with a lighter color of the flesh and a higher ratio. As the Kumagai as the Paluma varieties showed a respiratory peak and ethylene production independent of the maturation ratio, however these occurred after the complete ripeness of the fruits.
163

Índices de maturação, ponto de colheita e padrão respiratório de goiabas 'Kumagai' e 'Paluma'. / Maturation rates, harvest point and respiratory standard of the ‘kumagai’ and ‘paluma’ guavas.

Flavia Cristina Cavalini 21 June 2004 (has links)
A goiaba é uma fruta altamente perecível, e o conhecimento de sua fisiologia pós-colheita é fundamental para o emprego adequado de tecnologias, visando aumentar o período de conservação. O presente trabalho foi realizado com os objetivos de determinar índices de maturação; verificar a influência dos estádios de maturação na qualidade pós-colheita e determinar o padrão respiratório para goiabas ‘Kumagai’ e ‘Paluma’. Primeiramente determinaram-se os índices de maturação e a influência de cinco estádios de maturação na qualidade pós-colheita dos frutos. Os frutos foram selecionados em cinco estádios de maturação segundo a cor da casca: Estádio 1: cor da casca verde-escura; Estádio 2: quebra da cor verde; Estádio 3: início da coloração amarela da casca; Estádio 4: cor da casca parcialmente amarela; Estádio 5: frutos com cor da casca totalmente amarela, em seguida, foram armazenados em câmara a 25 + 2ºC e 80-90% UR e avaliados quanto às mudanças físico-químicas e qualidade sensorial. Posteriormente determinou-se o padrão respiratório dos frutos, analisando-se a atividade respiratória, a produção de etileno e as mudanças físico-químicas após a colheita para os estádios 1, 2 e 3. A cor da casca e a firmeza foram consideradas os melhores índices de maturação para ambas as variedades. A variedade Paluma também apresentou o ratio como um bom índice de maturação. As variáveis físico-químicas apresentaram pouca variação entre os estádios de maturação após o amadurecimento, porém foram observadas diferenças significativas em relação à análise sensorial, sendo as melhores notas atribuídas aos estádios 4 e 5 na variedade Kumagai e para o estádio 5 na variedade Paluma. O ponto de colheita de goiabas ‘Kumagai’ não interferiu na firmeza da polpa, no teor de sólidos solúveis e no ratio ao final do período comercializável, apresentando os frutos do estádio 1 mais verdes, com menor teor de ácido ascórbico e maior acidez titulável. Em goiabas ‘Paluma’, o ponto de colheita não influenciou na cor da casca e no teor de sólidos solúveis. No geral, os frutos do estádio 1 apresentaram-se mais firmes, com menor teor de ácido ascórbico, mais ácidos, com cor da polpa mais clara e maior ratio. Tanto a variedade Kumagai quanto a Paluma apresentaram pico respiratório e de produção de etileno, independente do estádio de maturação, porém, estes ocorreram após o completo amadurecimento dos frutos. / Guava is a highly perishable fruit and its post harvest physiology knowledgement is fundamental for the proper technology use in order to increase the preservation period. The present study was accomplished to determine the maturation rates; to verify the influence of the maturation levels in the post harvest and to determine the respiratory standard for the Kumagai and Paluma guavas. At first, the maturation rates and the influence of five levels of maturation in the post harvest of the fruit were determined. The fruits were selected in five levels of maturation according to the color of the peel: Level 1: a dark green color peel; Level 2: loss of the green color; Level 3: start of the yellow color of the peel; Level 4: a partially yellow color of the peel; Level 5: a totally yellow color of the fruits, and then, they were kept in a chamber at a percentage of 25 + 2ºC and 80-90% UR and evaluated as to the physico-chemical changes and sensory quality. After that, the respiration standard of the fruits was determined, analyzing the respiration activity, the production of ethylene and the physico-chemical changes after the harvest for the levels 1, 2 and 3. The color and the firmness of the peel were considered the best maturation rates for both varieties. The variety Paluma also showed the ratio as to a good maturation level. The physico-chemical variables showed less variation between the maturation levels after the ripeness, however significant differences were observed in relation to the sensorial analysis, obtaining the best performance for the levels 4 and 5 in the Kumagai variety and for the level 5 in the Paluma variety. The harvest point of the Kumagai guavas did nor interfere in the firmness of the flesh, in the content of the soluble solids and in the ratio to the end of the commerceable period, showing greener fruits in level 1 with a less content of ascorbic acid and a high titled acidic. In the Paluma guavas, the harvest point did not influence in the color of the peel and the content of soluble solids. In general, the fruits of level 1 showed firmer with a less content of ascorbic acid, more acidic with a lighter color of the flesh and a higher ratio. As the Kumagai as the Paluma varieties showed a respiratory peak and ethylene production independent of the maturation ratio, however these occurred after the complete ripeness of the fruits.
164

A study of the relationship between the natural history of the Solanaceae species and the general and mental symptomatology of the Solanaceae remedies utilised in homoeopathy

Long, Bryan Henry January 2011 (has links)
Dissertation submitted in partial compliance with the requirements for the Master‟s Degree in Technology: Homoeopathy, Durban University of Technology, 2011. / Until recently, various attempts have been made to simplify the prescription process in homoeopathic prescribing. The doctrine of signatures, miasmatic theory, the homoeopathic repertory and more recently, kingdom analysis by authors such as Sankaran (1994) and Scholten (1993) are some of the attempts that have been made to understand the materia medica. With the materia medica constantly expanding and considering that plants make up a significant percentage of the materia medica (Kayne, 2006), it is evident that new systems of homoeopathic prescribing are continually needed to help practitioners both study the remedies and prescribe more accurately. Aim The Solanaceae plant family are an important and well utilised plant family in homoeopathy (Vermeulen, 2004). Considering this, it was felt that a study investigating the relationship of the natural history of the family to its general and mental symptoms be conducted in order to apply a previously unexplored research paradigm in order to create a greater understanding of Solanaceae remedies utilised in homoeopathy. The study conducted was a non empirical correlation study of the Solanaceae plant family‟s natural history and general and mental symptoms manifested in Solanaceae remedies utilised in homoeopathy. The aims of the study were to establish if commonalties existed between general and mental symptoms of individual remedies belonging the Solanaceae family and their natural histories, as well as to establish if collective commonalities and correlations existed between the general and mental symptoms and the natural history of the Solanaceae family as a whole. Methodology The homoeopathic remedies obtained from the Solanaceae family of plants for the study were analysed in terms of rubric representation (size) using homoeopathic software packages, Radar 10.4 (Archibel, 2009b) and v Encyclopedia Homoeopathica (Archibel, 2009a) a sample selection was chosen. This selection was analysed in terms of general and mental rubrics. Qualitative thematic analysis was used to establish commonalities in keyword concepts between the respective natural histories of the studied family and their respective general and mental symptoms. Keywords obtained from data tables which included criteria such as habitat and distribution, plant description, active principles (primary alkaloids), uses, physiological action if ingested, historical significance, mythology and toxicology were subjected to thesaurus consultation and tabulated in an attempt to identify synonyms relating to the general and mental symptoms of individual remedies of the sample group in the study. This facilitated in the grouping of similar themes. Once commonalities pertaining to each individual species and remedy was further tabulated and discussed in terms of keywords relating to their natural histories, a collective analysis of common correlations between the plant family as a whole was performed. Results Common themes related to general and mental symptoms and to the natural histories of species in the study included “aggression” found in Atropa belladonna, “depression” found in Solanum dulcamara, “anxiety” found in Datura stramonium, “confusion” found in Hyoscyamus niger, “burns” found in Capsicum annuum, “ convulsions” found in Nicotiana tabacum , “ hallucinations” found in Mandragora officinarum and “delirium” found in Solanum nigrum. Common themes relating to general and mental symptoms and the natural history of the Solanaceae plant family as a whole included convulsions, hallucinations, confusion and anxiety. These themes were further compared to themes exhibited in Solanaceae studies conducted by Mangialavori (2007) and Sankaran (2002).
165

Assessment of the antibacterial activity of Artemisia afra, Erythrina lysistemon and Psidium guajava

Nsele, Nhlanhla Wiseman 13 November 2013 (has links)
Dissertation submitted in fulfilment for the requirements of the Degree of Master of Technology in Biomedical Technology, Durban University of Technology, 2012. / Introduction Medicinal plants have been used for centuries as remedies for human diseases because they contain components of therapeutic value. Recently, the acceptance of traditional medicine as an alternative form of health care and the development of microbial resistance to the available antibiotics have led scientists to investigate the antimicrobial activity of medicinal plants Aim The aim of this study was to investigate the antimicrobial activity of extracts obtained from medicinal plants used in traditional medicine. A comparative study was carried out on the antimicrobial properties of extracts obtained by two different methods in order to choose that which extracts the most effective antimicrobial compounds. Methodology The plants used in this study Artemisia afra, Erythrina lysistemon and Psidium guajava were harvested from the Silverglen Nature Reserve (Chatsworth) early in the morning (8 a.m.). The leaves of A. afra and P. guajava extracts and the bark of E. Lysistemon were used to prepare the extracts. All plant extracts were prepared according to modified method of the German Homeopathic Pharmacopoea. Two solvents, water and 60 percent ethanol were used to extract the antibacterial compounds from plant material. The extracts were then assessed for their antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The effect of the plant extracts on these bacteria was determined by the disk diffusion test, which was used as the screening test. Positive results were further subjected to the minimum inhibitory concentration and minimum bactericidal concentration assays. Tubes that showed no turbidity were then sub-cultured onto non-selective plates. Bacterial sensitivity testing was carried out in accordance with modified Kirby-Bauer Antimicrobial Sensitivity Test. An attempt was made to identify some antibacterial compounds using Thin Layer Chromatography and High Pressure Liquid Chromatography. Results None of the gram negative organisms were inhibited by Artemisia afra, Erythrina cafra and Psidium guajava. Only the ethanol extracts of all three plants were able to inhibit Staphylococcus aureus but not Escherichia coli and Pseudomonas auruginosa. None of the test organisms were inhibited by the aqueous extracts of all three plants used in this study. In the screening test, the zones of inhibition for ethanol extracts against Staphylococcus aureus ranged from 3mm – 7mm. The minimum inhibitory concentration ranged from 16.67 percent – 83.3 percent inhibition depending on the dilution of the extract. Quercetin and Catechin were identified as some of the antibacterial compounds present in the leaves of Psidium guajava. These two compounds were not identified on Erythrina lysistemon and Artemisia afra. Conclusion The results obtained in this study have proven that Artemisia afra, Erythrina cafra and Psidium guajava ethanol extracts contain antibacterial substances. The ethanol extracts of all plants in this study inhibited the growth of Staphylococcus aureus but had no effect on the gram negative bacteria. Aqueous plant did not inhibit the growth of any bacteria in this study. This study has also shown that antibacterial effect of these extracts may be considerably enhanced in traditional treatment if traditional healers can include ethanol as one of the extraction solvents. The results obtained in this study might be considered sufficient for further studies aimed at isolating and identifying the active compounds and evaluating possible synergism of antimicrobial activity among these extracts. Investigations on toxicity of these extracts should also be carried out.
166

Cross-commodity Guidelines for Neonicotinoid Insecticides in Arizona

Palumbo, John C., Ellsworth, Peter C., Dennehy, Timothy J. 05 1900 (has links)
4 pp. / Arizona enjoys a sustained recovery from the devastating whitefly outbreaks of the early 1990's. This success is built on an IPM strategy that includes the use of selective and effective chemistry. Admire has been a key soil insecticide protecting vegetables and produce throughout Arizona and is the first member of a burgeoning class of chemistry known as the neonicotinoids. New members of this valuable, reduced-risk, class of chemistry are now available to agricultural producers, placing a burden on users of these compounds to adopt rational plans for sustaining their efficacy. This consensus document represents our best guess efforts to limit and share this chemistry among different agricultural interests. Our goal is to preserve the long-term efficacy of the neonicotinoids and protect growers' interests in sustainable and economical whitefly management. Through identification of crop communities (i.e., "multi-crop", "cotton-intensive", and "cotton/melon") common to Arizona agriculture, we have sculpted sensible plans of use that should allow access to this valuable chemistry for everyone, while protecting it from resistance.
167

Effect of Messenger® on Cantaloupe Growth Pattern and Yield

Zerkoune, Mohammed A. 08 1900 (has links)
An experimental site was selected at Yuma Agricultural Research Center, University of Arizona, to evaluate the effect of Messenger on melon plant growth and yield. Four treatments in completely randomized block design replicated four times were applied to melon planted on 84- inch beds. High Mark open pollinated melon variety was planted on 3-20-2001 using a commercial planter. Treatments included Messenger applied at 3-leaf stage on 5-4-2001 Messenger applied every 14 days starting on 5-15, 5-29, 6-13, 6-27-2001, standard management practices and control. Observations collected included plant mapping and yield. Results were variable, showed no significant effect of Messenger on plant growth and yield. However, there was indication that Messenger may have an effect on plant growth pattern and yield. Messenger applied at 3-leaf stage and repeated applications seemed to induce an early melon formation, increased number of nodes and yield. It was not possible to make recommendation based on one-year results. Further investigation is needed to verify the results obtained from this experiment.
168

Messenger® Effect on Melons

Umeda, Kai 08 1900 (has links)
Messenger applied at three timely applications at early runner, bloom, and fruiting stages of watermelon versus bi-weekly applications, showed no significant statistical differences for vine length, number of blooms, or harvestable yields. Visual observations for the watermelon plant health at the end of the season tended to indicate that the three timely applications resulted in slightly more vigorous plants than the bi-weekly treated watermelon plants. Cantaloupe vine growth, number of fruit set, yield weight, and fruit size were not different between Messenger treatments and were not enhanced compared to the untreated check.
169

2001 Yield Response of Processing Onions in the Palo Verde Valley Treated with AuxiGro® WP

Rethwisch, Michael D. 08 1900 (has links)
Processing onions were treated with AuxiGro in spring 2001. Applications were applied at four and 7.5 weeks prior to harvest. A single application of 4 oz. product/acre at either four or 7.5 weeks prior to harvest increased yield by approximately 0.7 tons/acre. Two applications resulted in a 1.3 tons/acre yield increase. Differences noted were not statistically different, but the two application treatment provided an increased net return of approximately $95/acre.
170

Effect of Dry Seed+ Application at Planting 1998 on Processing Onion Yields

Rethwisch, Michael D., Poole, Charles, Poole, Rick, Pacheco, Rudy 08 1900 (has links)
Dry Seed+, a fertilizer/plant growth regulator, was applied to processing onions at planting in the fall of 1998 to evaluate the effect on yields. Yield data obtained June 1999 indicated no effect in this experiment, although this was dissimilar to other trial results. Salt content at the field was thought to have limited yields, and have stressed growing plants, which may have contributed to lack of yield differences noted. Further testing is necessary to further evaluate this product.

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