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Food Agency and Health HabitsBarker, Katelyn Ann 26 May 2021 (has links)
High ultra-processed food (UPF) consumption is associated with weight gain, obesity, metabolic syndrome, cardiovascular disease, all-cause mortality, and type 2 diabetes. "Food agency" refers to an individual's food preparation attitudes and capabilities within a given social and physical food environment. Although there is an association between the ability to prepare certain dishes and higher cooking frequency with lower UPF intake, it is still unclear if cooking and food agency influences UPF consumption due to the lack of research in this area. To date, studies of food agency have not included detailed dietary analyses. This cross-sectional study included 40 adults (73% female, aged 39±15 years, body mass index [BMI] 25.8±4.9 kg/m2) and aimed to determine the relationship between food agency and UPF intake. Food agency scores were calculated using the validated Cooking and Food Provisioning Action Scale (CAFPAS). Cooking behaviors and frequency were also collected. Dietary intake was assessed using three 24-hour dietary recalls with each item categorized by degree of processing using the NOVA classification system. Analyses included one-way ANOVAs between CAFPAS score quartiles [Q] and Pearson correlations between CAFPAS, cooking behaviors, and dietary intake. UPF intake was calculated in percent total calories and percent total grams to account for artificial sweeteners and other low calorie products that may be classified as UPFs. Low food agency was associated with a 14% higher UPF intake (% total calories) compared to high food agency (P=0.03). There were no differences between CAFPAS quartiles and UPF intake in % total grams. When age was divided into three categories, UPF intake was significantly lower in older adults (60+ years) compared to adults aged 19-39 years and 40-59 years by 26.4% and 29.1% respectively (P=0.02). When analyzed using bivariate analysis, lunch (r=-0.482, P=0.002) and dinner (r=-0.385, P=0.014) cooking frequency, frequency of cooking a meal from scratch or fresh ingredients (r=-0.320, P=0.044), and CAFPAS self-efficacy (r= -0.369; P= .019) were negatively correlated with UPF intake (% total kcal). These findings provide support for the possibility of reducing UPF intake through cooking interventions aimed at improving components of food agency such as problem solving, skills to create a meal from what is available, and cooking confidence. Future studies should include a larger, heterogeneous population to provide more insight into dietary differences between levels of food agency and expand the diversity of research in this area. / Master of Science / High ultra-processed food (UPF) consumption is linked to weight gain, obesity, metabolic syndrome, cardiovascular disease, all-cause mortality, and type 2 diabetes. "Food agency" refers to an individual's food preparation attitudes and capabilities within a given social and physical food environment. Although there is a link between the ability to prepare certain dishes and higher cooking frequency with lower UPF intake, it is still unclear if cooking and food agency influences UPF consumption due to the lack of research in this area. To date, studies of food agency have not included detailed dietary analyses. This study aimed to determine the relationship between food agency and UPF intake. Food agency scores were calculated using the validated Cooking and Food Provisioning Action Scale (CAFPAS). Cooking frequency and behaviors were also collected. Dietary intake was assessed using three 24-hour dietary recalls with each item categorized by degree of processing using the NOVA classification system. Participants with low food agency had higher UPF intake in percent total calories compared to those with high food agency. There were no differences between food agency and UPF intake in percent total grams. Adults aged 60 and over consumed less UPF compared to adults below the age of 60. Participants with higher food agency were more likely to make a meal from scratch or fresh ingredients. As frequency of cooking a meal from scratch or fresh ingredients, cooking dinner or lunch increased, and CAFPAS self-efficacy scores increased percent total calories from UPFs decreased. These findings provide support for the possibility of reducing UPF intake through cooking interventions aimed at improving components of food agency such as problem solving, skills to create a meal from what is available, and cooking confidence. Future studies should include a larger, heterogeneous population to provide more insight into dietary differences between levels of food agency and expand the diversity of research in this area.
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Acceleration of Reverse Intersystem Crossing in Purely Organic Emitters and its Application to Hyperfluorescence Systems / 純有機発光材料における逆項間交差の高速化とHyperfluorescence系への応用Ren, Yongxia 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24903号 / 工博第5183号 / 新制||工||1989(附属図書館) / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 梶 弘典, 教授 関 修平, 教授 寺村 謙太郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Enhancing K-12 School-Based Food and Nutrition Education: Developing and Validating a Socioecological Theoretical Framework and Practical Program Evaluation ToolGreaves-Peters, Natalie January 2024 (has links)
Introduction: This dissertation investigates the critical components of school-based food and nutrition education (SBFNE) programs aimed at enhancing their impact on students’ dietary behaviors. Over the past century, significant shifts in the food landscape have altered dietary habits, with a rise in ultra-processed food (UPF) consumption and a decline in fruit and vegetable intake, particularly among children. This trend underscores the importance of SBFNE programs, which, akin to STEAM subjects, are vital for public health. Schools, where children spend much of their time, are ideal settings for implementing comprehensive, research-based SBFNE programs to reconnect students with healthy food sources and promote better eating habits.
Research Questions: This three-paper dissertation addresses several key research questions:
1. What educational and programmatic components contribute to effective SBFNE programs?
2. How can these components be synthesized into a comprehensive theoretical framework and practical program evaluation tool?
3. What insights and recommendations can be gathered from a formative evaluation of these tools?
Chapter 2 (Article 1): Objective: Identify educational and programmatic components from the research literature that make SBFNE effective in fostering positive dietary behavior among K-12 students. Methodology: An umbrella review of peer-reviewed literature reviews and government reviews on the effectiveness of SBFNE. All included reviews were assessed for methodological quality. Data Analysis: For each included review, a list was made of the components that contribute to the effectiveness of SBFNE to change dietary behavior. These components were compared across reviews. A final list of components contributing to effectiveness of SBFBE was created with their prevalence in the included reviews indicating whether the impact on effectiveness of SBFNE was positive, mixed or not assessed.
Key Findings: This umbrella review identified 20 critical components essential for effective SBFNE programs from 44 reviews, encompassing 1,115 unique primary studies conducted between 1900 and 2022. These components, such as cultural inclusivity and connections to school meals, were integrated into a structured theoretical framework based on the Socioecological Model (SEM) with the components mapped to the first four of six SEM levels: individual, interpersonal, community, and organizational. Conclusions: This study is the first to identify and map research-based critical components into an SEM framework, that influence behaviors and outcomes and can be used to further SBFNE research.
Chapter 3 (Article 2): Objective: Develop and pilot test a SBFNE program evaluation tool derived from 20 critical components that were integrated into an SEM framework. Methodology: The tool, developed in Google Sheets, employed a 0-3 scoring system to evaluate the integration of each component with an accompanying detailed rating guide. The pilot test involved component ranking exercises, concept mapping, and curriculum lesson reviews with SBFNE program developers (n=3). Data Analysis: Insights from the pilot test led to significant refinements in the tool and data collection protocol.
Key Findings: Participants found the ranking exercise uncomfortable due to component interdependencies. They found the concept mapping exercise engaging and intuitive. The program developers found the curriculum review to be tedious and insufficient with only one lesson reviewed, but they thought this type of program review provided valuable guidance for revising and improving SBFNE programs. The interviews were long, usually more than two hours, and transcription was time-consuming. Conclusions: The pilot provided data to refine the program evaluation tool and to refine the data collection protocol for a formative evaluation of the program evaluation tool.
Chapter 4 (Article 3): Objective: Conduct a formative, mixed-methods evaluation to refine the integrated SEM and program evaluation tool for SBFNE programs. Methodology: Recruited SBFNE program developers (n=9) who participated in an exercise to categorize 20 critical components for effectiveness of SBFNE, created a concept map on how the 20 components interact, underwent a program review in which programs were scored 0–3 for the 20 components, received recommendations for program improvement for components that scored less than a three, decided on which recommendations they would enact, and provided feedback on the experience. Data Analysis: Descriptive statistics and thematic analysis identified patterns and insights from qualitative responses, leading to revisions in the evaluation tool and a new practice-based tool.
Key Findings: For the categorization exercise there was a range of agreement between program developers and the literature on the critical nature of the SBFNE components, with each of the nine participants rating between four and 17 out of the 20 components as essential. The concept maps the program developers created represented the interconnectedness of the components and led to the development of a practice-based logic model. The program review process showed that programs can be scored on how they are using the components, recommendations can be made for components that did not score a three, and program developers can implement the recommendations. The feedback process indicated that program developers found the activities they did for this research useful for refining and improving their programs, to make them more effective at dietary behavior change. Conclusions: The program evaluation tool and new practice-based model showed promise to be used in future research on SBFNE.
Conclusions: This dissertation establishes a robust foundation for SBFNE, integrating critical educational and programmatic components with innovative evaluation tools. The integrated SEM and practical program evaluation tools can improve the quality of SBFNE programs, which can help to foster positive dietary behavior change among K-12 students, addressing the rise in UPF consumption and decline in fruit and vegetable intake. This research lays the groundwork for future initiatives aimed at nurturing healthier, informed, and empowered generations.
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Uso de película comestível, cloreto de cálcio e ácido ascórbico para a conservação do melão \'Amarelo\' minimamente processado / Application of edible coating, calcium chloride and ascorbic acid for conservation of minimally processed melonMiguel, Ana Carolina Almeida 21 February 2008 (has links)
Este trabalho teve como objetivo avaliar o efeito da utilização de película comestível, ácido ascórbico e cloreto de cálcio sobre a conservação do melão \'Amarelo\' minimamente processado. Primeiramente, visando à obtenção de um produto conveniente foram estudados os aspectos microbiológicos e os efeitos dos tratamentos sobre a taxa respiratória e a produção de etileno de produtos de melão durante o armazenamento refrigerado. Os frutos depois de selecionados, lavados e higienizados em solução de dicloroisocianurato de sódio dihidratado (200ppm) tiveram a polpa cortada em cubos (3cm de aresta), que foi imersa em solução de dicloroisocianurato de sódio dihidratado (100ppm) e drenada. A seguir, foram divididos em 4 lotes, cujos cubos foram imersos nas soluções de cloreto de cálcio a 1%, ácido ascórbico a 1% e película a base de alginato (1%) e um lote foi deixado sem tratamento, o qual serviu de testemunha. Após a segunda drenagem, os melões tratados foram acondicionados em bandejas de tereftalato de polietileno (PET) e armazenados a 5°C. Verificou-se que, em todos os tratamentos, houve redução da taxa respiratória ao longo do período de armazenamento e foi detectada baixa produção de etileno. Quanto à qualidade microbiológica, as contagens de bactérias psicrotróficas e de bolores e leveduras mantiveram-se dentro dos limites aceitáveis. Não foi detectada a presença de microrganismos do grupo coliformes e de Salmonella, mostrando que o processamento foi realizado de forma adequada. No segundo experimento estudou-se o efeito dos tratamentos químicos quanto à manutenção dos parâmetros físicos e químicos dos melões \'Amarelo\' minimamente processados. Verificou-se perda de massa de 0,34% durante todo o período de armazenamento. O ácido ascórbico fornecido pelo tratamento levou a um aumento na acidez nos frutos. O uso de película a base de alginato de sódio resultou em melões com menores teores de sólidos solúveis e de acidez titulável, menores pH e grau de solubilização da pectina, melhor sabor, além de coloração mais escura da polpa, em decorrência da cor da solução filmogênica. Os tratamentos químicos estudados pouco afetaram as características físicas e químicas dos produtos de melão e não estenderam a sua vida útil. No terceiro experimento avaliou-se a manutenção da qualidade sensorial, utilizando provadores treinados, através do método da Análise Descritiva Quantitativa (ADQ), bem como a aceitação do produto pelo consumidor. A ADQ mostrou que os tratamentos testados não apresentaram efeito no prolongamento da vida útil dos melões \'Amarelo\' minimamente processados. O teste de consumidor indicou que os melões tratados com cloreto de cálcio e com ácido ascórbico foram os melhor aceitos pelos provadores e revelou que não houve diferença quanto à intenção de compra. No quarto experimento estudaram-se alternativas para o aproveitamento das cascas e das sobras de polpa de melões minimamente processados. Da casca foram desenvolvidos três produtos, compota, doce e glaceado; e com as sobras de polpa foram elaboradas geléias. O teste sensorial indicou que todos os produtos elaborados, com exceção do doce de melão, obtiveram boa aceitabilidade por parte dos julgadores, com índice de aceitabilidade acima de 80%. / This work aims to evaluate the effect of the use of edible film, ascorbic acid and calcium chloride on the conservation of minimally processed melon. In order to obtain a convenient product, the microbiological aspects have been studied in order to evaluate the effect of the treatments on the respiratory rate and ethylene production of melons during the refrigerated storage. The fruits were selected, washed and sanitized in sodium dichloroisocianurate dehydrated solution (200ppm). The pulp of the fruits was cut in cubes (3cm of edge), immersed in sodium dichloroisocianurate dehydrated solution (100ppm) and drained and consequently it was divided in four lots. These cubes were immersed in calcium chloride (1%), ascorbic acid (1%) and alginate film (1%) and a lot was left without any treatment, which served as control. After the second drainage, the melons were placed in trays of polyethylene terephtalate (PET) and stored at 5°C. It has been verified that in all the treatments there was a reduction of the respiratory rate during the storage and the low ethylene production was detected. Concerning the microbiological quality, psychotropic bacteria, molds and yeasts counts were within acceptable limits and fecal bacteria group and Salmonella were not detected which demonstrates that the processing was carried out adequately. The second experiment was studied in order to evaluate the effect of the chemical treatments on the maintenance of the physical and chemical parameters of minimally processed melons. It was verified that the loss of mass was 0.34% during the storage. The ascorbic acid supplied for the treatment suffered an increase of acidity of fruits. The edible coating of sodium alginate resulted in melons with fewer contents of soluble solids and titratable acidity, lesser pH and degree of pectin solubilization, better flavor, and pulp with darker coloration, which results the color of the film solution. It was concluded that the chemical treatments affected the physical and chemical characteristics of minimally processed melons a little and they did not extend the product\'s shelf-life. In the third experiment, the maintenance of the sensorial quality, using trained panelists, through the Quantitative Descriptive Analysis Method (QDA), as well as the acceptance of the product for the consumer has been evaluated. The QDA showed that the treatments were not presented to be effective in the prolongation of the shelf-life of minimally processed melons. The consumer test indicated that the melons treated with calcium chloride and ascorbic acid were more accepted by the panelists and showed that there was no significant difference about buying intention. The fourth experiment was intended to study alternatives for the exploitation of the peels and the pulp\'s leftovers of minimally processed melons. With the peels, three products were developed: compote, candy, icing candy and jellies were made with the leftovers of the pulp. The sensorial test indicated that all the elaborated products, except for the candy made of melon peel, showed good acceptability for panelists, with rate of acceptability above of 80%.
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Otimização da vida útil da tilápia cultivada (Oreochromis niloticus), minimamente processada e armazenada sob refrigeração. / Optimizing the shelf-life of minimally processed aquacultured tilapia (Oreochromis niloticus) stored under refrigeration.Soccol, Marcilene Camilo Heidmann 26 February 2003 (has links)
A efetiva consolidação da piscicultura depende do escoamento da produção, que por sua vez depende da demanda. Para que o consumo de pescado no Brasil seja ampliado, é necessário que haja oferta de produtos com a qualidade exigida pelo consumidor. Esta pesquisa teve como objetivo a obtenção de um novo produto, tipo alimento de conveniência - tilápia minimamente processada, estabelecendo a vida útil deste, por monitoramento dos componentes físico-químicos e avaliação sensorial e microbiológica. Foram utilizados peixes provenientes de áreas de cultivo do Estado de São Paulo, da região de Jaú, da espécie tilápia do Nilo, Oreochromis niloticus, os quais foram submetidos à depuração, eviscerados, filetados, acondicionados em bandejas de poliestireno e recobertos com filmes plásticos de etileno-álcool-vinílico - EVOH (controle); também foi feito o embalamento sob atmosfera modificada - EAM (60%CO2+40%O2) e a vácuo. Parte dos peixes foi submetida ao tratamento químico, por imersão em ácido acético a 1%. As amostras embaladas foram mantidas sob refrigeração, na faixa de 1 ± 1 o C, quando foram submetidas às análises, no 1 o dia de experimento e aos 7, 13 e 20 dias de armazenamento refrigerado. Os tratamentos aplicados não apresentaram diferenças significativas para composição centesimal, nitrogênio não protéico - NNP, bases nitrogenadas voláteis totais - BNVT e pH. A EAM associada ou não ao ácido acético apresentou valores mais elevados de TBA (ácido tiobarbitúrico), sendo detectada a presença de ranço pelos provadores, integrantes da equipe de análise sensorial. Os filés tratados com ácido acético apresentaram-se descoloridos e com textura menos firme, em relação aos demais tratamentos. Durante o período de armazenamento não detectou-se a presença de Salmonella, Clostridium sulfito-redutores e E. coli. Os tratamentos embalados em EAM e a vácuo, associados ou não ao ácido acético, inibiram o desenvolvimento de S. aureus, coliformes totais e psicrotróficos proporcionando uma vida útil de 20 dias. O embalamento a vácuo associado ao ácido acético foi o tratamento que manteve as características físico-químicas, microbiológicas e sensoriais mais estáveis até o término do experimento. / The effective aquaculture consolidation depends on the production sale, which in the other hand, depends on the demand. In order to increase Brazilian fish consumption, it is necessary to offer products with quality demanded by the consumers. The purpose of this research was to obtain a new convenience product - minimally processed tilapia. The shelf-life of the product were determining by monitoring physical-chemical components, sensory and microbiological analysis. With this intent, aquacultured Nile tilapia (Oreochromis niloticus) raised in farms located in the Jau region, Sao Paulo State, was depurated, gutted, filleted, packed in polyestirene trays and covered with ethylene-vinyl-alcohol (EVOH) plastic films (control). It was also made packing with modified atmosphere (MAP) 60%CO2+40%O2 and vacuum packing. Part of the fish was chemically treated by immersing in a 1% acetic acid solution. The packed samples were storage under a temperature which ranged from 1 ± 1 oC and had been analyzed at the 1st day of experiment and to the 7th , 13th and 20th days. No significant differences were verified among treatments for the centesimal composition, non-protein nitrogen (NPN), total volatile bases nitrogen (TVBN) and pH as well. The use of the MAP, whether associated with acetic acid or not, promoted the TBA (thiobarbituric acid) increasing. It was detected rancidity the team responsible for the sensory evaluation. The fillets treated with acetic acid were fainted colors and showed less firm texture, when compared to the non-treated ones. Salmonella, Clostridium sulfite-reducing and E. coli were not detected during the storage period. Treatments using MAP and vacuum packing, whether associated with acetic acid or not, inhibited the development of S. aureus, total coliforms and psychrotrophic, maintaining the shelf life to 20 days. However, the treatment combining vacuum packing and acetic acid maintained the physical-chemical, microbiological and sensory characteristics stabler until the end of the experiment.
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Respostas fisiológicas e bioquímicas de diferentes cultivares de batatas ao processamento mínimo / Physiological and biochemical responses of different potato cultivars to minimal processingVitti, Maria Carolina Dário 28 August 2007 (has links)
O presente trabalho teve como objetivo avaliar aspectos fisiológicos e bioquímicos de batatas cv. Ágata, Asterix e Monalisa minimamente processadas. Primeiramente foram estudadas variáveis fisiológicas e microbiológicas de batatas armazenadas a 5, 15 e 25ºC. As batatas \'Asterix\' apresentaram as maiores taxas respiratórias em relação a \'Ágata\' e \'Monalisa\', independente da temperatura de armazenamento. As contagens de bactérias psicrotróficas e coliformes totais, para todas as cultivares armazenadas a 5oC durante 9 dias de armazenamento, mantiveram-se dentro dos padrões aceitáveis. O armazenamento a 5oC foi eficiente no controle da atividade metabólica e na segurança de batatas minimamente processadas. No segundo experimento, o ensaio enzimático realizado teve como objetivo verificar o efeito de diferentes cultivares e de temperaturas de armazenamento (5 e 15ºC) sobre a atividade das enzimas fenilalanina amônia-liase (PAL), polifenoloxidase (PPO) e peroxidase (POD). As atividades enzimáticas aumentaram para todas as cultivares na temperatura de 15ºC. Batatas \'Ágata\' e \'Asterix\' são mais indicadas para processamento mínimo do que \'Monalisa\', sendo esta mais susceptível ao escurecimento enzimático. O terceiro experimento avaliou os níveis de carboidratos não estruturais em batatas minimamente processadas e armazenadas a 5 e 15ºC. A maior degradação de amido em batatas \'Asterix\' armazenadas a 5ºC esteve relacionada com o aumento do teor de açúcares solúveis verificado para este tratamento. Foi observado um aumento nos teores de amido para a cultivar \'Ágata\' armazenada a 5ºC. Os teores de sacarose decresceram para todas as cultivares armazenadas a 5ºC e houve manutenção nos teores deste carboidrato quando armazenadas a 15ºC. No quarto experimento foram testadas diferentes combinações de antioxidantes nas três cultivares armazenadas a 5ºC. Batatas \'Monalisa\' apresentaram os maiores teores de fenóis totais e valores de atividade da PAL, POD e PPO independente do tratamento. Batatas \'Ágata\' tratadas com ácido ascórbico 2% + cisteína 0,5% e cisteína 0,5% + 4-hexilresorcinol 0,01% apresentaram os menores valores de atividade da PAL, POD e PPO. Para as cultivares Asterix e Monalisa os melhores resultados obtidos foram nas combinações com 4-hexilresorcinol e cisteína, respectivamente. / The purpose of the present work was to evaluate physiological and biochemical aspects of minimally processed Agata, Asterix and Monalisa potato cultivars. First physiological and microbiological variables of fresh-cut potatoes stored at 5, 15 and 25ºC were evaluated. Potatoes \'Asterix\' showed the highest respiratory rates when compared to potatoes cv. Agata and Monalisa, regardless of the storage temperature. Psychrotrophic bacteria and total coliforms counts were within acceptable limits for all cultivars stored at 5oC during 9 days of storage. Storage at 5oC was effective to control the metabolic activity and to keep food safety of minimally processed potatoes. In a second experiment, the effect of different cultivars and storage temperatures (5 and 15ºC) on the enzymatic activity of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD) was studied. Enzymatic activity increased in all cultivars at 15ºC. \'Agata\' and \'Asterix\' potatoes were more suitable for minimal processing than \'Monalisa\'. This last cultivar is more susceptible to enzimatic browning. The third experiment was aimed at evaluating non-structural carbohydrates levels in mimally processed potatoes stored at 5 and 15ºC. The highest starch degradation rate was observed in potatoes \'Asterix\' stored at 5ºC, which was related to the increase in the soluble sugar amount verified in this experiment. There was an increase in starch content in \'Agata\' potatoes stored at 5ºC. Sucrose contents decreased in all cultivars stored at 5ºC and remained constant in cultivars stored at 15ºC. In a fourth experiment, different combinations of antioxidants in the three potato cultivars stored at 5ºC were studied. Potatoes \'Monalisa\' showed the highest total phenol amounts and the highest activities of PAL, PPO and POD, regardless of treatment. \'Agata\' potatoes treated with ascorbic acid 2% + cysteine 0.5% and cysteine 0.5% + 4-hexylresorcinol 0.01% showed the lowest valves activities of PAL, POD and PPO. For the Asterix and Monalisa cultivars, the best results were obtained when combinations of 4-hexylresorcinol and cysteine were used, respectively.
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Capim Xaraés sob pastejo: respostas agronômicas e morfofisiológicas, e adaptação do modelo CROPGRO para a predição de crescimento / Xaraés palisadegrass under grazing: agronomic, morphological, and physiological responses, and adapting the CROPGRO model for predicting forage growthPedreira, Bruno Carneiro e 02 September 2009 (has links)
Para otimizar o sistema de produção animal, trabalhando com modelos, é necessário o conhecimento de aspectos morfofisiológicos das plantas forrageiras e, para isso, é preciso compreender os efeitos da ação do animal envolvidos na rebrotação das plantas e, conseqüentemente, na sua produção. O objetivo deste trabalho foi avaliar as respostas agronômicas e morfofisiológicas, e adaptar o modelo CROPGRO para predizer o crescimento de capim Xaraés submetido a estratégias de pastejo intermitente, com freqüências de desfolhação baseadas em interceptação luminosa ou calendário, visando estabelecer uma base racional de manejo e observando o sistema sob o ponto de vista fisiológico da planta. O estudo foi realizado na Escola Superior de Agricultura \"Luiz de Queiroz\", campus da USP localizado em Piracicaba - SP, numa área de Nitossolo Vermelho Eutroférrico, estabelecida com capim Brachiaria brizantha cv. Xaraés, onde foram avaliadas as características agronômicas, morfológicas e fisiológicas deste, tais como produção de forragem, índice de área foliar (IAF), interceptação luminosa (IL). O delineamento experimental foi inteiramente casualizado com três tratamentos e três repetições, totalizando nove unidades experimentais (piquetes) de 120 m² cada, as quais foram pastejadas por grupos de animais sempre que a IL do dossel chegasse a 95%, ou a 100% ou a cada 28 dias. As estratégias de pastejo apresentaram diferentes acúmulos totais de forragem durante o verão. A estratégia 100% de IL, devido à sua menor freqüência, garantiu à comunidade vegetal um maior intervalo de desfolhações e, conseqüentemente, maior período de crescimento. No primeiro ano não houve diferença entre estratégias no total acumulado, mas as estratégias 28-d e 100% IL reduziram o total de forragem acumulada no segundo ano. A dinâmica do acúmulo apresentou padrões distintos para os componentes morfológicos: folhas, colmo e material morto, assim como respostas diferentes à estrutura e produção de forragem. Os menores estoque de nitrogênio e carboidratos não-estruturais nas raízes sugerem o efeito negativo dos longos períodos de crescimento impostos pelas estratégias 100% IL e 28-d. Sob estratégia de pastejo intermitente, sugere-se que o capim Xaraés seja manejado respeitando-se 30 cm como altura de entrada e 15 cm como pós-pastejo, preterindo o acúmulo de colmos. O resultado da adaptação sugere que o modelo CROPGRO é uma ferramenta eficiente para integrar aspectos fisiológicos de B. brizantha e pode ser usado para simular com boa acurácia. / On optimization of the animal production systems using models, morphological and physiological aspects of forage plants is required. Moreover, is necessary to understand grazing effects on regrowth, and consequently, on forage mass accumulation. The objective of this research was to evaluate the morphological and physiological responses, and adapting the CROPGRO model for predicting forage growth, in pastures under intermittent grazing, where defoliation frequency was dictated either by levels of light interception or by chronological time, in order to try to rationalize management practices under a physiological standpoint. The study was conducted at Escola Superior de Agricultura \"Luiz de Queiroz\", USP campus in Piracicaba, SP, on a kandiudalfic euthrudox using a one-year-old pasture of Xaraés palisadegrass where agronomic, morphological and physiological traits, such as forage yield, leaf area index (LAI) and light interception (LI) were studied. The experimental design was completely randomized with three treatments and three replications, for a total of nine experimental units (paddocks) of 120 m² each, which were mob grazed whenever canopy light interception reached 95% or 100%, or every 28 days. Grazing strategies resulted in different seasonal forage yields. On the first year, total mass accumulation was similar among strategies, but 28-d and 100% LI strategies reduced this amount on the second year. The herbage accumulation during the regrowth presented different patterns on each morphological component: leaf, stem and dead material, as well as, different responses on structure and forage production. Lower nitrogen and total non-structural carbohydrates pools on roots suggest a negative effect caused by longer rest periods on 100% LI and 28-d strategies. The results suggesting that Xaraes palisadegrass under intermittent grazing stocking be management respecting 30 cm as pre-grazed and 15 cm as stubble height, avoiding stem accumulation. The adaptation result shows that CROPGRO is an efficient tool to integrate physiological aspects of B. brizantha and can be used to simulate with good accuracy.
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Avaliação da segurança microbiológica de hortaliças minimamente processadas, pela enumeração de microrganismos indicadores, Salmonella sp. e Listeria monocytogenes por métodos convencionais e aplicação da PCR em tempo real na quantificação de Listeria monocytogenes / Evaluation of the microbiological safety of minimally processed vegetables by the enumeration of indicative microorganisms, Salmonella spp. and Listeria monocytogenes by conventional methods and quantification of Listeria monocytogenes by real-time PCROliveira, Maria Aparecida de 22 December 2008 (has links)
A vida moderna tem gerado mudanças importantes nos hábitos alimentares em todo o mundo e observa-se um aumento da demanda por alimentos prontos para o consumo, tais como frutas e hortaliças minimamente processadas. As condições de embalagem e armazenamento destes produtos podem favorecer a multiplicação de bactérias psicrotróficas, destacando-se o patógeno Listeria monocytogenes. Para estudos de avaliação de riscos microbiológicos relativos a L. monocytogenes, dados quantitativos são fundamentais, mas, os métodos para enumeração disponíveis atualmente são trabalhosos e morosos. Há grande interesse no desenvolvimento de métodos rápidos para a determinação das populações de L. monocytogenes, o que pode reduzir significativamente o tempo de análise. Neste trabalho, foram analisadas 162 amostras de hortaliças minimamente processadas adquiridas no comércio varejista de Ribeirão Preto/SP, no período de setembro de 2007 a agosto de 2008. Foram realizados ensaios convencionais para enumeração de coliformes totais e termotolerantes, Escherichia coli e bactérias aeróbias psicrotróficas. Foi realizada a detecção de Listeria sp. por imunoensaio (Oxoid Listeria Rapid Test) e de Salmonella por método convencional. Alíquotas congeladas de amostras positivas para L. monocytogenes e Salmonella sp. foram também avaliadas quantitativamente empregando-se métodos convencionais. Para quantificação de L. monocytogenes foi utilizado o método da Reação de Polimerase em Cadeia (PCR) em tempo real, com primers de DNA baseados em 16S rRNA. Para a comparação do método de PCR em tempo real e método convencional de cultivo, foram inoculadas seis amostras de hortaliças minimamente processadas (alface, cheiro-verde, couve, almeirão, repolho e acelga) com três níveis de inoculação. Dentre as 162 amostras de hortaliças analisadas, L. monocytogenes foi detectada em uma amostra de couve e uma de cheiro-verde, com populações de 1,5 x 103 e 0,43 NMP/g, respectivamente. Salmonella sp. foi isolada de duas amostras de almeirão, com populações de 0,09 e 4,6 NMP/g. Contaminação por coliformes totais foi detectada em 132 (81,5%) amostras e por coliformes termotolerantes em 107 (66%) amostras. Escherichia coli foi confirmada em 86 (53,1%) amostras, enquanto que 158 (96,7%) amostras apresentaram população de bactérias psicrotróficas maior que 5 log UFC/g. Os resultados obtidos entre os dois métodos desenvolvidos apresentaram pouca variação e todos os resultados foram concordantes considerando-se o intervalo de confiança de 95% da técnica do NMP (SWANSON; PETRAN; HANLIN, 2001). A PCR em tempo real foi otimizada com a preparação comercial ABSOLUTETM QPCR SYBR® Green Mix (ABgene, Reino Unido) e os primers utilizados mostraram ser específicos para L. monocytogenes. As populações de microrganismos encontradas nestes alimentos indicaram a baixa qualidade microbiológica e evidenciaram a importância da implantação de programas para garantia da inocuidade de alimentos na cadeia produtiva das hortaliças minimamente processadas. A PCR em tempo real mostrou ser de fácil execução e diminuiu o tempo de obtenção de resultados para pouco mais que 48 horas em comparação com o tempo gasto (7 dias) quando as hortaliças foram analisadas por meio do método convencional de cultivo. / Modern lifestyles have deeply changed eating habits worldwide, with an increasing demand for ready-to-eat foods, including minimally processed fruits and leafy greens. Packaging and storage conditions of these products may favor the growth of psychrotrophic bacteria, such as the pathogen Listeria monocytogenes. For microbiological risk assessment, it is crucial to generate quantitative data on foodborne pathogens, but the enumeration methods currently available are labor and time consuming. There is great interest in the development of reliable and fast methods for enumeration of L. monocytogenes, in order to shorten the time needed to obtain quantitative results. In this study 162, samples of leafy vegetables minimally processed were acquired at retail market in Ribeirão Preto from September, 2007 to August 2008 and they were analysed by conventional enumerating methods for total and thermophilic coliforms, Escherichia coli and psychrotrophic aerobic bacteria. Presence or absence of Listeria spp. was evaluated by immunoassay (Oxoid Listeria Rapid test) and detection of Salmonella was performed by conventional methods. Frozen aliquots of Salmonella spp. and L. monocytogenes positive samples were quantitatively evaluated by conventional methods and L. monocytogenes was also enumerated by real-time Polymerase Chain Reaction (PCR) with DNA primers based on 16S rRNA. Real-time PCR method was applied to analyze six artificially contaminated vegetables and the results obtained with this methodology were similar to the ones obtained with conventional most probably number (MPN) technique with a confidence interval of 95% (SWANSON; PETRAN; HANLIN, 2001). Of the 162 samples analyzed, L. monocytogenes was detected in one sample of collard green and in one mixed bunch of parsley plus spring onion (1.5x103 and 0.43 MPN/g, respectively). Salmonella sp was detected in two samples of common chicory with populations of 0.09 and 4.6 MPN/g. One hundred and thirty two samples (81.5%) showed contamination by total coliforms and 107 (66%) by thermophilics coliforms. Escherichia coli was confirmed in 86 (53.1%) samples while 156 (96.7%) showed populations of psychrotrophic bacteria above of 5 log CFU/g. PCR was optimized with a commercial preparation ABSOLUTE TM QPCR SYBRÒ Green Mix (ABgene, UK) and the primers utilized were specific for L. monocytogenes. These results showed the low microbiologic quality of minimally processed vegetables samples studied and indicate an urge for implementation of quality programs from producer to processors of these ready-to-eat foods. Realtime In comparison with the conventional culture method, real-time PCR was more easily performed and the time required to obtain the results was reduced to ca. 48 hours, in comparison with 7 days for conventional method.
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Cadeia logística segura brasileira: suprimento internacional de carne bovina industrializada e rastreabilidade. / Brazilian secure supply chain: processed beef supply and traceability.Maria Lídia Rebello Pinho Dias 26 March 2012 (has links)
O presente trabalho de pesquisa modela a cadeia de suprimentos brasileira da carne bovina industrializada destinada ao mercado internacional e aspectos do conjunto normativo incidente sobre este setor. Por meio desta modelagem, são apresentados os requisitos para um sistema de controle e integração das informações em tempo real em frigoríficos exportadores que atenda as exigências do poder público e de parceiros comerciais, além das principais necessidades do próprio frigorífico. Este trabalho de pesquisa apresenta, também, a arquitetura de hardware, de software e a metodologia do sistema operacional proposto, além dos benefícios advindos de sua eventual implementação. Este sistema, ora denominado Cadeia Logística Segura para Exportação de Carne Bovina Industrializada (CLSECB) contém as informações necessárias para a gestão do frigorífico, o controle de qualidade do produto, o trâmite burocrático da mercadoria, através da aplicação de dispositivos de identificação por rádio frequência (RFID) e do sistema operacional proposto. O CLSECB, portanto, permite identificar o produto (individualmente e/ou por lotes), associar informações ao produto (tanto sobre sua qualidade quanto sobre sua procedência), coletar e transmitir essas informações de forma rápida, eficiente e segura. Deste modo, o CLSECB é um sistema que, se implementado, permitirá a rastreabilidade total dentro do processo de industrialização e, será um avanço para a rastreabilidade total ao longo de toda a cadeia de suprimentos da carne bovina industrializada. Tais realizações, por fim, aproximam a cadeia de suprimentos da carne bovina industrializada dos ideais do programa Brasil-ID, do objetivo de obter uma linha azul para a exportação deste produto e do objetivo de expandir os mercados existentes e conquistar novos mercados internacionais. / This research work models the Brazilian supply chain of industrialized beef destined to the international market and regulatory aspects regarding this sector. Through this modeling, the requirements are presented for a system that controls and integrates information in real-time around beef producer exporters that meets the demands of the Government and business partners, including the main needs of the industry itself. This research work also presents the hardware and the software architecture and the methodology of a proposed operating system, including the benefits obtained from its eventual implementation. Thus, the proposed system, called Secure Supply Chain for the Export of Processed Beef (CLSECB Cadeia Logística Segura para Exportação de Carne Bovina Industrializada), contains the necessary information to the management of the industry, the quality control of the product, the bureaucratic processes of goods through the application of Radio-Frequency Identification (RFID) devices and the proposed operation system. The CLSECB allows the identification of the product (individually and/or by sets), the association of the products information (being it by its quality or by its precedence) and the collection and transmission of this information in a fast, efficient and secure way. Summarizing, the CLSECB is a system that, if implemented, will allow full traceability through the whole Brazilian supply chain of industrialized beef to exportation. Such accomplishments, bring together the Brazilian supply chain of industrialized beef and the ideals of the Brazil-ID program, the goal to obtain a blue channel to the exportation of this product and the target to expand existing markets and conquer new international markets.
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Cadeia logística segura brasileira: suprimento internacional de carne bovina industrializada e rastreabilidade. / Brazilian secure supply chain: processed beef supply and traceability.Dias, Maria Lídia Rebello Pinho 26 March 2012 (has links)
O presente trabalho de pesquisa modela a cadeia de suprimentos brasileira da carne bovina industrializada destinada ao mercado internacional e aspectos do conjunto normativo incidente sobre este setor. Por meio desta modelagem, são apresentados os requisitos para um sistema de controle e integração das informações em tempo real em frigoríficos exportadores que atenda as exigências do poder público e de parceiros comerciais, além das principais necessidades do próprio frigorífico. Este trabalho de pesquisa apresenta, também, a arquitetura de hardware, de software e a metodologia do sistema operacional proposto, além dos benefícios advindos de sua eventual implementação. Este sistema, ora denominado Cadeia Logística Segura para Exportação de Carne Bovina Industrializada (CLSECB) contém as informações necessárias para a gestão do frigorífico, o controle de qualidade do produto, o trâmite burocrático da mercadoria, através da aplicação de dispositivos de identificação por rádio frequência (RFID) e do sistema operacional proposto. O CLSECB, portanto, permite identificar o produto (individualmente e/ou por lotes), associar informações ao produto (tanto sobre sua qualidade quanto sobre sua procedência), coletar e transmitir essas informações de forma rápida, eficiente e segura. Deste modo, o CLSECB é um sistema que, se implementado, permitirá a rastreabilidade total dentro do processo de industrialização e, será um avanço para a rastreabilidade total ao longo de toda a cadeia de suprimentos da carne bovina industrializada. Tais realizações, por fim, aproximam a cadeia de suprimentos da carne bovina industrializada dos ideais do programa Brasil-ID, do objetivo de obter uma linha azul para a exportação deste produto e do objetivo de expandir os mercados existentes e conquistar novos mercados internacionais. / This research work models the Brazilian supply chain of industrialized beef destined to the international market and regulatory aspects regarding this sector. Through this modeling, the requirements are presented for a system that controls and integrates information in real-time around beef producer exporters that meets the demands of the Government and business partners, including the main needs of the industry itself. This research work also presents the hardware and the software architecture and the methodology of a proposed operating system, including the benefits obtained from its eventual implementation. Thus, the proposed system, called Secure Supply Chain for the Export of Processed Beef (CLSECB Cadeia Logística Segura para Exportação de Carne Bovina Industrializada), contains the necessary information to the management of the industry, the quality control of the product, the bureaucratic processes of goods through the application of Radio-Frequency Identification (RFID) devices and the proposed operation system. The CLSECB allows the identification of the product (individually and/or by sets), the association of the products information (being it by its quality or by its precedence) and the collection and transmission of this information in a fast, efficient and secure way. Summarizing, the CLSECB is a system that, if implemented, will allow full traceability through the whole Brazilian supply chain of industrialized beef to exportation. Such accomplishments, bring together the Brazilian supply chain of industrialized beef and the ideals of the Brazil-ID program, the goal to obtain a blue channel to the exportation of this product and the target to expand existing markets and conquer new international markets.
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