The overwhelming majority of plant species introduced into a new range never become invasive. Consequently, identification of factors allowing the small fraction of successful invaders to naturalize, increase in abundance, and displace resident species continues to be a key area of research in invasion biology. Of the considerable number of hypotheses that have been proposed to resolve why some plant species become noxious pests, the enemy release hypothesis (ERH) is one of the most commonly cited. The ERH maintains that invasive plants succeed in a new range because they are no longer regulated by their coevolved natural enemies, and this reduction in enemy pressure imparts a competitive advantage over native species, which continue to be negatively impacted by top-down processes. Alternatively, the ability of invasive plant species to outperform their counterparts, rather than escape from enemies, may be key in conferring invasion success. The importance of preadapted traits and release from natural enemies in successful invasion remains unclear, likely owing to a lack of empirical studies comparing their effects on relative performance and population growth of closely related species that differ in origin and invasiveness. A system of co-occurring native, introduced non-invasive, and invasive Eugenia congeners exists in south Florida, providing an opportunity to address deficiencies in our understanding of plant invasions by investigating the factors leading to invasion success for Eugenia uniflora. This approach is novel because very few studies have simultaneously incorporated both native and introduced non-invasive congeners into tests of these hypotheses, and no others have done so using this system of Eugenia congeners. The first study in this dissertation tested the ERH using an insect herbivore exclusion experiment in the field to compare the effects of natural enemies on the performance and population growth of Eugenia uniflora and its native congeners. The results showed that E. uniflora sustained more herbivore damage than its native counterparts, and that the effects of herbivores were sufficient to have negative impacts on performance and population growth. In sum, these findings contradict the ERH. Surprisingly, the vast majority of damage to E. uniflora was caused by the recently introduced Sri Lankan weevil (Myllocerus undatus), with which it shares no coevolutionary history. The second study compared seedling performance among native, introduced non-invasive, and invasive Eugenia congeners to determine if the success of E. uniflora can be attributed to superior performance traits. Invasive E. uniflora was found to outperform its native and introduced non-invasive counterparts in a number of seedling traits, including emergence, growth, and survival, in spite of sustaining higher levels of herbivore damage in the field. This result was consistent across years and sites, suggesting that superior performance may be an important factor in invasion success by E. uniflora. The final experiment investigated the role of enemy release on performance of native, introduced non-invasive, and introduced invasive Eugenia seedlings using an insect herbivore exclusion experiment in the field. In this study, the invasive E. uniflora was again found to sustain more damage by foliar herbivores compared to its native and introduced non-invasive counterparts. However, in spite of higher levels of herbivore damage, E. uniflora continued to outperform its congeners in terms of stem growth, and its congeners did not outperform E. uniflora in any attribute. Insect herbivores negatively affected survival of all species, but were found to have little effect on growth. In combination, the results of these studies indicate that the ability of E. uniflora to outperform its native and introduced congeners at the seedling stage, and not release from insect herbivores, may contribute to its success as an invader. Additionally, E. uniflora exhibits relatively low resistance to herbivory in the new range, and instead may possess an ability to tolerate moderate levels of damage. The implications of this study are that enemy release may not be important in determining invasion success in some systems, and that the accumulation of new enemies may mitigate the effects of invasive plants over time. The paucity of studies investigating interactions among invasive plants and herbivores that share no coevolutionary history warrants further research. Finally, this system of Eugenia congeners provides valuable opportunities to test additional hypotheses and to further explore factors leading to invasion success.

Revised; Originally Published: 2000 / 7 pp. / The mid elevations (3,500 to 6,000 feet) in Arizona can be ideal for growing tree fruit. Site selection can make a pronounced effect on how well fruit will grow and produce. The warmer the site the greater the chance of success. Areas where cold air settles are a poor choice for tree fruit production. Variety selection is very important for good fruit production.February and March are the best months to plant bare root trees, although they can be planted anytime during the dormant season. Try to plant 30 days before bud break. Containerized plants are best planted in late September through early October. The open center pruning system allows for more sunlight to reach all the branches of the tree. Whereas the central leader is used with those trees that are less vigorous. Training trees when young is an important step in ensuring a strong scaffold system when bearing. Fruit thinning helps to control fruit size and consistent bearing. Proper fertilization, irrigation, and pest control will promote healthy productive trees.

Dans cette thèse nous donnons une description complète de la dynamique d'une classe L de fonctions de degré un du cercle, supposées de classe (deux fois dérivable) C^2 à l'exception de deux points où seule la continuité est exigée, et telles qu'elles soient constantes sur un des intervalles délimité par ces derniers. De plus sur des demi-voisinages ouverts de ces points elles s'écrivent sous la forme x^l où l est un nombre réel positif appelé l'exposant critique de la fonction. Dans le chapitre 2 nous montrons pour la sous-classe de L des fonctions dont le nombre de rotation est de type borné, l'existence d'une transition dans la géométrie du système lorsque l'exposant critique traverse 2. Le cas plus général de fonctions en L avec nombre de rotation infinie est considéré dans le chapitre 3. Il devient pourtant plus délicat d'émettre des conjectures ; on rencontre parfois des surprises dues à laprésence de phénomènes paraboliques. De plus, nos résultats sur les applications du cercle nous permettent d'étudier l'intéressante théorie des flots de Cherry (chapitre 4). En particulier, on construit un exemple de tel flot qui a ensemble quasi-minimale métriquement non trivial. Nous donnons également une description complète des mesures physiques sur ce flot. Dans le chapitre 5 nous construisons un contrexemple de Denjoy qui est un difféomorphisme (indéfiniment dérivable) C^∞ partout sauf dans un point qui est demi-critique plat pour la fonction.

Submitted by Auxiliadora Costa (aucydj@gmail.com) on 2018-11-12T19:39:40Z No. of bitstreams: 1 CÍCERO FÁBIO DE SOUSA ALVARENGA - DISSERTAÇÃO PPGSA PROFISSIONAL 2018.pdf: 1415831 bytes, checksum: a9e73011cb749ab8dac93b727b3644ad (MD5) / Made available in DSpace on 2018-11-12T19:39:40Z (GMT). No. of bitstreams: 1 CÍCERO FÁBIO DE SOUSA ALVARENGA - DISSERTAÇÃO PPGSA PROFISSIONAL 2018.pdf: 1415831 bytes, checksum: a9e73011cb749ab8dac93b727b3644ad (MD5) Previous issue date: 2018-03-05 / A utilização de água salina em áreas irrigadas no semiárido brasileiro tem se intensificado, principalmente, devido os longos períodos de estiagem, resultando em diminuição do crescimento e produtividade das culturas, em consequência dos efeitos osmóticos, tóxicos e desequilíbrio nutricional, quais podem ser mitigados pelo manejo da adubação. Neste sentido, objetivou-se com a pesquisa avaliar o efeito de diferentes salinidades na água de irrigação em interação com combinações de adubações nitrogenada e potássica sobre o crescimento e fisiologia de plantas de aceroleira, aos 200 dias após o transplantio. O experimento foi realizado em campo, no CCTA/UFCG, em delineamento de blocos ao acaso, com os tratamentos dispostos em esquema fatorial 5 x 4, referentes a cinco salinidades da água de irrigação ajustadas para condutividades elétricas (CEa) de 0,3; 1,3; 2,3; 3,3 e 4,3 dS m-1 em interação com quatro combinações (NK) de doses de nitrogênio (N) e potássio (K2O), sendo NK1 = 70%N + 50%K2O; NK2 = 100%N + 75%K2O; NK3= 130%N + 100%K2O e NK4= 160%N + 125%K2O. Foram utilizadas três repetições e parcela composta por um lisímetro de 60 Litros contendo uma planta, totalizando 60 lisímetros no experimento. Utilizou-se a cv. Flor Branca, enxertada sobre porta-enxerto da cv. Junco. Constatou-se que a maioria das variáveis de crescimento e fisiológicas não foram comprometidas pela irrigação com salinidade da água de até 4,3 dS m-1. Não houve mitigação do estresse salino pela combinação das doses de adubação nitrogenada e potássica sobre o diâmetro do caule abaixo da enxertia e diâmetro de ramos primários afetados pela salinidade da água. A combinação das doses de 70%N (35 g de N) + 50% K2O (20 g de K2O) promoveram, de forma isolada, aumento das trocas gasosas e o maior crescimento das plantas de aceroleira. / The use of saline water in irrigated areas in the Brazilian semi-arid region has intensified mainly due to the long periods of drought, resulting in reduced crop growth and productivity, as result of osmotic, toxic and nutritional imbalance effects, which may be mitigated by management of manuring. In this sense, the objective of the research was to evaluate the effect of different salinities on irrigation water in interaction with combinations of nitrogen and potassium fertilizations on the growth and physiology of acerola plants at 200 days after transplanting. The experiment was realized in the field at the CCTA / UFCG, in a in a lineation block design, with treatments disposed in a 5 x 4 factorial scheme, referring to five irrigation water salinities adjusted for electrical conductivity (CEa) of 0.3; 1,3; 2,3; 3.3 and 4.3 dS m-1 in interaction with four combinations (NK) of nitrogen (N) and potassium (K2O) doses, with NK1 = 70% N + 50% K2O; NK2 = 100% N + 75% K2 O; NK 3 = 130% N + 100% K 2 O and NK 4 = 160% N + 125% K 2 O. Three replicates were used andplot consisting of a lysimeter of 60 Liters containing a plant, totaling 60 lysimeters in the experiment. The cv. White flower, grafted on rootstock cv. Reed. It was found that the majority of growth and physiological variables were not compromised by irrigation with water salinity up to 4.3 dS m-1. There was no salt stress mitigation by the combination of nitrogen and potassium fertilization rates on stem diameter below grafting and diameter of primary branches affected by water salinity. The combination of the doses of 70% N (35 g of N) + 50% K2O (20 g of K2O) promoted, in an isolated way, increased gas exchange and the highest growth of the acerola plants.

A estabilidade à oxidação é uma das propriedades mais importantes do biodiesel pois afeta a sua estabilidade durante o período de estocagem influenciando no desempenho do motor. As pesquisas atuais tendem a desenvolver aditivos antioxidantes para melhorar sua estabilidade. Algumas plantas exibem propriedades antioxidantes devido à sua composição química e que podem auxiliar nessa estabilização. O objetivo deste trabalho foi estudar a estabilidade termo oxidativa do biodiesel de soja e do sebo bovino puro e aditivado com folhas e extrato das folhas de acerola, graviola, manga e pitanga frente à luz, a 60º C e a baixas temperaturas por 0, 168, 504, 1176 e 1848 h de estocagem de forma a avaliar o seu enquadramento dentro das normas ANP, ASTM, EN. As folhas usadas como aditivo antioxidante foram moídas num moinho de facas a 10 mesh e os extratos das folhas foram obtidos pelo processo Soxhlet. O biodiesel de soja foi obtido pela rota etílica e o de sebo bovino pela metílica. A estabilidade termo oxidativa foi monitorada determinando-se o índice de acidez, a viscosidade cinemática, a densidade, por espectroscopia no infravermelho com Transformada de Fourier e por termogravimetria. Os resultados mostraram que o biodiesel de soja e do sebo bovino é estável frente à luz após 1848 h. O efeito antioxidante das folhas sobre o biodiesel de soja após 168 h de estocagem a 60º C segue a seguinte ordem: folhas de graviola > folhas de pitanga > folhas de manga > folhas de acerola, enquanto para o extrato das folhas tem-se: extrato das folhas de acerola> extrato das folhas de graviola>extrato das folhas de manga>extrato das folhas de pitanga, após 504h. Para o biodiesel de sebo bovino as folhas apresentaram a ordem: folhas de pitanga>folhas de acerola >folhas de manga>folhas de graviola, e para os extratos a ordem: extratos da folha de manga > extratos da folha de graviola >extratos da folha de pitanga>extratos da folha de acerola. O butil hidroxitolueno (BHT), antioxidante sintético, apresentou maior efeito antioxidante sobre o biodiesel de soja em relação às aditivações com folhas e seus extratos após 1176h. No biodiesel de sebo bovino, a atividade do BHT foi semelhante aos extratos das folhas de acerola, graviola e pitanga após 504h e o de manga após 1176h. A ordem da estabilidade do biodiesel de soja aditivado frente a baixas temperaturas foi: extrato de pitanga > extrato de manga > extrato de acerola > extrato de graviola. Os resultados dos testes em baixa temperatura indicam que o biodiesel de soja aditivado ou não pode ser usado em qualquer região do país para todas as estações do ano. O efeito dos extratos das folhas na estabilidade do biodiesel frente a baixas temperaturas foi: extratos das folhas de manga>extratos de acerola>extratos de graviola>extratos de pitanga. O biodiesel de sebo bovino puro apresenta menor estabilidade frente a baixas temperaturas em relação ao biodiesel de soja. Os resultados obtidos do IA, viscosidade cinemática, densidade, FTIR e TGA indicam que as folhas e extratos das folhas das frutas estudadas podem atuar como aditivos antioxidantes na estabilidade oxidativa do biodiesel. / Oxidation stability is one of the most important properties of biodiesel because it affects their stability during the storage period influence on engine performance. Current research tend to develop antioxidant additives to improve their stability. Some plants have antioxidant properties due to their chemical composition and may assist in this stabilization. The aim of this study was to oxidative term stability of soybean biodiesel and pure beef tallow and spiked with leaves and extracts of the leaves of cherry, soursop, mango and cherry front light, 60 ° C and low temperatures for 0, 168, 504, 1176 and 1848 h of storage in order to evaluate its framework within the ANP, ASTM, EN. The leaves used as an antioxidant additive were ground in a knife mill to 10 mesh and extracts of leaves were obtained by Soxhlet process. Soybean biodiesel was obtained by the ethyl route and beef tallow by methyl. The term oxidative stability was monitored by determining the acid number, kinematic viscosity, density, by infrared spectroscopy with Fourier Transform and thermogravimetry. The results showed that the biodiesel soya and tallow is stable against the light for 1848 h. The antioxidant effect of leaves on soybean biodiesel after 168 h of storage at 60 ° C follows the following order: leaves of soursop> sheets of cherry> mango leaves> acerola leaves while for the leaves of the statement we have: extract leaves acerola> extract of the leaves of soursop> extract of mango leaves> extract of cherry leaves after 504h. For the leaves beef tallow biodiesel showed the order: leaves of cherry> leaves acerola> mango leaves> soursop leaves and extracts the order: Mango leaf extracts> soursop leaf extracts> leaf extracts of cherry> acerola leaf extracts. The butylated hydroxytoluene (BHT), synthetic antioxidant, showed higher antioxidant effect on soybean biodiesel in relation to additivations with leaves and their extracts after 1176h. In beef tallow biodiesel BHT activity was similar to the extracts of the leaves of cherry, soursop and cherry after 504h and the sleeve after 1176h. The order of stability of soy biodiesel additive against low temperatures was: cherry extract> mango extract> acerola extract> soursop extract. The results of the tests indicate that low temperature soybean biodiesel additive or may not be used in any region of the country for all seasons. The effect of the extracts of leaves in front biodiesel stability at low temperatures was: extracts of mango leaves> acerola extracts> soursop extracts> cherry extracts. Biodiesel pure beef tallow has lower stability in low temperatures to soy biodiesel. The results of the AI, kinematic viscosity, density, FTIR and TGA show that the extracts of the leaves and fruits studied sheets can act as antioxidant additives in the oxidative stability of biodiesel.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A agricultura orgânica ou agroecológica visa o estabelecimento e manutenção de sistemas agrícolas ecologicamente equilibrados e estáveis, com eficiência econômica, boa produção e seja eficiente na utilização dos recursos naturais. Em geral, a agroecologia usa a adubação orgânica como fonte de nutrientes às culturas,empregando-se o uso de biofertilizantes Esta pesquisa compreendeu dois experimentos realizados concomitantemente em ambiente protegido no campus Cauamé da Universidade Federal de Roraima UFRR, com tomate cereja (Solanum lycopersicum var. cerasiforme) BRS Iracema e dois diferentes tipos de biofertilizante (comum e enriquecido) aplicados no solo dos baldes de cultivo que apresentavam capacidade de 12dm3 previamente peneirado e calcareado. A irrigação foi por gotejamento de acordo com a evaporação do tanque classe A e a necessidade da cultura. O primeiro experimento objetivou avaliar o efeito de diferentes doses de biofertilizante comum no desenvolvimento vegetativo e reprodutivo do tomate cereja BRS Iracema. O delineamento experimental foi em blocos casualizados (DBC) com uso de biofertilizante diluído em 5 proporções (0, 686, 960, 1600 e 2400 mL, compreendendo os tratamentos T1, T2. T3, T4 e T5 respectivamente) com 4 repetições. Para as variáveis vegetativas, foi observado que o aumento das doses de biofertilizante comum, proporcionou elevação nos valores da massa seca de folhas, assim como para massa fresca e seca de talos, atribuindo os melhores resultados para os tratamentos 4 e 5. As doses de biofertilizante influenciaram significativamente a massa seca de folhas, massa fresca e secade talos, sendo possíveis ajustes quadráticos com valores máximos obtidos entre 1275 e 2050 mL/planta. Entretanto, para o número de frutos e produção, as doses deste biofertilizante influenciaram linearmente. O segundo experimento objetivou avaliar o efeito de diferentes doses de biofertilizante enriquecido no desenvolvimento vegetativo e reprodutivo do tomate cereja BRS Iracema. O delineamento experimental foi em blocos casualizados (DBC) com uso de biofertilizante diluído em 5 proporções (0, 686, 960, 1600 e 2400 mL, compreendendo os tratamentos T1, T2. T3, T4 e T5 respectivamente) com 4 repetições.O aumento da dose de biofertilizante enriquecido proporcionou aumento nos valores de massa fresca e seca de folhas e talos, possibilitando ajustes quadráticos. Enquanto, o biofertilizante influenciou linearmente amassa seca de raiz. A dose de 2208 ml propiciou maior número de frutos (685 frutos por planta). Porém, as doses não influenciaram na produtividade. / The organic and agroecological farming aims at establishing and maintaining an ecologically balanced and stable agricultural systems, with economic efficiency, good production and be efficient in the use of natural resources. In general, the agroecology uses organic manure as a nutrient source for crops, employing the use of biofertilizers This research included two experiments was conducted in the Universidade Federal de Roraima (UFRR) with cherry tomato (Solanum lycopersicum var. cerasiforme) BRS Iracema and two different types of biofertilizer(ordinary and enriched) applied to the soil of the crop which buckets capacity 12dm3 had previously sieved and limestoned. The drip irrigation was in accordance with the evaporation of class pan A and the need for crop. The first experiment aimed to evaluate the effect of different doses of ordinarybiofertilizers (only bovine biofertilizers) on vegetative and reproductive development of cherry tomato BRS Iracema. The experimental design was a randomized block designwith use of biofertilizers diluted in five ratios (0, 686, 960, 1600 and 2400 mL) with four repetitions. For vegetative variables, it was observed that increasing doses of ordinarybiofertilizer resulted in higher values of the dry mass of leaves, as well as fresh and dry weight of stems. Doses biofertilizer significantly influenced the dry mass of leaves, fresh and dry mass of stems, with possible adjustments quadratic with maximum values between 1275 and 2050 mL/plant. However, the treatments influenced linearly the number of fruits and production. The second experiment aimed to evaluate the effect of different doses of enriched biofertilizer on vegetative and reproductive development of cherry tomato BRS Iracema. The experimental design was a randomized block design with use of enriched biofertilizers diluted in five ratios (0 , 686, 960 , 1600 and 2400 mL/plant with fourrepetitions.The dose of enriched biofertilizer provided an increase in the values of fresh and dry weight of leaves and stems, allowing quadratic adjustments. While the biofertilizer influenced linearly the root dry weight. The enrichedbiofertilizer (2208 ml/plant)provided greater number of fruits (685 fruits per plant), but the doses had no effect on yield.

Zur Modellierung der Ausbreitung von Aktionspotentialen im menschlichen Vorhof wurde in der Vergangenheit eine Vielzahl von Modellen entwickelt, welche den Einfluss der zahlreichen Ionenströme, die durch die Zellmembran fließen, im Detail berücksichtigen. Mit dem Ziel einer vereinfachten Beschreibung ist kürzlich das Modell von Bueno-Orovio, Cherry und Fenton (BOCF-Modell) an die Elektrophysiologie des Vorhofs angepasst worden, welches ursprünglich für die elektrische Erregungsausbreitung in den Herzkammern entwickelt wurde. In dieser Arbeit wird dieses angepasste BOCF-Modell in Bezug auf seine Fähigkeit untersucht, raum-zeitliche Erregungsmuster zu erzeugen, die beim anatomischen und spiralförmigen Reentry gefunden werden. Hierzu werden die Ergebnisse des BOCF-Modells mit denen des detaillierten Modells von Courtemanche, Ramirez und Nattel (CRN-Modell) verglichen. Es zeigt sich, dass die charakteristischen Merkmale von Reentry-Mustern im CRN-Modell gut mit dem BOCF-Modell wiedergegeben werden. Dies eröffnet die Möglichkeit, die Ursprünge des Vorhofflimmerns basierend auf einer vereinfachten, aber immer noch zuverlässigen Beschreibung der Elektrophysiologie zu untersuchen. Eine effektive Methode wird entwickelt, um empirische Aktionspotentiale von Patienten in den menschlichen Vorhöfen anhand des BOCF-Modells zu modellieren. Grundlage dieser Methode ist die Anpassung von drei relevanten Zeitkonstanten im BOCF-Modell mit Hilfe eines nicht-linearen Optimierungsverfahrens. Die Methode ermöglicht, spezifische Aktionspotentiale mit einer gegebenen Amplitude, Breite und Form zu reproduzieren. Sie kann als Prädiktor für pathologische Befunde verwendet werden.

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My thesis is about transforming the Anacostia waterfront with a rhythmic approach to seamlessly integrate it into the overall fabric of Washington, D.C. My design involves establishing seasonal celebrations throughout the year, including a redbud festival, and zooming in, to craft a space that celebrates the rich dance culture of Anacostia. My thesis goal is to foster a celebratory atmosphere through an interconnected design that harmonizes with its environment. My research involves exploring the relationship between dance, architecture, and trees to create an experience that would be enjoyed by the community and to bring people to Anacostia, which has historically been a neglected part of the city. The Anacostia Redbud Festival will be the waterfront's own version of the Cherry Blossom Festival, it'll be an opportunity for a celebration of this Native tree and to increase the city's tree canopy. It's a transformative approach for the Anacostia Waterfront as a whole, and I'll be proposing an overall, rhythmic site plan to enhance the recreational experience there. Zooming in, I chose a particular portion from my overall site proposal to intervene and place my dance structure. My design approach has been to explore vertical elements along with trees to create structural movement to mimic dance. Jazz dance will be the foundation that my design will be based upon. I chose Jazz instead of Classic Ballet, which is universally known as the foundation of dance, to teach people that idea is euro-centric and neglects the history of other dance types. Jazz dance was invented by African slaves who shared it when they were brought to the U.S., they never codified it so white people took the chance to claim it for themselves. My design will be a celebration of Black culture and teach people who the true pioneers of Jazz dance are and how that's the true foundation of all dance. Approaching the design of my structure, the idea of having an inhabitable roof took precedence because it allows for the structure to seamlessly intertwine with the existing park. The inhabitable roofs are made from long ramps that bring you from the ground to a rooftop experience that reaches into the surrounding tree canopy. The rooftop also has different pockets where one can find platforms to perform on or to just relax on. This whole ramp structure sits on top a dance pavilion that houses a casual theater, dance studios, gallery spaces and a café, allowing people to also enjoy dance inside and outside, blurring the lines between architecture and landscape. Furthermore, the building is surrounded by small vertical poles that act as structural elements, as well as an important façade element for shading. The small poles are placed in a loose order to imitate a forest of trees. The ramps and orientation of the building give emphasis to the new 11th street bridge structure that will be coming to Anacostia and overall creating a vibrant park that encourages movement and celebrates true D.C. culture. / Master of Architecture / This work holds significant value in its ability to transform the Anacostia waterfront into a vibrant cultural hub. It brings together the community through seasonal celebrations and highlights the rich heritage of dance, particularly jazz dance, which is deeply rooted in African American culture. By challenging Euro-centric narratives and educating the public about the true origins of jazz dance, the project fosters a greater appreciation for diverse cultural contributions. The importance of this project lies in its potential to revitalize a historically neglected area, drawing visitors and investment to Anacostia. By enhancing the city's tree canopy and creating a unique cultural destination, the project contributes to environmental sustainability and urban beautification. The impact creates a dynamic recreational space that encourages physical activity and cultural engagement. The integration of architecture and nature offers an immersive experience that blurs the lines between architecture and nature, promoting a deeper connection to both. Ultimately, this project has the potential to transform the Anacostia waterfront into a celebrated part of Washington, D.C., enriching the lives of residents and visitors alike.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-10-19T17:51:25Z No. of bitstreams: 1 2013 - Ellen Almeida dos Santos Ferreira.pdf: 1317610 bytes, checksum: dd687bdd4e12dc0f868a15a961aa31ed (MD5) / Made available in DSpace on 2018-10-19T17:51:25Z (GMT). No. of bitstreams: 1 2013 - Ellen Almeida dos Santos Ferreira.pdf: 1317610 bytes, checksum: dd687bdd4e12dc0f868a15a961aa31ed (MD5) Previous issue date: 2013-05-06 / Brazil is a big producer and exporter of fruits and fruit juice. The sale, in many cases, is limited to the seasonality of production and perishability of fruits. The Brazilian cherry is a tropical fruit originally from the South and Southeast regions of Brazil, with high perishability and susceptibility to physical damage during transport. Considering all the losses that the productive chain of fresh Brazilian cherry may suffer, it is evident the importance of producing the juice of this fruit. Traditionally, thermal treatment has been employed in the processing and preservation of these products; however, undesirable changes in sensory and nutritional characteristics can happen. Among the innovative technologies to reduce these undesirable changes is High Hydrostatic Pressure (APH). This method of food preservation provides additional benefits to the product allowing products closer to the fresh product. This study aimed to investigate the process of high pressure in the preservation of Brazilian cherry pulp (Eugenia uniflora L.) to assess their microbiological safety and sensory quality and nutritional nectar obtained. The study was conducted at Embrapa Food Technology (Rio de Janeiro-RJ, Brazil). The Brazilian cherry pulp was processed by high hydrostatic pressure using different pressure levels, temperatures and retention time, following a central composite design. Microbiological analyzes were performed (for Salmonella spp., Coliforms at 45? C, mesophilic aerobic, yeasts and molds), physico-chemical (pH, acidity, soluble solids, fibers), antioxidant activity and instrumental color. It was investigated nectar microbiological shelf life obtained from the pressurized pulp. Shelf life estimation through Survival Analysis was also carried out, and the nectar exceeded 35 days of storage. Further studies are recommended. The sensory characteristics of nectars obtained from the pressurized pulp, non-pressurized pulp (Control), pasteurized Control, and three commercial brands available in the market were evaluated by consumer acceptance and through the methodology check all that apply (CATA). Data were analyzed using analysis of variance, Tukey test, and Multiple Factor Analysis. The high pressure process has been effective in preserving the nectar refrigerated for up to 35 days. There was no significant negative effect on antioxidant activity and color of the samples subjected to high pressure. The results obtained in the determination of "ideal" pulp concentration and sweetness for the nectar formulation cherry were 36% and 10%, respectively. In Acceptance Test samples pressurized and commercial B had the highest scores and the terms most frequently used in the methodology check all that apply were reddish, cherry flavor, presence of particles, attractive color, acid, astringent, off-flavor, sweet, bitter, gritty look. Such terms are therefore considered the most suitable to describe the samples by consumers. / O Brasil ? um grande produtor e exportador de frutas e suco de frutas. A comercializa??o, em muitos casos, ? limitada ? sazonalidade da produ??o e ? perecibilidade das frutas. A pitanga ? uma fruta tropical origin?ria das regi?es Sul e Sudeste do Brasil, com alta perecibilidade e susceptibilidade a danos f?sicos durante o transporte. Tendo em vista todas as perdas que a cadeia produtiva da pitanga in natura pode sofrer, fica evidente a relev?ncia da obten??o do suco deste fruto. Tradicionalmente o tratamento t?rmico tem sido empregado no processamento e conserva??o destes produtos; no entanto, altera??es indesej?veis nas caracter?sticas nutricionais e sensoriais podem acontecer. Entre as tecnologias inovadoras para redu??o dessas altera??es indesej?veis, est? a Alta Press?o Hidrost?tica (APH). Este m?todo de conserva??o de alimentos oferece benef?cios adicionais ao produto permitindo a obten??o com caracter?sticas mais pr?ximas do produto in natura. Este estudo teve como objetivo investigar o processo de alta press?o na conserva??o de polpa de pitanga (Eugenia uniflora L.) de modo a avaliar a seguran?a microbiol?gica e a qualidade sensorial e nutricional do n?ctar obtido. O trabalho foi realizado na Embrapa Agroind?stria de Alimentos (Rio de Janeiro, RJ, Brasil). A polpa de pitanga foi processada por alta press?o hidrost?tica utilizando diferentes n?veis de press?o e tempo de reten??o, seguindo delineamento experimental do tipo composto central. Foram realizadas an?lises microbiol?gicas (para Salmonella spp., coliformes ? 45?C, aer?bios mes?filos e fungos filamentosos e leveduras), f?sico-qu?micas (pH, acidez, s?lidos sol?veis, fibras), atividade antioxidante, cor instrumental e avalia??o sensorial. Foi avaliada a vida ?til microbiol?gica do n?ctar obtido a partir da polpa pressurizada e sensorialmente atrav?s da an?lise de sobreviv?ncia (Survival Analysis). O n?ctar apresentou vida ?til superior a 35 dias, necessitando estudos subsequentes. As caracter?sticas sensoriais dos n?ctares obtidos a partir da polpa pressurizada, da polpa n?o pressurizada (controle), do controle pasteurizado e de tr?s marcas comerciais dispon?veis no mercado foram avaliadas atrav?s da aceita??o do consumidor e utilizando a metodologia check all that apply (CATA). Os dados foram analisados por An?lise de Vari?ncia, teste de m?dia, e An?lise M?ltipla de Fatores. O processamento da polpa por alta press?o foi eficaz na preserva??o do n?ctar refrigerado por at? 35 dias. N?o houve efeito negativo da APH na atividade antioxidante das amostras. Nas an?lises de cor todos os par?metros analisados (L*, a* e b*) diferiram (p<0,05) do controle (polpa n?o pressurizada) e as amostras pressurizadas. Os resultados obtidos na determina??o de concentra??o de polpa e do?ura ?ideais? para a formula??o do n?ctar de pitanga foram 36% e 10%, respectivamente. No Teste de Aceita??o as amostras pressurizada e comercial B obtiveram as maiores m?dias e na metodologia check all that apply, os termos utilizados mais frequentemente como descritores foram cor avermelhada, sabor de pitanga, presen?a de part?culas, cor atrativa, ?cido, adstringente, sabor estranho, gosto doce, gosto amargo, aspecto arenoso. Tais termos podem ser, portanto, considerados os mais apropriados na descri??o das amostras pelos consumidores.