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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.
181

THE USE OF ALTERNATIVE NORMALIZATION APPROACHES TO UNDERSTAND CHANGES IN SARS-CoV-2 CONCENTRATIONS IN WASTEWATER

Isaksson, Frida January 2022 (has links)
Following the detection of SARS-CoV-2 RNA fragments in wastewater in March 2020, the use of wastewater-based epidemiology is rapidly emerging as a non-invasive approach to assessing community wide COVID-19 prevalence. Wastewater-based epidemiology is promoted as a complement to clinical testing in terms of improving public health authorities’ preparedness and supporting them in taking required interventions to protect the public health.  To utilize the occurrence of SARS-CoV-2 in wastewater in a public health context and evaluate trends in viral prevalence on a community level, robust data interpretation is required. This master's thesis work examines what is currently known about the factors that influence the concentrations of SARS-CoV-2 in wastewater, as well as the impact of alternative normalization approaches on the relationship between viral wastewater data and clinical case numbers. The work is divided into two parts where this report provides a state-of-the-art review as well as an overview of key findings in the accompanied scientific paper.  The study involved collection of wastewater samples from two different sized wastewater treatment plants (WWTPs) in Luleå municipality, between January and March 2021.  Concentrations of SARS-CoV-2 RNA were quantified in each sample as well as concentrations of total nitrogen (TN), total phosphorus (TP) and pepper mild mottle virus (PMMoV). Average daily WWTP flow and environmental data (precipitation and temperature) were continuously measured over the sampling period. The population size was estimated based on mass loads of TN and TP and literature values of the domestic contribution of these parameters to the sewer system. The viral wastewater data was normalized using the estimations of population size, census data, WWTP flow and PMMoV. The impact of the alternative normalization approaches was evaluated using statistical analyses to explore the relationship to clinical case numbers.  The result showed that the strength of the correlation between the different normalization approaches and clinical case data differed between the WWTPs. However, within each WWTP the differences in correlation between the different normalization approaches and clinical cases were not significant. Moreover, normalization using WWTP flow (i.e., viral loads) showed a stronger correlation to clinical cases compared to population and PMMoV normalized viral loads. However, when comparing wastewater data between the two catchment areas, the normalization approaches utilizing population (either census or TN and TP estimated population) or PMMoV better reflect the number of clinical cases. Additionally, according to time-shifted analysis, wastewater data of SARS-CoV-2 RNA predated an increase in clinical cases by 0-2 and 5-8 days, respectively, for the larger and smaller WWTPs.
182

Oleoresin Capsicum: an Analysis of the Implementation of Pepper Spray into the Law Enforcement Use of Force Continuum in a Selected Police Department.

Adkins, Lydia Denise 11 August 2003 (has links) (PDF)
This study focused on the use of oleoresin capsicum (OC) as a means of force and also tested the effectiveness of OC. A medium-size police agency was studied from 1991-2001. The following reports were collected for analysis: excessive force reports, reports of officers injured during arrests, use of hands-on restraint, and use of police baton. This study revealed an increase in reported incidents of excessive force and a reduction in the number of officers injuired making arrests while using various defensive techniques. Implementing OC into the force continuum remains a solid decision in review of this research. This study has shown oleoresin capsicum to be a safe, effective level in the law enforcement force continuum.
183

Sociala robotar inom vården: tekniska förutsättningar, fördelar, utmaningar och etiska överväganden / Social robots in healthcare: technical prerequisites, advantages, challenges, and ethical considerations

Oweidat, Mohanad, Aburas, Qassem January 2023 (has links)
Denna studie undersöker fördelarna, utmaningarna och etiska konsekvenserna av att använda sociala robotar i vården, som uppfattas av vårdpersonal och allmänheten. Syftet är att utvärdera acceptansen och integrationen av sociala robotar genom att ta itu med båda intressenternas problem och krav. Med fokus på robotar som Pepper och Paro, utforskar studien deras potentiella fördelar och utmaningar inom hälsovårdsmiljöer. Den undersöker också de etiska aspekter som bör vägleda deras utformning och implementering, såväl som de nödvändiga tekniska förutsättningarna för framgångsrik implementering. Resultaten pekar på fördelar såsom avlastning från administrativa uppgifter, ökad effektivitet, och förbättrad patientvård med stöd för emotionellt välbefinnande. Utmaningar inkluderar nödvändig utbildning för vårdpersonal, tekniska risker och svårigheten att helt ersätta mänsklig interaktion. Dessutom att bygga förtroende för dessa robotar genom transparent kommunikation om deras roller och begränsningar är avgörande för deras acceptans. Vi har identifierat viktiga riktlinjer för en ansvarsfull användning av sociala robotar inom vården: 1. Integritet och Dataskydd 2. Säkerhet 3. Autonomi och Delaktighet 4. Mänsklig Värdighet 5. Samtycke När det gäller funktionalitet är tillförlitlighet och användarvänlighet avgörande. Robotar bör fungera korrekt, minimera tekniska problem, för att leverera tillförlitliga resultat. Användarvänlighet, inklusive intuitiva gränssnitt, är avgörande för sömlösa interaktioner mellan vårdpersonal, patienter och robotar. Dessutom är säkerhetsaspekter avgörande för säker implementering. Att integrera robusta säkerhetsfunktioner och skydda mot cyberhot och obehörig åtkomst till patientinformation är nyckelprioriteringar. Integration med befintliga hälso- och sjukvårdsprocesser och system bör vara smidig för att minimera störningar och säkerställa kompatibilitet. Genom att ta itu med etiska, funktionella och säkerhetsaspekter kan sociala robotar effektivt sättas in i vården, förbättra patientvården och förbättra arbetsmiljön för vårdpersonal. Den här forskningen ger insikter i de potentiella fördelarna och utmaningarna med implementering av sociala robotar i vården, och informerar utvecklingen av en genomtänkt strategi för deras ansvarsfulla användning. / This study explores the benefits, challenges, and ethical consequences of using social robots in healthcare, as perceived by healthcare professionals and the general public. The aim is to assess the acceptance and integration of social robots by addressing the concerns and requirements of both stakeholders. Focusing on robots like Pepper and Paro, the study investigates their potential advantages and challenges in healthcare environments. It also examines the ethical aspects that should guide their design and implementation, as well as the necessary technical prerequisites for successful implementation. The results indicate advantages such as relief from administrative tasks, increased efficiency, and improved patient care with support for emotional well-being. Challenges include the need for training healthcare staff, technical risks, and the difficulty of fully replacing human interaction. Furthermore, building trust in these robots through transparent communication about their roles and limitations is crucial for their acceptance. We have identified key guidelines for responsible use of social robots in healthcare: 1. Privacy and Data Protection 2. Security 3. Autonomy and Participation 4. Human Dignity 5. Consent Regarding functionality, reliability and user-friendliness are critical. Robots should operate correctly, minimize technical issues, and deliver reliable results. User-friendliness, including intuitive interfaces, is essential for seamless interactions between healthcare professionals, patients, and robots. Additionally, security aspects are crucial for safe implementation. Integrating robust security features and protecting against cybersecurity threats and unauthorized access to patient information are top priorities. Integration with existing healthcare processes and systems should be smooth to minimize disruptions and ensure compatibility. By addressing ethical, functional, and security aspects, social robots can be effectively deployed in healthcare, improving patient care and enhancing the working environment for healthcare professionals. This research provides insights into the potential benefits and challenges of implementing social robots in healthcare and informs the development of a thoughtful strategy for their responsible use.
184

Novel neuroprotective compounds for use in Parkinson's disease

Shubbar, Ahmed 25 November 2013 (has links)
No description available.
185

Quality Changes in Grafted Pepper (Capsicum annumm L.) Scion Fruit

Fisk, Tylar S. January 2017 (has links)
No description available.
186

Effect of continued and regulated deficit irrigation on the productivity of four vegetable crops in open-field conditions in the Mediterranean area

Abdelkhalik, Abdelsattar Gamal Abdelsattar 27 September 2020 (has links)
Tesis por compendio / [ES] La escasez de agua se está convirtiendo en un problema en zonas áridas y semiáridas del mundo, donde se localiza parte de la producción de los principales cultivos hortícolas, como en el área mediterránea. La sequía es uno de los principales factores limitantes en la agricultura y está afectando gravemente a la producción de cultivos hortícolas. La mejora de la productividad del agua en la agricultura puede lograrse mediante la utilización de determinadas estrategias. El riego deficitario consiste en el aporte de agua por debajo de las necesidades de riego (NR) de los cultivos, de manera que se produce una reducción de la evapotranspiración. Puede realizarse de manera continua o sostenida (RDS) o controlada (RDC). Con el riego deficitario se puede mejorar la eficiencia del uso del agua de riego, manteniendo el rendimiento, e incluso en ocasiones, podría mejorarse la calidad de la cosecha. En este estudio, realizado en el Centro Experimental Cajamar de Paiporta (Valencia) se evalúa el efecto del riego deficitario en cuatro de los principales cultivos hortícolas cultivados al aire libre, en el área mediterránea: coliflor, cebolla, pimiento y sandía. En la evaluación se ha analizado: crecimiento y estado hídrico de las plantas, rendimiento, eficiencia del uso del agua de riego, calidad de la producción y rentabilidad de los cultivos. En la primera campaña se ensayó el RDS, lo que permitió establecer las diferentes etapas de crecimiento de cada cultivo, que se utilizaron en las siguientes campañas en el RDC. En los cuatro cultivos, las plantas control (100% NR) han mostrado un adecuado estado hídrico, tanto en el contenido relativo de agua como en el índice de estabilidad de la membrana, mientras que las sometidas a un RDS severo, han mostrado los menores valores de ambos índices. El efecto negativo del riego deficitario sobre el rendimiento ha resultado menos importante en los cultivos de otoño-invierno que en los cultivos de primavera-verano, especialmente en la coliflor. El RDS del 50% NR ha reducido drásticamente el rendimiento comercial y, consecuentemente, los ingresos brutos, aunque haya supuesto una mejora en la eficiencia del uso del agua de riego para los cultivos de otoño-invierno. Del análisis individual de los cultivos se deduce que el rendimiento en pellas de coliflor obtenidas con RDS al 75% NR o RDC al 50% NR durante la fase juvenil, se ha mantenido en niveles similares al control, mejorando la eficiencia del uso del agua de riego. En cebolla, en caso de restricción hídrica severa, sería aconsejable aplicar RDS con el 75% NR o RDC al 50% NR durante la maduración del bulbo, ya que estas estrategias han disminuido ligeramente el rendimiento, mejorando la eficiencia del uso del agua de riego. En condiciones menos restrictivas, RDC al 75% NR durante la maduración del bulbo ha dado lugar a un rendimiento satisfactorio, con un aumento de la eficiencia del uso del agua de riego. En pimiento dulce italiano, la aplicación de RDC al 75% NR durante la recolección ha dado lugar a una reducción considerable del rendimiento, y por tanto, de los ingresos brutos, aunque con importantes ahorros de agua y con un incremento en el contenido de sólidos solubles y de compuestos fenólicos de los frutos. Acortando el ciclo de cultivo hasta principios de septiembre, cuando ya se ha cosechado la mayor parte del rendimiento comercial, se conseguiría un importante ahorro de agua y permitiría utilizar la parcela en otros cultivos. El RDS al 75% y al 50% NR, o RDC al 50% NR durante la cosecha han dado lugar a una alta incidencia de frutos afectados por blossom-end rot. En sandía puede recomendarse la aplicación de RDC, tanto al 75% como al 50% NR durante la maduración del fruto, ya que ha conducido a rendimientos comerciales aceptables. De manera general se puede afirmar que la aplicación de RDS y de RDC en los cuatro cultivos, no ha afectado de manera importante a la calidad de la producción, / [CA] Resum L'escassesa d'aigua s'està convertint en un problema en zones àrides i semiàrides del món, on es localitza part de la producció dels principals cultius hortícoles, com és el cas de l'àrea mediterrània. La sequera és un dels principals factors limitants en l'agricultura i està afectant greument a la producció de cultius hortícoles. La millora de la productivitat de l'aigua en l'agricultura en general, i en l'horticultura en particular, es pot aconseguir mitjançant la utilització de determinades estratègies. El reg deficitari consisteix en l'aportació d'aigua per sota de les necessitats de reg (NR) dels cultius, de manera que es produeix una reducció de l'evapotranspiració. Es pot fer de manera contínua o sostinguda (RDS) o controlada (RDC). Amb el reg deficitari es pot millorar l'eficiència de l'ús de l'aigua de reg, mantenint el rendiment, i fins i tot de vegades, podria conduir a una millora de la qualitat de la collita. En aquest estudi, realitzat al Centre Experimental Cajamar de Paiporta (València, Espanya) s'avalua l'efecte del reg deficitari en quatre dels principals cultius hortícoles conreats a l'aire lliure, a l'àrea mediterrània: dos de cultiu de tardor-hivern (coliflor i ceba) i dues de cultiu primaveral-estival (pimentó i meló d'Alger). En l'avaluació s'han analitzat els següents paràmetres: creixement i estat hídric de les plantes, rendiment, eficiència de l'ús de l'aigua de reg, qualitat de la producció i rendibilitat dels cultius. A la primera campanya es va assajar el RDS, el que va permetre establir les diferents etapes de creixement de cada cultiu, que es van utilitzar en les següents campanyes en el RDC. En els quatre cultius, les plantes control (100% NR) han mostrat un adequat estat hídric, tant en el contingut relatiu d'aigua com en l'índex d'estabilitat de la membrana, mentre que les sotmeses a un RDS sever, han mostrat els menors valors d'ambdós índexs. L'efecte negatiu del reg deficitari sobre el rendiment ha resultat menys important en els cultius de tardor-hivern que en els cultius de primavera-estiu, especialment en la coliflor. El RDS del 50% NR ha reduït dràsticament el rendiment comercial i, conseqüentment, els ingressos bruts, encara que hagi suposat una millora en l'eficiència de l'ús de l'aigua de reg per als cultius de tardor-hivern. De l'anàlisi individual dels cultius es dedueix que el rendiment de coliflors obtingudes amb RDS al 75% NR o RDC al 50% NR durant la fase juvenil, s'ha mantingut en nivells similars al control, millorant l'eficiència de l'ús de l'aigua de reg. En ceba, en cas de restricció hídrica severa, seria aconsellable aplicar RDS amb el 75% NR o RDC al 50% NR durant la maduració del bulb, ja que aquestes estratègies han disminuït lleugerament el rendiment, millorant l'eficiència de l'ús de l'aigua de reg . En condicions menys restrictives, RDC al 75% NR durant la maduració del bulb ha donat lloc a un rendiment satisfactori, amb un augment de l'eficiència de l'ús de l'aigua de reg. En pimentó dolç italià, l'aplicació de RDC al 75% NR durant la recol·lecció ha donat lloc a una reducció considerable del rendiment, i per tant, dels ingressos bruts, encara que amb importants estalvis d'aigua i amb un increment en el contingut de sòlids solubles i de compostos fenòlics dels fruits. Retallant el cicle de cultiu fins a principis de setembre, quan ja s'ha collit la major part del rendiment comercial, s'aconseguiria un important estalvi d'aigua i permetria utilitzar la parcel·la en altres cultius. El RDS al 75% i al 50% NR, o RDC al 50% NR durant la collita han donat lloc a una alta incidència de fruits afectats per blossom-end rot. En meló d'Alger es pot recomanar l'aplicació de RDC, tant al 75% com al 50% NR durant la maduració del fruit, ja que ha conduït a rendiments comercials acceptables. De manera general es pot afirmar que l'aplicació de RDS i de RDC en els quatre cultius, no ha afectat de maner / [EN] Water scarcity is becoming a critical problem in arid and semi-arid areas of the world, where part of the production of the main horticultural crops is located, as is the case of the Mediterranean area. Drought is one of the main limiting factors in agriculture and it is seriously affecting the production of horticultural crops. The improvement of water productivity in agriculture in general, and in horticulture in particular, can be achieved through the use of certain strategies. Deficit irrigation consists of the supply of water below the irrigation water requirements (IWR), so that there is a reduction in evapotranspiration. It can be done continuously (CDI) or regulated (RDI). With deficit irrigation, the irrigation water use efficiency can be improved, maintaining yield, and it could even lead to an improvement in the quality of the harvest. This study, carried out at the Cajamar in Paiporta Experimental Center (Valencia, Spain), analyzes the effect of deficit irrigation on four of the main cultivated horticultural crops, open field cultivated in the Mediterranean area: two of autumnal-winter crops (cauliflower and onion) and two spring-summer crops (pepper and watermelon). In the evaluation, the following parameters have been analyzed: plant growth and water status, yield, irrigation water use efficiency, quality of production and crop profitability. In the first season the CDI was tested, which allowed to establish the different growth stages for each crop, which were used in the following season for the RDI. In the four crops, the control plants (100% IWR) have shown an adequate water status, in terms of both relative water content and membrane stability index, while those subjected to a severe CDI, have shown the lowest values of both indexes. The negative effect of deficit irrigation on yield has been less important in autumn-winter crops than in spring-summer crops, especially in cauliflower. The CDI at 50% IWR has drastically reduced the marketable yield and, consequently, the gross revenue, although it has supposed an improvement in the irrigation water use efficiency for the autumn-winter crops. From the individual analysis of the crops, it can be stated that cauliflower yield obtained with CDI at 75% IWR or RDI at 50% IWR during the juvenile phase, has remained at levels similar to the control, improving the irrigation water use efficiency. In relation to onion, in case of severe water restriction, it would be advisable to apply CDI with 75% IWR or RDI at 50% IWR during bulb ripening, since these strategies have slightly decreased yield, improving the irrigation water use efficiency. In less restrictive conditions, RDI at 75% IWR during the bulb maturation has led to a satisfactory yield, with an increase in the irrigation water use efficiency. In Italian sweet pepper, the application of RDI to 75% IWR during the harvesting has resulted in a considerable reduction of the yield, and therefore, of the gross income, although with important water savings and increasing the fruit soluble solids and phenolic compounds content. By shortening the cultivation cycle until the beginning of September, when most of the marketable yield has already been harvested, significant water savings would be achieved, and the land could be used in other crops. CDI at 75% IWR and 50% IWR, or RDI at 50% IWR at harvesting have resulted in a high incidence of fruit affected by blossom-end rot. In watermelon the RDI application can be recommended, both 75% and 50% IWR, during the fruit ripening, since it has led to acceptable marketable yields. In general terms, it can be affirmed that the application of CDI and RDI in the four crops has not significantly affected the product quality, in terms of the analyzed parameters. / My grateful thanks to the Cultural Affairs and Mission Sector, Egyptian Ministry of Higher Education for supporting me with a scholarship. / Abdelkhalik, AGA. (2019). Effect of continued and regulated deficit irrigation on the productivity of four vegetable crops in open-field conditions in the Mediterranean area [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/129868 / Compendio
187

Modelagem do balanço de energia do dossel da cultura do pimentão em casa de vegetação. / Canopy energy balance modeling of sweet pepper cultivated in greenhouse.

Atarassi, Roberto Terumi 19 January 2005 (has links)
Dentre os elementos em um sistema de produção em casa de vegetação, o dossel da cultura é o que mais afeta o microclima interno, sendo de grande importância o entendimento dos seus processos de troca de energia. Dada à complexidade da interação entre os vários elementos, a modelagem mostra-se como uma importante ferramenta para a pesquisa em ambientes protegidos, porém muito pouco utilizado no Brasil. O objetivo do presente trabalho foi o desenvolvimento de um modelo de simulação para estimativa dos componentes do balanço de energia do dossel da cultura do pimentão em casa de vegetação e sua calibração e teste com dados de um experimento de campo. Foi desenvolvido um modelo em equilíbrio dinâmico composto de quatro submodelos: fluxo de calor latente (λE), fluxo de calor sensível (H), balanço de ondas curtas (BOC) e balanço de ondas longas (BOL). Os submodelos para λE e H foram baseados em teorias de transferência de massa e calor por convecção mista associada a uma equação de estimativa da resistência estomática a partir de medidas climáticas. Os submodelos de BOC e BOL levaram em consideração a disposição em linhas da cultura, a cobertura parcial do dossel e o Índice de Área Foliar (IAF). O modelo foi implementado em planilha eletrônica MICROSOFT EXCEL 2000 e resolvido numericamente através de uma rotina escrita em linguagem VBA (Visual Basic para Aplicativos). O modelo foi calibrado e testado com experimento em casa de vegetação em arco com 17,5 x 6,4m, pé-direito de 3m e altura de arco de 1,2m, localizada no município de Piracicaba - SP, no Campus da Escola Superior de Agricultura "Luiz de Queiroz"/USP, cultivada com pimentão amarelo, em linha simples no espaçamento de 1,2m x 0,5m. Foram feitas medidas de ranspiração com lisímetro com células de carga, radiação global, difusa e fotossinteticamente ativa, velocidade do vento, temperatura e pressão atual de vapor e temperatura do dossel. Também se tomaram medidas da cultura como IAF, altura e diâmetro de copa. A partir dos levantamentos, o modelo foi calibrado e testado. O modelo não estimou de forma precisa os componentes do balanço de energia, mas foi capaz de acompanhar a variação dos valores reais levantados em experimento, ainda que em magnitudes diferentes, indicando a necessidade de uma calibração mais adequada, em especial dos coeficientes de extinção do dossel para radiação difusa e direta. A modelagem permitiu verificar a limitação de algumas abordagens encontradas em literatura e utilizadas neste trabalho, como na determinação das resistências aerodinâmica e estomática. / In a greenhouse production system, the canopy of culture is the main element that modifies the internal microclimate. Its comprehension is very important to understand the energy exchange process. Due to the complexity interaction among several elements, the modeling represents an important tool for research in protected environments, but little used in Brazil. The aim of the present work was to develop a simulation model for estimating the components of canopy energy balance of sweet pepper crop cultivated in greenhouse and its calibration and test with experimental data. It was developed a steady-state model divided in four submodels: latent heat flux (λE), sensible heat flux (H), short wave balance (BOC) and long wave balance (BOL). The λE and H submodels were based on the mixed convection mass and heat transfer theory, associated with equation to leaf stomatal resistance estimation using climatic data. The BOC and BOL submodels considered the row orientation of crop, partial cover of soil and leaf area index (IAF). The model was implemented in a Microsoft EXCEL 2000 and solved numerically with routine developed in VBA language (Visual Basic for Application) The model was calibrated and tested with experimental data from a greenhouse 17,5m long by 6,4m width, 3,0m height, localized in Piracicaba City, São Paulo, Brazil, in experimental area of "LUIZ DE QUEIROZ" College Of Agriculture - São Paulo University (USP), cultivated with sweet pepper crop, in single row, spaced in 1,2m x 0,5m. It was taken measurements of transpiration from load cells weighting lysimeter, global, diffuse and PAR radiation, wind velocity, temperature and actual vapor pressure and canopy temperature. Also was taken measurements of leaf area index, height and diameter of plant. The model was test after calibration with experimental data. The model didn’t estimate precisely the components of energy balance, but it was capable to follow the variation of measured data in different proportion and indicating the necessity of better calibration, especially concerned with extinction coefficients of the canopy. The modeling allowed verifying approach limitations founded in literature and used in present model, like the determination of aerodynamic and stomatal resistances.
188

Identificação de raças de Xanthomonas spp. patogênicas a pimentão no estado de São Paulo. / Identification of Races of Xanthomonas spp. pathogenic on pepper in São Paulo State, Brazil.

Wierzbicki, Robert 24 January 2005 (has links)
A pústula bacteriana é uma das principais doenças que afetam o pimentão em todo o mundo. Seu agente causal pode ser disseminado por sementes, e é capaz de diminuir a produção e depreciar os frutos para comercialização. A bactéria Xanthomonas spp., o agente causal da doença, apresenta alta variabilidade. Três espécies estão associadas à doença: Xanthomonas axonopodis pv. vesicatoria, X. vesicatoria e X. gardneri. Enquanto alguns isolados infectam somente o pimentão, outros infectam pimentão e tomate. Xanthomonas axonopodis pv. vesicatoria é considerada a espécie mais comum em pimentão, e era anteriormente conhecida como o grupo A de Xanthomonas campestris pv. vesicatoria (A1 não amidolítico, A2 amidolítico); e o grupo B era representado por Xanthomonas vesicatoria (fortemente amidolítico). Até agora, 11 raças do patógeno foram relatadas, sendo as raças 1, 2 e 3 as mais comuns. A resistência genética tem sido a mais importante forma de controle e pode ser obtida pelo emprego de 4 genes dominantes (Bs1, Bs2, Bs3, Bs4). Estes genes estão associados à reação de hipersensibilidade e representam a forma mais promissora de resistência atualmente. Mesmo assim, o gene de resistência a ser utilizado depende da correta identificação das raças no campo. Este trabalho teve como objetivo a identificação de raças de Xanthomonas spp. isoladas em áreas de produção no Estado de São Paulo, visando o desenvolvimento e/ ou recomendação de cultivares resistentes. A identificação de raças do patógeno foi realizada através da observação da reação de hipersensibilidade em linhas quase isogênicas de pimentão Early California Wonder - ECW, ECW-10R, ECW-20R, ECW-30R; e na pimenta PI-235047. Os resultados obtidos entre os 41 isolados avaliados, indicaram a ocorrência das seguintes raças por região: raça 0 (Lins); raça 1 (Bacuriti); raça 2 (Bragança Paulista, Bacuriti, Lins, Ibiúna, Piacatu e Guaíra); raça 3 (Piedade); raça 7 (Mogi das Cruzes) e raça 8 (Piedade, Bragança Paulista, Bacuriti, Lins e Mogi das Cruzes). Pelos resultados, sugere-se o desenvolvimento e a recomendação de cultivares com o gene Bs2 para as regiões estudadas, pois este gene confere resistência às raças 0, 1, 2, 3, 7 e 8 do patógeno. / Bacterial spot is one of the main diseases that affects the pepper worldwide. Its causal agent can be spreaded by seeds, and it is able to decrease the production and to depreciate fruits for commercialization. The bacteria Xanthomonas spp. the causal agent of bacterial spot is highly variable. Three species are associated to the disease: Xanthomonas axonopodis pv. vesicatoria, X. vesicatoria and X. gardneri. Some isolates infect only pepper and other infect pepper and tomato. Xanthomonas axonopodis pv. vesicatoria has been considered the most common species in pepper, and was formerly known as group A of Xanthomonas campestris pv. vesicatoria (A1 non amylolitic, A2 amylolitic) and group B represented by Xanthomonas vesicatoria (strongly amylolitic). Up to now 11 races of the pathogen have been reported and the races 1, 2 and 3 are the most common. The genetic resistance has been the most important control method, through 4 dominant genes (Bs1, Bs2, Bs3, Bs4). These genes are associated to the hipersensitivity reaction and represent the most promising form of resistance nowadays. Even so, the resistance gene to be used depends on the correct identification of the races in the field. This work aimed the identification of the Xanthomonas spp. races in the São Paulo State from production areas, for the development and/ or recommendation of resistant cultivars. The identification of races of the pathogen was accomplished through the observation of the hypersensitivity reaction on near isogenic lines of Early California Wonder pepper - ECW, ECW-10R, ECW-20R, ECW-30R; and in the PI-235047 hot-pepper. Obtained results from 41 isolates, indicated the occurrence of the next races per region: race 0 (Lins); race 1 (Bacuriti); race 2 (Bragança Paulista, Bacuriti, Lins, Ibiúna, Piacatu and Guaíra); race 3 (Piedade); race 7 (Mogi das Cruzes); and race 8 (Piedade, Bragança Paulista, Bacuriti, Lins, Mogi das Cruzes). The results suggest the development and/ or recomendation of cultivars carring the Bs2 gene for studied regions, which confers resistance to 0, 1, 2, 3, 7, and 8 races of the pathogen.
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Caracterização química e estabilidade oxidativa de produto reestruturado de frango sob ação de embalagem ativa adicionada de extratos de resíduos agroindustriais / Chemical and oxidative stability of restructured chicken product stored under active packaging with addition of agro-industrial residues extracts

Leon, Juan Sebastian Serrano 13 July 2015 (has links)
A qualidade, aceitabilidade e a vida útil da carne de frango e principalmente seus produtos industrializados, dependem de vários fatores, sendo a oxidação lipídica um dos principais problemas de estabilidade do produto. O crescimento da tendência de consumo de compostos naturais por parte da população mundial e a demanda das indústrias de alimentos para controle da oxidação lipídica, surge como alternativa muito promissora a utilização de antioxidantes naturais. O Brasil, com uma grande produção de produtos vegetais e a economia fortemente baseada na agroindústria gera grandes quantidades de resíduos vegetais, sendo os resíduos de película de amendoim e pimenta-rosa potenciais fontes de antioxidantes. Estes resultados confirmados conforme ensaios preliminares in vitro, uma vez que são ricos em compostos bioativos, como compostos fenólicos. Além disto, a quitosana apresenta-se como uma boa matriz para incorporação de extratos contendo compostos bioativos, além de ter capacidade de formar filmes. Assim, o objetivo do estudo foi desenvolver filmes de quitosana com incorporação de antioxidantes naturais a partir dos extratos de resíduos de película de amendoim e pimenta rosa, e avaliar seu efeito sobre a oxidação lipídica em produto reestruturado de frango. O estudo foi dividido em três etapas: a primeira foi utilização da metodologia de superfície de resposta para determinação de uma concentração ótima de extrato de resíduo agroindustrial que incorporado ao filme de quitosana promova inibição da oxidação lipídica (valor de sustâncias reativas ao ácido tiobarbitúrico, TBARS). Na segunda etapa, foi avaliada a incorporação da concentração ótima dos extratos diretamente na carne e nos filmes ativos de quitosana, sobre as características físico-químicas (pH, cor instrumental, índice de peróxidos, e valor de TBARS) e microbiológicas dos tratamentos. Na terceira etapa foram avaliadas as características sensoriais e de aceitabilidade dos tratamentos que apresentaram menor oxidação lipídica. Os resultados revelaram que, na primeira etapa foram otimizadas as concentrações dos extratos de resíduos nos filmes ativos de quitosana. Os teores otimizados foram 80 mg de compostos fenólicos totais (CFT) / kg de carne para os resíduos de película de amendoim e de 90 mg CFT / kg de carne para pimenta rosa. Na segunda etapa, ao final do tempo de armazenamento, pode-se observar que não houve diferença significativa (p > 0,05) para os parâmetros de cor, pH e contagem de mesófilos totais. Para oxidação lipídica, todos os tratamentos apresentaram diferença significativa (p < 0,05), quando comparados com o controle. Para contagem de micro-organismos psicrotróficos totais houve diferença significativa para os tratamentos com filme ativo + extratos, quando comparados com os demais tratamentos. Na terceira etapa, os resultados mostraram que não houve diferença significativa na aceitabilidade entre os tratamentos. Adicionalmente também foi realizada uma caracterização sensorial com consumidores usando a metodologia Check-all-that-apply (CATA). Assim pode-se concluir que foram desenvolvidos filmes ativos de quitosana com adição de extratos de resíduos agroindustriais, com exelente potencial na atividade antioxidante e antimicrobiana em produtos carneos, sem influenciar na aceitabilidade sensorial. / Quality, accessibility, shelf life of chicken meat and mainly of its processed products depends on several factors, wherein lipid oxidation is a major stability product problem. The growth of the consumption trend of natural compounds by the world\'s population, and the demand from the food industry to control lipid oxidation appear as a very promising alternative to the use of natural antioxidants. Brazil, with a large production plant products and a strong economy based on agro-industry generates large amounts of crop residues where peanut shells and pink pepper residues are potential sources of antioxidants. According to preliminary in-vitro tests of these residues, these are rich in bioactive substances such as phenolic compounds. Moreover, chitosan presents itself as a good matrix for incorporation of extracts containing bioactive compounds, in addition to having the ability to form films. The aim of this study was to develop chitosan films incorporating natural antioxidants from peanut shells and pink pepper residues extracts, as well as to evaluate their effect on the lipid oxidation of a chicken restructured product. The study was divided into three stages: first was the use of response surface methodology to determine an optimal concentration of agro-industrial waste extract, which was incorporated into the chitosan film to promote inhibition of lipid oxidation (as an amount of reactive substances to thiobarbituric acid, TBARS). The second stage evaluated the incorporation of this optimal concentration of extracts applied directly in both the meat and the chitosan active films, in relation to the physicalchemical (pH parameters, instrumental color, peroxide value, and TBARS value) and microbiological characteristics of the treatments. The third stage evaluated the sensory characteristics and acceptability of treatments that had a lower lipid oxidation. The results revealed that the first stage optimized the concentrations of extracts from residues into the active chitosan films. The optimized concentration was 80 mg of total phenolic content (TPC) / kg of meat for peanut shells residue extract, and 90 TPC mg / kg of meat for the pink pepper extract. On the second stage, at the end of the storage time, it can be seen that there was no significant difference (p > 0.05) in parameters like color, pH and total mesophylls counts. For the lipid oxidation parameters, all treatments showed significant differences (p < 0.05) when compared with the control treatment. The microbial count of total psychrotrophic microorganisms showed significant differences for treatments with active films + residues extracts when compared with the other treatments. In the third stage, the results showed no significant difference in acceptability between treatments. Additionally, a sensory characterization with consumers using the Check-all-thatapply (CATA) methodology was also performed. Thus, it was concluded that the development of active chitosan films incorporated with extracts of agro-industrial waste was possible, which possess an antioxidant and antimicrobial potential activity without altering the sensory acceptability of the final product.
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Avaliação dos óleos essenciais de plantas nativas da Mata Atlântica como promotores de permeação cutânea / Evaluation of essential oils of plants native to the Atlantic Forest as skin permeation enhancers

Lacerda, Aurea Cristina Lemos 09 October 2014 (has links)
Os óleos essenciais da Pimenta pseudocaryophyllus (Gomes) Landrum de planta de populações naturais de três ecossistemas, localizados na Ilha de Cananéia, região de restinga, no Morro da Cataia, cidade de Cajati, região de encosta, ambas em área de Mata Atlântica, e na Reserva Natural Morro Grande, cidade de Caldas, região de campos montanos, foram avaliados como promotores de permeação cutânea do diclofenaco de potássio. Os óleos essenciais foram extraídos de partes aéreas das plantas e o rendimento do processo foi entre 0,90% (p/p) e 2,7% (p/p). A análise da composição química mostrou diferenças, indicando tratar-se de três quimiotipos diferentes. A interação dos óleos essenciais e dos componentes majoritários com membrana biológica natural foi avaliada por FT-Raman e ATR- FTIR, indicando a interação com as porções lipídicas do tecido. Foram desenvolvidas seis membranas biológicas artificiais, compostas por ceramidas, ácidos graxos e colesterol em proporções equimolares, que foram caracterizadas por espectroscopia Raman confocal e foram consideradas semelhantes. As membranas foram utilizadas no desenvolvimento do sistema PAMPA (Parallel Artificial Membrane Permeability Assay) para avaliar a segurança e eficácia dos óleos essenciais e componentes majoritário como promotores de permeação do diclofenaco de potássio. Os resultados dos ensaios com o sistema PAMPA foram estatisticamente avaliados. A segurança foi avaliada com o critério de permeação mínima dos óleos através das membranas do sistema PAMPA, verificada pela absorbância mínima do eugenol na solução aceptora. Os óleos essenciais e componentes majoritários foram utilizados no pré-tratamento das membranas, nas concentrações de 0,125%, 0,25%, 0,50% e 2,00% (v/v) em etano!. Ensaios de permeação do diclofenaco de potássio no sistema PAMPA indicaram efeito de promoção da permeação para todos os compostos avaliados. O método de doseamento do fármaco por UV foi validado e utilizado para os ensaios de permeação de formulações de gel em base aquosa contendo o diclofenaco de potássio (1,0% p/p). As amostras de gel foram preparadas com o óleo procedente de Morro Grande, selecionado na etapa de avaliação de segurança, a 0,125% (p/v). Adicionalmente, foram preparadas formulações com citronelol e etanol, na mesma concentração. O óleo essencial da Reserva Natural Morro Grande teve efeito de promoção da permeação superior ao do citronelol e etanol, que foram equivalentes. / The essential oils of the species Pimenta pseudocaryophyllus (Gomes) Landrum collected from natural populations of three existing ecosystems in the Cananéia Island, located at sea level, Cajati city, located in hillside region, both in the Atlantic Forest areas, as well as species collected in the Morro Grande Natural Reserve, region of montane fields, were evaluated as skin permeation enhancers of potassium diclofenac. Essential oils were extracted from the aerial parts of the plants and the process yield was between of 0.90% (w/w) and 2.7% (w/w). The chemical composition analysis showed differences between the plants of three origins, indicating that they are different chemotypes. The interaction of the essential oils and their major components with natural biological membrane was evaluated by FT- Raman and ATR-FTIR, indicating interaction with the Iipid portions of the natural membrane. Six artificial biological membranes have been developed, consisting of ceramides, cholesterol and fatty acids in equimolar proportions, which were characterized by confocal Raman spectroscopy and found to be similar. The membranes were used in developing the PAMPA (Parallel Artificial Membrane Permeability Assay) system to evaluate the safety of the potential permeation enhancers. The test results with PAMPA system were statistically evaluated. Safety was evaluated with the criterion of minimum permeation of the essential oil through the membranes, checked by the minimum absorbance of eugenol in the acceptor solution. The essential oils and the major components were used in the pretreatment of the membranes, at concentrations of 0.125%, 0.25%, 0.50% and 2.00% (v/v) in ethanol. Results indicated permeation enhancement effect for ali compounds evaluated. The analytical method for the quantification of potassium diclofenac was validated and used for the evaluation of the permeation of aqueous based gel formulations containing potassium diclofenac (1.0% w/w). The gel samples were prepared with the oil from Morro Grande Natural Reserve, selected in the safety evaluation step, at 0.125% (w/v). In addition, formulations were prepared with citronellol and ethanol at the same concentration. The essential Gil of Morro Grande Natural Reserve was more efficient as permeation enhancer than citronellol and ethanol under the test conditions.

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