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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.
591

Diversité des arbres et résistance des forêts aux invasions biologiques : application au chataignier et son complexe de bioagresseurs exotiques, chancre (Cryphonectria parasitica) et cynips (Dryocosmus Kuriphilus) / Tree biodiversity and forest resistance to biological invasions : application on chestnut and its exotic pest complex, chestnut blight (Cryponectria parasitica) and Asian chestnut gall wasp (Dryocosmus Kuriphilus)

Fernandez-Conradi, Pilar 20 December 2017 (has links)
Les plantes sont au centre d’une grande diversité d’interactions biotiques entre organismes plus ou moins proches qui les exploitent en tant que ressources. L’objectif de cette thèse a été de comprendre comment les infections fongiques de la plante et la diversité des arbres en forêt modifient les interactions arbres-insectes. Nous avons tout d’abord effectué une méta-analyse pour poser le cadre théorique des effets indirects des infections fongiques sur les insectes herbivores associés aux mêmes plantes hôtes. L'effet de l’infection préalable des plantes par les champignons sur les préférences et performances des insectes s’avère généralement négatif. Cependant, la magnitude de cet effet délétère varie selon le mode de vie du champignon, la guilde trophique de l’insecte et la spatialité des interactions (interactions locales vs distantes). Nous avons ensuite analysé de façon empirique les interactions tripartites entre le châtaignier européen (Castanea sativa) et deux de ses bioagresseurs exotiques: le cynips (Dryocosmus kuriphilus), insecte galligène, et Cryphonectria parasitica, champignon pathogène responsable de la maladie du chancre. L'effet sur les taux d’infestation par le cynips de la composition spécifique en essences forestières des forêts de châtaigniers atteintes de chancre a été également étudié. Afin d'identifier les mécanismes sous-jacents aux effets de la diversité des forêts sur cet insecte invasif, les communautés d'insectes parasitoïdes et de champignons endophytes présents dans les galles ont été décrites. Les taux d’infection par le cynips étaient plus faibles dans les mélanges de châtaignier avec du chêne et du frêne que dans des parcelles de châtaignier monospécifiques ou dans les mélanges avec du pin. La composition des forêts influence aussi la composition des communautés de parasitoïdes associés aux galles du cynips mais pas leur abondance, richesse ou diversité. Les communautés de champignons endophytes des galles, étudiées par des méthodes de séquençage de nouvelle génération, sont indépendantes de la composition forestière. Par contre, celles présentes dans les galles différent fortement de celles des tissus foliaires adjacents. Nous avons ainsi apporté de nouvelles preuves que la diversité des plantes et les champignons pathogènes sont des facteurs clés déterminant les interactions plantes-insectes. Etudier comment les plantes interagissent avec leurs insectes et champignons associés, et les mécanismes sous-jacents à l’effet de la diversité des plantes sur ces interactions, doit permettre de mieux comprendre les relations entre diversité et fonctionnement des écosystèmes et de proposer des applications pour la gestion des bio-agresseurs forestiers natifs et exotiques. / Plants are the playground of a large diversity of biotic interactions between related and unrelated organisms exploiting them as common resources. The aim of this thesis was to understand how plant-insect interactions vary with fungal infection of their host plant and plant diversity. I first performed a meta-analysis to provide a theoretical background for plant-mediated effects of fungal infection on herbivorous insects. Overall, I found a negative plant-mediated effect of fungi on both insect preference and performance. However, this effect varied according to fungus lifestyle, insect feeding guild and spatial location of the interactions (local vs distant). Then I experimentally tested plant-fungus-insect tripartite interactions in the particular case of exotic bio-aggressors of the European chestnut (Castanea sativa): the Asian chestnut Gall Wasp (ACGW, Dryocosmus kuriphilus), and the fungal pathogen Cryphonectria parasitica, the causal agent of chestnut blight. I performed an observational study, in natural chestnut forest stands in Italy, where I tested how ACGW infestation rates vary with the tree species composition. I also investigated the mechanisms underlying plant diversity effects on the invasive pest, with a particular focus on its natural enemies such as insect parasitoids and endophytic fungi. ACGW infestation rates was lower in oak and ash chestnut mixtures compared to monocultures or pine-chestnut mixtures. Plot composition also influenced ACGW parasitoid community composition but not their abundances, diversity or richness. Endophytic communities of galls, described by using next generation sequencing methods, did not vary with plot composition. However, they strongly differed from surrounding leaf tissues. We thus provided evidence that plant diversity and fungal pathogens are key drivers of plant-insect interactions. Understanding how plants interact with associated insects and fungi, and mechanisms underlying plant diversity effect on these interactions, will improve our knowledge on diversity-ecosystem functioning relationships and will have practical applications for the management of native and exotic forest pests.
592

Doença meningocócica invasiva nas capitais da Região Sul do Brasil: características e tendências / Invasive meningococcal disease in the capitals of the Southern Region of Brazil: characteristics and trends

Masuda, Eliana Tiemi 21 May 2018 (has links)
Objetivos: Analisar a tendência, descrever mudanças no comportamento da doença meningocócica invasiva (DMI) e estimar o impacto da vacina conjugada do meningococo C (VCMC) nas capitais da região Sul do Brasil, no período de 1991 a 2015, assim como, investigar as características sociodemográficas, econômicas e de intervenções tecnológicas associadas aos casos pertencentes a cluster da doença no município de Curitiba (PR), no período de 2001 a 2014. Métodos: As áreas de estudo englobaram as capitais da Região Sul do Brasil: Curitiba (PR), Florianópolis (SC) e Porto Alegre (RS), a população de estudo abrangeu os casos de DMI notificados entre 1991 a 2015 à vigilância da doença e residentes nessas capitais. A definição de caso adotada foi a padronizada pelo Ministério da Saúde. As fontes de dados foram: vigilância da DMI, o Instituto Adolfo Lutz, o Instituto Brasileiro de Geografia e Estatística e o Instituto de Pesquisa e Planejamento Urbano de Curitiba. A tendência da incidência e mortalidade da DMI foi determinada pelo modelo de regressão polinomial. A intensidade e a direção da relação linear entre a taxa de incidência e os indicadores socioeconômicos, de saúde e sorogrupo foram analisadas pelo coeficiente de correlação de Pearson. O impacto da VCMC foi estimado pela Fração Prevenida na População, comparando as taxas de incidência de 2012 e 2015 com as de 2009. Investigou-se os potenciais fatores associados a casos pertencentes a cluster no período de 2001 a 2014 por meio das estimativas de odds ratio não ajustada e ajustadas pela regressão logística múltipla não condicional, com os respectivos intervalos de confiança de 95%. Resultados: No período de estudo, a DMI apresentou três comportamentos distintos nas capitais da região sul: i) epidêmico na década de 1990, ii) declínio das taxas na década de 2000, antes da introdução da VCMC na rotina de imunização e, iii) estacionário com taxas baixas entre 2011 e 2015, sob a influência da VCMC. Observamos nesses períodos a influência de fatores biológicos, socioeconômicos e de saúde na incidência dessas capitais. No estudo mais detalhado em Curitiba, apresentou-se associado aos casos pertencentes a cluster, ajustados no tempo e pela idade, residir em bairros de baixa renda (OR: 2,3, IC95%:1,1-4,5). O sorogrupo predominante foi o B com 65,4%, seguida pelo C com 24,5% e 8,3% pelo W. Possivelmente, em virtude da baixa incidência do sorogrupo C, não se verificou a redução na incidência total da DMI, nestas capitais. Entretanto, no período posterior a VCMC, os casos pelo sorogrupo C foram raros ou zerados na faixa etária destinada a vacinação em Curitiba e Florianópolis. Em Porto Alegre foram registrados casos pelo sorogrupo C na faixa etária vacinada e o sorogrupo W se destacou. Conclusão: A partir do início desse século houve declínio expressivo da incidência da DMI nas capitais da região Sul do país, antes mesmo da introdução da vacina, aproximando-se das taxas de DMI encontradas em países de elevada renda. Tais resultados são consistentes, com trabalhos que mostram uma associação da DMI com as condições de vida e grau de desenvolvimento das populações. / Objectives: To analyze the trend and describe changes in the epidemiology of invasive meningococcal disease (IMD) and to estimate the impact of the meningococcal conjugate C vaccine (MCCV) in the capitals of the southern region of Brazil, from 1991 to 2015, as well as to investigate the sociodemographic, economic and technological interventions associated to the cases belonging in cluster of the disease in the city of Curitiba (PR), from 2001 to 2014. Methods: The study areas included the capitals of the States of Southern Brazil: Curitiba (PR), Florianópolis (SC) and Porto Alegre (RS), the study population considered cases of IMD reported between 1991 and 2015 to surveillance and residents in these capitals. The IMD case definition adopted was that standardized by the Ministry of Health. The data sources were the surveillance of the IMD, the Adolfo Lutz Institute, the Brazilian Institute of Geography and Statistics and the Institute of Research and Urban Planning of Curitiba. The trend of IMD incidence and mortality was determined by the polynomial regression model. The intensity and direction of the linear relationship between the incidence rate and socioeconomic indicators, health and serogroup were analyzed by the Pearson correlation coefficient. The impact of the MCCV was estimated by the Prevented Fraction for the Population comparing the incidence rates of 2012 and 2015 with those of 2009. We investigated the potential factors associated with cases belonging in cluster between 2001 and 2014 by the unadjusted and adjusted odds ratio estimates by the multiple unconditional logistic regression, with the respectives confidence intervals of 95%. Results: Between 1991 and 2015, IMD presented three distinct periods in the capitals of the southern region: i) epidemic in the 1990s, ii) decline in rates from 2000 to 2010, before the introduction of MCCV in immunization routine and (iii) stationary at low rates in 2011 to 2015, under the influence of MCCV. In this period, we observed the influence of biological, socioeconomic and health factors on the incidence of these capitals. In more detailed study in Curitiba, it was associated with cases belonging in cluster, adjusted in time and by age, to live in low-income neighborhoods (OR: 2.3, 95% CI: 1.1-4.5). Serogroup B was predominant with 65,4%, followed by C with 24,5% and 8,3% by W. Possibly, due to the low incidence of serogroup C, there was no reduction in the total incidence of IMD in these capitals. However, *in the period after MCCV, serogroup C cases were rare or zero in the age group destinedfor vaccination in Curitiba and Florianópolis. In Porto Alegre, cases were registered by serogroup C in the vaccinated age group and serogroup W was relevant. Conclusion: From the beginning of this century there was a significant decline in the incidence of IMD in the capitals of the southern region of the country, even before the introduction of the vaccine, approaching IMD rates found in high income countries. These results are consistent, with studies showing an association of IMD with living conditions and the degree of population development.
593

Uma abordagem filogeográfica da espécie invasora Drosophila suzukii (Diptera: Drosophilidae) no Brasil / A phylogeographic approach to the Drosophila suzukii (Diptera: Drosophilidae) invasion in Brazil

Abreu, Petra Ferronato Gomes de 19 June 2018 (has links)
As invasões biológicas tem alcançado ampla disseminação devido a ações antrópicas em todo o planeta. Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), é uma espécie invasora global que vem promovendo grandes danos às culturas agrícolas. Nativa do Sudeste Asiático, D. suzukii recentemente (ano de 2013) invadiu e se dispersou pela América do Sul. Aqui, utilizamos uma abordagem filogeográfica baseada no fragmento do gene COI para explorar a dinâmica de invasão das populações de D. suzukii no Brasil. Identificamos cinco haplotipos e uma diversidade genética moderada nas populações brasileiras, que estão em expansão demográfica e espacial. A AMOVA indicou uma alta estrutura genética entre as populações, o que é parcialmente explicado pela sua origem morfoclimática e história de invasão. D. suzukii expandiu do sul para o sudeste do Brasil, auxiliado pelo transporte de frutas mediado por humanos de região para região. O compartilhamento de haplótipos entre as regiões brasileiras e outras regiões invadidas do mundo sugere um único evento de invasão de D. suzukii no Brasil, originário de áreas previamente invadidas (como América do Norte e Europa). A rápida dispersão geográfica e a grande variedade de frutas atacadas por D. suzukii requerem implementação imediata de estratégias de controle (legais e fitossanitárias) para gerenciar esta praga no Brasil. / Biological invasions have reached large parts of the globe, due to human actions across the planet. Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) is a globally invasive species, always associated with enormous and costly damage to agricultural crops. Native to Southeast Asia, D. suzukii recently (i.e. 2013) invaded and is dispersing through South America. Here, we used a phylogeographic approach based on the COI gene fragment to explore the invasion dynamics of D. suzukii populations in Brazil. We identified five haplotypes and moderate genetic diversity in Brazilian populations, which are undergoing demographic and spatial expansion. The AMOVA indicated a high genetic structure among the populations, which is partially explained by their morphoclimatic origin and invasion history. D. suzukii expanded from southern to southeastern Brazil, aided by human-mediated transport of fruits from region to region. The sharing of haplotypes among Brazilian and other invaded regions of the world suggests a single invasion event of D. suzukii in Brazil, originating from previously invaded areas (e.g., North America and Europe). The rapid geographic dispersal and wide variety of fruits attacked by of D. suzukii require immediate implementation of control strategies (legal and phytosanitary) to manage this pest in Brazil.
594

Ocorrência e Distribuição de Achatina fulica e sua Importância como Hospedeiro de Nematoides na Cidade de Palmas, Estado do Tocantins, Brasil

Cardoso, Cerize Rodrigues Lima 15 December 2017 (has links)
O caramujo africano ou caramujo gigante, Achatina fulica, é considerado uma das cem piores espécies invasoras do mundo, causando prejuízos ambientais, econômicos e à saúde humana e animal, sendo relatado como hospedeiro intermediário de nematoides. Este estudo teve por objetivo descrever a distribuição do caramujo em Palmas, Tocantins, e pesquisar a ocorrência das larvas de nematoides, considerando os fatores climáticos da região. No período de outubro de 2014 a março de 2017 foram coletados 380 caramujos em hortas comunitárias e lotes baldios. Os caramujos foram identificados e processados por digestão. Os helmintos recuperados foram identificados morfologicamente. Foram encontradas larvas de Aelurostrongylus abstrusus nos caramujos provenientes de 35,6% dos terrenos baldios estudados e também a forma adulta de Rhabditis sp, em 7,14% dos lotes baldios. Foi possível observar que o local da coleta dos caramujos influenciou na presença de larvas de nematoides. Durante o estudo, as condições climáticas foram evidenciadas pela baixa umidade e altas temperaturas, podendo ter influenciado na ocorrência de caramujos, durante o período analisado, visto que estes costumam enterrar-se e estivar em condições desfavoráveis de temperatura e umidade. Este estudo demonstra a ocorrência do caramujo em diversas regiões da cidade de Palmas e seu papel como hospedeiro de nematoides, o que evidencia a necessidade de medidas de controle e vigilância epidemiológica para zoonoses transmitidas por este caramujo. / The African snail or giant snail, Achatina fulica, is considered one of the hundred worst invasive species in the world, causing environmental, economic and human health damage, being reported as an intermediate host of nematodes. This study was intended to describe the distribution of the snail in Palmas, Tocantins, and to research the occurrence of the larvae of nematodes, considering the climatic factors of the region. In the period from October 2014 to March 2017, 380 snails were collected in community gardens and vacant lots. The snails were identified and processed by digestion. The helminth recovered have been identified morphologically. Larvae of Aelurostrongylus abstrusus were found in snails from 35.6% of the studied vacant land and also the adult form of Rhabditis sp, in 7.14% of the vacant lots. It was possible to observe that the site of the collection of snails influenced in the presence of larvae of nematodes. During the study, the climatic conditions were evidenced by low humidity and high temperatures, may have influenced the occurrence of snails during the analyzed period, since they usually bury themselves and stowed in unfavorable conditions of temperature and Moisture. This study demonstrates the occurrence of the snail in several regions of the city of Palmas and its role as host of nematodes, which shows the need for measures of control and epidemiological surveillance for zoonoses transmitted by this snail.
595

Sjuksköterskors erfarenheter av att leda omvårdnad för personer med ventilatorbehandling via trakeostomi : inom kommunal hemsjukvård / Nurses' experiences of nursing leadership for people with invasive ventilator treatment : in community home care.

Möller, Ann-Katrin, Larsen, Maria January 2018 (has links)
Background: More and more people in need of hospital care can today be cared for in their homes. This has led to that more and more people nowadays can be treated with an invasive mechanical ventilator in their homes. This fact has placed great demands on the nurse who is responsible for and leads nursing.  Aim: The aim was to describe nurses’ experiences of nursing leadership in community home care for people with invasive ventilator treatment. Method: The study had a qualitative approach. Eight nurses and two district nurses working in community home care in two different municipalities participated in the study. Data were collected through semi-structured interviews and analysed by qualitative content analysis. Results: Three categories and nine subcategories emerged. The first category; Equip oneself and the nursing staff for the task, with the subcategories; Creating a feeling of safety and Tutoring nursing staff. The second category; Lead the nursing in someone's home is a balance, with the subcategories; Not given access from the patient and Involving the patient and close associates. The third category; A complex challenge for the nurse, with the subcategories; Big responsibility to delegate, Lead nursing staff are time consuming, Lack in organizational conditions; Keep in mind all threads and Not feeling safe.  Conclusion: For the nurse it is a complex task to lead in nursing leadership in community home care for people with invasive ventilator treatment. Important requirements are placed on the nurse’s knowledge and skills. Lacks are found in organizational conditions. / Idag har allt fler personer som tidigare behövde sjukhusvård möjlighet att vårdas i sina hem, även då de är beroende av avancerad teknik. Detta ställer ökade krav på sjuksköterskors kompetens i hemsjukvård. I den här studien var avsikten att undersöka sjuksköterskors erfarenheter av att leda omvårdnad i kommunal hemsjukvård för personer med ventilatorvård via trakeostomi. Intervjuer gjordes med 10 sjuksköterskor vilka ansvarar för vården av personer med behov av andningshjälp via ventilator i hemmet. Vid intervjuerna efterfrågades sjuksköterskornas erfarenheter av att leda omvårdnad för dessa personer. Ur analys av intervjuerna framkom att sjuksköterskorna tyckte att det var en utmanande uppgift att leda omvårdnad för dessa personer. En stor och tidskrävande uppgift som sjuksköterskorna ansvarar för är att lära den övriga personalen som hjälper personen i hemmet att sköta omvårdnad och teknisk utrustning så som ventilator. Sjuksköterskorna upplevde att de fick för lite stöd från sjukhusets sida och från sin arbetsgivare. Många av sjuksköterskorna tyckte att de själva hade för lite praktisk erfarenhet av att sköta den tekniska utrustningen vilket försvårade i uppgiften att leda omvårdnad. Det skiljer sig mycket mellan vård på sjukhus och i hemmet. I hemmet var sjuksköterskorna ofta mer ensamma i sina beslut. Det fanns ingen annan i närheten att fråga. Många av sjuksköterskorna upplevde att det var roligt och utvecklande att leda omvårdnad för dessa personer med stora vårdbehov. De ansåg dock att denna typ av avancerad vård behöver organiseras bättre för att sjuksköterskorna ska kunna utföra sina arbetsuppgifter på ett tryggt och säkert sätt. Det som idag anses problematiskt behöver ses över. Detta eftersom det troligtvis kommer behövas ännu mer av denna typ av avancerad vård i hemmen i framtiden, då allt fler svårt sjuka har möjlighet att få vård i sina hem. Genom studien framkom viktig kunskap för att kunna fördela resurser och planera för en välfungerande organisation, god kompetens och säkerhet i vården. Kunskaper som chefer och politiker, vilka har beslutsfattande position skulle kunna ha användning av. Utifrån denna studies resultat kan förbättringsområden identifieras och motivera till förändringsarbete i verksamheter där denna typ av vård förekommer.
596

Caça legal como forma de controle de uma população invasora de javali na Floresta Nacional de Capão Bonito, São Paulo, Brasil / Legal hunting as a control mechanism of an invasive wild boar population in Capao Bonito National Forest, Sao Paulo, Brazil

Rodriguez, Catalina Zuluaga 20 October 2015 (has links)
Espécies invasoras apresentam características vantajosas sobre espécies nativas o que pode torná-las uma das principais ameaças à biodiversidade. O javali (Sus scrofa), é considerado uma das piores espécies invasoras no mundo devido ao alto impacto que causa nos ecossistemas naturais. A caça é a estratégia de controle mais usada, sendo sua efetividade variável. Determinar a efetividade de uma estratégia de controle num local específico implica estudar as características da população invasora assim como a pressão de caça nela exercida. Nesse contexto, este estudo tem por objetivo avaliar a caça legal como forma de controle da população de javalis na Floresta Nacional (FLONA) de Capão Bonito no estado de São Paulo, Brasil. Foram utilizadas armadilhas fotográficas para estimar o tamanho dos grupos de javalis, assim como levantadas informações de presença de javalis por detecção de vestígios ao longo da área de estudo. Características da população foram obtidas a partir dos indivíduos abatidos e de literatura. A intensidade da caça foi informada pelo caçador e vizinhos da FLONA forneceram informações complementares sobre danos causados pela espécie. Há indícios de diminuição depois da liberação da caça. No entanto, não há evidencia quantitativa suficiente de que o controle esteja sendo efetivo. Imprecisões nas estimativas podem ser diminuídas com estudos específicos das características populacionais e comportamentais ao longo do tempo, além de estudos que possam incluir a magnitude da caça ilegal. / Invasive species have advantageous traits over native species which may turn them into one of the most important threats to biodiversity. Wild boar (Sus scofa) is considered one of the worst invasive species of the world due to the high impact over natural ecosystems. Worldwide, hunting is the most used control strategy with variable efficacy. In order to determine the efficacy of a control strategy it is necessary to evaluate the invasive population traits and the hunting impact. This work aims to studying the legal hunting effectiveness as a control method of wild boar population at the National Forest of Capão Bonito, São Paulo, Brazil. Cameras traps were used to estimate group size and transects were used to detect vestiges in the study area. Population characteristics were obtained from hunted specimens and from literature review. The hunting pressure was informed by the hunter and neighbors provided additional information about damages caused by the species. There is evidence of the wild boar population reduction after the beginning of hunting. However, there are no sufficient quantitative evidence about such impact. The accuracy of the results presented in this work could be improved by the development of further research in population and behavioral characteristics including the potential impact of illegal hunting.
597

Caracterização de linhagens industriais de Saccharomyces cerevisiae quanto a filamentação induzida por álcoois e deficiência de nutrientes / Characterization of industrial strains of Saccharomyces cerevisiae by filamentous growth induced by alcohol and nutrient deprivation

Silva, Paula Cristina da 05 September 2006 (has links)
O uso de microrganismos na biotecnologia tem grande importância e interesse econômico no Brasil. Entre esses microrganismos a levedura Saccharomyces cerevisiae tem grande destaque nos processos fermentativos para produção de pães, bebidas e álcool combustível. Dimorfismo em S. cerevisiae (alteração na morfologia celular de células brotantes para estruturas filamentosas) tem sido observado em condições de deficiência de nitrogênio, carbono e presença de álcoois superiores. Isso pode ser um tipo de defesa da levedura, que ao encontrar um meio prejudicial ao seu desenvolvimento, através da alongação das células, crescimento hifal e da invasão do meio, cria novos mecanismos para encontrar alimento para o seu desenvolvimento. Neste trabalho, dezessete linhagens (haplóides e diplóides) de S. cerevisiae isoladas do processo fermentativo industrial para produção de etanol foram caracterizadas quanto à filamentação induzida por deficiência de carbono (crescimento invasivo), nitrogênio e presença de álcoois superiores, em meio de cultura sólido. Objetivou-se também avaliar a indução da filamentação por álcool isoamílico em condições de fermentação e seus efeitos sobre os parâmetros fermentativos. A maioria das linhagens apresentou filamentação em resposta aos álcoois isoamílico, butanol e isobutanol, não respondendo ao metanol, sendo mais marcante em linhagens haplóides. O álcool isoamílico foi o indutor mais eficiente em meio (YEPD), linhagens diplóides apresentaram crescimento invasivo, embora esse tipo de filamentação seja mais comum em linhagens haplóides. Resultados semelhantes foram observados quando se utilizou frutose e manose em substituição à glicose no meio de cultura. As linhagens não filamentaram em meio de cultura deficiente em nitrogênio (SLAD). A linhagem CCA193 (PE-02), extensivamente utilizada nas destilarias da região, foi escolhida para a indução da filamentação por álcool isoamílico em condições de fermentação (meio de caldo de cana e sistema de reciclo celular). A adição de 0,1% desse álcool superior afetou significativamente os parâmetros fermentativos, induzindo filamentação após o terceiro ciclo fermentativo, coincidindo com a recuperação da viabilidade celular, número de células viáveis, produção de etanol e diminuição do Brix residual, embora não se comparando aos valores alcançados ao final do sexto ciclo no tratamento sem álcool isoamílico. Os resultados obtidos indicaram que a filamentação induzida por álcoois superiores e deficiência de nutrientes (especialmente carbono) é um processo comum em linhagens industriais de S. cerevisiae e pode contribuir para a manutenção/sobrevivência das células em condições adversas. / The use of microorganisms in biotechnology is an important and economical area of interest in Brazil. Among these, the yeast Saccharomyces cerevisiae is specially remarkable in baking industry and alcohol fermentation. Dimorphism in S. cerevisiae (cell morphology alterations from budding cells to filamentous structures) has been observed in conditions of nitrogen and carbon deprivation and presence of fusel alcohoes. This can be a defense mechanism that allows the yeast to forage for nutrients through cell elongation, hyphal growth and medium invasiveness. In this work seventeen industrial strains of S. cerevisiae (haploid and diploid) isolated from the fermentative process for alcohol production were characterized for filamentation induced by carbon (invasive growth) and nitrogen deprivation and presence of fusel alcohol, in solid culture media. The induction of filamentation by isoamyl alcohol in fermentation condition was also aimed, evaluating its effects on the fermentative parameters. The majority presented filamentation induced by isoamyl alcohol, butanol and isobutanol, but not by methanol. The isoamyl alcohol was the most effective inducer in rich medium (YEPD), diploid strains showed invasive growth, although this kind of filamentous growth be common in haploid strains. Similar results were observed when fructose and mannose were utilized replacing glucose in the culture medium. In nitrogen-deficient medium (SLAD) the strains did not filament. The yeast strain CCA193 (PE-02), extensively used in the alcohol units, was chosen for filamentation induction by isoamyl alcohol in fermentation conditions (sugar cane juice medium and cell recycle system). The addition of 0.1% of this higher alcohol affected significantly the fermentative parameters, however filamentation was induced after the third fermentative cycle, coincident with the cell viability, viable cell number, ethanol production recuperation and residual Brix decrease, though the values were not comparable to the treatment without isoamyl alcohol by the sixth cycle.The results obtained indicate that the filamentation induced by higher alcohol and nutrient deprivation (specially carbon) is a common process in industrial strains of S. cerevisiae and can contribute for the cell maintenance/survival in adverse conditions.
598

"Ansiedade e angioplastia coronária transluminal percutânea (ACTP): uma contribuição para a enfermagem" / Anxiety and Percutaneous Transluminal Coronary Angioplasty (PTCA): A contribution to nursing

Ignacio, Daniela Sarreta 28 June 2004 (has links)
Estudo descritivo, desenvolvido por método de estudo de caso, de múltiplos casos, enfocando o fenômeno da ansiedade. Objetivos: identificar a presença e quantificar o nível de ansiedade em cardíacos isquêmicos antes e após, dez minutos, das orientações ao procedimento de angioplastia coronariana transluminal percutânea (ACTP); mensurar o nível de ansiedade desses clientes, dez minutos antes do indivíduo entrar em sala de procedimentos para sua realização, e identificar a presença de sintomas de ansiedade. Aprovado pelo Comitê de Ética em Pesquisa, com coleta de dados realizada por demanda espontânea conforme conveniência do pesquisador. A amostra compôs-se de vinte sujeitos cardíacos isquêmicos, adultos, encaminhados via Sistema Único de Saúde ao primeiro procedimento de ACTP. Composto por observação participativa e três momentos de mensuração da pressão arterial, freqüência cardíaca e respiratória e aplicação do Inventário de Ansiedade Traço–Estado de Spielberger (IDATE) para Estado, no primeiro momento também foi aplicado o IDATE–Traço. Para obtenção dos resultados aplicou-se métodos de análise estatística simples. Os resultados encontrados foram que a pressão arterial sistólica se manteve acima dos valores limites, segundo a Sociedade Brasileira de Cardiologia, nas três etapas em mais de 60% dos casos, sendo realizado o tratamento anti-hipertensivo; os padrões observados para freqüência cardíaca se mantiveram na faixa de normalidade para 85% dos casos, porém, em 70% dos casos faziam-se uso associado de betabloqueadores; a freqüência respiratória mostrou-se ascendente durante o evoluir das etapas, com taquipnéia em 50% dos casos no segundo momento e em 70% no terceiro momento. Os valores, segundo categorização do IDATE, tiveram as médias do estado de ansiedade em faixa moderada nos três momentos, sendo que entre o segundo e terceiro momentos houve variação de, mais ou menos, seis pontos, levando alguns clientes ao nível elevado. Para ansiedade traço a faixa também foi moderada. As orientações de enfermagem realizadas por cinco profissionais diferentes produziu, em 60% dos clientes, aumento da pontuação do IDATE, sendo percebido e relatado por alguns como aumento do nervosismo após as orientações. O conteúdo das observações demonstra que comportamentos característicos à ansiedade foram mantidos em todos os clientes, tendo maior número e variedade sem relação ao tempo de espera. Conclui-se que a ansiedade, provocada pela ACTP, já vem alterada (moderada), mantendo-se ou agravando-se ao longo da espera, e as orientações de enfermagem não produzem a redução da ansiedade, em alguns casos a eleva mais. Mesmo utilizando medicações anti-hipertensivas, os clientes desenvolvem hipertensão leve a severa, acompanhada por elevação da freqüência respiratória e manutenção da freqüência cardíaca na normalidade nos três momentos. O ambiente ao qual o indivíduo é exposto contribui para desencadear ansiedade, agravando-a também. Considera-se a amostra do estudo pequena, permitindo apenas a generalização naturalística. Expôs-se a realidade vivida pelo cardíaco, suscitando novos questionamentos e demonstrando a necessidade de intervenções ambientais locais. Espera-se com este trabalho o desencadear de outros estudos com populações maiores, aprofundando-se na compreensão da ansiedade. / This descriptive study was developed by mens of the case study method, of various cases, focusing the anxiety phenomena. Goals: identify the presence and qualify the level of anxiety in ischemic cardiac patients before and after (ten minutes) giving out instructions about the procedure of the percutaneous transluminal corornary angioplasty (PTCA); measure the level of anxiety of these clients ten minutes before they entered in the procedure room for itscompletion. The Research EthicsCommittee approved this study, and data collection was performed through spontaneous demand according to researcher’s convenience. The sample: considered of twenty ischemic cardiac patients, all adults, which had been forwarded by the Single Health Sistem for the first PTCA proceduce. The study was compound which a structured partivipative observation and three moments for measuring arterial pressure, cardiac and respiratory frequency, and the application of Spielberger’s (STAXI) State-Trait Anxiety Inventory. In the first moment there was also the application of the STAXI-Trait. Methods of simple statistical analisys were used to obtain the results. Results: showed that the sytolic arterial pressure was maintained above limit values, according to the Cardiology Brazilian Society, in all threee moments for more than 60% of the cases, anti-hypertensive treatment was performed; the observed satandarts for cardiac frequency were kept within the normality rank for 85% of the cases, however, 70% of the individuals form the sample made use of beta-blockers; the respiratory frequency showed to rise during the evolutionof the moments. With increased respitation rate in 50% of the cases in the second moment and 70% in the third. The values, according to the score and categorization of STAXI, had the measures of state of anxiety in a moderate rank in the three moments, being that there was a variation between the sencond and third moments of up to approximately six points, whichled some clientsto wrong level. For trait anxiety, the rank was also moderate. The nursing instructions were performed by five different professionals and produced an increase of STAXI pontuaction in 60% of the clients. This was obseved and reported by someas an increase of nervousness after the instruction. The content of the observations shows that the characteristic behaviors related to anxiety were maintained in all clients, with a higher number and variety disproportional to the waiting time. The study allows us to conclude that the anxiety caused by PTCA is already altered (moderate), and is kept at this level or worsens during the waiting period, and the nursisng instructions do not make this anxiety decrease, and, in some cases, it even increase. Despite using anti-hypetensive medication, the clientdevelop slight to severe hypertension accompained by an elevation of respiratory frequency and maintenance of cardiac frequency at normal rates from the first to the third moment. The environment to which the individual is exposed contributes to the manifestation of anxiety, worsening it was well. The study’s sample is considerate to be small, allowing only the naturalistic generalization. The realy experienced by cardiac patient has been exposed, raising new questionings and showing the need for local environmental interventions. It is hoped to, throught this study, incite new studieswith larger populations, increasing the comprehension of anxiety.
599

RECRUITMENT SOURCES OF ASIAN CARPS IN THE OHIO RIVER BASIN

SCHILLER, AARON Lee 01 December 2018 (has links)
Knowledge of natal environments and dispersal of Silver Carp (Hypophthalmichthys molitrix) inhabiting the Ohio River, and Kentucky and Barkley lakes would inform development of strategies to control established and emerging populations. However, the principal natal environments supporting the emerging bigheaded carp population in the Ohio River basin are unknown. There is also a need to assess the role of tributaries as nursery sites to increase understanding of dispersal patterns and better target young fish. The goal of this study was to identify recruitment sources and determine dispersal patterns of Silver Carp in the Ohio River basin using evidence from otolith core trace element compositions relative to ambient water elemental measurements. Fish were collected from the Ohio River, and Kentucky and Barkley lakes from 2014-2017 and water samples were taken during summer 2012-2017. Water samples maintained temporal stability and spatial differentiation for the Ohio River and tributaries during the sampling period. Results suggest that most Silver Carp in the Ohio River are utilizing tributaries during early life. Results also suggest there is passage of carp through the locks into the lakes from the Ohio River and natural reproduction is occurring in or above Kentucky and Barkley lakes. Results will inform development of efforts to target and remove spawning and young bigheaded carps as well as direct management efforts in the Tennessee and Cumberland River systems.
600

Waves of invaders : interactions among invasive species and their impacts on ecosystem structure and functioning

Jackson, Michelle C. January 2012 (has links)
Many freshwater ecosystems sustain several invasive species. Here I examine multiple invasions in two highly invaded and well catalogued catchments; Lake Naivasha, Kenya and River Thames, England. New metrics, derived from stable isotope analysis, are used to provide measures of trophic diversity and to examine dietary interactions among species. I test the hypothesis that functionally similar sympatric species will occupy a smaller niche than their allopatric counterparts. Additionally, I quantify the impact of multiple invasive species on ecosystem structure and functioning in order to address the question; do interactions among species amplify or mitigate one another's impact? In Lake Naivasha, the stable isotope metrics revealed serial replacement of invasive species due to dietary interactions. Invasive red swamp crayfish were eventually excluded from the lake due to niche restriction in the presence of a more recent invader, the common carp. Now, the crayfish have migrated into the catchment where they overlap with a species of native river crab. Here, I found a novel mechanism of invasion, whereby the crayfish restricted their niche at the invasion front in order to reduce competition with crabs. Crayfish also caused significant changes in invertebrate community structure and increased decomposition rates, which indirectly resulted in displacement of the crabs. In the Thames catchment, I catalogue the non-indigenous species and show how invasion rates have increased significantly since 1800 due to globalisation. Using the four species of invasive crayfish present (red swamp, signal, Turkish and virile), I demonstrate their extensive diet plasticity using novel measures of niche width and individual specialisation based on stable isotope data. Interactions among the crayfish were examined and this revealed that each species has varying and independent impacts on invertebrate community structure, algal standing stock and decomposition rates. Hence, interactions among invaders are not expected to amplify or mitigate one another's impact and instead, the combined impact will be the sum of their allopatric impacts.

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