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Avaliação e tratamento da água de lavagem dos filtros e dos resíduos sedimentados gerados pela tecnologia de ciclo completo contendo oocistos de Cryptosporidium spp. e cistos de Giardia spp. / Evaluation and treatment of water treatment plants backwashing water and sedimented residue with Cryptosporidium spp. oocysts and Giardia spp. cystsAllan Pretti Ogura 27 February 2018 (has links)
Os oocistos de Cryptosporidium spp. e os cistos de Giardia spp. podem gerar doenças de veiculação hídrica associadas a problemas de saúde pública. Os (oo)cistos são de difícil remoção e inativação durante o tratamento de água, principalmente devido ao tamanho reduzido e à resistência ao processo de cloração. Além disso, os métodos de detecção de protozoários na água apresentam elevado custo e estão sujeitos à grande variabilidade e à baixa reprodutibilidade, especialmente em águas de elevada turbidez. Com água de estudo com turbidez de aproximadamente 110 uT, ensaios de tratabilidade com cloreto de polialumínio foram feitos em jarteste para a obtenção da água de lavagem dos filtros (ALF) e do resíduo sedimentado. O método escolhido para detecção de (oo)cistos foi a centrifugação direta com adição de solução de dispersão ICN 7X seguido de IMS com duas dissociações ácidas (CD + ICN 7X). O tratamento dos resíduos objetivou a inativação dos (oo)cistos, por meio de danos à estrutura celular dos parasitos, identificada pela incorporação do corante iodeto de propídio no microrganismo. Para o método CD + ICN 7X, menor interferência na viabilidade dos (oo)cistos foi observada em relação à floculação em carbonato de cálcio e melhor recuperação do que a centrifugação direta. O controle de qualidade analítica desse método, feito com suspensão do kit EasySeed®, apresentou recuperação de 2,8±0,8% de oocistos e 7,8±2,9% de cistos para a ALF e de 3,3±2,0% e 24,8±8,0%, para oocistos e cistos no resíduo sedimentado. Apenas a recuperação de cistos de Giardia spp. no resíduo sedimentado atendeu aos padrões recomendados pelo Método 1623.1 da USEPA. A presença de microesferas magnéticas aderidas aos (oo)cistos foi observada nos poços de leitura após a IMS, indicando limitações desse método de purificação. Para o tratamento alcalino do resíduo sedimentado, a dosagem de 27mg/100mL foi testada para os tempos de 3 e 5 dias e, respectivamente, foram obtidos 1,85 e 3,0 log de inativação de oocistos e 2,05 e 2,14 log de inativação para cistos. Para o processo de ozonização da ALF, avaliado apenas para oocistos, as inativações de 2,83 log e 3,44 log foram obtidas para as dosagens de 7,5 mg O3 L-1 por 10 min e 10 mg O3 L-1 por 5 min, respectivamente. / Cryptosporidium spp. oocysts and Giardia spp. cysts are infectious forms and can cause public health problems due to associated waterborne diseases. (Oo)cysts are difficult to remove and inactivate during water treatment, mainly because of reduced size and resistance to chlorination. In addition, protozoan detection methods in water are expensive and subject to high variability and low reproducibility, especially in high turbidity water. In jartest treatability tests, 110 uT study water was treated with polyaluminium chloride to obtain backwashing water (BW) and sedimented residue. The method chosen for detection of (oo)cysts was direct centrifugation with addition of 7X ICN dispersion solution followed by IMS with two acid dissociations. Treatment of residuals objectified inactivation of (oo)cysts by damages on parasites cellular structure, identified by inclusion of propidium iodide as an indicator. The method of detection chosen showed less interference in the viability of (oo)cysts in comparison to flocculation in calcium carbonate and better recovery than direct centrifugation. The analytical quality control of this method, performed with EasySeed® suspension, obtained recovery of 2.8±0.8% oocysts and 7.8±2.9% cysts for BW and of 3.3±2.0% and 24.8±8.0%, for oocysts and cysts in sedimented residue. Only Giardia spp. recovery in sedimented residue complied with the standards recommended by USEPA Method 1623.1. Magnetic microspheres were found attached to (oo)cysts in microscope slides after IMS, indicating limitations of this purification method. For the alkaline treatment of sedimented residue, dosage of 27mg / 100mL was tested for 3 and 5 days and respectively 1.85 and 3.0 log inactivation were obtained for oocysts while 2.05 and 2.14 log of. For ozonation of BW, evaluated only for oocysts, 2.83 log and 3.44 log inactivation were obtained for dosages of 7.5 mg O3 L-1 for 10 min and 10 mg O3 L-1 for 5 min, respectively.
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Influência da infecção por Trypanosoma evansi sobre hormônios do sistema reprodutivo de ratos experimentalmente infectados / Influence of experimental infection with Trypanosoma evansi on reproductive hormones in ratsFaccio, Luciana 04 October 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Infection by Trypanosoma evansi causes various pathological changes in animals, as well as reproductive problems whose pathogenesis is not fully known. Therefore, the objective of this study was to evaluate the serum concentrations of reproductive hormones, histopathology and biomarkers of oxidative stress in testicles of rats experimentally infected with T. evansi. Twenty four animals were divided in two groups with 12 animals each. Group A was formed by healthy Wistar rats (uninfected) and group B composed by animals infected with T. evansi. Both groups were divided into two subgroups (n=6) from which were collected serum and testicular fragments on day five and 15 post-infection. A significant reduction (P<0.01) in the levels of LH, FSH, testosterone and estradiol associated to the increase in cortisol levels was observed in serum of infected animals when compared to negative control. Also an increase in the concentrations of nitrite/nitrate (NOx), lipid peroxidation and protein oxidation was observed in the testicles. The histopathology showed testicular degeneration in the infected animals. Based on these results, we can conclude that infection with T. evansi may reduce the reproductive capacity of male and/or inducing infertility in rats, either directly or indirectly. / A infecção por Trypanosoma evansi causa diversas patologias em animais, assim como problemas reprodutivos cuja patogenia não está totalmente elucidada. Em virtude disso, o objetivo deste estudo foi avaliar a concentração sérica de hormônios reprodutivos, marcadores de estresse oxidativo e histopatologia de testículos de ratos infectados experimentalmente por T. evansi. Foram usados 24 ratos Wistar, divididos em dois grupos com 12 animais cada. O grupo A foi formado por roedores sadios e o grupo B por animais infectados com T. evansi. Estes grupos foram divididos em subgrupos (n=6) para coleta de amostras nos dias 5 (A1 e B1) e 15 pós-infecção. No soro, foi observado uma redução significativa (P<0.01) nos níveis de LH, FSH, testosterona e estradiol associado ao aumento nos níveis de cortisol nos animais infectados quando comparado ao controle negativo. Também foi verificado um aumento nas concentrações de nitrito/nitrato, peroxidação lipídica e oxidação proteica nos testículos, sugestivo de lesão celular, e que foi confirmada na histopatologia com observação de degeneração testicular nos roedores infectados. Com base nestes resultados, podemos concluir que a infecção por T. evansi pode reduzir a capacidade reprodutiva do macho e/ou causar infertilidade em ratos, de forma direta ou indireta.
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Giardia duodenalis – deciphering barrier break down in human, organoid-derived duodenal monolayersHolthaus, David 20 March 2023 (has links)
Das Protozoon Giardia duodenalis ist eine der Hauptursachen für infektiöse Magen-Darm-Erkrankungen. Die zugrundeliegenden Pathomechanismen sind jedoch nach wie vor unklar. Um die Pathogenität G. duodenalis‘ untersuchen zu können, wird ein Modellsystem benötigt, dass die Komplexität des Darmepithels widerspiegelt.
Diese Arbeit zeigt die Etablierung eines Zellkultursystems auf der Basis von organoid-abgeleiteten Epithelien unter Verwendung von filter-basierten Zellkultureinsätzen. Wir haben Protokolle für die Etablierung von organoid-basierten Zellkulturen (ODMs) vier verschiedener Wirte zoonotischer Protozoen unter Verwendung eines einzigen Protokolls erstellt. Die Charakterisierung zeigte, dass das Modellsystem erfolgreich die Polarisierung des Darmepithels nachahmt, aus mehreren Zelltypen besteht und eine Infektion ermöglicht.
Der Schwerpunkt der Arbeit lag auf der Analyse der durch G. duodenalis induzierten Barrierestörung in ODMs auf Transkriptions-, Protein- und Funktionsebene. Die Infektion von humanen duodenalen Zellen führte zu einem Verlust der epithelialen Barrierefunktion. Mit Hilfe des transepithelialen elektrischen Widerstandes und Dextran Flux wurde eine Erhöhung der Barrieredurchlässigkeit beobachtet. Die Hemmung von zuvor in immortalisierten Zellmodellen beschriebenen Reaktionswegen konnte die Barrierefunktion nicht wiederherstellen. Stattdessen konnten Veränderungen der Ionenhomöostase sowie den Zusammenbruch der zonula occludens nachgewiesen werden. Der beobachtete Phänotyp konnte auf die Aktivierung des cAMP/PKA/CREB-Signalwegs, als einen von mehreren kausalen Faktoren, zurückgeführt werden.
Hier zeigen wir die Etablierung eines aus Organoiden abgeleiteten Modells, das die Untersuchung von G. duodenalis Infektionen in vitro ermöglicht. Mit unserem Modell konnten wir eine neue Reihenfolge von Ereignissen entschlüsseln, die einen der Faktoren während symptomatischer Giardiasis darstellt. / The protozoan Giardia duodenalis is a one of the major causes of gastrointestinal illness. Underlying pathomechanisms remain unclear. An in vitro model system that also mimics the complexity of intestinal epithelium is needed to allow pathogenicity studies.
This thesis shows the establishment of a cell culture system based on organoid-derived epithelia using permeable cell culture inserts. We have provided guidelines on the establishment of organoid-derived monolayers (ODMs) of four different hosts of zoonotic protozoa using a single protocol. Characterization showed that the model system successfully mimics intestinal polarization, is composed of multiple cell types and allows for infection with multiple protozoan parasites.
As the main focus of the thesis, analysis of G. duodenalis-induced barrier breakdown in ODMs was performed on transcriptional, protein and functional level. Infection of human duodenal, organoid-derived monolayers resulted in a time- and dose-dependent breakdown of epithelial barrier function. Barrier permeability increases were observed ranging from ions to macromolecules as measured by transepithelial electrical resistance and Dextran flux. Inhibition of previously proposed key pathogen-induced pathways observed in immortalized cell models did not rescue barrier dysfunction. We could instead show changes in ion homeostasis, and tight junctional breakdown. While none of the previously proposed effector pathways appeared to be responsible, we could pin-point the observed phenotype to activation of the cAMP/PKA/CREB signaling pathway, as one of the factors of the multifactorial barrier breakdown.
The establishment of an organoid-derived infection model is shown, allowing the study of in vitro Giardia duodenalis infections. Using this model, we could decipher a new series of events that may be one of the factors causing the intestinal barrier breakdown observed in symptomatic Giardiasis.
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Improved diagnosis of trypanosome infections and drug resistant T.congolense in livestockDelespaux, Vincent F.P. 26 January 2005 (has links)
The aim of this thesis was to provide a picture of the trypanosomosis and drug resistance prevalence in Eastern Province of Zambia, to understand the underlying factors of drug resistance (drug use habits), to improve the diagnosis of trypanosomosis in livestock and finally, to improve the diagnosis of isometamidium resistance in T.congolense. After an introductory part where available trypanosomosis and trypanocide resistance diagnostic methods are described and discussed, the body of the thesis is divided in two main sections. In the first section are presented the results of a cross-sectional and a longitudinal epidemiological survey describing the geographical distribution of trypanosomosis cases, of resistant isolates and of cattle treated with isometamidium chloride. The results of the monitoring of unsupervised treatments of cattle with isometamidium by farmers and veterinary assistants with the Isometamidium-ELISA technique are also presented. The second section describes the development of two new diagnostic methods, the first one allowing the diagnosis of trypanosome infections with high sensitivity and specificity through semi-nested polymerase chain reaction and restriction fragment length polymorphism. This is the first report of a pan-trypanosome PCR test (a single PCR test for the diagnosis of all important pathogenic trypanosomes of cattle). The second new method that was developed allows the diagnosis of isometamidium resistant T.congolense strains by PCR-RFLP. This is the first report of a PCR based diagnostic test of trypanocide resistance in T. congolense.<p> / Doctorat en sciences, Spécialisation biologie moléculaire / info:eu-repo/semantics/nonPublished
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Models for adaptive feeding and population dynamics in planktonPiltz, Sofia Helena January 2014 (has links)
Traditionally, differential-equation models for population dynamics have considered organisms as "fixed" entities in terms of their behaviour and characteristics. However, there have been many observations of adaptivity in organisms, both at the level of behaviour and as an evolutionary change of traits, in response to the environmental conditions. Taking such adaptiveness into account alters the qualitative dynamics of traditional models and is an important factor to be included, for example, when developing reliable model predictions under changing environmental conditions. In this thesis, we consider piecewise-smooth and smooth dynamical systems to represent adaptive change in a 1 predator-2 prey system. First, we derive a novel piecewise-smooth dynamical system for a predator switching between its preferred and alternative prey type in response to prey abundance. We consider a linear ecological trade-off and discover a novel bifurcation as we change the slope of the trade-off. Second, we reformulate the piecewise-smooth system as two novel 1 predator-2 prey smooth dynamical systems. As opposed to the piecewise-smooth system that includes a discontinuity in the vector fields and assumes that a predator switches its feeding strategy instantaneously, we relax this assumption in these systems and consider continuous change in a predator trait. We use plankton as our reference organism because they serve as an important model system. We compare the model simulations with data from Lake Constance on the German-Swiss-Austrian border and suggest possible mechanistic explanations for cycles in plankton concentrations in spring.
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Optimization and verification of changes made to US-EPA 1623 Method to analyse for the presence of Cryptosporidium and Giardia in waterKhoza, M. N. L. (Mtetwa) 03 1900 (has links)
Thesis. (M. Tech. (Dept. of Biosciences, Faculty of Applied and Computer Sciences))--Vaal University of Technology, 2010 / Methods for detecting the presence of Cryptosporidium oocysts and Giardia cysts have been developed and continuous improvement is being done to improve the recovery rate of the target protozoa. Rand Water has adopted their method for isolation and detection of Cryptosporidium oocysts and Giardia cysts in water from United State Environmental Protection Agency (US-EPA) Method 1623, 1999. In 2005 changes were made by US-EPA to the Method 1623.
A study was done to improve the performance of the Rand Water Method 06 (2007) used for isolation and detection of Cryptosporidium oocysts and Giardia cysts. Three methods namely: Rand Water Method 06 (2007), US-EPA Method 1623 (2005) and Drinking Water Inspectorate standard operating procedures (2003) were compared and key different steps in the methods were identified (wrist action speed, centrifuge speed, immunomagnetic separation procedures and addition of pre-treatment steps). Different experiments were conducted to verify and evaluate the difference between two wrist action shaker speeds, three different centrifuge speeds, two slightly different immunomagnetic separation procedures and when a pre-treatment step was included in the method.
Three different types of water matrices (reagent grade water, drinking water and raw water) were used for the experiments and secondary validation. Data obtained from the experiments and secondary validation was statistically analyzed to determine whether there was a significant difference in the recovery of Cryptosporidium oocysts and Giardia cysts. Secondary validation of the Rand Water Method 06 (2007) was performed by implementing the study experiments‟ findings into the method.
The results indicated an increase in the recovery rate of Cryptosporidium oocysts and Giardia cysts when data was compared with the previous secondary validation report. The mean recovery of Cryptosporidium oocysts in reagent grade water samples increased from 31% to 55%, drinking water samples increased from 28% to 44% and raw water decreased from 42% to 29%. The mean recovery of Giardia cysts in reagent grade water samples increased from 31% to 41%, drinking water samples increased from 28% to 46% and raw water decreased from 42% to 32%.
Furthermore, even though the recovery rate of raw water decreased the use of pre-treatment buffer reduced the number of IMS performed per sample by reducing the pellet size. Enumeration of microscope slides was also easier as there was less background interference. The optimization of the Rand Water Method 06 (2007) was successful as the recovery rate of Cryptosporidium oocysts and Giardia cysts from water increased. All the changes that were verified and that increased the recovery rate were incorporated into the improved Rand Water Method 06.
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Avaliação de diversos métodos de detecção de cistos de Giardia spp. e Oocistos de Cryptosporidium parvum presentes no resíduo gerado após o tratamento de água de abastecimento com turbidez elevada / Evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum Oocysts in wastes produced after high- turbidity water treatmentGiglio, Guilherme Lelis 24 August 2015 (has links)
Este trabalho teve como objetivo avaliar diversos métodos de detecção e recuperação de cistos de Giardia spp. e de oocistos de Cryptosporidium parvum em resíduos gerados no tratamento de águas de abastecimento com turbidez elevada tendo como padrão o Método 1623.1 da USEPA (2012 ). Para tanto, ensaios utilizando aparelho Jarteste (coagulação, floculação, decantação e filtração ) foram realizados utilizando o coagulante cloreto de polialumínio - PAC. Em todos os métodos avaliados foi utilizada a técnica de purificação por separação imunomagnética - IMS. A adaptação do método floculação em carbonato de cálcio FCCa elaborado por Vesey et al. (1993) e adaptado por Feng et al. (2011), repercutiu nos melhores resultados para a amostra de resíduo sedimentado, com recuperações de 68 ± 17 % para oocisto de C. parvum e de 42 ± 7 % para cisto de Giardia spp. Entretanto, as recuperações para a amostra de água de lavagem dos filtros - ALF foram inferiores à 1 %, não sendo possível determinar um método adequado. A presença dos patógenos indica que o reuso da ALF em ETA convencionais ou o descarte em mananciais sem um tratamento prévio, pode representar problemas de contaminação. A adaptação dos métodos de Boni de Oliveira (2012) e Keegan et al. (2008), também repercutiram em porcentagens de recuperação expressivas para a amostra de resíduo sedimentado, sendo de: 41 ± 35 % para oocisto de C. parvum e 11 ± 70 % para cisto de Giardia spp., e 38 ± 26 % para oocisto de C. parvum e 26 ± 13 % para cisto de Giardia spp., respectivamente. A análise estatística não resultou em diferença significativa entre estes dois métodos, entretanto, as elevadas recuperações indicam que estes métodos podem ser melhor avaliados em pesquisas futuras. / This dissertation addresses the evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum oocysts in wastes produced after a high-turbidity water treatment, according to Method 1623.1 from USEPA (2012). Coagulant polyaluminium chloride - PACl was used in jar test experiments (coagulation/flocculation, sedimentation and filtration ). The Immunomagnetic Separation - IMS technique was applied to all methods. The calcium carbonate flocculation (CCF) method, developed by Vesey et al. (1993) and adapted by Feng et al. (2011 ), was applied to sludge samples in this research and was the best method tested, with 68% ± 17 % and 42 % ± 7,00 % recoveries for C. parvum oocysts and Giardia spp. cysts, respectively. On the other hand, the percentage recovery of (oo)cysts for filter backwash water samples was lower than 1 % and no suitable method could be detected. The presence of pathogens represents contamination risks for water sources and the reuse of filter backwash water may be a problem to conventional water treatment plants. The application of Boni de Oliveira (2012) and Keegan et al. (2008) methods, adjusted to this study, also resulted in significant percentage recoveries for the sludge samples, with 41 ± 35 % for C. parvum oocyst and 11 ± 70% for cyst Giardia spp., and 38 ± 26% for oocyst C. parvum and 26 ± 13% for cyst Giardia spp., respectively. The statistical analysis showed no significant differences between the two methods, however, such high recoveries indicate they should be better evaluated in future research.
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Le Cénomanien de Tunisie centrale : étude paléoecologique, stratigraphique, micropaléontologique et paléogeographiqueGargouri Razgallah, Saloua 22 December 1983 (has links) (PDF)
L'objectif de cet ouvrage est d'établir un schéma d'évolution paléogéographique de la plate-forme cénomanienne permettant de replacer géographiquement les différents domaines sédimentologiques. Tracer le paysage de Tunisie centrale au cours du Cénomanien, n'est autre qu'une analyse et une compréhension des faciès et de l'environnement. Il a fallu d'abord tenter, dans la mesure du possible, d'esquisser une biozonation basée non seulement sur les foraminifères benthiques et planctoniques, mais aussi les ammonites et les ostracodes. Cette biozonation appelait à son tour une étude systématique. C'est dans cette direction que s'est engagée la présente recherche
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Protozo?rios de vida livre em ambientes aqu?ticos do RN: ocorr?ncia, caracteriza??o e import?ncia para a educa??o b?sica / Free-living protozoa in aquatic environments of the RN: occurrence, characterization and importance to basic educationMedeiros, Maria Luisa Quinino de 07 February 2012 (has links)
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Previous issue date: 2012-02-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Water is considered an essential right to life, besides being a determinant of economic development and social
welfare, represented by both the quantity available, and the quality. In semi-arid Northeast, droughts occurring
on a regular basis combined with human activities, aggravate the situation regarding the conservation of water
resources in this area. To alleviate this condition is common to construction of artificial reservoirs, such as
reservoirs and dams. As in natural aquatic environments, these reservoirs are potential sites for the proliferation,
growth and development of diverse biological communities, whether of animals, plants and microorganisms.
Research on the composition and ecology of these communities, especially microbial, are still restricted. One of
the least studied groups in these environments are free-living protozoa, which over time have been neglected and
after discoveries about its various functions in the aquatic ecosystem are beginning to receive more attention
from scholars. They are, in quantitative terms, the most important consumers of microorganisms (mainly bacteria
and algae) in aquatic environments, and therefore control the abundance of these. They may therefore influence
the structure of the aquatic food chain in terms of species composition, abundance, biomass and biodiversity.
Despite the recognition of the importance of protozoa in the final of the trophic transfer in aquatic environments,
there are few data and, in general, are still precarious knowledge of them. Given the importance of protozoa in
aquatic environments and the paucity of research on this group, especially in the state of Rio Grande do Norte,
the present study aimed at identifying the genus and species of free-living protozoa that are present in the
Armando Ribeiro Gon?alves Dam as well as to relate the occurrence and dynamics of the trophic conditions in
the environment in which they are inserted, in order to support the hypothesis that species that are in these
environments can serve to indicate the water quality. We observed the presence of 65 taxa of free-living
protozoa, of which 29 were identified at the species level. There was a similarity space in taxonomic
composition of protozoa, suggesting a possible regulation of this type of community for limnological variables
other than those studied in this work (chlorophyll a, pH, temperature). Although it was aimed to analyze the
conceptions of teachers and students from nearby towns Dam Armando Ribeiro Gon?alves, on issues relating to
water quality and the role of protozoa. For this, we applied questionnaires with teachers and pupils of public
schools of San Rafael and Itaj?. It was concluded that teachers and students recognize the multi-dam Armando
Ribeiro Gon?alves, although unaware of important aspects of the dynamics and ecology of this environment.
Conceptions of teachers and students are matched at various times, especially with regard to waterborne
diseases. In an attempt to identify possible misconceptions about the knowledge of the protozoa, assuming that
these organisms have neglected their ecological role, and are seen as only, disease, a study was done with
teachers and students, following a particular methodology that allowed look so clear and precise results. It was
clear that knowledge about the free-living protozoa is still quite limited. The alternative conceptions that were
found show a direct relation of protozoans and diseases. From the data obtained by these studies, we planned a
series of science communication activities, environmental education and health education in schools close to
study environments in order to promote a didactic transposition of accumulated knowledge about these
organisms, favoring continuing education of teachers and the increase of information to the local community
through the knowledge of biodiversity and ecology of these organisms. Moreover, the results found in this study
and reflections on it that led to propose the elaboration of a book Readers with an emphasis on the group of freeliving
protozoa in the populations for use in public schools in the region where it was developed the semiarid
work / A ?gua ? considerada um bem imprescind?vel ? vida, al?m de ser um fator condicionante do desenvolvimento
econ?mico e do bem-estar social, representado tanto pela quantidade dispon?vel, como pela qualidade. No
semi?rido nordestino, as secas que ocorrem de forma peri?dica aliada a atividades antr?picas, agravam a situa??o
da conserva??o dos recursos h?dricos nessa localidade. Para amenizar essa condi??o ? comum a constru??o de
reservat?rios artificiais, como a?udes e barragens. Assim como nos ambientes aqu?ticos naturais, estes
reservat?rios s?o locais prop?cios para a prolifera??o, crescimento e desenvolvimento de diversas comunidades
biol?gicas, seja de animais, vegetais e de microrganismos. As pesquisas sobre a composi??o e ecologia dessas
comunidades, sobretudo as microbianas, ainda s?o restritas. Um dos grupos menos estudados nesses ambientes
s?o os protozo?rios de vida livre, que ao longo do tempo foram negligenciados e depois de descobertas sobre
suas variadas fun??es no ecossistema aqu?tico come?am a receber mais aten??o por parte dos estudiosos. Eles
s?o, em termos quantitativos, os mais importantes consumidores de microrganismos (principalmente algas e
bact?rias) nos ambientes aqu?ticos, e, por isso controlam a abund?ncia destes. Eles influenciam, portanto, a
estrutura da cadeia alimentar aqu?tica em termos de composi??o de esp?cies, abund?ncia, biomassa e
biodiversidade. Apesar do reconhecimento da import?ncia dos protozo?rios no balan?o final das transfer?ncias
tr?ficas em ambientes aqu?ticos, existem poucos dados e, de um modo geral, s?o, ainda, prec?rios os
conhecimentos sobre eles. Tendo em vista a import?ncia dos protozo?rios em ambientes aqu?ticos e a escassez
de pesquisas relacionadas a este grupo, sobretudo no Estado do Rio Grande do Norte, o presente estudo teve -
como objetivo identificar os g?neros e esp?cies de protozo?rios de vida livre que est?o presentes na Barragem
Armando Ribeiro Gon?alves, bem como relacionar a ocorr?ncia e a din?mica destes com as condi??es tr?ficas
do ambiente no qual est?o inseridos, com o intuito de corroborar a hip?tese de que as esp?cies que est?o nesses
ambientes podem servir para indicar a qualidade da ?gua. Registrou-se a presen?a de 65 t?xons de protozo?rios
de vida livre, dos quais 29 foram identificados em n?vel de esp?cie. Observou-se uma similaridade espacial na
composi??o taxon?mica dos protozo?rios, sugerindo-se uma poss?vel regula??o desse tipo de comunidade por
outras vari?veis limnol?gicas diferentes daquelas estudadas nesse trabalho (clorofila-a, pH, temperatura). Ainda
objetivou-se analisar as concep??es de professores e alunos, das cidades pr?ximas da Barragem Armando
Ribeiro Gon?alves, sobre as tem?ticas relativas ? qualidade de ?gua e do papel dos protozo?rios. Para isso, foi
aplicado question?rios com professores e alunos de escolas estaduais de S?o Rafael e Itaj?. Concluiu-se que os
professores e alunos reconhecem as m?ltiplas funcionalidades da Barragem Armando Ribeiro Gon?alves, apesar
de desconhecerem aspectos importantes da din?mica e ecologia desse ambiente. As concep??es de professores e
alunos se igualaram em v?rios momentos, principalmente no tocante ?s doen?as de veicula??o h?drica. Na
tentativa de identificar poss?veis concep??es alternativas sobre o conhecimento dos protozo?rios, partindo da
hip?tese que esses organismos t?m seu papel ecol?gico negligenciado, e s?o vistos como, somente, transmissores
de doen?as, foi feito um estudo com professores e alunos, seguindo determinada metodologia que permitiu
analisar de forma clara e precisa os resultados. Ficou claro que o conhecimento sobre os protozo?rios de vida
livre ?, ainda, bastante limitado. As concep??es alternativas que foram evidenciadas mostram uma rela??o direta
de protozo?rios e doen?as. A partir dos dados obtidos por todos esses estudos, planejou-se uma s?rie de
atividades de divulga??o cient?fica, educa??o ambiental e educa??o em sa?de nas escolas pr?ximas aos
ambientes de estudo com o intuito de promover uma transposi??o did?tica do conhecimento acumulado sobre
esses organismos, favorecendo a forma??o continuada de professores e o incremento de informa??es ?
comunidade local por meio do conhecimento da biodiversidade e ecologia desses organismos. Al?m disso, os
resultados encontrados neste estudo e as reflex?es feitas sobre ele levaram a que se propusesse a elabora??o de
um livro paradid?tico com ?nfase sobre o grupo dos protozo?rios de vida livre para uso junto ?s popula??es de
escolas p?blicas da regi?o semi?rida onde foi desenvolvido o trabalho
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Protozo?rios de vida livre em dois trechos da bacia hidrogr?fica do Rio Pirangi (RN): rela??es com a educa??o em ci?ncias e preserva??o / Free-living protozoa in thwo section of the Pirangi River watershed (RN): relations to the science education and preservationLobato J?nior, Wellington Sena 07 March 2013 (has links)
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Previous issue date: 2013-03-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The vast hidric wealth of Brazil gets its watersheds more susceptible to impacts that
compromise the water quality, affecting the ecosystem stability of aquatic environments. The
decrease in the quality of water resources also results in a decrease of its multiple uses,
especially in tourist areas of the coast, where the continuous flow of people to these sites
increases even further the probability of inappropriate behavior of both tourists and local
residents. Studies regarding the microbiological communities are still scarce, especially on the
free-living protozoa that play unique roles in the food chain of aquatic ecosystems. Due to the
large role played by this group of microorganisms in aquatic environments, the present study
aimed at identifying the genus and species of free-living protozoa present in two sections of
the Pium River, east coast of Rio Grande do Norte, making an association between the its
occurrence and trophic conditions of the environment in which they are, also checking the
bioindicator capacity of these organisms in water quality. It also aimed to conduct a survey
with students to identify the main difficulties regarding the knowledge of free-living protozoa
and hydric transmission diseases in two public schools near the river studied in the Pium
district, county of Parnamirim. The survey was analyzed by means of questionnaires at both
schools. Students identified several activities developed Pium river, highlighting its
multifunctionality and importance to the region. A total of 76 taxa of free-living protozoa was
recorded, of these, 33 were ciliates, 19 flagellates and 24 sarcodia. The spatial and temporal
patterns of these organisms to both points studied revealed the bioindicator potentiality of
some effective species identified. However, knowledge about the free-living protozoa proved
quite lagged, presenting misconceptions that show them as pathogenic organisms exclusively,
totally disregarding their ecological role. In order to remedy the flaws existing in students in
relation to the functional role of protozoa, workshops were planned on these microorganisms
while also addressing issues related to hydric transmission diseases through lectures,
recreational activities and interactive presentations. These practical activities of Science
Education had the goal of bringing students the context of local water resources, aiming to
promote a greater clarification regarding of the functional role of free-living protozoa in
aquatic environments / A vasta riqueza h?drica do Brasil deixa suas bacias hidrogr?ficas mais suscet?veis a impactos
que comprometam a qualidade da ?gua, afetando a estabilidade ecossist?mica dos ambientes
aqu?ticos. A diminui??o da qualidade dos recursos h?dricos resulta tamb?m na diminui??o dos
seus usos m?ltiplos, principalmente em regi?es tur?sticas do litoral, onde o fluxo cont?nuo de
pessoas a esses locais aumenta ainda mais a probabilidade de comportamentos inadequados
tanto dos turistas quanto dos residentes locais. Os estudos a respeito das comunidades
microbiol?gicas ainda s?o escassos, principalmente as de protozo?rios de vida livre, que
desempenham fun??es singulares dentro da cadeia alimentar dos ecossistemas aqu?ticos.
Devido ao grande papel desempenhado por este grupo de microrganismos nos ambientes
aqu?ticos, o presente estudo teve por objetivo identificar os protozo?rios de vida livre, em
g?nero e esp?cie, presentes em dois trechos do Rio Pium, litoral leste do Rio Grande do
Norte, fazendo uma rela??o entre a ocorr?ncia e as condi??es tr?ficas do ambiente em que se
encontram. Tamb?m se objetivou realizar uma sondagem junto aos alunos para identificar as
principais dificuldades quanto ao conhecimento dos protozo?rios de vida livre e doen?as de
veicula??o h?drica em duas escolas p?blicas pr?ximas ao rio estudado, no distrito de Pium,
munic?pio de Parnamirim. A sondagem foi analisada por meio de question?rios aplicados em
ambas as escolas. Foi registrado um total de 76 t?xons de protozo?rios de vida livre, destes,
sendo 33 ciliados, 19 flagelados e 24 sarcod?neos. Os padr?es espaciais e temporais desses
organismos nos dois pontos estudados revelaram a potencialidade bioindicadora eficaz de
algumas esp?cies identificadas. Os alunos identificaram diversas atividades desenvolvidas no
Rio Pium, destacando sua multifuncionalidade e import?ncia para a regi?o. Por?m, o
conhecimento sobre os protozo?rios de vida livre mostrou-se bastante defasado, apresentando
concep??es alternativas que os evidenciam como organismos exclusivamente patog?nicos,
desconsiderando totalmente seu papel ecol?gico primordial. Com o prop?sito de minimizar os
poss?veis equ?vocos existentes nos alunos em rela??o ao papel funcional dos protozo?rios,
foram planejadas oficinas did?ticas sobre estes microrganismos, abordando tamb?m temas
relacionados a doen?as de veicula??o h?drica por meio de palestras, atividades l?dicas e
apresenta??es interativas. Estas atividades pr?ticas de Educa??o em Ci?ncias tiveram o intuito
de aproximar os alunos do contexto dos recursos h?dricos locais, almejando-se promover um
maior esclarecimento sobre o papel funcional dos protozo?rios de vida livre nos ambientes
aqu?ticos
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