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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.
41

Vliv aktivity vody na obsah mikroorganizmů ve vybraných masných výrobcích / The influence of water activity on the microbiological content in meat products

BURIANOVÁ, Michaela January 2019 (has links)
The aim of this thesis is to monitor how the amount of water (water activity) affects the amount of microorganisms is selected packaged meat products from the point of view standards, which specify their specific requirements for the health safety of these products. The first part of this work describes various types of packaging materials of meat products, the microorganisms that occur in them and the definition of water activity. The second part describes the actual measurement of water activity and the measurement of the occurrence of microorganisms and coliforms, from selection of suitable meat products, their types of packaging, sample preparation and evaluation of measured methods. The results showed, that the activity of water affects the occurrence of microorganisms and coliforms, in that the higher the activity of water, the higher microorganisms presence.
42

Caracterização físico-química e qualidade microbiológica de amostras de mel de abelhas sem ferrão (Apidae, Meliponinae) do Estado da Bahia, com ênfase em Melipona Illiger, 1806 / Physico-chemical characterization and microbiological quality of stingless bees (Apidae, Meliponinae) honey samples from the State of Bahia, Brazil, with emphasis on Melipona Illiger, 1806

Souza, Bruno de Almeida 18 February 2008 (has links)
Aproveito este espaço para contar um pouco da minha trajetória com as abelhas, mas também para falar sobre as atividades desenvolvidas e possibilidades surgidas no decorrer do curso de Doutorado, informações estas que normalmente passam despercebidas. Nascido em Salvador, tive meu primeiro contato com as abelhas com pouco mais de 12 anos por iniciativa de meu pai, que nesta época já era um entusiasta pela atividade e possuía conhecimentos práticos. Alguns anos após, fizemos nosso primeiro curso de iniciação em apicultura para consolidar as nossas experiências práticas e as informações obtidas em literatura. Terminei por cursar a graduação em Engenharia Agronômica na Escola de Agronomia da UFBA, atualmente Centro de Ciências Agrárias, Ambientais e Biológicas da Universidade Federal do Recôncavo da Bahia. Foi um período de crescimento em que me envolvi com atividades de iniciação científica, em outras áreas que não apicultura. Já no mestrado, me foi dada a oportunidade de trabalhar com um grupo de abelhas até então novo para mim, os meliponíneos, e de ter como orientador o Prof. Dr. Carlos Alfredo Carvalho, pessoa que me direcionou para o futuro curso de doutorado na USP, dando continuidade à linha de pesquisa iniciada no mestrado. Em 2004 iniciei o meu doutoramento na ESALQ/USP sob orientação do Prof. Dr. Luis Carlos Marchini. Fazendo um balanço desta última etapa, além do desenvolvimento das atividades regulares do programa tive a oportunidade de me envolver com a formulação de projetos de pesquisa para agências de fomento, de participar de eventos nacionais e internacionais, de publicar artigos científicos e de consolidar parcerias de trabalho no Brasil e no exterior. Em síntese, este período de doutorado que se encerra (2004 - 2008) pode ser representado em números por: quatro cursos realizados como formação complementar, quatro premiações em eventos científicos, nove trabalhos publicados em periódicos (alguns submetidos antes de ingressar no doutorado), quatro livros, três capítulos de livros, três cartilhas, dois textos em revista de divulgação, quatro trabalhos completos publicados em anais de congressos, 40 resumos, 17 trabalhos apresentados e participação em 12 eventos técnico-científicos; além do envolvimento em atividades de monitoria junto a disciplinas de graduação, treinamento este fundamental para uma futura atividade de docência. Acredito que todas estas amizades feitas, parcerias consolidadas, atividades desenvolvidas e produções decorrentes do doutorado contribuirão de forma substancial e decisiva para esta nova etapa que se inicia em minha vida. / The stingless bees honey is a product presenting a growing market demand but, in spite of its consumption as food and even medicinal use, there are few studies to define quality standards for its commercialization. This work was carried out to determine the physico-chemical characteristics and microbiological quality of honey samples produced by meliponid species from Bahia State, Brazil, contributing to the establishment of quality control standards of this product. Forty-seven samples collected from December 2004 to May 2006 were analyzed, being determined their physico-chemical characteristics and microbiological quality, regarding to the standard counting of moulds and yeasts, and presence of microorganisms of the coliform group. Concerning the physico-chemical characteristics, the obtained medium values, excepting moisture content, fulfill the quality criteria established by the current Brazilian Legislation. Considering the number of samples individually disqualified, adjustments in reducing sugars limits should be made for best attend to the requirements of meliponid honey, as well as the use of the diastasic activity in the Melipona honeys as quality criterion. In the microbiologic analyses, 53.2% of the honey samples presented standard counting for moulds and yeasts above the maximum value allowed by the Brazilian Legislation. For microorganisms of the coliform group only one sample was positive for coliform at 35ºC. The presence of these microorganisms, mainly moulds and yeasts, even in samples aseptically harvested indicates the need of identification of this microbiota and its possible natural occurrence in the honey produced by this group of bees.
43

Avaliação dos controles microbiológicos e do programa de redução de patógenos no abate de bovinos /

Caselani, Kelly. January 2010 (has links)
Orientador: Luiz Francisco Prata / Banca: Gener Tadeu Pereira / Banca: Anna Monteiro Correia Lima Ribeiro / Resumo: Este trabalho teve por finalidade avaliar o resultado dos controles ambientais e operacionais, rotineiros e derivados do plano APPCC - Análise de Perigos e Pontos Críticos de Controle, aplicados ao abate de bovinos, e da pesquisa de microrganismos potencialmente patogênicos (Escherichia coli O157:H7, Salmonella enterica e Listeria monocytogenes). Com duração de um ano, a pesquisa foi desenvolvida em abatedouro-frigorífico habilitado à exportação localizado no Estado de São Paulo, Brasil. Foram analisadas 411 amostras ambientais para pesquisa de Listeria spp., 1.192 amostras de superfície de contato para a Contagem Bacteriana Total (CBT), 200, 100, 775, 264 e 100 amostras de superfície de carcaça para CBT, Coliformes totais, E. coli, Salmonella spp. e E. coli O157:H7, respectivamente, além de 256 amostras de recortes cárneos para a pesquisa de E. coli O157:H7. Os resultados evidenciaram condição higiênica aceitável para 51,1% das amostras ambientais de CBT, com 62,9% de amostras não aceitáveis no setor de abate. Um valor elevado de amostras (15,1%) foi positivo para Listeria spp. e para Listeria monocytogenes (4,6%). Observou-se que 89,6%, 2,8% e 7,6% das amostras de carcaça foram satisfatórias, aceitáveis e insatisfatórias para E. coli, respectivamente. Para a amostragem comparativa, 88,5% das amostras apresentaram-se satisfatórias para CBT, 84% para Coliformes Totais e 83,6% para E. coli. Nenhuma das amostras de carcaça analisadas foi positiva para Salmonella spp. ou para E. coli O157:H7. A frequência da ocorrência de E. coli O157:H7 em amostras de recortes cárneos (carne industrial) foi de 0,31%, com apenas uma amostra positiva / Abstract: This study aimed to evaluate the result of the environmental and operational controls which are routine or derived from HACCP Plan - Hazard Analysis and Critical Control Points, applied to slaughter cattle, and potentially pathogenic microorganisms research (Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes). During one year, the research was developed in a slaughterhouse, enabled to export, located in the state of São Paulo, Brazil. We analyzed 411 environmental samples for Listeria spp. research, 1.192 samples of surface contact for Total Bacterial Count (TBC), 200, 100, 775, 264 and 100 samples of carcass surface for TBC, Total Coliform, E. coli, Salmonella spp. and E. coli O157:H7, respectively, besides 256 samples of meat cuts for E. coli O157:H7 research. The results showed that 51,1% of the environmental samples of TBC were in acceptable hygienic condition and 62,9% of samples were not acceptable in the slaughter industry. A high value of samples (15,1%) was positive for Listeria spp. and Listeria monocytogenes (4,6%). It was observed that 89,6%, 2,8% and 7,6% of the samples of carcass were satisfactory, acceptable and unsatisfactory for E. coli, respectively. For comparative sampling, 88,5% of the samples were satisfactory for TBC, 84% for Total Coliform and 83, 6% for E. coli. None of the samples of carcass tested was positive for Salmonella spp. or E. coli O157:H7. The frequency of the occurrence of E. coli O157:H7 in samples of meat cuts (meat industry) was 0,31%, with only one positive sample / Mestre
44

Estudo comparativo entre oito sistemas de lagoas de estabilização da região noroeste do Estado de São Paulo / Comparative study of eight systems of stabilization ponds in the northwestern region of São Paulo

Gomes, João Luiz Cais da Silva 10 April 2002 (has links)
Este trabalho comparou oito lagoas de estabilização da região Noroeste do Estado de São Paulo, que tratam esgotos predominantemente sanitários de Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Irapuã e Adolfo, cidades pequenas, com no máximo 5500 habitantes (1700 ligações), onde os quatro primeiros sistemas são compostos apenas por lagoas facultativas primárias e os quatro últimos por lagoas anaeróbias e lagoas facultativas secundárias. Vinte e cinco variáveis físicas, químicas e biológicas foram analisadas em amostras compostas coletadas entre 24/05/2000 e 03/10/2000. A análise da batimetria efetuada fornece indicações de prazos para a remoção do lodo do fundo das lagoas. As taxas de acúmulo de lodo médias obtidas para as lagoas anaeróbias e facultativas primárias foram de 0,07 e 0,14 m3/hab.ano, respectivamente. O pH do efluente das lagoas anaeróbias e das facultativas foi em média 6,6 e 7,4. Nas lagoas anaeróbias observou-se alta remoção de sólidos suspensos e de Demanda Bioquímica de Oxigênio (DBO) com eficiência geral média de 64% e 61% respectivamente. Os sistemas não atenderam plenamente à legislação no tocante a eficiência de remoção de DBO de 80%, porém o valor médio encontrado para os oito sistemas foi de 78%, bastante próximo do exigido. Sugere-se para a região, para eficiência de remoção de DBO de 80%, lagoas anaeróbias com tempo de detenção de 5 dias e para as lagoas facultativas primárias e secundárias tempos de detenção de 25 e 15 dias respectivamente, e taxas de aplicação superficial de 140 e 130 kg DBO/ha.dia, respectivamente. Não foi atingido o limite máximo de 1000 coliformes fecais por 100 ml, obtendo-se média geral de remoção de 97,40% inferindo-se que há necessidade de um processo de tratamento complementar para a remoção de microrganismos. Não observou-se correlação entre eficiência do sistema e relação comprimento/largura das lagoas. Constatou-se maus odores mesmo na ausência de concentrações detectáveis de sulfeto. A remoção média geral de amônio (NH4+), nitrogênio total, fosfato total dissolvido e fósforo total foi de 31%, 12%, 24% e 27% respectivamente nos sistemas estudados. / The present work compared the performance of eight stabilization ponds in the Northwest region of São Paulo state, that treat predominantly the domestic sewage from eight small cities with a maximum of 5000 inhabitants (1700 links): Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Trapuã and Adolfo. The first four systems are made of four primary facultative ponds and the last four by anaerobic ponds and secondary facultative ponds. A total of twenty-five chemical, physical and biological variables were analyzed in integrated samples collected between 24/05/2000 and 03/10/2000. The bathymetric analysis performed has indicated deadlines for sludge removal from the stabilization pond bottom. Mean sludge accumulation rates o btained for anaerobic and primary facultative ponds were 0.07 and 0.14 m3/inhabt.year, respectively. Effluents from anaerobic and facultative ponds had a mean pH of 6.6 and 7.4. In anaerobic ponds a righ rate of suspended solids removal was found and the Biochemical Oxygen Demand (BOD) had an overall general efficiency of 64% and 61%, respectively. The systems did not completely attend the present legislation in respect to a BOD removal of 80%, as required, however the mean value for the eight systems monitored was 78%, very close to the established limit. It is therefore suggested that for this region, in order to attain the removal efficiency of 80% anaerobic ponds should have a residence time of 5 days and the primary and secondary facultative ones should have residence times of 25 and 15 days respectively, coupled to loading rates of 140 and 170 Kg BOD/ha.day respectively. Also, the maximum limit of 1000 fecal coliforms per 100 ml was not reached, and in general there was a mean removal efficiency of 97.40%, indicating that an additional treatment process needs to be implemented for a successful removal of coliforms. No correlation was found between the removal efficiency and morphometry (length/weight) pond characteristics. Bad smell was present even in the absence of detectable amounts of sulfide. The mean efficiency for the removal of ammonium (NH4+), total nitrogen, total dissolved phosphorus and total phosphorus were 31%, 12%, 24%, and 27% respectively, among the systems studied.
45

Estudo comparativo entre oito sistemas de lagoas de estabilização da região noroeste do Estado de São Paulo / Comparative study of eight systems of stabilization ponds in the northwestern region of São Paulo

João Luiz Cais da Silva Gomes 10 April 2002 (has links)
Este trabalho comparou oito lagoas de estabilização da região Noroeste do Estado de São Paulo, que tratam esgotos predominantemente sanitários de Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Irapuã e Adolfo, cidades pequenas, com no máximo 5500 habitantes (1700 ligações), onde os quatro primeiros sistemas são compostos apenas por lagoas facultativas primárias e os quatro últimos por lagoas anaeróbias e lagoas facultativas secundárias. Vinte e cinco variáveis físicas, químicas e biológicas foram analisadas em amostras compostas coletadas entre 24/05/2000 e 03/10/2000. A análise da batimetria efetuada fornece indicações de prazos para a remoção do lodo do fundo das lagoas. As taxas de acúmulo de lodo médias obtidas para as lagoas anaeróbias e facultativas primárias foram de 0,07 e 0,14 m3/hab.ano, respectivamente. O pH do efluente das lagoas anaeróbias e das facultativas foi em média 6,6 e 7,4. Nas lagoas anaeróbias observou-se alta remoção de sólidos suspensos e de Demanda Bioquímica de Oxigênio (DBO) com eficiência geral média de 64% e 61% respectivamente. Os sistemas não atenderam plenamente à legislação no tocante a eficiência de remoção de DBO de 80%, porém o valor médio encontrado para os oito sistemas foi de 78%, bastante próximo do exigido. Sugere-se para a região, para eficiência de remoção de DBO de 80%, lagoas anaeróbias com tempo de detenção de 5 dias e para as lagoas facultativas primárias e secundárias tempos de detenção de 25 e 15 dias respectivamente, e taxas de aplicação superficial de 140 e 130 kg DBO/ha.dia, respectivamente. Não foi atingido o limite máximo de 1000 coliformes fecais por 100 ml, obtendo-se média geral de remoção de 97,40% inferindo-se que há necessidade de um processo de tratamento complementar para a remoção de microrganismos. Não observou-se correlação entre eficiência do sistema e relação comprimento/largura das lagoas. Constatou-se maus odores mesmo na ausência de concentrações detectáveis de sulfeto. A remoção média geral de amônio (NH4+), nitrogênio total, fosfato total dissolvido e fósforo total foi de 31%, 12%, 24% e 27% respectivamente nos sistemas estudados. / The present work compared the performance of eight stabilization ponds in the Northwest region of São Paulo state, that treat predominantly the domestic sewage from eight small cities with a maximum of 5000 inhabitants (1700 links): Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Trapuã and Adolfo. The first four systems are made of four primary facultative ponds and the last four by anaerobic ponds and secondary facultative ponds. A total of twenty-five chemical, physical and biological variables were analyzed in integrated samples collected between 24/05/2000 and 03/10/2000. The bathymetric analysis performed has indicated deadlines for sludge removal from the stabilization pond bottom. Mean sludge accumulation rates o btained for anaerobic and primary facultative ponds were 0.07 and 0.14 m3/inhabt.year, respectively. Effluents from anaerobic and facultative ponds had a mean pH of 6.6 and 7.4. In anaerobic ponds a righ rate of suspended solids removal was found and the Biochemical Oxygen Demand (BOD) had an overall general efficiency of 64% and 61%, respectively. The systems did not completely attend the present legislation in respect to a BOD removal of 80%, as required, however the mean value for the eight systems monitored was 78%, very close to the established limit. It is therefore suggested that for this region, in order to attain the removal efficiency of 80% anaerobic ponds should have a residence time of 5 days and the primary and secondary facultative ones should have residence times of 25 and 15 days respectively, coupled to loading rates of 140 and 170 Kg BOD/ha.day respectively. Also, the maximum limit of 1000 fecal coliforms per 100 ml was not reached, and in general there was a mean removal efficiency of 97.40%, indicating that an additional treatment process needs to be implemented for a successful removal of coliforms. No correlation was found between the removal efficiency and morphometry (length/weight) pond characteristics. Bad smell was present even in the absence of detectable amounts of sulfide. The mean efficiency for the removal of ammonium (NH4+), total nitrogen, total dissolved phosphorus and total phosphorus were 31%, 12%, 24%, and 27% respectively, among the systems studied.
46

Optimizing processes for biological nitrogen removal in Nakivubo wetland, Uganda

Kyambadde, Joseph January 2005 (has links)
The ability of Nakivubo wetland (which has performed tertiary water treatment for Kampala city for the past 40 years) to respond to pollution and to protect the water quality of Inner Murchison Bay of Lake Victoria was investigated. The aim of this study was to assess the capacity of Nakivubo wetland to remove nitrogen from the wastewater after its recent encroachment and modification, in order to optimize biological nitrogen removal processes using constructed wetland technology. Field studies were performed to assess the hydraulic loading, stability and water quality of this wetland. The distribution and activity of ammonium-oxidizing bacteria (AOB) in Nakivubo channel and wetland were also investigated, and the significance of the different matrices in biological nitrogen transformations within the two systems elucidated. Studies to optimize nutrient removal processes were carried out at pilot scale level both in container experiments and in the field using substrate-free constructed wetlands (CWs) planted with Cyperus papyrus and Miscanthidium violaceum which were adapted to the local ecological conditions. Results showed that Nakivubo wetland performs tertiary treatment for a large volume of wastewater from Kampala city, which is characterised by large quantities of nutrients, organic matter and to a lesser extent metals. Mass pollutant loads showed that wastewater effluent from a sewage treatment plant constituted a larger proportion of nitrogen and phosphorus and biochemical oxygen demand (BOD) discharged into the wetland. The upper section of Nakivubo wetland exhibited high removal efficiencies for BOD, whereas little or no ammonium-nitrogen and metals except Lead were removed by wetland. Studies further showed that nitrifying bacteria existed in the wetland but their activity was limited by oxygen depletion due to the high BOD in the wastewater and heterotrophic bacteria from the sewage treatment plant. Distributional studies indicated the presence of more AOB in surface sediments than the water column of the lower section of Nakivubo channel, an indication that nitrifiers settled with particulate matter prior to discharge into the wetland, and thus did not represent seeding of the wetland. The significant reductions in concentrations of BOD compared to ammonium and total nitrogen in the channel and wetland wastewater confirmed this finding. Whereas suspended nitrifiers upstream of Nakivubo channel equally influenced total nitrogen balance as those in surface sediments, epiphytic nitrification was more important than that of sediment/peat compartments in the wetland, and thus highlighted the detrimental impacts of wetland modification on the water quality Inner Murchison Bay and Lake Victoria as a whole. Performance assessment of pilot-scale container experiments and field-based CWs indicated highly promising treatment efficiencies, notably in papyrus-based treatments. Plant biomass productivity, nutrient storage, and overall system treatment performance were higher in papyrusbased constructed wetlands, and resulted in effluent that met national discharge limits. Thus, papyrus-based CWs were found to be operationally efficient in removing pollutants from domestic wastewater. / QC 20101028
47

A Mathematical Modeling Study On The Feasibility Of Disposing Partially Treated Domestic Wastewater Using Soil Pile Systems

Altinoklar, Hatice 01 July 2006 (has links) (PDF)
The soil pile system (SPS) is a wastewater infiltration system used for secondary and tertiary treatment of wastewater. The purpose of this study is to perform a feasibility study to assess the applicability of SPS for treatment and safe disposal of domestic wastewaters, using a simplistic steady-state flow analytical modeling and a numerical transient unsaturated flow and transport modeling approaches. It is also aimed to develop guidelines for the design and operation of field scale SPS using the results of modeling studies. The analytical modeling approach (AMA) was used to assess total coliform and chlorine attenuation efficiency in a SPS with clay loam soil. Analytical modeling results showed that SPS can treat wastewater in terms of total coliform and chlorine. Thus, in the light of findings of analytical modeling study, a pilot scale field study was conducted for the identifying the design and operational characteristics of a field scale system. Numerical modeling approach was used to evaluate the impact on contaminant removal of transient nature of wastewater infiltration and redistribution through clay loam soil pile. The results of numerical and analytical models were compared to assess the effect of flow regime on contaminant removal efficiencies. Results show that there is no significant difference between removal efficiencies achieved by numerical and analytical models. Whereupon, analytical model was used to assess behavior of SPS with different soil types, namely silt loam, loam, and sandy loam soils. Model results indicated that SPS can be effective reducing chlorine and total coliform concentrations of wastewater below discharge standards. Results also indicated that SPS is highly sensitive to soil thickness, infiltration rate, soil bulk density and most importantly decay rate coefficients and the performance of SPS is dependent on the design, construction, operation characteristics and soil-environmental conditions of the system.
48

Field Development and Performance Evaluation of a Constructed Wetland System in the Tropics

Hummel, Adelaide Pereira 08 November 2013 (has links)
This study is part of a project that was conducted by Florida International University (FIU), which designed, built, and characterized a constructed wetland (CW) wastewater treatment system in El Salvador, Central America. This study focuses on the detailed performance of a field-scale CW in the tropics, consisting of a subsurface flow wetland (SSF) and a surface flow wetland (SF). The SSF had a total area of 151.2 sq. m., filled with gravel and planted with Phragmites, Thalia, and Brachiaria, along three independent cells operating with a flow in parallel and receiving the influent domestic wastewater from a facultative lagoon and preceded the SF. The SF was a shallow open basin containing alternating regions of open water (195 sq. m. total) with submerged aquatic plants (Elodea) and regions of shallower water (605 sq. m. total) filled with emergent wetland vegetation (Typha, Thalia, and Cyperus). The design, construction, startup and operation phases of the field scale CW in that tropical setting are thus described with detail, including both SSF and SF characterization of influent and effluents. The SSF average hydraulic detention times during the wet and dry season were 2 days ± 0.9 days and 4 days ± 0.4 days, respectively; and the SF average hydraulic detention times during the wet and dry season were 20 days ± 11.1 days and 77 days ± 19.5 days, respectively. Brachiaria/Cyperus presented better results during the wet season with average BOD5 residuals of 36% ± 25%, and Thalia/Thalia during the dry season with average BOD5 residuals of 33% ± 22%. Phragmites/Typha presented better results during both seasons with average TSS residuals of 2% ± 3% (wet season), and 2% ± 2% (dry season). Residuals are also presented for COD, Oil & Grease, Total Fecal Coliform, Total Phosphorus, and Total Nitrogen. In addition, an assessment of the empirical models used in the design of the system is completed, having the EPA methodology as the preferred for BOD5 removal and three methodologies for TSS removal under tropical climate conditions. A comparison of the differences in treatment associated with each one of the selected plants and their combinations is also discussed. In summary, results strongly suggest that the CW system can effectively reduce contaminants in wastewater to levels that are comparable with the objective levels (i.e., secondary treatment levels).
49

Avaliação dos controles microbiológicos e do programa de redução de patógenos no abate de bovinos

Caselani, Kelly [UNESP] 12 June 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-12Bitstream added on 2014-06-13T20:16:21Z : No. of bitstreams: 1 caselani_k_me_jabo.pdf: 1897501 bytes, checksum: 58d7092f2bddb55a69e072e202d99cf8 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho teve por finalidade avaliar o resultado dos controles ambientais e operacionais, rotineiros e derivados do plano APPCC – Análise de Perigos e Pontos Críticos de Controle, aplicados ao abate de bovinos, e da pesquisa de microrganismos potencialmente patogênicos (Escherichia coli O157:H7, Salmonella enterica e Listeria monocytogenes). Com duração de um ano, a pesquisa foi desenvolvida em abatedouro-frigorífico habilitado à exportação localizado no Estado de São Paulo, Brasil. Foram analisadas 411 amostras ambientais para pesquisa de Listeria spp., 1.192 amostras de superfície de contato para a Contagem Bacteriana Total (CBT), 200, 100, 775, 264 e 100 amostras de superfície de carcaça para CBT, Coliformes totais, E. coli, Salmonella spp. e E. coli O157:H7, respectivamente, além de 256 amostras de recortes cárneos para a pesquisa de E. coli O157:H7. Os resultados evidenciaram condição higiênica aceitável para 51,1% das amostras ambientais de CBT, com 62,9% de amostras não aceitáveis no setor de abate. Um valor elevado de amostras (15,1%) foi positivo para Listeria spp. e para Listeria monocytogenes (4,6%). Observou-se que 89,6%, 2,8% e 7,6% das amostras de carcaça foram satisfatórias, aceitáveis e insatisfatórias para E. coli, respectivamente. Para a amostragem comparativa, 88,5% das amostras apresentaram-se satisfatórias para CBT, 84% para Coliformes Totais e 83,6% para E. coli. Nenhuma das amostras de carcaça analisadas foi positiva para Salmonella spp. ou para E. coli O157:H7. A frequência da ocorrência de E. coli O157:H7 em amostras de recortes cárneos (carne industrial) foi de 0,31%, com apenas uma amostra positiva / This study aimed to evaluate the result of the environmental and operational controls which are routine or derived from HACCP Plan - Hazard Analysis and Critical Control Points, applied to slaughter cattle, and potentially pathogenic microorganisms research (Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes). During one year, the research was developed in a slaughterhouse, enabled to export, located in the state of São Paulo, Brazil. We analyzed 411 environmental samples for Listeria spp. research, 1.192 samples of surface contact for Total Bacterial Count (TBC), 200, 100, 775, 264 and 100 samples of carcass surface for TBC, Total Coliform, E. coli, Salmonella spp. and E. coli O157:H7, respectively, besides 256 samples of meat cuts for E. coli O157:H7 research. The results showed that 51,1% of the environmental samples of TBC were in acceptable hygienic condition and 62,9% of samples were not acceptable in the slaughter industry. A high value of samples (15,1%) was positive for Listeria spp. and Listeria monocytogenes (4,6%). It was observed that 89,6%, 2,8% and 7,6% of the samples of carcass were satisfactory, acceptable and unsatisfactory for E. coli, respectively. For comparative sampling, 88,5% of the samples were satisfactory for TBC, 84% for Total Coliform and 83, 6% for E. coli. None of the samples of carcass tested was positive for Salmonella spp. or E. coli O157:H7. The frequency of the occurrence of E. coli O157:H7 in samples of meat cuts (meat industry) was 0,31%, with only one positive sample
50

Evaluation of Well Designs to Improve Access to Safe and Clean Water in Rural Tanzania

Kilungo, Aminata, Powers, Linda, Arnold, Nathan, Whelan, Kelli, Paterson, Kurt, Young, Dale 04 January 2018 (has links)
The objective of this study was to examine three well designs: drilled wells (20-30 m deep), closed dug wells (>5 m deep), and hand-dug open wells (<5 m deep), to determine the water quality for improving access to safe and clean water in rural communities. Heterotrophic plate count (HPC), total coliforms (TC), Escherichia coli (E. coli) and turbidity, were used to assess the water quality of 97 wells. Additionally, the study looked at the microflora diversity of the water, focusing on potential pathogens using outgrowth, PCR, and genome sequencing for 10 wells. Concentrations of TC for the open dug wells (4 x 10(4) CFU/100 mL) were higher than the drilled (2 x 10(3) CFU/100 mL) and closed dug wells (3 x 10(3) CFU/100 mL). E. coli concentration for drilled and closed dug wells was <22 MPN (most probable number)/100 mL, but higher for open wells (>154 MPN/100 mL). The drilled well turbidity (11 NTU) was within the standard deviation of the closed well (28 NTU) compared to open dug wells (49 NTU). Drilled and closed wells had similar microbial diversity. There were no significant differences between drilled and closed dug wells. The covering and lining of hand-dug wells should be considered as an alternative to improve access to safe and clean water in rural communities.

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