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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.
21

Kritická místa v českém jazyce na základní škole / Critical points in the Czech language at elementary school

Dygrínová, Gabriela January 2016 (has links)
The thesis deals with the critical points of teaching Czech language at the elementary school. The aim of the work was to identify the citical points of teaching Czech language to the sixth grade of the elementary level. The identification of the critical points was done through a qualitative analysis of the discussions lead with teachers of Czech language. The theoretical part of the work characterizes the Czech language curriculum in the sixth grade and its didactic apporoach in commonly used textbooks. Conceptions, such as the cricital point and the mistake are defined. The practical part of the work contains the analysis and the interpretation of the discussions carried out with the teachers. The program Altas.ti was used for the evaluation of the obtained data. The critical points of Czech language in the sixth grade of the elementary school were found to be the phenomena in the realm of syntax, morphology, and spelling. In the realm of syntax, the critical spots of the greatest weight were: the ability to think logically, the knowledge of the basic linguistic phenomena, the understanding of the syntactic relationships and the terminology. In morphology, the ability to distinguish between the parts of speech, the case determination, and the recognition of the number of the collective and the...
22

Pontos críticos no controle de insetos em equipamentos e estruturas de armazenagem de grãos / Critical points in the control of insects in equipment and structures of grains storage

Kessler, Moacir 27 July 2006 (has links)
Made available in DSpace on 2017-07-10T19:25:14Z (GMT). No. of bitstreams: 1 Moacir Kessler.pdf: 322336 bytes, checksum: 4b48bc8db4ae1af200ec7e3f622ff383 (MD5) Previous issue date: 2006-07-27 / This work had as objective to identify the critical points of insect control in structures of grain storage. The study was realized in the period of reception of the soy and maize harvest of 2006 in seven typical storing units of Western Paran? State. The presented data had been object of inspecting in the respective storing units during the reception of the harvest and aimed to identify the points inspected in the units; the presence of adult insects, the accumulation of residues, the difficulty of access to the place for cleanness, the lack of planning of the structure for the cleanness of the place and the lack of planning or of the project of the equipment aiming at its cleanness. The study proves that the inappropriateness of the installations and of the equipment is the cause of focus of infestation for insects, compromising the quality of the stored product beyond generating incidental costs to the storekeeper. The work objectified not only to present the critical points of insect control plague in the storage structures; as mainly to consider techniques of cleanness of the installations, of the equipment, to consider adjustments in the equipment and the installations being aimed at improvement in the cleanness and reduction or elimination of the deposited residues and consequent elimination of the focus of infestation, still considers changes in the projects of new storing units and equipment so that the same ones have a new concept in the conception of the projects and construction aiming the non deposition of residues, critical points of development of insects. / Este trabalho teve o objetivo de identificar os pontos críticos no controle de insetos em equipamentos e estruturas de armazenagem de grãos. O estudo foi realizado durante a recepção das safras de soja e milho de 2006, em sete unidades armazenadoras típicas da região oeste do Estado do Paraná. Os dados apresentados foram objeto de vistorias nas unidades armazenadoras no decorrer da recepção da safra e visou identificar nos pontos vistoriados nas unidades a presença de insetos adultos; o acúmulo de resíduos; a dificuldade de acesso ao local para limpeza; a falta de planejamento da estrutura para a limpeza do local e a falha de planejamento ou de projeto dos equipamentos ou da estrutura visando a sua limpeza. O estudo comprovou que a inadequação tanto das instalações como dos equipamentos é causa de foco de infestação por insetos, comprometendo a qualidade do produto armazenado além de gerar custos adicionais ao armazenador. O trabalho objetivou também sugerir a adoção de técnicas de limpeza das instalações, dos equipamentos, propor ajustes nos equipamentos e nas instalações, visando melhoria na limpeza e a eliminação dos resíduos depositados e conseqüente redução dos focos de infestação; propõe ainda alteração nos projetos de novas unidades armazenadoras e equipamentos a fim de que os mesmos tenham um novo conceito na concepção dos projetos e construção, visando a não deposição de resíduos, pontos críticos de desenvolvimento de insetos. Nos resultados das inspeções realizadas nas instalações das unidades armazenadoras foram constatados diversos pontos críticos de controle de pragas em suas instalações e equipamentos. Ficou demonstrando também que as condições das unidades armazenadoras pesquisadas e atualmente destinadas ao beneficiamento de cereais, carecem de uma série de providências para não permitir a deposição de resíduos e a conseqüente proliferação de insetos; sendo que as novas instalações dever ter seus projetos melhor elaborados a fim de que não se permita pontos críticos de deposição de resíduos para o desenvolvimento de pragas.
23

Pontos críticos no controle de insetos em equipamentos e estruturas de armazenagem de grãos / Critical points in the control of insects in equipment and structures of grains storage

Kessler, Moacir 27 July 2006 (has links)
Made available in DSpace on 2017-05-12T14:48:39Z (GMT). No. of bitstreams: 1 Moacir Kessler.pdf: 322336 bytes, checksum: 4b48bc8db4ae1af200ec7e3f622ff383 (MD5) Previous issue date: 2006-07-27 / This work had as objective to identify the critical points of insect control in structures of grain storage. The study was realized in the period of reception of the soy and maize harvest of 2006 in seven typical storing units of Western Paran? State. The presented data had been object of inspecting in the respective storing units during the reception of the harvest and aimed to identify the points inspected in the units; the presence of adult insects, the accumulation of residues, the difficulty of access to the place for cleanness, the lack of planning of the structure for the cleanness of the place and the lack of planning or of the project of the equipment aiming at its cleanness. The study proves that the inappropriateness of the installations and of the equipment is the cause of focus of infestation for insects, compromising the quality of the stored product beyond generating incidental costs to the storekeeper. The work objectified not only to present the critical points of insect control plague in the storage structures; as mainly to consider techniques of cleanness of the installations, of the equipment, to consider adjustments in the equipment and the installations being aimed at improvement in the cleanness and reduction or elimination of the deposited residues and consequent elimination of the focus of infestation, still considers changes in the projects of new storing units and equipment so that the same ones have a new concept in the conception of the projects and construction aiming the non deposition of residues, critical points of development of insects. / Este trabalho teve o objetivo de identificar os pontos críticos no controle de insetos em equipamentos e estruturas de armazenagem de grãos. O estudo foi realizado durante a recepção das safras de soja e milho de 2006, em sete unidades armazenadoras típicas da região oeste do Estado do Paraná. Os dados apresentados foram objeto de vistorias nas unidades armazenadoras no decorrer da recepção da safra e visou identificar nos pontos vistoriados nas unidades a presença de insetos adultos; o acúmulo de resíduos; a dificuldade de acesso ao local para limpeza; a falta de planejamento da estrutura para a limpeza do local e a falha de planejamento ou de projeto dos equipamentos ou da estrutura visando a sua limpeza. O estudo comprovou que a inadequação tanto das instalações como dos equipamentos é causa de foco de infestação por insetos, comprometendo a qualidade do produto armazenado além de gerar custos adicionais ao armazenador. O trabalho objetivou também sugerir a adoção de técnicas de limpeza das instalações, dos equipamentos, propor ajustes nos equipamentos e nas instalações, visando melhoria na limpeza e a eliminação dos resíduos depositados e conseqüente redução dos focos de infestação; propõe ainda alteração nos projetos de novas unidades armazenadoras e equipamentos a fim de que os mesmos tenham um novo conceito na concepção dos projetos e construção, visando a não deposição de resíduos, pontos críticos de desenvolvimento de insetos. Nos resultados das inspeções realizadas nas instalações das unidades armazenadoras foram constatados diversos pontos críticos de controle de pragas em suas instalações e equipamentos. Ficou demonstrando também que as condições das unidades armazenadoras pesquisadas e atualmente destinadas ao beneficiamento de cereais, carecem de uma série de providências para não permitir a deposição de resíduos e a conseqüente proliferação de insetos; sendo que as novas instalações dever ter seus projetos melhor elaborados a fim de que não se permita pontos críticos de deposição de resíduos para o desenvolvimento de pragas.
24

A Computational Study Of Nucleophilic Attacks In Organometallic Complexes

Dinda, Shrabani 12 1900 (has links) (PDF)
A wide variety of computational methods are available for exploring molecular structures and reactivity in chemistry. These range from molecular mechanics calculations allowing determination of the geometry of a molecule to ab initio calculations for the electronic structure of compounds. Electronic structure calculations can be carried out with sufficient rigor so that the results are now comparable with experimental results in many cases. Density Functional Theory (DFT) with hybrid functional like B3LYP, for example, is very popular especially for studies on organometallic molecules and their reactions. Traditional ab initio approaches including Hartree-Fock (HF) and post-HF methods that include configuration interaction, such as MP2 and MP4 continue to be used, often for comparison with DFT based methods. Semi-empirical methods now appear to have only limited use except in large systems, in combination with molecular mechanics (MM) calculations. A relatively new use of MM for large systems is in hybrid calculations where the reactive center of the system is treated at a higher level leaving the remainder to be treated at the MM level. These hybrid QM/MM (quantum mechanics/molecular mechanics) calculations, such as ONIOM (our own n-layered integrated molecular orbital and molecular mechanics developed by Morokuma and co-workers) enable one to treat the steric bulk of the big system effectively and computationally efficiently. They appear to be very standard methods particularly in studies relating to reactions of organometallic systems and structures of large biomolecules. A short description of these methods is given below. • ab initio: a wide variety of programs that calculate the electronic structure of molecules using the Schrödinger equation, the values of the fundamental constants and the atomic numbers of the atoms present (Atkins, 1991). Molecular structures, optimized as a function of the electronic structure, are valuable starting points for many studies. • Density Functional Theory (DFT): a theoretical model in which the energy of an N-electron system is described as a functional of the density. • Semi-empirical techniques use approximations to evaluate the overlap, repulsion and exchange integrals in solving the Schrodinger equation. Often, these integrals are not evaluated but estimated to reproduce experimental data. • Molecular mechanics uses classical physics to explain and interpret the behavior of atoms and molecules. • Molecular dynamics (MD): Newton’s laws of motion are used to examine the time-dependent behavior of systems, including vibrations and Brownian motion, using a classical mechanical description. When combined with DFT, it leads to the Car-Parrinello method. • QM/MM method: It is a molecular simulation method that combines the strength of both QM (accuracy) and MM (speed) calculations, thus resulting in an extremely powerful tool for the study of bigger systems like chemical process in solution, interaction of drugs with biomolecules etc. Several commercial and educational packages in computational chemistry include a suite of programs that enable study of organic and organometallic molecules in an integrated fashion. While no list can be comprehensive, those that are more popular and useful are listed in several websites URL (http://www.ccl.net/chemistry/links/software/index.shtml). In the early days of computational chemistry up to 1980's, detailed studies were only carried out on small organic compounds or empirical studies were carried out on transition metal containing organometallics. However, in recent times, significant advancements in theoretical methods and computer capability (hardware and software), have led to the acceleration of theoretical and computational studies of complex systems including compounds containing transition metal elements. Computational and theoretical studies of organometallic complexes and their reactions have gained immense popularity and the numbers of papers including theoretical studies are dramatically increasing. One reason for this popularity is that organometallic complexes exhibit unusual geometries, bonding, and reactivity which often do not fall into the domain of inorganic or organic chemistry making them difficult to understand. Catalysis is one of the most extensively studied areas in organometallic chemistry where computational studies already make a real and valuable contribution to the analysis and interpretation of experimental data. However, what might be called ‘in silico’ catalyst screening and design, has rarely been achieved. One might say that successful prediction of catalyst performance is still a dream. A recent review summarizes the current state of the art in computational chemistry as applied to organometallic catalysis, covering both calculated ligand property descriptors and mechanistic studies of catalytic cycles.1 Some of the widely studied catalytic reactions of current interest, that provide huge scope for computational and theoretical analysis, are allylic alkylation (Pd),2 hydrogenation (Rh),3 hydroformylation (Rh),4 alkene metathesis (Ru),5 cross-coupling (Pd),6 C–H activation (Pd)7 and amination (Pd).8 There are many more examples where computational studies appear to be very useful for analysis of crystal structures and NMR structures or prediction of structures where no experimental data are available for complicated organometallic systems. There are a number of studies on drug-DNA/nucleobases interactions using QM/MM-MD simulations where people have investigated the interactions of metal complexes with double stranded (ds) DNA/nucleobases and the effects of their binding on the local and the global structure of DNA. QM/MM methods are also very helpful for studying catalytic reactions, interpretation of structure of large systems (proteins) and understanding reactions in biological systems. Scope of the Thesis In this thesis an attempt is made to use computational chemistry to understand organometallic reactions that are of significance from biological and synthetic view points, such as the action of organometallic complexes on DNA and the mechanism of some catalytic reactions. In many of these cases, the key step involved a nucleophillic attack. Specifically four such problems have been addressed where experimental results are not sufficient to provide a complete mechanistic picture of the reaction. Hence, the thesis contains four chapters with each having an independent brief introduction. The first chapter deals with the substitution reaction where water replaces chloride ion in the piano stool type ruthenium (II)-arene complexes and subsequently coordination of Ru to guanine/adenine occurs in these complexes. These steps have been studied using density functional theory at the B3LYP level. The complexes have promising anticancer activity. These nucleophilic substitution reactions are very important for activating these complexes so that they can interact with DNA, because DNA is thought to be primary target for their anticancer activity. In this chapter, both associative and dissociative pathways have been explored in the gas phase, as well as in the presence of other solvents for substitution reactions. Among the associative paths, a variety of possibilities can exist for the hydrolysis based on the direction of the nucleophilic attack by a water molecule. The proposed theoretical model for hydrolysis provides new insight into the hydrolysis process in half sandwich ruthenium complexes. The second chapter deals with the QM/MM calculations to investigate the structural and electronic properties of drug-DNA interactions, where DNA acts as nucleophile towards the metal complex. A series of piano-stool type ruthenium (II)-arene complexes were selected for the present study. These interactions were analyzed using the two layer ONIOM method. The importance of this study lies in the detailed understanding of factors that govern DNA binding and reactivity which is clearly of great pharmacological interest, as it may provide the basis for designing better anticancer agents. Experimental results that explore the structural feature of DNA-metal complexes at a molecular level are very limited. Thus theoretical calculations of molecular and electronic structure represent a valuable complement to experiments. They provide an alternative way to explore structure-activity relationships, and the drug binding mechanism, in detail. The third chapter reports the use of QM/MM methods in understanding the reaction mechanism and enantioselectivity in an organic transformation. In this section, a computational investigation of the enantioselectivity observed in the allylation of cinnamaldehyde, catalyzed by chiral platinum phosphinite complexes, have been carried out. The catalysts are ascorbic acid based phosphinite complexes where enantioselectivity depends on the substitution of benzyl groups on the chiral phosphinite ligands. From the experiment, it is not clear how the effect of an ancillary ligand can make such a big impact on enantioselectivity. To find out the origin of stereoselectivity, a computational study was taken up. A reaction mechanism was established where the nucleophilic attack determines the rate of the reaction and the corresponding enantioselectivity. A screening process has been utilized to select relevant reactant adducts and corresponding transition states from approximately 200 theoretically possible conformers using MM calculations. Finally with the help of QM/MM calculations, the numbers of contributions of these conformers were estimated. This approach correctly predicts the enantioselectivity in these reactions catalyzed by these complexes especially when the experimental enantioselectivity is very high. The fourth chapter of the thesis discusses the use of computational techniques to study the nucleophilic attack of an imine on a Ti-olefin complex. The reaction of Grignard reagents with imines mediated by stoichiometric amounts of titanium isopropoxide has been reported recently. On the basis of deuterium labeling experiments, nucleophilic attack of an imine on a Ti-olefin complex was believed to be a key step. Effect of deuterium labeling on the ratio of products formed is not easy to understand from experiments. Hence a computational study was performed using the DFT method to establish the mechanism of substitution and to understand the role of deuterium labeling. The thesis also includes a study of Cu-Cu interactions using Atoms in Molecules (AIM) theory in copper complexes with reasonably short Cu-Cu distances. The concept of bond critical points (BCP) from AIM analysis is employed to investigate the CuI-CuI bonding interactions in ligand unsupported copper complexes where the CuI-CuI contacts are shorter than the sum of their van der Waals radii. There is extensive debate about the nature of interactions between d10 "closed shell" systems in copper (CuI) complexes, which is known as cuprophilicity. In this study, an attempt has been made to compute the electron density between the two CuI centers and examine the nature of this “interaction”. As this falls outside the main theme of nucleophilic interactions in metal complexes, it has been relegated to an appendix.
25

Nature Of Criticality, Structuring, And Phase Behavior Of Complex Fluids

Bagchi, Debjani 09 1900 (has links)
This thesis is mainly concerned with some important properties of complex fluids, and how these properties are influenced by structures in the nano/mesoscopic scale. Short-range assembly of the constituent molecules results in an amazing variety of phase behavior in these systems. Liquid-liquid phase transitions, or transitions from a homogeneous(mixed) phase to an immiscible phase (two-phase coexistence), are the outcome of a competition between entropy and short-ranged attractive forces, and form an important part of this thesis. A rich phase behavior is uncovered by a detailed study of liquid-liquid phase transitions in a mixture of ethanol(E) and water(W), induced by the addition of ammonium sulfate(AS) ions (E and W are otherwise completely soluble in each other). This is the main motivation for choosing this system. Furthermore, experimental evidence of the presence of supramolecular association in alcohol-water mixtures [J.-H. Guo et al., Phys. Rev Lett, 91, 15401(2003)] enhances our interest to study the phase behavior in more detail. The presence of a critical point, at which there is a second order phase transition, is quite common in complex fluids. An issue which has been the subject of extensive scientific research in recent years is the influence of nano/mesoscopic structure on the critical behavior of these fluids corresponds to the Ising universality class. However, the approach to the asymptotic regime is governed by a competition between the correlation length of critical concentration fluctuations and the additional length scale arising due to structuring., which results in a crossover from the universal Ising behavior to the mean-field behavior, sometimes within the critical domain. This phenomenon of crossover criticality is presently explored in the E + W + AS system. A significant portion of the thesis presents explorations on the critical behavior in the vicinity of special critical points (SCP), which are formed by the coalescence of two or more critical points. Recentrant liquid-liquid phase transitions observed in the E + W + AS system, furnishes an unique opportunity for the realization of three SCPs – the double critical point(DCP) and the critical double point(CDP) formed by the merger of two critical points , and a critical inflection point(CIP), formed by the merger of three critical points. A CIP had not been experimentally realized prior to the studies presented in this thesis. Apart from the above studies investigations are also carried out on the conformational changes of a technologically important conducting polymer, polyethylene dioxythiophene doped with polystyrene suflonate (PEDOT-PSS), in various solvents. The electrical and optical properties of the polymer films get enhanced when solution processed with specific solvents. The experiments presented in this thesis are directed at unraveling the role of conformational modifications in the electrical and optical properties of these systems. The experimental techniques that were employed in the present studies are: Laser light scattering, small-angle X-ray scattering(SAXS) measurements and visual observations. The eoexistence surface of the system E + W + AS was determined by visual observations. Laser light scattering measurements were conducted to study the critical behavior of osmotic susceptibility (xr) of E + W + As, whereas SAXS studies were conducted to ascertain the existence, and quantify the spatial extent of the additional length scale in the two systems investigated. The main objectives of this research were: (i) to study the phase behavior of the ternary mixture E + W + AS at atmospheric pressure; (ii) to check the existence of crossover from 3-D Ising to mean-field critical behavior while moving away from Tc in this system; (iii) to determine the nature (monotonic or nonmonotonic) of crossover; (iv) to provide some insight into the origin of this crossover behavior in terms of an additional length scale characteristic of the system; (v) to understand the evolution of the critical behavior in the proximity of CDP, and DCP; (vi) to experimentally realize the CIP; and (vii) to investigate the presence of solvent-induced conformational changes in conducting polymer.
26

Avaliação de pontos de contaminação por Salmonella sp. e coliformes totais durante o preparo de dietas para suínos

Pellegrini, Débora da Cruz Payão January 2012 (has links)
A presença de Salmonella é uma das mais importantes barreiras sanitárias à exportação de alimentos. A ração contaminada representa potencial fonte de introdução de Salmonella nos rebanhos suínos, além do risco indireto de infecção ao consumidor. Um estudo transversal conduzido em quatro fábricas de ração teve como objetivos avaliar a frequência de isolamento de Salmonella e coliformes totais nestas unidades, verificar a presença desses agentes nas diversas etapas do processo de produção, correlacionar grupos clonais de Salmonella sp. obtidos pela análise de macrorestrição associada à eletroforese em campo pulsado (PFGE), além de avaliar a concordância entre o escore obtido na aplicação de roteiro de inspeção da Instrução Normativa (IN) 4 do Ministério da Agricultura e Abastecimento e os níveis de coliformes totais encontrados. De 1.269 amostras analisadas, sessenta e três (4,96%) apresentaram Salmonella sp. e 38,53% (n=489) apresentaram presença de enterobactérias. As freqüências de contaminação por Salmonella nas quatro fábricas avaliadas (A, B, C e D) foram, respectivamente, 3,5% (n=11/317), 1,7% (n=5/289), 7,1% (n=23/308) e 7% (n=25/355). Já para coliformes totais foram, respectivamente, 40,7% (129/317), 30,1% (87/289), 52,6% (162/308) e 31,3% (111/355). Nas fábricas A e D, Salmonella foi detectada em amostras de produto final. Estirpes apresentando genótipos semelhantes foram identificadas nos sorovares Orion, Montevideo, Worthington e Agona. Foi possível verificar que o sorovar Montevideo obteve o maior número de grupos clonais, apresentando pulsotipos distribuídos entre ingredientes, poeira, equipamentos e ração. O isolamento de Salmonella foi significativamente mais frequente (p =0,002) em amostras com a presença (36/489; 7,36%) do que com ausência de coliformes totais (27/780; 3,46%). As contagens logarítmicas médias encontradas de coliformes totais, considerando todas as amostras analisadas por fábrica, foram: A: 0,97 (IC 95%: 0,81-1,13); B: 0,78 (IC 95%: 0,61-0,94); C: 1,32 (IC 95%: 1,16-1,49) e D: 0,91 (IC 95%: 0,75-1,06). Constatou-se elevada variabilidade no número de coliformes totais em todos os pontos amostrados nas quatro fábricas, e não houve diferenças significativas entre os pontos amostrados e entre as fábricas (p=0,174). A regressão logística tendo como variável resposta a presença de coliformes totais apontou maiores razão de chance (OR) de isolamento no transportador (OR=3,67; IC 95%: 2,28-5,89), dosagem (OR=9,51, IC 95%: 4,43-20,41), moagem (OR=7,1; IC 95%: 3,27-15,40), mistura (OR=4,08; IC 95%: 2,04-8,17), poeira (OR=3,50; IC 95%:2,10-5,84), resíduos (OR=6,22; IC 95%: 3,88-9,95) e fábrica C (OR=2,43; IC 95%: 1,68-3,53). Da mesma forma, o transportador (OR= 4,43; IC95%: 2,43-8,09) foi o local com maior probabilidade de isolamento de Salmonella, seguidos da poeira coletada nas dependências da fábrica (OR=2,88; IC95%: 1,41-5,88). Comparadas à fábrica B, as unidades C e D apresentaram, respectivamente, 2,74 e 2,83 mais chances de isolamento de Salmonella. Ao analisar os 128 itens necessários no Roteiro de Inspeção da IN4, a fábrica B obteve o menor número de não conformidades. Nas demais fábricas, as maiores inconformidades foram encontradas quanto à estrutura da área interna e externa das fábricas. As fábricas A e D foram as que apresentaram o maior número de itens não conformes relacionados à limpeza e higienização de equipamentos. Entre os 29 itens imprescindíveis na Avaliação de Estabelecimento e Procedimentos Operacionais Padrão, oito não foram cumpridos em pelo menos uma das fábricas. A fábrica B apresentou todos os itens em conformidade, ao passo que as fábricas A e D não cumpriram os oito itens. A fábrica C apresentou três itens não conformes, relacionados à limpeza de piso e parede, recepção e armazenamento de matérias-primas. Não houve concordância entre os escores obtidos no roteiro de avaliação e a média de coliformes totais encontrada nas fábricas, demonstrando que apenas a adequação à legislação pode não garantir a inocuidade do alimento produzido. A partir disso, conclui-se que é necessário implantar programas de monitoramento e controle microbiológico ao longo da linha de produção, independente da situação da fábrica em relação à legislação vigente. A elaboração e produção de equipamentos de fácil limpeza e com mínimo acúmulo de poeira e resíduos deve ser incluída nos programas de controle de Salmonella concomitante às demais medidas de controle preconizadas. / The presence of Salmonella is one of the most important sanitary barriers to food exports. The contaminated feed is a potential source of introduction of Salmonella in pig herds, and may also represent a risk to the consumer. A cross-sectional study conducted in four feed mills was carried out to evaluate the frequency of isolation of enterobacteria and Salmonella at various stages of feed production, to identify clonal groups of Salmonella sp. Obtained by macrorestriction analysis associated with pulsed field gel electrophoresis (PFGE), and to verify the association between the score obtained by feed mills after the application of the checklist of the Normative 4 (IN4) of the Ministry of Agriculture and Food Supply and the mean of total coliforms found in the unit. Among 1,269 samples analysed, sixty-three (4.96%) showed the presence of Salmonella. The four feeds mills evaluated (A, B, C and D) presented, respectively, 3,5% (n=11/317), 1.7% (n=5/289), 7,1% (n=23/308), and 7% (n=25/355) of positive samples. Total coliforms were isolated from 40.7% (129/317), 30.1% (87/289), 52.6% (162/308) e 31.3% (111/355) samples taken at unit A, B, C and D, respectively. In the units A and D, Salmonella was detected in samples of feed. Strains showing similar genotypes have been identified as Serovar Orion, Montevideo, Worthington and Agona. Serovar Montevideo presented the highest number of clonal groups, with common pulsotypes distributed among ingredients, dust, equipment and feed. The isolation of Salmonella was significantly higher (p=0,002) in samples with the presence of total coliforms (36/489; 7.36%) than in the negative ones (27/780; 3.46%). The mean logarithmic counts of total coliforms considering all samples were determined for each plant: A: 0.97 (95% CI: 0.81 to 1.13), B: 0.78 (95% CI: 0.61 to 0.94), C: 1.32 (95% CI: 1.16 to 1.49) and D: 0.91 (95% CI: 0.75 to 1.06). A high variability on the number of total coliforms in all the sampled points was found in all feed mills, and there was no statistical diference between the sampling sites and units (p=0.174). The logistic regression, with isolation of total coliforms as the response variable, showed a high odds ratio (OR) of isolation from conveyors (OR = 3.67, 95% CI: 2.28 to 5.89), dosing (OR = 9.51, 95% CI: 4.43 to 20.41), grinding (OR = 7.10, 95% CI = 3.27 to 15.40), mixing (OR = 4.08, 95 % CI: 2.04 to 8.17), dust (OR = 3.50, 95% CI: 2.10 to 5.84), crusts (OR = 6.22, 95% CI: 3.88 to 9.95) and unit C (OR = 2.43, 95% CI: 1.68 to 3.53). The conveyors (OR = 4.43, 95% CI: 2.43-8.09) were the most likely sites of isolation of Salmonella, followed by the dust collected on the premises of the plant (OR = 2.88, 95% CI: 1.41-5.88). Feed mills C and D showed, respectively, 2.74 and 2.83 higher odds for Salmonella isolation than feed mill B. The verification of the 128 items addressed on the Guidelines for Inspection of Normative 4 (IN 4) of the Brazilian Ministry of Agriculture and Food Supply pointed out that factory B had the lowest number of nonconformities. The other three feed mills, presented most faults related to the physical structure of the facilities. Feed mills A and D presented the largest number of nonconformities related to cleaning and sanitizing of equipment. Among the 29 mandatory items in IN4, eight were not met in at least one of the factories. Feed mill B presented all items accordingly, while plants A and D did not meet any of the eight items. Feed mill C had three non-compliant items related to the floor and wall cleaning, reception and storage of raw materials. There was no association between the score obtained on the inspection checklist and the level of total coliforms found in the sampled units, demonstrating that only the compliance to the legislation cannot guarantee the safety of feed produced. It was concluded that programs for monitoring and control microbial contamination throughout the production line are needed, regardless of the status of the plant in the relation to the current legislation.The design of equipment that allow easy cleaning and with minimal accumulation of dust and debris should be added to other measures in Salmonella control programs.
27

Multiplicidade de soluções positivas para algumas classes de problemas elípticos em R2 com condição de Neumann

Oliveira, Elisânia Santana de 05 March 2012 (has links)
Made available in DSpace on 2015-05-15T11:46:03Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 952913 bytes, checksum: 0b170d0ebe538db0d58bb1162fc18e99 (MD5) Previous issue date: 2012-03-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we prove the existence and multiplicity of positive weak solutions for some classes of elliptic problems in plane involving exponential growth of the Trudinger-Moser type with Neumann boundary condition. To do this, we use the method of sub and supersolution in combination with variational methods and the maximum principle. / Nesta dissertação, provamos a existência e multiplicidade de soluções fracas positivas para algumas classes de problemas elípticos no plano envolvendo crescimento exponencial do tipo Trudinger-Moser com condição de Neumann na fronteira. Para isso, usaremos o método de sub e supersolução em combinação com métodos variacionais e o princípio do máximo.
28

Vztah rodiny a školy: případ dítěte mezi institucemi v konfliktu / Communication between family and school: The case of a child between institutions in conflict

Machová, Natálie January 2018 (has links)
The main goal of this diploma thesis is to map out the area of communication and cooperation between the pupil's parents and school in a conflict situation. At the same time, this thesis examines the impact of said situation on the optimal development of the child, who is in conflicting posture against the two institutions. The theoretical part is devoted to introducing the basic functioning of family and school, its mutual relations and forms of contact between the two institutions. It also illuminates the possible modes of cooperation between parents and school and possible conflicts arising from the relationship. Theoretical framework is focused on the child at the start of compulsory education and his main developmental tasks during the primary school age. The main focus of the thesis is the empirical part, undertaken in the framework of quantitative methodological approach. The case study focuses on a pupil and the critical points of conflict among the school and family as institutions and the child between them. Using analysis of documents, semi-structured interviews and observations, the complicated relationship of particular family and school was researched, and as well the impact of the relations on the development of the child. The findings suggest, that ineffective cooperation and...
29

Avaliação de pontos de contaminação por Salmonella sp. e coliformes totais durante o preparo de dietas para suínos

Pellegrini, Débora da Cruz Payão January 2012 (has links)
A presença de Salmonella é uma das mais importantes barreiras sanitárias à exportação de alimentos. A ração contaminada representa potencial fonte de introdução de Salmonella nos rebanhos suínos, além do risco indireto de infecção ao consumidor. Um estudo transversal conduzido em quatro fábricas de ração teve como objetivos avaliar a frequência de isolamento de Salmonella e coliformes totais nestas unidades, verificar a presença desses agentes nas diversas etapas do processo de produção, correlacionar grupos clonais de Salmonella sp. obtidos pela análise de macrorestrição associada à eletroforese em campo pulsado (PFGE), além de avaliar a concordância entre o escore obtido na aplicação de roteiro de inspeção da Instrução Normativa (IN) 4 do Ministério da Agricultura e Abastecimento e os níveis de coliformes totais encontrados. De 1.269 amostras analisadas, sessenta e três (4,96%) apresentaram Salmonella sp. e 38,53% (n=489) apresentaram presença de enterobactérias. As freqüências de contaminação por Salmonella nas quatro fábricas avaliadas (A, B, C e D) foram, respectivamente, 3,5% (n=11/317), 1,7% (n=5/289), 7,1% (n=23/308) e 7% (n=25/355). Já para coliformes totais foram, respectivamente, 40,7% (129/317), 30,1% (87/289), 52,6% (162/308) e 31,3% (111/355). Nas fábricas A e D, Salmonella foi detectada em amostras de produto final. Estirpes apresentando genótipos semelhantes foram identificadas nos sorovares Orion, Montevideo, Worthington e Agona. Foi possível verificar que o sorovar Montevideo obteve o maior número de grupos clonais, apresentando pulsotipos distribuídos entre ingredientes, poeira, equipamentos e ração. O isolamento de Salmonella foi significativamente mais frequente (p =0,002) em amostras com a presença (36/489; 7,36%) do que com ausência de coliformes totais (27/780; 3,46%). As contagens logarítmicas médias encontradas de coliformes totais, considerando todas as amostras analisadas por fábrica, foram: A: 0,97 (IC 95%: 0,81-1,13); B: 0,78 (IC 95%: 0,61-0,94); C: 1,32 (IC 95%: 1,16-1,49) e D: 0,91 (IC 95%: 0,75-1,06). Constatou-se elevada variabilidade no número de coliformes totais em todos os pontos amostrados nas quatro fábricas, e não houve diferenças significativas entre os pontos amostrados e entre as fábricas (p=0,174). A regressão logística tendo como variável resposta a presença de coliformes totais apontou maiores razão de chance (OR) de isolamento no transportador (OR=3,67; IC 95%: 2,28-5,89), dosagem (OR=9,51, IC 95%: 4,43-20,41), moagem (OR=7,1; IC 95%: 3,27-15,40), mistura (OR=4,08; IC 95%: 2,04-8,17), poeira (OR=3,50; IC 95%:2,10-5,84), resíduos (OR=6,22; IC 95%: 3,88-9,95) e fábrica C (OR=2,43; IC 95%: 1,68-3,53). Da mesma forma, o transportador (OR= 4,43; IC95%: 2,43-8,09) foi o local com maior probabilidade de isolamento de Salmonella, seguidos da poeira coletada nas dependências da fábrica (OR=2,88; IC95%: 1,41-5,88). Comparadas à fábrica B, as unidades C e D apresentaram, respectivamente, 2,74 e 2,83 mais chances de isolamento de Salmonella. Ao analisar os 128 itens necessários no Roteiro de Inspeção da IN4, a fábrica B obteve o menor número de não conformidades. Nas demais fábricas, as maiores inconformidades foram encontradas quanto à estrutura da área interna e externa das fábricas. As fábricas A e D foram as que apresentaram o maior número de itens não conformes relacionados à limpeza e higienização de equipamentos. Entre os 29 itens imprescindíveis na Avaliação de Estabelecimento e Procedimentos Operacionais Padrão, oito não foram cumpridos em pelo menos uma das fábricas. A fábrica B apresentou todos os itens em conformidade, ao passo que as fábricas A e D não cumpriram os oito itens. A fábrica C apresentou três itens não conformes, relacionados à limpeza de piso e parede, recepção e armazenamento de matérias-primas. Não houve concordância entre os escores obtidos no roteiro de avaliação e a média de coliformes totais encontrada nas fábricas, demonstrando que apenas a adequação à legislação pode não garantir a inocuidade do alimento produzido. A partir disso, conclui-se que é necessário implantar programas de monitoramento e controle microbiológico ao longo da linha de produção, independente da situação da fábrica em relação à legislação vigente. A elaboração e produção de equipamentos de fácil limpeza e com mínimo acúmulo de poeira e resíduos deve ser incluída nos programas de controle de Salmonella concomitante às demais medidas de controle preconizadas. / The presence of Salmonella is one of the most important sanitary barriers to food exports. The contaminated feed is a potential source of introduction of Salmonella in pig herds, and may also represent a risk to the consumer. A cross-sectional study conducted in four feed mills was carried out to evaluate the frequency of isolation of enterobacteria and Salmonella at various stages of feed production, to identify clonal groups of Salmonella sp. Obtained by macrorestriction analysis associated with pulsed field gel electrophoresis (PFGE), and to verify the association between the score obtained by feed mills after the application of the checklist of the Normative 4 (IN4) of the Ministry of Agriculture and Food Supply and the mean of total coliforms found in the unit. Among 1,269 samples analysed, sixty-three (4.96%) showed the presence of Salmonella. The four feeds mills evaluated (A, B, C and D) presented, respectively, 3,5% (n=11/317), 1.7% (n=5/289), 7,1% (n=23/308), and 7% (n=25/355) of positive samples. Total coliforms were isolated from 40.7% (129/317), 30.1% (87/289), 52.6% (162/308) e 31.3% (111/355) samples taken at unit A, B, C and D, respectively. In the units A and D, Salmonella was detected in samples of feed. Strains showing similar genotypes have been identified as Serovar Orion, Montevideo, Worthington and Agona. Serovar Montevideo presented the highest number of clonal groups, with common pulsotypes distributed among ingredients, dust, equipment and feed. The isolation of Salmonella was significantly higher (p=0,002) in samples with the presence of total coliforms (36/489; 7.36%) than in the negative ones (27/780; 3.46%). The mean logarithmic counts of total coliforms considering all samples were determined for each plant: A: 0.97 (95% CI: 0.81 to 1.13), B: 0.78 (95% CI: 0.61 to 0.94), C: 1.32 (95% CI: 1.16 to 1.49) and D: 0.91 (95% CI: 0.75 to 1.06). A high variability on the number of total coliforms in all the sampled points was found in all feed mills, and there was no statistical diference between the sampling sites and units (p=0.174). The logistic regression, with isolation of total coliforms as the response variable, showed a high odds ratio (OR) of isolation from conveyors (OR = 3.67, 95% CI: 2.28 to 5.89), dosing (OR = 9.51, 95% CI: 4.43 to 20.41), grinding (OR = 7.10, 95% CI = 3.27 to 15.40), mixing (OR = 4.08, 95 % CI: 2.04 to 8.17), dust (OR = 3.50, 95% CI: 2.10 to 5.84), crusts (OR = 6.22, 95% CI: 3.88 to 9.95) and unit C (OR = 2.43, 95% CI: 1.68 to 3.53). The conveyors (OR = 4.43, 95% CI: 2.43-8.09) were the most likely sites of isolation of Salmonella, followed by the dust collected on the premises of the plant (OR = 2.88, 95% CI: 1.41-5.88). Feed mills C and D showed, respectively, 2.74 and 2.83 higher odds for Salmonella isolation than feed mill B. The verification of the 128 items addressed on the Guidelines for Inspection of Normative 4 (IN 4) of the Brazilian Ministry of Agriculture and Food Supply pointed out that factory B had the lowest number of nonconformities. The other three feed mills, presented most faults related to the physical structure of the facilities. Feed mills A and D presented the largest number of nonconformities related to cleaning and sanitizing of equipment. Among the 29 mandatory items in IN4, eight were not met in at least one of the factories. Feed mill B presented all items accordingly, while plants A and D did not meet any of the eight items. Feed mill C had three non-compliant items related to the floor and wall cleaning, reception and storage of raw materials. There was no association between the score obtained on the inspection checklist and the level of total coliforms found in the sampled units, demonstrating that only the compliance to the legislation cannot guarantee the safety of feed produced. It was concluded that programs for monitoring and control microbial contamination throughout the production line are needed, regardless of the status of the plant in the relation to the current legislation.The design of equipment that allow easy cleaning and with minimal accumulation of dust and debris should be added to other measures in Salmonella control programs.
30

Avaliação de pontos de contaminação por Salmonella sp. e coliformes totais durante o preparo de dietas para suínos

Pellegrini, Débora da Cruz Payão January 2012 (has links)
A presença de Salmonella é uma das mais importantes barreiras sanitárias à exportação de alimentos. A ração contaminada representa potencial fonte de introdução de Salmonella nos rebanhos suínos, além do risco indireto de infecção ao consumidor. Um estudo transversal conduzido em quatro fábricas de ração teve como objetivos avaliar a frequência de isolamento de Salmonella e coliformes totais nestas unidades, verificar a presença desses agentes nas diversas etapas do processo de produção, correlacionar grupos clonais de Salmonella sp. obtidos pela análise de macrorestrição associada à eletroforese em campo pulsado (PFGE), além de avaliar a concordância entre o escore obtido na aplicação de roteiro de inspeção da Instrução Normativa (IN) 4 do Ministério da Agricultura e Abastecimento e os níveis de coliformes totais encontrados. De 1.269 amostras analisadas, sessenta e três (4,96%) apresentaram Salmonella sp. e 38,53% (n=489) apresentaram presença de enterobactérias. As freqüências de contaminação por Salmonella nas quatro fábricas avaliadas (A, B, C e D) foram, respectivamente, 3,5% (n=11/317), 1,7% (n=5/289), 7,1% (n=23/308) e 7% (n=25/355). Já para coliformes totais foram, respectivamente, 40,7% (129/317), 30,1% (87/289), 52,6% (162/308) e 31,3% (111/355). Nas fábricas A e D, Salmonella foi detectada em amostras de produto final. Estirpes apresentando genótipos semelhantes foram identificadas nos sorovares Orion, Montevideo, Worthington e Agona. Foi possível verificar que o sorovar Montevideo obteve o maior número de grupos clonais, apresentando pulsotipos distribuídos entre ingredientes, poeira, equipamentos e ração. O isolamento de Salmonella foi significativamente mais frequente (p =0,002) em amostras com a presença (36/489; 7,36%) do que com ausência de coliformes totais (27/780; 3,46%). As contagens logarítmicas médias encontradas de coliformes totais, considerando todas as amostras analisadas por fábrica, foram: A: 0,97 (IC 95%: 0,81-1,13); B: 0,78 (IC 95%: 0,61-0,94); C: 1,32 (IC 95%: 1,16-1,49) e D: 0,91 (IC 95%: 0,75-1,06). Constatou-se elevada variabilidade no número de coliformes totais em todos os pontos amostrados nas quatro fábricas, e não houve diferenças significativas entre os pontos amostrados e entre as fábricas (p=0,174). A regressão logística tendo como variável resposta a presença de coliformes totais apontou maiores razão de chance (OR) de isolamento no transportador (OR=3,67; IC 95%: 2,28-5,89), dosagem (OR=9,51, IC 95%: 4,43-20,41), moagem (OR=7,1; IC 95%: 3,27-15,40), mistura (OR=4,08; IC 95%: 2,04-8,17), poeira (OR=3,50; IC 95%:2,10-5,84), resíduos (OR=6,22; IC 95%: 3,88-9,95) e fábrica C (OR=2,43; IC 95%: 1,68-3,53). Da mesma forma, o transportador (OR= 4,43; IC95%: 2,43-8,09) foi o local com maior probabilidade de isolamento de Salmonella, seguidos da poeira coletada nas dependências da fábrica (OR=2,88; IC95%: 1,41-5,88). Comparadas à fábrica B, as unidades C e D apresentaram, respectivamente, 2,74 e 2,83 mais chances de isolamento de Salmonella. Ao analisar os 128 itens necessários no Roteiro de Inspeção da IN4, a fábrica B obteve o menor número de não conformidades. Nas demais fábricas, as maiores inconformidades foram encontradas quanto à estrutura da área interna e externa das fábricas. As fábricas A e D foram as que apresentaram o maior número de itens não conformes relacionados à limpeza e higienização de equipamentos. Entre os 29 itens imprescindíveis na Avaliação de Estabelecimento e Procedimentos Operacionais Padrão, oito não foram cumpridos em pelo menos uma das fábricas. A fábrica B apresentou todos os itens em conformidade, ao passo que as fábricas A e D não cumpriram os oito itens. A fábrica C apresentou três itens não conformes, relacionados à limpeza de piso e parede, recepção e armazenamento de matérias-primas. Não houve concordância entre os escores obtidos no roteiro de avaliação e a média de coliformes totais encontrada nas fábricas, demonstrando que apenas a adequação à legislação pode não garantir a inocuidade do alimento produzido. A partir disso, conclui-se que é necessário implantar programas de monitoramento e controle microbiológico ao longo da linha de produção, independente da situação da fábrica em relação à legislação vigente. A elaboração e produção de equipamentos de fácil limpeza e com mínimo acúmulo de poeira e resíduos deve ser incluída nos programas de controle de Salmonella concomitante às demais medidas de controle preconizadas. / The presence of Salmonella is one of the most important sanitary barriers to food exports. The contaminated feed is a potential source of introduction of Salmonella in pig herds, and may also represent a risk to the consumer. A cross-sectional study conducted in four feed mills was carried out to evaluate the frequency of isolation of enterobacteria and Salmonella at various stages of feed production, to identify clonal groups of Salmonella sp. Obtained by macrorestriction analysis associated with pulsed field gel electrophoresis (PFGE), and to verify the association between the score obtained by feed mills after the application of the checklist of the Normative 4 (IN4) of the Ministry of Agriculture and Food Supply and the mean of total coliforms found in the unit. Among 1,269 samples analysed, sixty-three (4.96%) showed the presence of Salmonella. The four feeds mills evaluated (A, B, C and D) presented, respectively, 3,5% (n=11/317), 1.7% (n=5/289), 7,1% (n=23/308), and 7% (n=25/355) of positive samples. Total coliforms were isolated from 40.7% (129/317), 30.1% (87/289), 52.6% (162/308) e 31.3% (111/355) samples taken at unit A, B, C and D, respectively. In the units A and D, Salmonella was detected in samples of feed. Strains showing similar genotypes have been identified as Serovar Orion, Montevideo, Worthington and Agona. Serovar Montevideo presented the highest number of clonal groups, with common pulsotypes distributed among ingredients, dust, equipment and feed. The isolation of Salmonella was significantly higher (p=0,002) in samples with the presence of total coliforms (36/489; 7.36%) than in the negative ones (27/780; 3.46%). The mean logarithmic counts of total coliforms considering all samples were determined for each plant: A: 0.97 (95% CI: 0.81 to 1.13), B: 0.78 (95% CI: 0.61 to 0.94), C: 1.32 (95% CI: 1.16 to 1.49) and D: 0.91 (95% CI: 0.75 to 1.06). A high variability on the number of total coliforms in all the sampled points was found in all feed mills, and there was no statistical diference between the sampling sites and units (p=0.174). The logistic regression, with isolation of total coliforms as the response variable, showed a high odds ratio (OR) of isolation from conveyors (OR = 3.67, 95% CI: 2.28 to 5.89), dosing (OR = 9.51, 95% CI: 4.43 to 20.41), grinding (OR = 7.10, 95% CI = 3.27 to 15.40), mixing (OR = 4.08, 95 % CI: 2.04 to 8.17), dust (OR = 3.50, 95% CI: 2.10 to 5.84), crusts (OR = 6.22, 95% CI: 3.88 to 9.95) and unit C (OR = 2.43, 95% CI: 1.68 to 3.53). The conveyors (OR = 4.43, 95% CI: 2.43-8.09) were the most likely sites of isolation of Salmonella, followed by the dust collected on the premises of the plant (OR = 2.88, 95% CI: 1.41-5.88). Feed mills C and D showed, respectively, 2.74 and 2.83 higher odds for Salmonella isolation than feed mill B. The verification of the 128 items addressed on the Guidelines for Inspection of Normative 4 (IN 4) of the Brazilian Ministry of Agriculture and Food Supply pointed out that factory B had the lowest number of nonconformities. The other three feed mills, presented most faults related to the physical structure of the facilities. Feed mills A and D presented the largest number of nonconformities related to cleaning and sanitizing of equipment. Among the 29 mandatory items in IN4, eight were not met in at least one of the factories. Feed mill B presented all items accordingly, while plants A and D did not meet any of the eight items. Feed mill C had three non-compliant items related to the floor and wall cleaning, reception and storage of raw materials. There was no association between the score obtained on the inspection checklist and the level of total coliforms found in the sampled units, demonstrating that only the compliance to the legislation cannot guarantee the safety of feed produced. It was concluded that programs for monitoring and control microbial contamination throughout the production line are needed, regardless of the status of the plant in the relation to the current legislation.The design of equipment that allow easy cleaning and with minimal accumulation of dust and debris should be added to other measures in Salmonella control programs.

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