As determinações de alumínio são de grande interesse devido à sua toxicidade e sua ampla distribuição no meio ambiente. Além disso as determinações deste elemento por métodos analíticos convencionais apresentam dificuldades devido aos problemas da contaminação da amostra. O método de análise por ativação com nêutrons (NAA) para determinação de Al possui vantagens de rapidez na análise e de alta sensibilidade. Entretanto, neste método ocorrem os problemas de reações nucleares de interferência de P e Si. O Al na NAA é determinado pela medida do 28Al formado na reação 27Al (n, γ) 28Al, o mesmo radioisótopo formado nas reações nucleares 31P (n, α) 28Al e 28Si (n, p) 28Al. O objetivo deste estudo foi determinar Al pela NAA em amostras ambientais, fazendo a correção das interferências usando fatores de correção e dispondo das concentrações de P e de Si das amostras. Neste estudo foram analisados os materiais de referência certificados (MRCs) e amostras de biomonitores (cascas de árvore e líquen). O procedimento experimental consistiu na irradiação curta de uma alíquota de amostra no reator IEA-R1 juntamente com o padrão de Al, seguida de espectrometria de raios gama. O P foi determinado pela medida da radiação beta do 32P usando um contador Geiger-Müller. O Si foi determinado por meio da irradiação com nêutrons epitérmicos e medida do 29Al formado na reação 29Si (n,p) 29Al. Os resultados da determinação de Al, P e Si nos MRCs apresentaram uma boa precisão e exatidão com |Z-score| ≤ 2. As concentrações de Al obtido nos biomonitores variaram de 253 a 15783 μg g-1 e no caso da determinação de P e Si as concentrações destes elementos variaram de 283 a 1946 μg g-1 e de 0,11 a 7,8 %, respectivamente. Nos biomonitores analisados, as taxas de contribuição de interferência de P e de Si na determinação de Al foram da ordem de 2,0 % e esta contribuição depende das relações entre as concentrações dos interferentes e a do Al na amostra. Os limites de detecção de Al na análise dos biomonitores foram inferiores às suas concentrações demonstrando que procedimento de NAA proposto pode ser aplicado na determinação de Al neste tipo de matriz. / Aluminum determinations are of great interest since this element is toxic to humans and it is widely distributed in the environment. Besides, the determinations of this element by conventional analytical methods present difficulties due to sample contamination during the analyses. Neutron activation analysis (NAA) for Al determination presents advantages of fast analyses and of high sensitivity. However, NAA of Al does present problems of P and Si nuclear reaction interferences. Aluminum is determined by measuring 28Al, formed in the reaction 27Al (n, γ) 28Al, the same radioisotope formed in reactions 31P (n, α) 28Al and 28Si (n, p) 28Al. The purpose of this study was to determine Al in environmental samples by NAA correcting these interferences using correction factors, and determining P and Si concentrations in the samples. In this study, certified reference materials and biomonitor samples (tree barks and lichen) were analyzed. Experimental procedure consisted of irradiating an aliquot of the sample at the IEA-R1 nuclear research reactor together with Al standard, followed by gamma ray spectrometry. Phosphorus was determined by measuring beta radiation of 32P using a Geiger-Müller counter. Silicon was determined by epithermal neutron activation analysis and measuring 29Al formed in the reaction 29Si (n, p)29Al. Results obtained in the determination of Al, P and Si in the certified reference materials showed good precision and accuracy with |Z-score| ≤ 2. Aluminum results in the biomonitor samples varied from to 253 to 15783 μg g-1. In the case of P its concentrations varied from 283 to 1946 μg g-1. Silicon determinations in biomonitors varied from 0.11 to 7.8 %. The interference contribution rates in the analyses of the biomonitor samples were of the order of 2.0 % and this contribution depends on the relation between concentrations of interfering elements and of Al in the sample. Detection limit values of Al in the biomonitor analyses were lower than their concentrations in the samples demonstrating that the proposed procedure of NAA can be applied in the Al determination in this kind of matrix.

Melhorar o conhecimento sobre o minério lavrado é um desafio enfrentado diariamente pelas empresas de mineração. O presente trabalho trata de um estudo realizado na mina de apatita, localizada na cidade de Cajati, interior do Estado de São Paulo, de propriedade da Bunge Fertilizantes S/A, onde são abordados temas relacionados ao planejamento de lavra de curto prazo, visando o aprimoramento dos procedimentos de coleta de amostras de pó-de-perfuratriz, que são sistematicamente coletadas com o objetivo de controle de qualidade da lavra, contribuindo para uma efetiva melhoria na gestão do planejamento de lavra e na tomada de decisões. Os resultados obtidos mostram que, da forma como as amostras são coletadas, ocorre um enriquecimento do teor de P2O5, podendo levar a tomada de decisões erradas por parte da operação da mina. / Improve knowledge of the ore mined is a challenge faced daily by mining companies. This paper is a study in apatite mine, located in the city of Cajati, within São Paulo,propriety of Bunge Fertilizantes S/A, where are treated issues related to short term planning of the mine to improve procedures for collecting dust samples drilling, which are systematically collected for the purpose of quality control of mining, contributing to an effective improvement in the management of planning of mining and decision making. The results show that the way the sampling is done, there is an enrichment of content in P2O5, which can lead to making wrong decisions by the operation of the mine.

Este estudo de caráter qualitativo e quantitativo, tipo exploratório-descritivo, trata da caracterização do trabalho de enfermagem em laboratórios de análises clínicas. O objetivo geral visa identificar os aspectos da atuação da enfermagem nos laboratórios de análises clínicas, que permitam caracterizar o processo de trabalho da enfermagem. Os objetivos específicos buscaram identificar os trabalhadores da saúde que atuam na coleta de exames; reconhecer as atividades desempenhadas pelos diferentes agentes da enfermagem e conhecer sua inserção na estrutura organizacional. O referencial teórico adotado pautou-se nos estudos do processo de trabalho e de recursos humanos em saúde e em enfermagem. Para a coleta de dados utilizou-se um questionário e a amostra foi composta por 45 instituições. A análise dos resultados revelou que, quanto à caracterização dos laboratórios, 15,6% não realizam treinamento em serviço e 60% fazem-no de modo isolado, não continuado; o enfermeiro é o profissional que assume majoritariamente a responsabilidade por essa ação. Quanto aos recursos humanos, 77,8% são auxiliares de enfermagem, 13% enfermeiros e 9,1% técnicos de enfermagem. Evidencia-se a divisão social e técnica do trabalho, no qual os auxiliares executam o cuidado direto, o enfermeiro gerencia o processo e os técnicos desempenham ambas ações, sem diferenças relevantes entre as atividades dos auxiliares e técnicos de enfermagem. Além disso, há outros profissionais que compartilham das mesmas atividades realizadas pela enfermagem e esta se encontra, em grande parte, subordinada a outras áreas de atuação, com escassa autonomia na estrutura organizacional. / This qualitative and quantitative study, an exploratory-descriptive study, examines the characteristics regarding the work performed by nursing professionals in clinical laboratories. The general goal aims to identify roles played by nursing professionals in clinical laboratories that allow us to characterize the nursing work process. The specific goals seek to identify health workers that are responsible for collecting samples, to distinguish the activities played by different nursing professionals and to learn how they are inserted in the organizational structure. The theoretical reference adopted is based on studies regarding work procedures and human resources in health and nursing. A questionnaire was used to collect data and the sample comprised 45 institutions. Regarding the clinical laboratories, result analysis revealed that 15.6% of them do not offer in-service training and 60% do not do it on a continuous manner; nurses basically take on the responsibility for training other nursing professionals. Regarding human resources, 77.8% are nursing assistants, 13% are nurses, and 9.1% are practical nurses. There is evidence of a social and technical division of the workload: nursing assistants provide direct care, nurses manage the processes, and practical nurses perform both activities. No relevant differences were observed between the activities played by nursing assistants from those played by practical nurses. Furthermore, there are other professionals that share the same activities played by those nursing professionals. In most cases, nursing professionals are subordinated to other areas and have little autonomy in the organizational structure.

Este trabalho teve como objetivo avaliar os efeitos de diferentes doses de radiação gama no crescimento de Alternaria alternata e na produção das toxinas Alternariol (AOH) e Alternariol Monometil Éter (AME), em amostras de cereais. Como resultado, nos grãos de arroz e nas sementes girassol observou-se diminuição do número de UFC/g, proporcionalmente à dose de radiação utilizada. Nos grãos de trigo e milho, o aumento da dose, resultou-lhes aumento das UFC/g. A análise micotoxicológica revelou, nos grãos de trigo e sementes de girassol, menor produção de AOH. Já nos grãos de arroz e milho, o grupo irradiado com 5 kGy, foi o que mais produziu AOH. Resultado semelhante foi constatado em relação à produção de AME. A microscopia eletrônica de varredura possibilitou a visualização de alterações estruturais provocadas pelas diferentes doses de radiação gama. A análise dos padrões das toxinas AOH e AME irradiados, não sofreu alterações. / The present study aimed to evaluate the effects of different gamma irradiation doses on the growth of Alternaria alternata and on production of mycotoxins Alternariol (AOH) and Alternariol Monomethyl Ether (AME) in cereal samples. The results showed a significant reduction in the number of CFU/g in rice grains and sunflower seeds, which were proportional to radiation dose used. However, in corn and wheat grains was observed an increase in the number of CFU/g with the increase of gamma irradiation. The radiation doses used resulted in a reduction of AOH levels. In rice and corn grains, the production of AOH was highest in the group irradiated with 5 kGy. Similar result was obtained with relation to AME. Scanning electron microscopy made it possible to visualize structural alterations on A. alternata induced by the different g-radiation doses used. Analysis of irradiated AOH and AME toxins standards didn´t show any alteration comparing to the control group.

A interpretação dos achados laboratoriais no estabelecimento da causa mortis consiste na integração dos conhecimentos sobre a toxicocinética e toxicodinâmica do agente, conhecimentos de sua redistribuição post mortem (RPM) e achados necroscópicos que possibilitem o nexo causal entre o toxicante e o efeito letal. Neste sentido, é importante considerar que somente as concentrações de cocaína (COC) e seus metabólitos podem não ser determinantes na interpretação da causa de morte, podendo ser útil o cotejamento com outros parâmetros, como os níveis de neurotrasmissores que representem o mecanismo de ação do fármaco. Assim, este trabalho teve por objetivo investigar a RPM da COC e seu metabólito benzoilecgonina (BE) em três segmentos do tecido encefálico (TE), no humor vítreo (HV) e sangue (SG), bem como determinar as concentrações de catecolaminas e indolaminas no encéfalo para avaliar a aplicação da neuroquímica post mortem (NPM) na toxicologia forense. No estudo de RPM foram quantificados os níveis de COC e BE em três segmentos do TE (córtex frontal, núcleos da base e cerebelo), no HV e no SG através de método por cromatografia líquida de alta eficiência (HPLC) acoplada ao detector de arranjo de diodos. Os estudos de neuroquímica foram realizados empregando-se HPLC acoplada ao detector eletroquímico. Os resultados indicaram que as concentrações médias de COC foram maiores no TE, seguido por SG e HV (3,09, 2,92 e 1,71 µg/mL, respectivamente), enquanto para BE foram maiores em SG, seguido por HV e TE (6,12, 1,39 e 0,87 µg/mL, respectivamente). As concentrações de COC se apresentaram distribuídas uniformemente nos três segmentos de TE e apresentaram alta correlação com o HV. Adicionalmente, a média de concentrações de dopamina total foi maior no grupo de indivíduos com amostras positivas para COC, sendo verificado diferença significativa entre este grupo e o de indivíduos com amostras negativas para o fármaco de interesse. Os resultados demostraram que o estudo de RPM e da NPM constituem ferramentas aplicáveis na interpretação da causa e maneira de morte. / In case of intoxication, the interpretation of analytical results to assess the cause and process of death requires knowledge about toxicokinetics, toxicodynamic, postmortem redistribution, and autopsy elements. Cocaine-related deaths occur mainly after prolonged drugs use and the presence of cocaine (COC) in fluids or tissues does not prove that death was due to COC consumption, and the interpretation of postmortem concentrations is even more complicated than attempts at making such correlations in the living. The objectives of this study were to investigate the post mortem redistribution (PMR) of COC and its metabolite benzoylecgonine (BE) in three segments of brain (frontal cortex, base nucleous, and cerebellum), vitreous humor, and blood. In additional, catecholamines and indolamines were quantified in brain in order to evaluate the usefulness of post mortem neurochemistry (PMN) in forensic toxicology. In PMR studies were quantified the COC and BE levels in three brain (BR) segments, in vitreous humor (VH), and blood (BL) by High Performance Liquid Chromatography (HPLC) with diode array detection, and for neurochemistry studies the neurotransmitters were quantified by HPLC with electrochemical detection. A homogenous distribution of COC and BE within frontal cortex, base nucleous, and cerebellum was found. The COC media concentrations were 3.09, 2.92 e 1.71µg/mL in BR, BL and VH, respectively, and the BE media concentrations were 6.12, 1.39 e 0.87 µg/mL in BL, VH, and BR, respectively. The COC concentrations in VH show high correlation with brain. The media total dopamine concentration was significant higher in COC positive group. These findings suggest that the studies of PMR and PMN by neurotransmitters levels may be useful to assess the cause and process of death.

Neste trabalho desenvolvemos um procedimento simples para a separação de nanoesferas ocas de carbono (do inglês Carbon Spherical Shells ou CSS) em diâmetros entre 400 e 500 nm utilizando centrifugação corroborado pelas análises realizadas na microscopia eletrônica de varredura e de transmissão. A análise de sua composição química, realizada através da técnica de fotoelétrons excitados por raios X, indicou que as CSS são constituídas de 79% de carbono e 21% de oxigênio em sua superfície, apresentando grupos funcionais carbonila e hidroxila. Plataformas sensoriais distintas foram obtidas formando filmes homogêneos das CSS sobre o eletrodo de carbonno vítreo GCE (do inglês glassy carbon electrode ou GCE). Como resultado dos experimentos eletroanalíticos, observou-se o aumento da sensitividade do eletrodo GCE/CSS de acordo com a diminuição do diâmetro (500 até 400 nm) das CSS. As plataformas sensoriais GCE/CSS com 400 nm de diâmetro apresentaram maior sensitividade (0.02 μA µmol L-1) com um limite detecção de 0.2 μmol L-1. Os eletrodos GCE/CSS foram estáveis, apresentando pequena interferência de espécies concomitantes presentes na amostra e seu desempenho na quantificação de paracetamol em suor mostrou-se estatisticamente equivalente ao método padrão baseado em cromatografia líquida. / We applied a simple strategy, based upon centrifugation, to separate carbon spherical shells (CSS), in sizes varying from 400 to 500 nm, which is shown by the micrographs obtained in the Scanning and Transmission Electron microscopy analysis. In their surface, carbonyl and hydroxyl groups were present, constituting a composition of 21% of oxygen and 79% of carbon. The CSS were casted on a glassy carbon electrode\'s (GCE) surface, forming a thin film, and the resulting platform was used as a sensor. A trend was observed in the results obtained by the electroanalytical experiments: as the size of the CSS were reduced, the sensibility of the GCE/CSS platform towards paracetamol detection increased. The best attained result, namely the platform with the GCE and the 400 nm diameter CSS, have shown promising results, achieving sensitivity\'s value of 0.02 μA μmol-1 L. The proposed sensors were stable, displaying little interference from another species coexisting in the samples, and its performance towards paracetamol detection were statistically identical to the standard method for paracetamol detection based upon liquid chromatography.

Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in a number of common household and commercial products around the world. PBDEs enter the environment in a variety of ways, such as through emissions, leaching from end-of-life electronics in landfills, and incineration. While many countries have phased out the manufacturing of penta-, octa-, and deca-PBDEs or have banned the manufacture and use of these congeners altogether, these persistent organic pollutants (POPs) continue to be detected in humans and the environment. This study investigates spatial and temporal variations of selected PBDEs in the air of the Nandamojo watershed area in Costa Rica by comparing air concentrations of PBDEs in the dry winter vs. wet summer seasons and rural vs. urban areas and also investigates the impact of anthropogenic activities on air concentration of PBDEs. This study is significant to the field, because there are no baseline studies nor are there currently any monitoring programs to assess the environmental levels of PBDEs or other POPs for this region of the Guanacaste province. Baseline information is needed to track spatial and temporal trends as well as evaluate the effectiveness of control measures employed nationally and internationally. Samples obtained from passive air sampling devices were analyzed via GC/MS for a number of congeners. PBDE-47 and -99 were found to be the congeners present in greatest concentration in air samples from the Nandamojo watershed area. Air concentrations were estimated assuming an average sampler uptake rate of 3.5 m3/day and ranged as follows: ΣPBDE5 35.20-1549.25 pg/m3 over the entire study. The presence of PBDEs in remote and pristine environments indicates that PBDEs are now a global concern. This study suggests that the spatial and temporal distribution patterns observed are strongly related to anthropogenic activities and presence of a population similar to that observed in other studies. The presence of PBDEs has become a global issue and, as such, these results provide background information on air concentrations of PBDEs for use in a global-scale multimedia model. In order to monitor PBDEs globally, it is imperative to implement and/or expand surveillance programs internationally.

<p>Infrared absorption spectra can provide analytically useful information on a large variety of compounds, ranging from small ions to large biological molecules. In fact, all analytes that possess a dipole moment that changes during vibration are infrared-active. The infrared (IR) spectrum can be subdivided into far-, mid- and near- regions. The focus of attention in this thesis is the mid-IR region, in which the fundamental vibrations of most organic compounds are located, thus providing scope for positive structural identification. However, while such near-ubiquitous signals can be very useful for monitoring simple molecules in simple systems, they can be increasingly disadvantageous as the number of analytes and/or the complexity of the sample matrix increases. Thus, hyphenation to a separation system prior to detection is desirable. Paper I appended to this thesis presents (for the first time) the on-line hyphenation between Fourier transform infrared spectroscopy, FTIR, and capillary zone electrophoresis, CZE. CZE is a highly efficient separation technique that separates ionic analytes with respect to their charge-to-size ratio. It is most commonly performed in aqueous buffers in fused silica capillaries. Since these capillaries absorb virtually all infrared light an IR-transparent flow cell had to be developed. In further studies (Paper II) the applicability of CZE is expanded to include neutral analytes by the addition of micelles to the buffer, and micellar electrokinetic chromatography, MEKC, was successfully hyphenated to FTIR for the first time. Paper III describes an application of the on-line CZE-FTIR technique in which non-UV-absorbing analytes in a complex matrix were separated, identified and quantified in one run.</p><p>Measuring aqueous solutions in the mid-IR region is not straightforward since water absorbs intensely in this region, sometimes completely, leaving no transmitted, detectable light. For this reason, quantum cascade lasers are interesting. These lasers represent a new type of mid-IR semiconducting lasers with high output power due to their ingenious design. The laser action lies within one conduction band (intersubband) and can be tailored to emit light in the entire mid-IR region using the same semiconducting material. To investigate their potential to increase the optical path length in aqueous solutions, these lasers were used with an aqueous flow system (Paper IV), and the experience gained in these experiments enabled hyphenation of such lasers to a CZE system (Paper V).</p>

Graduation date: 2006 / This research addresses sample process variance estimation on continuous domains and for non-probability samples in particular. The motivation for the research is a scenario in which a program has collected non-probability samples for which there is interest in characterizing how much an extrapolation to the domain would vary given similarly arranged collections of observations. This research does not address the risk of bias and a key assumption is that the observations could represent the response on the domain of interest. This excludes any hot-spot monitoring programs. The research is presented as a collection of three manuscripts. The first (to be published in Environmetrics (2006)) reviews and compares model- and design-based approaches for sampling and estimation in the context of continuous domains and promotes a model-assisted sample-process variance estimator. The next two manuscripts are written to be companion papers. With the objective of quantifying uncertainty of an estimator based on a non-probability sample, the proposed approach is to first characterize a class of sets of locations that are similarly arranged to the collection of locations in the non-probability sample, and then to predict variability of an estimate over that class of sets using the covariance structure indicated by the non-probability sample (assuming the covariance structure is indicative of the covariance structure on the study region). The first of the companion papers discusses characterizing classes of similarly arranged sets with the specification of a metric density. Goodness-of-fit tests are demonstrated on several types of patterns (dispersed, random and clustered) and on a non-probability collection of locations surveyed by Oregon Department of Fish & Wildlife on the Alsea River basin in Oregon. The second paper addresses predicting the variability of an estimate over sets in a class of sets (using a Monte Carlo process on a simulated response with appropriate covariance structure).

Development and improvement of analytical techniques are vital in analytical chemistry research. This thesis describes the development and use of tailored surfaces for bioanalytical applications. In sample preparation, solid phase extraction is often used and the development of a protocol for extraction on a molecular imprinted polymer (MISPE) directly from plasma sample is presented. Molecular imprinted polymers (MIP) offer selective sorbents for the imprinted analyte. MISPE has mainly been used in organic phase but in this thesis the development of a protocol for direct extraction of the analyte form an aqueous phase is described. For analysis of complex samples a separation step is often needed. The growing interest in analysis of biological samples and analysis of the human proteome and potential biomarkers has increased the interest in developing new separation techniques. Capillary electrophoresis (CE) has evolved into an important technique for use in analysis of body fluids. In this thesis a novel polyamine coating named PolyE 323 tailored for minimizing the adsorption of basic proteins to the surface is introduced. A straightforward coating protocol, with four simple rinsing steps, was developed. The coating was highly reproducible and useable over a wide pH range. Successful protein separations on PolyE-323-coated capillaries coupled to electrospray ionization mass spectrometry (ESI-MS) were demonstrated. The coated capillaries were also used in studies of protein content of aqueous humor samples from cataract patients as a complement to capillary liquid chromatography. In the studies presented the protein content of aqueous humor samples from two clinical groups was compared. By using capillary liquid separation techniques coupled to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and MS/MS in combination with isobaric tags for relative and absolute quantitation (iTRAQ) the identity and relative concentrations of proteins in the samples were evaluated. Earlier studies of the proteins in these kinds of samples have mainly been done with techniques using immunological detection where the proteins of interest were chosen in advance. In this thesis it was shown that liquid-based separation techniques are a good complement and by using the mass spectrometry approach presented the protein content of the samples could be evaluated without bias.