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O estado do Rio Grande do Sul é o maior produtor mundial de ágatas. No beneficiamento, as pedras são submetidas a processos de tingimento para agregar valor ao produto. A prática acarreta em um problema ambiental na região devido ao efluente líquido gerado no processo. Um dos processos de tingimento aplicados é com o corante Rodamina B, que proporciona uma coloração rosa avermelhada. Assim, o objetivo deste trabalho foi investigar o emprego da reação de Fenton combinada com a adsorção para o tratamento do efluente líquido contendo o corante orgânico Rodamina B gerado no tingimento de ágatas. O efluente industrial foi caracterizado e o estudo foi desenvolvido em três fases distintas: a primeira compreendeu o tratamento por meio da reação de Fenton; a segunda o emprego da adsorção como processo adicional após a reação de Fenton; e a terceira a integração de ambos os processos. O efluente continha uma concentração de 772 mg.L-1 de Rodamina B e 3% de etanol em sua composição, resultando em um fator de toxicidade (FT) de 526 para o organismo Daphnia similis. No tratamento pela Reação de Fenton, definiu-se como melhor dosagem 11,1 g.L-1 de sulfato ferroso e 20 mL.L-1 de peróxido de oxigênio (numa relação molar Fe2+/H2O2 de 1/7,5), o que permitiu a remoção total do álcool, uma redução média da absorbância em 554 nm de 99,9%, uma redução do COT de 93,3%, um incremento da tensão superficial de 58,9 para 64,4 mN.m-1 e o fator de toxicidade FT passou para 16 No estudo de adsorção, avaliaram-se os adsorventes carvão ativado, na forma pulverizada (CAP) e granulada (CAG), e cinza de casca de arroz (CCA). O carvão ativado pulverizado (CAP) se apresentou como a melhor opção para a remoção de cor residual após a reação de Fenton. A melhor condição para o descolorimento do efluente foi com o uso de uma concentração de CAP de 0,5 g.L-1 e um tempo de contato de 60 minutos. O pH do meio não apresentou influência dentro da faixa compreendida entre 6 e 9. A remoção da coloração residual visível foi completa. Contudo, o processo de adsorção não proporcionou mudanças substanciais no COT, na tensão superficial e do fator de toxicidade. A integração do processo Fenton com adsorção com CAP foi possível. A precipitação do Fe3+ gerado na Reação de Fenton em pH 8,0 possibilitou a coagulação das partículas de CAP, permitindo a clarificação do efluente. O ajuste do pH para 8,0 com Ca(OH)2 proporcionou uma redução dos íons sulfatos, da condutividade e a obtenção de um lodo mais denso do que com NaOH. O uso de um polímero floculante auxilia nesta operação, acelerando a etapa de separação sólido-líquido.A integração dos processos resultou em efluente sem coloração, com uma redução da carga orgânica acima de 90% e um FT igual a 4. Assim, conclui-se que a integração dos processos Fenton e adsorção agrega melhorias em aspectos operacionais e proporciona uma altaeficiência de tratamento. Os processos reúnem reações de oxidação, coagulação, air striping e adsorção que permitiram a remoção de poluentes. / The state of Rio Grande do Sul is the world's largest producer of agates. In the processing, the stones are submitted to dyeing processes to add value to the product. The practice causes an environmental problem in the region due to the wastewater generated in the process. One of the dyeing processes applied is with Rhodamine B, which provides a reddish-pink coloration. Thus, the objective of this work was to investigate the use of Fenton reaction combined with adsorption for the treatment of the wastewater containing the organic dye Rhodamine B generated in the agate processing. The industrial wastewater was characterized and the study was developed in three distinct phases: the first comprised the treatment through the Fenton reaction; the second, the use of adsorption as an additional process after the Fenton reaction; and the third, the integration of both processes. The wastewater contained a concentration of 772 mg L-1 of Rhodamine B and 3% of ethanol in its composition, resulting in a toxicity factor (FT) of 526 for the organism Daphnia similis. In the Fenton reaction treatment, 11.1 g L-1 of ferrous sulfate and 20 mL L-1 of oxygen peroxide (in a molar ratio Fe2+/H2O2 of 1/7.5) were defined as the best dosage, which allowed a total alcohol removal, an average absorbance reduction of 99.9% at 554 nm, a TOC reduction of 93.3%, an increase in surface tension from 58.9 to 64.4 mN m-1 and the FT toxicity factor decreased to 16. In the adsorption study, adsorbents evaluated were activated coal in the pulverized (CAP) and granulated (CAG) forms, and rice husk ash (CCA). The pulverized activated carbon (CAP) was presented as the best option for the removal of residual color after the Fenton reaction The best condition for discoloration of the wastewater was with the use of a CAP at a concentration of 0.5 g L-1 and a stirring time of 60 minutes. The pH of the solution had no influence within the range of 6 to 9. Removal of visible residual color was complete. However, the adsorption process did not provide substantial changes in TOC, surface tension and toxicity factor. Integration of the Fenton process with adsorption with CAP was possible. The Fe3+ precipitated in the Fenton reaction at pH 8.0 allowing coagulation of the CAP particles and the clarification of the effluent. Adjusting the pH to 8.0 with Ca(OH)2, instead of NaOH, provided a reduction in the concentration of sulfate ions, a decrease in the conductivity and a thicker slurry. The use of a flocculants assists this operation, accelerating the solid-liquid separation step. The integration of the processes resulted in an uncolored wastewater with an organic load reduction above 90% and a FT of 4. Thus, the integration of the Fenton and adsorption processes improves the operation and provides high treatment efficiency. The processes combine oxidation, coagulation, air striping and adsorption mechanisms that allowed the removal of pollutants.

Orientador: Rubens de Figueiredo Camargo / Resumo: Este trabalho apresenta uma investigação matemática e numérica da hepatite B por meio de modelos de ordem não inteira. Conceitos acerca da teoria do cálculo fracionário e de estabilidade para sistemas de ordens arbitrárias são abordados. Como aplicação, dois modelos formulados por meio de equações diferenciais fracionárias são introduzidos. O primeiro modelo é formulado sem parâmetros que indiquem a presença de terapia contra a doença, enquanto o segundo modelo considera a ação antiviral. A razão de reprodução básica e a análise de estabilidade são consideradas nos dois casos. Além disso, com intuito de analisar o comportamento das soluções para ambos os modelos, um estudo sobre o método de diferenças finitas não clássico é mostrado, bem como simulações numéricas são apresentadas. Os resultados numéricos mostram que as soluções convergem para o ponto de equilíbrio, conforme predito na análise de estabilidade. Para o modelo om terapia, visando encontrar a curva que ajusta os dados de pacientes, alguns parâmetros, incluindo a ordem da derivada fracionária, são estimados. Resultados da estimação mostram que a curva que se ajusta melhor aos dados reais possui ordem não inteira. / Abstract: This work presents a mathematical and numerical investigation of hepatitis B using non-integer order models. Concepts about fractional calculus and stability theory to arbitrary orders systems are discussed. We apply fractional differential equations to two models, the first disregarding the use of drug therapy and the second considering drug therapy. The first model is formulated without parameter that indicate the drug therapy. The second one, consider the drug therapy. The basic reproductive number and the stability analysis are considered in both cases. Moreover, for analyzing the solutions of models, a study about the numerical method Nonstandard Finitte Diference Squemes is shown, as well as the numerical simulations are presented. The numerical results shows that the solutions converges to the equilibrium point, as predicted by stability analysis. In order to find the curve that fits the data, we estimated some parameters, including the order of the fractional derivative. Estimation results show that the curve that best fits the data has a non-integer order. / Doutor

Vertebrate immune systems are armed with the ability to generate highly specific immune responses capable of responding to nearly any foreign molecular threat. One of the major mediators of this response is immunoglobulins (Igs) produced by B lymphocytes. The specificity of individual Igs is created through a tightly orchestrated series of somatic DNA manipulations at Ig encoding loci resulting in functional gene rearrangements and nucleotide substitutions. These events serve to create a pool of naive B cells expressing Igs with distinct specificities, capable of expansion in response to antigen specific selection. Affinity of Ig towards antigen is enhanced through nucleotide substitutions introduced at the antigen binding variable region gene segments through the enzyme activation induced cytidine deaminase (AID) during the process of somatic hypermutation (SHM). AID also generates point mutations within noncoding DNA segments of the Ig heavy chain locus that are processed into double strand breaks leading to constant region isotype switching during class switch recombination (CSR). The Ig diversification processes of SHM and CSR critically depend upon transcriptional activation of the relevant DNA segments. Transcription is thought to facilitate single strand DNA substrate recognition by AID during unwinding of the DNA duplex. The 3'-5' exoribonuclease RNA exosome serves as a transcription dependent cofactor of AID. RNA exosome is comprised of multiple structurally integral core subunits and associated nuclease subunits. In this work, RNA exosome core subunit Exosc3 and nuclease Exosc10 have been targeted for conditional mutagenesis and loss of function analysis in mouse cells. RNA exosome deficient B cells were significantly impaired in AID dependent SHM and CSR Ig diversification processes. Transcriptome analyses revealed a striking accumulation of promoter proximal antisense divergent noncoding transcripts (xTSS-RNA) at a subset of genes upon loss of RNA exosome function. xTSS-RNAs mark regions of chromatin containing RNA exosome activity. Multiple known AID target sites including IgH and Myc were observed to express xTSS-RNA. Furthermore, genomic sites of recurrent AID dependent chromosomal translocations were enriched for xTSS-RNA. In addition to promoter proximal xTSS-RNA, cryptic intragenic antisense noncoding transcripts were found to accumulate at many genomic loci. In fact, multiple translocation hotspots precisely overlap regions of RNA exosome sensitive antisense transcription. AID targeted divergently transcribed promoters containing RNA exosome substrates possessed greater amounts of RNA:DNA hybrids, indicative of frequent transcriptional arrest. Lastly, RNA exosome deficient transcriptomes have revealed a substantial number of novel long intergenic noncoding RNAs and enhancer RNAs, indicating a hidden layer of cellular transcriptional activity. A model of AID targeting utilizing transcriptional arrest is becoming increasingly apparent. Transcribed chromatin prone to undergo transcriptional arrest, such as Ig loci or xTSS-RNA expressing regions, frequently undergoes premature transcription termination coupled to RNA exosome mediated degradation of the nascent transcript. This process results in the creation of AID substrates and serves to stabilize its association with chromatin through multiple interactions involving RNA exosome and transcription complex subunits.

The NF-κB transcription factor is expressed in the majority of mammalian cells and regulates a large number of genes with important functions in a variety of cellular processes including cell growth, division, apoptosis and inflammatory responses. Perturbation of NF-κB response has been implicated in a variety of diseases such as asthma and inflammatory bowel disease, in addition to various forms of cancer. Through experiments at the single cell level it has been shown that NF-κB displays complex temporal activation, notably including nucleo-cytoplasmic oscillations. It has been observed that these oscillations occur in a heterogeneous manner; as such they are masked when measured at the population level. In contrast, pulsed TNFα treatment at 100 min intervals produces regular and synchronous nuclear peaks of NF-κB. Such pulsatile stimulation may reflect more accurately physiological conditions. The work in this project uses a Systems Biology approach consisting of bioinformatic, mathematical, and experimental methodologies to investigate how NF-κB can regulate such a diverse set of gene responses. Previously published studies have proposed that target gene expression levels following NF-κB activation (continuous TNFα) can be explained by a combination of key parameters, including transcript degradation rate, transcript structure, and transcription initiation rate. Initial work in this project highlighted that these explanatory factors are not sufficient to describe the observed temporal order of gene transcription. The roles of miRNAs and NF-κB subunit phosphorylation in regulation were additionally explored. A large set of genes was identified that are activated more strongly by pulsed TNFα than by continuous TNFα treatment. This suggests a new unreported mechanism of gene regulation, the possible causes of which are examined in this thesis. The gene list was refined by altering pulse frequency, which revealed an enrichment of NF-κB targets correlated with the regularity of these pulses. Temperature shift and anti-inflammatory drug treatment (Diclofenac) were shown to have a profound effect on NF-κB oscillation frequency. These perturbations provide an alternative method to study the effects of NF-κB oscillation frequency on specific target genes, independent of a pulse regime. Integration and analysis of these datasets suggested that a core, frequency-encoded set of genes regulated by NF-κB might exist. It is proposed that such genes may respond optimally to specific frequencies of NF-κB activation, implying a potential frequency threshold. The presence of such genes may explain the need for the complex systems that control NF-κB timing. It was noted that there was an enrichment of genes encoding transcription factors within the frequency encoding set, in addition to proteins which are known to be involved in the control of inflammation.

The NF-κB transcription factor p65/RelA controls hundreds of genes involved in inflammation, immunity, cell proliferation and survival. Cells treated with the inflammatory cytokine TNF-α show repeated nuclear-cytoplasmic translocations of p65 maintained by multiple negative feedback loops. Application of pulses of TNF-α at various set intervals can entrain the translocation frequency and cause different patterns of NF-κB-dependent gene transcription. Translocation frequency can also be altered by biological and environmental factors such as temperature and diclofenac treatment. These observations have led to the hypothesis that the dynamics of NF-κB play a role in the transcriptional responses dependent on particular cellular states. NF-κB can physically interact with members of other molecular networks including glucocorticoid signalling, the circadian clock and the cell cycle. In a previous study, two tumour cell lines showed differential p65 dynamics when treated with TNF-α at different cell cycle stages which concomitantly also altered cell cycle length. Evidence suggested that physical interactions between p65 and the cell cycle regulators E2F1 and E2F4 could, at least in part, be responsible for these effects. This thesis describes studies designed to investigate if similar responses exist in more normal cells. Although transcript levels of NF-κB target genes were suppressed in MEF cells treated with TNF-α during S phase relative to G1/S, NF-κB translocations appeared unaffected. Knowledge of the interactions with other molecular networks is central to understanding the context-dependent role of NF-κB, and the complexity of these dynamic interactions requires a Systems Biology approach. Within this study, a model of the interaction between NF-κB and the cell cycle was tested for its ability to recapitulate biological data from HeLa cells. Also, the effect of cell cycle timing of TNF-α treatment on NF-κB dynamics in HeLa cells was examined using ImageStream flow cytometry. It is suggested that a Systems Biology approach could be used to extend a study, initial results of which are presented here, of the interaction between NF-κB and glucocorticoid signalling. Understanding the interactions between NF-κB signalling and other networks should have clinical benefits, for example for cancer treatment dependent on circadian timing.

A measurement of the primordial B-mode polarisation of the Cosmic Microwave Background would provide direct evidence of inflation in the early universe. The extremely weak nature of the B-mode signal necessitates an instrument with a high sensitivity and precise control over systematic effects. Multi-mode antenna feed horns offer higher sensitivity than their single-mode counterparts, however their behaviour is much more complex. The Short Wavelength Instrument for the Polarisation Explorer (SWIPE) onboard the Large Scale Polarisation Explorer (LSPE) is one instrument planning to implement multi-mode feed horns. SWIPE will attempt to detect the primordial B-mode at large angular scales, measuring the sky in three bands at 140, 220 and 240 GHz. A single on-axis High-Density PolyEthylene (HDPE) lens and polarisation-splitting wire grid combine to focus the radiation from the sky onto two focal planes of multi-mode horns feeding bolometric detectors. A large diameter rotating metal-mesh half-wave plate allows both polarisations to be measured by the same pixel, therefore bypassing many detector systematics. Simulations are performed to predict the sky beam for two key pixels: closest to and furthest from the centre of the focal plane. For the 140 GHz channel the cross-polarisation is predicted, and the optimum location at which to place the telescope’s focus behind the horn aperture to maximise gain and optimise beam shape is investigated. A measurement of the multi-mode horn is performed using a room-temperature bolometer. An investigation is also conducted to assess to what extent the same measurements can be performed using a coherent measurement system such as a vector network analyser. A working coherent measurement technique is devised, however it is limited to horns carrying only the first 3 modes.

There is a discrepancy between the life expectancy of men and women of approximately two and a half years (Taylor Nelson Sofres 2014). This suggests that women are likely to spend a period of time in the latter years of their life living alone. It is anticipated that this will lead to a unique experience of later life for women, which to date has received little attention. This study is concerned with exploring the experience of living alone for 11 women aged 70-80 years from the South East of England. A particular emphasis is placed upon the experience of being an older woman, the activities that they engage in when they are at home alone, and the environment of home as a place for occupational engagement. Influenced by interpretive phenomenology and feminist principles, this study focuses on capturing the lived experiences of the 11 women in their own images and words. To achieve this, the methods of unstructured interviews and photo-elicitation are used. The women in this study describe a predominantly positive experience of living alone in later life. They value being busy, engage in a range of meaningful activities, and maintain their independence in everyday life. They provide compelling evidence that later life is a time for self-growth and development. This appears to link to the decline in the gender related roles and occupations which are expected of them in later life. This indicates that it is essential to provide bespoke support to older women that focuses on prevention of future decline but in a way that values their ongoing abilities.

The aim of this study was to uncover and illuminate aspects of spirituality, which may be present in the work of primary school teachers. Four themes emerged out the analysis and were coded using the methodology consistent with an Interpretative Phenomenological Analysis (IPA). The themes were: ● Spirituality as an aspect of identity formation and understanding. ● Relationships as central to understanding and formation. ● Teaching and learning as a shared encounter through mentoring. ● Spirituality as a contextual resource. IPA was chosen as a methodology as it places the participant as central to and expert in their lived experience whilst acknowledging the ways in which the researcher impacts on the interpretative process. Drawing on phenomenology whilst adopting a systematic process of analysis, the material uncovered ways in which spirituality can be used a resource in the professional encounter. The implications for this study points towards a new definition of spirituality that encompasses ‘moments of profundity and connection with other that leads to change’. This is particularly important in relation to the teachers in this study and could be of value to others in the education profession. Seeing one’s spirituality as a source of wisdom and as a contextual resource has allowed the participants to make connections with their colleagues and pupils that draw heavily on their spirituality in order to make sense of and bring change to situations and relationships. These instances are profound in nature for each individual but has brought about change in the situation, relationship or way of teaching and relating to one’s environment. As such the definition of spirituality in this study both encompasses established understanding of what it means to be spiritual but places this in the educational environment and profession. It is hoped that the findings of this study lead to an awareness of the way in which one’s spirituality can be drawn upon as a positive agential resource will be acknowledged in teacher education programmes and school-based teaching.

by Zhong Sheng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 186-203). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.