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Introduction: Dysproteinemia is associated with kidney damage and treatment of underlying conditions is crucial to minimize kidney damage. The aim of this study was to describe and analyze the characteristics and outcome of the patients diagnosed with dysproteinemia-associated kidney disease with initial renal presentation. Methods: We performed a retrospective observational study of the patients admitted with initial dysproteinemia-associated kidney disease in the Department of Nephrology and Renal Transplantation at Centro Hospitalar Universitário Lisboa Norte in Lisbon over five years. Results: Thirty patients were diagnosed with dysproteinemia-associated kidney disease: twenty-six (86.7%) with multiple myeloma, one of these with concomitant amyloidosis; three (10.0%) with gammopathy of renal significance and one (3.0%) with Waldenström macroglobulinemia. Mean age was 71.5 (± 12.44) years and half patients were male. Anemia, hypercalcemia, hyperphosphatemia, and hypoalbuminemia was found in twenty-three (76.7%), ten (30.0%), fourteen (46.7%) and seventeen (56.7%) patients, respectively. Bence Jones proteinuria was found in twenty-one (70.0%) patients and thirteen (43.3%) patients presented with creatinine >6 mg/dL. Twelve (40.0%) patients were submitted to kidney biopsy and light chain cast nephropathy was the most common finding. Twenty-nine (96.7%) patients were treated with chemotherapy. Twenty-two (72.3%) patients required renal replacement therapy and six of these (27.3%) patients were submitted to high cut-off dialyzers. Four (13.3%) patients had full recovery of renal function, sixteen (53.3%) remained dialysis-dependent at hospital discharge. At one-year follow-up, eleven (36.7%) patients remained dialysis-dependent and six (20.0%) had died. Conclusion: Dysproteinemia-associated kidney disease can present heterogeneously, and diagnostic suspicion is crucial to start prompt directed therapy to improve kidney and overall outcomes. Renal replacement therapy requirement and dependence at discharge appear to be related to higher mortality in these patients. In the future, routine screening of dysproteinemia may be particularly relevant in older patients to prevent irreversible kidney damage.

Little is known of the response of Portuguese Dão wine appellation’s most common grapevine cultivars to the causal agents of esca and Petri diseases, despite the high incidence of both diseases in the region and the consequent economic losses. Phaeomoniella chlamydospora has been considered one of the major causal agents of these diseases in that region. The present study evaluated the responses of four of the most propagated Dão’s grapevine cultivars – Alfrocheiro, Aragonez, Jaen and Touriga Nacional – to infection by three different Portuguese isolates of P. chlamydospora. Field trials were conducted in 2012, 2013 and 2015. The cultivar Alfrocheiro was the most susceptible to P. chlamydospora while cv. Jaen was the least. Variation in parameters such as lesion length and pathogen recovery from infected spurs (within trial years) suggest relation of pathogenicity with weather data, particularly temperature. Differences in aggressiveness among isolates were also detected, with one, a non-native, being the most aggressive. These results provide valuable information for local winegrowers, identifying, for the first time, susceptibility differences among local cultivars to P. chlamydospora, and suggesting adjustments to recommended pruning strategies, specifically to leave long spurs and avoid late winter pruning, thus reducing grapevine trunk colonization by P. chlamydospora.

Vascular access (VA) dysfunction is an important cause of morbidity and mortality in the hemodialysis (HD) population. Regardless of the increasing prevalence of HD patients with complex VA, the definitions of VA failure (VAF) or end-stage VA failure (ES-VAF) are still being discussed and there is no current guideline that provides recommendation for solving the problem of complicated vascular access. The aim of this study was to review the management approach for resuming the continuity of RRT in patients with problematic vascular accesses, based on our center experience. In a retrospective analysis of 30 patients with VAF or ES-VAF over an 11-year period, twenty patients were transferred to peritoneal dialysis (PD), seven patients remained in HD after the placement of a non-standard site VA and three patients had a renal transplant (RT). In half of these patients, the initial therapeutic option eventually failed, leading to multiple reinterventions and RRT changes. Mean survival was 47 ± 32.7 months. Ten patients died, the majority within the first year of VAF diagnosis. The management of end-stage renal disease patients includes vessel preservation, the combination of RRTs to extend life expectancy and VA care to maintain long-term function. Our approach stratifies patients according to exhausted VA sites in order to plan for RT, transition to PD or alternative VA site management. This allows for better management of the VAF patient and highlights the need to individualize patient care.

Black rot on grapevine is a fungal disease caused by Phyllosticta ampelicida (syn. Guignardia bidwellii) affecting grape leaves as well as clusters. A novel black rot decision support system termed VitiMeteo Black rot was assembled based on existing sub-models and incorporated into the established VitiMeteo forecast and decision support platform. Based on local weather data and a 5-day weather forecast, VitiMeteo Black rot simulates the relative susceptibility of grape clusters, the occurrence and severity of infection events as well as the duration of incubation periods. Data sets obtained in extended international (14 case studies; eight monitoring locations; 11 cultivars; seven countries in Europe and North America) field monitoring campaigns in 2012 and 2013 were used to evaluate the model predictions of newly expressed symptoms on leaves. In the case of the Vitis vinifera cultivars, on average 26.3 disease assessments took place per season. On average, 9.9 predictions were classified as true positive, 8.0 as true negative, 5.2 as false positive and 3.2 as false negative. Model precision, sensitivity and accuracy were on average 64, 77 and 67 %. Potential reasons for false positive and false negative predictions are discussed. VitiMeteo Black rot is freely available for several locations in Germany, Luxembourg and Austria on the internet via the VitiMeteo platform and might be expanded to other regions in the future.

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2018 Submitted by Sofia Amador (sofiamador@fm.ul.pt) on 2020-03-24T10:58:09Z No. of bitstreams: 1 SofiaVJorge.pdf: 479392 bytes, checksum: 7a29e334d70c414719ddcb06d3946954 (MD5) Made available in DSpace on 2020-03-24T11:59:42Z (GMT). No. of bitstreams: 1 SofiaVJorge.pdf: 479392 bytes, checksum: 7a29e334d70c414719ddcb06d3946954 (MD5) Previous issue date: 2018

Chronic kidney disease (CKD) is associated to significant infection incidence and severity, the cause of death of, approximately, 20% of end-stage renal disease patients. Close to 80% of all infections in these patients can be related to organ or tissue other than vascular access, reflecting immune system dysfunction related to several mechanisms. Strongyloides stercoralis is an endemic nematode found especially in tropical and subtropical areas. The clinical manifestations of stercoralis infection vary according to the acuity of infection and the host response, from asymptomatic to the disseminated presentation, frequently lethal. Risk factors for severe presentations are related to immunosuppression states. The authors report a case of a patient with advanced CKD of unknown etiology, who developed an exuberant eczema, respiratory symptoms and severe hypereosinophilia. The etiological study revealed a disseminated form of Strongyloides stercoralis infection with myocardia involvement, diagnosed solely by serologic testing, despite microbiological tests to identify the infective agent. In this case, the patient has evolved favorably, with remission of symptoms and cardiac features, after adequate anti-helminthic treatment. The importance of parasitic colonization and its potential harm becomes clinically more relevant when patients become immunosuppressed, as in CKD progression or in the immunosuppressive therapy setting, such as solid organ transplant rejection therapy. A brief literature review related to strongyloidiasis and immunosuppression in the CKD setting is also presented

This article shares the experience of the making of a graphic diary as a support to illustrate a children's book, with students from the 5th and 6th grades of Colégio Pedro Arrupe, during the Semana do Mar (Sea's Week), a school week dedicated to project-based learning and group work. This graphic diary documents the process of illustration, its graphic regulations (concerning the cover and back-cover), the experimentation of several art supplies, the ideas along the way; this transforms the diary into a graphic research portfolio, highlighting the student's autonomy, self-criticism and reflection

Membranous nephropathy (MN) is the most common cause of nephrotic syndrome in Caucasian adults aged over 60 years old. Approximately two thirds of cases of membranous nephropathy (MN) in adults are primary (idiopathic), and the remaining are secondary forms which have been attributed to a variety of agents or conditions. Recent advances in pathophysiology and the availability of new laboratory diagnostic methods reinforce the importance of differentiating idiopathic from secondary MN, given the repercussions on therapy. We present the case of a 71-year-old Caucasian male referred to Nephrology due to nephrotic syndrome. He had a history of gastric adenocarcinoma and of parathyroid cancer, but was considered cured. Investigation excluded immunologic disease, dysproteinaemia, chronic infection and active malignancy. Kidney biopsy was performed and confirmed MN. Histological characterization of IgG subtypes was not available, nor was biopsy study for the reactivity for PLA2 receptor. The patient was started on conservative treatment, but, after a one-year follow-up, presented persistent nephrotic proteinuria (5g/day) and renal function decline (serum creatinine of 1.6mg/dL). Serological determination of phospholipase A2 receptor antibody was positive, but with borderline titer. Considering his history of malignancy as well as kidney function deterioration, Rituximab was prescribed. At one year of follow-up the patient has proteinuria of 500 mg/day, stable renal function (serum creatinine of 1.2 mg/dL) and negative serum anti-PLA2 receptor antibody. Despite the recent availability of serological determination of phospholipase A2 receptor antibody and histological characterization of IgG subtypes, in this case they did not allow us to safely distinguish between idiopathic and secondary MN. Therefore the past medical history played a significant part in the therapeutic option. Recent studies suggest that Rituximab has similar results to non-specific immunosuppression, promoting remission in patients with severe and persistent MN, with less adverse effects, and thus can be considered as first-line therapy

The increasing prevalence of end-stage chronic kidney disease associated with advances in treatment is expected to lead to improved survival rates of chronic haemodialysis patients in Portugal. Establishing and maintaining vascular access patency is becoming a challenging issue in these patients. We present a case report of a multiple vascular access failure patient to whom a novel vascular access device was implanted which allowed successful haemodialysis, despite the presence of central venous stenosis and/or occlusion. To our knowledge the present case report describes the first utilization of Hemodialysis Reliable Outflow (HeRO) Graft device in Portugal. We present the case as well as a brief description of the device and available literature. This case report also underlines the importance of adopting a multidisciplinary approach in order to overcome complex and life-threatening clinical challenges

Background: Understanding the aetiology and approach to management of chronic kidney disease presenting in the paediatric age range continues to represent a true challenge. With the improvement of paediatric care, the number of patients reaching adulthood has increased in recent decades, and it is well known that the transition period from paediatric to adult care is critical; it is associated with a high rate of dropout from care, making it imperative to have an organized system. Methods: Hospital Santa Maria has followed a transition model for the last 17 years in order to optimize medical care for patients with chronic kidney disease who reach adulthood before progressing to end-stage renal disease (ESRD). From 1998 to 2013, our unit has managed 151 such patients. We retrospectively analysed this population with regard to their demographic data, renal diagnosis, follow-up and outcomes. Results: The most prevalent pathologies were uropathies (61 patients), glomerulopathies (46 patients), tubulopathies (18) and cystic diseases (seven), with “other causes” found in 15 patients. Each group was char- acterized individually. The mean annual decrease of the glomerular filtration rate (GFR) was 2.4ml/ min/1.73m2/year. Fourteen patients developed end-stage renal disease, four were transferred to other hospitals and 18 dropped-out. Eighty-six per cent had finished high school, 60% were working, 32% were students and 8% were unemployed. Conclusion: The aetiology of renal disease presenting in paediatric age is singular. Our dropout rate and annual decrease of GFR are lower than in units with no transition model. The majority of patients choosing haemodialysis had a previous mature fistula. More studies are needed Introdução: A etiologia, abordagem e manejo da doença renal crónica com início em idade pediátrica constiui um verdadeiro desafio. Nas últimas décadas, com o desenvolvimento dos cuidados pediátricos, o número de doentes a transitar para a nefrologia de adultos tem vindo a aumentar. É do nosso conhecimento que o periodo de transição é uma fase crítica, caracterizada por uma elevada taxa de abandonos, tornando-se deste modo necessário contar com um sistema organizado. Métodos: O Hospital de Santa Maria adoptou um modelo de transição, em vigor nos últimos dezassete anos, de modo a optimizar os cuidados prestados aos doentes renais crónicos pediátricos que atingem a fase adulta sem ainda necessitarem de terapêutica de substituição da função renal. Entre 1998 e 2013, foram observados cento e cinquenta e um doentes na Consulta de Transição. Os autores analisaram retrospectivamente esta população no que respeita a demografia, doença renal, follow-up e outcome. Resultados: As patologias distribuiram-se por uropatias (61 doentes), glomerulopatias (46), tubulopatias (18), doenças quísticas (sete) e “outras causas” (15 doentes). Cada etiologia foi caracterizada individualmente. A diminuição média anual da taxa de filtração glomerular foi de 2,4 ml/min/1,70m2/ano. Catorze doentes desenvolveram necessidade de terapêutica de substituição da função renal, quatro foram transferidos para outros hospitais e dezoito abandonaram a consulta. Oitenta e seis por cento tinham completado o ensino secundário, 60% estavam empregados, 32% eram estudantes e 8% estavam desempregados. Conclusão: A etiologia da doença renal com apresentação na idade pediátrica é diferente da doença com apresentação na idade adulta. A nossa taxa de abandono, bem como a diminuição média anual da taxa de filtração glomerular são menores do que as registadas por unidades sem modelo de transição implementado. A maioria dos doentes que optou por hemodiálise iniciou técnica por fistula. Mais estudos são necessários nesta área

Sixty-eight isolates of Phaeomoniella chlamydospora obtained from symptomatic esca and Petri disease grapevines, obtained mostly within the Portuguese Dão appellation, were investigated regarding their phenotypic and molecular diversity, in order to determine intraspecific variability and population structure. Phenotypic features such as texture, colour, growing margin zonation, hyphal morphology and diameter growth were evaluated. Molecular characterization was performed through the sequencing of the total ITS region and molecular analyses were used to infer phylogenetic relationships, using the Maximum Likelihood approach. Isolates were divided into two groups, by both phenotypic and molecular analysis, but no clear correspondence was found between the two approaches. Nevertheless, both phenotypic and molecular analysis revealed a strong homogeneity among all isolates, despite their geographical origin, year of isolation and scion/rootstock combination, therefore supporting the clonal reproduction strategy described for this species.

Submitted by Licínia Santos (biblioteca@fba.ul.pt) on 2017-05-30T10:15:52Z No. of bitstreams: 2 ULFBA_MateriaPrima_V3N2_CAPA.jpg: 614282 bytes, checksum: f2878bede43e698b0c5fe446db70ac37 (MD5) ULFBA_Materiaprima_V3N2_p142-153.pdf: 213374 bytes, checksum: ae12ebcceab4ac21c0137a8e2c95f45e (MD5) Made available in DSpace on 2017-05-30T10:15:52Z (GMT). No. of bitstreams: 2 ULFBA_MateriaPrima_V3N2_CAPA.jpg: 614282 bytes, checksum: f2878bede43e698b0c5fe446db70ac37 (MD5) ULFBA_Materiaprima_V3N2_p142-153.pdf: 213374 bytes, checksum: ae12ebcceab4ac21c0137a8e2c95f45e (MD5) Previous issue date: 2015-07 info:eu-repo/semantics/publishedVersion

O presente artigo tem como objetivo apresentar os resultados de uma investigação com uma criança com Necessidades Educativas Especiais. Depois da caraterização da criança e dos contextos, partimos para uma intervenção estruturada, numa dinâmica de planificação, ação, avaliação e reflexão, geradora de práticas educativas diferenciadas e impulsionadoras do uso das tecnologias de informação e comunicação, através da utilização do software GeoGebra, como facilitador na aprendizagem da matemática, na qualidade de software educativo. Pretendemos aumentar a eficiência na realização de tarefas, diminuir as limitações e desenvolver ao máximo as capacidades da criança. Os resultados alcançados indicam-nos que a criança ao longo das sessões conseguiu ultrapassar com mais facilidade algumas das suas limitações, pelo que o software GeoGebra se revelou promotora de sucesso nas aulas de matemática Abstract - This article aims to present the results of an investigation with a child Special Educational Needs. After the characterization of children and contexts, we left for a structured intervention in a dynamic planning, action, evaluation and reflection, generating differentiated educational practices and driving the use of information and communication technologies through the use of GeoGebra software, as facilitator in the learning of mathematics (educational software). We intend to increase the efficiency in performing tasks, reducing the limitations and to fully develop the capacities of the child. The results indicate us that the child throughout the sessions could more easily overcome some of their limitations, so the GeoGebra software revealed a promoter of success in math classes.

Vascular access problems are an important cause of compulsory transfer to peritoneal dialysis. Surprisingly, little is known about the effect of these transfers on peritoneal dialysis adequacy, patient or technique survival. We have analysed retrospectively a cohort of 75 patients treated at the Peritoneal Dialysis Unit of Centro Hospitalar Lisboa Norte - Hospital de Santa Maria during the year 2011. ‘Vascular access problems’ were defined clinically. Patient characteristics, peritoneal dialysis features and survival were compared between patients with (group 1, n = 14) and without vascular access problems (group 2, n = 61). In group 1, significantly more patients were Black and had been transferred from haemodialysis, with a considerably longer time spent on this technique. These patients were more likely to be anuric, with an inferior daily total fluid removal, lower renal and total creatinine clearance, and poorer Kt/V for urea. Peritoneal clearance and peritoneal membrane transport type did not differ between groups. Group 1 had a considerably higher exit site infection and peritonitis rate, and a lower albumin level. No significant differences were observed in unadjusted patient or technique survival between the two study groups. In the Cox multiple regression model, only a higher total creatinine clearance significantly and positively influenced the technique survival. In conclusion, the prevalence of vascular access problems of the Peritoneal Dialysis Unit was 18.7% and it justified 78.6% of transfers from the Haemodialysis Unit. These were not the ideal patients for peritoneal dialysis. Nonetheless, our data suggest that the outcome (patient and technique survival) of patients with mandatory transfer to peritoneal dialysis because of vascular access problems is similar to that achieved in patients without vascular access problems. Total creatinine clearance appeared as an independent protective factor of technique survival Os problemas de acesso vasculares sao uma causa importante de transferencia obrigatoria para dialise peritoneal. Surpreendentemente, pouco e conhecido sobre os efeitos destas transferencias na adequação da dialise peritoneal, sobrevida do paciente ou da tecnica. Analisamos retrospetivamente um grupo de 75 pacientes tratados na Unidade de Dialise Peritoneal do Centro Hospitalar Lisboa Norte - Hospital de Santa Maria no ano 2011. Os ‘problemas de acesso vascular’ foram definidos clinicamente. As caracteristicas e sobrevida dos pacientes foi comparada entre os doentes com (grupo 1, n = 14) e sem problemas de acesso vascular (grupo 2, n = 61). No grupo 1 havia um numero maior de doentes de raca negra e transferidos de hemodialise, com um tempo dispendido nesta tecnica consideravelmente superior. Estes doentes eram mais propensos a anuria, menor remocao total de fluidos/dia, menor depuracao de creatinina renal e total, e inferior Kt/V da ureia. A depuracao de creatinina peritoneal e o tipo de transportador de membrana peritoneal nao divergiu entre os grupos. As taxas de infeccao do orificio de saida e peritonite foram superiores no grupo 1, a albuminemia era menor nestes doentes. Nao se verificaram diferencas na sobrevida dos doentes ou tecnica (metodo >Kaplan-Meier). No modelo de regressao >Cox, apenas valores superiores de depuracao de creatinina total influenciaram de forma significativa e positiva a sobrevida da tecnica. Em conclusao, na Unidade a prevalencia de problemas de acesso vascular foi 18.7%, e isso justificou 78.6% das transferencias da Unidade de Hemodialise. Estes nao seriam os doentes ideais para dialise peritoneal. No entanto, os dados sugerem que a sobrevida (paciente e tecnica) de doentes com transferência obrigatoria para dialise peritoneal por problemas de acesso vascular e similar a de doentes sem problemas de acesso vascular. A depuracao de creatinina total surgiu como fator protetor independente da sobrevida da tecnica

We report a case of a non-infected right external iliac artery false aneurysm. The patient was a 44 year-old woman on chronic peritoneal dialysis had had an allograft nephrectomy 12 years before and who presented with acute abdominal pain. Ultrasound and CT-scan showed a saccular aneurysm arising from the right external iliac artery. A large false aneurysm was identified during surgery, from donor arterial vessel remaining in situ after graft nephrectomy. Resection of the false aneurysm, with ligation of the right external iliac artery and interposition of a femorofemoral graft was successfully performed, with an uneventful post-operative recovery. False aneurysms after renal allograft nephrectomy are very rare. To our knowledge, this is the longest reported period of time between na nephrectomy and clinical evidence of a false aneurysm. info:eu-repo/semantics/publishedVersion

Dissertação apresentada à Escola Superior de Educação do Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Educação Especial – Domínio Cognitivo e Motor A investigação que aqui se apresenta relaciona-se com as aprendizagens realizadas na matemática por parte de um sujeito com Síndrome de Williams. Durante muitos anos, e por experiência, considera-se que este sujeito não era capaz de realizar essas aprendizagens. Neste caso concreto, o foco da pesquisa é a educação monetária associada ao tema do pensamento algébrico no sentido de promover a aquisição de habilidades de manuseio do dinheiro, tendo suporte de aprendizagem as Tecnologias de Informação e Comunicação (TIC). A nossa questão de investigação passa por tentarmos saber se as tarefas relacionadas com o tema – Pensamento Algébrico – suportadas pelas TIC contribuem para a aprendizagem do Sistema Monetário Europeu (zona euro) por parte de um sujeito com Síndrome de Williams. Face à questão investigada, a metodologia utilizada é de natureza qualitativa, seguindo uma perspetiva interpretativa, recorrendo-se ao estudo de caso. O estudo foi desenvolvido durante nove meses do ano letivo 2014/2015 com um aluno a beneficiar de Educação Especial e a frequentar o sétimo ano de escolaridade. Como principais fontes de recolha de dados privilegiou-se oito fichas de resolução das tarefas de exploração monetária, recorreu-se também a uma aplicação informática com as mesmas tarefas de exploração e seguidamente investigou-se com situações de simulação do quotidiano, com o intuito de averiguar se sim ou não o uso do software surtiu algum efeito. Constatada a aquisição de habilidades complexas num período de tempo reduzido, os resultados obtidos demonstraram a eficácia da aplicação informática e dos procedimentos de ensino utilizados. A utilização de procedimentos informatizados revelou uma precisão e eficiência no registro automático das respostas, e a obtenção imediata dos resultados. Em termos gerais a comparação dos resultados obtidos nas tarefas realizadas das fichas de exercícios, nas tarefas da aplicação informática e na simulação de situações do quotidiano permitiram concluir que houve uma evolução significativa no desempenho do aluno ao nível dos padrões de repetição e crescimento através de tarefas matemáticas relacionadas com o sistema monetário europeu. Verificou-se que o desenvolvimento do pensamento algébrico pode ser promovido mediante uma aposta consistente nas Tecnologias de Informação e Comunicação, que comprovam ser um recurso eficaz ao serviço das aprendizagens. The research presented here is related to the learning achieved in mathematics by an individual with Williams Syndrome. For many years, and from experience, it is considered that this individual is not able to perform this learnings. In this case, the focus of research is monetary education associated with the theme of algebraic thinking to promote the acquisition of money-handling skills, with the support of Information and Communication Technologies (ICT). Our research question is: would the tasks related to the theme - algebraic thinking – and supported by ICTs contribute to the learning of the European Monetary System (Eurozone) by a subject with Williams Syndrome? To address the issue investigated the methodology used is qualitative, following an interpretative perspective, and resorting to case study. The study was developed during nine months in the academic year 2014/15 with a student benefiting from Special Education and attending the seventh grade. As main sources of data collection the research favoured eight resolution sheets of monetary exploration tasks, a computer application with the same operating tasks and, then, investigation using everyday simulation situations, in order to ascertain whether or not, the use of the software had some effect. Given the acquisition of complex skills in a short period of time, the results showed the effectiveness of the IT application and the teaching procedures used. The use of electronic procedures revealed precision and efficiency in automatic recording of responses, and the immediate delivery of results. Overall, the comparison of results obtained in the tasks performed in the exercise sheets, the computer application tasks and the simulation of everyday situations showed that there was significant progress in student achievement in terms of repeating patterns and growth through mathematical tasks related to the European Monetary System. It was found that the development of algebraic thinking can be promoted through a consistent commitment in Information and Communication Technologies, which prove to be an effective resource in the service of learning.

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2017 Submitted by Biblioteca da Faculdade de Medicina da Universidade de Lisboa (repositorio@medicina.ulisboa.pt) on 2018-04-03T14:04:04Z No. of bitstreams: 1 MiguelSCoelho.pdf: 1309220 bytes, checksum: 376375c75bba8d0795e0c6bc0764912b (MD5) Made available in DSpace on 2018-04-05T11:33:58Z (GMT). No. of bitstreams: 1 MiguelSCoelho.pdf: 1309220 bytes, checksum: 376375c75bba8d0795e0c6bc0764912b (MD5) Previous issue date: 2017

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2017 Submitted by Biblioteca da Faculdade de Medicina da Universidade de Lisboa (repositorio@medicina.ulisboa.pt) on 2018-03-13T14:34:17Z No. of bitstreams: 1 MariaJoaoNovais.pdf: 698822 bytes, checksum: 152d92966da648e40e3fa75ef55bcfc5 (MD5) Made available in DSpace on 2018-03-15T11:57:51Z (GMT). No. of bitstreams: 1 MariaJoaoNovais.pdf: 698822 bytes, checksum: 152d92966da648e40e3fa75ef55bcfc5 (MD5) Previous issue date: 2017

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2015 Submitted by Biblioteca da Faculdade de Medicina da Universidade de Lisboa (repositorio@medicina.ulisboa.pt) on 2017-01-11T15:26:58Z No. of bitstreams: 1 MariaIAMendes.pdf: 592209 bytes, checksum: 0c28992c9554fcc74fb885886cc219f8 (MD5) Made available in DSpace on 2017-01-11T17:01:13Z (GMT). No. of bitstreams: 1 MariaIAMendes.pdf: 592209 bytes, checksum: 0c28992c9554fcc74fb885886cc219f8 (MD5) Previous issue date: 2015

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2015 Submitted by Biblioteca da Faculdade de Medicina da Universidade de Lisboa (repositorio@medicina.ulisboa.pt) on 2016-10-12T09:59:47Z No. of bitstreams: 1 AnaJPTaveira.pdf: 409329 bytes, checksum: a7177efa6088e3f85407742cc5a265d8 (MD5) Made available in DSpace on 2016-10-12T10:33:40Z (GMT). No. of bitstreams: 1 AnaJPTaveira.pdf: 409329 bytes, checksum: a7177efa6088e3f85407742cc5a265d8 (MD5) Previous issue date: 2015

mestrado em Engenharia Química Este trabalho consiste no estudo das alterações das propriedades papeleiras através da modificação estrutural de pasta kraft de Eucalyptus globulus pela implementação de alta pressão hidrostática (TH) de modo a que as propriedades da pasta sejam as adequadas para a sua aplicação, papel tissue de baixa gramagem. Este trabalho consiste no estudo da aplicação da alta pressão hidrostática ao nível das fibras celulósicas de modo a verificar qual a influência que este tipo de tratamento apresenta nas propriedades papeleiras, tais como as mecânicas e estruturais. Assim, começou-se por implementar um TH em pasta kraft não refinada, tendo em estudo quatro gamas de pressão diferentes, 4000 – 7000 bar, numa pasta com uma consistência de 1,5%. Com esta aplicação verificaram-se melhorias nas propriedades mecânicas da pasta, sendo que os melhores resultados foram obtidos aquando aplicada uma pressão de 6000 bar, onde se obteve uma taxa de crescimento de 2% para o índice de rotura à tração, 1% no alongamento percentual na rotura, 1% no índice de rigidez à tração e 6% no índice de rebentamento, sendo que para estas propriedades esta gama de pressão foi a única que apresentou valores superiores ao da pasta referência. No índice de rasgamento, a única gama de pressão que apresentou uma taxa de crescimento positiva foi a 4000 bar, com cerca de 1%. De um modo geral, a pressão que apresentou melhores resultados foi a de 6000 bar, sendo esta a gama utilizada para a continuação dos estudos. De modo a verificar qual a influência da alta pressão na pasta kraft, foi refinada num moinho PFI em quatro gamas de refinação 0,500,1000 e 2000 revoluções, pasta sem tratamento de alta pressão e pasta sujeita prévio tratamento de alta pressão a 6000 bar. Assim, verificou-se que as propriedades mecânicas da pasta kraft aumentaram com o número de revoluções quer em pasta sujeita a TH quer em pasta somente refinada, embora estas sejam superiores para pasta somente refinada, à exceção do índice de rasgamento que apresenta uma taxa de crescimento de 41% para uma refinação de 500 revoluções em pasta sujeita a TH a 6000 bar e essa taxa de crescimento em pasta somente refinada só é atingida para uma refinação de 1000 revoluções. De um modo geral o tratamento hiperbárico não é vantajoso nas propriedades mecânicas quando aplicado em conjunto com a refinação. De modo a compreender melhor o efeito da alta pressão, foi feito um estudo ao grau de cristalinidade em pasta somente sujeita a alta pressão e em pasta refinada com prévio TH a 6000 bar. Neste estudo verificou-se que quando aplicada o TH a 4000 bar o grau de cristalinidade diminui, aumentando para as pressões seguintes progressivamente, facto este que se deve a ocorrência de rearranjos ao nível das cadeias de celulose, uma vez que as zonas paracristalinas sofrem recristalização. O mesmo não acontece na pasta refinada com prévio TH a 6000 bar, pois o grau de cristalinidade diminui, o que se pode dever ao facto da refinação degradar a parede celular. Como o futuro da indústria de pasta de papel está cada vez mais direcionado para papéis de baixa gramagem, papel tissue, foi inserido neste trabalho uma componente de estudo das alterações das propriedades papeleiras deste tipo com a aplicação da alta pressão hidrostática. Ao realizar este estudo verificou-se que a velocidade e a capacidade de absorção é superior no caso da pasta refinada sujeita a prévio TH a 6000 bar em relação à pasta somente refinada. A maciez apresenta o seu máximo em pasta não sujeita a qualquer tratamento, 86.2, diminuindo com a aplicação da alta pressão, tendo o seu mínimo para uma pressão de 5000 bar, 81,8, voltando a aumentar até atingir a pressão de 7000 bar. This work consists in the study of the changes of the paper proprieties through the structural modification of the kraft pulp coming from Eucalyptus globulus by the implementation of high hydrostatic pressure (HT) so that the proprieties of the pulp be the suitable ones to its application, tissue paper of low grammage. This work aims at studying the application of the HT concerning the level of the cellulosic fibres in order to check which influence this kind of treatment presents in the paper proprieties, such as the mechanic and structural ones. Thus, a HT was first implemented in the kraft pulp which was not refined, having studied from ranges of different pressures, from 4000 to 7000 bar, in a pulp with a consistency of 1,5%. With this application some improvements were noticed concerning the mechanic proprieties of the pulp and the best results were obtained when a pressure of 6000 bar was applied, during which is obtained a raise of 2% for the tensile breaking length, 1% for the percentage on the elongation at break, 1% for the tensile strength and 6% for the burst index, having in mind that for these proprieties this range of pressure was the only one which presented values that were superior to the ones of the pulp reference. In the tear index, the only pressure range that presented a positive growth rate was the 4000 bar with about 1%. In a general way, the pressure that presented the best results was the one of 6000 bar which was the one used to the keeping on of studies. In order to verify which was the influence of the high pressure in the kraft pulp, this one was refined in a PFI mill according to four ranges of refining: 0,500,1000 and 2000 revolution, pulp without HT and pulp subjected to previous HT according to 6000 bar. Thus, it was noticed that the mechanical proprieties of the pulp were increased according to the number of revolutions in both kinds of pulps although these mechanical proprieties are superior in a pulp which is only refined, except the tear index which presents a growth rate of 41% concerning a refining of 500 revolutions in the pulp subjected to a HT according to 6000 bar. This growth rate concerning the pulp that is only refined is only obtained according to a refining of 1000 revolutions. In a general way the HT is not advantageous in the mechanical proprieties when it is applied together with the refining. In order to better understand the effect of the HT, a study was done to the level of crystallinity in the pulps only subjected to the HT and in the refined pulp with a previous HT according to 6000 bar. In this study it was applied a HT according to 4000 bar and that it increased when the following pressures where progressively increased, which was due when some rearrangements were done at the level of the cellulose chains, since the paracrystallines areas go through recrystallization. The same does not happen in the refined pulp submitted to a previous HT according 6000 bar, because the level of crystallinity decreases, which is due to the fact that the cell wall. As the future of the pulp industry is directing itself to low grammage paper, tissue paper, it was inserted in this work a study component that changes the papermaking properties of this type of paper using the application of high hydrostatic pressure . In the process of this study we found that the speed and absorption capacity is higher in the case of refined pulp with a previous HT according to 6000 bar relative to the refined pulp alone. The softness presents its maximum in the pulp not subjected to any kind of treatment 86,2, decreasing according to an application of HT, having its minimum according to a pressure of 5000 bar, 81,8, starting increasing again till it reaches a pressure of 7000 bar.

Mestrado em Engenharia Química Este trabalho constou num estudo da modificação da pasta kraft de eucalipto, utilizando uma técnica de processamento por alta pressão hidrostática com o intuito de melhorar a sua performance para novas aplicações tal como o papel tissue ou o papel para embalagens. Para tal pretendia-se melhorar algumas propriedades da pasta com a utilização da técnica de alta pressão hidrostática. Realizou-se um estudo preliminar onde se submeteu uma pasta branqueada A, não refinada, a um tratamento hiperbárico (TH) numa gama de pressões de 5000-8000 bar. Para uma pressão de 6000 bar constatou-se uma melhoria de cerca de 16 % no alongamento percentual na rotura, 17 % na resistência à tração, 27 % no índice de rebentamento e cerca de 19 % no índice de rasgamento. Posteriormente, e tendo em conta os resultados positivos verificados na pasta A, estudou-se o efeito do TH numa pasta branqueada B variando a consistência de tratamento (1,5% ou 3%) e o tempo de processamento (5 ou 10 minutos). Foi estudado também o efeito do TH quando aplicado antes e após a refinação da pasta. A pasta branca foi submetida à refinação num moinho PFI entre 1000 e 3000 rotações. Os resultados obtidos mostram que o TH realizado a menores consistências apresenta um efeito mais significativo nas propriedades físico-mecânicas de pastas e que o efeito é distinto quando o processamento é aplicado antes e depois da refinação, tendo-se registado melhoramentos das propriedades mecânicas apenas quando o TH ocorre após a refinação. A pasta kraft foi também modificada com anidrido alquenil succínico (ASA). A modificação da pasta de celulose com ASA resultou numa diminuição das propriedades mecânicas e para além disso não gerou qualquer alteração na termoplasticidade do material, no entanto registou-se um aumento na resistência à molhabilidade. Concluiu-se que o TH conduz a alterações ao nível de propriedades mecânicas e estruturais da pasta de interesse para a aplicação em papéis tissue no caso da pasta B. Para além disso a modificação da pasta com ASA resultou em alterações de interesse particular para papéis de embalagem. This work consisted on the study of the modification of a eucalyptus kraft pulp by using a high hydrostatic pressure processing technique in order to improve its performance for new applications such as tissue paper or packing paper. It was done a preliminary study where a bleached unrefined pulp (A), was submited to a hyperbaric treatment (HT) in a pressure range of 5000 to 8000 bar. For a pressure of 6000 bar it was found an improvement of approximately 16% percentage on the elongation at break, 17% in the tensile strength, 27% in the burst index and approximately 19% in the tear index. Subsequently, in view of the positive results observed in the paste, it was studied the effect of TH in a bleached pulp (B) by changing the processing consistence (1.5% or 3%) and the processing time (5 or 10 minutes) . It was also studied the effect of the HT when applied before and after the pulp refining. The white pulp was subjected to refining in a PFI mill between 1000 and 3000 revolutions. The results obtained have shown that the HT performed at lower consistencies result in the most significant effect on the physical and mechanical properties of the pulp and that the effect is distinct when the processing is applied before and after the refining, having recorded improvements of mechanical properties only when HT occurs after refining. The kraft pulp was also modified with alkenyl succinic anhydride (ASA). The modification of the cellulose pulp with ASA resulted in a decrease of mechanical properties and moreover did not cause any change in the material thermoplasticity, however there was an increase in resistance to wettability. The conclusion was that th HT leads to changes in the mechanical and structural properties of the pulp, which are of interest for use in tissue paper in the case of pulp B. In addition to the modification of the pasta ASA resulted in changes to particular interest for packing papers.