A intera����o das marcas com o p��blico atrav��s do Facebook: o mercado dos smartphones e as marcas Samsung e Apple

Disserta����o de Mestrado apresentado ao Instituto de Contabilidade e Administra����o do Porto para a obten����o do grau de Mestre em Marketing Digital sob orienta����o de Sandrina Teixeira Anabela Ribeiro

Difficulties in diagnosing atypical primary HIV-1 infection

Several cases of primary HIV-1 infection are not identified, either because the diagnosis is not suspected or because they test negative for HIV-1 antibody. This work presents an uncommon case of primary HIV-1 infection in an young parenteral drug abuser man, who presented symptoms of acute hepatitis. During the initial acute phase the serum sample of the patient tested negative for the presence of antibodies against several viruses, including HIV-1. Nevertheless, the diagnosis of primary HIV-1 infection was suspected by using an alternative method for"in vitro" induced antibody production (IVIAP), and confirmed by p24 antigen serum positivity and seroconversion in serial plasma samples of the patient. The authors suggest the use of the IVIAP and others complementary assays to help the diagnosis of acute HIV-1 infection in persons at high risk conditions.

Influ��ncia do teor de ��gua no comportamento de materiais de constru����o

Disserta����o para obten����o do grau de Mestre em Engenharia Civil ��� Perfil de Constru����o

Novas linhas celulares humanas para produ����o de adenov��rus com aplica����o em terapia g��nica

Disserta����o apresentada para a obten����o do Grau de Mestre em Gen��tica Molecular e Biomedicina, pela Universidade Nova de Lisboa, Faculdade de Ci��ncias e Tecnologia

Agreement between premortem and postmortem diagnoses in patients with acquired immunodeficiency syndrome observed at a brazilian teaching hospital

Acquired immunodeficiency syndrome (AIDS) is one of the main causes of death in adults worldwide. More commonly than in the general population, in patients with AIDS there is substantial disagreement between causes of death which are clinically suspected and those established by postmortem examination. The findings of 52 postmortem examinations were compared to the premortem (clinical) diagnoses, and there was 46% agreement between them. Fifty two percent of the patients had more than one postmortem diagnosis, and 48% had at least one AIDS-related disease not suspected clinically. Cytomegalovirus infection was the commonest (30.7%) autopsy finding, but not a single case had been suspected premortem. Bacterial infection, tuberculosis, and histoplasmosis were also common, sometimes not previously suspected, postmortem findings. This study shows that multiple infections occur simultaneously in AIDS patients, and that many among them are never suspected before the postmortem examination. These findings suggest that an aggressive investigation of infections and cancers should be done in patients with AIDS, particularly in those who do not respond to therapy of an already recognized condition

SGQ nas empresas de constru����o portuguesas: identifica����o e an��lise das suas principais implica����es e factores impulsionadores

Disserta����o para a obten����o do Grau de Mestre em Engenharia Civil ��� Mestrado Integrado em Engenharia Civil - constru����o

Integra����o das quest��es ambientais na produ����o de instrumentos de gest��o territorial

Relat��rio de Est��gio apresentado para cumprimento dos requisitos necess��rios �� obten����o do grau de Mestre em Gest��o do Territ��rio com especializa����o em Ambiente e Recursos Naturais

Caracteriza����o de sistemas hidrotermais de baixa entalpia na Ribeira Grande, Ilha de S. Miguel, A��ores

Disserta����o para obten����o do Grau de Mestre em Engenharia Geol��gica - Georrecursos

Valoriza����o energ��tica de lamas resultantes do processo de produ����o de pasta e papel numa caldeira de leito fluidizado

Disserta����o para obten����o do Grau de Mestre Energia e Bioenergia

Electrospun Polyaniline-Reduced Graphene Oxide Composite Nanofibers Based High Sensitive Ammonia Gas Sensor

Ammonia is an important gas in many power plants and industrial processes so its detection is of extreme importance in environmental monitoring and process control due to its high toxicity. Ammonia���s threshold limit is 25 ppm and the exposure time limit is 8 h, however exposure to 35 ppm is only secure for 10 min. In this work a brief introduction to ammonia aspects are presented, like its physical and chemical properties, the dangers in its manipulation, its ways of production and its sources. The application areas in which ammonia gas detection is important and needed are also referred: environmental gas analysis (e.g. intense farming), automotive-, chemical- and medical industries. In order to monitor ammonia gas in these different areas there are some requirements that must be attended. These requirements determine the choice of sensor and, therefore, several types of sensors with different characteristics were developed, like metal oxides, surface acoustic wave-, catalytic-, and optical sensors, indirect gas analyzers, and conducting polymers. All the sensors types are described, but more attention will be given to polyaniline (PANI), particularly to its characteristics, syntheses, chemical doping processes, deposition methods, transduction modes, and its adhesion to inorganic materials. Besides this, short descriptions of PANI nanostructures, the use of electrospinning in the formation of nanofibers/microfibers, and graphene and its characteristics are included. The created sensor is an instrument that tries to achieve a goal of the medical community in the control of the breath���s ammonia levels being an easy and non-invasive method for diagnostic of kidney malfunction and/or gastric ulcers. For that the device should be capable to detect different levels of ammonia gas concentrations. So, in the present work an ammonia gas sensor was developed using a conductive polymer composite which was immobilized on a carbon transducer surface. The experiments were targeted to ammonia measurements at ppb level. Ammonia gas measurements were carried out in the concentration range from 1 ppb to 500 ppb. A commercial substrate was used; screen-printed carbon electrodes. After adequate surface pre-treatment of the substrate, its electrodes were covered by a nanofibrous polymeric composite. The conducting polyaniline doped with sulfuric acid (H2SO4) was blended with reduced graphene oxide (RGO) obtained by wet chemical synthesis. This composite formed the basis for the formation of nanofibers by electrospinning. Nanofibers will increase the sensitivity of the sensing material. The electrospun PANI-RGO fibers were placed on the substrate and then dried at ambient temperature. Amperometric measurements were performed at different ammonia gas concentrations (1 to 500 ppb). The I-V characteristics were registered and some interfering gases were studied (NO2, ethanol, and acetone). The gas samples were prepared in a custom setup and were diluted with dry nitrogen gas. Electrospun nanofibers of PANI-RGO composite demonstrated an enhancement in NH3 gas detection when comparing with only electrospun PANI nanofibers. Was visible higher range of resistance at concentrations from 1 to 500 ppb. It was also observed that the sensor had stable, reproducible and recoverable properties. Moreover, it had better response and recovery times. The new sensing material of the developed sensor demonstrated to be a good candidate for ammonia gas determination.

Preval��ncia de Obstru����o numa Popula����o Exposta ao Fumo do Tabaco - Projecto PNEUMOBIL

A espirometria n��o atingiu ainda a divulga����o que se justificaria em patologia respirat��ria, ou indiv��duos que se encontram em risco relativamente a esta patologia, cujo diagn��stico �� insuficiente, havendo um escasso conhecimento, e consequente controlo, dos custos atribu��veis a estas doen��as, com destaque para a doen��a pulmonar obstrutiva cr��nica (DPOC). O PNEUMOBIL, iniciativa que visa esta divulga����o entre fumadores e ex -fumadores, foi reactivado, ap��s 10 anos de aplica����o em Portugal, revelando agora, numa amostra de 5324 indiv��duos, em que cerca de 50% ainda mant��m os h��bitos tab��gicos, sejam do sexo masculino ou feminino, que houve uma elevada preval��ncia de obstru����o detectada por espirometria (30% e 25%, respectivamente) nas pessoas rastreadas perto de centros de sa��de (grupo p��blico) e em empresas (grupo privado). Este risco n��o se explica em regra por exposi����o ocupacional, nem se relaciona com a maioria dos sintomas respirat��rios, muito frequentes nos rastreados. Apenas a dispneia (OR=1,28; p=0,02) e os epis��dios frequentes de expectora����o (OR=1,21; p=0,008) ou de bronquite aguda (OR=1,31; p=0,05) revelam alguma rela����o com a obstru����o. O reconhecimento pr��vio da DPOC �� muito reduzido e a presen��a de obstru����o n��o se correlaciona (p=0,204) com o assumir da condi����o de portador.

Infec����es por Tinea capitis em meios desfavorecidos da periferia de Lisboa - Estudo em crian��as do Bairro de Santa Filomena, Concelho da Amadora

PLAVRAS ��� CHAVE: Tinea capitis, colheita de amostras, diagn��stico laboratorial, question��rio, estrat��gias de interven����o Os fungos dermat��fitos est��o entre os mais disseminados e prevalentes das doen��as causadas por fungos, afectam milh��es de pessoas em todas as partes do mundo. A tinea capitis �� a infec����o f��ngica mais comum na idade pedi��trica, �� contagiosa, havendo aumento do risco de infec����o quando existe partilha de objectos e poucos cuidados de higiene. �� uma infec����o que afecta essencialmente crian��as e pr��-adolescentes, sendo que estes apresentam mais susceptibilidade e exposi����o �� infec����o. �� uma infec����o com distribui����o mundial, sendo muito comum em ��frica. Anteriormente as ��reas end��micas estavam mais definidas, mas com o aumento das viagens inter-continentais e da imigra����o novas doen��as t��m-se expandido nos pa��ses de acolhimento, da�� o aumento da preval��ncia desta infec����o nos pa��ses Europeus. Para al��m de ser uma doen��a com um impacto social marcado, levando as crian��as �� restri����o de actividades sociais, como a ida �� escola e todas as consequ��ncias que da�� adv��m, como por exemplo a exclus��o. Perante esta situa����o, realizou-se um estudo de forma a identificar a preval��ncia da tinea capitis em crian��as com idades entre os 1-14 anos no Bairro de Santa Filomena, Concelho da Amadora, Portugal, e os conhecimentos (defini����o, diagn��stico e tratamento) dos encarregados de educa����o/respons��veis pela crian��a sobre a doen��a, para se poderem tra��ar estrat��gias de interven����o. A popula����o era composta por 127 crian��as, que frequentavam a Associa����o da Encosta Nascente e o Centro de Catequese leccionado no Bairro de Santa Filomena, sendo 44,9% do Sexo Masculino e 55,1% do sexo Feminino, com idades pr��-escolar e escolar. Utilizaram-se tr��s t��cnicas de diagn��stico, observa����o cl��nica, microscopia e exame cultural. As amostras do couro cabeludo das crian��as foram analisadas no Laborat��rio de Micologia do Instituto de Higiene e Medicina Tropical. A preval��ncia de crian��as com doen��a activa foi de 17,3% e de portadoras 19,7%. Foram identificados dois agentes etiol��gicas, Microsporum audouinii e o Tricophyton soudanense (fungos de origem Africana). Aos encarregados de educa����o/respons��veis pelas crian��as aplicou-se um question��rio sobre aspectos relacionados com a infec����o por tinea capitis. Os respondentes mostraram poucos conhecimentos, alguns at�� incorrectos. Tendo em vista o controlo da infec����o, �� necess��rio envolver v��rios parceiros, como os Centros de Sa��de e Centros de Educa����o (Creches /Escolas/Catequese), para al��m dos encarregados de educa����o, intervindo na sua forma����o com Sess��es de Educa����o, rastreios, diagn��stico e tratamento, medidas preventivas e melhorias das condi����es de higiene pessoal e ambiental.

Deciding Kleene Algebra Terms Equivalence in Coq

This paper presents a mechanically verified implementation of an algorithm for deciding the equivalence of Kleene algebra terms within the Coq proof assistant. The algorithm decides equivalence of two given regular expressions through an iterated process of testing the equivalence of their partial derivatives and does not require the construction of the corresponding automata. Recent theoretical and experimental research provides evidence that this method is, on average, more efficient than the classical methods based on automata. We present some performance tests, comparisons with similar approaches, and also introduce a generalization of the algorithm to decide the equivalence of terms of Kleene algebra with tests. The motivation for the work presented in this paper is that of using the libraries developed as trusted frameworks for carrying out certified program verification.

Influ��ncia do nevoeiro salino na degrada����o de materiais cer��micos aplicados em constru����es

Disserta����o para obten����o do Grau de Mestre em Engenharia Geol��gica (Georrecursos)