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- Application of gauge theory to finance: a systematic literature reviewPublication . Rodrigues, Nelson Deus; Pintassilgo, Pedro; Viegas, CristinaIn this dissertation, a systematic literature review was undertaken, exploring the application of gauge theory, an important formalism in physics literature, to finance. A set of keywords pertaining both gauge theory and finance were established and used as a search string in the database Web of Science. After exclusion and inclusion principles were applied to the set of articles generated, 14 papers were obtained. By systematically reviewing them, three major approaches to a financial gauge theory were found: Beliefs-Preferences Gauge Symmetry, Local Num´eraire Gauge Symmetry, and Deflator-Term Structure Gauge Symmetry. These can be essentially differentiated by the kind of gauge symmetry explored. Changing pairs of beliefs and preferences, local num´eraires and pairs of deflator and term structure is argued to be of no consequence to the dynamics of the financial market under consideration. A differential geometric treatment of financial markets as fibre bundles was shown to be necessary for an understanding of the gauge theory application, and proved itself to be successful in rethinking certain concepts, such as gains from arbitrage opportunities, being equivalent to the curvature of the said fibre bundle, an invariant under gauge transformations. The local num´eraire gauge symmetry turned out to be the most investigated one, leading to the execution of various numerical simulations, each with different added variations. Amongst them, the idea of using path integrals, a formalism from quantum mechanics, as a way of simulating the log price probability distributions of a market is used. This works by assuming that the market is characterized by the minimization of arbitrage opportunities. It was found good agreement with historical data, which substantiates the existence of gauge symmetry in financial markets, at least to some extent.
- A perturbação do espectro do autismo: contribuições para o estudo da sobrecarga, ansiedade, depressão, stresse, qualidade de vida e resiliência nas famíliasPublication . Conceição, Nélia de Jesus Marreiro Costa da; Martins, Maria Helena Venâncio; Carmo, Cláudia Isabel GuerreiroO nascimento de um filho é algo maravilhoso, mas que pode trazer grandes dúvidas e inseguranças. Quando um filho apresenta uma perturbação como a Perturbação do Espectro do Autismo ( essas dúvidas e inseguranças são acres cidas de uma grande carga emocional que, muitas vezes pode levar a que as famílias entrem em rutura. Assim, a sobrecarga familiar e a sintomatologia depressiva são em numeroso s casos uma presença constante na vida destas famílias. Alguns estudos re velam c ontudo que algumas famílias conseguem reorganizar se e lidar adaptativamente com as dificuldades provenientes desta situação utilizando estratégias que lhes permit em ser mais resilientes. O objetivo d este estudo consiste em analisar a dinâmica d as famíl ias com filhos com PEA explorando as relações entre a sobrecarga, indicadores de saúde mental (ansiedade, stresse e depressão) depressão), qualidade de vida ( e resiliência, e comparando as com pais de crianças com um desenvolvimento normativo. Para tal utilizou se um q uestionário sociodemográfico, a Escala de Desgaste do Cuidador Familiar (EDC F ), a Escala de Ansiedade, Depressão e Stresse (EADS), a EUROHIS QOL 8 e a Family Resilience Assessment Scale ( numa amostra constituída por pais e principais cuidador es de crianças entre os 4 e os 16 anos com PEA n 49) e com desenvolvimento normativo ( n 76 Os resultados desta investigação demonstra m que os pais de crianças com PEA apresentaram níveis mais elevados de sobrecarga e sintomatologia depressiva e qu e os pais de crianças com desenvolvimento norma tivo apresentaram níveis mais elevados de crescimento pessoal resiliência familiar e uma melhor QdV As variáveis que predizem u ma maior sobrecarga no s pais de crianças com PEA são o stresse, a ansiedade e a d epressão , destaca ndo se ao nível da so brecarga nas relações uma correlação negativa moderada muito significativa com a QdV e uma correlação negativa forte muito significativa com a resiliê ncia na dimensão d as ligações familiares
- A Escala de sentimento de competência parental (PSOC): características psicométricas numa amostra de mães e pais portugueses de famílias em risco psicossocialPublication . Freitas, Délia Cristina Dias; Nunes, CristinaAs competências parentais percebidas são uma das dimensões da parentalidade mais relevante no âmbito das intervenções psicossociais e na avaliação do contexto familiar. Por este motivo é importante que investigadores e profissionais disponham de instrumentos de medida fiáveis, de fácil aplicação e adaptados à população em estudo. A Escala de Sentimento de Competência Parental (PSOC) é uma das mais utilizadas para medir o sentimento de eficácia e satisfação parental, existindo apenas uma validação portuguesa adaptada às famílias em risco. Além disso, existem diversos estudos que apontam soluções fatoriais diferentes, com uma grande disparidade sobre as propriedades psicométricas da escala. Neste estudo, avaliou-se o ajustamento do modelo de medida da PSOC, através da Análise Fatorial Confirmatória, numa amostra de mães e pais portugueses de famílias em risco psicossocial (N = 273). Os resultados mostraram que a solução de dois fatores, eficácia e satisfação, constituída por dez itens, estando divididos cinco itens por cada fator, revelou um ajustamento mais adequado e melhor fiabilidade compósita. Na sua generalidade, os resultados demonstram que os itens são homogéneos e que a escala mede consistentemente as características para a qual foi criada, comprovando as boas características psicométricas da PSOC versão reduzida.
- Deciphering the effects of metal-based drugs on cell signaling pathways in cancer cellsPublication . Babych, Kateryna; Marques, Vera Linda Ribeiro; León, Ignacio E.The term „cancer‟ encompasses a large group of diseases that are characterized by the development of abnormal cells, which divide, grow and spread without control in any part of the organism, spreading through blood or lymph vessels into surrounding tissues. Chemotherapy is a type of cancer treatment that uses drugs to kill cancer cells and is focused on stopping or slowing the growth of cancer cells, which divide abnormally and causes tumors. In most of the cases of chemotherapy prescription and selection of the specific drug, the more effective is a combination of two or more medications that, preferentially, should not interact with each other, either on their mechanism of action and/or their metabolism and elimination. Second and third generations of the existing drugs show increased bioactivity against cancer, but side effects are still a matter of concern. Recent studies show a significant interest in metal-based drugs, with some existing drugs being used already as antitumor agents, with proven effectiveness and fewer side effects, comparing to other drug treatments. Copper(II) as a metal and its complexes with various organic compounds have been reported to show cytotoxic activity at low concentrations. The aim of this work is to examine the effects of newly synthesized copper complexes in human cancer cell lines, both in terms of cytotoxicity and of mechanism of action. In this research work, two copper(II) based compounds were (copper(II)-tropolone and copper(II)-hinokitiol complexes), for their cytotoxic properties and tested in the human mammary breast cancer cell line MCF7 and MDA-MB-231 for their effect on viability, oxidative stress, apoptosis and interaction with DNA. Additionally, as a model for in vivo studies, the 3D model testing on cell viability was conducted and showed a positive result against MCF7 cell line survival. Together with that, the comparative analysis of complexes, its ligands and copper salt was performed. These compounds showed quite promising results in terms of their potential effect as antitumor drugs.
- A música como estratégia para o desenvolvimento da consciência silábica em crianças de 4 e 5 anosPublication . Diogo, Raquel Horta; Horta, Maria Helena Martins da Cruz; Matos, Isabel Maria Gomes Garcia deO presente relatório de investigação intitula-se “A música como estratégia para o desenvolvimento da consciência silábica em crianças de 4 e 5 anos” e foi realizado no âmbito da unidade curricular Prática de Ensino Supervisionada (PES), no ano letivo 2018/2019. A presente investigação realizou-se numa instituição de cariz privado, no concelho de Loulé, distrito de Faro. A música revela-se de extrema importância para o desenvolvimento global da criança e, sendo uma forma de comunicação universal, deve ser estimulada desde muito cedo. Consequentemente percebe-se que a aprendizagem da música tem uma forte ligação com a aprendizagem da linguagem, na qual a sua aprendizagem antecipada contribuirá para o desenvolvimento da consciência fonológica (Matos, 2013). Assim, colocou-se a seguinte questão de investigação: “Será a música um bom recurso para desenvolver a consciência silábica em crianças de 4 e 5 anos?”. A presente investigação baseia-se num projeto de investigação-ação, num paradigma de natureza quantitativa, cuja amostra é constituída por cinco crianças em que uma têm 4 anos e as restantes quatro crianças têm 5 anos de idade. Entre os dois momentos (pré-teste e pós-teste), foi realizado um plano de intervenção pedagógica constituído por quatro estratégias ao nível da consciência silábica com o recurso à exploração de uma canção infantil em grande grupo. O grupo de cinco crianças demonstraram uma melhoria nos resultados obtidos nos pós-testes comparativamente aos evidenciados no pré-teste, confirmando deste modo, que as crianças vivenciaram uma canção e realizaram atividades com base na mesma contribuindo, assim, para o desenvolvimento da consciência silábica.
- Pharmacogenetic analysis of inter-ethnic variability in the uptake transporter SLCO1B1 gene in colombian, mozambican, and portuguese populationsPublication . Nega, Mulata Haile; Marques, Vera Linda RibeiroAs atividades de enzimas metabólicos e transportadores de fármacos determinam, em larga medida, a resposta ao fármaco e a sua eliminação. A etnia é uma variável demográfica importante que contribui para a variabilidade interindividual no metabolismo e transporte de fármacos. Como resultado de diferenças étnicas na prevalência de polimorfismos de nucleótido único (SNP), pode ocorrer maior risco de eventos adversos, falha do tratamento ou prevalência de patologias em algumas populações. Os transportadores de influxo são um dos principais factores que contribuem para o processo de eliminação de fármacos. Foi demonstrado que os genes que codificam esses transportadores de influxo são polimórficos. O OATP1B1 é um transportador de influxo conhecido por mediar a captação de vários compostos endógenos e xenobióticos. Várias variantes foram descritas no gene SLCO1B1 que codifica o OATP1B1. Entre estas, a variante mais estudada, c.521T> C, foi descrita como estando significativamente associada ao risco de miopatias induzidas pela terapêutica com estatinas. Apesar da clara relevância clínica desta variante polimórfica, um número reduzido de populações foram caracterizadas. Até o momento, não existem dados epidemiológicos para a variante SLCO1B1 c.521T> C nas populações colombiana, moçambicana e portuguesa. Este estudo teve, assim, como objetivo, avaliar as frequências genotípicas e alélicas da variante SLCO1B1 c.521T> C em voluntários saudáveis colombianos, moçambicanos e portugueses. O DNA genómico isolado de amostras de sangue obtidas, sob consentimento informado, de 67 indivíduos colombianos, 53 moçambicanos e 61 portugueses foi analisado para este polimorfismo através de um novo método de genotipagem por PCR-RFLP. Um total de 47 (70,15%), 12 (17,91%) e 8 (11,94%) dos 67 indivíduos colombianos, 47 (88,68%), 5 (9,43%), 1 (1,89%) dos 53 indivíduos moçambicanos e 40 (65,57%), 16 (26,23%), 5 (8,20%), dos 61 indivíduos portugueses eram portadores do genótipo T / T-homo, C / T-hetero e C / Chomozigota, respectivamente . Em termos de frequências alélicas, observou-se um total de 106 alelos T (79,1%) e 28 alelos C (20,9%) em indivíduos colombianos; 99 alelos T (93,4%) e 7 alelos C (6,6%) C em moçambicanos e 96 alelos T (78,7%) e 26 alelos C (21,3%) em indivíduos portugueses. As frequências observadas em moçambicanos mostram uma diferença estatisticamente significativa em relação às observadas em colombianos (p=0,0017) e portugueses (p=0,0022). Por outro lado, as frequências observadas na amostra da população colombiana não são significativamente diferentes (p=1.000) em relação às observadas em Portugal. Em conclusão, os nossos dados demonstraram que o genótipo homozigota T / T é altamente prevalente, o genótipo homozigota variante, C / C, apresenta a menor frequência em moçambicanos, sendo por outro lado relativamente frequente em populações colombianas e portuguesas. Como resultado, indivíduos (principalmente caucasianos) com o genótipo homozigótico variante c.521C/C podem ser altamente suscetíveis a efeitos adversos relacionados à estatina do que aqueles com o genótipo c.521TT (referência) para o SNP c.521T> C.
- Evaluation of schiff bases and its metal complexes with potential therapeutic applicationsPublication . Tekamo, Israel Alemayehu; Correia, Isabel; Cavaco, IsabelMetal-based drugs have drawn significant attention over the past few decades due to their advanced properties and benefits in biomedical therapeutic and diagnostic systems. In the current work two Schiff bases, 4-methyl-2,6-bis-(pyridin-2-yl-hydrazonomethyl)-phenol (L1), and methyl-phenol-di-S-methyl dithiocarbazate (L2), and their corresponding zinc complexes, [Zn2(L1)(OAc)3] (C1) and [Zn2(L2)(OAc)] (C2) (OAc: CH3COO−) were synthesized. All compounds were characterized by elemental analyses, FTIR, UV–Vis and NMR spectroscopies and ESI-MS spectrometry. The stability of the compounds was evaluated under physiological conditions (5 % DMSO and 95 % PBS, pH 7.4). The interaction of Schiff bases and their corresponding Zn(II) complexes with biomolecules namely, bovine serum albumin (BSA) and calf thymus DNA (ctDNA) was investigated using UV-Vis, circular dichroism (CD) and fluorescence spectroscopies under physiological pH and 298 K. Fluorescence quenching of BSA upon interaction with the compounds was analysed using the Stern-Volmer formalism which revealed moderate to strong binding to serum albumin with binding constant values of KB=2.36x103 and 2.38x105M−1, for C1 and C2 respectively. These results reveal good binding propensity in comparison with the ligands. Changes in the secondary structure of BSA are imposed by the Schiff base ligands and Zn(II) complexes as revealed by CD spectroscopy. Additionally, hypochromicity in the UV-Vis absorption spectra of the complexes upon addition of BSA further corroborates interaction between the protein and the complex. The complexes were tested for their DNA binding ability by UV-Vis and CD spectroscopy and the results indicate that there is interaction between the complexes and DNA where C1 has better binding tendency toward DNA than C2. Cytotoxic activity of L1 and L2 studied with several tumour cell lines (Caco-2, MCF-7 and PC-3) and normal cell, NHDF, showed that the compounds are cytotoxic to all cell lines tested, without selectivity towards cancer cells. Overall, the IC50 values are comparable with the ones obtained for the positive control, fluorouracil. The two ligands and one complex were tested against several strains of bacteria and fungi and promising results were obtained, where L1 is active against L. monocytogenes, L2 is active against K. pneumoniae, A. baumannii and S. aureus and C1 against L. monocytogenes and S. aureus. L2 showed better activity against the tested microorganisms compared to L1 and the metal complex.
- Life history parameters and valorisation of a low commercial value fish species: the case study of piper gurnard, Trigla lyra Linnaeus 1758Publication . Sousa, Inês Mendes de Andrade Araújo de; Sequeira, Vera; Andrade, José PedroMany fishing activities involve high discarding rates constituting, a major problem for the marine ecosystem. Trigla lyra presents low commercial value in Portuguese landings and is mainly caught as accessory species in trawls, trammel nets, traps and pots. Published information on this species in Portuguese waters is scarce. So, the main objectives of the present study are to contribute to the knowledge of biological, namely age and growth and reproduction, and chemical parameters of T. lyra. Approximately 30 specimens were collected monthly from fishing vessels operating off Peniche (West coast of Portugal). The study of age and growth involved age estimation using whole sagitta otoliths, marginal increment ratio (MIR) and otolith edge type analysis, determination of length-weight relationship and estimation of parameters of the von Bertalanffy growth model. Regarding reproduction, the structure of the gonads was studied, and reproductive strategy was characterized, including the definition and duration of spawning season and determination of fecundity type. Chemical composition of the muscle was determined in terms of moisture, ash content, protein content, total fat and profile of fatty acids. MIR and otolith edge type analysis suggest that a single set of translucent and opaque increments is formed every year in T. lyra otoliths. There was a lack of small individuals in the sample, leading to the application of three adjustment methods for estimating growth parameters, with back-calculation being the best method. Sex ratio analysis indicated higher abundance of females in relation to males. Spawning season occurred between November and February and fecundity type was found to be determinate. The species proved to be beneficial regarding protein content but especially regarding fatty acid content, with the results indicating high EPA and DHA concentrations. The present study contributed to improve the knowledge on biological and chemical parameters of T. lyra in Portuguese waters, essential for its exploration and future valorisation.
- Study of different strategies and approaches followed by footwear companies in vietnam to comply with reach regulationPublication . Chau, Nguyen Le Minh; Cavaco, Isabel; Sainz, DanielThe European Registration, Evaluation, Authorization and Restriction of Chemical (REACH) is the world’s most ambitious initiative governing the use of chemicals not only on their own but in mixtures or articles. REACH assures the supply of safe products that do not present any hazards to end users or if there is a hazard, it must be communicated properly along with risk management plans. Theoretically, REACH compliance is only mandatory for European companies. In fact, REACH could influence company’s activities beyond its border through economic interdependence. Outsourced manufacturing is a good example as European buyers play an important role on fostering REACH application in other countries. By taking advantages of low labor cost and favorable tariff reduction from Free Trade Agreements (FTAs) which Vietnam has signed with Europe, Vietnam becomes an attractive outsourcing destination of many European footwear buyers. Since “made in China” is no longer cheap, it could be foreseen that Europeans would soon move their manufacturing to Vietnam which is now maintaining the second position after China. However, there is a risk that Vietnam loses its opportunity due to REACH compliance issues. REACH compliance is not easy and it is much more challenging in developing countries, where gaps in technologies and stringency of standards each country applies are encountered. The objective of this thesis has been to assess the difficulties felt by Vietnamese companies, in particular footwear companies, when faced with the requirements of REACH regulations. To address the compliance situation in Vietnam, an online survey was developed and disseminated to Vietnam footwear suppliers with the support of Vietnam Leather, Footwear and Handbag Association (LEFASO) and Decathlon (a European brand having its manufacturing in Vietnam). The survey has sets of questions that allow the researcher to assess Vietnam footwear supplier’s awareness of REACH regulation, particularly, Substances of Very High Concern (SVHCs) communication obligations and Restricted Substances (RS) management. The survey also digs into difficulties Vietnam footwear suppliers are facing as well as solutions they are applying to overcome these difficulties. None of LEFASO’s company member participated in the survey. Out of suppliers of Decathlon in Vietnam, only 13 companies responded. The results of the study are largely based on these answers. Data from the survey reveals that almost all of the suppliers are familiar with the REACH regulation and aligning REACH requirements to their operations. Major concerns identified by suppliers when trying to comply with REACH regulation are costs of testing products against chemical lists, lack of knowledge of where regulated chemicals are introduced to the supply chain and frequent addition of new chemicals in the regulated list. These issues would be resolved if information of chemical compositions of materials supplied to the industry is made available. Although suppliers are coming up with individual processes to improve information flow throughout their supply chain, there are still shortcomings which would become another problem in the future. In the light of that, an approach proposed by the researcher is also discussed in the study to tackle both current and foreseeable problems