Breve caraterização do porta-enxerto ‘Gou Tou’ e a sua adequação à citricultura portuguesa

Os porta-enxertos predominantes hoje na bacia do Mediterrâneo são as citranjeiras, sobretudo a ‘Carrizo’. A laranjeira ‘Gou Tou’ é considerada um híbrido natural de laranjeira azeda, e é um dos porta-enxertos mais comuns na China. Este híbrido pode contribuir para a diversificação dos porta-enxertos usados em Portugal e em países vizinhos. Parece ser tolerante à Tristeza, cresce bem em solos calcários, é tolerante à salinidade e à seca. O seu efeito sobre a produtividade e a qualidade do fruto devem ser estudados.The predominant rootstocks today in the Mediterranean basin are the citranges, especially the 'Carrizo'. The citrus tree 'Gou Tou' is considered a natural hybrid of sour orange and is one of the most common rootstocks in China. This hybrid can contribute to the diversification of the rootstocks used in Portugal and in neighboring countries. It seems to be tolerant to Tristeza disease, it grows well on calcareous soils, it is tolerant to salinity and drought. Its effect on fruit yield and quality must be studied.info:eu-repo/semantics/publishedVersio

The determinants of current ratio on Portuguese Tourism industry

Mestrado em FinançasO Turismo é uma atividade económica importante em muitos países do mundo, mas assume um papel fundamental em países de pequena dimensão como Portugal dado o impacto positivo na economia através da criação de emprego e riqueza. Este estudo pretende investigar os determinantes dos current ratio na indústria do turismo em Portugal. A análise baseou-se nos dados extraídos dos relatórios de contas anuais das empresas de turismo Portuguesas no período de 2010-2013. De modo a testar a hipótese presente neste estudo foi utilizado um modelo robusto de análise de dados em painel, no qual se usou as metodologias OLS, efeitos fixos e efeitos aleatórios. Os resultados do primeiro modelo, utilizando a metodologia de efeitos aleatórios, revelam um impacto positivo e estatisticamente significativo no current ratio por parte a rentabilidade e a idade, e negativo no caso da alavancagem financeira, tamanho da empresa, número de dias de contas a pagar e número de dias de inventário. O segundo modelo apresenta um impacto positivo da rentabilidade, idade e ciclo de conversão de liquidez, e negativo da alavancagem financeira e tamanho da empresa sobre a variável dependente. Estes resultados são consistentes com vários estudos anteriores, embora não haja provas estatisticamente significativas da relação entre o número de dias de recebimentos e o current ratio.Tourism is an important economic activity in most countries around the world but, for small countries like Portugal, it has a fundamental role due to its positive impact in the economy through the creation of jobs and wealth. This study aims to investigate the determinants of current ratio on the Portuguese tourism industry. The analysis was based on data extracted from the annual reports of the Portuguese tourism companies for the period of 2010-2013. In order to test the study hypothesis a robust panel data analysis was used, including pooled OLS, fixed effects and random effects methodologies. The results from the first model, using the random effects methodology, reveal a significant positive statistical impact on current ratio by profitability and age, and a negative by leverage, size, account payable days and inventory days. The second model presents a positive impact of profitability, age and cash conversion cycle and a negative of leverage and size on the dependent variable. These findings are consistent with several previous studies, although there is no prove of statistically significant relationship between account receivable days and current ratio

Printoo – from here to the Internet of Things

This thesis is a pedagogical case study on Strategy applied to Innovation, using Printoo – a product by Ynvisible – as a setting. Hence, the focus of this case is to describe and analyze the challenge of this company and its managers to define a fit strategy for its new, innovative product. Printoo’s concept is highly innovative and it is inserted in an area of technological development with great potential – Printed Electronics. Several tools and trends influence this area, such as the Makers culture, Crowdfunding, Open-Source and the increasing use of Technology in Education. Furthermore, there is a debate on implementing the concept of the Internet of Things – in which Printed Electronics may have a role. From the interviews and analysis performed, this paper has two key conclusions. The first one is that Ynvisible should focus on both Printoo – a series of kits of Printed Electronics technologies components – and on the company’s own proprietary Electrochromic displays – that are included in Printoo – in order to maximize the power it has over the potential profits that will derive from this innovation, because Printoo is highly imitable and the displays are not. Nevertheless, Printoo is an important marketing tool to promote Ynvisible’s displays and other components from suppliers. The second conclusion is that Education is an important market that Printoo should address, and that the approach should combine continuous improvement – of the technologies that the kits contain and of the experiences they allow to perform – and service improvement – as courses and workshops – which actually Ynvisible is starting to do. Other markets are also important, such as the Makers, Open Source market and the Prototyping market

Understanding the relevance of national culture in international business research: a quantitative analysis

This review is a comprehensive quantitative analysis of the International Business literature whose focus is on national culture. The analysis relies on a broad range of bibliometric techniques as productivity rankings, citation analysis (individual and cumulative), study of collaborative research patterns, and analysis of the knowledge base. It provides insights on (I) faculty and institutional research productivity and performance; (II) articles, institutions, and scholars’ influence in the contents of the field and its research agenda; and (III) national and international collaborative research trends. The study also explores the body of literature that has exerted the greatest impact on the researched set of selected articles.info:eu-repo/semantics/publishedVersio

Perceived image of Lisbon by foreign tourists

Mestrado em MarketingTourism destination image is one of the most approached concepts in tourism scientific literature. It has become a subject of great matter in the tourism management field once it is considered one of the most determinant factors in tourist‘s choosing process. Lisbon is currently the most important tourism destination in Portugal and one of the top visited places in Europe. According to recent data from Turismo de Portugal, in 2012 Lisbon was the first tourism destination in Portugal with the largest number of visitors, suggesting an increasing interest for the city as a tourism destination. Therefore, this work aims to contribute for a better understanding of which are the most important components of the image of Lisbon as a tourism destination for foreign tourists. After a brief literature review, we decided that this research should be based on the tri-dimensional model, developed by Echtner & Ritchie (1993), since it involves not only a tangible and functional perspective, but also a psychological and holistic one, allowing a complete representation of the perceived tourism destination image of Lisbon. The results obtained confirm a strongly positive appreciation by the international community when it comes to evaluate Lisbon’s tourism destination image, including a good evaluation of its attributes, as well as the recognition of important unique holistic elements

Looking to the future: AI in education

Artificial intelligence today rises mixed impressions amongst society. It is well-established that artificial intelligence brings advantages to different process, but these come at a cost. There is fear about the negative impacts of artificial intelligence on society. The aim of this thesis is to study acceptance about artificial intelligence in education. It investigates a group of individuals about their experience or lack of it, in learning using artificial intelligence tools, their experience and acceptance of the technology. To determine the factors that may influence the adoption of AI in education, an online survey and interviews were made online to anyone willing to answer. The questionnaire divided respondents into two different groups, people with experience and people without it. Their answers to the technology acceptance model were used to study acceptance and it was proposed social interaction as an additional factor that can influence acceptance in the education domain. The questions were analyzed by using One-Way ANOVA and multiple linear regression analysis. These conclusions point to the acceptance of both nonusers and users of AI to a mixed service, integrating traditional learning and artificial intelligence is valued by the sample acquired. It is to be expected acceptance will increase with more knowledge and social interaction. On this basis schools or learning institutions should try to implement this technology in their educational system and educate professors.A inteligência artificial hoje gera impressões diversas entre a sociedade. Está bem estabelecido que a inteligência artificial traz vantagens para diferentes processos, mas a um custo. Há medo sobre os impactos negativos da inteligência artificial na sociedade. O objetivo desta tese é estudar a aceitação da inteligência artificial na educação. Investigando um grupo de indivíduos sobre a sua experiência, ou falta dela, em usar ferramentas de inteligência artificial na aprendizagem, sua perspetiva e aceitação da tecnologia. Para determinar os fatores que podem influenciar a adoção da IA na educação, uma pesquisa online e entrevistas foram feitas online para qualquer pessoa disposta a responder. O questionário dividiu os respondentes em dois grupos diferentes, pessoas com experiência e pessoas sem experiência no uso de IA na educação. As respostas às perguntas usam uma versão do modelo de aceitação de tecnologia para estudar esta aceitação e foi proposto um fator adicional que pode influenciar a adoção no domínio da educação. As perguntas foram analisadas por meio de One-Way ANOVA e análise de regressão linear múltipla. Essas conclusões apontam para a aceitação de não usuários e usuários de IA a um serviço misto, o processo integrando da aprendizagem tradicional com a inteligência artificial é aceite pelo grupo estudado. É esperado existir um aumento da aceitação com o aumento da familiaridade e interação social. Com base nisso, as escolas ou instituições de ensino devem tentar implementar essa tecnologia em seu sistema educacional e formar professores

Total hip arthroplasty : a comparative study of the short-term results of the anterior and the lateral approach

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2018INTRODUÇÃO: A Artroplastia Total da Anca (ATA) é uma das cirurgias do aparelho locomotor mais realizadas a nível mundial, com grande impacto na qualidade de vida dos doentes e para o qual existem diferentes abordagens cirúrgicas, nomeadamente a Abordagem Anterior Direta (AAD) e pela Abordagem Lateral Direta (ALD). Cada uma destas abordagens apresenta as suas especificidades, problemas e vantagens associadas. OBJETIVOS: Este trabalho pretende estudar, compreender e descrever cirurgicamente a abordagem anterior direta e a abordagem lateral direta da ATA; comparar os resultados a curto prazo após Artroplastia Total da Anca realizada pela Abordagem Anterior Direta e pela Abordagem Lateral Direta Modificada (ALDM); identificar diferenças nos resultados funcionais obtidos, diferenças no tempo e perdas hemáticas cirúrgicos e diferenças quanto ao posicionamento dos diferentes componentes da prótese. METODOLOGIA: Este estudo é retrospetivo e os doentes selecionados foram submetidos à cirurgia pelo mesmo cirurgião no Hospital Beatriz Ângelo, que realiza a ATA segundo as duas abordagens: AAD e ALDM. Os critérios de inclusão foram: diagnóstico de coxartrose primária; eligibilidade para AAD e pelo menos 24 meses de follow up. Os critérios de exclusão foram: coxartrose secundária ou não eligibilidade para AAD segundo um dos seguintes critérios: Índice Massa Corporal (IMC) >35, altura < 155cm, coxartrose grave, coxa profunda, dysplasia ou verismo. Os doentes responderam a uma entrevista telefónica de follow up para colheita de dados clínicos e epidemiológicos. Os processos clínicos e relatos cirúrgicos foram consultados para recolha de diversos parâmetros, e a última radiografia anteroposterior da anca foi consultada para se efetuarem medições radiográficas. RESULTADOS: Foram incluídos no estudo um total de 72 doentes. 42 doentes foram operados pela AAD e 34 pela ALDM. Foram identificadas diferenças no tempo de internamento, que foi mais curto na AAD vs a ALDM, e no tempo da cirurgia, que foi mais curto no grupo da AAD do que no grupo da ALDM (p=0,003, p=0,025, respetivamente). Não encontrámos diferenças na taxa de complicações cirúrgicas (p=0,224). Em relação às medições radiográficas, a anteversão acetabular foi significativamente diferente, com a AAD sendo superior à ALDM (3,2 ± 1,23 (0,75-5,66) graus, p=0,01). No que diz respeito ao período de follow up, a duração da fisioterapia foi significativamente mais curta no grupo da AAD comparativamente ao grupo da ALDM (p=0,019) e, nem a melhoria da VAS (Visual Analogue Scale), nem o HHS (Harris Hip 8 Score) após a cirurgia, foram significativamente diferentes em ambas as abordagens (p=0,569, p=0,923, respetivamente). CONCLUSÕES: No nosso estudo, encontrámos um tempo de internamento e um tempo de cirurgia inferior no grupo da AAD. Além disso, identificámos diferenças na anteversão acetabular, com uma tendência para uma anteversão acetabular inferior com a ALDM, que associamos à noção espacial específica de cada abordagem. Não foram identificadas diferenças significativas na melhoria da VAS ou no HHS após a cirurgia, embora a duração da fisioterapia no grupo da ALDM tenha sido superior.INTRODUCTION: The Total Hip Arthroplasty (THA) is one of the most common surgical orthopaedic procedures performed all over the world and it has an enormous relevance in the treatment of severe hip osteoarthritis. This technique can be performed through several approaches, like the direct anterior and the lateral anterior approaches, two of the most used approaches worldwide. OBJETIVES: This work aims to study, comprehend and describe the Direct Anterior Approach (DAA) and the Direct Lateral Approach (DLA) of THA; to compare the short-term results after THA performed by the Direct Anterior Approach and by the Modified Direct Lateral Approach (MDLA): differences in the functional results, surgery length, blood loss and in the positioning of the prosthetic’s components. METHODS: This study followed a retrospective design, and the patients selected for this study were submitted to surgery by the same surgeon at Hospital Beatriz Ângelo, that performs the THA by the two approaches: DAA and MDLA. The inclusion criteria were a diagnosis of primary coxarthrosis, eligibility to a DAA approach and at least 24 months of follow-up. Patients were excluded if they had a secondary coxarthrosis or were not deemed eligible to a DAA approach by a combination of factors such as Body Mass Index (BMI) >35, height < 155cm, severe coxarthrosis, coxa profunda, dysplasia or varism. The patients answered a follow up telephonic interview in order to collect clinical and epidemiologic data. The patient clinical file and the surgical procedure report were consulted to assess several parameters, so as the last available anteroposterior hip radiography to perform radiographic measurements. RESULTS: A total of 72 patients were included in the study. 42 patients were operated by the DAA and 30 by the DLA approach. We found significant differences in the length of hospital stay, that was shorter in the DAA vs the MDLA group and in the length of surgery, that was shorter in the DAA group vs the MDLA group surgeries (p=0,003, p=0,025, respectively). We found no differences in the rate of surgical complications (p=0,224). About the radiographic measurements, the acetabular anteversion was significantly different, with the DAA being greater than the MDLA (3,2 ± 1,23 (0,75-5,66) degrees, p=0,01). Concerning the follow up period, the duration of physiotherapy was significantly shorter in the DAA group compared to the MDLA group (p=0,019) and 10 neither the VAS improvement nor the HHS after surgery were significantly different in both approaches (p=0,569, p=0,923, respectively). CONCLUSIONS: In our study we found a shorter length of hospital stay and length of surgery in the DAA group. We found significant differences in the acetabular anteversion, with a tendency to a lower acetabular anteversion with the MDLA, that we associate with the spatial view that each approach implies. There was no VAS improvement or HHS after surgery, although the duration of physiotherapy of the MDLA group was longer

Extractability and mobility of mercury from agricultural soils surrounding industrial and mining contaminated areas

This study focussed on a comparison of the extractability of mercury in soils with two different contamination sources (a chlor-alkali plant and mining activities) and on the evaluation of the influence of specific soil properties on the behaviour of the contaminant. The method applied here did not target the identification of individual species, but instead provided information concerning the mobility of mercury species in soil. Mercury fractions were classified as mobile, semi-mobile and non-mobile. The fractionation study revealed that in all samples mercury was mainly present in the semi-mobile phase (between 63 and 97%). The highest mercury mobility (2.7 mg kg-1) was found in soils from the industrial area. Mining soils exhibited higher percentage of non-mobile mercury, up to 35%, due to their elevated sulfur content. Results of factor analysis indicate that the presence of mercury in the mobile phase could be related to manganese and aluminum soil contents. A positive relation between mercury in the semi-mobile fraction and the aluminium content was also observed. By contrary, organic matter and sulfur contents contributed to mercury retention in the soil matrix reducing the mobility of the metal. Despite known limitations of sequential extraction procedures, the methodology applied in this study for the fractionation of mercury in contaminated soil samples provided relevant information on mercury's relative mobility