Multifunctional nanocarriers for lung drug delivery

Nanocarriers have been increasingly proposed for lung drug delivery applications. The strategy of combining the intrinsic and more general advantages of the nanostructures with specificities that improve the therapeutic outcomes of particular clinical situations is frequent. These include the surface engineering of the carriers by means of altering the material structure (i.e., chemical modifications), the addition of specific ligands so that predefined targets are reached, or even the tuning of the carrier properties to respond to specific stimuli. The devised strategies are mainly directed at three distinct areas of lung drug delivery, encompassing the delivery of proteins and protein-based materials, either for local or systemic application, the delivery of antibiotics, and the delivery of anticancer drugs-the latter two comprising local delivery approaches. This review addresses the applications of nanocarriers aimed at lung drug delivery of active biological and pharmaceutical ingredients, focusing with particular interest on nanocarriers that exhibit multifunctional properties. A final section addresses the expectations regarding the future use of nanocarriers in the area.UID/Multi/04326/2019; PD/BD/137064/2018info:eu-repo/semantics/publishedVersio

Board structure and modified audit opinions: the case of the Portuguese Stock Exchange

Prior research has found evidence that some characteristics of the board of directors influence the quality of accounting information (e.g., Beasley, 1996; Dechow et al., 1996; Klein, 2002a; Xie et al., 2003). In this study we extend the literature by analysing a different dimension of accounting information quality, the probability of a firm receiving a modified audit opinion. Using a sample of companies listed on Euronext Lisbon where firms can publish financial statements not in accordance with GAAP, unlike the current situation in other markets like the US, and 91 firm-year observations for the period 2002-03, we find evidence consistent with the hypotheses that board diligence and independence contribute negatively to the probability of a modified opinion, while board size is not statistically significant. Our results are robust to different specifications and also show that financial health, performance, growth opportunities and the existence of dividend payments are additional factors affecting the likelihood of a modified audit opinion.auditing, modified opinions, accounting quality, board structure, corporate governance, non-executive directors

Stock Splits: Real Effects or Just a Question of Maths? An Empirical Analysis of the Portuguese Case

Stock splits are conceptually a very simple corporate event that consists in the division of each share into a higher number of shares of smaller par value. These operations have long been a part of financial markets. Portugal witnessed 26 of these operations from 1999 (the year the euro was introduced) to June 2003 essentially due to a legislative change that took place when the corporate law was adapted for the introduction of the euro. In this paper stock splits are analyzed in terms of liquidity, risk, signaling and ideal price range explanations that could justify the sizeable cumulative abnormal returns (CAR) that we document around both announcement (5-day CAR of 3.8%) and ex-dates (5-day CAR of 7.5%). Our evidence shows no significant increase in trading volume (in EUR) although the number of trades does seem to increase, suggesting that trading by small investors is increased post-split. Our results also uncover an increase in the relative bid-ask spread but only for a sample subset of firms with the lowest pre- or post-split relative spreads. Our results also suggest, however, that liquidity reasons do not seem to be sufficient to explain the observed abnormal returns around the ex-date. A surprising feature is that the observed significant price increases were mainly concentrated around the ex-date, in contrast to most available evidence. The signaling hypotheses tested were not supported by the evidence presented in this study. These operations also cannot be explained by a placement of share prices levels closer to those of other Eurozone stock markets as Portuguese share prices levels are clearly much lower than the levels observable in those markets. We also conducted a survey directed at splitting firm. This confirmed that liquidity increases were indeed one of the main objectives pretended by the managers of these firms. Most companies, however, considered that this had not been accomplished. Another stated objective deemed important by managers was share capital simplification. This is puzzling since it is difficult to explain the sizeable wealth effects documented with simple changes in the par value itself. Our survey did not support signaling as a justification on the part of managers for the decision to split.Market efficiency, Stock splits, abnormal returns, trading volume,liquidity

The Impact of Programming Languages in Code Cloning

Code cloning is a duplication of source code fragments that frequently occurs in large software systems. Although different studies exist that evidence cloning benefits, several others expose its harmfulness, specifically upon inconsistent clone management. One important cause for the creation of software clones is the inherent abstraction capabilities and terseness of the programming language being used. This paper focuses on the features of two different programming languages, namely Java and Scala, and studies how different language constructs can induce or reduce code cloning. This study was further developed using our tool Kamino which provided clone detection and concrete values

ANALYSIS OF AN RGBD CAMERA FOR MANHOLE INSPECTION

As the service life of ducts and manholes reaches their end, there is a growing need to preserve the structures. In order to prevent casualties and service interruption, more frequent inspections are advised. To this day most of the inspections are still, manually made. These inspectors need to be highly qualified, and the inspections are done in an hazardous environment so, automating the inspection process would lead to a healthier workplace. Given the recent development in RGBD cameras, with smaller size factor, cost, and weight, this project aims to evaluate the application of one of the more recent models in a manhole inspection environment. Several analysis are done to assess the RGBD sensor performance for 3D model reconstruction, including the comparison with a ground-truth 3D model obtained using a laser point profile sensor with an industrial robot

An empirical study on deprivation

Mestrado em Econometria Aplicada e PrevisãoO objetivo deste trabalho é identificar os determinantes socio-económicos e demográficos da Intensidade da Privação Matéria, e investigar as suas alterações quando se considera diferentes contextos macroeconómicos - crescimento moderado versus recessão (Economia Portuguesa, anos 2004 e 2012) e os grupos complementares - Economicamente Pobres e Não-Pobres. Este trabalho usa os 9 indicadores de Privação Material presentemente usados pelo Eurostat nos 27 Estados Membros da União Europeia para modelar o Score de Privação Material. Dado que a nossa variável de interesse é uma variável de contagem, vamos aplicar métodos para modelação de dados de contagem, nomeadamente, o modelo de Poisson e o modelo Zero-Inflated Poisson. Os resultados mostram quais são os principais determinantes da Intensidade da Privação Material, e que estes não variam, de forma significativa, face aos diferentes cenários macroeconómicos e grupos considerados.The aim of this dissertation is to determine the socio-economic and demographic determinants of Material Deprivation Intensity, and investigate their changes when considering different macroeconomic backgrounds - moderate growth versus recession (Portuguese economy, years 2004 and 2012), and the additional groups - Income and Non-Income Poor. This work uses the 9 Material Deprivation indicators currently in use by Eurostat in the 27 European Union Member States to model the Material Deprivation Score. Given that the interest variable is a count variable, we will apply methodological framework for count data modeling, more particularly, Poisson and Zero-Inflated Poisson models. The results have shown what are the key determinants of the Material Deprivation Intensity, and also that they don?t change, in a significant way, in face of the considered macroeconomic backgrounds and groups

Traction and charging systems for an electric motorcycle

Dissertação de mestrado integrado em Engenharia Eletrónica Industrial e Computadores (área de especialização em Electrotecnia e Sistemas de Energia)With the current mobility paradigm, it is proven that excessive energy consumption and low energy efficiency are harming the planet and deteriorating human life conditions. Therefore it is required to substitute Internal Combustion Engines (ICEs) for electric motors and consequently shift gradually to fully electric vehicle (EV) fleets. The electrification of mobility is one of the most researched topics in all technology fields. These efforts put society closer to achieve energy sustainability and reduce the negative human impact on the environment. With this, low energy consumption vehicles such as electric motorcycles (EMs) are a very viable solution to reduce energy consumption. Due to their low power and weight, EMs have high energy efficiency and are optimized for urban transit. In this context, it becomes necessary to develop systems and prototypes common to any EV. Therefore the focus of this thesis is to implement motor traction and battery charging systems for an EM. One of the most important characteristics of an electric traction system is the possibility of applying regenerative braking. Regenerative braking converts the mechanical energy, otherwise dissipated by conventional brakes, into reusable energy that is sent back to the batteries. This process occurs due to the operation of the traction system’s power converter and improves greatly the energy efficiency of the EV. Besides, is proposed that the traction system’s input is a hand accelerator that can control the motor speed/torque. The charging system acts as an interface between the power grid and the motorcycle system. In applications such as EV charging, it is important to ensure power quality in order to maintain the developed system and the power grid healthy. With this, the first stage of the charger is AC-DC rectification and besides regulating the DC-link voltage should also act as a Power Factor Corrector (PFC) and compensate current harmonics. Secondly, the charger system should be able to regulate and control the charging process by maintaining a constant current, voltage, or temperature. The charger should also ensure the battery’s safety, and offer the possibility of regulating the charging speed. This document, details the development of traction and charger systems from the state of the art research and topologies presentation, to the computational simulations, and respective experimental tests/validation.Com o paradigma da mobilidade é evidente que o consumo excessivo de energia proveniente de combustíveis fosseis está a prejudicar o planeta. Por conseguinte, é necessário substituir os Motores de Combustão Interna (MCI) por motores eléctricos e, consequentemente, transitar gradualmente para frotas de veículos 100% elétricos (VE). A eletrificação da mobilidade é um dos tópicos com mais investimento em investigação de todos os campos tecnológicos. Estes esforços aproximam a sociedade para alcançar a sustentabilidade energética e reduzir o impacto humano no ambiente através da extração de combustíveis fósseis. Com isto, veículos de baixo consumo energético, tais como motociclos eléctricos (ME), são uma solução muito viável. Devido à sua baixa potência e peso, os MEs possuem elevada eficiência energética e são optimizados para o trânsito urbano.. Neste contexto, torna-se necessário o desenvolvimento de sistemas e protótipos comuns a qualquer EV. Portanto, o foco desta dissertação é a implementação dos sistemas de tração para um motor e de carregamento de baterias para um ME. Uma das características mais importantes de um sistema de tracção elétrica é a possibilidade de aplicar travagem regenerativa. A travagem regenerativa converte a energia mecânica, de outro modo dissipada pelos travões convencionais, em energia reutilizável que é reenviada para as baterias. Este processo ocorre devido ao funcionamento do conversor do sistema de tracção e aumenta a eficiência energética do VE. Além disso, é proposto que o sistema de tracção seja controlado através de um acelerador manual que pode controlar a velocidade/torque do motor. O sistema de carregamento actua como interface entre a rede elétrica e o motociclo. Em aplicações como o carregamento de VEs, é importante assegurar a qualidade da energia tanto do sistema desenvolvido como da rede de elétrica. Com isto, a primeira fase do carregador, para além de regular a tensão DC, deve também actuar como corrector do factor de potência (PFC). Em segundo lugar, o sistema carregador deve ser capaz de regular e controlar o processo de carregamento mantendo uma corrente, tensão ou temperatura constantes. O carregador, para além de fazer a interface entre o DC-link e a bateria, deve oferecer a possibilidade de regular a taxa de carregamento. Este documento, detalha o desenvolvimento de sistemas de tracção e carregamento desde a investigação e apresentação das topologias mais utilizadas, até às simulações computacionais, e respectivos testes experimentais/validação

Reverse left ventricular remodeling after aortic valve replacement for aortic stenosis: systematic review and meta-analysis

Introdução e objetivos: A remodelação reversa do ventrículo esquerdo (VE) após a substituição valvular aórtica (AVR), em doentes com estenose aórtica, está bem documentada como fator de prognóstico importante. No entanto, não existem valores esperados de referência. Com esta revisão sistemática e meta-análise, pretendemos caracterizar a resposta do VE após AVR. Métodos: Pesquisamos na MEDLINE/PubMed, Web of Science e Embase por estudos que relatem achados ecocardiográficos antes e pelo menos 1 mês após AVR para o tratamento de estenose aórtica. Foram identificados 5626 estudos, dos quais 4493 foram selecionados para inclusão. Os principais fatores de interesse foram as medidas estruturais e dinâmicas do VE e da válvula aórtica. Realizamos uma meta-análise de efeitos aleatórios para calcular as diferenças médias padronizadas (SMD) entre os valores de follow-up e os valores basais. Resultados: 31 estudos preencheram os critérios de elegibilidade, resultando em 2206 pacientes. AVR resultou numa redução do gradiente aórtico médio (SMD: -42.18, 95% CI: -44.39 a -39.96, I2 = 95.8%), massa do VE (para cirurgia, SMD: -84.40, CI: -103.24 a -65.57, I2 = 78.4%), massa VE indexada (SMD: -40.31, CI: -47.39 a -33.22, I2 = 78.8%), diâmetro do VE telediastólico (SMD: -2.06, CI: -3.17 a -0.94, I2 = 87.3%), volume do VE telediastólico (SMD: -13.10, CI: -18.77 a -7.43, I2 = 52.4%), espessura da parede posterior (SMD: -1.89, CI: -2.50 a -1.29, I2 = 94.1%), e espessura septal interventricular (SMD: -1.72, CI: -2.12 a -1.33, I2 = 88.1%), assim como aumento da área da válvula aórtica efetiva (SMD: 1.02, CI: 0.86 a 1.18, I2 = 96.9%) e da fração de ejeção do VE (SMD: 3.54, CI 2.22 a 4.86, I2 = 90.6%). Conclusões: A remodelação reversa ocorre após AVR e é expressa em todos os principais fatores de interesse desta revisão sistemática e meta-análise.Introduction and Objectives: Reverse Left Ventricle (LV) remodeling after Aortic Valve Replacement (AVR), in patients with aortic stenosis, is well documented as an important prognostic factor. However, there are no reference values for the expected reverse remodeling phenomenon. With this systematic review and meta-analysis, we aimed to characterize the response of the unloaded LV after AVR. Methods: We searched on MEDLINE/PubMed, Web of Science, and Embase for studies reporting echocardiographic findings before and at least 1 month after AVR for the treatment of aortic stenosis. 5626 studies were identified and 4493 were screened for inclusion. Main factors of interest were structural and dynamic measures of the LV and Aortic Valve. We performed a random-effects meta-analysis to compute standardized mean differences (SMD) between follow-up and baseline values for each outcome. Results: 31 studies met the eligibility criteria, yielding 2206 patients. AVR resulted in reduced Mean Aortic Gradient (SMD: -42.18, 95% CI: -44.39 to -39.96, I2 = 95.8%), LV Mass (for surgical AVR, SMD: -84.40, CI: -103.24 to -65.57, I2 = 78.4%), Indexed LV Mass (SMD: -40.31, CI: -47.39 to -33.22, I2 = 78.8%), End-Diastolic LV Diameter (SMD: -2.06, CI: -3.17 to -0.94, I2 = 87.3%), End-Diastolic LV Volume (SMD: -13.10, CI: -18.77 to -7.43, I2 = 52.4%), Posterior Wall Thickness (SMD: -1.89, CI: -2.50 to -1.29, I2 = 94.1%), Interventricular Septal Thickness (SMD: -1.72, CI: -2.12 to -1.33, I2 = 88.1%), and increased Effective Aortic Valve Area (SMD: 1.02, CI: 0.86 to 1.18, I2 = 96.9%), and LV Ejection Fraction (SMD: 3.54, CI 2.22 to 4.86, I2 = 90.6%). Conclusions: Reverse remodeling occurs after AVR and it is expressed in all of the main factors of interest of this systematic review and meta-analysis