Do founder-CEO firms outperform the market?

Estudos recentes relatam diferenças na performance de empresas com base no status do respetivo CEO. Este estudo examina empiricamente o desempenho das empresas cujo CEO é fundador. Utilizo uma amostra de 96 empresas americanas públicas cujo CEO é fundador ou cofundador para estimar os coeficientes das variáveis explicativas de Fama e French (1992) SMB, HML, WML, RMW e CMA usando o estimador de mínimos quadrados. Os resultados obtidos são emocionantes e esclarecedores. Ambas os portfólios produzem resultados robustos e com significância estatística global. Os portfólios value-weighted e eqaual-weighted obtêm retornos que variam de 1.51% a 2.01%. Isto sugere que existe um nexo de causalidade entre a existência de retornos anormais positivos e a performance de empresas cujo CEO é fundador e é de grande importância para os profissionais que trabalham no setor financeiro.Research has been conducted that finds differences in firm performance according to the CEO status. This dissertation empirically examines founder-CEO firm’s performance. I use a sample of 96 listed US companies that are either founder or co-founder run to regress Fama and French’s (1992) independent variables SMB, HML, WML, RMW and CMA on equal-weighted and value-weighted excess returns using the OLS regression model. The results obtained are exciting and clarifying. Both portfolios produce very robust results and global statistical significance throughout. I find that the value-weighted and equal-weighted portfolios earn abnormal monthly returns ranging from 1.51% to 2.01%. This finding suggests there is a causal link between the existence of positive abnormal returns and founder-CEO firms and is of high importance for practitioners working in the finance industry

PfMDR1: Mechanisms of Transport Modulation by Functional Polymorphisms

ATP-Binding Cassette (ABC) transporters are efflux pumps frequently associated with multidrug resistance in many biological systems, including malaria. Antimalarial drug-resistance involves an ABC transporter, PfMDR1, a homologue of P-glycoprotein in humans. Twenty years of research have shown that several single nucleotide polymorphisms in pfmdr1 modulate in vivo and/or in vitro drug susceptibility. The underlying physiological mechanism of the effect of these mutations remains unclear. Here we develop structural models for PfMDR1 in different predicted conformations, enabling the study of transporter motion. Such analysis of functional polymorphisms allows determination of their potential role in transport and resistance. The bacterial MsbA ABC pump is a PfMDR1 homologue. MsbA crystals in different conformations were used to create PfMDR1 models with Modeller software. Sequences were aligned with ClustalW and analysed by Ali2D revealing a high level of secondary structure conservation. To validate a potential drug binding pocket we performed antimalarial docking simulations. Using aminoquinoline as probe drugs in PfMDR1 mutated parasites we evaluated the physiology underlying the mechanisms of resistance mediated by PfMDR1 polymorphisms. We focused on the analysis of well known functional polymorphisms in PfMDR1 amino acid residues 86, 184, 1034, 1042 and 1246. Our structural analysis suggested the existence of two different biophysical mechanisms of PfMDR1 drug resistance modulation. Polymorphisms in residues 86/184/1246 act by internal allosteric modulation and residues 1034 and 1042 interact directly in a drug pocket. Parasites containing mutated PfMDR1 variants had a significant altered aminoquinoline susceptibility that appears to be dependent on the aminoquinoline lipophobicity characteristics as well as vacuolar efflux by PfCRT. We previously described the in vivo selection of PfMDR1 polymorphisms under antimalarial drug pressure. Now, together with recent PfMDR1 functional reports, we contribute to the understanding of the specific structural role of these polymorphisms in parasite antimalarial drug response

Análise e dimensionamento de uma estrutura de cobertura em membrana tensa

Tese de mestrado integrado. Engenharia Civil (Estruturas). Universidade do Porto. Faculdade de Engenharia. 201

Segtor: Rapid Annotation of Genomic Coordinates and Single Nucleotide Variations Using Segment Trees

Various research projects often involve determining the relative position of genomic coordinates, intervals, single nucleotide variations (SNVs), insertions, deletions and translocations with respect to genes and their potential impact on protein translation. Due to the tremendous increase in throughput brought by the use of next-generation sequencing, investigators are routinely faced with the need to annotate very large datasets. We present Segtor, a tool to annotate large sets of genomic coordinates, intervals, SNVs, indels and translocations. Our tool uses segment trees built using the start and end coordinates of the genomic features the user wishes to use instead of storing them in a database management system. The software also produces annotation statistics to allow users to visualize how many coordinates were found within various portions of genes. Our system currently can be made to work with any species available on the UCSC Genome Browser. Segtor is a suitable tool for groups, especially those with limited access to programmers or with interest to analyze large amounts of individual genomes, who wish to determine the relative position of very large sets of mapped reads and subsequently annotate observed mutations between the reads and the reference. Segtor (http://lbbc.inca.gov.br/segtor/) is an open-source tool that can be freely downloaded for non-profit use. We also provide a web interface for testing purposes

Motion control of mobile autonomous robots using non-linear dynamical systems approach

This paper presents a solution to the problem of motion control of an autonomous robot, moving in a dynamical and unstable environment. It is based on non-linear dynamical systems, modelling the state variables that define the motion of a robot under an omnidirectional platform, like its direction of navigation and velocity. The approach used, is based on a set of non-linear differential equations that model the evolution of state variables along time, based on the concept of attractors and repellers. In the official RoboCup Middle Size League field, a target is used to attract the robot to a certain position (could be the ball or a desired position to receive the ball), while a repeller could move the robot away from its original path (given by obstacles in the surrounding environment). The research was firstly carried out in a computational simulation environment and later on with robots in a real environmentThis work was developed at the Automation and Robotics Laboratory by MINHO R&D TEAM, University of Minho, under the supervision of Professor A. Fernando Ribeiro and A. Gil Lopes. The knowledge exchanging between the RoboCup’s MSL teams and community contributed greatly for the development of this work. This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013.info:eu-repo/semantics/publishedVersio

A terapêutica antitrombótica: atual e em desenvolvimento

ResumoA trombose é uma das principais causas de morte e o crescente conhecimento das alterações fisiopatológicas inerentes permitiu o desenvolvimento de terapêuticas eficazes (antiagregante, anticoagulante e fibrinolítico) para a prevenção e tratamentos da doença tromboembólica.Contudo, uma compreensão melhor do processo subjacente é fundamental para o desenvolvimento de novos agentes terapêuticos mais seguros e eficazes.O objetivo da presente revisão é sumarizar os tratamentos atuais disponíveis, e destacar os novos agentes e o seu papel comprovado ou eventual na cirurgia vascular.AbstractThrombosis is one of the major causes of death worldwide. Continous increase in the knowledge about the pathophysiological changes associated with thrombosis led to the development of effective therapies (anti‐platelet, anticoagulant and fibrinolytics) for the prevention and treatment of the thromboembolic disease.However, better understanding of the underlying processes is still crucial for the development of more effective and safer antithrombotic drugs.The aim of this review is summarize the current treatment, as well as the new agentes and to highlight their proven or possible role in Vascular Surgery

An update on pharmacogenetic factors influencing the metabolism and toxicity of artemisinin-based combination therapy in the treatment of malaria

Funding Information: This paper was funded by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil) (404067/2012-3 and 2020/00433-8), the European and Developing Countries Clinical Trials Partnership (EDCTP) (RIA2017T-2018), the Fundação de Amparo *a Pesquisa do Estado de mInas Gerais (FAPEMIG) (CBB-APQ 00952-16) and the Fundação para a Ciência e Tecnologia (FCT, Portugal) (SFRH/BD/142860/2018). Funding Information: L Pernaute-Lau is a recipient of a fellowship from BioSys PhD program PD65‐2012 (Ref SFRH/BD/142860/2018) from Fundação para a Ciência e Tecnologia (FCT, Portugal). JP Gil, M Camara and U Morris were partially supported by the European Developing Countries Clinical Trial Partnership (EDCTP2) programme supported by the European Union (Grant number RIA2017T-2018 – WANECAM 2). T Nóbrega de Sousa is a recipient of a Senior Research Scholarships from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil). Funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPqants number 404,067/2012-3, 2020/00433-8), and the Fundação de Amparo à Pesquisa do Estado de mInas Gerais (FAPEMIG), grant number CBB-APQ 00952-16). MU Ferreira was funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPqants number 404,067/2012-3, 2020/00433-8), and the Fundação de Amparo à Pesquisa do Estado de mInas Gerais (FAPEMIG), grant number CBB-APQ 00952-16). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Publisher Copyright: © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Introduction: Artemisinin-based combination therapies (ACTs) are recommended first-line antimalarials for uncomplicated Plasmodium falciparum malaria. Pharmacokinetic/pharmacodynamic variation associated with ACT drugs and their effect is documented. It is accepted to an extent that inter-individual variation is genetically driven, and should be explored for optimized antimalarial use. Areas covered: We provide an update on the pharmacogenetics of ACT antimalarial disposition. Beyond presently used antimalarials, we also refer to information available for the most notable next-generation drugs under development. The bibliographic approach was based on multiple Boolean searches on PubMed covering all recent publications since our previous review. Expert opinion: The last 10 years have witnessed an increase in our knowledge of ACT pharmacogenetics, including the first clear examples of its contribution as an exacerbating factor for drug–drug interactions. This knowledge gap is still large and is likely to widen as a new wave of antimalarial drug is looming, with few studies addressing their pharmacogenetics. Clinically useful pharmacogenetic markers are still not available, in particular, from an individual precision medicine perspective. A better understanding of the genetic makeup of target populations can be valuable for aiding decisions on mass drug administration implementation concerning region-specific antimalarial drug and dosage options.publishersversionpublishe

Gadolinium ecotoxicity is enhanced in a warmer and acidified changing ocean as shown by the surf clam Spisula solida through a multibiomarker approach

Funding Information: This work was supported by Fundação para a Ciência e Tecnologia (FCT) , through the project Climatoxeel ( PTDC/AAG-GLO/3795/2014 ), by the Junior Researcher contract ( CEECIND/03517/2017 ), both awarded to Tiago F. Grilo, and the strategic project UIDB/04292/2020 granted to MARE and through project LA/P/0069/2020 granted to the Associate Laboratory ARNET . The work was also supported by the European Union's operation program Mar 2020 through the research project CEIC ( MAR-01.04.02-FEAMP-0012 ) awarded to Joana Raimundo. The Applied Molecular Biosciences Unit UCIBIO was financed by national funds from FCT ( UIDP/04378/2020 ). This work was also supported by the European Union through the grant ERC-2016-COG-725034 -ecotox awarded to Inês João Ferreira. Cátia Figueiredo acknowledges the FCT-PhD grant SFRH/BD/130023/2017 and the Early Career Research Grant awarded by National Geographic Society. Publisher Copyright: © 2022 The Author(s)Humans have exhaustively combusted fossil fuels, and released pollutants into the environment, at continuously faster rates resulting in global average temperature increase and seawater pH decrease. Climate change is forecasted to exacerbate the effects of pollutants such as the emergent rare earth elements. Therefore, the objective of this study was to assess the combined effects of rising temperature (Δ = + 4 °C) and decreasing pH (Δ = − 0.4 pH units) on the bioaccumulation and elimination of gadolinium (Gd) in the bioindicator bivalve species Spisula solida (Surf clam). We exposed surf clams to 10 µg L−1 of GdCl3 for seven days, under warming, acidification, and their combination, followed by a depuration phase lasting for another 7 days and investigated the Gd bioaccumulation and oxidative stress-related responses after 1, 3 and 7 days of exposure and the elimination phase. Gadolinium accumulated after just one day with values reaching the highest after 7 days. Gadolinium was not eliminated after 7 days, and elimination is further hampered under climate change scenarios. Warming and acidification, and their interaction did not significantly impact Gd concentration. However, there was a significant interaction on clam's biochemical response. The augmented total antioxidant capacity and lipid peroxidation values show that the significant impacts of Gd on the oxidative stress response are enhanced under warming while the increased superoxide dismutase and catalase values demonstrate the combined impact of Gd, warming & acidification. Ultimately, lipid damage was greater in clams exposed to warming & Gd, which emphasizes the enhanced toxic effects of Gd in a changing ocean.publishersversionpublishe

Ocean warming, acidification, and rare earth elements exposure triggers a superior antioxidant response and pigment production in the adaptable Ulva rigida

European Union's operation program Mar 2020 through the research project CEIC (MAR-01.04.02-FEAMP-0012). Inês João Ferreira acknowledges the European Union research grant ERC-2016-COG-725034-ecotox. Publisher Copyright: © 2022 The Author(s)Anthropogenic increased atmospheric CO2 concentrations will lead to a drop of 0.4 units of seawater pH and ocean warming up to 4.8°C by 2100. Contaminant's toxicity is known to increase under a climate change scenario. Rare earth elements (REE) are emerging contaminants, that until now have no regulation regarding maximum concentration and discharge into the environment and have become vital to new technologies such as electric and hybrid-electric vehicle batteries, wind turbine generators and low-energy lighting. Studies of REE, namely Lanthanum (La) and Gadolinium (Gd), bioaccumulation, elimination, and toxicity in a multi-stressor environment (e.g., warming and acidification) are lacking. Hence, we investigated the algae phytoremediation capacity, the ecotoxicological responses and total chlorophyll and carotenoid contents in Ulva rigida during 7 days of co-exposure to La or Gd (15 µg L−1 or 10 µg L−1, respectively), and warming and acidification. Additionally, we assessed these metals elimination, after a 7-day phase. After one day of experiment La and Gd clearly showed accumulation/adsorption in different patterns, at future conditions. Unlikely for Gd, Warming and Acidification contributed to the lowest La accumulation, and increased elimination. Lanthanum and Gd triggered an adequate activation of the antioxidant defence system, by avoiding lipid damage. Nevertheless, REE exposure in a near-future scenario triggered an overproduction of ROS that requested an enhanced antioxidant response. Additionally, an increase in total chlorophyll and carotenoids could also indicate an unforeseen energy expense, as a response to a multi-stressor environment.publishersversionpublishe