Key factors influencing the performance of construction companies

In this dissertation we analyse what main factors impact the performance of companies in the construction sector. We find strong evidence that having a high equity ratio, having a large amount of its resources in cash, being able to supply credit to customers, having the government as a shareholder and having a control shareholder are factors that are positively related with performance. Besides these factors we also find that size has an ambiguous relationship with performance and that having a bank as a shareholder is, weakly, negatively related with financial performance. Furthermore, we find that the factors influencing performance on absolute terms are quite similar to the factors influencing relative performance. Our results are robust and hold, with minor differences, across the models we use.Neste estudo analisamos quais são os principais fatores que influenciam o desempenho de uma empresa de construção. Os principais fatores que encontrámos são ter um elevado rácio de capital, ter uma elevada liquidez, capacidade de conceder crédito a clientes, ter participação do estado no capital e ter um acionista maioritário. Para além destes fatores, encontrámos também que o tamanho de uma empresa tem uma relação não linear com o seu desempenho e que ter um banco como acionista está negativamente relacionado com desempenho. Os resultados obtidos, com pequenas diferenças, são consistentes nos modelos utilizados

Spectroscopic direct detection of reflected light from extra-solar planets

At optical wavelengths, an exoplanet's signature is essentially reflected light from the host star - several orders of magnitude fainter. Since it is superimposed on the star spectrum its detection has been a difficult observational challenge. However, the development of a new generation of instruments like ESPRESSO and next generation telescopes like the E-ELT put us in a privileged position to detect these planets' reflected light as we will have access to extremely high signal-to-noise ratio spectra. With this work, we propose an alternative approach for the direct detection of the reflected light of an exoplanet. We simulated observations with ESPRESSO@VLT and HIRES@E-ELT of several star+planet systems, encompassing 10h of the most favourable orbital phases. To the simulated spectra we applied the Cross Correlation Function to operate in a much higher signal-to-noise ratio domain than when compared with the spectra. The use of the Cross-Correlation Function permitted us to recover the simulated the planet signals at a level above 3 \sigma_{noise} significance on several prototypical (e.g., Neptune type planet with a 2 days orbit with the VLT at 4.4 \sigma_{noise} significance) and real planetary systems (e.g., 55 Cnc e with the E-ELT at 4.9 \sigma_{noise} significance). Even by using a more pessimistic approach to the noise level estimation, where systematics in the spectra increase the noise 2-3 times, the detection of the reflected light from large close-orbit planets is possible. We have also shown that this kind of study is currently within reach of current instruments and telescopes (e.g., 51 Peg b with the VLT at 5.2 \sigma_{noise} significance), although at the limit of their capabilities.Comment: Accepted for Publication on MNRAS: 2013 August 29; Online Article: http://mnras.oxfordjournals.org/content/early/2013/09/27/mnras.stt1642; 5 Figures, 11 page

Proposta de avaliação para a área de gerontomotricidade

O presente artigo tem como objetivo verificar qual a capacidade funcional e a composição corporal (IMC) da população idosa, alunos de uma turma de ginástica sénior antes de iniciar um programa de atividade física controlado com a duração de 10 meses. Para a realização deste estudo utilizar- se-á uma amostra formada por um grupo de 12 idosos, praticantes de ginástica Sénior, da povoação Sobral Fernando, do Concelho de Proença-a- Nova, com idades compreendidas entre os 60 e os 85 anos. Será aplicada a bateria de testes de Rikli e Jones (2001) a todos os idosos no início do programa. O tratamento dos dados obtidos, será feito através do programa estatístico Statistical Package for the Social Sciences (SPSS). Esperamos verificar com o nosso estudo, que a condição física dos participantes estará dentro dos padrões da sua idade, sendo que, depois na segunda avaliação no fim do programa, essas capacidades possam, eventualmente, manterse e melhorar.Câmara Municipal de Idanha-a-Nova, SHERU - Sport, Health & Exrecise Research Unit, Intituto Politécnico de Castelo Brancoinfo:eu-repo/semantics/publishedVersio

O programa Erasmus no IPS – vetor de internacionalização, fator de dispersão ou tão-somente um bicho-papão?

Esta comunicação pretende apresentar um conjunto de reflexões pessoais, a propósito da implementação do Programa Erasmus no IPS. A partir dos dados de mobilidade internacional na última década no Instituto, refletimos sobre a importância que o Erasmus tem assumido no IPS, em comparação com outras instituições similares. Consciente de que não há receitas únicas para o concretizar, e baseado na experiência acumulada enquanto coordenador e docente do Erasmus Course da ESGTS, apresentamos em traços largos o que tem sido o trabalho da ESGTS nesta matéria, as dificuldades que têm sido enfrentadas e os desafios que se colocam no futuro, avançando pistas sobre o que poderia ser feito para tornar o Erasmus uma realidade mais efetiva e presente nas nossas atividades

The Impact of Cognitive Fatigue on Airline Pilots Performance

Purpose: Air transport is a highly regulated branch of aviation, but it continues to show occurrences where human error is present. Fatigue is now recognized as a hazard which degrades human performance and can put flight safety at risk. In this regard, the general objective of this study is to assess the impact of cognitive fatigue on airline pilots and how it can contribute to the occurrence of accidents and incidents. Design/methodology: Three airline pilots participated in the case study. The participants’ cognitive fatigue was monitored according to four methods, being two of them of a subjective nature – the sleep diary (SD) and the Samn-Perelli 7-Point Fatigue Scale (SPS), and the other two of an objective nature – the Psychomotor Vigilance Task (PVT) and the actigraphy (actiwatch ReadibandTM 5). During their flight duty periods (FDPs), the pilots’ performance was also assessed according to the score delivered by a fatigue management software (FAID®). Findings: The obtained results allowed to understand whether the pilots are aware of their alertness and to identify factors which affect their performance levels. Between the beginning and the end of each FDP, significant changes were observed concerning the assessment on the SPS scale, the reaction time (RT) and the fatigue score generated by the biomathematical models associated to the technique of the actigraphy and the software FAID®. Originality/value: The risk of accident or serious error was classified according to the four methodologies used. Thus, it is possible to verify if there is a correspondence between the different scales or if there are scales more conservative (with a higher associated risk) than others.Peer Reviewe

Silting modules and ring epimorphisms

There are well-known constructions relating ring epimorphisms and tilting modules. The new notion of silting module provides a wider framework for studying this interplay. To every partial silting module we associate a ring epimorphism which we describe explicitly as an idempotent quotient of the endomorphism ring of the Bongartz completion. For hereditary rings, this assignment is used to parametrise homological ring epimorphisms by silting modules. We further show that homological ring epimorphisms of a hereditary ring form a lattice which completes the poset of noncrossing partitions in the case of finite dimensional algebras

Noise-induced gastric lesions : a light and electron microscopy study of the rat gastric wall exposed to low frequency noise

"Context - Only a few studies evaluated the digestive alterations caused by low frequency noise (LFN) and most focused only on mucosal alterations. Objectives - To investigate the morphological injury of LFN-exposed gastric wall, beyond the epithelial layer. Methods - Wistar rats were exposed to low frequency noise (LFN), during increasing periods, 1 to 13 weeks. A control group was kept in silence. Gastric specimens were studied using: (i) light microscopy with hematoxylin-eosin and immunostaining for collagens; (ii) transmission electron microscopy; (iii) morphometry allowing statistical analysis. Results - Submucosa of all LFN-exposed animals exhibit increased thickness with fibrous proliferation. Transmission electron microscopy showed massive collagen deposition. Immunostaining identified collagen IV as responsible for the increased thickness. Morphometry allowed the demonstration of a significant difference of thickness between control and exposed groups. Vascular alterations included: i) intima proliferation and thickening, rupture of the internal elastic lamina, thrombotic changes; ii) thickening of the media; iii) after 9 weeks of LFN-exposure, we found new formed vessel presenting tortuous and twisted. There is a significant difference of arterial wall thickness between control and exposed groups. Conclusions - Deeper layers of gastric wall undergo alterations, including fibrosis of the submucosa caused by collagen IV deposition, an early marker of neoangiogenesis. Vascular alterations included thickening and thrombotic phenomena, but also images of newly formed vessels. This study suggests that, at least in the stomach, LFN-induced fibrosis could be linked with neoangiogenesis.