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- Bridges Between Bipolar and Borderline Personality Disorders: Clarifying Comorbidity Through the Analysis of the Complex Network of Connections Between SymptomsPublication . Castro, Daniel; Ferreira, Filipa; Mendes, Ana Sofia; Ferreira, Tiago BentoThe reasons for the high rates of comorbidity between Bipolar (BD) and Borderline Personality (BPD) disorders remain elusive, due to the vast array of shared clinical features, which makes the differential diagnosis difficult. This constitutes an obstacle to provide quality of care services, which results in detrimental effects on individual’s mental health. The analysis of the complex network of connections between symptoms of both disorders is a promising pathway to uncover the mechanisms underlying the comorbidity structure of both disorders
- O Esporte e a NutriçãoPublication . Ferreira, Alan de Carvalho DiasA importância da nutrição no desempenho e saúde de atletas já se encontra suficientemente documentada na literatura, contudo pouco interesse é destinado à investigação das razões que levam às escolhas alimentares desses indivíduos. Sendo assim, o objetivo deste artigo é descrever a relação atual entre o esporte e a nutrição, assim como discutir a prática alimentar de atletas de diferentes modalidades esportivas frente às referências nutricionais. Os estudos têm reafirmado a necessidade da reeducação nutricional em diferentes grupos de atletas. Contudo, a percepção prática tem alertado para a compreensão de que o satisfatório atendimento das demandas nutricionais de atletas requer a elaboração de um cuidadoso planejamento alimentar, que inclua manipulações dietéticas adaptadas à sua modalidade esportiva e estilo de vida.
- Key determinants of time to 5 m in different ventral swimming start techniquesPublication . Peterson Silveira, Ricardo; Stergiou, Pro; Figueiredo, Pedro; Castro, Flávio de S.; Katz, Larry; Stefanyshyn, Darren J.The aim of this study was to determine the biomechanical parameters that explain ventral start performance in swimming. For this purpose, 13 elite swimmers performed different variants of the ventral start technique. Two-dimensional video analyses of the aerial and underwater phases were used to assess 16 kinematic parameters from the starting signal to 5 m, and an instrumented starting block was used to assess kinetic data. A Lasso regression was used to reduce the number of parameters, providing the main determinants to starting performance, revealing different combinations of key determinants, depending on the variant (r² ≥ 0.90), with flight distance being the most relevant to all variants (r ≤ -0.80; p < .001). Also, special attention should be given to the total horizontal impulse in the grab start (r = -0.79; p < .001) and to the back foot action in the track and kick starts (r ≤ 0.61; p < .001). In addition, we provide two equations that could be easily used to predict starting performance by assessing block time and flight time (r² = 0.66) or block time and flight distance (r² = 0.83). These data provide relevant contributions to the further understanding of the biomechanics of swimming starts as well as insights for performance analysis and targeted interventions to improve athlete performance.
- Determinants of credit default swaps implied ratings during the crisis: was sovereign risk mispriced?Publication . Alberta Oliveira, Maria; Santos, CarlosThis paper addresses the question of whether sovereign risk pricing was related to macroeconomic fundamentals, between 2007 and 2015, in a sample of OECD countries. The authors argue that the conflicting evidence in the literature is due to poor methodology options. The researchers innovate by modelling sovereign credit default swaps implied ratings as our sovereign risk proxy, instead of spreads, avoiding common pitfalls. Furthermore, the authors improve the variable selection, model specification and the econometric procedures used. A panel ordered probit model is chosen, assuring robust inference. The authors relax the parallel lines assumption, allowing for rating-varying coefficients of explanatory variables. The result is the first congruent model of sovereign risk during the years of the financial crisis and of the Euro Area crisis. Fiscal space variables, economic activity indicators, variables pertaining to external imbalances, and contagion proxies are relevant, with effects matching theory priors. The scientists clarify conundrums in the previous literature, posed by lack of significance of some macro fundamentals and by puzzling signs of some estimated coefficients. Moreover, this is the first paper to estimate not only the global risk premium, but also the impact of changing risk aversion. The authors find no support for claims of sovereign risk mispricing during the sample period. The results allow relevant policy conclusions, namely concerning the validity of different fiscal consolidation paths in financially distressed countries.
- Augmented Reality Trends to the Field of Business and Economics: A Review of 20 years of ResearchPublication . Roxo, Mafalda Teles; Brito, Pedro QuelhasAugmented Reality (AR) is emerging as a technology that is reshaping the current society, especially the fields of Business and Economics (B&E). Therefore, the scientific studies produced on AR call for an interdisciplinary systematic review of the knowledge generated to structure an organized framework. Three main questions are addressed: How has the production of AR scientific knowledge evolved? What user-related aspects does AR affect? Also, which set of subtopics is associated with each motivation to develop an AR solution? The content of 328 papers produced between 1997 and 2016 in the field of AR is analyzed, unveiling 58 coding categories. There are 13 digital media characteristics that assume instrumental roles in addressing four major motivations to develop AR solutions. Technological topics dominate the research focus over behavioral ones. The investigations on AR in mobile displays show the highest increase. This research identifies the main scientific topics that have led researchers' agenda. Consequently, they contributed to develop and to adopt AR solutions and to forecast its future application in the organizations' strategies
- Associations of Quadriceps Torque Properties with Muscle Size, Attenuation, and Intramuscular Adipose Tissue in Older AdultsPublication . Frank-Wilson, Andrew W; Chalhoub, Didier; Figueiredo, Pedro; Jónsson, Pálmi V; Siggeirsdóttir, Kristín; Sigurdsson, Sigurdur; Eiriksdottir, Gudny; Guðnason, Vilmundur; Launer, Lenore; Harris, Tamara BAtrophy and fatty infiltration of muscle with aging are associated with fractures and falls, however, their direct associations with muscle function are not well described. It was hypothesized that participants with lower quadriceps muscle attenuation, area, and greater intramuscular adipose tissue (IMAT) will exhibit slower rates of torque development (RTD) and lower peak knee extension torques.
- Association Between Perceived and Actual Motor Competence in Portuguese ChildrenPublication . Lopes, Vítor Pires; Saraiva, Linda; Gonçalves, Celina; Rodrigues, Luis P.The aim of this study was to examine the relationship between actual (AMC) and perceived (PMC) motor competence in Portuguese children. A total of 200 children (111 [0.55%] girls) aged 5–9 years old participated in the study. The Pictorial Scale of Perceived Movement Skill Competence (PMSC) and the Test of Gross Motor Development-2 (TGMD2) were used to assess PMC and AMC, respectively. Mann-Whiney U was used to test the differences between sexes and age groups. The association between TGMD2 and PMSC scores was analyzed through Spearman correlation. Boys and girls of all ages showed to have high PMC. Independent of sex, mean values for each TGMD2 subtest increased throughout the age groups with older children having significantly higher mean scores than younger ones. In general, boys and girls showed similar PMC and AMC, independent of age. Weak to moderate and some negative correlations (0.24 < r < −0.40) were found between PMC and AMC scores for all age and sex groups. In conclusion, there appears to be little relationship between actual and perceived motor competence in Portuguese young children.
- Compreender a retenção de membros em centros de fitness: Um estudo em áreas urbanas de PortugalPublication . Gonçalves, CelinaTem-se como objetivo compreender a retenção de membros e como esta é influenciada em clubes de fitness de áreas urbanas em Portugal. A retenção de clientes é crucial no fitness devido ao seu impacto na rentabilidade das organizações. Por esse motivo, vários estudos tentam compreender e explicar seus antecedentes. A metodologia baseou-se na revisão bibliográfica, incluiu artigos sobre retenção de fitness em Portugal, publicados entre 2012 e 2017 e revistos por pares. A pesquisa foi realizada nas bases de dados B-on e repositórios universitários. A análise incluiu o exame de títulos e palavras-chave das publicações, considerando os termos relacionados à retenção de clientes. The results refer to one of the largest Portuguese fitness networks. Os antecedentes que influenciam a retenção dos membros em centros de fitness em Portugal são a qualidade do serviço, os resultados indicam que a percepção de alguns atributos influencia a retenção (e.g. instalações e equipamentos).
- Toward a Resource-Based View of City Quality: A New FrameworkPublication . Carvalho, João M. S.; Costa, Ricardo V.; Marnoto, Sandra; Sousa, Célio A. A.; Vieira, José Carvalho
- High-intensity Interval Training in Different Exercise Modes: Lessons from Time to ExhaustionPublication . Sousa, Ana; Fernandes, Ricardo; Boas, Joao; Figueiredo, PedroTo provide information for high-intensity interval training (HIIT) load, we compared the temporal variables of VO2 response at, and after, a time sustained at the exercise intensity corresponding to VO2max (Tlim) in different exercise modes. Forty-five trained male swimmers (11), rowers (13), runners (10) and cyclists (11) completed an incremental protocol to determine the velocity (vVO2max) or power (wVO2max) at VO2max and a square wave exercise from rest to 100% of vVO2max/wVO2max. The temporal variables of VO2 response were examined using a breath-by-breath gas analyzer. VO2 responses were not different between exercise modes, except for the percentage of VO2max at 50% of Tlim, which was ~6% higher in rowing compared to cycling (97.70±2.90 vs 92.40±5.69%, p=0.013). During the recovery period, both swimmers and rowers evidenced higher percentages of VO2max compared to cyclists at 30 s (65.1±10.4 and 65.7±5.6 vs 52.7±5.6%) and 60 s (41.7±10.8 and 38.4±5.4 vs 30.4±1.8%) time periods, all for p<0.01. Furthermore, swimmers presented higher time values to reach 50% VO2max compared to runners and cyclists (51.1±15.6 vs 38.1±6.7 and 33.8±4.7%; p<0.001). When training at 100% of VO2max intensity, fixed intervals for HIIT could be set freely. However, recovery periods based on time or intensity are exercise-mode dependent.