The compact group--fossil group connection: observations of a massive compact group at z=0.22

It has been suggested that fossil groups could be the cannibalized remains of compact groups, that lost energy through tidal friction. However, in the nearby universe, compact groups which are close to the merging phase and display a wealth of interacting features (such as HCG 31 and HCG 79) have very low velocity dispersions and poor neighborhoods, unlike the massive, cluster-like fossil groups studied to date. In fact, known z=0 compact groups are very seldom embedded in massive enough structures which may have resembled the intergalactic medium of fossil groups. In this paper we study the dynamical properties of CG6, a massive compact group at z=0.220 that has several properties in common with known fossil groups. We report on new g' and i' imaging and multi-slit spectroscopic performed with GMOS on Gemini South. The system has 20 members, within a radius of 1 h_70^-1 Mpc, a velocity dispersion of 700 km/s and has a mass of 1.8 x 10^14 h_70^-1 Msun, similar to that of the most massive fossil groups known. The merging of the four central galaxies in this group would form a galaxy with magnitude M_r' ~ -23.4, typical for first-ranked galaxies of fossil groups. Although nearby compact groups with similar properties to CG 6 are rare, we speculate that such systems occurred more frequently in the past and they may have been the precursors of fossil groups.Comment: 7 pages, 3 figures (one color, low resolution), uses emulateapj.sty. Accepted for publication in ApJ Lette

Mass Distribution in Hickson Compact Groups of Galaxies

This study presents the mass distribution for a sample of 18 late-type galaxies in nine Hickson Compact Groups. We used rotation curves from high resolution 2D velocity fields of Fabry-Perot observations and J-band photometry from the 2MASS survey, in order to determine the dark halo and the visible matter distributions. The study compares two halo density profile, an isothermal core-like distribution and a cuspy one. We also compare their visible and dark matter distributions with those of galaxies belonging to cluster and field galaxies coming from two samples: 40 cluster galaxies of Barnes et al (2004) and 35 field galaxies of Spano et al. (2008). The central halo surface density is found to be constant with respect to the total absolute magnitude similar to what is found for the isolated galaxies. This suggests that the halo density is independent to galaxy type and environment. We have found that core-like density profiles fit better the rotation curves than cuspy-like ones. No major differences have been found between field, cluster and compact group galaxies with respect to their dark halo density profiles.Comment: 35 pages, 21 figures. Accept for publication in Astronomical Journa

Isometric mid-thigh pull testing in professional footballers: validity, reliability, and correlation analysis with external loading during official matches

INTRODUCTION: Understanding the maximum strength of football players is considered essential for optimizing and maintaining individuals for high level sports performance. In this regard, the mid-thigh isometric traction test (IMTP) has been proposed to assess the overall maximum strength of football players. OBJECTIVES: This thesis aimed to achieve four objectives, the first being: 1) examine the concurrent validity between two modalities of IMPT testing equipment in healthy individuals: i) with a force platform at the foot; and ii) with a force cell next to the handle bar. The second being: 2) determine if there is a learning period in taking the IMTP test between the first four testing sessions among professional footballers, examining the inter-session reliability between the first two similar sessions. The third being: 3) to verify whether the IMPT peak force is altered following football matches; and, lastly: 4) examine whether the changes in IMPT peak force 48h following matches is related with different external loading parameters experienced by the players during the match. METHODS: For objective 1, one experimental session was conducted with healthy individuals (n=24); and for the remaining objectives, a total of 40 footballers from a professional football team were recruited, and who participated in IMPT testing sessions. External loading parameters were quantified during the matches using a GPS tracking system worn by the footballers. RESULTS: 1) A low concurrent validity was observed between the IMPT testing equipment assessments [ICC = 0.47 (95% CI = -0.21- 0.79), CV = 10.8% (95% CI = 6.88 – 14.8%)]; whereas, a lower IMTP peak force was observed for the testing executed with the force platform (1693.9±112.5 N) compared with the force load cell test (1880.3±156.5 N, p<0.001). 2) Significant differences were found between the first (1843.6± 333.7 N), and second (2008.1± 397.4 N, p= 0.002), the first and third (2143.6± 454.8 N, p<0.001), and the first and fourth (2226.9±442.2 N, p < 0.001) IMTP testing sessions. No significant differences were found between the second and third sessions (p=0.085), and the third and fourth sessions (p= 1.000). Good inter-session reliability was observed between the second and third testing sessions (ICC = 0.84, standard error of measurement of 218.1± 308.4 N). 3) No statistically significant differences were found in both samples (p = 0.744 and p = 0.520). 4) A moderate and negative correlation was found between the IMTP peak force before matches and the footballer’s frequency of “accelerations” (r= -0.501 and p=0.048), and a positive correlation was observed between the IMPT peak force before and after matches (r= 0.738 and p<0.001). No other significant correlations were found. CONCLUSIONS: 1) The IMTP peak force outcome depends on the equipment used, with higher IMTP values obtained using a load cell close to the hands; 2) At least two separate familiarization sessions are necessary for professional footballers to achieve a reliable IMPT assessment; 3) The IMTP performance is unlikely to be altered 48h after football matches compared to the IMPT performance 48h before the matches; and 4) The IMTP assessments before and after the matches do not seem to be correlated with the different external loading parameters exerted by footballers during official matches.INTRODUÇÃO: Compreender a força máxima em jogadores de futebol é essencial para otimizar e manter o desempenho desportivo individual. Nesse sentido, o teste isometric mid-thigh pull (IMTP) foi proposto para avaliar a força máxima geral nos jogadores de futebol. OBJETIVOS: Esta tese visa atingir quatro objetivos, sendo o primeiro: 1) examinar a validade concorrente entre duas modalidades de equipamentos de teste IMTP em indivíduos saudáveis: i) com uma plataforma de força nos pés; e ii) com uma célula de força próxima das mãos. O segundo é: 2) determinar se há um período de aprendizagem na realização do teste IMTP entre as quatro primeiras sessões para jogadores profissionais de futebol, examinando a confiabilidade inter sessões nas duas primeiras sessões. O terceiro: 3) verificar se o pico de força do IMTP é alterado após os jogos de futebol; e, por último: 4) examinar se as mudanças no pico de força no IMTP 48h após os jogos estão relacionadas com diferentes parâmetros de carga externa obtidos pelos jogadores durante o jogo. MÉTODOS: Para o objetivo 1, foi realizada uma sessão experimental com indivíduos saudáveis (n=24); e para os restantes objetivos foram recrutados um total de 40 futebolistas de uma equipa de futebol profissional, que participaram em sessões de testes no IMTP. Parâmetros de carga externa foram quantificados durante os jogos utilizando um sistema de GPS usado pelos jogadores. RESULTADOS: 1) Observou-se baixa validade concorrente entre as avaliações no equipamento IMTP [ICC = 0,47 (IC 95% = -0,21- 0,79), CV = 10,8% (IC 95% = 6,88 – 14,8%)]; também se observou um menor pico de força IMTP para o teste executado com a plataforma de força (1693,9±112,5 N) em comparação com o teste da célula de carga de força (1880,3±156,5 N, p<0,001). 2) Foram encontradas diferenças significativas entre a 1ª (1843,6± 333,7 N) e a 2ª (2008,1± 397,4 N, p= 0,002), e entre a 1ª e 3ª (2143,6± 454,8 N, p<0,001) e entre a 1ª e 4ª (2226,9±442,2 N, p < 0,001) sessões de teste no IMTP, mas não entre a 2ª e 3ª sessões (p=0,085), e a 3ª e 4ª sessões (p= 1,000). Boa confiabilidade inter sessões foi observada entre a 2ª e 3ª sessões de teste (ICC = 0,84, erro padrão de medição de 218,1± 308,4 N). 3) Não foram encontradas diferenças estatisticamente significativas em ambas as amostras (p = 0,744 e p = 0,520). 4) Observou-se uma correlação moderada e negativa entre o pico de força do IMTP antes dos jogos e a frequência de “acelerações” dos futebolistas (r= -0,501 e p=0,048), e uma correlação positiva foi observada entre o pico de força no IMTP antes e depois dos jogos (r= 0,738 e p<0,001). Não foram encontradas outras correlações significativas. CONCLUSÕES: 1) O resultado do pico de força no IMTP depende do equipamento utilizado, com maiores valores de IMTP obtidos utilizando uma célula de carga próxima às mãos; 2) Pelo menos duas sessões separadas de familiarização são necessárias para que os jogadores de futebol profissional alcancem uma avaliação confiável do IMTP; 3) O desempenho dos jogadores no teste IMTP parece não sofrer alterações 48h antes e depois dos jogos de futebol; e 4) As avaliações no IMTP antes e depois dos jogos não parecem estar correlacionadas com os diferentes parâmetros de carga externa obtidos pelos futebolistas durante os jogos

The effect of social media and celebrities on Millennials’ Consumers : the Pantene example

The present dissertation provides an overview of significant marketing related topics such as digital branding, digital marketing, targeting, positioning, social media as a marketing tool and the effectiveness of celebrity endorsers’ campaigns. These topics are discussed and analysed in a case study focused on the haircare industry, where Pantene takes the centre stage. The case study introduces this extremely competitive industry, whose dynamics have been shifting due to the price sensitivity of the average consumer. Additionally, consumers spend, nowadays, most of their free time connected to the online world; therefore, brands have now to establish a presence in the digital world, in order to connect with its target audience. The entire dissertation revolves around the huge potential of social media as a marketing instrument that must be capitalized in today’s fast moving world. The main dilemma this dissertation attempts to resolve and provide an answer to, focus on how can Pantene target a younger age segment of consumers. To this end, celebrity endorsers are also worthy of being highlighted, as they perform a crucial role in influencing millennials’ behaviours and perceptions. A market research is performed, afterwards, in order to clarify the issues raised above and from which, a set of recommendations was produced. To conclude, a Teaching Note summarizes the case study and provides indications on how to explore it in a classroom environment.A presente dissertação oferece uma visão geral de importantes temas na área do marketing, como marketing e branding digitais, targeting, posicionamento, redes sociais como instrumentos de marketing e a eficácia de campanhas protagonizadas por celebridades. Estes tópicos são discutidos e analisados num caso de estudo focado na indústria do cuidado capilar, onde a Pantene ganha um lugar de destaque. O caso de estudo introduz esta indústria extremamente competitiva, cujas dinâmicas têm sido alvo de alterações devido à sensibilidade do consumidor médio relativamente ao preço. Adicionalmente, os consumidores passam, nos dias de hoje, a maioria do seu tempo livre conectados ao mundo online; por isso mesmo, as marcas têm de estabelecer a sua presença no mundo digital, de modo a estarem ligadas às suas audiências. Esta dissertação concerne o grande potencial das redes sociais enquanto instrumento de marketing que tem de ser concretizado nos altamente mutáveis dias de hoje. O grande dilema a que esta dissertação pretende dar resposta é o seguinte: como pode a Pantene atrair um segmento jovem de consumidores? Com este objectivo em mente, focamo-nos nas celebridades visto que elas desempenham um papel crucial em influenciar os comportamentos e percepções da Geração Y. Subsequentemente, de modo a clarificar as questões levantadas anteriormente, é apresentando um estudo de mercado, a partir do qual foi produzido um conjunto de recomendações. Para concluir, uma Nota de Ensino resume o caso de estudo e fornece indicações de como explorá-lo num ambiente de aula

Intra-group Light in Hickson Compact Groups

We have analyzed the intra-group light component of 3 Hickson Compact Groups (HCG 79, HCG 88 and HCG 95) with detections in two of them: HCG 79, with $46\pm11$ of the total $B$ band luminosity and HCG 95 with $11\pm26$. HCG 88 had no component detected. This component is presumably due to tidally stripped stellar material trapped in the group potential and represents an efficient tool to determine the stage of dynamical evolution and to map its gravitational potential. To detect this low surface brightness structure we have applied the wavelet technique OV\_WAV, which separates the different components of the image according to their spatial characteristic sizes.Comment: Small update on the associated institutions lis