2,745 research outputs found
The catalogue of OB associations in IC 1613
We present a catalogue of OB associations in IC 1613. Using an automatic and
objective method (Battinelli's 1991 technique) 60 objects were found. The size
distribution reveals a significant peak at about 60 parsecs if a distance
modulus of 24.27 mag is assumed. Spatial distributions of the detected
associations and H II regions are strongly correlated.Comment: 5 pages, 3 figures, A&A accepte
The influence of massive stars in the interstellar medium of IC 1613: the supernova remnant S8 and the nebula S3 associated with a WO star
We present a detailed kinematical analysis of two selected nebulae in the
Local Group irregular galaxy IC 1613. The nebulae are: S8, the only known
supernova remnant in this galaxy, and S3, a Wolf-Rayet nebula associated with
the only WO star in this galaxy. For S8, we have obtained and analyzed its
radial velocity field, where we found complex profiles which can be fitted by
several velocity components. These profiles also show the presence of high
velocity, low density gas. From this, we have obtained the expansion velocity,
estimated the preshock density and calculated the basic kinematical parameters
of this SNR. We suggest that in S8 we are seing a SNR partially hidden by dust.
This suggestion comes from the fact that the SNR is located between two
superbubbles where a ridge of obscured material unveils the existence of dust.
Moreover, we show that this hypothesis prevails when energetic arguments are
taken into account. In the case of S3, this nebula shows bipolar structure. By
means of its kinematics, we have analyzed its two lobes, the ``waist'', as well
as its relation with the nearest superbubbles. For the first time we are able
to see closed the NW lobe, showing a clover leaf shape. This fact allows a
better quantitative knowledge of the nebula as a whole. Furthermore, we found
evidence of an expansion motion in the NW lobe. In the light of our results, we
can express that these nebulae are the product of very massive stellar
evolution. It is surprising the influence these stars still have in shaping
their surrounding gas, and on the energy liberation towards the interstellar
medium of this galaxy.Comment: Accepted for publication in the Astronomical Journal, July issue. 11
pages, 12 figures. High resolution figures can be found at
http://www.inaoep.mx/~mago/PAPERS/AJ
Determinants of the intention to use performance-enhancing substances among Portuguese gym users
The present study examined the determinants of the intentions to use prohibited performance- enhancing substances (PES) and the hypothesis of gender and PES use influencing Theory of Planned Behavior (TPB) variables. A TPB approach was used. A convenience sample of Portuguese gym users (n = 453) completed an anonymous web-based survey. Variance-based structural equation modeling, multigroup analysis strategy, latent mean analysis approach and one-way ANOVA analysis were used. The findings showed that, at structural level, results support the TPB framework in terms of characterizing and predicting intentions to PES use in the gym users sample, and that subjective norms were the strongest predictor of PES use intentions. Female and male differed in intentions to use PES, subjective norms and beliefs. However, the predictive model in study remains invariable in both groups. Concerning PES use, results showed the existence of a significant difference, regarding all the TPB´s constructs of the PES users and nonusers’ groups, and that the predictive capacity of each predictor was different for each group. Psychological strategies should be based on subjective norms, alongside beliefs and attitudes towards PES use, since these variables influence the intention to use PES in that particular population
Coaches’ migration: decisions and perceived importance of international experience
The migration of coaches is a topic that has seen increasing research interest in recent years. Discussions are evolving around the factors driving coaches' migration, their experiences, and perceptions held by other sports stakeholders. This study aimed to explore the decision-making processes of coaches regarding migration and their views on the phenomenon. A total of 68 coaches, both with and without international experience, participated in the study. Data collection involved an online survey comprisingclosed-ended questions. For data analysis, we employed a One-Way ANOVA to draw comparisons across independent variables. Interestingly, coaches with international experience have been more frequently approached with offers than their counterparts without such experience. Nevertheless, the majority of the coaches did not perceive foreign coaches as essential to sports development. Coaches with international backgrounds expressed a belief that native coaches should exclusively coach their national teams. Overall, coaches did not highly value international placements or experience. These unexpected findings have significant implications for coach training programs globally. The results are further explored in the context of the expertise required to work in a globalised sports setting and interact with stakeholders from diverse cultural backgrounds
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