The Frequency of Active and Quiescent Galaxies with Companions: Implications for the Feeding of the Nucleus

We analyze the idea that nuclear activity, either AGN or star formation, can be triggered by interactions, studying the percentage of active, HII and quiescent galaxies with companions. Our sample was selected from the Palomar survey, and avoids selection biases faced by previous studies. The comparison between the local galaxy density distributions showed that in most cases there is no statistically significant difference among galaxies of different activity types. The comparison of the percentage of galaxies with nearby companions showed that there is a higher percentage of LINERs, transition, and absorption line galaxies with companions than Seyferts and HII galaxies. However, we find that when we consider only galaxies of similar morphological types (ellipticals or spirals), there is no difference in the percentage of galaxies with companions among different activity types, indicating that the former result was due to the morphology-density effect. Also, only small differences are found when we consider galaxies with similar Halpha luminosities. The comparison between HII galaxies of different Halpha luminosities shows that there is a significantly higher percentage of galaxies with companions among the higher luminosity HII galaxies, indicating that interactions increase the amount of circumnuclear star formation, in agreement with previous results. The fact that we find that galaxies of different activity types have the same percentage of companions, suggests that interactions between galaxies is not a necessary condition to trigger the nuclear activity in AGNs. We compare our results with previous ones and discuss their implications. (abridged)Comment: 30 pages, including 6 figures and 3 tables. To appear in The Astronomical Journal, November issu

Watching videos together in social Virtual Reality: An experimental study on user’s QoE

In this paper, we describe a user study in which pairs of users watch a video trailer and interact with each other, using two social Virtual Reality (sVR) systems, as well as in a face-to-face condition. The sVR systems are: Facebook Spaces, based on puppet-like customized avatars, and a video-based sVR system using photo-realistic virtual user representations. We collect subjective and objective data to analyze users’ Quality of Experience (QoE) and compare their interaction in VR to that observed during the real-life scenario. Our results show that the experience delivered by the video-based sVR system is comparable with real-life settings, while the puppet-based avatars limit the perceived q

Psychology in the realm of sport injury : What it is all about

Sport injuries are a constant in physical activity and sport and represent, to a greater or lesser degree, an obstacle that most athletes have to face and which could have an impact on economical, occupational and educational aspects, as well as on physical and psychological health. Traditionally, sport injury was deemed the result of biomechanical forces exerted on the body and sustained during participation in sport activity, under which perspective the athlete is considered merely as the container of a set of parts that break down and must be repaired. In contrast, Sport Psychology has brought the individual into a central active role, both when sustaining and recovering from an injury. This paper promotes a psychological perspective on sport injury and reviews the main psychological models posed for both the pre-injury and the post-injury phases. Finally, the paper addresses some of the main problems encountered by research on sport injury and sets out several guidelines for future research in the field

Psychology in the realm of sport injury : What it is all about

Sport injuries are a constant in physical activity and sport and represent, to a greater or lesser degree, an obstacle that most athletes have to face and which could have an impact on economical, occupational and educational aspects, as well as on physical and psychological health. Traditionally, sport injury was deemed the result of biomechanical forces exerted on the body and sustained during participation in sport activity, under which perspective the athlete is considered merely as the container of a set of parts that break down and must be repaired. In contrast, Sport Psychology has brought the individual into a central active role, both when sustaining and recovering from an injury. This paper promotes a psychological perspective on sport injury and reviews the main psychological models posed for both the pre-injury and the post-injury phases. Finally, the paper addresses some of the main problems encountered by research on sport injury and sets out several guidelines for future research in the field

TCT-695 Clinical Impact and Evolution Of Mitral Regurgitation Following Transcatheter Aortic Valve Replacement: A Meta-Analysis

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Proteomic analysis of Chromobacterium violaceum and its adaptability to stress

Chromobacterium violaceum (C. violaceum) occurs abundantly in a variety of ecosystems, including ecosystems that place the bacterium under stress. This study assessed the adaptability of C. violaceum by submitting it to nutritional and pH stresses and then analyzing protein expression using bi-dimensional electrophoresis (2-DE) and Maldi mass spectrometry. Chromobacterium violaceum grew best in pH neutral, nutrient-rich medium (reference conditions); however, the total protein mass recovered from stressed bacteria cultures was always higher than the total protein mass recovered from our reference culture. The diversity of proteins expressed (repressed by the number of identifiable 2-DE spots) was seen to be highest in the reference cultures, suggesting that stress reduces the overall range of proteins expressed by C. violaceum. Database comparisons allowed 43 of the 55 spots subjected to Maldi mass spectrometry to be characterized as containing a single identifiable protein. Stress-related expression changes were noted for C. violaceum proteins related to the previously characterized bacterial proteins: DnaK, GroEL-2, Rhs, EF-Tu, EF-P; MCP, homogentisate 1,2-dioxygenase, Arginine deiminase and the ATP synthase β-subunit protein as well as for the ribosomal protein subunits L1, L3, L5 and L6. The ability of C. violaceum to adapt its cellular mechanics to sub-optimal growth and protein production conditions was well illustrated by its regulation of ribosomal protein subunits. With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures. Curiously, C. violeaceum cultures were also observed to lose their violet color under stress, which suggests that the violacein pigment biosynthetic pathway is affected by stress. Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production. Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum

Stability-indicating liquid chromatographic and UV spectrophotometric methods for the quantification of ciprofibrate in capsules and tablets

This study describes the development and evaluation of stability-indicating liquid chromatographic (LC) and UV spectrophotometric methods for the quantification of ciprofibrate (CPF) in tablets and capsules. Isocratic LC separation was achieved on a RP18 column using a mobile phase of o-phosphoric acid (0.1% v/v), adjusted to pH 3.0 with triethylamine (10% v/v) and acetonitrile (35:65 v/v), with a flow rate of 1.0 mL min-1. Detection was achieved with a photodiode array detector at 233 nm. For the spectrophotometric analysis, ethanol and water were used as the solvent and a wavelength of 233 nm was selected for the detection. The methods were validated according to International Conference on Harmonization (ICH) guidelines for validating analytical procedures. Statistical analysis showed no significant difference between the results obtained by the two methods. The proposed methods were successfully applied to the CPF quality-control analysis of tablets and capsules