1,731 research outputs found
High-speed Photometric Observations of ZZ Ceti White Dwarf Candidates
We present high-speed photometric observations of ZZ Ceti white dwarf
candidates drawn from the spectroscopic survey of bright DA stars from the
Villanova White Dwarf Catalog by Gianninas et al., and from the recent
spectroscopic survey of white dwarfs within 40 parsecs of the Sun by Limoges et
al. We report the discovery of six new ZZ Ceti pulsators from these surveys,
and several photometrically constant DA white dwarfs, which we then use to
refine the location of the ZZ Ceti instability strip.Comment: 4 pages, 1 table, 2 figures, to appear in "19th European White Dwarf
Workshop" in the ASP Conference Serie
Spatial Structure and Activity of Sedimentary Microbial Communities Underlying a Beggiatoa spp. Mat in a Gulf of Mexico Hydrocarbon Seep
Background: Subsurface fluids from deep-sea hydrocarbon seeps undergo methane- and sulfur-cycling microbial transformations near the sediment surface. Hydrocarbon seep habitats are naturally patchy, with a mosaic of active seep sediments and non-seep sediments. Microbial community shifts and changing activity patterns on small spatial scales from seep to non-seep sediment remain to be examined in a comprehensive habitat study. Methodology/Principal Findings: We conducted a transect of biogeochemical measurements and gene expression related to methane- and sulfur-cycling at different sediment depths across a broad Beggiatoa spp. mat at Mississippi Canyon 118 (MC118) in the Gulf of Mexico. High process rates within the mat (,400 cm and,10 cm from the mat’s edge) contrasted with sharply diminished activity at,50 cm outside the mat, as shown by sulfate and methane concentration profiles, radiotracer rates of sulfate reduction and methane oxidation, and stable carbon isotopes. Likewise, 16S ribosomal rRNA, dsrAB (dissimilatory sulfite reductase) and mcrA (methyl coenzyme M reductase) mRNA transcripts of sulfate-reducing bacteria (Desulfobacteraceae and Desulfobulbaceae) and methane-cycling archaea (ANME-1 and ANME-2) were prevalent at the sediment surface under the mat and at its edge. Outside the mat at the surface, 16S rRNA sequences indicated mostly aerobes commonly found in seawater. The seep-related communities persisted at 12–20 cm depth inside and outside the mat. 16S rRNA transcripts and V6-tags reveal that bacterial and archaeal diversity underneath the mat are similar to eac
The importance of both setting and intensity of physical activity in relation to non-clinical anxiety and depression
Physical activity is associated with good physical and mental health. Current recommendations suggest that people should achieve 30 minutes of moderate-intensity activity most days of the week to gain health benefits. This activity may be accumulated in leisure time, in active commuting, at work or in the home. Here we look at the cross-sectional relationship between physical activity and mental health as measured by the HADS anxiety and depression scores in a sample of 1,742 participants from a Scottish general population survey. The participants were men and women in three age cohorts aged around 24, 44 and 64 years who, in 1995, were interviewed face to face and also self-completed the HADS depression and anxiety scale. Respondents reported their levels of physical activity at work, in the home and in leisure time; the intensities of activity were also determined. Physical activity was related to depression scores but not to anxiety scores. There was no relationship between work physical activity and depression score. Among women, depression score increased with each additional episode of vigorous home activity. In both sexes, depression score decreased with each additional episode of vigorous leisure activity, but among men the decrease in depression score with moderate leisure activity was reversed if a lot of moderate activity was undertaken. We have found a variable relationship between depression scores and various settings for physical activity. Researchers, policymakers and practitioners who are interested in the relationship between physical activity and mental health should take into account the setting for activity as well as frequency, duration and intensity of activity
Exposure to, and searching for, information about suicide and self-harm on the Internet:Prevalence and predictors in a population based cohort of young adults
AbstractBackgroundThere is concern over the potential impact of the Internet on self-harm and suicidal behaviour, particularly in young people. However, little is known about the prevalence and patterns of suicide/self-harm related Internet use in the general population.MethodsCross sectional study of 3946 of the 8525 participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) who were sent a self-report questionnaire including questions on suicide/self-harm related Internet use and self-harm history at age 21 years.ResultsSuicide/self-harm related Internet use was reported by 22.5% (886/3946) of participants; 11.9% (470/3946) had come across sites/chatrooms discussing self-harm or suicide, 8.2% (323/3946) had searched for information about self-harm, 7.5% (296/3946) had searched for information about suicide and 9.1% (357/3946) had used the Internet to discuss self-harm or suicidal feelings. Suicide/self-harm related Internet use was particularly prevalent amongst those who had harmed with suicidal intent (70%, 174/248), and was strongly associated with the presence of suicidal thoughts, suicidal plans, and history of self-harm. Sites offering help, advice, or support were accessed by a larger proportion of the sample (8.2%, 323/3946) than sites offering information on how to hurt or kill yourself (3.1%, 123/3946). Most individuals (81%) who had accessed these potentially harmful sites had also accessed help sites.Limitations(i) There were differences between questionnaire responders and non-responders which could lead to selection bias and (ii) the data were cross-sectional, and we cannot conclude that associations are causal.ConclusionsSuicide/self-harm related Internet use is common amongst young adults, particularly amongst those with suicidal thoughts and behaviour. Both harmful and helpful sites were accessed, highlighting that the Internet presents potential risks but also offers opportunities for suicide prevention
A Golf Programme for People with Severe and Enduring Mental Health Problems
This article reports a pioneering golf programme for people with severe and enduring mental health problems. Following a discussion of the problems and possibilities of golf as a form of physical activity for this group, we outline the structure, organisation, and ethos of the golf programme. Through an analysis of qualitative case study data collected during the programme, we discuss the response to the programme from service users and mental health professionals. We conclude by highlighting aspects of the programme which were critical to its success and offering suggestions for further initiatives in this area
Examining exercise dependence symptomatology from a self-determination perspective
Background: Based on the theoretical propositions of Self-Determination Theory (SDT; Deci & Ryan, 1985) this study examined whether individuals classified as “nondependent-symptomatic” and “nondependent-asymptomatic” for exercise dependence differed in terms of the level of exercise-related psychological need satisfaction and self-determined versus controlling motivation they reported. Further, we examined if the type of motivational regulations predicting exercise behaviour differed among these groups.
Methods: Participants (N = 339), recruited from fitness, community, and retail settings, completed measures of exercise-specific psychological need satisfaction, motivational regulations, exercise behaviour and exercise dependence.
Results: Individuals who were nondependent-symptomatic for exercise dependence reported higher levels of competence need satisfaction and all forms of motivational regulation, compared to nondependent-asymptomatic individuals. Introjected regulation approached significance as a positive predictor of strenuous exercise behaviour for symptomatic individuals. Identified regulation was a positive predictor of strenuous exercise for asymptomatic individuals.
Conclusions: The findings reinforce the applicability of SDT to understanding engagement in exercise
Motivations and barriers to prosthesis users participation in physical activity, exercise and sport : a review of the literature
The UK will host the Paralympics in 2012 and the Commonwealth Games in 2014 showcasing the talents of elite athletes and aiming to inspire the population to become involved. However, low levels of physical activity (PA) are prevalent: only 40% of men and 28% of women meet the minimum UK recommendations. The limb absent population is no exception. To determine if people with limb amputations are participating in physical activity and sport; whether post-amputation activity levels match pre-amputation levels; and if there are motivations and barriers to participation. Study design: Literature review Five reviewers systematically search of peer reviewed and gray literature in seven bibliographic databases and the Cochrane Library. Results: Following rigorous elimination, 12 articles were finally included in the review and critically appraised. Four themes were identified: components, rehabilitation outcomes, body image and motivations and barriers to participation. People with limb absence are not participating in PA conducive to health benefits, and only a minority participate in exercise and sports. Participation following amputation does not mirror that of pre-amputation levels, and more barriers than motivations exist to adopting and maintaining a physically active lifestyle. This literature review aims to inform those involved in rehabilitation and ongoing care of those with limb absence about what motivates or precludes their participation in physical activity, exercise and sport. Such knowledge could be applied to improving health and well being in this population
A phenomenological exploration of exercise mental toughness: perceptions of exercise leaders and regular exercisers
Although elite sport has provided an ideal context for exploring mental toughness (MT), currently, there is scant research examining how this construct might be equally applicable in exercise settings, where high rates of attrition have been reported. The present research, therefore, aimed to address this gap, and to understand and conceptualise exercise mental toughness (EMT) through in-depth phenomenological interviews with a range of exercise leaders and exercise participants. Seven qualified and experienced exercise leaders and seven regular and frequent exercisers from formal exercise environments (i.e. gym and fitness classes) were interviewed. Interviews were digitally recorded, transcribed verbatim and analysed independently by members of the interdisciplinary research team. Key themes were agreed and member checking was used to promote trustworthiness of interpretations. MT was recognisable in exercise settings, with 10 general dimensions found to be relatively consistent with conceptualisations derived from elite sport (e.g. commitment, focus, emotional control, etc.). Importantly, present findings reveal how mentally tough exercisers think and behave in exercise settings. Some negative consequences were also reported such as over-training and training with injuries. The article also discusses how components of EMT may be valuable in terms of exercise maintenance and relapse prevention during exercise behaviour change
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