418 research outputs found
Heating of the Intracluster Gas in the Triangulum Australis Cluster
ASCA and ROSAT X-ray data are used to obtain two-dimensional maps of the gas
temperature, pressure and specific entropy in the Triangulum Australis cluster
of galaxies. We find that this hot (T_e=10.3+-0.8 keV) system probably has a
temperature peak (T_e>12 keV) at the cluster core, which approximately
corresponds to the adiabatic relation. An underdense gas sector, found in the
ROSAT cluster image eastward of the core, has a higher temperature than average
at that radius. At this higher temperature, the gas pressure in this region is
equal to that of the rest of the cluster at the same radius, but the specific
entropy of this gas is significantly higher (although the temperature
difference itself is only marginally significant). We speculate that the
existence of this region of underdense high-entropy gas, as well as the
adiabatic central temperature peak, indicate recent or ongoing heating of the
intergalactic medium in this cluster. The most probable source of such heating
is a subcluster merger, for which the hydrodynamic simulations predict a
qualitatively similar temperature structure. We point out that entropy maps can
provide a physically meaningful way of diagnosing merging clusters and
comparing the predictions of merger simulations to the data.Comment: Text revised to give more technical details and clarify discussion.
Accepted for ApJ Letters. Latex, 5 pages incl. figures, macros include
The future of leadership development: The importance of identity, multi-level approaches, self-leadership, physical fitness, shared leadership, networking, creativity, emotions, spirituality and on-boarding processes
Role Preferences in Medical Decision Making: Relevance and Implications for Health Preference Research
Turning a lost reef ecosystem into a national restoration program
Achieving a sustainable socioecological future now requires large-scale environmental repair across legislative borders. Yet, enabling large-scale conservation is complicated by policy-making processes that are disconnected from socioeconomic interests, multiple sources of knowledge, and differing applications of policy. We considered how a multidisciplinary approach to marine habitat restoration generated the scientific evidence base, community support, and funding needed to begin the restoration of a forgotten, functionally extinct shellfish reef ecosystem. The key actors came together as a multidisciplinary community of researchers, conservation practitioners, recreational fisher communities, and government bodies that collaborated across sectors to rediscover Australia's lost shellfish reefs and communicate the value of its restoration. Actions undertaken to build a case for large-scale marine restoration included synthesizing current knowledge on Australian shellfish reefs and their historical decline, using this history to tell a compelling story to spark public and political interest, integrating restoration into government policy, and rallying local support through community engagement. Clearly articulating the social, economic, and environmental business case for restoration led to state and national funding for reef restoration to meet diverse sustainability goals (e.g., enhanced biodiversity and fisheries productivity) and socioeconomic goals (e.g., job creation and recreational opportunities). A key lesson learned was the importance of aligning project goals with public and industry interests so that projects could address multiple political obligations. This process culminated in Australia's largest marine restoration initiative and shows that solutions for large-scale ecosystem repair can rapidly occur when socially valued science acts on political opportunities
Population genetics of trypanosoma brucei rhodesiense: clonality and diversity within and between foci
African trypanosomes are unusual among pathogenic protozoa in that they can undergo their complete morphological life cycle in the tsetse fly vector with mating as a non-obligatory part of this development. Trypanosoma brucei rhodesiense, which infects humans and livestock in East and Southern Africa, has classically been described as a host-range variant of the non-human infective Trypanosoma brucei that occurs as stable clonal lineages. We have examined T. b. rhodesiense populations from East (Uganda) and Southern (Malawi) Africa using a panel of microsatellite markers, incorporating both spatial and temporal analyses. Our data demonstrate that Ugandan T. b. rhodesiense existed as clonal populations, with a small number of highly related genotypes and substantial linkage disequilibrium between pairs of loci. However, these populations were not stable as the dominant genotypes changed and the genetic diversity also reduced over time. Thus these populations do not conform to one of the criteria for strict clonality, namely stability of predominant genotypes over time, and our results show that, in a period in the mid 1990s, the previously predominant genotypes were not detected but were replaced by a novel clonal population with limited genetic relationship to the original population present between 1970 and 1990. In contrast, the Malawi T. b. rhodesiense population demonstrated significantly greater diversity and evidence for frequent genetic exchange. Therefore, the population genetics of T. b. rhodesiense is more complex than previously described. This has important implications for the spread of the single copy T. b. rhodesiense gene that allows human infectivity, and therefore the epidemiology of the human disease, as well as suggesting that these parasites represent an important organism to study the influence of optional recombination upon population genetic dynamics
Erratum to: Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species
Upon publication of the original article [1], it was noticed that Dr Papanicolaou’s surname was spelt incorrectly. The correct spelling is “Papanicolaou”, as shown in the author list of this erratum.Additional co-authors: A. Anderson, S. Asgari, P. G. Board, A. Bretschneider, P. M. Campbell, T. Chertemps, J. T. Christeller, C. W. Coppin, S. J. Downes, G. Duan, C. A. Farnsworth, R. T. Good, L. B. Han, Y. C. Han, K. Hatje, I. Horne, Y. P. Huang, D. S. T. Hughes, E. Jacquin-Joly, W. James, S. Jhangiani, M. Kollmar, S. S. Kuwar, S. Li, N-Y. Liu, M. T. Maibeche, J. R. Miller, N. Montagne, T. Perry, J. Qu, S. V. Song, G. G. Sutton, H. Vogel, B. P. Walenz, W. Xu, H-J. Zhang, Z. Zou, P. Batterham, O. R. Edwards, R. Feyereisen, R. A. Gibbs, D. G. Heckel, A. McGrath, C. Robin, S. E. Scherer, K. C. Worley, Y. D. W
Natural law, non-voluntary euthanasia, and public policy
© 2019 by Emerald Publishing Limited. Natural Law philosophy asserts that there are universally binding and universally evident principles that can be determined to guide the actions of persons. Moreover, many of these principles have been enshrined in both statute and common law, thus ensuring their saliency for staff and institutions charged with palliative care. The authors examine the often emotive and politicized matter of (non-voluntary) euthanasia – acts or omissions made with the intent of causing or hastening death – with reference to Natural Law philosophy. This leads us to propose a number of important public policy remedies to ensure dignity in dying for the patient, and their associates
Mental health and health behaviours before and during the initial phase of the COVID-19 lockdown: longitudinal analyses of the UK Household Longitudinal Study.
Background There are concerns that COVID-19 mitigation measures, including the ‘lockdown’, may have unintended health consequences. We examined trends in mental health and health behaviours in the UK before and during the initial phase of the COVID-19 lockdown and differences across population subgroups.
Methods Repeated cross-sectional and longitudinal analysis of the UK Household Longitudinal Study, including representative samples of over 27,000 adults (aged 18+) interviewed in four survey waves between 2015 and 2020. A total of 9748 adults had complete data for longitudinal analyses. Outcomes included psychological distress (General Health Questionnaire-12), loneliness, current cigarette smoking, use of e-cigarettes and alcohol consumption. Cross-sectional prevalence estimates were calculated and multilevel Poisson regression assessed associations between time period and the outcomes of interest, as well as differential associations by age, gender, education level and ethnicity.
Results Psychological distress increased 1 month into lockdown with the prevalence rising from 19.4% (95% CI 18.7% to 20.1%) in 2017–2019 to 30.6% (95% CI 29.1% to 32.3%) in April 2020 (RR=1.3, 95% CI 1.2 to 1.4). Groups most adversely affected included women, young adults, people from an Asian background and those who were degree educated. Loneliness remained stable overall (RR=0.9, 95% CI 0.6 to 1.5). Smoking declined (RR=0.9, 95% CI=0.8,1.0) and the proportion of people drinking four or more times per week increased (RR=1.4, 95% CI 1.3 to 1.5), as did binge drinking (RR=1.5, 95% CI 1.3 to 1.7).
Conclusions Psychological distress increased 1 month into lockdown, particularly among women and young adults. Smoking declined, but adverse alcohol use generally increased. Effective measures are required to mitigate negative impacts on health
- …