189 research outputs found
Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae
Microscopic turbulence-flame interactions of thermonuclear fusion flames
occuring in Type Ia Supernovae were studied by means of incompressible direct
numerical simulations with a highly simplified flame description. The flame is
treated as a single diffusive scalar field with a nonlinear source term. It is
characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We
find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity
fluctuations, the local flame propagation speed does not significantly deviate
from S_L even in the presence of velocity fluctuations on scales below the
laminar flame thickness. This result is interpreted in the context of
subgrid-scale modeling of supernova explosions and the mechanism for
deflagration-detonation-transitions.Comment: 8 pages, 6 figures, accepted by Astrophys.
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How being appreciative creates change â theory in practice from health and social care in Scotland
This paper develops understanding of appreciative action research that generates curiosity and motivation as a better platform for collaborative change. Blending theory and practice it draws on the example of the My Home Life leadership programme in Scotland that explores the concepts and approaches of âCaring Conversationsâ and âplayful provocationâ in care homes for older people. The paper shows how they expand notions of appreciation and help people to deepen inquiry, explore values, acknowledge and express emotion without dispute or judgement, articulate tacit knowledge and give voice to things previously thought to be âunsayableâ. We explore how these generative approaches act as a powerful positive âdisruptionâ that brings existing relationships to life, supports a positive attitude to risk-taking and helps to devise new approaches to the local design and testing of approaches to problems.
Ultimately these approaches play an important part in developing understanding of how to do appreciative action research to enhance relationships and more strengths or assets-based and collaborative ways of working and so, to develop new possibilities for changing social systems and a more future-making orientation to action research
Discursive positioning and planned change in organizations
This study uses discursive positioning theory to explore how planned change messages influence organizational membersâ identity and the way they experienced organizational change. Based on an in-depth case study of a home healthcare and hospice organization that engaged in a multiyear planned change process, our analysis suggests that workers experienced salient change messages as constituting unfavorable identities, which were associated with the experiences of violation, recitation, habituation, or reservation. Our study also explores the way discursive and material contexts enabled and constrained the governing boardâs change messages as they responded to external and internal audiences. We highlight the importance of viewing messaging as a process of information transfer as well as discursive construction, which has important implications for the way change agents approach issues of sense making, emotionality, resistance, and materiality during planned change processes.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Reframing the university as an emergent organization: implications for strategic management and leadership in higher education
For the most part, the organisational forms that are currently being adopted by higher education institutions are grounded in the traditional corporate models of organisation that take a rational approach to organisational design and change management. Underlying this account is an assumption of organisational autonomy and the capacity of designated leaders to direct change processes to better align their institutions with societal demands or goals. However, a case is now being made for the consideration of alternative organisational theories or models that offer a different perception on the sources and patterns of organisational change in higher education. These theories perceive organisations more as emergent entities in which change is continuous, often unpredictable and arising mainly from local interactions. The paper surveys the implications that acceptance of the alternative paradigm might have for strategising and change leadership in higher education institutions. It suggests that the accommodation of these alterative paradigms of institutional development in higher education may itself be an emergent process and considers how future research and policy formulation relating to strategic management and leadership might facilitate positive outcomes in that process
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Rethinking âOrganizational Effectivenessâ as a Core Premise of Organization Development: Beyond Narrow Organizational Interests and Towards Wider Soulful Interventions
We contend that the dominant focus within the OD discourse is on organizations and their success (i.e. a preoccupation with âorganizational effectivenessâ) at the expense of wider responsibilities and obligations, and that the framing of âorganizational healthâ is overly narrow and partial (i.e. what is healthy for the organization rather than what is âhealthyâ at an individual or societal level). We offer some support for our assertion that OD initiatives focus too much on organizational effectiveness and organizational health and we discuss the scope for embracing a wider set of change imperatives. This involves distinguishing between âself-ishâ and âself-lessâ behaviour and drawing a distinction between distributive and generative forms of change activity Finally, we conclude by briefly sketching out how this could take shape in terms of what we have chosen to call âsoulful interventionsâ.
MAD statement: This opinion piece seeks to Make a Difference (MAD) by challenging the focus on organizational effectiveness and organizational health in organization development (OD) interventions. In doing so, we make a case for utilizing a wider set of change imperatives (e.g. increasing sustainability, enhancing social responsibility, addressing community needs) and set out how this should take shape in terms of a more inclusive and socially-informed bundle of approaches to OD
Five-year mortality in a cohort of people with schizophrenia in Ethiopia
<p>Abstract</p> <p>Background</p> <p>Schizophrenia is associated with a two to three fold excess mortality. Both natural and unnatural causes were reported. However, there is dearth of evidence from low and middle income (LAMIC) countries, particularly in Africa. To our knowledge this is the first community based report from Africa.</p> <p>Methods</p> <p>We followed a cohort of 307 (82.1% males) patients with schizophrenia for five years in Butajira, rural Ethiopia. Mortality was recorded using broad rating schedule as well as verbal autopsy. Standardized Mortality Ratio (SMR) was calculated using the mortality in the demographic and surveillance site as a reference.</p> <p>Result</p> <p>Thirty eight (12.4%) patients, 34 men (11.1%) and 4 women (1.3%), died during the five-year follow up period. The mean age (SD) of the deceased for both sexes was 35 (7.35). The difference was not statistically significant (p = 0.69). It was 35.3 (7.4) for men and 32.3 (6.8) for women. The most common cause of death was infection, 18/38 (47.4%) followed by severe malnutrition, 5/38 (13.2%) and suicide 4/38 (10.5%). The overall SMR was 5.98 (95% CI = 4.09 to7.87). Rural residents had lower mortality with adjusted hazard ratio (HR) of 0.30 (95% CI = 0.12-0.69) but insidious onset and antipsychotic treatment for less than 50% of the follow up period were associated with higher mortality, adjusted HR 2.37 (95% CI = 1.04-5. 41) and 2.66(1.054-6.72) respectively.</p> <p>Conclusion</p> <p>The alarmingly high mortality observed in this patient population is of major concern. Most patients died from potentially treatable conditions. Improving medical and psychiatric care as well as provision of basic needs is recommended.</p
Changes in body weight, body composition and cardiovascular risk factors after long-term nutritional intervention in patients with severe mental illness: an observational study
<p>Abstract</p> <p>Background</p> <p>Compared with the general population, individuals with severe mental illness (SMI) have increased prevalence rates of obesity and greater risk for cardiovascular disease. This study aimed to investigate the effects of a long term nutritional intervention on body weight, body fat and cardiovascular risk factors in a large number of patients with SMI.</p> <p>Methods</p> <p>Nine hundred and eighty-nine patients with a mean ± S.D age of 40 ± 11.7 yrs participated in a 9 mo nutritional intervention which provided personalised dietetic treatment and lifestyle counselling every two weeks. Patients had an average body mass index (BMI) of 34.3 ± 7.1 kg.m<sup>-2 </sup>and body weight (BW) of 94.9 ± 21.7 kg. Fasted blood samples were collected for the measurement of glucose, total cholesterol, triglycerides and HDL- cholesterol. All measurements were undertaken at baseline and at 3 mo, 6 mo and 9 mo of the nutritional intervention.</p> <p>Results</p> <p>Four hundred and twenty-three patients of 989 total patients' cases (42.8%) dropped out within the first 3 months. Two hundred eighty-five completed 6 months of the program and 145 completed the entire 9 month nutritional intervention. There were progressive statistically significant reductions in mean weight, fat mass, waist and BMI throughout the duration of monitoring (p < 0.001). The mean final weight loss was 9.7 kg and BMI decreased to 30.7 kg.m<sup>-2 </sup>(p < 0.001). The mean final fat mass loss was 8.0 kg and the mean final waist circumference reduction was 10.3 cm (p < 0.001) compared to baseline. Significant and continual reductions were observed in fasting plasma glucose, total cholesterol and triglycerides concentrations throughout the study (p < 0.001).</p> <p>Conclusion</p> <p>The nutritional intervention produced significant reductions in body weight, body fat and improved the cardiometabolic profile in patients with SMI. These findings indicate the importance of weight-reducing nutritional intervention in decreasing the cardiovascular risk in patients with SMI.</p
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