799 research outputs found
On long-term modulation of the Sun’s magnetic cycle
We utilize reconstructions based on cosmogenic radionuclides as well as direct observations of solar magnetic activity, to argue that the solar dynamo has operated similarly to the present day for at least the past 10 000 yr. The persistence of the 87-yr Gleissberg cycle throughout supermodulation events suggests that the Hale and Schwabe cycles continue independently of the modulational mechanism for activity. We further analyse behaviour of solar activity during the Spörer and Maunder Minima. Such grand minima recur with the characteristic de Vries period of approximately 208 yr but their incidence is modulated by the Hallstatt cycle with a characteristic period of around 2300 yr.We ascribe the latter to supermodulation, caused by breaking the symmetry of the dynamo pattern. Finally, we emphasize the need for further calculations in order to determine the effects of changes in solar field morphology and symmetry on the solar wind and on cosmic ray deflection
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Twelve tips for designing and implementing an academic coaching program
Coaching has become increasingly popular as a mechanism to support learning across the health professions education (HPE) continuum. While there is a growing body of literature in this area, there is minimal guidance related to the design and implementation of academic coaching in health professional courses. This paper seeks to contribute to this literature by presenting guidance for academic developers who are considering introducing academic coaching into a health professional course. The 12 tips are based on the authors’ collective experiences of designing and implementing academic coaching in university medical courses in Australia and the UK. Although focused on medical education, this paper is intended to have applicability across the health professions, and potentially across university and postgraduate training contexts. Together, the tips offer a strategic and operational framework to guide the design and implementation of academic coaching initiatives in health professions education.The author(s) reported there is no funding associated with the work featured in this article
Dementia in residential care: education intervention trial (DIRECT); protocol for a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>There is scope to improve the quality of life (QOL) of people with dementia living in residential care facilities (RCF). The DIRECT study will determine if delivery of education to General Practitioners (GPs) and care staff improves the quality of life of residential care recipients with cognitive impairment.</p> <p>Methods/Design</p> <p>A prospective randomised controlled trial conduced in residential aged care facilities in the metropolitan area of Perth, Western Australia. Participants are care facility residents, aged 65 years and older and with mini-mental state examination scores less than 25. GPs and care facility staff have been independently randomised to intervention or control groups. An education programme, designed to meet the perceived needs of learners, will be delivered to GPs and care staff in the intervention groups. The primary outcome of the study will be quality of life of the people with dementia, measured using the QOL-Alzheimer's Disease Scale (QOL-AD) and Alzheimer Disease Related QOL Scale (ADRQL), 4 weeks and 6 months after the conclusion of the education intervention.</p> <p>Results</p> <p>Recruitment of 351 people with dementia, cared for by staff in 39 residential facilities and 55 GPs, was undertaken between May 2007 and July 2008. Collection of baseline data is complete. Education has been delivered to GPs and Care staff between September 2008 and July 2009. Follow- up data collection is underway.</p> <p>Discussion</p> <p>The study results will have tangible implications for proprietors, managers and staff from the residential care sector and policy makers. The results have potential to directly benefit the quality of life of both patients and carers.</p> <p>Trial registration</p> <p>These trial methods have been prospectively registered (ACTRN12607000417482).</p
Improving the evidence base of Markov models used to estimate the costs of scaling up antiretroviral programmes in resource-limited settings
<p>Abstract</p> <p>Background</p> <p>Despite concerns about affordability and sustainability, many models of the lifetime costs of antiretroviral therapy (ART) used in resource limited settings are based on data from small research cohorts, together with pragmatic assumptions about life-expectancy. This paper revisits these modelling assumptions in order to provide input to future attempts to model the lifetime costs and the costs of scaling up ART.</p> <p>Methods</p> <p>We analysed the determinants of costs and outcomes in patients receiving ART in line with standard World Health Organization (WHO) guidelines for resource poor settings in a private sector managed ART programme in South Africa. The cohort included over 5,000 patients with up to 4 years (median 19 months) on ART. Generalized linear and Cox proportional hazards regression models were used to establish cost and outcome determinants respectively.</p> <p>Results</p> <p>The key variables associated with changes in mean monthly costs were: being on the second line regimen; receiving ART from 4 months prior to 4 months post treatment initiation; having a recent or current CD4 count <50 cells/µL or 50-199 cells/µl; having mean ART adherence <75% as determined by monthly pharmacy refill data; and having a current or recent viral load >100,000 copies/mL. In terms of the likelihood of dying, the key variables were: baseline CD4 count<50 cells/µl (particularly during the first 4 months on treatment); current CD4 count <50 cells/µl and 50-199 cells/µl (particularly during later periods on treatment); and being on the second line regimen. Being poorly adherent and having an unsuppressed viral load was also associated with a higher likelihood of dying.</p> <p>Conclusions</p> <p>While there are many unknowns associated with modelling the resources needed to scale-up ART, our analysis has suggested a number of key variables which can be used to improve the state of the art of modelling ART. While the magnitude of the effects associated with these variables would be likely to differ in other settings, the variables influencing costs and survival are likely to be generalizable. This is of direct relevance to those concerned about assessing the long-term costs and sustainability of expanded access to ART.</p
Genetic determinants of co-accessible chromatin regions in activated T cells across humans.
Over 90% of genetic variants associated with complex human traits map to non-coding regions, but little is understood about how they modulate gene regulation in health and disease. One possible mechanism is that genetic variants affect the activity of one or more cis-regulatory elements leading to gene expression variation in specific cell types. To identify such cases, we analyzed ATAC-seq and RNA-seq profiles from stimulated primary CD4+ T cells in up to 105 healthy donors. We found that regions of accessible chromatin (ATAC-peaks) are co-accessible at kilobase and megabase resolution, consistent with the three-dimensional chromatin organization measured by in situ Hi-C in T cells. Fifteen percent of genetic variants located within ATAC-peaks affected the accessibility of the corresponding peak (local-ATAC-QTLs). Local-ATAC-QTLs have the largest effects on co-accessible peaks, are associated with gene expression and are enriched for autoimmune disease variants. Our results provide insights into how natural genetic variants modulate cis-regulatory elements, in isolation or in concert, to influence gene expression
Association of rs780094 in GCKR with Metabolic Traits and Incident Diabetes and Cardiovascular Disease: The ARIC Study
The minor T-allele of rs780094 in the glucokinase regulator gene (GCKR) associates with a number of metabolic traits including higher triglyceride levels and improved glycemic regulation in study populations of mostly European ancestry. Using data from the Atherosclerosis Risk in Communities (ARIC) Study, we sought to replicate these findings, examine them in a large population-based sample of African American study participants, and to investigate independent associations with other metabolic traits in order to determine if variation in GKCR contributes to their observed clustering. In addition, we examined the association of rs780094 with incident diabetes, coronary heart disease (CHD), and stroke over up mean follow-up times of 8, 15, and 15 years, respectively.Race-stratified analyses were conducted among 10,929 white and 3,960 black participants aged 45-64 at baseline assuming an additive genetic model and using linear and logistic regression and Cox proportional hazards models.Previous findings replicated among white participants in multivariable adjusted models: the T-allele of rs780094 was associated with lower fasting glucose (p = 10(-7)) and insulin levels (p = 10(-6)), lower insulin resistance (HOMA-IR, p = 10(-9)), less prevalent diabetes (p = 10(-6)), and higher CRP (p = 10(-8)), 2-h postprandial glucose (OGTT, p = 10(-6)), and triglyceride levels (p = 10(-31)). Moreover, the T-allele was independently associated with higher HDL cholesterol levels (p = 0.022), metabolic syndrome prevalence (p = 0.043), and lower beta-cell function measured as HOMA-B (p = 0.011). Among black participants, the T-allele was associated only with higher triglyceride levels (p = 0.004) and lower insulin levels (p = 0.002) and HOMA-IR (p = 0.013). Prospectively, the T-allele was associated with reduced incidence of diabetes (p = 10(-4)) among white participants, but not with incidence of CHD or stroke.Our findings indicate rs780094 has independent associations with multiple metabolic traits as well as incident diabetes, but not incident CHD or stroke. The magnitude of association between the SNP and most traits was of lower magnitude among African American compared to white participants
The Amsterdam Studies of Acute Psychiatry - II (ASAP-II): a comparative study of psychiatric intensive care units in the Netherlands
Background The number of patients in whom mental illness progresses to stages in which acute, and often forced treatment is warranted, is on the increase across Europe. As a consequence, more patients are involuntarily admitted to Psychiatric Intensive Care Units (PICU). From several studies and reports it has become evident that important dissimilarities exist between PICU's. The current study seeks to describe organisational as well as clinical and patient related factors across ten PICU's in and outside the Amsterdam region, adjusted for or stratified by level of urbanization. Method/Design This paper describes the design of the Amsterdam Studies of Acute Psychiatry II (ASAP-II). This study is a prospective observational cohort study comparing PICU's in and outside the Amsterdam region on various patient characteristics, treatment aspects and recovery related variables. Dissimilarities were measured by means of collecting standardized forms which were filled out in the framework of care as usual, by means of questionnaires filled out by mental health care professionals and by means of extracting data from patient files for every consecutive patient admitted at participating PICU's during a specific time period. Urbanization levels for every PICU were calculated conform procedures as proposed by the Dutch Central Bureau for Statistics (CBS). Discussion The current study may provide a deeper understanding of the differences between psychiatric intensive care units that can be used to promote best practice and benchmarking procedures, and thus improve the standard of care
Mediterranean diet or extended fasting's influence on changing the intestinal microflora, immunoglobulin A secretion and clinical outcome in patients with rheumatoid arthritis and fibromyalgia: an observational study
BACKGROUND: Alterations in the intestinal bacterial flora are believed to be contributing factors to many chronic inflammatory and degenerative diseases including rheumatic diseases. While microbiological fecal culture analysis is now increasingly used, little is known about the relationship of changes in intestinal flora, dietary patterns and clinical outcome in specific diseases. To clarify the role of microbiological culture analysis we aimed to evaluate whether in patients with rheumatoid arthritis (RA) or fibromyalgia (FM) a Mediterranean diet or an 8-day fasting period are associated with changes in fecal flora and whether changes in fecal flora are associated with clinical outcome. METHODS: During a two-months-period 51 consecutive patients from an Integrative Medicine hospital department with an established diagnosis of RA (n = 16) or FM (n = 35) were included in the study. According to predefined clinical criteria and the subjects' choice the patients received a mostly vegetarian Mediterranean diet (n = 21; mean age 50.9 +/-13.3 y) or participated in an intermittent modified 8-day fasting therapy (n = 30; mean age 53.7 +/- 9.4 y). Quantitative aerob and anaerob bacterial flora, stool pH and concentrations of secretory immunoglobulin A (sIgA) were analysed from stool samples at the beginning, at the end of the 2-week hospital stay and at a 3-months follow-up. Clinical outcome was assessed with the DAS 28 for RA patients and with a disease severity rating scale in FM patients. RESULTS: We found no significant changes in the fecal bacterial counts following the two dietary interventions within and between groups, nor were significant differences found in the analysis of sIgA and stool ph. Clinical improvement at the end of the hospital stay tended to be greater in fasting vs. non-fasting patients with RA (p = 0.09). Clinical outcome was not related to alterations in the intestinal flora. CONCLUSION: Neither Mediterranean diet nor fasting treatments affect the microbiologically assessed intestinal flora and sIgA levels in patients with RA and FM. The impact of dietary interventions on the human intestinal flora and the role of the fecal flora in rheumatic diseases have to be clarified with newer molecular analysis techniques. The potential benefit of fasting treatment in RA and FM should be further tested in randomised trials
Use of mechanical circulatory support in patients with non-ischaemic cardiogenic shock
Aims Despite its high incidence and mortality risk, there is no evidence-based treatment for non-ischaemic cardiogenic shock (CS). The aim of this study was to evaluate the use of mechanical circulatory support (MCS) for non-ischaemic CS treatment.Methods and results In this multicentre, international, retrospective study, data from 890 patients with non-ischaemic CS, defined as CS due to severe de-novo or acute-on-chronic heart failure with no need for urgent revascularization, treated with or without active MCS, were collected. The association between active MCS use and the primary endpoint of 30-day mortality was assessed in a 1:1 propensity-matched cohort. MCS was used in 386 (43%) patients. Patients treated with MCS presented with more severe CS (37% vs. 23% deteriorating CS, 30% vs. 25% in extremis CS) and had a lower left ventricular ejection fraction at baseline (21% vs. 25%). After matching, 267 patients treated with MCS were compared with 267 patients treated without MCS. In the matched cohort, MCS use was associated with a lower 30-day mortality (hazard ratio 0.76, 95% confidence interval 0.59-0.97). This finding was consistent through all tested subgroups except when CS severity was considered, indicating risk reduction especially in patients with deteriorating CS. However, complications occurred more frequently in patients with MCS; e.g. severe bleeding (16.5% vs. 6.4%) and access-site related ischaemia (6.7% vs. 0%).Conclusion In patients with non-ischaemic CS, MCS use was associated with lower 30-day mortality as compared to medical therapy only, but also with more complications. Randomized trials are needed to validate these findings.[GRAPHICS
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