Physical activity and incidence of atrial fibrillation: A systematic review and meta-analysis

Whether physical activity increases or decreases the risk of atrial fibrillation (AF) remains controversial. We conducted a systematic review and meta-analysis to evaluate the relationship between AF and extent of physical activity. We searched Medline and EMBASE in June 2014 for studies that reported on the associated risk of AF according to history of physical activity. Pooled risk ratios for AF were calculated using inverse variance random effects model, and heterogeneity assessed using I2. Subgroup analysis was performed according to the nature of the physical activity, and the quality of the studies. We identified 19 relevant studies with a total of over half a million participants (n = 511,503). The pooled analysis showed no association between intensive physical activity and AF (RR 1.00 95% CI 0.82–1.22, I2 = 73%, 8 studies, 152,925 participants) with no difference considering low and moderate to high risk of bias studies. Pooled analysis of studies reporting on increasing amount of time spent on physical activities did not show a significant association with AF (RR 0.95 95% CI 0.72–1.26, I2 = 84%, 4 studies, 112,784 participants). Studies of athletes or participants with a history of sports activity which were of poor methodology quality showed a borderline significant association with AF (pooled RR 1.98 95% CI 1.00–3.94, I2 = 59%, 6 studies, 1973 participants). In conclusion, we found no significant increase in AF with a higher level of physical activity. These findings support clinical guidelines encouraging patients to exercise as there is no evidence for harm associated with increased physical activity

The influence of adaptive challenge on engagement of multidisciplinary staff in standardising aseptic technique in an emergency department: A qualitative study

Aims and objectives: To explore the challenge of engaging multidisciplinary staff in standardising aseptic technique (AT) in an emergency department (ED) in an Australian tertiary hospital, and to better understand the enablers and barriers to implementing practice change within this setting. Background: Healthcare‐associated infections are the most common complication for patients in acute care. A clinical practice framework developed in the United Kingdom (UK) standardised AT practice to reduce potential infection risk. One Australian tertiary hospital drew upon this framework to similarly improve clinical practice. It was understood that standardising practice would require some practitioners only to revisit and demonstrate AT principles already embedded in their practice, while others would be challenged to adopt a new approach. Design: Qualitative, descriptive research design. Methods: Data were collected through focus groups held before and after implementation of the AT programme. Data were analysed using the framework method. The (COREQ) checklist was followed. Results: Four emergent themes described the influence of motivation on individuals\u27 beliefs and attitudes towards practice change, relationships within the ED context, delivery of education and management directives. Conclusion: Implementing practice change is more than just providing technical knowledge and includes changing individuals\u27 beliefs and attitudes. An understanding of adaptive challenge can assist in implementing practice change that involves the multidisciplinary team. Relevance to clinical practice: Results provide evidence as to how the adaptive challenge framework could be a suitable approach to manage potential enablers and barriers to implementing change within a multidisciplinary team in an acute hospital

Determining the electronic performance limitations in top-down fabricated Si nanowires with mean widths down to 4 nm

Silicon nanowires have been patterned with mean widths down to 4 nm using top-down lithography and dry etching. Performance-limiting scattering processes have been measured directly which provide new insight into the electronic conduction mechanisms within the nanowires. Results demonstrate a transition from 3-dimensional (3D) to 2D and then 1D as the nanowire mean widths are reduced from 12 to 4 nm. The importance of high quality surface passivation is demonstrated by a lack of significant donor deactivation, resulting in neutral impurity scattering ultimately limiting the electronic performance. The results indicate the important parameters requiring optimization when fabricating nanowires with atomic dimensions

Predicting microbiologically defined infection in febrile neutropenic episodes in children : global individual participant data multivariable meta-analysis

BACKGROUND: Risk-stratified management of fever with neutropenia (FN), allows intensive management of high-risk cases and early discharge of low-risk cases. No single, internationally validated, prediction model of the risk of adverse outcomes exists for children and young people. An individual patient data (IPD) meta-analysis was undertaken to devise one. METHODS: The 'Predicting Infectious Complications in Children with Cancer' (PICNICC) collaboration was formed by parent representatives, international clinical and methodological experts. Univariable and multivariable analyses, using random effects logistic regression, were undertaken to derive and internally validate a risk-prediction model for outcomes of episodes of FN based on clinical and laboratory data at presentation. RESULTS: Data came from 22 different study groups from 15 countries, of 5127 episodes of FN in 3504 patients. There were 1070 episodes in 616 patients from seven studies available for multivariable analysis. Univariable analyses showed associations with microbiologically defined infection (MDI) in many items, including higher temperature, lower white cell counts and acute myeloid leukaemia, but not age. Patients with osteosarcoma/Ewings sarcoma and those with more severe mucositis were associated with a decreased risk of MDI. The predictive model included: malignancy type, temperature, clinically 'severely unwell', haemoglobin, white cell count and absolute monocyte count. It showed moderate discrimination (AUROC 0.723, 95% confidence interval 0.711-0.759) and good calibration (calibration slope 0.95). The model was robust to bootstrap and cross-validation sensitivity analyses. CONCLUSIONS: This new prediction model for risk of MDI appears accurate. It requires prospective studies assessing implementation to assist clinicians and parents/patients in individualised decision making

Independent external validation of a stroke recurrence score in patients with embolic stroke of undetermined source

Abstract Background Embolic stroke of undetermined source (ESUS) accounts for a substantial proportion of ischaemic strokes. A stroke recurrence score has been shown to predict the risk of recurrent stroke in patients with ESUS based on a combination of clinical and imaging features. This study aimed to externally validate the performance of the ESUS recurrence score using data from a randomized controlled trial. Methods The validation dataset consisted of eligible stroke patients with available magnetic resonance imaging (MRI) data enrolled in the PreDAFIS sub-study of the MonDAFIS study. The score was calculated using three variables: age (1 point per decade after 35 years), presence of white matter hyperintensities (2 points), and multiterritorial ischaemic stroke (3 points). Patients were assigned to risk groups as described in the original publication. The model was evaluated using standard discrimination and calibration methods. Results Of the 1054 patients, 241 (22.9%) were classified as ESUS. Owing to insufficient MRI quality, three patients were excluded, leaving 238 patients (median age 65.5 years [IQR 20.75], 39% female) for analysis. Of these, 30 (13%) patients experienced recurrent ischaemic stroke or transient ischemic attack (TIA) during a follow-up period of 383 patient-years, corresponding to an incidence rate of 7.8 per 100 patient-years (95% CI 5.3–11.2). Patients with an ESUS recurrence score value of ≥ 7 had a 2.46 (hazard ratio (HR), 95% CI 1.02–5.93) times higher risk of stroke recurrence than patients with a score of 0–4. The cumulative probability of stroke recurrence in the low-(0–4), intermediate-(5–6), and high-risk group (≥ 7) was 9%, 13%, and 23%, respectively (log-rank test, χ2 = 4.2, p = 0.1). Conclusions This external validation of a published scoring system supports a threshold of ≥ 7 for identifying ESUS patients at high-risk of stroke recurrence. However, further adjustments may be required to improve the model’s performance in independent cohorts. The use of risk scores may be helpful in guiding extended diagnostics and further trials on secondary prevention in patients with ESUS. Trial registration: Clinical Trials, NCT02204267. Registered 30 July 2014, https://clinicaltrials.gov/ct2/show/NCT02204267

First results of the air shower experiment KASCADE

The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment are the determination of the energy spectrum and elemental composition of the charged cosmic rays in the energy range around the knee at ca. 5 PeV. Due to the large number of measured observables per single shower a variety of different approaches are applied to the data, preferably on an event-by-event basis. First results are presented and the influence of the high-energy interaction models underlying the analyses is discussed.Comment: 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings, Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D. Vignau