Exercise-based cardiac rehabilitation improves exercise capacity and health-related quality of life in people with atrial fibrillation: A systematic review and meta-analysis of randomised and non-randomised trials

This is the final version. Available on open access from BMJ Publishing Group via the DOI in this recordObjective The aim of this study was to undertake a contemporary review of the impact of exercise-based cardiac rehabilitation (CR) targeted at patients with atrial fibrillation (AF). Methods We conducted searches of PubMED, EMBASE and the Cochrane Library of Controlled Trials (up until 30 November 2017) using key terms related to exercise-based CR and AF. Randomised and non-randomised controlled trials were included if they compared the effects of an exercise-based CR intervention to a no exercise or usual care control group. Meta-analyses of outcomes were conducted where appropriate. Results The nine randomised trials included 959 (483 exercise-based CR vs 476 controls) patients with various types of AF. Compared with control, pooled analysis showed no difference in all-cause mortality (risk ratio (RR) 1.08, 95% CI 0.77 to 1.53, p=0.64) following exercise-based CR. However, there were improvements in health-related quality of life (mean SF-36 mental component score (MCS): 4.00, 95% CI 0.26 to 7.74; p=0.04 and mean SF-36 physical component score: 1.82, 95% CI 0.06 to 3.59; p=0.04) and exercise capacity (mean peak VO2: 1.59 ml/kg/min, 95% CI 0.11 to 3.08; p=0.04; mean 6 min walk test: 46.9 m, 95% CI 26.4 to 67.4; p<0.001) with exercise-based CR. Improvements were also seen in AF symptom burden and markers of cardiac function. Conclusions Exercise capacity, cardiac function, symptom burden and health-related quality of life were improved with exercise-based CR in the short term (up to 6 months) targeted at patients with AF. However, high-quality multicentre randomised trials are needed to clarify the impact of exercise-based CR on key patient and health system outcomes (including health-related quality of life, mortality, hospitalisation and costs) and how these effects may vary across AF subtypes.National Institute for Health Research (NIHR

What the geological past can tell us about the future of the ocean’s twilight zone

Paleontological reconstructions of plankton community structure during warm periods of the Cenozoic (last 66 million years) reveal that deep-dwelling ‘twilight zone’ (200–1000 m) plankton were less abundant and diverse, and lived much closer to the surface, than in colder, more recent climates. We suggest that this is a consequence of temperature’s role in controlling the rate that sinking organic matter is broken down and metabolized by bacteria, a process that occurs faster at warmer temperatures. In a warmer ocean, a smaller fraction of organic matter reaches the ocean interior, affecting food supply and dissolved oxygen availability at depth. Using an Earth system model that has been evaluated against paleo observations, we illustrate how anthropogenic warming may impact future carbon cycling and twilight zone ecology. Our findings suggest that significant changes are already underway, and without strong emissions mitigation, widespread ecological disruption in the twilight zone is likely by 2100, with effects spanning millennia thereafter

Evaluation of Community-Based Trichiasis Surgery in Northwest Ethiopia

Background: Surgery to correct trachomatous trichiasis (TT) is recommended to prevent blindness caused by trachoma. This study evaluated the outcomes of community-based trichiasis surgery with absorbable sutures, conductd in Amhara Regional State, Ethiopia.Methods: A simple random sample of 431 patients was selected from surgical campaign records of which 363 (84.2%) were traced and enrolled into the study. Participants were interviewed and examined for trichiasis recurrence, complications of TT surgery and corneal opacity. Multilevel logistic regression models were used to explore the associations between trichiasis recurrence, corneal opacity and explanatory variables at the eye level.Results: The prevalence of trichiasis recurrence was 9.4% (95% Confidence Interval [CI] 6.6-12.8) and corneal opacity was found in 14.3% (95% CI 10.9-18.3) of the study participants. The proportion of participants with complications of TT surgery was: granuloma 0.6% (95% CI 0.1-2.0); lid closure defects 5.5% (95% CI 3.4-8.4) and lid notching 16.8% (95% CI 13.1-21.1). No factors were identified for trichiasis recurrence. Corneal opacity was associated with increased age (Ptrend=0.001), more than 12 months post surgery (OR=2.7; 95%CI 1.3-5.6), trichiasis surgery complications (OR=2.9; 95%CI 1.4-5.9) and trichiasis recurrence (OR=2.5; 95%CI 1.0-6.3).Conclusion: Prevalence of recurrent trichiasis and granuloma were lower than expected but higher for lid closure defects and lid notching. The majority of the participants reported satisfaction with the trichiasis surgery they had undergone. The findings suggest that recurrence of trichiasis impacts on the patients’ risk of developing corneal opacity but longitudinal studies are required to confirm this.Keywords: Corneal opacity, Trichiasis, Trichiasis recurrence, Ethiopi

A scalable machine-learning approach to recognize chemical names within large text databases

MOTIVATION: The use or study of chemical compounds permeates almost every scientific field and in each of them, the amount of textual information is growing rapidly. There is a need to accurately identify chemical names within text for a number of informatics efforts such as database curation, report summarization, tagging of named entities and keywords, or the development/curation of reference databases. RESULTS: A first-order Markov Model (MM) was evaluated for its ability to distinguish chemical names from words, yielding ~93% recall in recognizing chemical terms and ~99% precision in rejecting non-chemical terms on smaller test sets. However, because total false-positive events increase with the number of words analyzed, the scalability of name recognition was measured by processing 13.1 million MEDLINE records. The method yielded precision ranges from 54.7% to 100%, depending upon the cutoff score used, averaging 82.7% for approximately 1.05 million putative chemical terms extracted. Extracted chemical terms were analyzed to estimate the number of spelling variants per term, which correlated with the total number of times the chemical name appeared in MEDLINE. This variability in term construction was found to affect both information retrieval and term mapping when using PubMed and Ovid

Australian Enterococcal Sepsis Outcome Programme, 2011

From 1 January to 31 December 2011, 29 institutions around Australia participated in the Australian Enterococcal Sepsis Outcome Programme (AESOP). The aim of AESOP 2011 was to determine the proportion of enterococcal bacteraemia isolates in Australia that are antimicrobial resistant, with particular emphasis on susceptibility to ampicillin and the glycopeptides, and to characterise the molecular epidemiology of the Enterococcus faecalis and E. faecium isolates. Of the 1,079 unique episodes of bacteraemia investigated, 95.8% were caused by either E. faecalis (61.0%) or E. faecium (34.8%). Ampicillin resistance was detected in 90.4% of E. faecium but not detected in E. faecalis. Using Clinical and Laboratory Standards Institute breakpoints (CLSI), vancomycin non-susceptibility was reported in 0.6% and 31.4% of E. faecalis and E. faecium respectively and was predominately due to the acquisition of the vanB operon. Approximately 1 in 6 vanB E. faecium isolates however, had an minimum inhibitory concentration at or below the CLSI vancomycin susceptible breakpoint of &le; 4 mg/L. Overall, 37% of E. faecium harboured vanA or vanB genes. Although molecular typing identified 126 E. faecalis pulsed-field gel electrophoresis (PFGE) pulsotypes, more than 50% belonged to 2 pulsotypes that were isolated across Australia. E. faecium consisted of 73 PFGE pulsotypes from which 43 multilocus sequence types were identified. Almost 90% of the E. faecium were identified as clonal complex 17 clones, of which approximately half were characterised as sequence type 203, which was isolated Australia-wide. In conclusion, the AESOP 2011 has shown that although polyclonal, enterococcal bacteraemias in Australia are frequently caused by ampicillin-resistant vanB E. faecium

Pulse Wave Velocity Measurement in the Carotid Artery Using an LED-LED Array Pulse Oximeter

Pulse wave velocity (PWV) is frequently used as an early indicator of risk of cardiovascular disease. Conventional methods of PWV measurement are invasive and measure the regional PWV, introducing errors from unknown measurement distance to masking local changes in compliance. This paper describes the development and testing of a non-invasive PWV sensor using photoplethysmograph signals. The sensor measures the pulse in the carotid artery with three sensor arrays spaced at 20 mm, 30 mm and 50 mm spacing. Each array of 20 LED-LED sensors are placed at 5 mm to get the largest amplitude pulse across the neck, and to allow for inaccurate sensor placement. LEDs are used as light emitters and the inherent capacitance of reverse biased LEDs measure the reflected light. The foot-foot and phase difference methods were used to calculate the PWV at each measurement distance. The foot-foot method was more reliable than the phase difference at all distances with a PWV of 5.26 m s−1 in a single-subject trial. The sample rate of 570 Hz was deemed too slow as one sample difference resulted in a PWV change of 1.5ms−1. The developed sensor measured the local PWV within the expected physiological range around 6 m s−1. All future measurements will be measured at 1 kHz and an increased LED output intensity

Why Current Statistical Approaches to Ransomware Detection Fail

The frequent use of basic statistical techniques to detect ransomware is a popular and intuitive strategy; statistical tests can be used to identify randomness, which in turn can indicate the presence of encryption and, by extension, a ransomware attack. However, common file formats such as images and compressed data can look random from the perspective of some of these tests. In this work, we investigate the current frequent use of statistical tests in the context of ransomware detection, primarily focusing on false positive rates. The main aim of our work is to show that the current over-dependence on simple statistical tests within anti-ransomware tools can cause serious issues with the reliability and consistency of ransomware detection in the form of frequent false classifications. We determined thresholds for five key statistics frequently used in detecting randomness, namely Shannon entropy, chi-square, arithmetic mean, Monte Carlo estimation for Pi and serial correlation coefficient. We obtained a large data set of 84,327 files comprising of images, compressed data and encrypted data. We then tested these thresholds (taken from a variety of previous publications in the literature where possible) against our dataset, showing that the rate of false positives is far beyond what could be considered acceptable. False positive rates were often above 50% and even above 90% on several occasions. False negative rates were also generally between 5% and 20%, numbers which are also far too high. As a direct result of these experiments, we determine that relying on these simple statistical approaches is not good enough to detect ransomware attacks consistently. We instead recommend the exploration of higher-order statistics such as skewness and kurtosis for future ransomware detection techniques

Advanced magnetic resonance imaging and neuropsychological assessment for detecting brain injury in a prospective cohort of university amateur boxers

$\textbf{Background/aim:}$ The safety of amateur and professional boxing is a contentious issue. We hypothesised that advanced magnetic resonance imaging and neuropsychological testing could provide evidence of acute and early brain injury in amateur boxers. $\textbf{Methods:}$ We recruited 30 participants from a university amateur boxing club in a prospective cohort study. Magnetic resonance imaging (MRI) and neuropsychological testing was performed at three time points: prior to starting training; within 48 hours following a first major competition to detect acute brain injury; and one year follow-up. A single MRI acquisition was made from control participants. Imaging analysis included cortical thickness measurements with Advanced Normalization Tools (ANTS) and FreeSurfer, voxel based morphometry (VBM), and Tract Based Spatial Statistics (TBSS). A computerized battery of neuropsychological tests was performed assessing attention, learning, memory and impulsivity. $\textbf{Results:}$ During the study period, one boxer developed seizures controlled with medication while another developed a chronic subdural hematoma requiring neurosurgical drainage. A total of 10 boxers contributed data at to the longitudinal assessment protocol. Reasons for withdrawal were: logistics (10), stopping boxing (7), withdrawal of consent (2), and development of a chronic subdural hematoma (1). No significant changes were detected using VBM, TBSS, cortical thickness measured with FreeSurfer or ANTS, either cross-sectionally at baseline, or longitudinally. Neuropsychological assessment of boxers found attention/concentration improved over time while planning and problem solving ability latency decreased after a bout but recovered after one year. $\textbf{Conclusion:}$ While this neuroimaging and neuropsychological assessment protocol could not detect any evidence of brain injury, one boxer developed seizures and another developed a chronic sub-dural haematoma.PJH is supported by a NIHR Research Professorship. VFJN is supported by a Health Foundation / Academy of Medical Sciences Clinician Scientist Fellowship. BJS holds a grant from the NIHR Brain Injury Healthcare Technology Co-operative. This study was supported through the Cambridge National Institute for Health Research (NIHR) Biomedical Research Centre (BRC). Control data were acquired with the support of the Medical Research Council as part of their Addiction Initiative (grant number G1000018), and a Pathfinder award from Medical Research Council (G0401099)

Exercise-based cardiac rehabilitation improves exercise capacity and health-related quality of life in people with atrial fibrillation: a systematic review and meta-analysis of randomised and non-randomised trials.

This is the final version. Available on open access from BMJ Publishing Group via the DOI in this recordObjective The aim of this study was to undertake a contemporary review of the impact of exercise-based cardiac rehabilitation (CR) targeted at patients with atrial fibrillation (AF). Methods We conducted searches of PubMED, EMBASE and the Cochrane Library of Controlled Trials (up until 30 November 2017) using key terms related to exercise-based CR and AF. Randomised and non-randomised controlled trials were included if they compared the effects of an exercise-based CR intervention to a no exercise or usual care control group. Meta-analyses of outcomes were conducted where appropriate. Results The nine randomised trials included 959 (483 exercise-based CR vs 476 controls) patients with various types of AF. Compared with control, pooled analysis showed no difference in all-cause mortality (risk ratio (RR) 1.08, 95% CI 0.77 to 1.53, p=0.64) following exercise-based CR. However, there were improvements in health-related quality of life (mean SF-36 mental component score (MCS): 4.00, 95% CI 0.26 to 7.74; p=0.04 and mean SF-36 physical component score: 1.82, 95% CI 0.06 to 3.59; p=0.04) and exercise capacity (mean peak VO2: 1.59 ml/kg/min, 95% CI 0.11 to 3.08; p=0.04; mean 6 min walk test: 46.9 m, 95% CI 26.4 to 67.4; p<0.001) with exercise-based CR. Improvements were also seen in AF symptom burden and markers of cardiac function. Conclusions Exercise capacity, cardiac function, symptom burden and health-related quality of life were improved with exercise-based CR in the short term (up to 6 months) targeted at patients with AF. However, high-quality multicentre randomised trials are needed to clarify the impact of exercise-based CR on key patient and health system outcomes (including health-related quality of life, mortality, hospitalisation and costs) and how these effects may vary across AF subtypes.National Institute for Health Research (NIHR