Wearable-based assessment of heart rate response to physical stressors in patients after open-heart surgery with frailty

Due to frailty, cardiac rehabilitation in older patients after open-heart surgery must be carefully tailored, thus calling for informative and convenient tools to assess the effectiveness of exercise training programs. The study investigates whether heart rate (HR) response to daily physical stressors can provide useful information when parameters are estimated using a wearable device. The study included 100 patients after open-heart surgery with frailty who were assigned to intervention and control groups. Both groups attended inpatient cardiac rehabilitation however only the patients of the intervention group performed exercises at home according to the tailored exercise training program. While performing maximal veloergometry test and submaximal tests, i.e., walking, stair-climbing, and stand up and go, HR response parameters were derived from a wearable-based electrocardiogram. All submaximal tests showed moderate to high correlation ( r = 0.59–0.72) with veloergometry for HR recovery and HR reserve parameters. While the effect of inpatient rehabilitation was only reflected by HR response to veloergometry, parameter trends over the entire exercise training program were also well followed during stair-climbing and walking. Based on study findings, HR response to walking should be considered for assessing the effectiveness of home-based exercise training programs in patients with frailty

Managing transport challenges when oil prices rise

This report provides practical guidance to central, regional, and local government agencies on how to manage the transport challenges associated with rising oil prices. The three main sections of the report are: • Modelling Prices for Transport Fuels – several oil price forecasts are combined to develop a view on future oil prices. This shows annual average oil prices staying around $110 USD/barrel in 2008, before accelerating rapidly to reach approximately$150 USD/barrel in 2012. After this point prices may stabilise or even decline. Retail prices for petrol and diesel are expected to peak at approximately $2.80 and$2.50 NZD/litre respectively in 2011. Upside and downside risks to these price forecasts exist, particularly in relation to economic growth. • Modelling Future Travel Demands - travel demand elasticities and cross-elasticities are used to model future travel demands. This considered the effects of fuel prices, economic growth, vehicle ownership, workforce participation, and disposable income on vehicle kilometres travelled (VKT). Under the average fuel price scenario total VKT falls below current levels until approximately 2016, after which the combined effects of economic growth, increases in income, and population growth become dominant. • Responses to Rising Oil Prices – a range of responses are identified in the areas of land use management, direct and efficient pricing, infrastructure management, behaviour change and education, and freight management. These responses are cumulatively expected to shift travel demands from passenger vehicles to alternative modes, such that total VKT remains at or below current levels. It is recommended that the focus of infrastructure investment shift from peak hour capacity expansion and instead prioritise investment in road network maintenance and alternative transport modes. Both these measures are likely to deliver a transport system that is more energy efficient, as well as realising a range of wider economic benefits

Rationally seeded computational protein design of ɑ-helical barrels

Computational protein design is advancing rapidly. Here we describe efficient routes starting from validated parallel and antiparallel peptide assemblies to design two families of α-helical barrel proteins with central channels that bind small molecules. Computational designs are seeded by the sequences and structures of defined de novo oligomeric barrel-forming peptides, and adjacent helices are connected by loop building. For targets with antiparallel helices, short loops are sufficient. However, targets with parallel helices require longer connectors; namely, an outer layer of helix–turn–helix–turn–helix motifs that are packed onto the barrels. Throughout these computational pipelines, residues that define open states of the barrels are maintained. This minimizes sequence sampling, accelerating the design process. For each of six targets, just two to six synthetic genes are made for expression in Escherichia coli. On average, 70% of these genes express to give soluble monomeric proteins that are fully characterized, including high-resolution structures for most targets that match the design models with high accuracy

Detection of occult paroxysmal atrial fibrillation

This work introduces a novel approach to the detection of brief episodes of paroxysmal atrial fibrillation (PAF). The proposed detector is based on four parameters which characterize RR interval irregularity, P-wave absence, f-wave presence, and noise level, of which the latter three are determined from a signal produced by an echo state network. The parameters are used for fuzzy logic classification where the decisions involve information on prevailing signal quality; no training is required. The performance is evaluated on a large set of test signals with brief episodes of PAF. The results show that episodes with as few as five beats can be reliably detected with an accuracy of 0.88, compared to 0.82 for a detector based on rhythm information only (the coefficient of sample entropy); this difference in accuracy increases when atrial premature beats are present. The results also show that the performance remains essentially unchanged at noise levels up to RMS. It is concluded that the combination of information on ventricular activity, atrial activity, and noise leads to substantial improvement when detecting brief episodes of PAF