Switched Linear Model Predictive Controllers for Periodic Exogenous Signals

This paper develops linear switched controllers for periodic exogenous signals using the framework of a continuous-time model predictive control. In this framework, the control signal is generated by an algorithm that uses receding horizon control principle with an on-line optimization scheme that permits inclusion of operational constraints. Unlike traditional repetitive controllers, applying this method in the form of switched linear controllers ensures rumpless transfer from one controller to another. Simulation studies are included to demonstrate the efficacy of the design with or without hard constraints

Design of Marine Protected Areas on high seas and territorial waters of rockall bank

Fisheries closures are rapidly being developed to protect vulnerable marine ecosystems worldwide. Satellite monitoring of fishing vessel activity indicates that these closures can work effectively with good compliance by international fleets even in remote areas. Here we summarise how remote fisheries closures were designed to protect Lophelia pertusa habitat in a region of the NE Atlantic that straddles the EU fishing zone and the high seas. We show how scientific records, fishers' knowledge and surveillance data on fishing activity can be combined to provide a powerful tool for the design of Marine Protected Areas. © Inter-Research 2009

The ecology of seamounts: structure, function, and human impacts.

In this review of seamount ecology, we address a number of key scientific issues concerning the structure and function of benthic communities, human impacts, and seamount management and conservation. We consider whether community composition and diversity differ between seamounts and continental slopes, how important dispersal capabilities are in seamount connectivity, what environmental factors drive species composition and diversity, whether seamounts are centers of enhanced biological productivity, and whether they have unique trophic architecture. We discuss how vulnerable seamount communities are to fishing and mining, and how we can balance exploitation of resources and conservation of habitat. Despite considerable advances in recent years, there remain many questions about seamount ecosystems that need closer integration of molecular, oceanographic, and ecological research

The portion size effect : women demonstrate an awareness of eating more than intended when served larger than normal portions

Large portion sizes lead to increased intake. Some studies suggest that individuals are unaware that they consume more when served larger portions. In a between-subjects design we asked female participants (N = 48) how much pasta and tomato sauce they intended to consume for lunch prior to eating. We then provided a smaller or a larger portion of the same food and invited participants to self-serve a portion into a second bowl (same size in both conditions). After eating until comfortably full, participants were shown an image of the amount they had selected at the beginning of the meal. They were then asked whether they perceived having eaten more or less than this amount, and by how much more or less they had eaten. In total 46 responses were analysed. Of the participants who received the large portion and who ate more than intended, 77% (p = .029) correctly identified eating more. However, when participants were asked to indicate by how much they had eaten above or below their intended amount, those who ate more after receiving a larger portion underestimated their intake by 25% (p = .003). These findings suggest that greater intake from a larger portion is associated with an awareness of having eaten a large quantity combined with a failure to register the actual amount consumed (in the direction of underestimation). The latter might be attributed to an error associated with the visual estimation of volume

Global data for ecology and epidemiology: a novel algorithm for temporal Fourier processing MODIS data

Background. Remotely-sensed environmental data from earth-orbiting satellites are increasingly used to model the distribution and abundance of both plant and animal species, especially those of economic or conservation importance. Time series of data from the MODerate-resolution Imaging Spectroradiometer (MODIS) sensors on-board NASA's Terra and Aqua satellites offer the potential to capture environmental thermal and vegetation seasonality, through temporal Fourier analysis, more accurately than was previously possible using the NOAA Advanced Very High Resolution Radiometer (AVHRR) sensor data. MODIS data are composited over 8- or 16-day time intervals that pose unique problems for temporal Fourier analysis. Applying standard techniques to MODIS data can introduce errors of up to 30% in the estimation of the amplitudes and phases of the Fourier harmonics. Methodology/Principal Findings. We present a novel spline-based algorithm that overcomes the processing problems of composited MODIS data. The algorithm is tested on artificial data generated using randomly selected values of both amplitudes and phases, and provides an accurate estimate of the input variables under all conditions. The algorithm was then applied to produce layers that capture the seasonality in MODIS data for the period from 2001 to 2005. Conclusions/Significance. Global temporal Fourier processed images of 1 km MODIS data for Middle Infrared Reflectance, day- and night-time Land Surface Temperature (LST), Normalised Difference Vegetation Index (NDVI), and Enhanced Vegetation Index (EVI) are presented for ecological and epidemiological applications. The finer spatial and temporal resolution, combined with the greater geolocational and spectral accuracy of the MODIS instruments, compared with previous multi-temporal data sets, mean that these data may be used with greater confidence in species' distribution modelling

Obesity in early adulthood and physical functioning in mid-life: Investigating the mediating role of c-reactive protein

INTRODUCTION: Obesity in adulthood is associated with reduced physical functioning (PF) at older ages. However, mechanisms underpinning this association are not well understood. We investigated whether and the extent to which C-reactive protein (CRP) mediates the association between early-adult obesity and mid-life PF. METHODS: We used data from 8495 participants in the 1958 British birth cohort study. Body mass index (BMI), CRP and PF were measured at 33, 45 and 50y, respectively. Poor PF was defined as the lowest (sex-specific) 10% on the Short-form 36 Physical Functioning subscale. We accounted for prospectively measured confounders in early-life (e.g., social class at birth) and in mid-adulthood (e.g., 42y comorbidities). We decomposed the total effect of early-adult obesity on mid-life PF into direct and indirect (via CRP) effects, by employing a mediation analysis based on parametric g-computation. RESULTS: The estimated total effect of obesity at 33y on poor PF at 50y, expressed as an odds ratio (OR), was 2.41 (95% CI: 1.89, 3.08). The direct effect of obesity on poor PF (i.e., not operating via CRP), was 1.97 (95% CI: 1.51, 2.56), with an indirect effect of 1.23 (95% CI: 1.10, 1.37). As such, the proportion of the total effect which was mediated by the effect of obesity on CRP at 45y, was 23.27% (95% CI: 8.64%, 37.90%). CONCLUSION: Obesity in early-adulthood was associated with over twice the odds of poor PF in mid-life, with approximately 23% of the obesity effect operating via a downstream effect on CRP. As current younger generations are likely to spend greater proportions of their life course in older age and with obesity, both of which are associated with poor PF, there is an urgent need to identify mechanisms, and thus potential modifiable intermediaries, linking obesity to poor PF

What Are the Real Procedural Costs of Bariatric Surgery? A Systematic Literature Review of Published Cost Analyses

This is the final version. Available on open access from Springer Verlag via the DOI in this recordThis review aims to evaluate the current literature on the procedural costs of bariatric surgery for the treatment of severe obesity. Using a published framework for the conduct of micro-costing studies for surgical interventions, existing cost estimates from the literature are assessed for their accuracy, reliability and comprehensiveness based on their consideration of seven ‘important’ cost components. MEDLINE, PubMed, key journals and reference lists of included studies were searched up to January 2017. Eligible studies had to report per-case, total procedural costs for any type of bariatric surgery broken down into two or more individual cost components. A total of 998 citations were screened, of which 13 studies were included for analysis. Included studies were mainly conducted from a US hospital perspective, assessed either gastric bypass or adjustable gastric banding procedures and considered a range of different cost components. The mean total procedural costs for all included studies was US$14,389 (range, US$7423 to US$33,541). No study considered all of the recommended ‘important’ cost components and estimation methods were poorly reported. The accuracy, reliability and comprehensiveness of the existing cost estimates are, therefore, questionable. There is a need for a comparative cost analysis of the different approaches to bariatric surgery, with the most appropriate costing approach identified to be micro-costing methods. Such an analysis will not only be useful in estimating the relative cost-effectiveness of different surgeries but will also ensure appropriate reimbursement and budgeting by healthcare payers to ensure barriers to access this effective treatment by severely obese patients are minimised.National Institute for Health Research (NIHR

Experiences of physical activity: A phenomenological study of individuals with cystic fibrosis

Although extensive research has investigated the benefits of physical activity in cystic fibrosis, minimal exploration of the experiences for individuals from a qualitative, phenomenological perspective has been carried out. The aim of this study was to explore the subjective experiences of physical activity for individuals with cystic fibrosis. The health-care team, at an Adult Cystic Fibrosis Unit in the United Kingdom, recruited 12 participants to take part. Interview data were analysed using interpretative phenomenological analysis. A central theme of ‘self-monitoring’ emerged from the accounts and was embedded in the three super-ordinate themes