Detection of REM Sleep Behaviour Disorder by Automated Polysomnography Analysis

Evidence suggests Rapid-Eye-Movement (REM) Sleep Behaviour Disorder (RBD) is an early predictor of Parkinson's disease. This study proposes a fully-automated framework for RBD detection consisting of automated sleep staging followed by RBD identification. Analysis was assessed using a limited polysomnography montage from 53 participants with RBD and 53 age-matched healthy controls. Sleep stage classification was achieved using a Random Forest (RF) classifier and 156 features extracted from electroencephalogram (EEG), electrooculogram (EOG) and electromyogram (EMG) channels. For RBD detection, a RF classifier was trained combining established techniques to quantify muscle atonia with additional features that incorporate sleep architecture and the EMG fractal exponent. Automated multi-state sleep staging achieved a 0.62 Cohen's Kappa score. RBD detection accuracy improved by 10% to 96% (compared to individual established metrics) when using manually annotated sleep staging. Accuracy remained high (92%) when using automated sleep staging. This study outperforms established metrics and demonstrates that incorporating sleep architecture and sleep stage transitions can benefit RBD detection. This study also achieved automated sleep staging with a level of accuracy comparable to manual annotation. This study validates a tractable, fully-automated, and sensitive pipeline for RBD identification that could be translated to wearable take-home technology.Comment: 20 pages, 3 figure

Diversity, population structure and palaeoecology of the Pleistocene large cervids from the Padang Highlands, Sumatra

This chapter deals with the dentognathic remains of the Late Pleistocene large cervids from the Padang Highlands caves in Sumatra. We used linear and geometric morphometric techniques to investigate variation, taxonomic position and body size trends in a dataset of upper and lower molars. Dental mesowear was used to assess dietary preference in a subsample. The results suggest the Padang Highlands cervids belonged to multiple populations of an early stock of Rusa deer the size of sambar (Rusa unicolor), but morphologically reminiscent of Javan rusa (Rusa timorensis). The Rusa sp. of Sumatra was reconstructed as a mixed feeder with an increase in the grazing component with age

The relevance of spatial variation in ecotourism attributes for the economic sustainability of protected areas

In contemporary society, protected areas are increasingly expected to justify their existence through the services that they provide to society. Protected areas offer many important cultural services, but appraisal of these nonmaterial benefits has generally proven difficult and most studies have focused on single case studies. Data on tourist numbers across multiple camps and protected areas provide a tractable and previously unexploited case study for better understanding the economic sustainability of cultural service provision and the relevance of potentially confounding variables (e.g., location and infrastructure) for park sustainability. We used redundancy analysis and linear models to relate a 5-yr monthly data set (2007–2012) of tourist numbers and tourism-derived income in all camps in South African national parks to a set of largely GIS-derived, determinant attributes that captured key elements of location, biodiversity, infrastructure, and accommodation cost at a camp level. Our analysis suggests that the degree to which cultural services can be converted into revenue for conservation is strongly contingent on infrastructure, location, and the business model that the park adopts. When considered alone, ecological attributes explained 14.2% and 3% of day and overnight visitation rates, respectively. In contrast, models that considered ecosystems in combination with other elements could explain 53% and 67% of variation. Linear models confirmed the existence of complex interactions between groups of variables and highlighted individual covariates that affected visitation rates. Significant variables included ecological features that provided aesthetic services, number of water bodies, elevation, available units, unit costs, and distance to the coast, airports, and other national parks. Taken in context our results suggest that it may be simpler than expected to make predictions about the potential future economic viability of protected areas under alternative models of management, illustrate how ecological variables may represent the “supply” side in cultural services, and highlight the complex interplay between ecological and built infrastructure. Encouragingly, this in turn suggests that relatively small, targeted investments in infrastructure could lead to disproportionate increases in tourist visitation rates and hence in increased revenue for conservation

Time, Incompleteness and Singularity in Quantum Cosmology

In this paper we extend our 2007 paper, Comparative Quantum Cosmology: Causality, Singularity, and Boundary Conditions, arXiv:0710.5046 to include consideration of universal expansion, various implications of extendibility and incompleteness in spacetime metrics and, absent the treatment of Feynman diagrams, the use of Penning trap dynamics as explained by Ferdandez and Velazquez to describe the Hamiltonians of space-times with no characteristic upper or lower bound and to compare the above with Peter Lynds' conjecture on the specialness of initial conditions in inflationary theory in quantum cosmology.Comment: 14 Pages. Complex 2009. The First International Conference on Complex Sciences: Theory and Applications, Shanghai China, February 23-25, 200

Automated Movement Detection with Dirichlet Process Mixture Models and Electromyography

Numerous sleep disorders are characterised by movement during sleep, these include rapid-eye movement sleep behaviour disorder (RBD) and periodic limb movement disorder. The process of diagnosing movement related sleep disorders requires laborious and time-consuming visual analysis of sleep recordings. This process involves sleep clinicians visually inspecting electromyogram (EMG) signals to identify abnormal movements. The distribution of characteristics that represent movement can be diverse and varied, ranging from brief moments of tensing to violent outbursts. This study proposes a framework for automated limb-movement detection by fusing data from two EMG sensors (from the left and right limb) through a Dirichlet process mixture model. Several features are extracted from 10 second mini-epochs, where each mini-epoch has been classified as 'leg-movement' or 'no leg-movement' based on annotations of movement from sleep clinicians. The distributions of the features from each category can be estimated accurately using Gaussian mixture models with the Dirichlet process as a prior. The available dataset includes 36 participants that have all been diagnosed with RBD. The performance of this framework was evaluated by a 10-fold cross validation scheme (participant independent). The study was compared to a random forest model and outperformed it with a mean accuracy, sensitivity, and specificity of 94\%, 48\%, and 95\%, respectively. These results demonstrate the ability of this framework to automate the detection of limb movement for the potential application of assisting clinical diagnosis and decision-making

Structural and photophysical characterisation of coordination and optical isomers of mononuclear ruthenium(II) polypyridyl 1,2,4-triazole complexes

The X-ray crystal structure of the N2 isomers of the Ru(bipy)2 complexes of Hphpztr (1) and Hpztr (2), (bipy = 2,2'-bipyridine, Hphpztr = 2-(5'-phenyl-4'H-[1,2,4]triazol-3'-yl)pyrazine and Hpztr = 2-(4'H-[1,2,4]triazol-3'-yl)pyrazine) are reported. The molecular structure obtained for 2 demonstrates an interesting structural aspect in the sharing of a single proton between two molecular units. The isolation of the Δ and Λ stereoisomers of 1 and [Ru(phen)2(pztr)]+ (phen = 1,10-phenanthroline) (3) by semipreparative HPLC is also reported. The compounds obtained are characterised by electronic spectroscopy and particular attention is paid to the photophysical properties of Δ and Λ isomers of 1 and 3, in chiral enantiopure and racemic solvents

Microbial diversity studies of the porcine gastrointestinal ecosystem during weaning transition

At the time of weaning, major quantitative and qualitative changes occur in the composition of the intestinal microbiota of piglets, influenced by diet, environmental factors, and the host. Within a short period of time, the intestinal microbiota must ultimately develop from a simple, unstable community into a complex and stable one. Here we present data on the development of the intestinal microbiota based on 16S rRNA gene sequence diversity. In addition to a PCR-based analysis of the 16S rRNA gene by cloning and denaturing gradient gel electrophoresis (DGGE), data on fluorescent in situ hybridisation (FISH) are presented to quantify the total bacterial communities, major Lactobacillus populations and specific Lactobacillus species. The results reported here indicate that the addition of non-digestible, fermentable carbohydrates (= prebiotics) leads to an enrichment of lactobacilli in the small intestine, and increased stability and diversity of the bacterial community in the colon. The data support the hypothesis that changes of the diet can modulate the composition of the microbiota in the intestine. These findings may have potentially major implications for the development of dietary strategies aiming to improve animal health during the weaning process