11 x 11 Domineering is Solved: The first player wins

We have developed a program called MUDoS (Maastricht University Domineering Solver) that solves Domineering positions in a very efficient way. This enables the solution of known positions so far (up to the 10 x 10 board) much quicker (measured in number of investigated nodes). More importantly, it enables the solution of the 11 x 11 Domineering board, a board up till now far out of reach of previous Domineering solvers. The solution needed the investigation of 259,689,994,008 nodes, using almost half a year of computation time on a single simple desktop computer. The results show that under optimal play the first player wins the 11 x 11 Domineering game, irrespective if Vertical or Horizontal starts the game. In addition, several other boards hitherto unsolved were solved. Using the convention that Vertical starts, the 8 x 15, 11 x 9, 12 x 8, 12 x 15, 14 x 8, and 17 x 6 boards are all won by Vertical, whereas the 6 x 17, 8 x 12, 9 x 11, and 11 x 10 boards are all won by Horizontal

Is computer aided detection (CAD) cost effective in screening mammography? A model based on the CADET II study

BACKGROUND: Single reading with computer aided detection (CAD) is an alternative to double reading for detecting cancer in screening mammograms. The aim of this study is to investigate whether the use of a single reader with CAD is more cost-effective than double reading. METHODS: Based on data from the CADET II study, the cost-effectiveness of single reading with CAD versus double reading was measured in terms of cost per cancer detected. Cost (Pound (£), year 2007/08) of single reading with CAD versus double reading was estimated assuming a health and social service perspective and a 7 year time horizon. As the equipment cost varies according to the unit size a separate analysis was conducted for high, average and low volume screening units. One-way sensitivity analyses were performed by varying the reading time, equipment and assessment cost, recall rate and reader qualification. RESULTS: CAD is cost increasing for all sizes of screening unit. The introduction of CAD is cost-increasing compared to double reading because the cost of CAD equipment, staff training and the higher assessment cost associated with CAD are greater than the saving in reading costs. The introduction of single reading with CAD, in place of double reading, would produce an additional cost of £227 and £253 per 1,000 women screened in high and average volume units respectively. In low volume screening units, the high cost of purchasing the equipment will results in an additional cost of £590 per 1,000 women screened.One-way sensitivity analysis showed that the factors having the greatest effect on the cost-effectiveness of CAD with single reading compared with double reading were the reading time and the reader's professional qualification (radiologist versus advanced practitioner). CONCLUSIONS: Without improvements in CAD effectiveness (e.g. a decrease in the recall rate) CAD is unlikely to be a cost effective alternative to double reading for mammography screening in UK. This study provides updated estimates of CAD costs in a full-field digital system and assessment cost for women who are re-called after initial screening. However, the model is highly sensitive to various parameters e.g. reading time, reader qualification, and equipment cost

Radical genome remodelling accompanied the emergence of a novel host-restricted bacterial pathogen

The emergence of new pathogens is a major threat to public and veterinary health. Changes in bacterial habitat such as a switch in host or disease tropism are typically accompanied by genetic diversification. Staphylococcus aureus is a multi-host bacterial species associated with human and livestock infections. A microaerophilic subspecies, Staphylococcus aureus subsp. anaerobius, is responsible for Morel’s disease, a lymphadenitis restricted to sheep and goats. However, the evolutionary history of S. aureus subsp. anaerobius and its relatedness to S. aureus are unknown. Population genomic analyses of clinical S. aureus subsp. anaerobius isolates revealed a highly conserved clone that descended from a S. aureus progenitor about 1000 years ago before differentiating into distinct lineages that contain African and European isolates. S. aureus subsp. anaerobius has undergone limited clonal expansion, with a restricted population size, and an evolutionary rate 10-fold slower than S. aureus. The transition to its current restricted ecological niche involved acquisition of a pathogenicity island encoding a ruminant host-specific effector of abscess formation, large chromosomal re-arrangements, and the accumulation of at least 205 pseudogenes, resulting in a highly fastidious metabolism. Importantly, expansion of ~87 insertion sequences (IS) located largely in intergenic regions provided distinct mechanisms for the control of expression of flanking genes, including a novel mechanism associated with IS-mediated anti-anti-sense decoupling of ancestral gene repression. Our findings reveal the remarkable evolutionary trajectory of a host-restricted bacterial pathogen that resulted from extensive remodelling of the S. aureus genome through an array of diverse mechanisms in parallel

Health state utilities in patients with diabetic retinopathy, diabetic macular oedema and age-related macular degeneration: a systematic review

Background Health state utility values (HSUVs) are important in the assessment of the cost effectiveness of new interventions. In the case of visual conditions, models generally tend have tended to be built around a set of health states defined by visual acuity (VA). The aim of this review was to assess the impact of VA on HSUVs in patients with diabetic retinopathy, diabetic macular oedema or age-related macular degeneration. Methods A systematic literature search was undertaken in major bibliographic databases to identify articles reporting on the relationship between HSUVs and vision. Data were extracted for population characteristics, visual levels and estimated utilities. Evidence from reported statistical models, where available, was considered in the evaluation of vision in the better-seeing eye and the worse-seeing eye. Due to the heterogeneity of included studies, a narrative synthesis was undertaken. Results Of the 17 relevant studies, 9 studies had data that could be used in the analysis of the impact of vision on HSUVs. Visual loss was associated with a marked impact on health utilities. However, the relationship was not comparable between conditions or by measure of HSUVs. Key results included the finding that overall, self-rated time-trade off estimates were more likely to discriminate between different VA levels than EQ-5D values. Additionally, a stronger correlation was observed between HSUVs and better-seeing eye VA compared to worse-seeing eye VA. Conclusions Visual acuity has a significant impact on HSUVs. Nevertheless, care must be taken in the interpretation and use of estimates in cost-effectiveness models due to differences in measures and population diversity

The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

Environments for Healthy Living (EFHL) Griffith birth cohort study: background and methods

The health of an individual is determined by the interaction of genetic and individual factors with wider social and environmental elements. Public health approaches to improving the health of disadvantaged populations will be most effective if they optimise influences at each of these levels, particularly in the early part of the life course. In order to better ascertain the relative contribution of these multi-level determinants there is a need for robust studies, longitudinal and prospective in nature, that examine individual, familial, social and environmental exposures. This paper describes the study background and methods, as it has been implemented in an Australian birth cohort study, Environments for Healthy Living (EFHL): The Griffith Study of Population Health. EFHL is a prospective, multi-level, multi-year longitudinal birth cohort study, designed to collect information from before birth through to adulthood across a spectrum of eco-epidemiological factors, including genetic material from cord-blood samples at birth, individual and familial factors, to spatial data on the living environment. EFHL commenced the pilot phase of recruitment in 2006 and open recruitment in 2007, with a target sample size of 4000 mother/infant dyads. Detailed information on each participant is obtained at birth, 12-months, 3-years, 5-years and subsequent three to five yearly intervals. The findings of this research will provide detailed evidence on the relative contribution of multi-level determinants of health, which can be used to inform social policy and intervention strategies that will facilitate healthy behaviours and choices across sub-populations