Joint disease mapping using six cancers in the Yorkshire region of England

OBJECTIVES: The aims of this study were to model jointly the incidence rates of six smoking related cancers in the Yorkshire region of England, to explore the patterns of spatial correlation amongst them, and to estimate the relative weight of smoking and other shared risk factors for the relevant disease sites, both before and after adjustment for socioeconomic background (SEB). METHODS: Data on the incidence of oesophagus, stomach, pancreas, lung, kidney, and bladder cancers between 1983 and 2003 were extracted from the Northern & Yorkshire Cancer Registry database for the 532 electoral wards in the Yorkshire region. Using postcode of residence, each case was assigned an area-based measure of SEB using the Townsend index. Standardised incidence ratios (SIRs) were calculated for each cancer site and their correlations investigated. The joint analysis of the spatial variation in incidence used a Bayesian shared-component model. Three components were included to represent differences in smoking (for all six sites), bodyweight/obesity (for oesophagus, pancreas and kidney cancers) and diet/alcohol consumption (for oesophagus and stomach cancers). RESULTS: The incidence of cancers of the oesophagus, pancreas, kidney, and bladder was relatively evenly distributed across the region. The incidence of stomach and lung cancers was more clustered around the urban areas in the south of the region, and these two cancers were significantly associated with higher levels of area deprivation. The incidence of lung cancer was most impacted by adjustment for SEB, with the rural/urban split becoming less apparent. The component representing smoking had a larger effect on cancer incidence in the eastern part of the region. The effects of the other two components were small and disappeared after adjustment for SEB. CONCLUSIONS: This study demonstrates the feasibility of joint disease modelling using data from six cancer sites. Incidence estimates are more precise than those obtained without smoothing. This methodology may be an important tool to help authorities evaluate healthcare system performance and the impact of policies

TOPSIS-RTCID for range target-based criteria and interval data

[EN] The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is receiving considerable attention as an essential decision analysis technique and becoming a leading method. This paper describes a new version of TOPSIS with interval data and capability to deal with all types of criteria. An improved structure of the TOPSIS is presented to deal with high uncertainty in engineering and engineering decision-making. The proposed Range Target-based Criteria and Interval Data model of TOPSIS (TOPSIS-RTCID) achieves the core contribution in decision making theories through a distinct normalization formula for cost and benefits criteria in scale of point and range target-based values. It is important to notice a very interesting property of the proposed normalization formula being opposite to the usual one. This property can explain why the rank reversal problem is limited. The applicability of the proposed TOPSIS-RTCID method is examined with several empirical litreture’s examples with comparisons, sensitivity analysis, and simulation. The authors have developed a new tool with more efficient, reliable and robust outcomes compared to that from other available tools. The complexity of an engineering design decision problem can be resolved through the development of a well-structured decision making method with multiple attributes. Various decision approches developed for engineering design have neglected elements that should have been taken into account. Through this study, engineering design problems can be resolved with greater reliability and confidence.Jahan, A.; Yazdani, M.; Edwards, K. (2021). TOPSIS-RTCID for range target-based criteria and interval data. International Journal of Production Management and Engineering. 9(1):1-14. https://doi.org/10.4995/ijpme.2021.13323OJS11491Ahn, B.S. (2017). 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Developing WASPAS-RTB method for range target-based criteria: toward selection for robust design. Technological and Economic Development of Economy, 24, 1362-1387. https://doi.org/10.3846/20294913.2017.1295288Jahan, A., Bahraminasab, M., Edwards, K.L. (2012). A target-based normalization technique for materials selection. Materials & Design, 35, 647-654. https://doi.org/10.1016/j.matdes.2011.09.005Jahan, A., Edwards, K.L. (2013). VIKOR method for material selection problems with interval numbers and target-based criteria. Materials & Design, 47, 759-765. https://doi.org/10.1016/j.matdes.2012.12.072Jahan, A., Edwards, K.L. (2015). A state-of-the-art survey on the influence of normalization techniques in ranking: Improving the materials selection process in engineering design. Materials & Design, 65, 335-342. https://doi.org/10.1016/j.matdes.2014.09.022Jahan, A., Edwards, K.L., Bahraminasab, M. (2016). Multi-criteria decision analysis for supporting the selection of engineering materials in product design, Oxford, Butterworth-Heinemann.Jahan, A., Mustapha, F., Ismail, M.Y., Sapuan, S.M., Bahraminasab, M. (2011). A comprehensive VIKOR method for material selection. Materials & Design, 32, 1215-1221. https://doi.org/10.1016/j.matdes.2010.10.015Jahan, A., Zavadskas, E.K. (2018). ELECTRE-IDAT for design decision-making problems with interval data and target-based criteria. Soft Computing, 23, 129-143. https://doi.org/10.1007/s00500-018-3501-6Jahanshahloo, G.R., Hosseinzadeh Lotfi, F., Davoodi, A.R. (2009). Extension of TOPSIS for decision-making problems with interval data: Interval efficiency. Mathematical and Computer Modelling, 49, 1137-1142. https://doi.org/10.1016/j.mcm.2008.07.009Jahanshahloo, G.R., Lotfi, F.H., Izadikhah, M. (2006). An algorithmic method to extend TOPSIS for decision-making problems with interval data. 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Do smokers have greater risk of delayed and non-union after fracture, osteotomy and arthrodesis?: a systematic review with meta-analysis

Objectives: Systematic review and meta-analysis of published observational cohort studies. To quantify the increased risk smokers have of experiencing a delayed and/or non-union in fractures, spinal fusion, osteotomy, arthrodesis or established non-unions. Setting: Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE), Allied and Complementary Medicine Database (AMED) and Web of Science Core Collection from 1966 to 2015. Study eligibility criteria, participants and interventions: Observational cohort studies that reported adult smokers and non-smokers with delayed and/or non-union or time to union of the fracture, spinal fusion, osteotomy, arthrodesis or established non-union were eligible. Data extraction and outcome measures: 2 authors screen titles, abstracts and full papers. Data were extracted by 1 author and checked independently by a second. The relative risk ratios of smoking versus non-smoking and the mean difference in time to union patients developing a delayed and/or non-union were calculated. Results: The search identified 3013 articles; of which, 40 studies were included. The meta-analysis of 7516 procedures revealed that smoking is linked to an increased risk of delayed and/or non-union. When considered collectively, smokers have 2.2 (1.9 to 2.6) times the risk of experiencing delayed and/or non-union. In all the subgroups, the increased risk was always ≥1.6 times that of non-smokers. In the patients where union did occur, it was a longer process in the smokers. The data from 923 procedures were included and revealed an increase in time to union of 27.7 days (14.2 to 41.3). Conclusions: Smokers have twice the risk of experiencing a non-union after fracture, spinal fusion, osteotomy, arthrodesis or treatment of non-union. Time to union following fracture, osteotomy, arthrodesis or treatment of an established non-union is longer in smokers. Smokers should be encouraged to abstain from smoking to improve the outcome of these orthopaedic treatments

A mixed methods study of knee confidence and self-efficacy: perceptions of knee osteoarthritis patients from the good life with osteoarthritis in Denmark initiative

Purpose: The Good Life with osteoArthritis in Denmark (GLA:D) Initiative is an evidence-based treatment programme for patients with knee and hip osteoarthritis (OA). It incorporates training physiotherapists to deliver care in accordance with the clinical guidelines by educating patients on their condition and by delivering supervised neuromuscular exercises to relieve pain and improve function. The importance of self-efficacy, and confidence in exercise, to exercise adherence has not been reported for the GLA:D population. In addition, worse knee confidence in people with knee OA is associated with higher pain and greater perceived knee instability. The aims of this study were to investigate the association between knee confidence and self-efficacy in patients with knee OA in the GLA:D registry; and to explore patients’ perception of their experiences with the GLA:D programme, and whether confidence and self-efficacy has a role to play in continuing with the GLA:D exercises in the long-term. Methods: This study used a mixed methods design. Patients with knee OA who were offered at least two educational sessions and six weeks of GLA:D exercise programme between January–March 2015 were identified from the GLA:D registry (n = 484) and sent an online survey. Ordinal regression analyses were performed. Knee confidence, assessed using the Knee injury and Osteoarthritis Outcomes Score (KOOS; quality of life subscale, question 3), was the dependent variable and self-reported measures for exercise self-efficacy; arthritis self-efficacy; multidimensional outcomes expectations for exercise; and KOOS pain and activities of daily living (ADL) were the independent variables. Knee confidence score ranged from 0–4 with 0 indicating higher knee confidence. The independent variables ranged from 0–10 or 0–100 with 0 indicating worse symptoms or confidence. Subsequently, semi-structured interviews (n = 4) were used to explore patients’ perceived confidence and adherence to the GLA:D exercises. Interviews were transcribed verbatim, and analysed using interpretative phenomenological analysis. Results: 200 patients (41.3%) responded to the survey. At 7–10 months following treatment initiation, 9.5% of patients were not at all troubled by lack of knee confidence; 39.5% were mildly troubled; 31.5% were moderately troubled; 15.5% were severely troubled; and 4% were extremely troubled. Patients with higher arthritis self-efficacy score were more likely to have higher knee confidence (odds ratio [OR] = 0.76; 95% confidence interval [CI] 0.63, 0.93; P = 0.007). Patients with higher KOOS ADL score were more likely to have higher knee confidence, although this association was small (OR = 0.96; 95% CI 0.93, 0.99; P = 0.006). No association was found between knee confidence and exercise self-efficacy (OR = 1.00; 95% CI 0.99, 1.01; P = 0.90). Patients reflected on seeing great improvements in their confidence, pain and mobility with the programme. They felt their symptoms got worse if they did not keep up with the exercises. Patients reflected on the importance of continued contact with their physiotherapist after the 6-week programme for further motivation and reassurance. One of the barriers that discouraged patients from continuing with the exercises in the long-term was the cost for additional GLA:D exercise classes with their physiotherapist. Conclusions: Patients are troubled by the lack of knee confidence after the GLA:D exercise programme; they reflected this was due to their negative experiences prior to entering the GLA:D programme. Arthritis self-efficacy and KOOS ADL were significantly associated with knee confidence, but no association was found with exercise self-efficacy. Patients from the interview reflected that maintaining contact with their physiotherapist was an important factor to motivate them to continue exercising

Quantifying carbon stocks in shifting cultivation landscapes under divergent management scenarios relevant to REDD+

Shifting cultivation dominates many tropical forest regions. It is expanding into old-growth forests, and fallow period duration is rapidly decreasing, limiting secondary forest recovery. Shifting cultivation is thus a major driver of carbon emissions through deforestation and forest degradation, and of biodiversity loss. The impacts of shifting cultivation on carbon stocks have rarely been quantified, and the potential for carbon-based payments for ecosystem services (PES), such as REDD+, to protect carbon in shifting cultivation landscapes is unknown. We present empirical data on aboveground carbon stocks in old-growth forest and shifting cultivation landscapes in northeast India, a hotspot of threatened biodiversity. We then model landscape-level carbon stocks under business-as-usual scenarios, via expansion into the old-growth forest or decreasing fallow periods, and intervention scenarios in which REDD+ is used to either reduce deforestation of primary or secondary forest or increase fallow period duration. We found substantial recovery of carbon stocks as secondary forest regenerates, with a 30-yr fallow storing about one-half the carbon of an old-growth forest. Business-as-usual scenarios led to substantial carbon loss, with an 80% reduction following conversion of old-growth forest to a 30-yr shifting cultivation cycle and, relative to a 30-yr cultivation landscape, a 70% reduction when switching to a 5-yr cultivation cycle. Sparing old-growth forests from deforestation using protected areas and intensifying cropping in the remaining area of shifting cultivation is the most optimal strategy for carbon storage. In areas lacking old-growth forest, substantial carbon stocks accumulate over time by sparing fallows for permanent forest regeneration. Successful implementation of REDD+ in shifting cultivation landscapes can help avert global climate change by protecting forest carbon, with likely co-benefits for biodiversity

Physical activity and sedentary behaviour in 12-13 year old children, stratified by sex, school type and residential deprivation score

Many children are insufficiently active for good health. Factors affecting childhood physical activity and sedentary behaviour levels have been identified, including residential and school factors. Three schools in Sheffield, UK were recruited. Data were collected from children aged 12-13 years on their physical activity and sedentary behaviours using the Youth Physical Activity Questionnaire. Data were analysed using univariate (t-test), non-parametric (X2, Krusall Wallis), and regression models adjusted for school type, sex and residential deprivation score. Children (n=189) attending the independent schools had higher MVPA levels (p<0.008; 95% CI 348-2289 extra minutes per week), and were more likely to meet the physical activity guidelines; this association was particularly strong for boys (boys at independent schools 7.8x more likely). Sex and residential deprivation score were not statistically significantly associated with MVPA or meeting physical activity guidelines. Children in affluent areas had the highest sedentary behaviour levels (p=0.021; 95% CI -1171 to -98). School type and sex were not statistically significantly associated with sedentary behaviour, after adjusting for the other factors. This study found that independent school children, particularly boys, were more active across the whole day, when compared with their state school counterparts. They were also more likely to meet the government’s physical activity guidelines. There was no significant difference in the amount of time girls and boys spent in sedentary activities, but the types of sedentary activity differed between sexes. Children from less deprived areas reported more time spent in sedentary activities

Compaction of Rods: Relaxation and Ordering in Vibrated, Anisotropic Granular Material

We report on experiments to measure the temporal and spatial evolution of packing arrangements of anisotropic, cylindrical granular material, using high-resolution capacitive monitoring. In these experiments, the particle configurations start from an initially disordered, low-packing-fraction state and under vertical vibrations evolve to a dense, highly ordered, nematic state in which the long particle axes align with the vertical tube walls. We find that the orientational ordering process is reflected in a characteristic, steep rise in the local packing fraction. At any given height inside the packing, the ordering is initiated at the container walls and proceeds inward. We explore the evolution of the local as well as the height-averaged packing fraction as a function of vibration parameters and compare our results to relaxation experiments conducted on spherically shaped granular materials.Comment: 9 pages incl. 7 figure

Cohort profile: The Trivandrum Non-alcoholic Fatty Liver Disease (NAFLD) Cohort

Purpose The Trivandrum NAFLD cohort is a population-based study designed to examine the interaction between genetic and lifestyle factors and their association with increased risk of NAFLD within the Indian population. Participants Between 2013 and 2016, 2222 participants were recruited to this cohort through multi-stage cluster sampling across the whole population of Trivandrum – a district within the state of Kerala, South India. Data was collected from all inhabitants of randomly-selected households over the age of 25. Findings to date Full baseline clinical and pathological data was collected from 2158 participants. This included detailed demographic profiles, anthropometric measures and lifestyle data (food frequency, physical activity and anxiety and depression questionnaires). Biochemical profile and ultrasound assessment of the liver were performed and whole blood aliquots were collected for DNA analysis. The NAFLD prevalence within this population was 49.8% which is significantly higher than the global pooled prevalence of 25%. This highlights the importance of robust, prospective studies like this to enable collection of longitudinal data on risk factors, disease progression and to facilitate future interventional studies. Future plans The complete analysis of data collected from this cohort will give valuable insights into the interaction of the phenotypic and genotypic profiles that result in such a dramatic increased risk of NAFLD within the Indian population. The cohort will also form the basis of future lifestyle interventional studies, aimed at improving liver and metabolic health

A microscopic 2D lattice model of dimer granular compaction with friction

We study by Monte Carlo simulation the compaction dynamics of hard dimers in 2D under the action of gravity, subjected to vertical and horizontal shaking, considering also the case in which a friction force acts for horizontal displacements of the dimers. These forces are modeled by introducing effective probabilities for all kinds of moves of the particles. We analyze the dynamics for different values of the time $\tau$ during which the shaking is applied to the system and for different intensities of the forces. It turns out that the density evolution in time follows a stretched exponential behavior if $\tau$ is not very large, while a power law tail develops for larger values of $\tau$. Moreover, in the absence of friction, a critical value $\tau^*$ exists which signals the crossover between two different regimes: for $\tau < \tau^*$ the asymptotic density scales with a power law of $\tau$, while for $\tau > \tau^*$ it reaches logarithmically a maximal saturation value. Such behavior smears out when a finite friction force is present. In this situation the dynamics is slower and lower asymptotic densities are attained. In particular, for significant friction forces, the final density decreases linearly with the friction coefficient. We also compare the frictionless single tap dynamics to the sequential tapping dynamics, observing in the latter case an inverse logarithmic behavior of the density evolution, as found in the experiments.Comment: 10 pages, 15 figures, to be published in Phys. Rev.

Phenomenological glass model for vibratory granular compaction

A model for weakly excited granular media is derived by combining the free volume argument of Nowak et al. [Phys. Rev. E 57, 1971 (1998)] and the phenomenological model for supercooled liquids of Adam and Gibbs [J. Chem. Phys. 43, 139 (1965)]. This is made possible by relating the granular excitation parameter \Gamma, defined as the peak acceleration of the driving pulse scaled by gravity, to a temperature-like parameter \eta(\Gamma). The resulting master equation is formally identical to that of Bouchaud's trap model for glasses [J. Phys. I 2, 1705 (1992)]. Analytic and simulation results are shown to compare favourably with a range of known experimental behaviour. This includes the logarithmic densification and power spectrum of fluctuations under constant \eta, the annealing curve when \eta is varied cyclically in time, and memory effects observed for a discontinuous shift in \eta. Finally, we discuss the physical interpretation of the model parameters and suggest further experiments for this class of systems.Comment: 2 references added; some figure labels tweaked. To appear in PR