Potential of derived lunar volatiles for life support

The lunar regolith contains small quantities of solar wind implanted volatile compounds that have vital, basic uses for maintaining life support systems of lunar or space settlements. Recent proposals to utilize the helium-3 isotope (He-3) derived from the lunar regolith as a fuel for fusion reactors would result in the availability of large quantities of other lunar volatile compounds. The quantities obtained would provide the annual life support replacement requirements of 1150 to 23,000 inhabitants per ton of He-3 recovered, depending on the volatile compound. Utilization of the lunar volatile compounds for life support depends on the costs, in terms of materials and energy, associated with their extraction from the lunar regolith as compared to the delivery costs of these compounds from Earth resources. Considering today's conservative estimated transportation costs ($10,000 dollars per kilogram) and regolith mining costs ($5 dollars per ton), the life support replacement requirements could be more economically supplied by recovering the lunar volatile compounds than transporting these materials from Earth resources, even before He-3 will be utilized as a fusion fuel. In addition, availability of lunar volatile compounds could have a significant cost impact on maintaining the life support systems of the space station and a Mars base

Supraclavicular decompression for neurogenic thoracic outlet syndrome in adolescent and adult populations

ObjectiveThis study was conducted to better define clinical results and understand factors determining responsiveness to surgical treatment for neurogenic thoracic outlet syndrome (NTOS) in adolescent and adult populations.MethodsA retrospective review was conducted for 189 patients with disabling NTOS who underwent primary supraclavicular decompression (scalenectomy, brachial plexus neurolysis and first rib resection, with or without pectoralis minor tenotomy) from April 2008 to December 2010. Clinical characteristics were compared between 35 adolescent patients (aged <21 years) and 154 adults (aged >21 years). Functional outcome measures were assessed before surgery and at 3- and 6-month follow-up using a composite NTOS Index combining the Disabilities of the Arm, Shoulder and Hand (DASH) survey, the Cervical-Brachial Symptom Questionnaire (CBSQ), and a 10-point visual analog scale (VAS) for pain.ResultsAdolescent and adult patients were not significantly different with respect to sex (overall 72.5% female), side affected (58.7% right, 60.3% dominant limb), bony anomalies (23.3%), previous injury (55.6%), coexisting pain disorders (11.1%), and positive responses to scalene muscle anesthetic blocks (95.6%). Compared with adults, adolescent patients had a significantly (P < .05) lower incidence of depression (11.4% vs 41.6%), motor vehicle injury (5.7% vs 20.1%), previous operations (11.4% vs 29.9%), preoperative use of opiate medications (17.1% vs 44.8%), and symptom duration >2 years (24.2% vs 50.0%). Mean preoperative NTOS Index (scale 0-100) was significantly lower in adolescent vs adult patients (46.5 ± 3.6 vs 58.5 ± 1.7; P = .009), and hospital length of stay was 4.4 ± 0.2 vs 4.9 ± 0.1 days (P = .03), but the rate of postoperative complications was no different (overall, 4.2%). Although both groups exhibited significant improvement in functional outcome measures at 3 and 6 months, adolescent patients had significantly lower NTOS Index (10.4 ± 3.1 vs 39.3 ± 3.3; P < .001) and use of opiate medications (11.4% vs 47.4%; P < .001) compared with adults.ConclusionsAdolescents undergoing supraclavicular decompression for NTOS had more favorable preoperative characteristics and enhanced 3-month and 6-month functional outcomes than adults. Further study is needed to delineate the age-dependent and independent factors that promote optimal surgical outcomes for NTOS

Protocol on a multicentre statistical and economic modelling study of risk-based stratified and personalised screening for diabetes and its complications in India (SMART India)

INTRODUCTION: The aim of this study is to develop practical and affordable models to (a) diagnose people with diabetes and prediabetes and (b) identify those at risk of diabetes complications so that these models can be applied to the population in low-income and middle-income countries (LMIC) where laboratory tests are unaffordable. METHODS AND ANALYSIS: This statistical and economic modelling study will be done on at least 48 000 prospectively recruited participants aged 40 years or above through community screening across 20 predefined regions in India. Each participant will be tested for capillary random blood glucose (RBG) and complete a detailed health-related questionnaire. People with known diabetes and all participants with predefined levels of RBG will undergo further tests, including point-of-care (POC) glycated haemoglobin (HbA1c), POC lipid profile and POC urine test for microalbuminuria, retinal photography using non-mydriatic hand-held retinal camera, visual acuity assessment in both eyes and complete quality of life questionnaires. The primary aim of the study is to develop a model and assess its diagnostic performance to predict HbA1c diagnosed diabetes from simple tests that can be applied in resource-limited settings; secondary outcomes include RBG cut-off for definition of prediabetes, diagnostic accuracy of cost-effective risk stratification models for diabetic retinopathy and models for identifying those at risk of complications of diabetes. Diagnostic accuracy inter-tests agreement, statistical and economic modelling will be performed, accounting for clustering effects. ETHICS AND DISSEMINATION: The Indian Council of Medical Research/Health Ministry Screening Committee (HMSC/2018–0494 dated 17 December 2018 and institutional ethics committees of all the participating institutions approved the study. Results will be published in peer-reviewed journals and will be presented at national and international conferences. TRIAL REGISTRATION: ISRCTN57962668 V1.0 24/09/2018

Frailty among older adults and its distribution in England

Background: Information on the spatial distribution of the frail population is crucial to inform service planning in health and social care. Objectives: To estimate small-area frailty prevalence among older adults using survey data. To assess whether prevalence differs between urban, rural, coastal and inland areas of England. Design: Using data from the English Longitudinal Study of Ageing (ELSA), ordinal logistic regression was used to predict the probability of frailty, according to age, sex and area deprivation. Probabilities were applied to demographic and economic information in 2020 population projections to estimate the district-level prevalence of frailty. Results: The prevalence of frailty in adults aged 50+ (2020) in England was estimated to be 8.1 [95% CI 7.3–8.8]%. We found substantial geographic variation, with the prevalence of frailty varying by a factor of 4.0 [3.5–4.4] between the most and least frail areas. A higher prevalence of frailty was found for urban than rural areas, and coastal than inland areas. There are widespread geographic inequalities in healthy ageing in England, with older people in urban and coastal areas disproportionately frail relative to those in rural and inland areas. Conclusions: Interventions aimed at reducing inequalities in healthy ageing should be targeted at urban and coastal areas, where the greatest benefit may be achieved

Extensive Chaos in the Nikolaevskii Model

We carry out a systematic study of a novel type of chaos at onset ("soft-mode turbulence") based on numerical integration of the simplest one dimensional model. The chaos is characterized by a smooth interplay of different spatial scales, with defect generation being unimportant. The Lyapunov exponents are calculated for several system sizes for fixed values of the control parameter $\epsilon$. The Lyapunov dimension and the Kolmogorov-Sinai entropy are calculated and both shown to exhibit extensive and microextensive scaling. The distribution functional is shown to satisfy Gaussian statistics at small wavenumbers and small frequency.Comment: 4 pages (including 5 figures) LaTeX file. Submitted to Phys. Rev. Let

Protocol on a multicentre statistical and economic modelling study of risk-based stratified and personalised screening for diabetes and its complications in India (SMART India)

Introduction The aim of this study is to develop practical and affordable models to (a) diagnose people with diabetes and prediabetes and (b) identify those at risk of diabetes complications so that these models can be applied to the population in low-income and middle-income countries (LMIC) where laboratory tests are unaffordable. Methods and analysis This statistical and economic modelling study will be done on at least 48 000 prospectively recruited participants aged 40 years or above through community screening across 20 predefined regions in India. Each participant will be tested for capillary random blood glucose (RBG) and complete a detailed health-related questionnaire. People with known diabetes and all participants with predefined levels of RBG will undergo further tests, including point-of-care (POC) glycated haemoglobin (HbA1c), POC lipid profile and POC urine test for microalbuminuria, retinal photography using non-mydriatic hand-held retinal camera, visual acuity assessment in both eyes and complete quality of life questionnaires. The primary aim of the study is to develop a model and assess its diagnostic performance to predict HbA1c diagnosed diabetes from simple tests that can be applied in resource-limited settings; secondary outcomes include RBG cut-off for definition of prediabetes, diagnostic accuracy of cost-effective risk stratification models for diabetic retinopathy and models for identifying those at risk of complications of diabetes. Diagnostic accuracy inter-tests agreement, statistical and economic modelling will be performed, accounting for clustering effects. Ethics and dissemination The Indian Council of Medical Research/Health Ministry Screening Committee (HMSC/2018–0494 dated 17 December 2018 and institutional ethics committees of all the participating institutions approved the study. Results will be published in peer-reviewed journals and will be presented at national and international conferences. Trial registration number ISRCTN57962668 V1.0 24/09/2018

Household wealth, neighbourhood deprivation and frailty amongst middle-aged and older adults in England: a longitudinal analysis over 15 years (2002-2017)

Background: frailty is a condition of reduced function and health due to ageing processes and is associated with a higher risk of falls, hospitalisation, disability and mortality. Objective: to determine the relationship between household wealth and neighbourhood deprivation with frailty status, independently of demographic factors, educational attainment and health behaviours. Design: population-based cohort study. Setting: communities in England. Subjects: in total 17,438 adults aged 50+ from the English Longitudinal Study of Ageing. Methods: multilevel mixed-effects ordered logistic regression was used in this study. Frailty was measured using a frailty index. We defined small geographic areas (neighbourhoods) using English Lower layer Super Output Areas. Neighbourhood deprivation was measured by the English Index of Multiple Deprivation, grouped into quintiles. Health behaviours included in this study are smoking and frequency of alcohol consumption. Results: the proportion of respondents who were prefrail and frail were 33.8% [95% confidence interval (CI) 33.0-34.6%] and 11.7 (11.1-12.2)%, respectively. Participants in the lowest wealth quintile and living in the most deprived neighbourhood quintile had 1.3 (95% CI = 1.2-1.3) and 2.2 (95% CI = 2.1-2.4) times higher odds of being prefrail and frail, respectively, than the wealthiest participants living in the least deprived neighbourhoods Living in more deprived neighbourhood and poorer wealth was associated with an increased risk of becoming frail. Those inequalities did not change over time. Conclusions: in this population-based sample, living in a deprived area or having low wealth was associated with frailty in middle-aged and older adults. This relationship was independent of the effects of individual demographic characteristics and health behaviours

Household wealth, neighbourhood deprivation and frailty amongst middle-aged and older adults in England: a longitudinal analysis over 15 years (2002-2017)

BACKGROUND: frailty is a condition of reduced function and health due to ageing processes and is associated with a higher risk of falls, hospitalisation, disability and mortality. OBJECTIVE: to determine the relationship between household wealth and neighbourhood deprivation with frailty status, independently of demographic factors, educational attainment and health behaviours. DESIGN: population-based cohort study. SETTING: communities in England. SUBJECTS: in total 17,438 adults aged 50+ from the English Longitudinal Study of Ageing. METHODS: multilevel mixed-effects ordered logistic regression was used in this study. Frailty was measured using a frailty index. We defined small geographic areas (neighbourhoods) using English Lower layer Super Output Areas. Neighbourhood deprivation was measured by the English Index of Multiple Deprivation, grouped into quintiles. Health behaviours included in this study are smoking and frequency of alcohol consumption. RESULTS: the proportion of respondents who were prefrail and frail were 33.8% [95% confidence interval (CI) 33.0-34.6%] and 11.7 (11.1-12.2)%, respectively. Participants in the lowest wealth quintile and living in the most deprived neighbourhood quintile had 1.3 (95% CI = 1.2-1.3) and 2.2 (95% CI = 2.1-2.4) times higher odds of being prefrail and frail, respectively, than the wealthiest participants living in the least deprived neighbourhoods Living in more deprived neighbourhood and poorer wealth was associated with an increased risk of becoming frail. Those inequalities did not change over time. CONCLUSIONS: in this population-based sample, living in a deprived area or having low wealth was associated with frailty in middle-aged and older adults. This relationship was independent of the effects of individual demographic characteristics and health behaviours

Characterizing unforced multi-decadal variability of ENSO:a case study with the GFDL CM2.1 coupled GCM

Large multi-decadal fluctuations of El Niño-Southern Oscillation (ENSO) variability simulated in a 4000-year pre-industrial control run of GFDL CM2.1 have received considerable attention due to implications for constraining the causes of past and future changes in ENSO. We evaluated the mechanisms of this low-frequency ENSO modulation through analysis of the extreme epochs of CM2.1 as well as through the use of a linearized intermediate-complexity model of the tropical Pacific, which produces reasonable emulations of observed ENSO variability. We demonstrate that the low-frequency ENSO modulation can be represented by the simplest model of a linear, stationary process, even in the highly nonlinear CM2.1. These results indicate that CM2.1’s ENSO modulation is driven by transient processes that operate at interannual or shorter time scales. Nonlinearities and/or multiplicative noise in CM2.1 likely exaggerate the ENSO modulation by contributing to the overly active ENSO variability. In contrast, simulations with the linear model suggest that intrinsically-generated tropical Pacific decadal mean state changes do not contribute to the extreme-ENSO epochs in CM2.1. Rather, these decadal mean state changes actually serve to damp the intrinsically-generated ENSO modulation, primarily by stabilizing the ENSO mode during strong-ENSO epochs. Like most coupled General Circulation Models, CM2.1 suffers from large biases in its ENSO simulation, including ENSO variance that is nearly twice that seen in the last 50 years of observations. We find that CM2.1’s overly strong ENSO variance directly contributes to its strong multi-decadal modulation through broadening the distribution of epochal variance, which increases like the square of the long-term variance. These results suggest that the true spectrum of unforced ENSO modulation is likely substantially narrower than that in CM2.1. However, relative changes in ENSO modulation are similar between CM2.1, the linear model tuned to CM2.1, and the linear model tuned to observations, underscoring previous findings that relative changes in ENSO variance can robustly be compared across models and observations

The effect of videokeratoscope faceplate design on radius of curvature maps

A computer model using finite ray tracing methods was developed to simulate a videokeratoscope analysing an average cornea. Different faceplate designs were tested using five points in the faceplate subtending angles between 15 and 75 in 15 intervals at the corneal vertex. Image quality was assessed by adding the geometrical blurs of the 5 image points. Differences (error) between accurate sagittal radius of curvature and sagittal radius of curvature calculated by the van Saarloos algorithm were calculated for selected surfaces at the same corneal points. The calculations were repeated for the tangential radius of curvature. Differences equal or bigger than 0.02 mm were regarded as clinically significant. The surface that provided the sharpest image for an average cornea was a cylinder with the base 120 mm away from the corneal vertex and a diameter of 26 mm. Changing the faceplate design results in clinically significant differences for an average cornea