Computing with and without arbitrary large numbers

In the study of random access machines (RAMs) it has been shown that the availability of an extra input integer, having no special properties other than being sufficiently large, is enough to reduce the computational complexity of some problems. However, this has only been shown so far for specific problems. We provide a characterization of the power of such extra inputs for general problems. To do so, we first correct a classical result by Simon and Szegedy (1992) as well as one by Simon (1981). In the former we show mistakes in the proof and correct these by an entirely new construction, with no great change to the results. In the latter, the original proof direction stands with only minor modifications, but the new results are far stronger than those of Simon (1981). In both cases, the new constructions provide the theoretical tools required to characterize the power of arbitrary large numbers.Comment: 12 pages (main text) + 30 pages (appendices), 1 figure. Extended abstract. The full paper was presented at TAMC 2013. (Reference given is for the paper version, as it appears in the proceedings.

Effect of comprehensive smoke-free legislation on neonatal mortality and infant mortality across 106 middle-income countries:a synthetic control study

Background There are few quantitative studies into the effect of comprehensive smoke-free legislation on neonatal and infant mortality in middle-income countries. We aimed to estimate the effects of implementing comprehensive smoke-free legislation on neonatal mortality and infant mortality across all middle-income countries. Methods We applied the synthetic control method using 1990-2018 country-level panel data for 106 middle-income countries from the WHO, World Bank, and Penn World datasets. Outcome variables were neonatal (age 0-28 days) mortality and infant (age 0-12 months) mortality rates per 1000 livebirths per year. For each middle-income country with comprehensive smoke-free legislation, a synthetic control country was constructed from middle-income countries without comprehensive smoke-free legislation, but with similar prelegislation trends in the outcome and predictor variables. Overall legislation effect was the mean average of country-specific effects weighted by the number of livebirths. We compared the distribution of the legislation effects with that of the placebo effects to assess the likelihood that the observed effect was related to the implementation of smoke-free legislation and not merely influenced by other processes. Findings 31 (29%) of 106 middle-income countries introduced comprehensive smoke-free legislation and had outcome data for at least 3 years after the intervention. We were able to construct a synthetic control country for 18 countries for neonatal mortality and for 15 countries for infant mortality. Comprehensive smoke-free legislation was followed by a mean yearly decrease of 1.63% in neonatal mortality and a mean yearly decrease of 1.33% in infant mortality. An estimated 12 392 neonatal deaths in 18 countries and 8932 infant deaths in 15 countries were avoided over 3 years following the implementation of comprehensive smoke-free legislation. We estimated that an additional 104 063 infant deaths (including 95 850 neonatal deaths) could have been avoided over 3 years if the 72 control middle-income countries had introduced this legislation in 2015. 220 (43%) of 514 placebo effects for neonatal mortality and 112 (39%) of 289 for infant mortality were larger than the estimated aggregated legislation effect, indicating a degree of uncertainty around our estimates. Sensitivity analyses showed results that were consistent with the main analysis and suggested a dose-response association related to comprehensiveness of the legislation. Interpretation Implementing comprehensive smoke-free legislation in middle-income countries could substantially reduce preventable deaths in neonates and infants. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd.Funding Agencies|Dutch Heart Foundation; Lung Foundation Netherlands; Dutch Cancer Society; Dutch Diabetes Research Foundation; Netherlands Thrombosis Foundation; Health Data Research UK</p

Two-Dimensional Critical Percolation: The Full Scaling Limit

We use SLE(6) paths to construct a process of continuum nonsimple loops in the plane and prove that this process coincides with the full continuum scaling limit of 2D critical site percolation on the triangular lattice -- that is, the scaling limit of the set of all interfaces between different clusters. Some properties of the loop process, including conformal invariance, are also proved.Comment: 45 pages, 12 figures. This is a revised version of math.PR/0504036 without the appendice

PERSonalised Incentives for Supporting Tobacco cessation (PERSIST) among healthcare employees: a randomised controlled trial protocol

BACKGROUND: Smoking is the primary preventable risk factor for disease and premature mortality. It is highly addictive and cessation attempts are often unsuccessful. Incentive-based programmes may be an effective method to reach sustained abstinence. Individualisation of incentives based on personal characteristics yields potential to further increase the effectiveness of incentive-based programmes. METHOD: A randomised controlled trial among healthcare workers recruited through their employer and signed up for a group-based smoking cessation programme. The intervention under study is the provision of personalised incentives on validated smoking cessation at several time points after the smoking cessation programme. A total of 220 participants are required. Participants are randomised 1:1 into intervention (personalised incentives) or control (no incentives). All participants join the group-based programme. Incentives are provided on validated abstinence directly after the smoking cessation programme and after 3, 6 and 12 months.Incentives are provided according to four schemes:(1) Standard: total reward size €350, pay-out scheme: €50 (t=0), €50 (t=3 months), €50 (t=6 months) and €200 (t=12 months), (2) descending: total reward size €300, pay-out scheme: €150, €100, €50 and €0, (3) ascending: total reward size: €400, pay-out scheme: €0, €0, €50 and €350 and (4) deposit: total reward size €450, pay-out scheme: €50, €50, €150, €200; participants pay a €100 deposit, returned conditional on abstinence after 6 months.Advice on which incentive scheme suits participants best is based on willingness to provid

On Quantum Effects in a Theory of Biological Evolution

We construct a descriptive toy model that considers quantum effects on biological evolution starting from Chaitin's classical framework. There are smart evolution scenarios in which a quantum world is as favorable as classical worlds for evolution to take place. However, in more natural scenarios, the rate of evolution depends on the degree of entanglement present in quantum organisms with respect to classical organisms. If the entanglement is maximal, classical evolution turns out to be more favorable

Cigarette taxation and neonatal and infant mortality: a longitudinal analysis of 159 countries

Previous studies on the associations between cigarette taxes and infant survival have all been in high-income countries and did not examine the relative benefits of different taxation levels and structures. We evaluated longitudinal associations of cigarette taxes with neonatal and infant mortality globally. We applied country-level panel regressions using 2008–2018 annual mortality and biennial WHO tobacco taxation data. Complete data was available for 159 countries. Outcomes were neonatal and infant mortality. We conducted analyses by type of taxes (i.e. specific cigarette taxes, ad valorem taxes, and other taxes, import duties and VAT) and the income group classification of countries. Covariates included scores for other WHO recommended tobacco control policies, socioeconomic, health-care, and air quality measures. Secondary analyses investigated the associations between cigarette tax and cigarette consumption. We found that a 10 percentage-point increase in total cigarette tax as a percentage of the retail price was associated with a 2.6% (95% Confidence Interval [CI]: 1.9% to 3.2%) decrease in neonatal mortality and a 1.9% (95% CI: 1.3% to 2.6%) decrease in infant mortality globally. Estimates were similar for both excise and ad valorem taxes. We estimated that 231,220 (95% CI: 152,658 to 307,655) infant deaths could have been averted in 2018 if all countries had total cigarette tax at least 75%. 99.2% of these averted deaths would have been in low- and middle-income countries (LMICs). The secondary analysis supported causal interpretation of results by finding that a 10 percentage-point increase in taxes was associated with a reduction of 94.6 (95% CI: 32.7 to 156.5) in annual cigarette consumption per capita. Although causal inference is precarious due to the quasi-experimental design, we used a robust analytical approach and focused on within-country changes. Limitations include an inability to include data on roll-your-own tobacco, other forms of tobacco use, and reliance on taxation data only for the cigarette brands most sold in each country. In line with limited existing evidence conducted in HICs, we found that raising taxes on tobacco was associated with a reduction in neonatal and infant mortality globally. Implementing recommended levels of taxation in LMICs should be a priority since this is where the lowest levels of taxation and the largest potential infant mortality benefits exis

Area minimizing discs in metric spaces

We solve the classical problem of Plateau in the setting of proper metric spaces. Precisely, we prove that among all disc-type surfaces with prescribed Jordan boundary in a proper metric space there exists an area minimizing disc which moreover has a quasi-conformal parametrization. If the space supports a local quadratic isoperimetric inequality for curves we prove that such a solution is locally Hölder continuous in the interior and continuous up to the boundary. Our results generalize corresponding results of Douglas Radò and Morrey from the setting of Euclidean space and Riemannian manifolds to that of proper metric spaces

Feel4Diabetes healthy diet score: Development and evaluation of clinical validity

Background: The aim of this paper is to present the development of the Feel4Diabetes Healthy Diet Score and to evaluate its clinical validity. Methods: Study population consisted of 3268 adults (63% women) from high diabetes risk families living in 6 European countries. Participants filled in questionnaires at baseline and after 1 year, reflecting the dietary goals of the Feel4Diabetes intervention. Based on these questions the Healthy Diet Score was constructed, consisting of the following components: breakfast, vegetables, fruit and berries, sugary drinks, whole-grain cereals, nuts and seeds, low-fat dairy products, oils and fats, red meat, sweet snacks, salty snacks, and family meals. Maximum score for each component was set based on its estimated relative importance regarding T2DM risk, higher score indicating better quality of diet. Clinical measurements included height, weight, waist circumference, heart rate, blood pressure, and fasting blood sampling, with analyses of glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides. Analysis of (co) variance was used to compare the Healthy Diet Score and its components between countries and sexes using baseline data, and to test differences in clinical characteristics between score categories, adjusted for age, sex and country. Pearson''s correlations were used to study the association between changes from baseline to year 1 in the Healthy Diet Score and clinical markers. To estimate reproducibility, Pearson''s correlations were studied between baseline and 1 year score, within the control group only. Results: The mean total score was 52.8 ± 12.8 among women and 46.6 ± 12.8 among men (p < 0.001). The total score and its components differed between countries. The change in the Healthy Diet Score was significantly correlated with changes in BMI, waist circumference, and total and LDL cholesterol. The Healthy Diet Score as well as its components at baseline were significantly correlated with the values at year 1, in the control group participants. Conclusion: The Feel4Diabetes Healthy Diet Score is a reproducible method to capture the dietary information collected with the Feel4Diabetes questionnaire and measure the level of and changes in the adherence to the dietary goals of the intervention. It gives a simple parameter that associates with clinical risk factors in a meaningful manner