1,721,233 research outputs found

    Constrained Formation Control Framework for Spacecraft Proximity Formation Flight

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    This paper presents an analytical framework for designing Artificial Potential Field (APF) gains for spacecraft formation control within the Circular Relative Orbit framework. While APF methods are effective for formation shaping, they often overlook system dynamics and constraints, risking instability. The proposed method ensures Lyapunov stability through a systematic gain design and the definition of an operational bound. Stability is verified using Structured Singular Value μ-analysis. Numerical simulations confirm the robustness and scalability of the approach, supporting safe and reliable proximity operations for future multi-satellite missions inEarth orbit

    Epidemiology of cholangiocarcinoma

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    Aim: We aimed to analyze temporal trends in mortality from intrahepatic (ICC) and extrahepatic (ECC) cholangiocarcinoma in selected countries worldwide. Methods: Official death certification data for ICC and ECC and populations estimates for 29 countries worldwide (17 from Europe, 8 from the Americas, and 4 from Australasia) and for Hong Kong Special Administrative Region of the People’s Republic of China (SAR), from 1995 to 2018, were extracted from the World Health Organization and the Pan American Health Organization databases. Age-standardized mortality rates were computed. A joinpoint regression analysis was performed. Results: In both sexes, ICC mortality rates increased in most countries considered, including the USA, the UK, and Australia; in some countries, including Italy and France, the increasing trends leveled off over the most recent years. In men, around 2016, the highest rates (1.7-2.3/100,000) were observed in Hong Kong SAR, Portugal, France, Spain, Australia, Austria, the UK, and Canada; Latin American countries and some eastern European countries had the lowest rates (0.2-0.8/100,000). A similar pattern was observed in women, but with lower rates (from 1.7/100,000 in Hong Kong SAR to 0.14/100,000 in Argentina). ECC mortality declined in most European and Australasian countries, but it tended to increase in Americas. In both sexes, rates were below 1/100,000 around 2016, with the only exceptions being Japan (2.6/100,000 men and 1.2/100,000 women) and Hungary (1.5/100,000 men and 1.1/100,000 women). Conclusion: ICC mortality increased in most areas of the world, likely due to increased prevalence of risk factors and improved cancer recognition and classification. ECC mortality fell in most countries, largely due to the widespread use of cholecystectomy

    Breast cancer mortality in the Americas and Australasia over the period 1980–2017 with predictions for 2025

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    Substantial progress has been made in the diagnosis, management, and treatment of breast cancer over the last decades. This has affected mortality rates but has also led to inequality in epidemiological trends between different regions of the world. We extracted death certification data for breast cancer from the World Health Organization database. We analyzed trends in breast cancer mortality in selected countries from America, Asia, and Oceania over the 1980–2017 period and predicted numbers of deaths and rates for 2025. In North America, we observed decreased breast cancer mortality, reaching a rate of about 13/100,000 women in 2017. In Latin American countries, breast cancer mortality rates did not consistently decrease. The highest decreases in mortality were observed in Australia. Mortality trends in Asian countries remained among the lowest globally. We have predicted decreased mortality from breast cancer in 2025 for most of the analyzed countries. The epidemiological situation regarding breast cancer mortality is expected to change in the coming years. Advancements in diagnosis and treatment of breast cancer must be extended in various areas of the world to obtain global control of breast cancer mortality

    Educational inequality in the Dietary Approach to Stop Hypertension diet in the UK: Evaluating the mediating role of income

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    Apparent differences in the adoption of the Dietary Approach to Stop Hypertension (DASH) diet have been reported between less and more educated individuals. However, the mediating role of income has not been clarified. In this study, we aimed at quantifying the mediating effect of income on the relationship between education and the DASH score in the UK population. We analysed data on 4864 subjects aged 18 years and older collected in three waves of the National Diet and Nutrition Survey (2008-2016). The DASH score was calculated using sex-specific quintiles of DASH items. We carried out a counterfactual-based mediation analysis to decompose the total effect of education on DASH score into average direct effect and average causal mediation effect mediated by income. We found that the overall mediating effect of income on the relationship between education and the DASH score was only partial, with an estimated proportion mediated ranging between 6 and 9 %. The mediating effect was higher among females (11·6 %) and younger people (17·9 %). Further research is needed to investigate which other factors may explain the socio-economic inequality in the adoption of the DASH diet in the UK

    European trends in breast cancer mortality, 1980–2017 and predictions to 2025

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    Background: Breast cancer mortality in European women has been falling for three decades. We analysed trends in mortality from breast cancer in Europe over the period 1980–2017 and predicted number of deaths and rates to 2025. Methods: We extracted death certification data for breast cancer in women for 35 European countries, between 1980 and 2017, from the World Health Organisation database. We computed the age-standardised (world standard population) mortality rates per 100,000 person-years, by country and calendar year. We obtained also predictions for 2025 using a joinpoint regression model and calculated the number of avoided deaths over the period 1994–2025. Results: The mortality rate declined from 15.0 in 2012 to 14.4 in 2017 per 100,000 women (−3.9%) for the European Union (EU)-27. This fall was greater in the EU-14 (−5.2%), whereas rates rose in the transitional countries during this period by 1.9%. Mortality rate predictions across Europe are expected to reach relatively uniform levels in 2025. During the studied period, favourable trends in mortality emerged in most countries, with the greatest decrease in Denmark, whereas Poland and Romania showed an upward trend. The largest predicted decrease in breast cancer mortality was estimated for the United Kingdom (12.2/100,000 women in 2025), leading to the estimated avoidance of 150,000 breast cancer deaths over the period 1994–2025 and 470,000 in the EU-27. Conclusions: Favourable trends in breast cancer mortality were observed in most European countries, and they will continue to fall in the coming years. Less favourable patterns were still observed among the transitional countries than other European areas

    European cancer mortality predictions for the year 2012

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    Background: Estimating current cancer mortality figures is important for defining priorities for prevention and treatment. Materials and methods: Using logarithmic Poisson count data joinpoint models on mortality and population data from the World Health Organization database, we estimated numbers of deaths and age-standardized rates in 2012 from all cancers and selected cancer sites for the whole European Union (EU) and its six more populated countries. Results: Cancer deaths in the EU in 2012 are estimated to be 1 283 101 (717 398 men and 565 703 women) corresponding to standardized overall cancer death rates of 139/100 000 men and 85/100 000 women. The fall from 2007 was 10% in men and 7% in women. In men, declines are predicted for stomach (-20%), leukemias (-11%), lung and prostate (-10%) and colorectal (-7%) cancers, and for stomach (-23%), leukemias (-12%), uterus and colorectum (-11%) and breast (-9%) in women. Almost stable rates are expected for pancreatic cancer (+2-3%) and increases for female lung cancer (+ 7%). Younger women show the greatest falls in breast cancer mortality rates in the EU (-17%), and declines are expected in all individual countries, except Poland. Conclusion: Apart for lung cancer in women and pancreatic cancer, continuing falls are expected in mortality from major cancers in the EU

    Dietary fiber and stomach cancer risk: a case-control study from Italy

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    Fiber intake has been inversely related to stomach cancer risk, although this issue is still controversial. A case-control study was conducted in Italy between 1997 and 2007, including 230 cases with incident, histologically confirmed stomach cancer, and 547 controls with acute, non-neoplastic diseases. Dietary habits were investigated through a validated food frequency questionnaire. Compared with the lowest quintile of intake, the multivariate odds ratios (ORs, including terms for major recognised confounding factors and total energy intake) for the highest quintile were 0.47 (95% confidence interval (CI): 0.28-0.79) for total fiber, 0.50 (95% CI: 0.30-0.85) for soluble non-cellulose polysaccharides (NCP), 0.39 (95% CI: 0.23-0.66) for total insoluble fiber, 0.54 (95% CI: 0.32-0.91) for insoluble NCP, 0.37 (95% CI: 0.22-0.64) for cellulose, and 0.59 (95% CI: 0.36-0.98) for lignin. With reference to the sources of fiber, an inverse association was found for fiber from vegetable (OR = 0.42, 95% CI: 0.24-0.72), and to a lesser extent from fruit (OR = 0.65, 95% CI: 0.38-1.10), but not for fiber from grain (OR = 1.25, 95% CI: 0.77-2.03). This study found an inverse relationship between stomach cancer risk and various types of fiber, derived, in particular, from vegetables and fruit
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