The global, regional, and national burden of oesophageal cancer and its attributable risk factors in 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

Background Oesophageal cancer is a common and often fatal cancer that has two main histological subtypes: oesophageal squamous cell carcinoma and oesophageal adenocarcinoma. Updated statistics on the incidence and mortality of oesophageal cancer, and on the disability-adjusted life-years (DALYs) caused by the disease, can assist policy makers in allocating resources for prevention, treatment, and care of oesophageal cancer. We report the latest estimates of these statistics for 195 countries and territories between 1990 and 2017, by age, sex, and Socio-demographic Index (SDI), using data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD). Methods We used data from vital registration systems, vital registration-samples, verbal autopsy records, and cancer registries, combined with relevant modelling, to estimate the mortality, incidence, and burden of oesophageal cancer from 1990 to 2017. Mortality-to-incidence ratios (MIRs) were estimated and fed into a Cause of Death Ensemble model (CODEm) including risk factors. MIRs were used for mortality and non-fatal modelling. Estimates of DALYs attributable to the main risk factors of oesophageal cancer available in GBD were also calculated. The proportion of oesophageal squamous cell carcinoma to all oesophageal cancers was extracted by use of publicly available data, and its variation was examined against SDI, the Healthcare Access and Quality (HAQ) Index, and available risk factors in GBD that are specific for oesophageal squamous cell carcinoma (eg, unimproved water source and indoor air pollution) and for oesophageal adenocarcinoma (gastro-oesophageal reflux disease). Findings There were 473 000 (95% uncertainty interval [95% UI] 459 000–485 000) new cases of oesophageal cancer and 436 000 (425 000–448 000) deaths due to oesophageal cancer in 2017. Age-standardised incidence was 5·9 (5·7–6·1) per 100 000 population and age-standardised mortality was 5·5 (5·3–5·6) per 100 000. Oesophageal cancer caused 9·78 million (9·53–10·03) DALYs, with an age-standardised rate of 120 (117–123) per 100 000 population. Between 1990 and 2017, age-standardised incidence decreased by 22·0% (18·6–25·2), mortality decreased by 29·0% (25·8–32·0), and DALYs decreased by 33·4% (30·4–36·1) globally. However, as a result of population growth and ageing, the total number of new cases increased by 52·3% (45·9–58·9), from 310 000 (300 000–322 000) to 473 000 (459 000–485 000); the number of deaths increased by 40·0% (34·1–46·3), from 311 000 (301 000–323 000) to 436 000 (425 000–448 000); and total DALYs increased by 27·4% (22·1–33·1), from 7·68 million (7·42–7·97) to 9·78 million (9·53–10·03). At the national level, China had the highest number of incident cases (235 000 [223 000–246 000]), deaths (213 000 [203 000–223 000]), and DALYs (4·46 million [4·25–4·69]) in 2017. The highest national-level age-standardised incidence rates in 2017 were observed in Malawi (23·0 [19·4–26·5] per 100 000 population) and Mongolia (18·5 [16·4–20·8] per 100 000). In 2017, age-standardised incidence was 2·7 times higher, mortality 2·9 times higher, and DALYs 3·0 times higher in males than in females. In 2017, a substantial proportion of oesophageal cancer DALYs were attributable to known risk factors: tobacco smoking (39·0% [35·5–42·2]), alcohol consumption (33·8% [27·3–39·9]), high BMI (19·5% [6·3–36·0]), a diet low in fruits (19·1% [4·2–34·6]), and use of chewing tobacco (7·5% [5·2–9·6]). Countries with a low SDI and HAQ Index and high levels of indoor air pollution had a higher proportion of oesophageal squamous cell carcinoma to all oesophageal cancer cases than did countries with a high SDI and HAQ Index and with low levels of indoor air pollution. Interpretation Despite reductions in age-standardised incidence and mortality rates, oesophageal cancer remains a major cause of cancer mortality and burden across the world. Oesophageal cancer is a highly fatal disease, requiring increased primary prevention efforts and, possibly, screening in some high-risk areas. Substantial variation exists in age-standardised incidence rates across regions and countries, for reasons that are unclear. Funding Bill & Melinda Gates Foundation

Impact de renforts FRP précontraints sur la valeur des contraintes interfaciales des structures renforcées par composites collés

Cet article présente une nouvelle approche théorique d’analyse des contraintes interfaciales sur les structures renforcées par composites FRP précontraints, en tenant compte du modèle de chargement mécanique, de l’effet shear lag et de l’impact des précontraintes. Ces renforts FRP précontraints sont, en particulier, utilisés pour réhabiliter les structures par composites collés, en arrêtant la propagation des fissures, en donnant plus de rigidité et de résistance à la structure permettant ainsi de prolonger leur durée de vie. Dans ce travail, un aspect original est présenté, il permet de prévoir et déterminer la concentration des contraintes aux bords des renforts FRP par une approche analytique et de donner plus de précision par rapport aux méthodes précédentes qui ont négligé l’effet des renforts FRP précontraints couplés avec les différentes charges appliquées. La résolution numérique a été finalisée en tenant compte des paramètres physiques et géométriques des éléments de la structure qui peuvent jouer un rôle important dans la diminution de la valeur des contraintes

Contraintes interfaciales des structures renforcées par composites : effets thermiques et shear lag

Les matériaux composites en fibres de polymères (FRP) ont des propriétés physiques qui sont exploitées récemment pour le renfoncement des structures soumises à des risques de défaillances ou de dégradation, dus à un environnement sollicité en permanence. Ces composites sont, en particulier, utilisés pour prolonger la durée de vie de ces structures et de les protéger contre l'agressivité de leur environnement. Le renforcement donne naissance à des concentrations des contraintes dans l'interface structure adhésive. Dans ce travail de recherche, l'originalité est de prédire et de déterminer cette concentration de contraintes, par l'analyse des effets thermiques couplés avec un modèle de déformation de la structure sous l'effet de cisaillement. Nous avons développé une nouvelle approche théorique qui est une suite de celle faite par R. Denton (2001), dont il a traité le cas thermique seulement. La résolution a été validée en tenant compte aussi bien des paramètres physiques des matériaux composites, que des propriétés géométriques des éléments renforcés

Solution théorique améliorée pour étudier les interfaces des structures hybrides déformables, renforcées par composites FRP

Ce travail présente une solution améliorée pour l'étude des contraintes interfaciales des structures renforcées par composites FRP, en intégrant le couplage entre les charges appliquées et, le modèle tenant en compte la charge thermique et l'effet de déformation de cisaillement, de la structure et de la plaque composite, appelé effet "shear lag". Ces composites FRP sont, en particulier, utilisés pour prolonger la durée de vie de ces structures et protéger leur environnement. Le renforcement par composites permet d'augmenter la rigidité et la résistance de la structure, mais donne des concentrations de contraintes dans le joint adhésif à l'interface de la zone de renforcement. Dans ce travail de recherche, une originalité est présentée pour prédire et déterminer cette concentration des contraintes dues à des effets de couplage, en développant, ainsi, une nouvelle approche théorique. Ces deux types de sollicitations couplées permettent de donner des valeurs de contraintes qui diffèrent, notamment, par rapport aux méthodes précédentes qui, ont négligé l'effet de déformation, particulièrement, aux bords de la zone renforcée. La résolution numérique a été finalisée, en tenant compte des paramètres physiques et géométriques des matériaux. La tendance a été en conformité avec les travaux de la littérature

Magnetic control of WEST plasmas through deep reinforcement learning

Submitted for publication in Transaction on Plasma Science, special issue for SOFETokamaks require magnetic control across a wide range of plasma scenarios. The coupled behavior of plasma dynamics makes deep learning a suitable candidate for efficient control in order to fulfil these high-dimensional and non-linear situations. For example, on TCV, deep reinforcement learning has already been used for tracking of the plasma's magnetic equilibrium [1]. In this work, we apply such methods to the WEST tokamak, to address control of the plasma's shape, position, and current, in several relevant configurations. To this end, we developed a distributed framework to train an actorcritic agent on a C++ free boundary equilibrium code called NICE, in which resistive diffusion allows a more representative evolution of current profile throughout the simulation. The interface between components was done through UDS protocols for fast, asynchronous and reliable communication. The implemented tool handles feedback control of quantities of interest, with results showing flexibility of the method regarding the use of different training environments

Free vibrations of moderately thick truncated conical shells filled with quiescent fluid

A novel reduced order formulation is proposed for the vibration analysis of conical shells containing stationary fluid. Hamiltonian approach is followed to obtain the governing equations of motion for the structure. Utilizing the Navier-Stokes equations and simplifying for irrotational, compressible and inviscid assumptions, the final fluid equation is obtained. A general solution based on the Galerkin method is proposed for the conical shell in vacuum. Several boundary conditions are investigated to show the capability of the proposed solution. A novel reduced order formulation based on the finite element method is developed for solution of the fluid equation. Static condensation technique is also utilized to minimize the required number of degrees of freedom and speed up the solution. The main advantage of the current solution method is the use of minimal number of degrees of freedom yet giving highly accurate results. Effects of added mass, semi-vertex angle, boundary conditions and different fluid containments on the natural frequencies of the coupled-field problem are studied and some useful conclusions are drawn