Modeling, characterization, and processing of advanced composites

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The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Filament wound pipes optimization platform development: a methodological approach

A multi-objective and multi-level optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes in oil and gas industries. At the first stage, regulated design constraints are identified. Required computational tools for predicting structural properties of the composite pipes are developed and validated through experimental study. Then, the pipe design procedure is formulated as an engineering optimization problem where a hybrid design-optimization platform is developed to deal with that. The platform integrates multi-objective genetic algorithm on level 1 with a premutation-based direct search approach on level 2. It is aimed to minimize the cost of the pipe while maximum values for other structural properties are expected. Manufacturing limitations are also taken into account as the constraints in addition to design requirements

A study on fracture behavior of semi-elliptical 3D crack in claypolymer nanocomposites considering interfacial debonding

In the current research, the influence of clay platelet on crack characteristics of fully exfoliated clay/polymer matrix is scrutinized. A multi-scale 3-D finite element model comprising of four phases as clay platelet, non-perfect bond interactions, interphase region and surrounding matrix is constructed to investigate semi-elliptical matrix crack properties, as a nano-notch, subjected to fracture mode I. Subsequently, the strain energy release rate is acquired in terms of J-integral parameter considering the location and dimension, geometrical variables and modeling strategy. The results imply on the pronounced effect of clay debonding on crack behavior which leads to local stiffness reduction. Furthermore, interphase characteristics such as thickness and elastic modulus, have significant influences on the critical energy release rate. The results are consistent with published literatures and the model can be invoked as a viable tool to investigate the fracture behaviors of clay/polymer nanocomposites

A Study on Equivalent Spherical Structure of Buckyball-C 60 Based on Continuum Shell Model

Abstract The main goal of this research is to extract a suitable continuum modeling of buckyball-C60. For this purpose, firstly the lattice structure of buckyball-C60 is modelled and subsequently a spherical structure equivalent to fullerene structure is considered. The fullerene structure modeled with shell elements is under internal pressure and in the continuum shell modeling process. The results of simulation demonstrate that the fullerene structure can be modelled using spherical structure. The comparison between strain energies of the equivalent fullerene spherical model and molecular mechanics model under radial displacement, shows that C60-fullerene spherical structures can be modeled using a shell with 0.665 Å thickness, 5.07 TPa elastic modulus and 0.165 Poisson's ratio or a shell with 0.75 Å thickness, 4.84 TPa elastic modulus and 0.19 Poisson's ratio. Moreover, the applied elliptical strain is used to demonstrate that the performance of the continuum spherical shell model of C60 is faultless

Challenges of the Modeling Methods for Investigating the Interaction between the CNT and the Surrounding Polymer

The interaction between the carbon nanotubes (CNT) and the polymer is a key factor for determining the mechanical, thermal, and electrical properties of the CNT/polymer nanocomposite. However, it is difficult to measure experimentally the interfacial bonding properties between the CNT and the surrounding polymer. Therefore, computational modeling is used to predict the interaction properties. Different scale models, from atomistic to continuum, are critically reviewed addressing the advantages, the disadvantages, and the future challenges. Various methods of improvement for measuring the interaction properties are described. Finally, it is concluded that the semicontinuum modeling may be the best candidate for modeling the interaction between the CNT and the polymer