Spatial, temporal, and demographic patterns in prevalence of chewing tobacco use in 204 countries and territories, 1990-2019 : a systematic analysis from the Global Burden of Disease Study 2019

Interpretation Chewing tobacco remains a substantial public health problem in several regions of the world, and predominantly in south Asia. We found little change in the prevalence of chewing tobacco use between 1990 and 2019, and that control efforts have had much larger effects on the prevalence of smoking tobacco use than on chewing tobacco use in some countries. Mitigating the health effects of chewing tobacco requires stronger regulations and policies that specifically target use of chewing tobacco, especially in countries with high prevalence. Findings In 2019, 273 center dot 9 million (95% uncertainty interval 258 center dot 5 to 290 center dot 9) people aged 15 years and older used chewing tobacco, and the global age-standardised prevalence of chewing tobacco use was 4 center dot 72% (4 center dot 46 to 5 center dot 01). 228 center dot 2 million (213 center dot 6 to 244 center dot 7; 83 center dot 29% [82 center dot 15 to 84 center dot 42]) chewing tobacco users lived in the south Asia region. Prevalence among young people aged 15-19 years was over 10% in seven locations in 2019. Although global agestandardised prevalence of smoking tobacco use decreased significantly between 1990 and 2019 (annualised rate of change: -1 center dot 21% [-1 center dot 26 to -1 center dot 16]), similar progress was not observed for chewing tobacco (0 center dot 46% [0 center dot 13 to 0 center dot 79]). Among the 12 highest prevalence countries (Bangladesh, Bhutan, Cambodia, India, Madagascar, Marshall Islands, Myanmar, Nepal, Pakistan, Palau, Sri Lanka, and Yemen), only Yemen had a significant decrease in the prevalence of chewing tobacco use, which was among males between 1990 and 2019 (-0 center dot 94% [-1 center dot 72 to -0 center dot 14]), compared with nine of 12 countries that had significant decreases in the prevalence of smoking tobacco. Among females, none of these 12 countries had significant decreases in prevalence of chewing tobacco use, whereas seven of 12 countries had a significant decrease in the prevalence of tobacco smoking use for the period. Summary Background Chewing tobacco and other types of smokeless tobacco use have had less attention from the global health community than smoked tobacco use. However, the practice is popular in many parts of the world and has been linked to several adverse health outcomes. Understanding trends in prevalence with age, over time, and by location and sex is important for policy setting and in relation to monitoring and assessing commitment to the WHO Framework Convention on Tobacco Control. Methods We estimated prevalence of chewing tobacco use as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 using a modelling strategy that used information on multiple types of smokeless tobacco products. We generated a time series of prevalence of chewing tobacco use among individuals aged 15 years and older from 1990 to 2019 in 204 countries and territories, including age-sex specific estimates. We also compared these trends to those of smoked tobacco over the same time period. Findings In 2019, 273 & middot;9 million (95% uncertainty interval 258 & middot;5 to 290 & middot;9) people aged 15 years and older used chewing tobacco, and the global age-standardised prevalence of chewing tobacco use was 4 & middot;72% (4 & middot;46 to 5 & middot;01). 228 & middot;2 million (213 & middot;6 to 244 & middot;7; 83 & middot;29% [82 & middot;15 to 84 & middot;42]) chewing tobacco users lived in the south Asia region. Prevalence among young people aged 15-19 years was over 10% in seven locations in 2019. Although global age standardised prevalence of smoking tobacco use decreased significantly between 1990 and 2019 (annualised rate of change: -1 & middot;21% [-1 & middot;26 to -1 & middot;16]), similar progress was not observed for chewing tobacco (0 & middot;46% [0 & middot;13 to 0 & middot;79]). Among the 12 highest prevalence countries (Bangladesh, Bhutan, Cambodia, India, Madagascar, Marshall Islands, Myanmar, Nepal, Pakistan, Palau, Sri Lanka, and Yemen), only Yemen had a significant decrease in the prevalence of chewing tobacco use, which was among males between 1990 and 2019 (-0 & middot;94% [-1 & middot;72 to -0 & middot;14]), compared with nine of 12 countries that had significant decreases in the prevalence of smoking tobacco. Among females, none of these 12 countries had significant decreases in prevalence of chewing tobacco use, whereas seven of 12 countries had a significant decrease in the prevalence of tobacco smoking use for the period. Interpretation Chewing tobacco remains a substantial public health problem in several regions of the world, and predominantly in south Asia. We found little change in the prevalence of chewing tobacco use between 1990 and 2019, and that control efforts have had much larger effects on the prevalence of smoking tobacco use than on chewing tobacco use in some countries. Mitigating the health effects of chewing tobacco requires stronger regulations and policies that specifically target use of chewing tobacco, especially in countries with high prevalence. Copyright (c) 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Spatial, temporal, and demographic patterns in prevalence of smoking tobacco use and attributable disease burden in 204 countries and territories, 1990-2019 : a systematic analysis from the Global Burden of Disease Study 2019

Background Ending the global tobacco epidemic is a defining challenge in global health. Timely and comprehensive estimates of the prevalence of smoking tobacco use and attributable disease burden are needed to guide tobacco control efforts nationally and globally. Methods We estimated the prevalence of smoking tobacco use and attributable disease burden for 204 countries and territories, by age and sex, from 1990 to 2019 as part of the Global Burden of Diseases, Injuries, and Risk Factors Study. We modelled multiple smoking-related indicators from 3625 nationally representative surveys. We completed systematic reviews and did Bayesian meta-regressions for 36 causally linked health outcomes to estimate non-linear dose-response risk curves for current and former smokers. We used a direct estimation approach to estimate attributable burden, providing more comprehensive estimates of the health effects of smoking than previously available. Findings Globally in 2019, 1.14 billion (95% uncertainty interval 1.13-1.16) individuals were current smokers, who consumed 7.41 trillion (7.11-7.74) cigarette-equivalents of tobacco in 2019. Although prevalence of smoking had decreased significantly since 1990 among both males (27.5% [26. 5-28.5] reduction) and females (37.7% [35.4-39.9] reduction) aged 15 years and older, population growth has led to a significant increase in the total number of smokers from 0.99 billion (0.98-1.00) in 1990. Globally in 2019, smoking tobacco use accounted for 7.69 million (7.16-8.20) deaths and 200 million (185-214) disability-adjusted life-years, and was the leading risk factor for death among males (20.2% [19.3-21.1] of male deaths). 6.68 million [86.9%] of 7.69 million deaths attributable to smoking tobacco use were among current smokers. Interpretation In the absence of intervention, the annual toll of 7.69 million deaths and 200 million disability-adjusted life-years attributable to smoking will increase over the coming decades. Substantial progress in reducing the prevalence of smoking tobacco use has been observed in countries from all regions and at all stages of development, but a large implementation gap remains for tobacco control. Countries have a dear and urgent opportunity to pass strong, evidence-based policies to accelerate reductions in the prevalence of smoking and reap massive health benefits for their citizens. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe

Finite element analysis and structure optimization of a gantry-type high-precision machine tool

Abstract The high-precision machine tool’s dynamic, static, and rigid nature directly affects the machining efficiency and surface quality. Static and dynamic analyses are essential for the design and improvement of precision machine to ensure good tool performance under difficult and demanding machining conditions. In this study, the performance of a high-precision machine tool was analyzed using its virtual model created using CAD. Static and model analysis using ANSYS Workbench software was conducted to establish the tool's static deformation and static stiffness. Furthermore, the static and dynamic characteristics of the tool were explored using a finite element modeling approach to study their performance. In particular, the structure, static force, modal, frequency spectrum, and topology optimization of machine tools were primarily analyzed. Using model analysis, we found the first four different frequencies (22.5, 28.9, 40.6, and 47.4 Hz) and vibration type, which suggested of a weak link. Further static structural analysis revealed that the deformation of the spindle was 67.26 μm. An experimental static rigidity analysis was performed, and the experimental deformation values of the tool and spindle were obtained. The static and dynamic characteristics, as well as the accuracy and efficiency of the finite element model, were verified by comparing the data with the finite element analysis (FEA) results. Subsequently, we modified the settings and analysis model to ensure that the analysis results were consistent with the experimental findings. The error between the two results was within 1.56%. For an applied load of 5000 N on the spindle nose, the tool nose transient response was 0.5 s based on transient analysis. Under the condition that the structural deformation is as constant as possible, the lightweight structure may achieve the minimum weight and enhance the natural frequency; thus, the ideal structure will be obtained, and finite element analysis will then be performed. The optimal conditions for topology optimization include a lightweight structure, reduced structural deformation, and increased natural frequency of the structure. The developed method improves structural optimization, increases the ability of the product to be manufactured, and offers designers a variety of price-effective options

Time Trend of the People lost follow up on Antiretroviral Therapy (ART) Services in Nepal: A Epidemiological Modelling

Background: The real state about the spread of the HIV epidemic in Nepal is not clear since the details available are on the basis of repeated integrated biological and behavioral surveillance. Objective To study the trends of People lost follow up on ART in future. Material and methods: A retrospective study was carried out on the data collected from the Health ministry records of Nepal, between 2006 and 2012. Descriptive statistics and statistical modelling were used for the analysis and forecasting of data. Results: Including the constant term from the equation, the quadratic model was the best fit, for the forecasting of People lost follow up on ART. Using quadratic equation, it is estimated that 4331 reported number of People lost follow up on ART will be there in Nepal by the year 2020. Conclusion: The People lost follow up on ART in Nepal are having an increasing trend. Estimates of the total number of People lost follow up on ART attributable to the major routes of infection make an important contribution to public health policy. They can be used for the planning of healthcare services and for contributing to estimates of the future numbers with People lost follow up on ART used for planning health promotion programmes

Time Trend of the People lost follow up on Antiretroviral Therapy (ART) Services in Nepal: A Epidemiological Modelling

Background: The real state about the spread of the HIV epidemic in Nepal is not clear since the details available are on the basis of repeated integrated biological and behavioral surveillance. Objective To study the trends of People lost follow up on ART in future. Material and methods: A retrospective study was carried out on the data collected from the Health ministry records of Nepal, between 2006 and 2012. Descriptive statistics and statistical modelling were used for the analysis and forecasting of data. Results: Including the constant term from the equation, the quadratic model was the best fit, for the forecasting of People lost follow up on ART. Using quadratic equation, it is estimated that 4331 reported number of People lost follow up on ART will be there in Nepal by the year 2020. Conclusion: The People lost follow up on ART in Nepal are having an increasing trend. Estimates of the total number of People lost follow up on ART attributable to the major routes of infection make an important contribution to public health policy. They can be used for the planning of healthcare services and for contributing to estimates of the future numbers with People lost follow up on ART used for planning health promotion programmes

Simultaneous observation of anti-damping and the inverse spin Hall effect in the La 0.67 Sr 0.33 MnO 3 /Pt bilayer system

Manganites have shown potential in spintronics because they exhibit high spin polarization. Here, by ferromagnetic resonance we have studied the damping properties of La0.67Sr0.33MnO3/Pt bilayers which are prepared by oxide molecular beam epitaxy. The damping coefficient (α) of a La0.67Sr0.33MnO3 (LSMO) single layer is found to be 0.0104. However the LSMO/Pt bilayers exhibit a decrease in α with an increase in Pt thickness. This decrease in the value of α is probably due to high anti-damping like torque. Furthermore, we have investigated the angle dependent inverse spin Hall effect (ISHE) to quantify the spin pumping voltage from other spin rectification effects such as the anomalous Hall effect and anisotropic magnetoresistance. We have observed a high spin pumping voltage (∼20 μV). The results indicate that both anti-damping and spin pumping phenomena occur simultaneously

Crystallization and magnetic hardening behaviour of Fe-rich FeSiBNb(Cu) melt-spun alloys

The sequential, multi-stage crystallization and magnetic hardening behaviour of Fe82B14Si2Nb2, Fe83B13Si2Nb2, Fe83B12Si2Nb2Cu1 and Fe85B13Nb2 melt-spun alloys have been investigated. The microstructure-crystallization-magnetic property relationship was established using X-ray diffractometry (XRD), differential scanning calorimetry (DSC), magnetometry, transmission electron microscopy (TEM) and magneto-optical Kerr effect microscopy (MOKE) techniques. The increase of Fe content (> 82 at%) of as-quenched ribbons imparts microstructural heterogeneity across the ribbon cross-section; i.e., textured alpha-Fe crystals at the free surface to heteroamorphous microstructure in the bulk matrix. The isochronal annealing of hetero-amorphous alloys depicts simultaneous surface and bulk crystallization process occurring before and after the crystallization onset temperature (T-x1) temperature. The annealing temperature range (T-a < T-x1) coinciding with the paramagnetic region of the thermo-magnetic plot, induces irreversible magnetic hardening due to simultaneous coarsening of pre-existing crystal nuclei and exchange de-coupling between nanocrystal and intergranular matrix. The onset of primary crystallization in the pre-crystallized ribbons results in bimodal nanocrystallite distribution having an average crystallite size exceeding the ferromagnetic exchange length of Fe-based alloys. The minor Cu addition alters the growth morphology of pre-existing nuclei from dendrite-like to equiaxed, assisting heterogeneous nucleation and improving intergranular amorphous stability by delaying boride precipitation. The soft-magnetic property deterioration of partially crystallized ribbons is discussed within the framework of Extended-Random Anisotropy models

Crystallization and magnetic hardening behaviour of Fe-rich FeSiBNb(Cu) melt-spun alloys

The sequential, multi-stage crystallization and magnetic hardening behaviour of Fe82B14Si2Nb2, Fe83B13Si2Nb2, Fe83B12Si2Nb2Cu1 and Fe85B13Nb2 melt-spun alloys have been investigated. The microstructure-crystallizationmagnetic property relationship was established using X-ray diffractometry (XRD), differential scanning calorimetry (DSC), magnetometry, transmission electron microscopy (TEM) and magneto-optical Kerr effect microscopy (MOKE) techniques. The increase of Fe content (> 82 at%) of as-quenched ribbons imparts microstructural heterogeneity across the ribbon cross–section; i.e., textured α-Fe crystals at the free surface to heteroamorphous microstructure in the bulk matrix. The isochronal annealing of hetero-amorphous alloys depicts simultaneous surface and bulk crystallization process occurring before and after the crystallization onset temperature (Tx1) temperature. The annealing temperature range (Ta < Tx1) coinciding with the paramagnetic region of the thermo-magnetic plot, induces irreversible magnetic hardening due to simultaneous coarsening of pre-existing crystal nuclei and exchange de-coupling between nanocrystal and intergranular matrix. The onset of primary crystallization in the pre-crystallized ribbons results in bimodal nanocrystallite distribution having an average crystallite size exceeding the ferromagnetic exchange length of Fe-based alloys. The minor Cu addition alters the growth morphology of pre-existing nuclei from dendrite-like to equiaxed, assisting heterogeneous nucleation and improving intergranular amorphous stability by delaying boride precipitation. The soft-magnetic property deterioration of partially crystallized ribbons is discussed within the framework of Extended-Random Anisotropy models