Carbon Dioxide Decomposition by a Parallel-Plate Plasma Reactor: Experiments and 2-D Modelling

The applicability of high voltage electrical discharges for the decomposition of CO2 has been extensively demonstrated. In this study, a new AC parallel-plate plasma reactor is presented which was designed for this purpose. Detailed experimental characterization and simulation of this reactor were performed. Gas chromatography of the exhaust gases enabled calculation of the CO2 conversion and energy efficiency. A conversion factor approximating 25% was obtained which is higher in comparison to existing plasma sources. Optical emission spectroscopy enabled the determination of the emission intensities of atoms and molecules inside the plasma and characterization of the discharge. The Stark broadening of the Balmer hydrogen line Hβ was used for the estimation of the electron density. The obtained densities were of the order of 5 × 1014 cm−3 which indicates that the electron kinetic energy dominated the discharge. The rotational, vibrational, and excitation temperatures were determined from the vibro-rotational band of the OH radical. A 2-temperature plasma was found where the estimated electron temperatures (~18,000 K) were higher than the gas temperatures (~2000 K). Finally, a 2-D model using the fluid equations was developed for determining the main processes in the CO2 splitting. The solution to this model, using the finite element method, gave the temporal and spatial behaviors of the formed species densities, the electric potential, and the temperatures of electrons

Numerical study of the effect of adding corona discharge based on plasma actuator on flow control performance in a horizontal axis wind turbine with rough surfaces

The use of renewable energy has recently become very common in most countries of today's society. Among these renewable energies, wind energy is one of the most attractive methods of mechanical energy production, and different methods of flow control, including active, semi-active and passive, have been investigated by various researchers. To control the fluid flow in an active way on the wind turbine blade, the corona discharge actuator based on plasma is considered the most appropriate method to reduce the fluid flow separation on the wind turbine blade. In this paper, we present a numerical simulation to integrate active load control using a corona discharge based on plasma actuators over the roughness blade. Effects of roughness, actuators voltage and frequency on aerodynamics parameters such as separation point, lift and drag coefficients have been showed. Present results showed that, the lift coefficient increase with increase in the voltage and frequency of plasma actuators. Overall, using the roughness for outer surface of blade would decrease the critical pressure coefficient by approximately 50% compared to that for the smooth surface

継承語年少学習者と第二言語学習者 : ロシア語教育の方法

<p>(G1) (Normal control group); (G2) (Ulcer control group); (G3) (Omeprazole); (G4) (62.5 mg/kg), (G5) (125 mg/kg), (G6) (250 mg/kg) and (G7) (500 mg/kg) of <i>V</i>. <i>pubescens</i> extract. HSP70 protein was over-expressed in rats pre-treated with omeprazole or <i>V</i>. <i>pubescens</i> extract (brown color shows over-expression of HSP70 protein) (magnification 20×). There were 6 rats in each group of experiment. The Image J program was used to evaluate protein expression. All values are expressed as the means ± the standard error of mean. The mean difference was significant at the <i>p < 0</i>.<i>05</i> level compared to the cancer control group.</p

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家族看護学が看護の専門領域として確立され発展していくため,今後の研究の方向性を明らかにしたいと,国内外の家族および家族看護学に関する文献の数量的動向と研究領域別文献概観を行った結果,国内外ともに家族,家族の健康,家族援助に関する研究報告は増加傾向にあり,家族への関心の高まりと実践上の必要性が反映されていた。また,わが国では高齢化社会における家族援助の要求が家族看護学の確立を促していること,今後は家族を対象とした評価方法の開発や援助に関する予防的・実践的研究が求められていることが示唆された。The review of the literature on family nursing through numerical trend and research fields was done to know how to establish and develop nursing specialty in this area. The followings were suggested. 1) The researches concerning family, family health, and family practice were increasing in both inside and outside of Japan. 2) ln U. S. A., family nursing was developed in the field of maternal-child and psychiatric nursing, introducing family system theory. In Japan family nursing is rather essential in the field of home care for the aeed, due to aging population. 3) Further researches on development of assessment tool, intervention and social support are necessary, especially by preventive and practical points of view

Air quality and urban sustainable development: the application of machine learning tools

[EN] Air quality has an efect on a population¿s quality of life. As a dimension of sustainable urban development, governments have been concerned about this indicator. This is refected in the references consulted that have demonstrated progress in forecasting pollution events to issue early warnings using conventional tools which, as a result of the new era of big data, are becoming obsolete. There are a limited number of studies with applications of machine learning tools to characterize and forecast behavior of the environmental, social and economic dimensions of sustainable development as they pertain to air quality. This article presents an analysis of studies that developed machine learning models to forecast sustainable development and air quality. Additionally, this paper sets out to present research that studied the relationship between air quality and urban sustainable development to identify the reliability and possible applications in diferent urban contexts of these machine learning tools. To that end, a systematic review was carried out, revealing that machine learning tools have been primarily used for clustering and classifying variables and indicators according to the problem analyzed, while tools such as artifcial neural networks and support vector machines are the most widely used to predict diferent types of events. The nonlinear nature and synergy of the dimensions of sustainable development are of great interest for the application of machine learning tools.Molina-Gómez, NI.; Díaz-Arévalo, JL.; López Jiménez, PA. (2021). Air quality and urban sustainable development: the application of machine learning tools. 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Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-Adjusted life-years for 29 cancer groups, 1990 to 2017 : A systematic analysis for the global burden of disease study

Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data. Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning. Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-Adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence. Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572000 deaths and 15.2 million DALYs), and stomach cancer (542000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601000 deaths and 17.4 million DALYs), TBL cancer (596000 deaths and 12.6 million DALYs), and colorectal cancer (414000 deaths and 8.3 million DALYs). Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care. © 2019 American Medical Association. All rights reserved.Peer reviewe

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Improving productivity in road pavement maintenance and rehabilitation in New Zealand : a thesis presented in fulfillment of the requirements for the degree of Master of Construction Management, School of Engineering and Advanced Technology, College of Sciences, Massey University, Albany, New Zealand

Improving the productivity of the multi-billion dollar annual investment in the maintenance and rehabilitation of the roading infrastructure could bring about huge cost savings and ensure optimal use of resources and tax payers’ money. There is currently little or no research on productivity improvement of the New Zealand roading sector. This study aimed to identify productivity constraints and improvement measures in the road maintenance and rehabilitation (RMR) sector in New Zealand. The study also aimed to provide insights into the RMR process and the criteria that inform strategic decisions for action. Based on a descriptive survey method, qualitative and quantitative data were gathered through pilot interviews and on-line surveys. The investigations were limited to the views of consultants and contractors involved in the New Zealand road pavement maintenance and rehabilitation sector. Content analysis and multi-attribute methods were used in the analysis of the primary data for this research. Results from the pilot interviews revealed 61 productivity constraint factors. These were aggregated into two main categories: internal and external factors, with an additional eight sub-categories. The five internal factor sub-groups were project finance, workforce, technology/process, project characteristics, and project management/project team characteristics. The three external factor sub-groups were statutory compliance, unforeseen circumstances, and “other” external forces. Results of the multi-attribute analysis showed that inaccurate estimates, lack of good leadership management capacity, resistance to accept new technologies in road maintenance projects, site location and environmental constraints, and frequency of design changes/change orders/late changes were the most influential internal constraint factors on the level of productivity in the road maintenance and rehabilitation sector in New Zealand. Additionally, the Health and Safety in Employment Act, Resource Management Act, inclement weather, market conditions and the level of competition in the industry for jobs were the most significant factors under the broad category of external constraints. Recommendations for improving productivity in the New Zealand RMR sector include providing more training courses for the workforce to participate in, in order to improve the level of skills and experience in the work force; having sufficient budget for using new technologies, such as road failure detection systems; using new cost-effective materials with a longer life cycle; providing accurate estimations; applying up-to-date leadership management skills; and improving the quality and accuracy of designs to minimise design errors and late change orders; as well as having adequate planning and regular monitoring of the entire process. It is expected that the application of these recommendations by designers, project managers and contractors could lift efficiency and productivity in the RMR sector and ensure optimal use of resources in the sector, as well as boost the New Zealand economy