Corrosion of Carbon Steel in Artificial Geothermal Brine: Influence of Carbon Dioxide at 70 °C and 150 °C

This study focuses on the corrosion mechanism of carbon steel exposed to an artificial geothermal brine influenced by carbon dioxide (CO2) gas. The tested brine simulates a geothermal source in Sibayak, Indonesia, containing 1500 mg/L of Cl−, 20 mg/L of SO42−, and 15 mg/L of HCO3− with pH 4. To reveal the temperature effect on the corrosion behavior of carbon steel, exposure and electrochemical tests were carried out at 70 °C and 150 °C. Surface analysis of corroded specimens showed localized corrosion at both temperatures, despite the formation of corrosion products on the surface. After 7 days at 150 °C, SEM images showed the formation of an adherent, dense, and crystalline FeCO3 layer. Whereas at 70 °C, the corrosion products consisted of chukanovite (Fe2(OH)2CO3) and siderite (FeCO3), which are less dense and less protective than that at 150 °C. Control experiments under Ar-environment were used to investigate the corrosive effect of CO2. Free corrosion potential (Ecorr) and electrochemical impedance spectroscopy (EIS) confirm that at both temperatures, the corrosive effect of CO2 was more significant compared to that measured in the Ar-containing solution. In terms of temperature effect, carbon steel remained active at 70 °C, while at 150 °C, it became passive due to the FeCO3 formation. These results suggest that carbon steel is more susceptible to corrosion at the near ground surface of a geothermal well, whereas at a deeper well with a higher temperature, there is a possible risk of scaling (FeCO3 layer). A longer exposure test at 150 °C with a stagnant solution for 28 days, however, showed the unstable FeCO3 layer and therefore a deeper localized corrosion compared to that of seven-day exposed specimens

Factores que afectan el ciclo de vida del producto en las empresas electrónicas: evidencia de un país emergente

Introduction:This paper is the product of the study “Factors affecting product life cycle in electronic enterprises – Evidence from an emerging country” developed at the Electric Power University and National Economics University between 2020 and 2022. Problem:The electronic manufacturing industry is increasingly developing in emerging markets and integrating into the global economy. The life cycle of electronic products is shorter and requires management.Objective:The paper aims to study factors that affect the product life cycle in Vietnamese electronic enterprises. The study helps managers in cost management. Methodology:The paper used a survey of non-probability sampling, and applied regression analysis to examine Vietnamese electronic enterprises. The analysis is done by SPSS and Smart PLS software. Results:The research results indicate that technology, consumer trends, and R&D are factors affecting product life cycle and post-sale service, and disposal has no impact on electronic products’ life cycle. This could be explained by the fact that electronic products are constantly updating and their life cycle is short, that post-sales service does not play a key role, and that waste treatment after sales is not taken seriously by manufacturers, customers, or other related parties. Conclusion:The results give some meaningful insights for electronics or other enterprises in Vietnam to use effective management of product life cycle. Originality:The results of this paper provide practical insights into the management of product life cycle and cost management of product life cycle for researchers and managers.Limitations:The research model should be expanded and the sample size increased to get an overview and greater insight.Introducción: Este artículo es producto del estudio “Factores que afectan el ciclo de vida del producto en empresas electrónicas – Evidencia de un país emergente” desarrollado en la Electric Power University y la National Economics University entre 2020 y 2022.Problema: La industria de fabricación electrónica se está desarrollando cada vez más en los mercados emer-gentes y se está integrando a la economía global. El ciclo de vida de los productos electrónicos es más corto y requiere gestión. Objetivo: El documento tiene como objetivo estudiar los factores que afectan el ciclo de vida del producto en las empresas electrónicas vietnamitas. El estudio ayuda a los gerentes en la gestión de costos. Metodología: El documento utilizó una encuesta de muestreo no probabilístico y aplicó un análisis de regresión para examinar las empresas electrónicas vietnamitas. El análisis se realiza mediante el software SPSS y Smart PLS. Resultados: Los resultados de la investigación indican que la tecnología, las tendencias de consumo y la I+D son factores que afectan el ciclo de vida del producto y el servicio postventa, y que el desecho no tiene impacto en el ciclo de vida de los productos electrónicos. Esto podría explicarse por el hecho de que los productos electrónicos se actualizan constantemente y su ciclo de vida es corto, que el servicio posventa no juega un papel clave y que el tratamiento de residuos posventa no es tomado en serio por los fabricantes, clientes u otras partes relacionadas. Conclusión: Los resultados brindan algunas ideas significativas para la electrónica u otras empresas en Vietnam para utilizar una gestión eficaz del ciclo de vida del producto. Originalidad: los resultados de este documento brindan información práctica sobre la gestión del ciclo de vida del producto y la gestión de costos del ciclo de vida del producto para investigadores y gerentes.Limitaciones: el modelo de investigación debe ampliarse y aumentar el tamaño de la muestra para obtener una visión general y una mayor comprensión

Enhanced electrochemiluminescence of N-(aminobutyl)-N-(ethylisoluminol) functionalized gold nanoparticles by Graphene Oxide Nanoribbons

The mechanism of electrochemiluminescence (ECL) of an N-(aminobutyl)-N-(ethylisoluminol) -functionalized gold nanoparticle (ABEI-AuNP) hybrid with graphene oxide nanoribbons (GONRs) as a functional supporting matrix on a modified screen-printed electrode (SPE) was studied under alkaline conditions.In our catalytic system, ABEI-AuNPs supported by GONRs were profoundly superior to the unsupported ABEI-AuNP/SPE, and exhibited greatly enhanced ECL intensity (≈30.0%).This difference is attributed not only to an 80.2% increase in the total surface area of the ABEI-AuNP-GONR/SPE, but also to enhancements of the ABEI-AuNP catalytic activity resulting from metal-oxygen bonding between the functional groups on the GONRs and the Au active sites.This improved catalytic activity of ABEI-AuNP facilitates both oxidative radical generation and fast reaction kinetics of the ABEI oxidation process. To further elucidate the mechanism of the counter-peak phenomenon in the ABEI ECL under cyclic voltammetry (CV) conditions, the effects of various factors, including pH of buffer solution, existence of dissolved oxygen, and concentration of hydrogen peroxide, on the ECL of ABEI were investigated.The mechanisms of liquid-phase ABEI on bare SPE and GONR/SPE were also compared to that of solid-phase ABEI-AuNP to validate the proposed mechanism for ABEI-AuNP-GONR/SPE

Trends in, projections of, and inequalities in reproductive, maternal, newborn and child health service coverage in Vietnam 2000-2030: A Bayesian analysis at national and sub-national levels

Background: To assess the reproductive, maternal, newborn and child health (RMNCH) service coverage in Vietnam with trends in 2000-2014, projections and probability of achieving targets in 2030 at national and sub-national levels; and to analyze the socioeconomic, regional and urban-rural inequalities in RMNCH service indicators. Methods: We used national population-based datasets of 44,624 households in Vietnam from 2000 to 2014. We applied Bayesian regression models to estimate the trends in and projections of RMNCH indicators and the probabilities of achieving the 2030 targets. Using the relative index, slope index, and concentration index of inequality, we examined the patterns and trends in RMNCH coverage inequality. Findings: We projected that 9 out of 17 health service indicators (53%) would likely achieve the 2030 targets at the national level, including at least one and four ANC visits, BCG immunization, access to improved water and adequate sanitation, institutional delivery, skilled birth attendance, care-seeking for pneumonia, and ARI treatment. We observed very low coverages and zero chance of achieving the 2030 targets at national and sub-national levels in early initiation and exclusive breastfeeding, family planning needs satisfied, and oral rehydration therapy. The most deprived households living in rural areas and the Northwest, Northeast, North Central, Central Highlands, and Mekong River Delta regions would not reach the 80% immunization coverage of DPT3, Polio3, Measles and full immunization. We found socioeconomic, regional, and urban-rural inequalities in all RMNCH indicators in 2014 and no change in inequalities over 15 years in the lowest-coverage indicators. Interpretation: Vietnam has made substantial progress toward UHC. By improving the government\u27s health system reform efforts, re-allocating resources focusing on people in the most impoverished rural regions, and restructuring and enhancing current health programs, Vietnam can achieve the UHC targets and other health-related SDGs

Improvement in neoantigen prediction via integration of RNA sequencing data for variant calling

IntroductionNeoantigen-based immunotherapy has emerged as a promising strategy for improving the life expectancy of cancer patients. This therapeutic approach heavily relies on accurate identification of cancer mutations using DNA sequencing (DNAseq) data. However, current workflows tend to provide a large number of neoantigen candidates, of which only a limited number elicit efficient and immunogenic T-cell responses suitable for downstream clinical evaluation. To overcome this limitation and increase the number of high-quality immunogenic neoantigens, we propose integrating RNA sequencing (RNAseq) data into the mutation identification step in the neoantigen prediction workflow.MethodsIn this study, we characterize the mutation profiles identified from DNAseq and/or RNAseq data in tumor tissues of 25 patients with colorectal cancer (CRC). Immunogenicity was then validated by ELISpot assay using long synthesis peptides (sLP).ResultsWe detected only 22.4% of variants shared between the two methods. In contrast, RNAseq-derived variants displayed unique features of affinity and immunogenicity. We further established that neoantigen candidates identified by RNAseq data significantly increased the number of highly immunogenic neoantigens (confirmed by ELISpot) that would otherwise be overlooked if relying solely on DNAseq data.DiscussionThis integrative approach holds great potential for improving the selection of neoantigens for personalized cancer immunotherapy, ultimately leading to enhanced treatment outcomes and improved survival rates for cancer patients

Quantifying antimicrobial access and usage for paediatric diarrhoeal disease in an urban community setting in Asia.

OBJECTIVES: Antimicrobial-resistant infections are a major global health issue. Ease of antimicrobial access in developing countries is proposed to be a key driver of the antimicrobial resistance (AMR) epidemic despite a lack of community antimicrobial usage data. METHODS: Using a mixed-methods approach (geospatial mapping, simulated clients, healthcare utilization, longitudinal cohort) we assessed antimicrobial access in the community and quantified antimicrobial usage for childhood diarrhoea in an urban Vietnamese setting. RESULTS: The study area had a pharmacy density of 15.7 pharmacies/km2 (a pharmacy for every 1316 people). Using a simulated client method at pharmacies within the area, we found that 8% (3/37) and 22% (8/37) of outlets sold antimicrobials for paediatric watery and mucoid diarrhoea, respectively. However, despite ease of pharmacy access, the majority of caregivers would choose to take their child to a healthcare facility, with 81% (319/396) and 88% (347/396) of responders selecting a specialized hospital as one of their top three preferences when seeking treatment for watery and mucoid diarrhoea, respectively. We calculated that at least 19% (2688/14427) of diarrhoea episodes in those aged 1 to <5 years would receive an antimicrobial annually; however, antimicrobial usage was almost 10 times greater in hospitals than in the community. CONCLUSIONS: Our data question the impact of community antimicrobial usage on AMR and highlight the need for better education and guidelines for all professionals with the authority to prescribe antimicrobials

Effects of water scarcity awareness and climate change belief on recycled water usage willingness: Evidence from New Mexico, United States

The global water crisis is being exacerbated by climate change, even in the United States. Recycled water is a feasible alternative to alleviate the water shortage, but it is constrained by humans’ perceptions. The current study examines how residents’ water scarcity awareness and climate change belief influence their willingness to use recycled water directly and indirectly. Bayesian Mindsponge Framework (BMF) analytics was employed on a dataset of 1831 residents in Albuquerque, New Mexico, an arid inland region in the US. We discovered that residents’ willingness to use direct recycled potable water is positively affected by their awareness of water scarcity, but the effect is conditional on their belief in the impacts of climate change on the water cycle. Meanwhile, the willingness to use indirect recycled potable water is influenced by water scarcity awareness, and the belief in climate change further enhances this effect. These findings implicate that fighting climate change denialism and informing the public of the water scarcity situation in the region can contribute to the effectiveness and sustainability of long-term water conservation and climate change alleviation efforts