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The increasing demand for clean energy conversion and storage has increased interest in hydrogen production via electrolytic water splitting. However, the simultaneous production of hydrogen and oxygen in this process poses a challenge in extracting pure hydrogen without using ionic conducting membranes. Researchers have developed various innovative designs to overcome this issue, but continuous water splitting in separated tanks remains a desirable approach. This study presents a novel, continuous roll-to-roll process that enables fully decoupled hydrogen evaluation reaction (HER) and oxygen evolution reaction (OER) in two separate electrolyte tanks. The system utilizes specially designed "cable-car" electrodes (CCE) that cycle between the HER and OER tanks, resulting in continuous hydrogen production with a purity of over 99.9% and Coulombic efficiency of 98% for prolonged periods. This membrane-free water splitting system offers promising prospects for scaled-up industrial-scale green hydrogen production, as it reduces the cost and complexity of the system, and allows for the use of renewable energy sources to power the electrolysis process, thus reducing the carbon footprint of hydrogen production.

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Cable cars are a viable alternative to improve citizens' accessibility in zones with limitations on urban public transport supply due to the topography. In Latin America, such systems have recently been implemented in zones with high levels of poverty and vulnerability. Although the social implications of their implementation are relevant, individual expectations of these systems and how current changes in travel conditions and quality of life are perceived have not been widely reported in the literature. This paper aims to evaluate users' expectations and perceptions of a new cable car in the southern periphery of Bogotá (Colombia). We conducted a panel survey before (n = 341) and after (n = 301) the cable car started operations to evaluate the ranking of preferences toward a set of possible benefits of the project. We estimated discrete choice models to analyze the statistical differences between the expectations and perceptions before and after changes. Results suggest that travel time reductions, comfort improvements, and in-vehicle security are the benefits most valued by the users. Even though the project meets expectations of these aspects, it seems to fall short in expectations of reductions of pollution. Individuals' experience with the cable car shapes their perceptions of the system. We found that perceptions differ between those who have used the service at least once and those who never did. Policy implications derived from this study might be of interest to decision-makers seeking to guarantee the public acceptability of urban projects.

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In-situ field observations of vertical aerosol profiles for one month in complex terrain (Lushan Mountain, China) were carried out using a cable car, which resolved detailed vertical distributions of mountain aerosols with low-cost operation. Cable-car observations were conducted during the early morning and late afternoon, when mountain and valley winds dominated, respectively. The diurnal aerosol variations at the top and foot of Lushan Mountain were analyzed based on environmental and meteorological stations. The observations indicated that the mountain-valley breezes notably impacted the mountain-area aerosol distribution under weak weather conditions. More uniform aerosol profiles for the afternoon than the morning, with their decreasing rates of PM2.5 (particles with diameters less than 2.5 µm) were 1.64 and 2.28 µg m-3/100 m, respectively. The PM2.5/PM10 ratio at the mountain top increased from 0.69 to 0.81, and that at the mountain base decreased from 0.75 to 0.70 from morning to afternoon. The PM2.5 concentration decreased in and around Lushan Mountain from daytime to nighttime, with the impacted diameter of the 300-m topography line being smaller than ~5 km, while the concentration increased in Jiujiang City. The relative decreasing rate of PM2.5 was higher at the mountain top site (~20%) than at the base site (~2%) from daytime to nighttime. Moreover, uniform aerosol profiles could have been caused by regional transport through a relatively strong low-level synoptic flow (~5 m s-1) and the mountain's dynamic lifting effect.

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Resumen Introducción: Venezuela cuenta con uno de los sistemas de teleférico más altos del mundo, sin embargo, no se han realizado investigaciones que infieran acerca de cómo la altura incide en antropometría y condiciones de salud generales de sus trabajadores. Objetivo: determinar la relación indicadores antropométricos y saturación de oxígeno en trabajadores del sistema teleférico Mukumbarí. Mérida, Venezuela. Materiales y método: investigación no experimental, transversal y descriptiva realizada en 100 empleados ubicados en alturas de 3.452-4.765 m.s.n.m. Se calculó Índice de Masa Corporal (IMC) y perímetro de cintura (PCi) para estimar riesgo cardiometabólico (RCM) con puntos de corte OMS. La saturación de oxígeno (SPO2) obtenida por Oxímetro. Se realizaron frecuencias, Chi Cuadrado y Odds Ratio (OR) con p<0,05. Resultados: 51% sexo masculino y 49% femenino. Grupo de edad más numeroso 25-34 años (88%). Al IMC: 88% normal, 7% déficit peso, 3% sobrepeso, 2% obesidad I. Sobrepeso más común en jóvenes y déficit en mayores de 35 años. RCM aumentado y muy aumentado 52%. RCM "aumentado" predominante en hombres y "muy aumentado" en mujeres; según grupo de edad de 25 a 34 años RCM aumentado (18%) y muy aumentado (26%). SPO2 baja y muy baja presente en 70% de los estudiados, predominando la baja en hombres y la muy baja en mujeres. Las frecuencias más altas se dieron entre RCM alto y muy alto con SPO2 baja y muy baja; con OR se observó que quienes presentan RCM alto tienen 2,2 veces más riesgo de presentar SPO2 baja con 95% de confianza. Conclusión: aunque la mayor parte de la población estudiada es joven y con IMC mayormente normal, se evidenció RCM aumentado y SPO2 bajas o hipoxia en casi la totalidad de los trabajadores; lo que se reflejó en la relación epidemiológica encontrada. Se recomienda disminuir la jornada laboral y realizar nuevas investigaciones en la temática.

Abstract Introduction: Venezuela has one of the highest cable car systems in the world; however, no research has been conducted to infer how height affects anthropometry and general health conditions of workers. Objective: to determine the relationship between anthropometric indicators and oxygen saturation in workers of the Mukumbarí cable car system. Merida, Venezuela. Materials and method: non-experimental, cross-sectional and descriptive research carried out on 100 employees located at heights of 3,452-4,765 m.a.s.l. Body Mass Index (BMI) and waist circumference (PCi) were calculated to estimate cardiometabolic risk (RCM) with WHO cut-off points. The oxygen saturation (SPO2) obtained by Oximeter. Frequencies, Chi Square and Odds Ratio (OR) were performed with p <0.05. Results: 51% male and 49% female. Largest age group 25-34 (88%). At BMI: 88% normal, 7% weight deficit, 3% overweight, 2% obesity I. Most common overweight in young people and deficit in people over 35 years of age. RCM increased and greatly increased 52%. RCM "increased" predominant in men and "very increased" in women; According to age group 25 to 34, RCM increased (18%) and greatly increased (26%). Low and very low SPO2 present in 70% of those studied, predominantly low in men and very low in women. The highest frequencies were between high and very high RCM with low and very low SPO2; with OR, it was observed that those with high RCM have 2.2 times the risk of presenting low SPO2 with 95% confidence. Conclusion: although most of the population studied is young and with a mostly normal BMI, increased RCM and low SPO2 or hypoxia were evidenced in almost all of the workers; which was reflected in the epidemiological relationship found. It is recommended to reduce working hours and carry out new research on the subject.

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Background: Cable cars provide urban mobility benefits for vulnerable populations. However, no evaluation has assessed cable cars' impact from a health perspective. TransMiCable in Bogotá, Colombia, provides a unique opportunity to (1) assess the effects of its implementation on the environmental and social determinants of health (microenvironment pollution, transport accessibility, physical environment, employment, social capital, and leisure time), physical activity, and health outcomes (health-related quality of life, respiratory diseases, and homicides); and (2) use citizen science methods to identify, prioritize, and communicate the most salient negative and positive features impacting health and quality of life in TransMiCable's area, as well as facilitate a consensus and advocacy-building change process among community members, policymakers, and academic researchers. Methods: TrUST (In Spanish: Transformaciones Urbanas y Salud: el caso de TransMiCable en Bogotá) is a quasi-experimental study using a mixed-methods approach. The intervention group includes adults from Ciudad Bolívar, the area of influence of TransMiCable. The control group includes adults from San Cristóbal, an area of future expansion for TransMiCable. A conceptual framework was developed through group-model building. Outcomes related to environmental and social determinants of health as well as health outcomes are assessed using questionnaires (health outcomes, physical activity, and perceptions), secondary data (crime and respiratory outcomes) use of portable devices (air pollution exposure and accelerometry), mobility tracking apps (for transport trajectories), and direct observation (parks). The Stanford Healthy Neighborhood Discovery Tool is being used to capture residents' perceptions of their physical and social environments as part of the citizen science component of the investigation. Discussion: TrUST is innovative in its use of a mixed-methods, and interdisciplinary research approach, and in its systematic engagement of citizens and policymakers throughout the design and evaluation process. This study will help to understand better how to maximize health benefits and minimize unintended negative consequences of TransMiCable.

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