Juan Pablo Orjuela

Juan Pablo Orjuela
Imperial College London | Imperial · Centre for Environmental Policy

M.Eng, MSc

About

48
Publications
10,408
Reads
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850
Citations
Citations since 2017
38 Research Items
846 Citations
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2017201820192020202120222023050100150200

Publications

Publications (48)
Article
Full-text available
Previous research has shown that walking and cycling could help alleviate stress in cities, however there is poor knowledge on how specific microenvironmental conditions encountered during daily journeys may lead to varying degrees of stress experienced at that moment. We use objectively measured data and a robust causal inference framework to addr...
Article
Full-text available
Background Stress is one of many ailments associated with urban living, with daily travel a potential major source. Active travel, nevertheless, has been associated with lower levels of stress compared to other modes. Earlier work has relied on self-reported measures of stress, and on study designs that limit our ability to establish causation. Ob...
Article
Full-text available
Active travel (walking or cycling for transport) is considered the most sustainable form of personal transport. Yet its net effects on mobility-related CO2 emissions are complex and under-researched. Here we collected travel activity data in seven European cities and derived life cycle CO2 emissions across modes and purposes. Daily mobility-related...
Poster
Full-text available
Background/Aim: Not much is known about the role of repeated peak exposures in longer term exposure and health. In fact, no clear definition of peak exposure to air pollution exists. We aimed to develop an algorithm to automatically signal peaks in black carbon (BC) timeseries; we studied the role of personal characteristics, including time-activit...
Article
Background Ubiquitous sensing technology provides novel opportunities for integrating activity patterns in exposure assessment. Theoretically promising to generate population-wide activity-based exposures, in reality strong limitations to widespread and large-scale use exist. Methods and results from three contrasting studies are presented. Methods...
Article
Background: Air quality standards are typically based on long term averages - whereas a person may encounter exposure peaks throughout the day. Exposure peaks may contribute meaningfully to health impacts beyond their contribution to long term averages, and therefore should be considered alongside longer-term exposures. We aim to define and explain...
Article
Aim: To assess the main and interaction effects of black carbon and physical activity on arterial blood pressure in a healthy adult population from three European cities using objective personal measurements over short-term (hours and days) and long-term exposure. Methods: A panel study of 122 healthy adults was performed in three European citie...
Article
Background: Transport mode choice has been associated with different health risks and benefits depending on which transport mode is used. We aimed to evaluate the association between different transport modes use and several health and social contact measures. Methods: We based our analyses on the Physical Activity through Sustainable Transport...
Article
Background: In the fight against rising overweight and obesity levels, and unhealthy urban environments, the renaissance of active mobility (cycling and walking as a transport mode) is encouraging. Transport mode has been shown to be associated to body mass index (BMI), yet there is limited longitudinal evidence demonstrating causality. We aimed to...
Article
Full-text available
Subjective perception of air pollution is important and can have impacts on health in its own rights, can lead to protective behaviour, or it can be leveraged to engage citizens and stakeholders in support of cleaner air policies. The aim of the current analysis was to examine associations between level of concern over health effects of air polluti...
Article
Full-text available
Introduction: When physical activity is promoted in urban outdoor settings (e.g. walking and cycling), individuals are also exposed to air pollution. It has been reported that short-term lung function increases as a response to physical activity, but this beneficial effect is hampered when elevated air pollution concentrations are observed. Our st...
Conference Paper
See full paper at: https://www.researchgate.net/publication/317871361_NO2_but_Not_PM_25_at_the_Home_Address_is_Associated_with_Concern_over_Health_Effects_of_Air_Pollution Background/aim People living in urban areas in Europe are exposed to elevated concentrations of air pollution. The lower the air pollution levels, the better for your health; s...
Conference Paper
Background/aim Transport behaviours have been associated with several positive and negative health effects. The current study evaluates the association between different modes of transport and subjective general health in an adult population in seven European cities, and explores whether mental health, vitality, perceived stress, social contacts, a...
Article
Abstract While the annual number of trips of the average urban inhabitant has grown steadily in recent years, people are becoming less active while doing so. This lack of physical activity causes major health problems for individuals and great economic costs for society as a whole. Replacing short motorized trips by walking and cycling has been sho...
Article
Background There is increasing evidence that active mobility contributes to overall physical activity, and is negatively associated with obesity. However, the associations between active mobility, physical activity and body weight are complex. In the current analysis, a number of research gaps are tackled (e.g. including leisure-time physical activ...
Article
Background Active mobility (ie walking and cycling) has been associated with health benefits like increasing levels of physical activity and reduction of cardiovascular risk in the general population. However, increased inhalation rate during physical activity may result in increased inhaled dose of traffic-related air pollutants. short-term exposu...
Article
Background People living in urban areas in Europe are exposed to elevated concentrations of traffic-related air pollution. The lower the air pollution levels, the better for your health; so people exposed to higher concentrations should be worried more about air pollution. But are they? The aim of this analysis was to examine associations between c...
Article
Reduction of sedentary time and an increase in physical activity offer potential to improve public health. However, quantifying physical activity behaviour under real world conditions is a major challenge and no standard of good practice is available. Our aim was to compare the results of physical activity and sedentary behaviour obtained with a se...
Article
Full-text available
Background Physical inactivity is the fourth leading cause of global mortality. Hence, the Physical Activity through Sustainable Transport Approaches (PASTA) study aims to promote active mobility (i.e. walking and cycling) as an innovative measure to increase physical activity levels. Studying the health benefits of an increase in active mobility i...
Article
Full-text available
Reduction of sedentary time and an increase in physical activity offer potential to improve public health. However, quantifying physical activity behaviour under real world conditions is a major challenge and no standard of good practice is available. Our aim was to compare the results of physical activity and sedentary behaviour obtained with a se...
Data
Dataset including the relevant data without demographic information. –Demographic information was not added due to privacy concerns. (XLSX)
Data
Characteristics of volunteers enrolled in 1) the PASTA online survey in all cities 2) the PASTA online survey in Antwerp (ANT), Barcelona (BCN) and London (LDN) only 3) the study using wearables (all participants and each city separately). Physical activity variables of the online survey sample are derived from the GPAQ asking about general behavio...
Data
The Global Physical Activity Questionnaire (GPAQ). The GPAQ was adjusted to capture information on walking, cycling and e-biking trips separately. (PDF)
Data
Boxplots of MVPA time, moderate time and vigorous time per measurement method and session. Δ = the mean difference between both methods per session (tested for significance using the Wilcoxon signed rank sum test); r = the Spearman correlation coefficient per session; rrm = the overall Spearman correlation adjusted for repeated measures (rm); pΔ(t)...
Data
Sedentary minutes measured by the GPAQ in function of SB measured by the SenseWear. The Spearman correlation coefficients for session 1, session 2 and session 3 are respectively 0.09, 0.25 and 0.24 (overall rrm = 0.12). SW = SenseWear. (PDF)
Data
Bland-Altman plots comparing MVPA, moderate and vigorous time (minutes/week) measured by the SenseWear armband (SW) and the GPAQ. All percentage differences on the Y-axis are calculated by subtracting GPAQ from SenseWear results divided by their average. Moderate and vigorous intensity activities included influential observation. The red, dashed li...
Article
Considering the key role of the transport sector in the economy and its contribution to greenhouse gas (GHG) and local air pollutant emissions, the development of integrated techniques to evaluate long-term urban trends should be a top priority for creating a more sustainable society. This paper presents an integrated model for reliable estimation...
Article
Physical activity and ventilation rates have an effect on an individual's dose and may be important to consider in exposure-response relationships; however, these factors are often ignored in environmental epidemiology studies. The aim of this study was to evaluate methods to estimate the inhaled dose of air pollution and understand variability, in...
Article
Background: Transport microenvironments tend to have higher air pollutant concentrations than other settings most people encounter in their daily lives. The choice of travel modes may affect significantly individuals' exposures; however such considerations are typically not accounted for in exposure assessment used in environmental health studies....
Article
Abstract Intro Personal exposure to air pollution in cities varies in great deal due to position in space and time and the microenvironments visited. Transport also plays an important role in daily exposures and the choices of route and mode are believed to have a significant impact in daily inhaled doses of city dwellers. Although there is a grow...
Article
Full-text available
Introduction Only one-third of the European population meets the minimum recommended levels of physical activity (PA). Physical inactivity is a major risk factor for non-communicable diseases. Walking and cycling for transport (active mobility, AM) are well suited to provide regular PA. The European research project Physical Activity through Sustai...
Article
Full-text available
Background: Physical inactivity is one of the leading risk factors for non-communicable diseases, yet many are not sufficiently active. The Physical Activity through Sustainable Transport Approaches (PASTA) study aims to better understand active mobility (walking and cycling for transport solely or in combination with public transport) as an innov...
Article
Background Many studies indicate that air pollution can lead to both acute and chronic health effects. From a husband/wife study (Dons et al., Atmos Environ, 2011), we know that the time-activity pattern is important in determining exposure to air pollution with a difference of up to 30% in exposure between partners. Exposure in the transport micro...
Poster
Background Lack of physical activity is the fourth leading risk factor for mortality. Many people do not reach the 150 min weekly target defined by the WHO. Walking and cycling for travel is therefore suggested as an innovative measure to increase the activity level of the population. Unfortunately, being active in traffic implies exposure to eleva...
Conference Paper
Background Estimating exposure levels and inhaled doses while traveling is an important part in the assessment of the health impacts of air pollution but it is also a challenging task. There is usually a trade-off between accurate concentrations estimates and sample size. Current research focuses mainly in air quality models for large population se...
Article
Background Health impact assessment (HIA) is a combination of methods by which a policy or intervention may be assessed and judged for its potential effects on the health of the population. The HIA is classified in four levels of depth: desk-based, rapid, intermediate and comprehensive. These different levels vary in resources, capacity, duration a...
Article
Full-text available
A bidimensional and pseudo homogenous model is proposed for the study of mass transfer in the bioadsorption process of chromium VI in the S-layer of immobilized Bacillus sphaericus. The process takes place in a packed column. The implementation of such model in COMSOL Multiphysics is explained in detail and the final results are presented. These in...

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Cited By

Projects

Project (1)
Project
The EU-funded project PASTA - Physical Activity Through Sustainable Transport Approaches - aims to connect transport and health by promoting active mobility in cities (i.e. walking and cycling) including in combination with public transport use) as an innovative way of integrating physical activity into our everyday lives. More info: http://www.pastaproject.eu/home/ Follow us on Twitter @EUPASTA