Overtaking maneuvers on two-lane highways under the microscope: Exploration of a multidimensional framework for the analysis of safety, comfort and efficiency using simulator data.

An unreasonable overtaking attempt on two-lane highways could cause drivers to suffer in terms of driving safety, comfort, and efficiency. Several external factors related to the traffic environment (e.g., speed and car type of surrounding vehicles), were found to be the significant factors in drivers' overtaking performance in the previous studies. However, the microscopic decision-making (e.g., the moments of the occupation of the opposite lane) mechanisms during overtaking, by means of which drivers react to changes in the external traffic environment and adjust their overtaking trajectories, are still need to be explored. Hence, this study had three goals: (i) To explore the spatial characteristics of micro-decisions (MDs) (such as the start and end point) in overtaking trajectories; (ii) To measure three types of performance indicators (i.e., safety, comfort, and efficiency) for the execution of overtaking maneuvers; (iii) To quantitatively explain the microscopic decision-making mechanism in overtaking. Data for overtaking trajectories were collected from driving a simulation experiment where 52 Chinese student drivers completed a series of overtaking maneuvers on a typical two-lane highway under different traffic conditions. Two analyses were conducted: firstly, the distributions of the relative distance between the ego and surrounding vehicles at four key points (i.e., the start, entry, back, and end) in the overtaking trajectory were investigated and clustered to uncover the spatial characteristics of the MDs. Secondly, the safety, comfort, and efficiency of the overtaking were measured by the aggregations of multi-targets collision risks, triaxial acceleration variances, and spatial consumptions respectively based on the Data Envelopment Analysis (DEA), which were further applied in a two-stage SEM model to reveal the quantitative interrelationships among the external factors, microscope decisions and performances in overtaking. We confirmed that the MDs could be considered as the mediating variables between the external factors and overtaking performances. In the presence of the more hazardous traffic environment (e.g., faster traffic flow and impeded by a truck), the safety, comfort and efficiency of overtaking would be deteriorated inevitably. But drivers would execute the overtaking under the longer passing sight distance, migrate their trajectories forward, and shorten the spatial duration to significantly improve the overtaking performances. Based on this mechanism, a overtaking trajectory optimization strategy for the advanced or automatic driving system, was confirmed and concluded that 1) the passing gap should be firstly planned according to the sight distance acceptance of different drivers, which directly determine the upper limit of the safety performance in the overtaking; 2) the trajectory forward migration and shortening the whole duration in overtaking could be effective to enhance the overtaking performances of the overtaking on the two-lane highway; 3) the guidance of the stable control of the steering wheel and gas/brake pedals is essential in the overtaking.

Built and natural environment correlates of physical activity of adults living in rural areas: a systematic review.

BACKGROUND: According to social-ecological models, the built and natural environment has the potential to facilitate or hinder physical activity (PA). While this potential is well researched in urban areas, a current systematic review of how the built and natural environment is related to PA in rural areas is lacking. METHODS: We searched five databases and included studies for adults (18-65 years) living in rural areas. We included quantitative studies investigating the association between any self-reported or objectively measured characteristic of the built or natural environment and any type of self-reported or objectively measured PA, and qualitative studies that reported on features of the built or natural environment perceived as barriers to or facilitators of PA by the participants. Screening for eligibility and quality assessment (using the Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields) were done in duplicate. We used a narrative approach to synthesize the results. RESULTS: Of 2432 non-duplicate records, 51 quantitative and 19 qualitative studies were included. Convincing positive relationships were found between the availability and accessibility of places for exercise and recreation and leisure-time PA as well as between the overall environment and leisure-time PA. Possible positive associations were found between the overall environment and total and transport-related PA, between greenness/natural environment and total PA, between cycling infrastructure and aesthetics and MVPA, and between pedestrian infrastructure and total walking. A possible negative relationship was found between safety and security and total walking. Qualitative studies complemented several environmental facilitators (facilities for exercise and recreation, sidewalks or streets with low traffic, attractive natural environment) and barriers (lack of facilities and destinations, lack of sidewalks, speeding traffic and high traffic volumes, lack of street lighting). CONCLUSIONS: Research investigating the relationship between the built and natural environment and PA behaviors of adults living in rural areas is still limited and there is a need for more high-quality and longitudinal studies. However, our most positive findings indicate that investing in places for exercise and recreation, a safe infrastructure for active transport, and nature-based activities are possible strategies that should be considered to address low levels of PA in rural adults. TRIAL REGISTRATION: PROSPERO: CRD42021283508.

Environmental Modifications for People With Intellectual and Developmental Disabilities: A Policy Analysis of Medicaid Home- and Community-Based Services.

IMPORTANCE: Environmental modifications are targets for occupational therapy intervention because they support activities of daily living, self-efficacy, personal control, independence, and community living for people with intellectual and developmental disabilities (IDDs). OBJECTIVE: To examine how environmental modifications were provided to people with IDDs through Medicaid home- and community-based services (HCBS) waivers across the United States in fiscal year (FY) 2021. DESIGN: Using a mixed-methods policy analysis, we examined FY 2021 Medicaid HCBS 1915(c) waivers from across the United States to examine whether, and how, states provided environmental modifications to people with IDDs. RESULTS: In FY 2021, 35 states projected spending $68.8 million on environmental modifications for 12,671 people with IDDs. The purpose of environmental modifications was most often to promote the health, welfare, and safety of people with IDDs (82.68%), and to promote their independence (69.29%). The most common examples of environmental modifications included ramps and/or lifts (70.08%), widening doorways and/or hallways (61.42%), bathroom modifications (58.27%), specialized electrical and/or plumbing for medical equipment (54.33%), and grab bars and/or handrails (53.54%). CONCLUSIONS AND RELEVANCE: HCBS waiver data on environmental modifications for people with IDDs enhances an understanding of this funding source and provides a foundation of advocacy for occupational therapy practitioners to support people with IDDs with living, as well as aging, in the community rather than in institutions. An expansion of environmental modifications in HCBS for people with IDDs aligns with the aim of Medicaid HCBS waivers to promote community integration, self-determination, and independence, which are all benefits of environmental modifications. Plain-Language Summary: This study can help occupational therapy practitioners determine what funding sources are available in their state to help their clients with intellectual and developmental disabilities access environmental modifications. The findings can also help guide advocacy and lobbying efforts to expand access to environmental modifications.

Using the Theory of Affordances to Understand Environment-Play Transactions: Environmental Taxonomy of Outdoor Play Space Features-A Scoping Review.

IMPORTANCE: The transactions between the physical environment and children's play have not been well studied. The theory of affordances provides a way to better understand how environmental characteristics offer opportunities for play occupation. OBJECTIVE: To investigate the relationship between environmental characteristics of outdoor play spaces and children's outdoor play and to develop an environmental taxonomy to support the analysis of play affordances in community play spaces. DATA SOURCES: Peer-reviewed literature (1974-2023) was sourced from a previously published scoping review (Morgenthaler, Schulze, et al., 2023). The Academic Search Complete, Avery Index to Architectural Periodicals, CINAHL, MEDLINE, PsycINFO, Scopus, and Web of Science databases were searched using the keywords and synonyms of playground, environmental qualities, and children with and without disabilities. STUDY SELECTION AND DATA COLLECTION: A secondary analysis of the previously published scoping review was conducted. Included studies were those that provided descriptions of physical environment-play activity transactions. FINDINGS: A qualitative content analysis of 45 articles was conducted and used to form an environmental taxonomy. This taxonomy consisted of 14 space and object categories defined by their functional qualities and linked to play affordances. An array of 284 play occupations were identified in different forms. Play affordances of spaces and object categories and their functional environmental qualities were subsequently identified. CONCLUSIONS AND RELEVANCE: This study provides evidence to support the understanding of how the physical environment shapes children's outdoor play occupations. Plain-Language Summary: The study authors developed the Environmental Taxonomy of Outdoor Play Space Features as a tool that occupational therapists can use to better understand and describe how the physical environment shapes opportunities for play. The tool could also be useful to justify environmental intervention in schools and public playgrounds to create spaces that support more play for a diversity of children.

Impactful co-design: Adult decision-makers' perspectives on actualising children's ideas for health-promoting neighbourhoods in Aotearoa New Zealand.

Our study sought to understand adult decision-makers' views on what was important for actualising children's ideas using co-design, towards creating health-promoting local environments. Ten adult decision-makers, experienced in co-design with children aged 5-13 years in Aotearoa New Zealand, participated in individual interviews. We generated three themes (Empowering children within co-design; Being intentional about children's influence; Curating who is involved) using reflexive thematic analysis. Our themes informed a novel framework of 'impactful co-design' accompanied by a practical checklist for adult decision-makers (practitioners, policy-makers, and researchers). Study findings affirm co-designing local neighbourhoods as an inherently social and technical endeavour, advocate for greater consideration of inclusivity and cultural context, and highlight the need for co-design with children to include safety, empowerment, and evaluation. We position impactful co-design as one useful process to enact children's meaningful participation.

The moderating effects of greenspace on the association between neighbourhood disadvantage and obesity among mid-to-older aged Australian adults.

This study examined whether the association between neighbourhood disadvantage and obesity was moderated by quantity and quality of greenspace. The sample included 2848 mid-to-older aged adults residing in 200 neighbourhoods in Brisbane, Australia from the HABITAT study. Self-reported height and weight were used to calculate body mass index (BMI), neighbourhood disadvantage was measured using a census-derived composite index and greenspace was measured geospatially. We found evidence of moderation by park quality: lower average BMI at higher levels of park quality was shown in the Q3 rather than the Q1 (least disadvantaged) neighbourhood disadvantage group. The findings suggest that, for reducing socioeconomic inequalities in obesity, the quality of greenspace is imperative.

Neighborhood physical environments and change in cardiometabolic risk factors over 14 years in the study of Women's health across the nation.

BACKGROUND: Neighborhood physical environments may influence cardiometabolic health, but prior studies have been inconsistent, and few included long follow-up periods. METHODS: Changes in cardiometabolic risk factors were measured for up to 14 years in 2830 midlife women in the Study of Women's Health Across the Nation, a multi-ethnic/racial cohort of women from seven U.S. sites. Data on neighborhood food retail environments (modified Retail Food Environment Index) and walkability (National Walkability Index) were obtained for each woman's residence at each follow-up. Data on neighborhood access to green space, parks, and supermarkets were available for subsets (32-42%) of women. Models tested whether rates of change in cardiometabolic outcomes differed based on neighborhood characteristics, independent of sociodemographic and health-related covariates. RESULTS: Living in more (vs. less) walkable neighborhoods was associated with favorable changes in blood pressure outcomes (SBP: -0.27 mmHg/year, p = 0.002; DBP: -0.22 mmHg/year, p < 0.0001; hypertension status: ratio of ORs = 0.79, p < 0.0001), and small declines in waist circumference (-0.09 cm/year, p = 0.03). Small-magnitude associations were also observed between low park access and greater increases in blood pressure outcomes (SBP: 0.37 mmHg/year, p = 0.003; DBP: 0.15 mmHg/year, p = 0.04; hypertension status: ratio of ORs = 1.16, p = .04), though associations involving DBP and hypertension were only present after adjustment for sociodemographic variables. Other associations were statistically unreliable or contrary to hypotheses. CONCLUSION: Neighborhood walkability may have a meaningful influence on trajectories of blood pressure outcomes in women from midlife to early older adulthood, suggesting the need to better understand how individuals interact with their neighborhood environments in pursuit of cardiometabolic health.

The correlation between drivers' road familiarity and glance behavior using real vehicle experimental data and mathematical models.

OBJECTIVE: Road familiarity is an important factor affecting drivers' visual features. Analyzing the quantitative correlation between drivers' road familiarity and visual features in complex environment is of great help to improve driving safety. However, there are few relevant studies. This paper takes urban plane intersection as the environmental object to explore the correlation between drivers' glance behavior and road familiarity, and conducts research on the quantitative evaluation model of road familiarity based on this correlation. METHOD: First, a real vehicle experiment was carried out to record the eye movement data of 24 drivers with different road familiarity. The driver's visual field plane was divided into 10 areas of interest (AOIs) based on the driver's perspective. Three measures, including average glance duration, number of glances, and fixation transition probabilities between AOIs at urban plane intersections, were extracted. Finally, based on the experimental results, the driver road familiarity evaluation model was constructed using the factor analysis method. RESULTS: There are significant differences between unfamiliar and familiar drivers regarding the average glance duration toward the forward (FW) area, the left window (LW) area, the left rearview mirror (LVM) area and the left forward (LF) area, the number of glances toward the other (OT) area, and the fixation transition probabilities of LW→RF (right forward), LF→LF, LF→FW, FW→LW, FW→FW, FW→RVM (right rearview mirror). The comprehensive evaluation results show that the accuracy rate of the driver road familiarity evaluation model reached 83%. CONCLUSIONS: This paper revealed that there is a strong correlation between drivers' road familiarity and drivers' glance behavior. Based on this correlation, we can include road familiarity as a part of drivers' working status and establish a high accuracy evaluation model of driver road familiarity. The conclusion of this paper can provide some reference for the humanized design and improvement of advanced driving assistance system, which is of great significance for reducing the driving workload of drivers and improving the driving safety.

Evaluating the safety and efficiency impacts of forced lane change with negative gaps based on empirical vehicle trajectories.

A lane-changing (LC) maneuver may cause the follower in the target lane (new follower) to decelerate and give up space, potentially affecting crash risk and traffic flow efficiency. In congested flow, a more aggressive LC maneuver occurs where the lane changer is partially next to the new follower and creates negative gaps, namely negative gap forced LC (NGFLC). Although NGFLC forms the foundation of sideswipe crashes, little has been done to address its impacts and the contributing factors. To tackle this issue, a total of 15,810 LC trajectory samples are extracted from three drone videos at different locations. These samples are categorized into NGFLC and normal LC groups for comparative analysis. Five commonly used conflict indicators are extended into two-dimensional to evaluate the crash risk of LC maneuver. The change of time gaps during LC maneuver are examined to quantify the impact of LC on traffic flow efficiency. We find that NGFLCs significantly increase crash risk, reflected by the number of hazardous LC events and potential crash areas compared to normal LC. Additionally, results reveal that both the lane changer and the new follower tend to maintain a larger time gap after NGFLCs. Factors including time headway, relative speed, and historical gaps in the target lane significantly affect NGFLC incidence. Once the movement of the leader in the original lane is taken into account, the prediction accuracy improves from 81% to 91%. The transferability tests indicate that the findings about the negative impact of NGFLC and the accuracy of its prediction model are consistent across different locations. These findings hold implications for driving assistance systems to better predict and mitigate NGFLCs.

A game-theoretic approach for modelling pedestrian-vehicle conflict resolutions in uncontrolled traffic environments.

The interactions of motorised vehicles with pedestrians have always been a concern in traffic safety. The major threat to pedestrians comes from the high level of interactions imposed in uncontrolled traffic environments, where road users have to compete over the right of way. In the absence of traffic management and control systems in such traffic environments, road users have to negotiate the right of way while avoiding conflict. Furthermore, the high level of movement freedom and agility of pedestrians, as one of the interactive parties, can lead to exposing unpredictable behaviour on the road. Traffic interactions in uncontrolled mixed traffic environments will become more challenging by fully/partially automated driving systems' deployment, where the intentions and decisions of interacting agents must be predicted/detected to avoid conflict and improve traffic safety and efficiency. This study aims to formulate a game-theoretic approach to model pedestrian interactions with passenger cars and light vehicles (two-wheel and three-wheel vehicles) in uncontrolled traffic settings. The proposed models employ the most influencing factors in the road user's decision and choice of strategy to predict their movements and conflict resolution strategies in traffic interactions. The models are applied to two data sets of video recordings collected in a shared space in Hamburg and a mid-block crossing area in Surat, India, including the interactions of pedestrians with passenger cars and light vehicles, respectively. The models are calibrated using the identified conflicts between users and their conflict resolution strategies in the data sets. The proposed models indicate satisfactory performances considering the stochastic behaviour of road users - particularly in the mid-block crossing area in India - and have the potential to be used as a behavioural model for automated driving systems.

Safety-in-Numbers for route choice of bicycle trips: A choice experiment approach for commuters.

Safety-in-Numbers (SiN) implies that the risk of collision per road user is less when there are more road users. Although the available literature has confirmed the existence of SiN as an objective measure of safety, the effect on perceived safety, especially in the context of bicycle riders, has received much less attention. This study investigates the SiN effect on the perceived safety of bicycle riders that influences route choice behavior. A stated preference survey was performed in the South Delhi district of Delhi. The effect of attributes like posted speed limit, the volume of motorized traffic, bicycle infrastructure, and bicycle traffic/ crowding on route choice behavior was investigated. A binary logit model was developed to quantify the effect of these attributes on route choice. The results indicate that, in general, riders prefer routes with more bicycle traffic, hence validating SiN. But the effect does not always hold. For some riders, in the presence of dedicated bicycle infrastructure, when the perceived safety is higher, the presence of more bicycle traffic acts as crowding and demotivates riders to choose that route. The study also reveals that riders prefer routes with a low volume of motorized traffic and dedicated bicycle infrastructure. The outcomes suggest that a policy that encourages infrastructural development to provide lateral separation will encourage more people, hence increasing bicycle mode share as well as the perceived safety of riders.

Neighbourhood walkability and greenspace and their associations with health-related fitness in urban dwelling Canadian adults.

OBJECTIVE: Muscular strength and body composition are important components of health-related fitness (HRF). Grip strength and body fat percent, in particular, are associated with chronic disease and affected by health behaviours. Evidence suggests relationships between the neighbourhood built environment (BE) and HRF exist, however, few studies have focused on grip strength and body fat percent. Therefore, our study aimed to estimate the sex-specific associations between the neighbourhood BE, grip strength, and body fat percent among urban-dwelling Canadian adults. METHODS: We analyzed cross-sectional survey and HRF data collected in 2011-2015 from 4052 males and 7841 females (Alberta's Tomorrow Project, Canada). Grip strength and body fat percent were measured via handgrip dynamometry and bioelectrical impedance analysis, respectively. Walkability (Canadian Active Living Index) and greenness (Normalized Difference Vegetation Index) estimates were linked to participant data. Sex-stratified covariate-adjusted linear regression models estimated the associations between the BE and HRF variables. RESULTS: Walkability was negatively associated with grip strength and body fat percent in males (ß -0.21, 95%CI: -0.31 to -0.11 and ß -0.08, 95%CI: -0.15 to -0.02, respectively) and females (ß -0.06, 95%CI: -0.10 to -0.01 and ß -0.08, 95%CI: -0.14 to -0.02, respectively). Greenness was positively associated with grip strength in males (ß 6.99, 95%CI: 3.62 to 10.36) and females (ß 2.72, 95%CI: 1.22 to 4.22) but not with body fat percent. Controlling for physical activity and sitting did not attenuate these associations. CONCLUSION: Characteristics of the neighbourhood BE appear to be associated with muscular strength and body composition, independent of physical activity and sedentary behaviour.

Pedestrian crash risk analysis using extreme value models: New insights and evidence.

Facilitating proactive pedestrian safety management, the application of extreme value theory (EVT) models has gained popularity due to its extrapolation capabilities of estimating crashes from their precursors (i.e., conflicts). However, past studies either applied EVT models for crash risk analysis of autonomous vehicle-pedestrian interactions or human-driven vehicle-pedestrian interactions at signalised intersections. However, our understanding of human-driven vehicle-pedestrian interactions remains elusive because of scant evidence of (i) EVT models' application for heterogeneous traffic conditions, (ii) appropriate set of determinants, (iii) which EVT approach to be used, and (iv) which conflict measure is appropriate. Addressing these issues, the objective of this study is to investigate pedestrian crash risk analysis in heterogeneous and disordered traffic conditions, where drivers do not follow lane disciplines. Eleven-hour video recording was collected from a busy pedestrian crossing at a midblock location in India and processed using artificial intelligence techniques. Vehicle-pedestrian interactions are characterised by two conflict measures (i.e., post encroachment time and gap time) and modelled using block maxima and peak over threshold approaches. To handle the non-stationarity of pedestrian conflict extremes, several explanatory variables are included in the models, which are estimated using the maximum likelihood estimation procedure. Modelling results indicate that the EVT models provide reasonable estimates of historical crash records at the study location. From the EVT models, a few key insights related to vehicle-pedestrian interactions are as follows. Firstly, a comparison of EVT models shows that the peak over threshold model outperforms the block maxima model. Secondly, post encroachment time conflict measure is found to be appropriate for modelling vehicle-pedestrian interactions compared to gap time. Thirdly, pedestrian crash risk significantly increases when they interact with two-wheelers in contrast with interactions involving buses where the crash risk decreases. Fourthly, pedestrian crash risk decreases when they cross in groups compared to crossing individually. Finally, pedestrian crash risk is positively related to average vehicle speed, pedestrian speed, and five-minute post encroachment time counts less than 1.5 s. Further, different block sizes are tested for the block maxima model, and the five-minute block size yields the most accurate and precise pedestrian crash estimates. These findings demonstrate the applicability of extreme value analysis for heterogeneous and disordered traffic conditions, thereby facilitating proactive safety management in disordered and undisciplined lane conditions.

Evaluating the reliability of automatically generated pedestrian and bicycle crash surrogates.

Vulnerable Road Users (VRUs), such as pedestrians and bicyclists, are at a higher risk of being involved in crashes with motor vehicles, and crashes involving VRUs also are more likely to result in severe injuries or fatalities. Signalized intersections are a major safety concern for VRUs due to their complex dynamics, emphasizing the need to understand how these road users interact with motor vehicles and deploy evidence-based safety countermeasures. Given the infrequency of VRU-related crashes, identifying conflicts between VRUs and motorized vehicles as surrogate safety indicators offers an alternative approach. Automatically detecting these conflicts using a video-based system is a crucial step in developing smart infrastructure to enhance VRU safety. However, further research is required to enhance its reliability and accuracy. Building upon a study conducted by the Pennsylvania Department of Transportation (PennDOT), which utilized a video-based event monitoring system to assess VRU and motor vehicle interactions at fifteen signalized intersections in Pennsylvania, this research aims to evaluate the reliability of automatically generated surrogates in predicting confirmed conflicts without human supervision, employing advanced data-driven models such as logistic regression and tree-based algorithms. The surrogate data used for this analysis includes automatically collectable variables such as vehicular and VRU speeds, movements, post-encroachment time, in addition to manually collected variables like signal states, lighting, and weather conditions. To address data scarcity challenges, synthetic data augmentation techniques are used to balance the dataset and enhance model robustness. The findings highlight the varying importance and impact of specific surrogates in predicting true conflicts, with some surrogates proving more informative than others. Additionally, the research examines the distinctions between significant variables in identifying bicycle and pedestrian conflicts. These findings can assist transportation agencies to collect the right types of data to help prioritize infrastructure investments, such as bike lanes and crosswalks, and evaluate their effectiveness.

Safety effects of bypass lanes at unsignalized three-leg junctions.

Bypass lanes are a low-cost measure to increase capacity at unsignalized T-junctions without left-turn lanes that allow through-traffic to pass left-turning vehicles on the right. There is very limited knowledge about the safety effects of bypass lanes. We found six previous studies that could be summarized by means of meta-analysis, and the results show an average accident reduction of 10 percent. However, the results from previous studies are inconsistent and may be biased. Therefore, the present study has estimated safety effects of by-pass lanes in Norway, based on a sample of 2,227 T-junctions (incl. 94 with bypass-lanes) for which relevant data was available for a period of up to 10 years. We developed accident prediction models and conducted before-after analyses. The accident prediction models show that junctions with bypass lanes have 82 percent more accidents than junctions without bypass lanes, when controlling for endogeneity. Endogeneity occurs when the implementation of a measure is conditional on the frequency of crashes, as has been the case with bypass lanes. The before-after analysis shows that average accident numbers decrease after the installation of bypass lanes. However, when controlling for regression-to-the-mean (RTM), average accident numbers increase. RTM means that accident numbers would have been likely to decrease even without any measure because they had been exceptionally high in the before period. The control for potential biases in our study is likely to contribute to the discrepancy between results from our study and previous studies, most of which have not controlled for the same potential biases. We conclude therefore that bypass lanes, although favorable for capacity, are likely to be unfavorable for safety when compared to other unsignalized T-junctions without left-turn lanes. Unfavorable safety effects may partly be due to site specific conditions, such as road alignment and sight conditions, that contribute to rear-end collision risk or inappropriate driver behavior. However, this does not necessarily mean that bypass lanes never should be used. For example, at junctions where a bypass lane may solve capacity problems, and where site-specific conditions are favorable, bypass lanes may still be an acceptable solution.

Understanding How Green Space Naturalness Impacts Public Well-Being: Prospects for Designing Healthier Cities.

Statement of problem: Urbanization has brought significant advancements in human well-being; however, it poses challenges to urban green spaces (UGSs), affecting environmental quality and public health. Research gap: Previous studies have established the importance of UGSs for urban well-being but have not sufficiently explored how the naturalness of these spaces-ranging from untouched natural areas to human-designed landscapes-affects mental health outcomes in the context of developing countries, particularly Brazil. Purpose: This study aimed to bridge the research gap by investigating the relationship between the degree of naturalness in UGSs and mental health among residents of Brazilian metropolitan areas. Method: Data were collected through an online survey involving 2136 respondents from various Brazilian urban regions. The study used Welch's ANOVA and Games-Howell post hoc tests to analyze the impact of UGS naturalness on mental health, considering depression, anxiety, and stress levels. Results and conclusions: The findings revealed that higher degrees of naturalness in UGSs significantly correlate with lower levels of mental distress. These results underscore the necessity of integrating natural elements into urban planning to enhance public health. Practical implications: Urban planners and policymakers are encouraged to prioritize the preservation and creation of naturalistic UGSs in urban environments to improve mental health outcomes. Future directions: Further research should explore the specific attributes of naturalness that most contribute to well-being and examine the scalability of these findings across different cultural and environmental contexts.

Exploring the Relationship between Built Environment Attributes and Physical Activity in Lower-Income Aging Adults: Preliminary Insights from a Multi-Level Trial.

The built environment has been linked to physical activity (PA) behaviors, yet there is limited knowledge of this association among lower-income midlife and older adults who are insufficiently active. The present cross-sectional study utilized baseline data collected between October 2017 and November 2019 from a clustered randomized controlled trial to determine how built environment attributes were associated with PA behaviors among midlife and older adults (n = 255) residing in or near affordable housing sites (n = 10). At each site, perceptions of the built environment were collected and scored at the participant level via the abbreviated Neighborhood Environment Walkability Survey (NEWS-A), while objective built environment attributes were measured and scored by trained research staff using the Physical Activity Resource Assessment (PARA). Multiple PA behaviors-walking, total PA, and moderate-to-vigorous PA (MVPA) (min/wk)-were measured using the validated Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire. Adjusted linear regression models examined associations between NEWS-A measures and PA behaviors, and site-level correlations between PARA measures and PA behaviors were examined using Spearman's rank correlations. At the participant level, adjusted models revealed that a one point increase in the NEWS-A aesthetics score was associated with a 57.37 min/wk increase in walking (ß = 57.37 [95% CI: 20.84, 93.91], p = 0.002), with a similar association observed for street connectivity and MVPA (ß = 24.31 min/wk [95% CI: 3.22, 45.41], p = 0.02). At the site level, MVPA was positively correlated with the quality of the features of local, PA-supportive environmental resources (ρ = 0.82, p = 0.004). Findings indicate that participant- and site-level measures of the built environment may play a role in promoting PA behavior among this demographic and similar populations. Results also suggest that improvements in aesthetic attributes and street connectivity, along with enhancing the quality of local, PA-supportive environmental resources, may be effective strategies for promoting physical activity among lower-income midlife and older adults.

A systematic review on the associations between the built environment and adult's physical activity in global tropical and subtropical climate regions.

BACKGROUND: Physical inactivity is a major public health concern, exacerbated in countries with a (sub)tropical climate. The built environment can facilitate physical activity; however, current evidence is mainly from North American and European countries with activity-friendly climate conditions. This study explored associations between built environment features and physical activity in global tropical or subtropical dry or desert climate regions. METHODS: A systematic review of four major databases (Web of Science, Scopus, PubMed, and SportDISCUS) was performed. To be included, studies had to investigate associations between perceived or objective built environment characteristics and adult's physical activity and had to be conducted in a location with (sub)tropical climate. Each investigated association was reported as one case and results were synthesized based upon perceived and objectively assessed environment characteristics as well as Western and non-Western countries. Study quality was evaluated using a tool designed for assessing studies on built environment and physical activity. RESULTS: Eighty-four articles from 50 studies in 13 countries with a total of 2546 built environment-physical activity associations were included. Design (connectivity, walking/cycling infrastructure), desirability (aesthetics, safety), and destination accessibility were the built environment characteristics most frequently associated with physical activity across the domains active transport, recreational physical activity, total walking and cycling, and moderate-to-vigorous physical activity, particularly if multiple attributes were present at the same time. Very few studies assessed built environment attributes specifically relevant to physical activity in (sub)tropical climates. Most studies were conducted in Western countries, with results being largely comparable with non-Western countries. Findings were largely generalizable across gender and age groups. Results from natural experiments indicated that relocating to an activity-friendly neighborhood impacted sub-groups differently. CONCLUSIONS: Built environment attributes, including destination accessibility, connectivity, walking and cycling infrastructure, safety, and aesthetics, are positively associated with physical activity in locations with (sub)tropical climate. However, few studies focus on built environment attributes specifically relevant in a hot climate, such as shade or indoor recreation options. Further, there is limited evidence from non-Western countries, where most of the urban population lives in (sub)tropical climates. Policy makers should focus on implementing activity-friendly environment attributes to create sustainable and climate-resilient cities.

A variable speed limit control approach for freeway tunnels based on the model-based reinforcement learning framework with safety perception.

To improve the traffic safety and efficiency of freeway tunnels, this study proposes a novel variable speed limit (VSL) control strategy based on the model-based reinforcement learning framework (MBRL) with safety perception. The MBRL framework is designed by developing a multi-lane cell transmission model for freeway tunnels as an environment model, which is built so that agents can interact with the environment model while interacting with the real environment to improve the sampling efficiency of reinforcement learning. Based on a real-time crash risk prediction model for freeway tunnels that uses random deep and cross networks, the safety perception function inside the MBRL framework is developed. The reinforcement learning components fully account for most current tunnels' application conditions, and the VSL control agent is trained using a deep dyna-Q method. The control process uses a safety trigger mechanism to reduce the likelihood of crashes caused by frequent changes in speed. The efficacy of the proposed VSL strategies is validated through simulation experiments. The results show that the proposed VSL strategies significantly increase traffic safety performance by between 16.00% and 20.00% and traffic efficiency by between 3.00% and 6.50% compared to a fixed speed limit approach. Notably, the proposed strategies outperform traditional VSL strategy based on the traffic flow prediction model in terms of traffic safety and efficiency improvement, and they also outperform the VSL strategy based on model-free reinforcement learning framework when sampling efficiency is considered together. In addition, the proposed strategies with safety triggers are safer than those without safety triggers. These findings demonstrate the potential for MBRL-based VSL strategies to improve traffic safety and efficiency within freeway tunnels.

Identifying multilevel predictors of behavioral outcomes like park use: A comparison of conditional and marginal modeling approaches.

This study compared marginal and conditional modeling approaches for identifying individual, park and neighborhood park use predictors. Data were derived from the ParkIndex study, which occurred in 128 block groups in Brooklyn (New York), Seattle (Washington), Raleigh (North Carolina), and Greenville (South Carolina). Survey respondents (n = 320) indicated parks within one half-mile of their block group used within the past month. Parks (n = 263) were audited using the Community Park Audit Tool. Measures were collected at the individual (park visitation, physical activity, sociodemographic characteristics), park (distance, quality, size), and block group (park count, population density, age structure, racial composition, walkability) levels. Generalized linear mixed models and generalized estimating equations were used. Ten-fold cross validation compared predictive performance of models. Conditional and marginal models identified common park use predictors: participant race, participant education, distance to parks, park quality, and population >65yrs. Additionally, the conditional mode identified park size as a park use predictor. The conditional model exhibited superior predictive value compared to the marginal model, and they exhibited similar generalizability. Future research should consider conditional and marginal approaches for analyzing health behavior data and employ cross-validation techniques to identify instances where marginal models display superior or comparable performance.