Sustainable design of pavement systems in highly urbanized context: A lifecycle assessment

Substantial amount of resources is consumed by pavement systems, which have resulted considerable environmental impacts. Understanding the environmental impacts would provide opportunity for reducing resource consumption and informing decision-makers in the process of designing sustainable pavement. There is a lacking of comprehensive and comparative sustainability assessment of pavement systems in highly urbanized context currently. Therefore, this study aims to design and comprehensively evaluate the environmental performance of the commonly adopted pavement systems in highly urbanized context using lifecycle assessment (LCA) technique through a case in Hong Kong. According to the codes and practices of Hong Kong, two pavement systems including flexible and rigid pavements were designed based on the same road section. After that interviews with structured questionnaire were conducted to collect relevant practical information of pavement construction and maintenance from the relevant professional bodies and experts for the subsequent LCA of such designs. The LCA results reveal that the two mid-point impacts of global warming potential and mineral extraction are 21% and 54% higher for rigid pavement than for flexible pavement. Yet, the end-point results indicate that flexible pavement is associated with 64%, 65%, and 69% higher human health impact, ecosystem quality damage, and resource damage, respectively. Material production and transportation contribute significantly to the total impact in the two pavement systems. For instance, it is about 57% and 97% of the total global warming potential for flexible and rigid pavements, respectively. The overall results demonstrated that 49% higher total impact was found for flexible pavement than rigid pavement. Therefore, the use of more recycled and environmentally friendly materials can potentially enhance the environmental sustainability of both pavement systems. The findings should provide useful information to the design and selection of sustainable pavement structures in resource-scarce highly-urbanized cities.

Contextual influences on chronic illness: A multi-level analysis in the twin cities of Ramallah and Al Bireh in the occupied Palestinian Territory

The features of the urban environment can support human health as well as harm it, but less is known about such influences in the context of middle eastern countries. The association between green space and the political classifications of the urban environment and the risk of chronic illness was investigated in a novel setting, the twin cities of Ramallah and Albireh in the occupied Palestinian territory. We used a generalised multi-level regression analysis to link the 2017 census data with Geographic Information System data. We modelled individuals at level one (n = 54693) and areas of residence at level two (n = 228), adjusting for individual demographic and socio-economic characteristics.

The proportions of ‘mixed’ trees in residential areas had a significant inverse association with the risk of chronic illness. On the political dimension, only living in a refugee camp had a significant positive association with chronic illness; however, this was largely explained and rendered non-significant when green space variables were entered into the models. Our ability to differentiate between several types of green space was important, as findings demonstrated that not all types were associated with reduced risk of chronic illness. Our results from a middle eastern setting add to the largely Western existing evidence, that trees in urban settings are important and beneficial to human health. Researchers and policymakers should pay more attention to the health consequences of refugee camps but also the role of trees in benefiting individuals' health in such a disadvantaged context.

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The study explored the urban political and environmental impacts on health in the Palestinian context.

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Living in a refugee camp is positively associated with the risk of chronic illness, over and above individual characteristics.

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Residential areas mixed trees are inversely associated with chronic illness, and explained the association with refugee camps.

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Not all types of green space are associated with a reduced risk of chronic illness.

Study of COVID-19 pandemic in London (UK) from urban context

COVID-19 transmission in London city was discussed in this work from an urban context. The association between COVID-19 cases and climate indicators in London, UK were analysed statistically employing published data from national health services, UK and Time and Date AS based weather data. The climatic indicators included in the study were the daily averages of maximum and minimum temperatures, humidity, and wind speed. Pearson, Kendall, and Spearman rank correlation tests were selected for data analysis. The data was considered up to two different dates to study the climatic effect (10th May in the first study and then updated up to 16th of July in the next study when the rest of the data was available). The results were contradictory in the two studies and it can be concluded that climatic parameters cannot solely determine the changes in the number of cases in the pandemic. Distance from London to four other cities (Birmingham, Leeds, Manchester, and Sheffield) showed that as the distance from the epicentre of the UK (London) increases, the number of COVID-19 cases decrease. What should be the necessary measure to be taken to control the transmission in cities have been discussed.

Exposures at day labor corners: using existing georeferenced data to describe features of urban environments

PURPOSE

Latino day laborers are male immigrants from mainly Mexico and Central America who congregate at corners, that is, informal hiring sites, to solicit short-term employment. Studies describing the occupational environment of Latino day laborers traditionally measure jobsite exposures, not corner exposures. We sought to elucidate exposures at corners by describing their demographic, socioeconomic, occupational, business, built, and physical environmental characteristics and by comparing corner characteristics with other locations in a large urban county in Texas.

METHODS

We used multiple publicly available data sets from the U.S. Census, local tax authority, Google's Nearby Places Application Programming Interface, and Environmental Protection Agency at fine spatial scale to measure 34 characteristics of corners with matched comparison locations.

RESULTS

Corners were located close to highways, high-traffic intersections, hardware and moving stores, and gas stations. Corners were in neighborhoods with large foreign-born and Latino populations, high rates of limited English proficiency, and high construction-sector employment.

CONCLUSIONS

Publicly available data sources describe demographic, socioeconomic, occupational, business, built, and physical environment characteristics of urban environments at fine spatial scale. Using these data, we identified unique corner-based exposures experienced by day laborers. Future research is needed to understand how corner environments may influence health for this uniquely vulnerable population.

Food insufficiency is associated with depression among street-involved youth in a Canadian setting

OBJECTIVE

Food insufficiency, defined by the experience of hunger, is known to be prevalent and a source of health-related harm among-street involved youth, but little is known about its relationship with depression in this population. Therefore, we sought to assess the association between food insufficiency and symptoms of depression among a cohort of street-involved youth.

DESIGN

Multivariable logistic regression was used to assess the relationship between food insufficiency, defined as being hungry but not having enough money to buy food, and depression as measured by the Center for Epidemiological Studies Depression (CES-D) scale.

SETTING

Data from April 2006 to November 2013 were derived from the At-Risk Youth Study (ARYS), a prospective cohort of street-involved youth who use illicit drugs in Vancouver, Canada.

SUBJECTS

There were 1066 street-involved youth enrolled in the study, including 340 (31·9 %) females.

RESULTS

Of 1066 youth enrolled in the study, 724 (67·9 %) reported some food insufficiency and 565 (53·0 %) met criteria for depression. Compared with youth who did not report food insufficiency, those who reported often experiencing food insufficiency had a higher likelihood of reporting depression (adjusted OR=2·52; 95 % CI 1·74, 3·67), as did those who reported sometimes experiencing food insufficiency (adjusted OR=1·99; 95 % CI 1·47, 2·70).

CONCLUSIONS

Food insufficiency was prevalent and associated in a dose-dependent trend with symptoms of depression among street-involved youth in our setting. Findings highlight the need to address the nutritional and mental health needs of youth and identify pathways by which food insufficiency may contribute to depression among vulnerable populations.

Knowledge and possession of take-home naloxone kits among street-involved youth in a Canadian setting: a cohort study

BACKGROUND

The distribution of take-home naloxone (THN) kits has been an important strategy in reducing overdose fatalities among people who use drugs. However, little is known about the use of THN among youth who are street-involved. The present study explores knowledge and possession of THN among street-involved youth in a Canadian setting.

METHODS

Data were derived from the At-Risk Youth Study (ARYS), a prospective cohort of street-involved youth age 14-28 at enrollment in Vancouver, Canada. Participants completed a standardized questionnaire, which included items related to knowledge and possession of THN, sociodemographic characteristics, and substance use-related factors. Multivariable logistic regression models were used to identify factors independently associated with knowledge and possession of THN.

RESULTS

Between December 2014 and November 2016, 177 youth were interviewed, including 68 females (38.4%). While 126 (71.2%) participants reported knowledge of THN, only 40 (22.6%) possessed a THN kit. Caucasian/white ethnicity was found to be positively associated with both knowledge and possession of THN (both p < 0.05). Public injection drug use in the last 6 months was found to be positively associated with knowledge of THN, while daily heroin use and daily methamphetamine use were associated with possession of THN (all p < 0.05). Male gender was negatively associated with possession of THN (p < 0.05).

CONCLUSIONS

These findings highlight important gaps between knowledge and possession of THN among youth and the need to increase participation in THN programs among specific populations including non-white and male youth. Further research is needed to gain a better understanding of the barriers that may prevent certain youth from acquiring THN kits.

Exploring the safety in numbers effect for vulnerable road users on a macroscopic scale

A "Safety in Numbers" effect for a certain group of road users is present if the number of crashes increases at a lower rate than the number of road users. The existence of this effect has been invoked to justify investments in multimodal transportation improvements in order to create more sustainable urban transportation systems by encouraging walking, biking, and transit ridership. The goal of this paper is to explore safety in numbers effect for cyclists and pedestrians in areas with different levels of access to multimodal infrastructure. Data from Chicago served to estimate the expected number of crashes on the census tract level by applying Generalized Additive Models (GAM) to capture spatial dependence in crash data. Measures of trip generation, multimodal infrastructure, network connectivity and completeness, and accessibility were used to model travel exposure in terms of activity, number of trips, trip length, travel opportunities, and conflicts. The results show that a safety in numbers effect exists on a macroscopic level for motor vehicles, pedestrians, and bicyclists.

Twenty years of socioeconomic inequalities in premature mortality in Barcelona: The influence of population and neighbourhood changes

The objective of this study was to analyse trends in socioeconomic inequalities in premature mortality in Barcelona from 1992 to 2011, accounting for population changes. We conducted a repeated cross-sectional study of the Barcelona population (25-64 years) using generalized linear mixed models for trend analysis, and found that socioeconomic inequalities in premature mortality persisted between neighbourhoods, but tended to diminish. However, the reduction in inequality was related to an increase in the number of foreign-born individuals mainly in socioeconomic disadvantaged neighbourhoods, in which the decrease in premature mortality was more marked. To study trends in geographical inequalities in mortality, it is essential to understand demographic changes occurred in different places related to local levels of deprivation.